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Please write an abstract with title: Demand Analysis of Taxi Passenger-carrying Hot Spot Areas Based on XGBoost Algorithm, and key words: Clustering algorithms, Euclidean distance, Companies, Big Data, Prediction algorithms, Eigenvalues and eigenfunctions, Artificial intelligence. Abstract: In order to study the demand prediction of taxi passenger-carrying hot spot areas, firstly, the density-based DBSCAN clustering algorithm is used to identify the hot spot areas and delineate the boundaries of the hot spot areas. And combined with the demand characteristics of taxi, the demand prediction of hot spot areas is carried out by using XGBoost algorithm without Fourier eigenvalues and XGBoost algorithm with Fourier eigenvalues. By comparing the mean absolute percentage error (MAPE), the prediction accuracy of the latter is significantly improved.
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Please write an abstract with title: A Linear Reliability-Evaluated Unit Commitment, and key words: Reliability, Maintenance engineering, Power system reliability, Production, Costs, Adaptation models, Reactive power. Abstract: Reliability evaluation has developed a trend of embedding unit commitment to replace power flow for more accurate operation strategies, while its potential reverse, embedding reliability evaluation in unit commitment, has yet to see equal exploration. This unrecognized, yet meaningful, technical attempt will encounter modeling and computational burden, largely caused by the recursive function and non-convex structure of numerical reliability evaluation equipped with the necessary repair mechanism. To tackle this challenge, this study proposes a linear routine that overcomes the non-convexity of reliability evaluation and accommodates it in unit commitment, which is expected to bring optimal operation and reliability evaluation to a new era by enabling them both conducted at the same pace.
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Please write an abstract with title: A systematic construction of self-dual codes, and key words: Block codes, Turbo codes, Vectors, Hamming weight, Lead, Tensile stress, Fast Fourier transforms, Bit error rate, Encoding, Symmetric matrices. Abstract: A new coding construction scheme of block codes using short base codes and permutations that enables the construction of binary self-dual codes is presented in Cadic et al. (2001) and Carlach et al. (1999, 2000). The scheme leads to doubly-even (resp,. singly-even) self-dual codes provided the base code is a doubly-even self-dual code and the number of permutations is even (resp., odd). We study the particular case where the base code is the [8, 4, 4] extended Hamming. In this special case, we construct a new [88, 44, 16] extremal doubly-even self-dual code and we give a new unified construction of the five [32, 16, 8] extremal doubly-even self-dual codes.
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4,303
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Please write an abstract with title: A digitally skew correctable multi-phase clock generator using a master-slave DLL, and key words: Clocks, Master-slave, Delay, Pulse circuits, Pulsed power supplies, Pulse generation, Circuit stability, Power supplies, Fluctuations, Circuit simulation. Abstract: This paper presents a digitally skew correctable multi-phase clock generator using a master-slave delay-locked-loop(DLL). The multi-phase clock generator is for a distributed S/H stage in interleaved ADC's. The delay of the slave DLLs, whose outputs are used for S/H circuits, is controlled by a very short pulse generated by a master DLL. This technique allows us to control the skew of the multi-phase clocks with the resolution of less than 1 ps. The master-slave DLL also has a good stability to the power supply fluctuations. Simulation results show that the clock skew can be corrected with the resolution of 0.2ps using a current output DAC with a resolution of 0.1 /spl mu/A.
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4,304
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Please write an abstract with title: Research on Fault Inversion Verification Technology Based on Practical-Test-Platform of Distribution Network, and key words: Information science, Software packages, Network topology, Simulation, Distribution networks, Topology, Circuit faults. Abstract: The practical test can truly reflect the electromagnetic transient characteristics generated in the operation process of distribution network, but the test process is complex, the topology change is inconvenient, and the high-voltage test also has a certain degree of danger, which is not suitable for frequent test and display. This paper proposes an inversion verification technology based on the monitoring data of the Practical-Test-Platform of distribution network. Based on the data obtained in the practical test, constructed the $\pi$ type equivalent circuit line. The positive sequence impedance and zero sequence impedance parameters of $\pi$ type equivalent circuit structure of all line sections of the Practical-Test-Platform are derived by using the calculation principle of symmetrical sequence component. Then the Practical-Test-Platform is digitized in MATALAB/ Simulink environment, and the inversion is carried out in the way of execution of a ground-short-circuit fault test respectively on the same node. The simulation results show that the ground-short-circuit fault waveform obtained by this inversion method has a high similarity with the original fault, which verifies the high referenced value of the inversion verification technology.
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Please write an abstract with title: SSI, academia and industry colaboration [colaboration read collaboration], and key words: Collaboration, Computer applications, Application software. Abstract: While software construction was a science, the design and construction of software was viewed as the central activity. Standards, middleware, and mature software development methodologies has moved this to one of several co-equal application development activities. To effectively bring this approach to the IT classroom, a partnership and academia is required. The Shared Software Initiative community fills this role.
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4,306
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Please write an abstract with title: Inverter Nonlinearity Compensation for Open-Winding Machine With Dual Switching Modes, and key words: Inverters, Switches, Pulse width modulation, Topology, Voltage, Harmonic analysis, Aerospace electronics. Abstract: In this article, a novel inverter nonlinearity compensation method is proposed for open-winding (OW) machines fed by isolated dc-bus dual two-level three-phase inverters with dual switching modes. Inverter nonlinearity of dual inverters is analyzed in both balanced and unbalanced switching modes, and the different voltage distortions are utilized for a closed-loop inverter nonlinearity compensation by alternately applying the two switching modes. The proposed strategy needs no off-line measurement for the parameters of dual inverters and the electrical machine, and can also deal with the variation of inverter parameters in different operation conditions. Furthermore, the proposed strategy can overcome issues in conventional current harmonic-based methods, such as the need for accurate rotor position and preset compensation voltage curves. Experimental results verify the performance of the proposed inverter nonlinearity compensation method.
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4,307
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Please write an abstract with title: A System Analysis of Noise Influences on the Imaging Performance of Millimeter Wave MIMO Radars, and key words: Phase noise, Microwave measurement, Radar measurements, Radar, Radar imaging, Millimeter wave radar, Microwave circuits. Abstract: In this paper a thorough system analysis to evaluate the overall imaging performance of millimeter wave radar systems is presented. All relevant noise influences and their influence on the system performance are considered. A comparison of two imaging radar systems at 160 GHz with different hardware architectures is discussed, one of which is based on monolithic microwave integrated circuits (MMICs) optimized for low phase noise. Radar measurements are performed to evaluate the achievable imaging performance with both realized radar demonstrators. It is shown that the optimization of the phase noise of a single MMIC is not necessarily advantageous when used for multi-channel radar systems.
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4,308
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Please write an abstract with title: Array Antenna System for Wireless Power Transfer (WPT) System at 6.78 MHz, and key words: Antenna arrays, Transmitting antennas, Receiving antennas, Antenna measurements, Voltage measurement, Power measurement. Abstract: This paper proposes an array antenna system for wireless power transfer (WPT) at 6.78GHz. The development of new techniques to increase power transmission and covered area is proposed. The power transmitter with a power output of 22-60 W is designed. Using the principle of magnetic resonance technique, the transmitting array antenna consists of 4 antennas and arranged in the same plane. The in-phase signal feeding technique is selected. Therefore, the electric field spreads around the array transmitting antenna. Measurement results found that the maximum received power of 9.4W. The average value is 3.5W which is sufficiently used to charge the batteries. Charging time depends on the position and received power.
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4,309
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Please write an abstract with title: Spectral range of the ac Josephson effect in [001]-tilt YBa/sub 2/Cu/sub 3/O/sub 7-x/ bicrystal junctions, and key words: Josephson effect, Frequency, Voltage, Physics, Radiation monitoring, Resonance, High temperature superconductors, Josephson junctions, Detectors, Solid state circuits. Abstract: We have studied the ac Josephson effect in YBa/sub 2/Cu/sub 3/O/sub 7-x/ bicrystal junction by monitoring the voltage dependence of the dc current response /spl Delta/I(V) induced by low-power monochromatic radiation with the frequencies f/sub i/. The intensity of odd-symmetric resonances in the function /spl Delta/I(V) near the voltages V/sub i/=hf/sub i//2e is proportional to the amplitude of Josephson oscillations at the frequency f/sub i/. The resonance intensities have been mapped as a function of the Josephson frequency f/sub i/ in the range from 5 GHz to 5 THz, the junction resistance R/sub n/ in the range from 0.4 to 80 Ohm and junction characteristic voltages I/sub c/R/sub n/ in the range from 5 /spl mu/V to 1.8 mV. The central frequency of the range was scaled with the I/sub c/R/sub n/-product of the junction and it could be shifted from GHz-range to the THz-range by a temperature decrease. The spectral range was limited by an enhanced noise broadening of the Josephson linewidth at low frequencies and by increased dc Joule heating at high frequencies.
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4,310
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Please write an abstract with title: Identification of Brain Tumors using Volume rendering Techniques, and key words: Image segmentation, Solid modeling, Three-dimensional displays, Magnetic resonance imaging, Two dimensional displays, Rendering (computer graphics), Tumors. Abstract: The aim of this work is to compute the accurate volumes (3D) of tumors from 2D MR images. In MR images, the presence of tumor differs significantly because of the variation of the tissue cells. A perfect segmentation technique must be selected to separate the tumor tissue from the nearby healthy brain tissue to extract precise volume models. This research explains an effective technique for volume rendering of brain from 2D MRI slices. For medical research, the assessment of the pre-operative volume of tumor is highly essential. The 3D segmented tumor comprises of grey pixel values of the original MR image with well-defined tumor edges.
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4,311
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Please write an abstract with title: 17.9 A High-Conversion-Ratio and 97.4% Peak-Efficiency 3-Switch Boost Converter with Duty-Dependent Charge Topology for 1.2A High Driving Current and 20% Reduction of Inductor DC Current in MiniLED Applications, and key words: Capacitors, Loading, Light emitting diodes, Hardware, Topology, Solid state circuits, Inductors. Abstract: Today’s miniLED displays can be divided into multiple arrays. Each miniLED array with 900 pixels can have 60 channels where each channel has 15 LEDs connected in series. To drive multi-channel miniLEDs in parallel from a low input voltage $\mathrm{V}_{\mathrm{I}\mathrm{N}}$(=6V), a boost converter with high output voltage (up to 30V) and high output current (up to 1. 2A for 2000 nits) is required where the conversion ratio (CR $=\mathrm{V}_{\mathrm{OUT}}/\mathrm{V}_{\mathrm{I}\mathrm{N}}$) is 5. Since the inductor current $I_{L}=I_{LOAD}/(1-D)$ of the conventional 2-switch (2S) boost converter is high, where $\mathrm{I}_{\mathrm{LO}\mathrm{A}\mathrm{D}}$ is the load current and D is the duty cycle, 2S boost converters have low efficiency and high output voltage ripple. Although the boost converter assisted by a series flying capacitor $\mathrm{C}_{\mathrm{F}}$ can reduce the inductor current level to improve efficiency [1] –[5], $\mathrm{C}_{\mathrm{F}}$ lacks energy under high CR and high loading conditions. At the top of Fig. 17.9.1, both techniques in [1] and [2] charge the $\mathrm{C}_{\mathrm{F}}$ during $\varphi$ 2. ln case of high CR, the duration of $\varphi$ 2 becomes small to seriously affect the charging time. Hence, due to insufficient charge stored in $\mathrm{C}_{\mathrm{F}}$, the driving capability will decrease. At no load (left of Fig. 17.9.2), [1] fails to regulate and D is 0.87 in [2] to haveCR=5. lnterestingly, both$$ [1] and [2] fail to have CR=5 at load current =1.2A. Although additional dual channel-interleaved three-level buck-boost (DTLBB) structure in [1] can alternatively charge two flying capacitors, the hardware overhead is double and the quiescent current becomes high.
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Please write an abstract with title: Analysis of power ramping schemes for UTRA-FDD random access channel, and key words: Delay, AWGN, Power engineering and energy, Frequency conversion, Radio control, Control systems, Base stations, Performance analysis, Throughput, Design engineering. Abstract: The random access channel (RACH) in a universal terrestrial radio access frequency division duplex (UTRA-FDD) system is a contention-based channel mainly used to carry control information from mobile stations to base stations. The transmission of a random access request contains two steps, preamble transmission and message transmission. In preamble transmission, a power ramping technique is used to favor the delayed preambles by stepping up the transmission power after each unsuccessful access. In doing so, the success of transmitting a long-delayed preamble is increased due to the power capture effect. We analyze the blocking and throughput performance of preamble transmission under three power ramping schemes with fixed, linear and geometric step sizes. Also, we compare the interference caused by different power ramping schemes.
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4,313
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Please write an abstract with title: Singularities in minimax optimization of networks, and key words: Minimax techniques, Convergence, Testing, Algorithm design and analysis, Transformers, Circuit optimization, Councils, Numerical analysis, Electromagnetics, Frequency. Abstract: A theoretical treatment of singularities in nonlinear minimax optimization problems, which allows for a classification in regular and singular problems, is presented. A theorem for determining a singularity that is present in a given problem is formulated. A group of problems often used in the literature to test nonlinear minimax algorithms, i.e., minimax design of multisection quarter-wave transformers, is shown to exhibit singularities and the reason for this is pointed out. Based on the theoretical results presented an algorithm for nonlinear minimax optimization is developed. The new algorithm maintains the quadratic convergence property of a recent algorithm by Madsen et al. when applied to regular problems and it is demonstrated to significantly improve the final convergence on singular problems.
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4,314
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Please write an abstract with title: Improved Market Mechanism for Energy Storage Based on Flexible State of Energy, and key words: Energy storage, Generators, Electric vehicles, Electricity supply industry, Wind power generation, Power transmission lines, Power grids. Abstract: In this paper, a new operational mode is proposed for energy storage, in which an improved semi-centralized mechanism is proposed for energy storage to participate in the day-ahead energy market. The new operational mode, i.e., the flexible state-of-energy (SOE) mode, is proposed based on the previous fixed SOE mode, under which the final SOE of energy storage at the end of the last period of the scheduling horizon is not limited to a predefined value. Accordingly, the value of the SOE is introduced to quantify the deviation cost of the final SOE from the predefined value. Under the proposed market mechanism, energy storage submits to the system operator the unit charging and discharging costs and the value of the SOE. The system operator dispatches the charging and discharging power of energy storage according to the data submitted and system operations. A comparative analysis is conducted in the case studies, and results demonstrate that the proposed mechanism is efficient in further realizing the flexibility potential of energy storage and reducing the total cost of the power system.
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4,315
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Please write an abstract with title: An efficient heuristic for designing logical overlay networks for the reliable label switched paths in IP networks, and key words: Intelligent networks, IP networks, Telecommunication traffic, Traffic control, Computer network reliability, Multiprotocol label switching, Heuristic algorithms, Routing protocols, Cathode ray tubes, Computer networks. Abstract: We tackle the design problem of the logical overlay network used by the reliable label switched paths (ILSPs) in Internet protocol (IP) networks. The design problem consists to find the minimum capacity on each link and the routing metrics that ensure the successful rerouting of the reliable LSPs for all failure scenarios of interest to the network planner. The objective is to minimize the cost of the network overlay. A mixed nonlinear bi-level mathematical programming model is proposed for the problem and a tabu-search heuristic algorithm is designed to find "good" solutions of the model. Numerical results show that quasi-optimal solutions can be found with the proposed algorithm.
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4,316
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Please write an abstract with title: Optimizing Computational Resources for Edge Intelligence Through Model Cascade Strategies, and key words: Computational modeling, Internet of Things, Task analysis, Cloud computing, Predictive models, Optimization, Sustainable development. Abstract: As the number of interconnected devices increases and more artificial intelligence (AI) applications upon the Internet of Things (IoT) start to flourish, so does the environmental cost of the computational resources needed to send and process all the generated data. Therefore, promoting the optimization of AI applications is a key factor for the sustainable development of IoT solutions. Paradigms such as Edge Computing are progressively proposed as a solution in the IoT field, becoming an alternative to delegate all the computation to the Cloud. However, bringing the computation to the local stage is limited by the resources’ availability of the devices hosted at the Edge of the network. For this reason, this work presents an approach that simplifies the complexity of supervised learning algorithms at the Edge. Specifically, it separates complex models into multiple simpler classifiers forming a cascade of discriminative models. The suitability of this proposal in a human activity recognition (HAR) context is assessed by comparing the performance of three different variations of this strategy. Furthermore, its computational cost is analyzed in several resource-constrained Edge devices in terms of processing time. The experimental results show the viability of this approach to outperform other ensemble methods, i.e., the Stacking technique. Moreover, it substantially reduces the computational cost of the classification tasks by more than 60% without a significant accuracy loss (around 3.5%). This highlights the potential of this strategy to reduce resource and energy requirements in IoT architectures and promote more efficient and sustainable classification solutions.
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4,317
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Please write an abstract with title: Fault Diagnosis of Modular Multilevel Converter Based on Optimized Support Vector Machine, and key words: Bridge circuits, Support vector machines, Fault diagnosis, Circuit faults, Genetic algorithms, Sociology, Statistics. Abstract: In this paper, the open-circuit fault characteristics of IGBT in Modular multilevel converter(MMC) are studied. A fault diagnosis method based on average value of the three-phase ac current to extract fault characteristics , then an intelligent optimization algorithm for fault detection and location of support vector machine(SVM) is proposed. When a fault occurs, the average value of three-phase ac current is no longer zero, which can detect the occurrence of the faulty SM. When the open-circuit fault occurs in the SMs of different bridge arms, the average value of three-phase ac current produces different dc bias components. According to the change rule of average value in three-phase current, the fault characteristic is extracted, and then the fault is classified and located by the SVM classifier optimized by genetic algorithm. Finally, Simulation and experimental results show that the proposed method can not only detect the fault block module quickly, but also improve the accuracy of fault classification.
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4,318
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Please write an abstract with title: Effects of the field dependent J/sub c/ on the vertical levitation force between a superconductor and a magnet, and key words: Superconducting magnets, Magnetic levitation, Demagnetization, Superconducting materials, Permanent magnets, Magnetic fields, Saturation magnetization, Superconducting magnetic energy storage, Current distribution, Australia. Abstract: The vertical levitation force between a superconductor disk (SC) and a permanent magnet disk (PM) has been calculated from first principles using different J/sub c/(B) relationships of the magnetic field. Based upon the first principles, the current distribution inside the SC induced by the applied inhomogeneous magnetic field generated by the PM and the field profiles have been calculated with a power law E /spl sim/ J relationship: E(J) = E/sub c/(J/J/sub c/(B))/sup n/. The levitation force is highly hysteretic for the approaching and the retreating branches. The saturated current value, magnetization, and levitation force are found to depend strongly on the J/sub c/(B) relations. Features of the supercurrent distribution, the force loop, and the levitation force density are discussed.
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Please write an abstract with title: Joint Optimization of Jamming Type Selection and Power Control for Countering Multifunction Radar Based on Deep Reinforcement Learning, and key words: Deep reinforcement learning, jamming type, multifunction radar (MFR), power control. Abstract: Developing intelligent jamming methods to combat the multifunction radar (MFR) has become a vital task in electronic warfare, because the MFR can tune into different working modes according to surrounding environment information. In this article, we present a solution to the limitations of conventional jamming methods, including strong prior knowledge dependence and inaccurate selection strategies. Specifically, we study a joint optimization of jamming type selection and power control task (JO-JTSPC) for a general radar countermeasure scenario. In particular, we first model the sequential decision-making task JO-JTSPC as a Markov decision process (MDP). Subsequently, considering the differences in the designed action space, we accordingly develop two algorithms, i.e., dueling double deep Q-learning and hybrid proximal policy optimization, to solve the optimization problem. Taking into consideration the threat level of various MFR working modes and the corresponding required jamming effect, we elaborately design the reward function of MDP as a weighted summation of the mode switching factor, jamming performance factor, and jamming power factor. Further, the learned polices of these algorithms are derived based on the designed reinforcement learning elements. Extensive simulation results demonstrate that the proposed algorithms can learn highly adaptive polices in the radar countermeasure scenarios and achieve good jamming performance.
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4,320
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Please write an abstract with title: Spectroscopic Method for Studying the Characteristics of Human Skin, and key words: Spectroscopy, Micrometers, Absorption, Veins, Light emitting diodes, Skin, Reflection. Abstract: The research is devoted to the study of the spectroscopic characteristics of human skin, obtained using the method of near infrared spectroscopy. The experiment uses a LED minispectrometer LMS-R operating in the near infrared range from 1.3 to 2.4 microns. We obtained several data samples, which were compared with each other using one-way analysis of variance. The results obtained show that this method has good prospects in dermatology for the diagnosis and classification of skin diseases.
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4,321
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Please write an abstract with title: Segmented 1.55 /spl mu/m laser with 400% differential quantum efficiency, and key words: Quantum well lasers, Waveguide lasers, Indium phosphide, Diodes, Surface emitting lasers, Particle beam optics, Etching, Electron emission, Radiative recombination, Spontaneous emission. Abstract: By electrically segmenting, and series-connecting an InP ridge laser, we have demonstrated 12-stage lasers with 409 % differential efficiency and 2.6 mA threshold, as well as 3-stage lasers with 51 ohm input impedance and 126 % differential efficiency.
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4,322
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Please write an abstract with title: A Scalable Name Lookup Service for NDN, and key words: Scalability, Information and communication technology, Convergence. Abstract: A lookup service has been identified as an essential part of NDN. NDNS as a name resolution service was proposed since NDN in itself does not have the feature. The NDNS architecture follows the concept of DNS. However, we argue that the architecture will suffer from the scalability issue in the end since it requires orders of magnitude higher performance to deal with content names than with domain names. In this paper, we propose a novel scalable name lookup service for NDN, called NDN Content Identity Service or NCIS, in order to solve it. NCIS allows multiple copies of a content with different names across the network utilizing two different types of distributed hash table. We present the benefits of adopting NCIS into NDN.
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4,323
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Please write an abstract with title: Image Formation of Multifrequency Vibro-Acoustography: Theory and Computational Simulations, and key words: Computational modeling, Stress, Ultrasonic imaging, Acoustic beams, Focusing, Frequency, Acoustic emission, Acoustic transducers, Imaging phantoms, Image resolution. Abstract: This paper presents an extension of vibro-acoustography imaging technique. The standard technique relies on the single-frequency dynamic radiation force (or stress) produced by a highly focused dual-frequency ultrasound beam. We propose a multifrequency vibro-acoustography method based on the radiation stress generated by a beam with multiple frequencies. The system point-spread function (PSF) is obtained in terms of the acoustic emission by a point-target in response to the employed radiation stress. The PSF is evaluated for an eight- and a sixteen-element sector array transducers. Three phantom images are used to show how the system transforms them into observed data. Considering only visual criteria such as contrast and resolution, simulations show the sixteen-element sector transducer renders better images.
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4,324
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Please write an abstract with title: Simurgh: A Fully Decentralized and Secure NVMM User Space File System, and key words: Nonvolatile memory, File systems, Scalability, Linux, High performance computing, Memory management, Metadata. Abstract: The availability of non-volatile main memory (NVMM) has started a new era for storage systems and NVMM specific file systems can support extremely high data and metadata rates, which are required by many HPC and data-intensive applications. Scaling metadata performance within NVMM file systems is nevertheless often restricted by the Linux kernel storage stack, while simply moving metadata management to the user space can compromise security or flexibility. This paper introduces Simurgh, a hardware-assisted user space file system with decentralized metadata management that allows secure metadata updates from within user space. Simurgh guarantees consistency, durability, and ordering of updates without sacrificing scalability. Security is enforced by only allowing NVMM access from protected user space functions, which can be implemented through two proposed instructions. Comparisons with other NVMM file systems show that Simurgh improves metadata performance up to 18x and application performance up to 89% compared to the second-fastest file system.
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4,325
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Please write an abstract with title: A Supersonic Underwater Pulsed Acoustic Source, and key words: Electric breakdown, Magnetic cores, Conferences, Transformers, Cameras, Acoustics, Plasmas. Abstract: A supersonic underwater pulsed acoustic source has been developed at Loughborough University. A 120 kV magnetic core transformer drives electrical breakdown which acts as an acoustic source. The paper will present the design of the system and source, the diagnostic methods used to study breakdown, including an ultra-fast camera, acoustic diagnostics, and analytical techniques employed. The main results will be presented and discussed.
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4,326
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Please write an abstract with title: Study of Rechargeable Batteries Using a Laboratory Teaching Platform, and key words: Batteries, Discharges (electric), Battery charge measurement, Voltage measurement, Electrolytes, Electric variables measurement, Current measurement. Abstract: The aim of this work is a didactic one, namely to achieve simulation of a battery charge and discharge, the purpose being an educational one. The work deals with the design of a laboratory platform, a platform which was made for teaching purposes. By designing and implementing this application students will be able to put into practice the acquired theoretical knowledge. The practical realization is available to the students as a laboratory work for electrical measurements.
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4,327
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Please write an abstract with title: Quasi-Yagi Uda MIMO 2x2 Antenna for 5G Network on Cellular Devices Application, and key words: Antennas, Microstrip antennas, MIMO communication, Baluns, 5G mobile communication, Antenna radiation patterns, Microstrip. Abstract: Telecommunication technology is in preparation for the 5th generation (5G). One of the components that play an essential role is an antenna. The characteristics of an antenna that is small in size, wide bandwidth, and uses the Multiple Input Multiple Output (MIMO) system are needed to be used on a 5G network. In this research, a 2×2 MIMO antenna will be designed for 5G networks on cellular devices that work on Ka-Band frequencies of 25-27 GHz. The quasi-yagi microstrip antenna has been chosen for design because it can meet the 5G network's needs. The Rogers RO4350B substrate with a thickness of 0.762 mm and relative permittivity of 3.66 is used in antenna design. This research consists of three antenna simulation steps using CST Studio Suite, namely antenna design, the antenna balun design, and antenna performance optimization. The results show that the simulation of the MIMO antenna has met the expected specifications. The MIMO antenna has return loss less than -10 dB at Ka-Band with the frequency of 25-27 GHz, the return loss less than -10 dB, mutual coupling less than -20 dB, port impedance approaching 50 Ω, gain in the range of 7.1539.457 dBi, and directional radiation pattern.
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4,328
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Please write an abstract with title: Attacking Adaptive Cuckoo Filters: Too Much Adaptation Can Kill You, and key words: Hash functions, Security, Electronic mail, Adaptive filters, Costs, Information filters, Adaptation models. Abstract: Adaptation has recently been proposed to reduce the false positive rate of approximate membership check filters for applications in which the same elements are checked multiple times. Its operational principle is to adapt the filter when a false positive occurs for a given element, such that subsequent checks of that element do not cause a positive result (as beneficial for example in networking). Security is an important consideration for approximate membership check filters and several attacks have been described in the literature; therefore, it is of interest to study the security of adaptive filters. In this paper, we consider adaptive cuckoo filters and show that an attacker can generate sequences of lookups that cause the filter to continuously adapt and not being able to remove the false positives. This degrades the filter performance due to the adaptation overhead; it also makes it harder for other false positives to be removed, because adaptation can be monopolized by the attacker. This can be done when the attacker has only a black-box access to the filter being able to perform lookups but with no knowledge of the implementation of the filter. The proposed attacks have been implemented and tested to validate their effectiveness in terms of the construction of the attack set and the impact of the attack itself. The evaluation results confirm that adaptation unfortunately increases the attack surface of filters and new mechanisms to protect them should be developed.
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4,329
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Please write an abstract with title: Phase transformation in an n-type FeSi/sub 2/ processed by mechanical alloying, and key words: Isothermal processes, Annealing, Iron, Powders, Silicides, Thermoelectricity, Alloying, Pressing, Metastasis, Semiconductivity. Abstract: N-type Fe/sub 0.98/Co/sub 0.02/Si/sub 2/ powders have been produced by mechanical alloying process and consolidated by vacuum hot pressing. As-milled powders were in a metastable state and fully transformed to /spl beta/-FeSi/sub 2/ phase by subsequent isothermal annealing. However, as-consolidated iron silicides consisted of untransformed mixture of /spl alpha/-Fe/sub 2/Si/sub 5/ and /spl epsiv/-FeSi phases. Isothermal annealing has been carried out to induce the transformation to a thermoelectric semiconducting /spl beta/-FeSi/sub 2/ phase. The transformation behavior of /spl beta/-FeSi/sub 2/ was investigated a modified TGA, SEM and XRD analyses. Isothermal annealing at 830/spl deg/C in vacuum led to the /spl beta/-FeSi/sub 2/ phase transformation, but some residual metallic /spl alpha/- and /spl epsiv/-phases were unavoidable. Microstructures of iron silicides were investigated using SEM. Microharness before and after isothermal annealing was evaluated and correlated with the phase transformation as well as thermoelectric properties.
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4,330
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Please write an abstract with title: Influence of lossy compression techniques on processing precision of astronomical images, and key words: Image coding, Optical variables control, Gamma ray bursts, Karhunen-Loeve transforms, Optical losses, Telescopes, Statistical distributions, Robot vision systems, Cameras, Probability density function. Abstract: Compression of image data from Burst Observer and Optical Transient Exploring System (BOOTES) is discussed. BOOTES project is an international robotic telescope for optical transient of gamma ray bursts (GRB). The statistical distribution of image functions in astronomical images from wide field and deep sky cameras is compared with Gaussian and Laplacean probability density function (pdj). The comparison of two irrelevancy reduction methods is presented from a scientific (astrometry and photometry) point of view. First one is based on a statistical approach to data compression and it is suggested from the Karhunen-Loeve transform (KLT) with uniform quantization in spectral domain. Second technique is derived from wavelet decomposition with adaptive choosing of used mother wavelet.
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4,331
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Please write an abstract with title: New Hybrid Model of Power Transformer Fault Classification using C-Set & MFCM — MCSVM, and key words: Mathematical models, Clustering algorithms, Analytical models, Training, Support vector machines, Standards, Partial discharges. Abstract: This paper aims to increase the diagnosis accuracy of fault classification of power transformers by introducing a new off-line hybrid model based on a combination subset of set method (C-set) & modified fuzzy C-mean algorithm (MFCM) and the optimizable multiclass-SVM (MCSVM). The innovation in this paper is shown in terms of solving the predicaments of outliers, boundary proportion, and unequal data existed in both traditional and intelligence models. Taking into consideration the closeness of dissolved gas analysis (DGA) data, the C-set method is implemented to subset the DGA data samples based on their type of faults into unrepeated subsets. Then, the MFCM is used for removing outliers from DGA samples by combining highly similar data of every subset into the same cluster to obtain the optimized training data(OTD) set. It is also used to minimize dimensionality of DGA samples and the uncertainty of the transformer condition monitoring. After that, the optimized MCSVM is trained by using the (OTD). The proposed model diagnosis accuracy is 93.3 %. The obtained results indicate that our model significantly improves the fault identification accuracy in power transformers when compared with other conventional and intelligence models.
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Please write an abstract with title: New, closed-form compact model for the cyclostationary noise and LS conversion behaviour of RF junction diodes, and key words: Radio frequency, Diodes, Circuit noise, Parasitic capacitance, Closed-form solution, Equations, Admittance, Noise generators, Circuit simulation, RF signals. Abstract: Classical bipolar junction theory is applied to the determination of closed-form expressions for the conversion admittance matrix and the cyclostationary noise characterization of pn diodes for RF applications. The compact model applies to both long- and short-side junctions, and is validated against physics-based simulations.
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Please write an abstract with title: Specification of a Managing Agent of Emergent Serious Games for a Smart Classroom, and key words: Hardware, Adaptation models, IEEE transactions, Middleware. Abstract: This article presents the specification of a Managing Agent of emergent serious games for a smart classroom. The Managing Agent of Emergent Serious Games is a manager of emergent serious games, which seeks to adapt emergent serious games to the subject that is developed in the smart classroom, with the aim of motivating the acquisition of knowledge and skills in students during their learning processes. The introduction of emergent serious games in a smart classroom allows incorporating a new type of teaching resource in the learning dynamic, which allows enriching with new strategies the learning process.
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Please write an abstract with title: FEC Implementation and Options for Short-Reach Optical Transmission, and key words: Forward error correction, Decoding, Iterative decoding, Optical buffering, Field programmable gate arrays, Floors, Adaptive optics. Abstract: We review FEC options for short-reach optical transmissions including staircase code, concatenated staircase and Hamming code, QC-LDPC code, and LDPC convolution code. We optimize the FEC implementations employing high-throughput FPGA emulations from the aspects of decoding buffer size, fixed-point scale factor, and error floor elimination.
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Please write an abstract with title: Object Detection in Unmanned Aerial Vehicle (UAV) Images using YOLOv5 with Supervised Spatial Attention Module, and key words: Space vehicles, Measurement, Image resolution, Convolution, Computational modeling, Object detection, Autonomous aerial vehicles. Abstract: There have been various object detection models developed recently that have enabled better results in object detection. Object detection has gradually increased in computer vision with further development of application areas. Unmanned aerial vehicle (UAV) images feature smaller and more fragmented objects, as opposed to landscape images where objects occupy more space. Furthermore, rotational and measuremental factors reduce object detection accuracy. In this paper, an improved object detection framework based on YOLOv5 is proposed in order to resolve these issues. As such, this study proposes SSAM-Darknet for the detection of UAV images based on objects. SSAM-Darknet and Bi-FPN are used to extract multiscale and multilevel features from the input images. Additionally, dilated convolution and the Ada-bound optimizer are employed to enhance the proposed model in detecting the objects from UAV images. This experiment evaluates the accuracy of object detection by using VisDrone-DET. AP (Average Precision) and AR (Average Recall) metrics are proposed as a quantitative way of evaluating detection performance. The proposed model achieves an average precision of 34.32 making an increase in detection accuracy by 10% compared to other detectors.
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Please write an abstract with title: Design method for resonant inductive power transfer systems using a resistor ladder prototype, and key words: Prototypes, Equivalent circuits, Resistance, Resistors, Band-pass filters, Topology, Inductors. Abstract: This paper presents a method for finding the optimum load resistance that maximizes the power efficiency of a tuned-resonant inductive power transfer (IPT) system. In this method, the equivalent AC circuit of the IPT system is transformed to match the topology of a reference ladder prototype. This simplifies the design problem, because the ladder prototype offers intuitive and accurate closed-form approximations for the optimum load resistance and maximum power efficiency. The process is graphical in the sense that manipulations and transformations are made directly on the circuit diagram. Compared to traditional circuit analysis, the ladder prototype approach does not entail complicated systems of equations or matrix manipulations. We show the utility of our method by designing a practical IPT system.
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Please write an abstract with title: The Use of Supervised Text Classification Techniques: A Comprehensive Study, and key words: Deep learning, Support vector machines, Sentiment analysis, Machine learning algorithms, Social networking (online), Text categorization, Feature extraction. Abstract: Every second in social networking, a massive amount of feedback, comments, and posts are made, resulting in a massive increase in the social database. It's now necessary to go through enormous amounts of data to figure out how people feel about a certain company or product. Most online evaluations are published in English, but as technology and people's understanding improve, Hindi-language material is becoming more prevalent on the internet. In addition, knowing people's views about a particular item is an important component of Indian language sentiment analysis; we consider all of their thoughts to be equally valid. To boost the accuracy of our categorization, we used the Hindi language repository for general news stories from a number of news sources. Text classification accuracy was investigated using Naive Bayes and other machine learning classification techniques, as well as Random Forest, Support Vector Machines, and Logistic Regression approaches.
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Please write an abstract with title: Behavior-Driven Re-engineering for Testing the Cloud, and key words: Testing, Cloud computing, Software, Object oriented modeling, Data models, Java, Measurement. Abstract: Cloud is an emerging technology in software development by its capability using orchestration to provide composite services through implementations somewhere on the Internet. Once it is composed the services can be easily usable by diversified clients. In practice, however, each client relies on the presentation of high level features to utilize the required Service Level Agreements. On top of this, test engineer knows only these features while the implementation and the infrastructure remain hidden. Testing becomes challenging the classical and legacy testing procedure. The paper describes the importance of cloud challenges and elaborates the appropriate way like a behavior- driven model-based re-engineering to design and validate test instances with a sample scenario for testing the cloud. It also illustrates this scenario with GraphWalker model which generates test paths through a Finite State Machine through which it enables instances of domain specific language. The generated paths include forwarding inputs and assertions to validate quality of test instances. As evaluation, the tester uses an Open Source Web Application implemented in Eclipse environment with REST assured libraries. The web application setup is configured on the cloud before a testing operation is done. Then, the implemented service is deployed on Azure platform as-a Service using Microsoft Azure plugin toolkit for Eclipse to execute the test plans on specified service.
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Please write an abstract with title: A New Approach to Measure the Energy On-Board Train During Braking, and key words: Energy measurement, Rail transportation, Choppers (circuits), Voltage measurement, Current measurement, Traction motors, Integrated circuit modeling. Abstract: Measuring energy wasted during braking by trains is a nontrivial task because it is performed by power semiconductor devices that switch high current levels at a few hundred hertz. The chopped signals produced are difficult to analyze, not only for the high switching frequency but also for the high slew rate that produces even higher harmonic content. In this harsh scenario, it is challenging to guarantee an adequate level of accuracy and it could be very expensive for railway operators, who often completely renounce measuring these quantities of interest, estimating it from mechanical quantities. In a previous article, we have already faced this issue by developing an accurate technique usable offline. Here, two simplified methods with suitable accuracy levels for train energy management and easy to be implemented on train control unit are proposed. This article describes the phenomena of interest and related measurement issues. A numerical solution together with a deep analysis on the input quantities needed is presented. The methods are applied to experimental data from a measurement campaign, conducted on-board train in the northern part of Italy. Furthermore, the metrological performances of the methods are assessed by adopting as a reference the offline technique.
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Please write an abstract with title: Joint Estimation of Metal Density and Attenuation Maps With Pencil Beam XFET, and key words: Attenuation, Metals, Image reconstruction, Fluorescence, Detectors, Geometry, X-ray imaging. Abstract: X-ray fluorescence emission tomography (XFET) is an emerging imaging modality that images the spatial distribution of metal without requiring biochemical modification or radioactivity. This work investigates the joint estimation of metal and attenuation maps with a pencil-beam XFET system that allows for direct metal measurement in the absence of attenuation. Using singular value decomposition on a simplified imaging model, we show that reconstructing metal and attenuation voxels far from the detector is an ill-conditioned problem. Using simulated data, we develop and compare two image reconstruction methods for joint estimation. The first method alternates between updating the attenuation map with a separable paraboloidal surrogates algorithm and updating the metal map with a closed-form solution. The second method performs simultaneous joint estimation with conjugate gradients based on a linearized imaging model. The alternating approach outperforms the linearized approach for iron and gold numerical phantom reconstructions. Reconstructing an (8 cm)3 object containing gold concentrations of 5 mg/cm3 and an unknown beam attenuation map using the alternating approach yields an accurate gold map (NRMSE = 0.19) and attenuation map (NRMSE = 0.14). This simulation demonstrates an accurate joint reconstruction of metal and attenuation maps, from emission data, without previous knowledge of any attenuation map.
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Please write an abstract with title: Microcontroller based Automatic Sun Tracking Solar Panel, and key words: Industries, Microcontrollers, Solar energy, Solar panels, Solar radiation, Sun, Power generation. Abstract: The solar industry is a multibillion industry producing 20 GW of power and the power is not the expected power required for processing. The Sun illuminates the earth every day by irradiating an enormous amount of energy of which a majority is lost or not utilized because of the unscientific placement of solar panels. Conversion from solar energy to electrical energy is much greater when the solar panel is placed perpendicular to the sun all the time. Thus tracking the location of the sun and the position of the panel is of great significance.
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Please write an abstract with title: Smooth attitude stabilisation in prescribed time of a rigid body despite uncertainties in inertia and additive disturbances, and key words: Uncertainty, Additives, Backstepping, Automation, Attitude control, Numerical simulation, Robustness. Abstract: We consider the problem of stabilisation in predefined, finite time of the attitude of a rigid body. Inspired by classical laws in missile guidance, the proposed control law is time-varying but smooth as opposed to classical sliding-mode-based laws that are generally discontinuous, or continuous at best, and suffer from robustness issues. Through a backstepping design, and the explicit construction of a strict Lyapunov function, we are able to ensure stabilisation to a desired attitude even in the presence of uncertainties in the inertia matrix and under the effect of additive disturbances. Numerical simulations show the efficiency of the proposed controller.
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Please write an abstract with title: 6G, LIFI and WIFI Wireless Systems: Challenges, Development and Prospects, and key words: 6G mobile communication, High-speed networks, Information processing, Media, Light fidelity, Ubiquitous computing, Internet of Things. Abstract: While 5G is being deployed commercially worldwide, scientists have carried out research for 6G as well as WIFI 6G bands, and LIFI are also tested. Both advantages and disadvantages of these three wireless communication methods are focused and the respective application scenarios are described as well as the difficulties and challenges to be overcome. An integrated network system of space and earth is proposed to provide users with ubiquitous wireless network connection. Technologies and challenges required by three communication methods are sorted out and the way they can be combined and applied are analyzed through extensive research and analysis.
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Please write an abstract with title: Review on Medical Image Denoising Techniques, and key words: Image edge detection, Computed tomography, Noise reduction, Positron emission tomography, Medical diagnostic imaging, Diseases, Image denoising. Abstract: In recent times, with rapid growth in technology, medical imaging has become popular in healthcare. The impression of these improvements in the medical field has become evident that technology can able to diagnose disease in a much better way than before. Medical images play a vital role in the detection and prediction of disease but these images may tend to corrupt by some kind of noise or artifacts during the image acquisition process. The presence of noise makes images unclear, fine details and features of the original image are lost which leads to inaccurate detection of disease. Hence, different denoising methods are required to eliminate noise without losing image features (edges, corners, and other sharp structures). Researchers have already proposed different tools and techniques to reduce noise. Each technique has its merits and demerits. Hence preprocessing of medical images is a mandatory and essential process to get accurate results. This review article provides a comprehensive survey of different noises, denoising models, contrast enhancement methods, quality matrices. In addition, the main aim of this paper is to conduct a detailed analysis of various preprocessing techniques used on medical images which include Computed Tomography (CT), Magnetic Resonance images (MRI), Positron Emission Tomography (PET), 2D/3DULTRASOUND images.
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Please write an abstract with title: Analysis Machine Learning Approach and Model on Hyper Spectral (Sentinel-2) Images for Land Cover Classification: Using SVM, and key words: Support vector machines, Machine learning algorithms, Crops, Support vector machine classification, Machine learning, Spatial databases, Systems support. Abstract: The goal of this research study will be to research different machine learning algorithm via context oriented methodology with or without entropy for sub-pixel categorization utilizing Sentinel 2, multi-Spectral data extract reasonably accurate information for different land cover classes. To study the capabilities of Machine Learning Applications for Crop Identification and Use of temporal data information for crop planning in Machine Learning Algorithm this exploration will supportive to check Capability of Red Edge band to consolidate Crop phenology in crop recognizable proof. In this analysis work knowledge classification approach are going to be applied whereas getting ready land use and land covered map victimization for multi-spectral remote sensing knowledge sets (Sentinel-2/ Land sat). The data sets to be used in this research work will be fine spatial resolution data, to ensure classify approaches towards spatial data set and classification.
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Please write an abstract with title: Edge node deployment based on Clustering of Internet of things terminal attributes, and key words: Performance evaluation, Energy consumption, Power supplies, Network topology, Computational modeling, Merging, Topology. Abstract: With the rapid development of the Internet of Things technology, the performance requirements for data transmission between terminal devices are getting higher and higher. However, the edge computing generated by this situation can well allocate data computing resources, realize more efficient and faster data processing and upload to the cloud. This paper proposes and implements an edge node deployment method based on Clustering of Internet of things terminal attributes to build cluster networks. Firstly, we design an algorithm of finding the deployment location of edge computing nodes by merging clustering. Then, factors such as the power supply of the devices, the amount of data, and energy remaining of edge computing nodes are comprehensively considered in terms of using clustering method. Finally, the resulting deployment topology network is optimized in the case of unbalanced and unstable data distribution of these nodes. The simulation experiment verifies that the method can accurately and reliably obtain the position of the edge computing nodes, and generate a clustering topology network under the condition of ensuring the balance.
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Please write an abstract with title: Estimation of the Parameters of Exponentially Damped Sinusoidal Signals, and key words: Damping, Estimation error, Simulation, Computational modeling, Linear regression, Europe, Generators. Abstract: The problems of identifying the parameters (frequency, damping factor, amplitude and phase) of exponentially damped sinusoidal signals with constant parameters are con-sidered. The signal is represented as the output of a linear generator, the parameters of the sinusoidal signal (amplitude, phase, damping factor and frequency) are unknown. The main idea is to apply the Jordan waveform and delay to parameterize the signal and obtain a linear regression model. The performance of the algorithms considered in the article is illustrated by computer modeling.
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Please write an abstract with title: Research and Application of Cloud Computing in Power Consumption Information Acquisition System, and key words: Computers, Seminars, Cloud computing, Power demand, Distribution networks, Computer architecture, Transforms. Abstract: With the development of the power Internet of things, higher requirements are imposed on the data processing of distribution network. The traditional Oracle database can no longer withstand the increasing data pressure of the power consumption information acquisition system, so it is urgent to alter the system. This paper uses cloud computing technology to transform the power consumption information acquisition system in distribution network. By setting business process verification scenarios to simulate the use of electricity information collection and storage experiments, the feasibility of business migration to the cloud and the cloud platform’s performance advantage are verified. Moreover, the security of the cloud platform architecture is analyzed, and the results show that the cloud computing technology can provide a certain level of support for the existing power consumption information acquisition system.
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Please write an abstract with title: On the Eurasian SubMillimeter Telescopes Project (ESMT), and key words: Telescopes, Laser radar, Mirrors, Optical surface waves, Radar tracking, Measurement by laser beam, Optics. Abstract: The new challenges in the submillimeter astronomy call for the instruments combining high sensitivity and angular resolution, wide field of view, and multiwavelength (multicolor) spectral range. New single dish mm/submm telescopes in Eurasia are in high demand as well as their inclusion in the Event Horizon Telescope (EHT) VLBI network. The astroclimate studies aimed at the selection of the appropriate Eurasian site for a new mm/submm telescope began in 2012. The ESMT concept suggests the construction of three new mm/submm radio telescopes of 15-21 m class to be built in Suffa (Aktashtau), Uzbekistan, in Russia, and in Tibet, China to cover frequency bands up to 230 GHz (Russia), up to 350 GHz (Uzbekistan) and up to 1.5 THz (China). In the ESMT concept European ALMA antennas are taken as a starting point, increased their diameter to 21m, optimized an optical layout and the truss frame, supplemented an active surface and tertiary optics, including adaptive optics. Variants of the ESMT optical layout and tertiary optics are presented, which make it possible to maintain a compact dilution cryostat with KID-array camera in a vertical position during operation of the telescope to ensure its operability. The characteristics of the image quality of ESMT with a large-format KID-array camera in a field of view up to 10'×10' are estimated. The possibilities of applying active optics with the use of fast holography, precise laser trackers and radars and adaptive optics with a tilted tertiary mirror are considered.
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Please write an abstract with title: Feasibility of Intelligent Reflecting Surfaces to Combine Terrestrial and Non‐terrestrial Networks, and key words: Communications technology, Wireless networks, Telecommunication network reliability, Satellites, Reflection, Industries, Reflector antennas. Abstract: Third‐generation partnership project (3GPP) in Release 17 is working on the standardization of non‐terrestrial networks (NTN) to enable 5G‐based terrestrial networks to support NTN. Based on an initial version of Release 17, the NTN will consist of low earth orbit (LEO) satellites constellation, whereas the unmanned aerial vehicles (UAVs) and high‐altitude platforms (HAPs) are considered as a special use case of NTN networks. Similar to the global positioning system (GPS), the NTN‐based signals are unable to provide indoor coverage, as the signals from these satellites are attenuated and scattered by roofs, walls, etc. Moreover, the power and delay are the critical factors that restrict a cellular‐enabled mobile handset to obtain reliability, seamless coverage, and low latency, while relying on NTN networks. Recent literature has proven that intelligent reflecting surfaces (IRSs) are much effective in tunning wireless signals to improve spectral and energy efficiencies, achieving seamless coverage, and faster data rates. The key feature of an IRS is to enhance the coverage of a wireless network by providing an additional channel gain only by reflecting the signals. In this chapter, we have carried out an analysis, based on recent literature, to study the feasibility of using IRSs in enabling the co‐existence of NTN in terrestrial networks environment.
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Please write an abstract with title: Predictive plus Feedforward Controller for an Inverter with Voltage Support Function, and key words: Electrical engineering, Voltage measurement, Computational modeling, Simulation, Measurement uncertainty, Predictive models, Inverters. Abstract: In this paper, a Distributed Generation System (DGS) with voltage support capability is studied, in order to meet the requirements of additional ancillary services controllers with an improved performance are needed. The proposed controller is composed of two elements: on one hand a Model Predictive Controller (MPC) which is intended to calculate the control action which minimizes the current tracking error and the control effort; on the other hand, a feedforward term is employed for the purpose of rejecting the effect of the voltage at the point of common coupling (PCC), which is considered a measurable disturbance of the system. The system under study comprises a three-phase inverter with an LCL output filter connected to the grid. Simulation results are presented to validate the performance of the system under overvoltage and undervoltage scenarios.
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Please write an abstract with title: Improved Automated CASH Optimization with Tree Parzen Estimators for Class Imbalance Problems, and key words: Machine learning algorithms, Conferences, Machine learning, Data science, Classification algorithms, Bayes methods, Task analysis. Abstract: The imbalanced classification problem is very relevant in both academic and industrial applications. The task of finding the best machine learning model to use for a specific imbalanced dataset is complicated due to a large number of existing algorithms, each with its own hyperparameters. The Combined Algorithm Selection and Hyperparameter optimization (CASH) has been introduced to tackle both aspects at the same time. However, CASH has not been studied in detail in the class imbalance domain, where the best combination of resampling technique and classification algorithm is searched for, together with their optimized hyperparameters. Thus, we target the CASH problem for imbalanced classification. We experiment with a search space of 5 classification algorithms, 21 resampling approaches and 64 relevant hyperparameters in total. Moreover, we investigate performance of 2 well-known optimization approaches: Random search and Tree Parzen Estimators approach which is a kind of Bayesian optimization. For comparison, we also perform grid search on all combinations of resampling techniques and classification algorithms with their default hyperparameters. Our experimental results show that a Bayesian optimization approach outperforms the other approaches for CASH in this application domain.
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Please write an abstract with title: Association and Caching in Relay-Assisted mmWave Networks: A Stochastic Geometry Perspective, and key words: Relays, Optimization, Approximation algorithms, Cache storage, Stochastic processes, Throughput, Wireless networks. Abstract: Limited backhaul bandwidth and blockage effects are two main factors limiting the practical deployment of millimeter wave (mmWave) networks. To tackle these issues, we study the feasibility of relaying as well as caching in mmWave networks. A user association and relaying (UAR) criterion dependent on both caching status and maximum biased received power is proposed by considering the spatial correlation caused by the coexistence of base stations (BSs) and relay nodes (RNs). Using stochastic geometry tools, we decouple the UAR and caching placement issues by analyzing the relationship between UAR probabilities and caching placement probabilities. We then optimize the formulated caching placement problem based on polyblock outer approximation by exploiting the monotonic property in the general case and utilizing convex optimization in the noise-limited case. Accordingly, we propose a BS and RN selection algorithm where caching status at BSs and maximum biased received power are jointly considered. Experimental results demonstrate a significant enhancement of backhaul offloading using the proposed algorithms, and show that deploying more RNs and increasing cache size in mmWave networks is a more cost-effective alternative than increasing BS density to achieve similar backhaul offloading performance.
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Please write an abstract with title: Energy-Efficient Multi-UAV-Enabled Multiaccess Edge Computing Incorporating NOMA, and key words: NOMA, Servers, Energy consumption, Task analysis, Resource management, Internet of Things, Edge computing. Abstract: Multiaccess edge computing (MEC) is regarded as a promising solution to overcome the limit on the computation capacity of mobile devices. This article investigates an energy-efficient unmanned aerial vehicle (UAV)-enabled MEC framework incorporating nonorthogonal multiple access (NOMA), where multiple UAVs are deployed as edge servers to provide computation assistance to terrestrial users and NOMA is adopted to reduce the energy consumption of task offloading. A utility is formed to mathematically evaluate the weighted energy cost of the system. Due to the coupling of parameters, the minimization of utility is a highly nonconvex problem and therefore, the problem is decomposed into two more tractable subproblems, i.e., the optimal allocation of radio and computation resources given UAV trajectories, and the trajectory planning based on given resource allocation schemes. These two problems are converted to convex ones via successive convex approximation (SCA) and quadratic approximation, respectively. Then, an efficient iterative algorithm is proposed where these two subproblems are alternately solved to gradually approach the optimal resource management of the proposed system. Sufficient numerical results show that our proposed strategy has a remarkable advantage over existing systems in terms of energy efficiency.
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Please write an abstract with title: Frequency Characteristics of Buck Converter Control Systems with Second-order Sliding Mode, and key words: Industrial electronics, Analytical models, Buck converters, Stability criteria, Transfer functions, Frequency conversion, Control systems. Abstract: In this paper, the frequency analysis of second-order sliding mode (SM) controlled buck converters is investigated by utilizing the description function (DF) approach. The transfer function of the buck converter is established on the basis of the small signal model. Taking the commonly-used super-twisting algorithm as an example, a second-order SM controller is designed, which consists of two nonlinear components. Then by adopting the DF approach, the linearized counterparts of the both can be further deduced, following the block diagram of the whole closed-loop control system. Based on the Nyquist stability criterion, the system stability is studied, which proves the inevitable existence of periodic oscillations caused by the nonlinearity of the controller. Meanwhile, the influence of the controller parameters with the frequency characteristics is investigated. Simulations validate this paper.
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Please write an abstract with title: Computer-aided Geometric Modeling of Plant Cell Shape and Design of Its Topological Retrieval Algorithms, and key words: Shape, Faces, Topology, Computational modeling, Biological system modeling, Data structures, Image color analysis. Abstract: Using the knowledge of information technology and physical mechanics to simulate the evolution of plant cell shapes is helpful to explore the mechanism of plant tissue and organ formation. However, the traditional numerical modeling based on curves and surfaces is difficult to accurately locate a geometric fragment of cell shape, resulting in the inability to analyze the stress and strain of the fragment freely. In this study, a plant cell shape is firstly decomposed into a body, faces, edges, and vertexes from top to bottom using the n-dimensional generalized mapping theory. Then, the 1-, 2-and 3-dimensional topologies of the cell shape are constructed by combining these topologies from bottom to top using the “half-edge” structure of 0-dimensional topology, and the corresponding retrieval algorithms are designed. Finally, the program is achieved by the C++ programming language and the OpenGL graphics library. The experimental results show that users could not only retrieve the geometric units of cell shape freely, but also highlight the query results in the program through the query interface of this program. The results of this study can provide an automatic topological retrieval of a cell shape for the elastic mechanical modeling of cell shape deformation.
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Please write an abstract with title: Numerical Investigation to Improve the Performance of Induction Heating Oven for Tyre Mould Preheating, and key words: Coils, Temperature distribution, Electromagnetic heating, Ovens, Simulation, Atmospheric modeling, Air gaps. Abstract: This paper presents a numerical analysis of an industrial-scale induction heating oven to improve heat transfer performance for applications in the tyre manufacturing industry. Tyre mould preheating is a vital step in the tyre manufacturing process, for which the local industry is currently using conventional heating techniques. Research has shown that induction heating has the potential to significantly reduce the heating time and the energy use of the tyre mould preheating. However, some limitations in obtaining the required temperature profiles have prevented the local industry in moving toward induction heating. Hence, this research focused on using finite element analysis to study the induction heating process to propose an improved oven unit for tyre mould preheating. The simulation was conducted on a simplified and scaled-down model of a tyre mould to study the effects of key parameters. The simulation results showed that. The pancake type coils are recommended for the application and the maximum Ohmic losses could be obtained when the coil air gap is 7-8 mm.
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Please write an abstract with title: Sharing Light and Knowledge to Underdeveloped Village with Portable House Lighting System, and key words: community, humanity, portable lighting, education, knowledge sharing. Abstract: The province of Banten on western end of Java is one of the provinces with most visible disparity in the area development, in the southern part, the terrain is mountainous with dry valleys, this condition led to being the poverty area. The Cahaya Kebudiluhuran or “Noble Light” Project aims to implement the ideals of intelligent and noble humanity through the use of technology for the benefit on the greater community. The main target community is the Menes village in Pandeglang Regency, among the poorest region in otherwise flourishing Java's other regions. The first phase of Noble Light Project implementation consists of distributing and installation of forty battery-operated portable home lighting equipment for 40 houses, and one battery charging station located at the Village Office Hall. The Portable House Lighting Unit consists of a 12 V, 45 Ah battery, 1.5 W LED lights and regulator/ control panel capable of 67.5 hour life cycle. Laboratory test for the unit performance shows that for normal 11-hours night-time use from 6 PM to 5 AM the house unit can provide lighting for 5 to 6 days.
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Please write an abstract with title: Internet of Things Applied to Hydraulics, and key words: Hydraulic systems, Temperature sensors, Internet of Things, Monitoring, Companies, Mechanical sensors. Abstract: This work presents a technology-based innovation in the teaching and learning of electronics. The project is an academic competition proposed by the company HydraForce with the aim of developing an Internet of Things application. In the activity a group of students must develop a system with several sensors for to monitoring hydraulic machines employed in agriculture in order to improve their performance and consequently generating savings in resources or other benefits for the farmer or the machine manufacturer. The project is carried out over a semester and has the tutorship of two professors and professionals from the proposing company, with an award for the best work developed.
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Please write an abstract with title: The Use of Chatbots in Digital Business Transformation: A Systematic Literature Review, and key words: Chatbots, Business, Bibliometrics, Bibliographies, Systematics, Australia, Databases. Abstract: The research on chatbots has gained momentum over the past few years. Academics and practitioners investigate how these tools for communication with customers or internal team can be improved in terms of their performance, acceptance, and deployment. Although there is a plethora of recent studies available, not all of them deal with the digital business transformation implications of chatbots. The main aim of the research presented in this paper was to conduct a systematic literature review of high-quality journal research papers in order to summarise the current state of research on chatbots, identify their role in digital business transformation and suggest the areas warranting further attention. 74 papers were included in the research. Topical (focus and applications), methodological (methods used, sample size, sample type, and countries studied) and bibliometric (publication outlet, citations, and Altmetric Attention Score) aspects are evaluated and described. Scholars and practitioners can use the results to identify topics, areas, and applications that are intensely discussed in the literature and require further attention, select a methodology for their research that is well established in the field or is emerging, identify the most influential publications not to be missed in their research or identify publication outlets for publishing their research on chatbots.
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Please write an abstract with title: Bifurcation Suppression of Peak Current Boost PFC Converter, and key words: Chaos, PI control, Mechatronics, Perturbation methods, Simulation, Bifurcation, Power factor correction. Abstract: In order to analyze the nonlinear bifurcation phenomenon of Boost power factor correction (PFC-Power Factor Correction) converter with DC charging pile front stage peak current control under fast time scale, the control method is added to effectively suppress the bifurcation phenomenon. Firstly, the flicker mapping model of the converter is established, and the intermittent bifurcation and chaos phenomena of the inductance current of the system are reproduced through the numerical simulation results of the model. The control method is added to suppress the bifurcation phenomenon, so that the system is always stable in the single-period state, and the control method of Self-tuning PI control resonance perturbation is adopted. The simulation results show that the system has high PF value and better robustness while effectively suppressing bifurcation and chaos, and the algorithm is easy to implement in engineering applications.
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Please write an abstract with title: Terrain analysis using radar shape-from-shading, and key words: Surface topography, Surface reconstruction, Reflectivity, Radar imaging, Image reconstruction, Maximum likelihood detection, Robustness, Statistics, Synthetic aperture radar, Maximum likelihood estimation. Abstract: This paper develops a maximum a posteriori (MAP) probability estimation framework for shape-from-shading (SFS) from synthetic aperture radar (SAR) images. The aim is to use this method to reconstruct surface topography from a single radar image of relatively complex terrain. Our MAP framework makes explicit how the recovery of local surface orientation depends on the whereabouts of terrain edge features and the available radar reflectance information. To apply the resulting process to real world radar data, we require probabilistic models for the appearance of terrain features and the relationship between the orientation of surface normals and the radar reflectance. We show that the SAR data can be modeled using a Rayleigh-Bessel distribution and use this distribution to develop a maximum likelihood algorithm for detecting and labeling terrain edge features. Moreover, we show how robust statistics can be used to estimate the characteristic parameters of this distribution. We also develop an empirical model for the SAR reflectance function. Using the reflectance model, we perform Lambertian correction so that a conventional SFS algorithm can be applied to the radar data. The initial surface normal direction is constrained to point in the direction of the nearest ridge or ravine feature. Each surface normal must fall within a conical envelope whose axis is in the direction of the radar illuminant. The extent of the envelope depends on the corrected radar reflectance and the variance of the radar signal statistics. We explore various ways of smoothing the field of surface normals using robust statistics. Finally, we show how to reconstruct the terrain surface from the smoothed field of surface normal vectors. The proposed algorithm is applied to various SAR data sets containing relatively complex terrain structure.
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Please write an abstract with title: Database Interface Application Based on ODBC Development, and key words: Computer science, Costs, Databases, Computational modeling, Big Data applications, Software, Communications technology. Abstract: In this paper, the structure and application principle of ODBC and the basic method and idea of developing data application program based on ODBC are described in detail. Combined with a concrete example, this paper describes how to develop the simulation software of the dual channel amplitude ratio direction finder, and introduces in detail the link between the application program of the simulation software and the database, the concrete realization of the main button and the realization of key technologies. From the development of the program, the application of ODBC development applications, high development efficiency, strong compatibility, short development cycle, low cost, easy to achieve. It has strong operability and practicability and is widely used in small simulation software.
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Please write an abstract with title: Uniform Asymptotic Stabilization of Affine Periodic Discrete-Time Systems, and key words: Time-varying systems, Closed loop systems, Trajectory, Lyapunov methods, Discrete-time systems, Asymptotic stability, Damping. Abstract: In this article, we study the problem of asymptotic stabilization for nonlinear affine discrete-time control systems with periodic coefficients via state feedback. It is supposed that the origin of the free dynamic system is (non-asymptotically) stable. The method for constructing a damping control is extended from time-invariant systems to time varying periodic affine discrete-time systems. This method is based on the Krasovsky-La Salle invariance principle for periodic systems. Using this approach, we obtain sufficient conditions for uniform local and global asymptotic stabilization for those systems.
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Please write an abstract with title: Gas identification by wavelet transform-based fast feature extraction and support vector machine from temperature modulated semiconductor gas sensors, and key words: Feature extraction, Support vector machines, Temperature sensors, Gas detectors, Agriculture, Gas industry, Stability, Pattern recognition, Discrete wavelet transforms, Thermal decomposition. Abstract: Semiconductor gas sensors are widely applied in agriculture and industrial fields for its low price and high sensitivity. For the physical shortcomings of gas sensors such as cross-sensitivity and lack of the stability, it is difficult to get steady and accurate result. In this paper we present a new strategy to extract features from the response of a thermally modulated semiconductor gas sensor, combined with support vector machine (SVM) pattern recognition method for gas identification. A signal pre-processing method and wavelet decomposition transformation (DWT) were applied to extract features of a signal thermal modulated semiconductor gas sensor's response curves. Experiment result shows that the proposed method can perform well in discrimination of CO, H/sub 2/ their mixtures than traditional neural network.
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4,366
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Please write an abstract with title: Energy Efficiency Comparison for Full-Duplex DF and AF Relaying Protocols, and key words: Relays, Protocols, Power demand, Electronic mail, Energy efficiency, Interference cancellation, Wireless networks. Abstract: In this paper, the energy efficiency (EE) of full-duplex (FD) two-hop relay system with decode-and-forward (DF) and amplify-and-forward (AF) relaying protocols is studied. The residual self-interference (RSI) is modeled as a linear function of relay transmit power first. Then, with the constant transmission rate, the EE maximization problem is transformed into transmit power minimization problem and the minimum transmit power consumptions of the DF and AF protocols are obtained. Furthermore, the EE comparison of the DF and AF protocols is given with the minimum transmit power consumption. The simulation results are given to verify the theoretical EE analysis and comparison.
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4,367
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Please write an abstract with title: Tensor Decompositions in Wireless Communications and MIMO Radar, and key words: Wireless communication, Analytical models, Tensors, Parameter estimation, Algebra, MIMO radar, Channel estimation. Abstract: The emergence of big data and the multidimensional nature of wireless communication signals present significant opportunities for exploiting the versatility of tensor decompositions in associated data analysis and signal processing. The uniqueness of tensor decompositions, unlike matrix-based methods, can be guaranteed under very mild and natural conditions. Harnessing the power of multilinear algebra through tensor analysis in wireless signal processing, channel modeling, and parametric channel estimation provides greater flexibility in the choice of constraints on data properties and permits extraction of more general latent data components than matrix-based methods. Tensor analysis has also found applications in Multiple-Input Multiple-Output (MIMO) radar because of its ability to exploit the inherent higher-dimensional signal structures therein. In this paper, we provide a broad overview of tensor analysis in wireless communications and MIMO radar. More specifically, we cover topics including basic tensor operations, common tensor decompositions via canonical polyadic and Tucker factorization models, wireless communications applications ranging from blind symbol recovery to channel parameter estimation, and transmit beamspace design and target parameter estimation in MIMO radar.
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4,368
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Please write an abstract with title: A hybrid nanorobotic manipulation system integrated with nanorobotic manipulators inside scanning and transmission electron microscopes, and key words: Scanning electron microscopy, Transmission electron microscopy, Atomic force microscopy, Nanoscale devices, Manipulators, Piezoelectric devices, Carbon nanotubes, Scanning probe microscopy, Tunneling, Cities and towns. Abstract: A hybrid nanorobotic manipulation system, which is integrated with a nanorobotic manipulator inside a transmission electron microscope (TEM) and nanorobotic manipulators inside a scanning electron microscope (SEM), is presented. The TEM nanomanipulator has been constructed with 4 multi-layer piezoelectric devices for driving in 3 translational degrees of freedoms (DOFs) and a passive 3-DOF sample stage driven by SEM nanorobotic manipulators. The nanomanipulation system has high enough resolution to identify nano-scale objects, e.g., carbon nanotube (CNT), due to the adoption of a TEM, and efficient and rapid nanomanipulations have been realized within wide enough working space of the SEM nanomanipulators.
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4,369
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Please write an abstract with title: A Tiger's Speed, an Elephant's Memory: Holographic Storage Ready for Market, and key words: Holography, Optical recording, Holographic optical components, Optical materials, Material storage, DVD, Optical sensors, Costs, Consumer products, Dinosaurs. Abstract: Emerging holographic technologies have progressed to the point where companies worldwide, such as Japan-based Optware Corporation and InPhase Technologies in the US, are projecting consumer products will be on the market within a year.
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4,370
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Please write an abstract with title: High contrast at small separation – II. Impact on the dark hole of a realistic optical set-up with two deformable mirrors, and key words: instrumentation: miscellaneous, techniques: high angular resolution, techniques: miscellaneous, methods: numerical, planetary systems. Abstract: Future large space- or ground-based telescopes will offer the resolution and sensitivity to probe the habitable zone of a large sample of nearby stars for exo-Earth imaging. To this end, such facilities are expected to be equipped with a high-contrast instrument to efficiently suppress the light from an observed star to image these close-in companions. These observatories will include features such as segmented primary mirrors, secondary mirrors, and struts, leading to diffraction effects on the star image that will limit the instrument contrast. To overcome these constraints, a promising method consists in combining coronagraphy and wavefront shaping to reduce starlight at small separations and generate a dark region within the image to enhance the exoplanet signal. We aim to study the limitations of this combination when observing short-orbit planets. Our analysis is focused on SPEED, the Nice test bed with coronagraphy, wavefront shaping with deformable mirrors (DMs), and complex telescope aperture shape to determine the main realistic parameters that limit contrast at small separations. We develop an end-to-end simulator of this bench with Fresnel propagation effects to study the impact of large phase and amplitude errors from the test-bed optical components and defects from the wavefront shaping system on the final image contrast. We numerically show that the DM finite stroke and non-functional actuators, coronagraph manufacturing errors, and near-focal-plane phase errors represent the major limitations for high-contrast imaging of exoplanets at small separations. We also show that a carefully defined optical set-up opens the path to high contrast at small separation.
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4,371
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Please write an abstract with title: Optimization of Linear Antenna Array Thinning using Binary Genetic Algorithm (BGA), and key words: Geometry, Directive antennas, Turning, Market research, Linear antenna arrays, Reliability, Optimization. Abstract: To remove the interferences outside the main beam antenna array of low sidelobe level is required. There are many techniques to produce low sidelobe level. And one of them is excitation tapering at each element of the array. In this paper elements of the linear array are thinned randomly to suppress the sidelobe level using binary Genetic Algorithm (BGA). An array of linear geometry has been considered and then randomly the elements are turned ON/OFF. And the reduced results of the sidelobe level are compared with equally spaced elements linear antenna array of fifty elements.
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4,372
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Please write an abstract with title: Siamese Generative Adversarial Predicting Network for Extremely Sparse Data in Recommendation System, and key words: Training, Collaborative filtering, Estimation, Predictive models, Data models, Sparse matrices. Abstract: In the recommendation system, user-item preferences are described by a High-Dimensional and Sparse (HiDS) matrix. Collaborative Filtering (CF)-based models have been widely adopted to solve unknown entries estimation. However, a CF-based model does not take the data distribution characteristic of an HiDS matrix into account, thereby its representation ability limited. To address this issue, this paper proposes to build a Siamese Generative Adversarial Predicting Network (SGAPN) to estimate the unknown entries in an HiDS matrix. Firstly, we build a model to learn the data distribution characteristic of an HiDS matrix. Secondly, based on the learned data distribution and observed entries, we build a model to estimate the unknown entries. Compared with the CF-based model, our model takes the data distribution of an HiDS matrix into account to address the unknown entries estimation. Experimental results over four HiDS matrices generated by industrial applications demonstrate that compared with several state-of-the-art models, the proposed model achieves competitive prediction accuracy.
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Please write an abstract with title: FPGA-accelerated Agent-Based Simulation for COVID-19, and key words: COVID-19, Epidemics, Adaptation models, Sociology, Graphics processing units, Predictive models, Central Processing Unit. Abstract: Agent-based models (ABMs) can provide realistic dynamics for epidemics at the individual level so that users can observe and predict the spreading pattern and the effectiveness of intervention over time and space. This paper proposes an FPGA-based accelerator for agent-based epidemic modeling for COVID-19. The optimizations enabling the effective acceleration of the simulation procedure are presented. The key idea is to partition the calculation properly to decouple the on-chip resource usage from the population size. Also, an algorithmic adaptation is proposed to reduce the latency caused by conditional branches within loops. An experimental implementation on an Intel Arria 10 GX 10AX115S2F45I1SG FPGA running at 240MHz achieves 2.2 and 1.9 times speed-up respectively over a CPU reference using 10 cores on an Intel Xeon Gold 6230 CPU and a GPU reference on an Nvidia GeForce RTX 2080 Ti GPU.
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4,374
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Please write an abstract with title: Multilevel annotation of speech signals using weighted finite state transducers, and key words: Transducers, Speech synthesis, Synthesizers, Natural languages, Speech recognition, Speech processing, Signal processing, Relational databases, Testing, Performance analysis. Abstract: The purpose of this work was the development of a set of tools to automate the process of multilevel annotation of speech signals, preserving the alignments of the utterance's different levels of the linguistic representation. Our goal is to build speech databases, using speech from non professional speakers with multilevel relational annotations, that can be used for the development of concatenative-based text-to-speech synthesizers or for training and testing statistical models. The method is based on the linguistic analysis of the transcription of the spoken material performed by a TTS system. The predicted phone sequence is then compared with the sequence produced by the speaker. The problem of aligning these two sequences is solved in a language-independent way using Weighted Finite State Transducers. After the alignment, a re-synchronization procedure is applied to the remaining levels to put them in agreement with the spoken utterance.
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4,375
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Please write an abstract with title: Assessment of image quality with a fast fully 3D reconstruction algorithm, and key words: Image quality, Image reconstruction, Positron emission tomography, Imaging phantoms, Noise level, Computational efficiency, Image representation, Grid computing, Maximum likelihood detection, Whole-body PET. Abstract: True three-dimensional (3D) reconstructions from fully 3D positron emission tomography (PET) data yield high-quality images but at a high computational cost. Image representation using three-dimensional spherically-symmetric basis functions on a body-centered cubic (BCC) grid, as opposed to a simple cubic (SC) grid, can reduce the computational demands of a 3D approach without compromising image quality by reducing the number of image elements to be reconstructed. The goal of this study was to determine if the image quality improvements predicted for the 3D row action maximum likelihood algorithm (RAMLA) over 2.5D RAMLA after Fourier rebinning (FORE) would be seen with clinical PET data. Torso phantom, whole-body patient, and brain patient studies were used in this analysis. Data were corrected for detector efficiency, scatter, and randoms prior to reconstruction. Attenuation effects were either incorporated into the system model or pre-corrected prior to reconstruction. Higher contrast at comparable noise levels (or lower noise for comparable contrast) are seen with 3D RAMLA (SC or BCC grid) for both phantom and patient data. The brain patient data show improved axial resolution with 3D RAMLA, where the degradation in resolution with FORE is eliminated. Application of a fully 3D reconstruction algorithm is possible in clinically reasonable times.
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4,376
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Please write an abstract with title: Developing Data-Driven Approaches for Traffic Density Estimation Using Connected Vehicle Data, and key words: Estimation, Sensors, Detectors, Mathematical model, Sensor fusion, Data models, Connected vehicles. Abstract: This paper introduces novel approaches for the estimation of the traffic stream density. First, an artificial neural network (ANN) data-driven approach is developed to estimate the level of market penetration (LMP) of connected vehicles at two fixed locations. Then, the estimated values are used as inputs to a Kalman filter (KF) approach to estimate the vehicle count between these two locations. Second, three data-driven approaches are developed to directly estimate the vehicle count using only connected vehicle data, an ANN, a k-nearest neighbor (k-NN), and a random forest (RF). A congested signalized roadway in downtown Blacksburg, Virginia, is used to test and compare the performance of the estimation approaches. Results demonstrate that the ANN approach produces reasonable errors in estimating the LMPs; however, integrating the ANN with the KF results in larger errors than the errors produced from using the KF with a predefined fixed average value obtained from historical data. The results also demonstrate that the data-driven approaches provide accurate vehicle count estimates, with the ANN being the most accurate of the three approaches. Lastly, the paper compares the three developed data-driven approaches with model-driven approaches (i.e., KF), showing that the ANN outperforms all other approaches. However, taking into consideration that the difference is not large, the computational time needed to train the ANN, the large amount of data needed, and the uncertainty in the performance when new traffic behaviors are observed (e.g., incidents), the use of the KF approach is recommended in the estimation of traffic stream density due to its simplicity and applicability in the field.
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4,377
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Please write an abstract with title: A heuristic approach for design of FIR filters with SP2 coefficients, and key words: Finite impulse response filter, Linear programming, Frequency response, Cutoff frequency, NP-hard problem, Optimization methods, Nonlinear filters, Passband, Band pass filters, Vectors. Abstract: Since FIR filters can easily obtain a linear phase property, they are highly useful in many fields. In this work, we consider the design problems of linear phase FIR filter with signed power of two (SP2) coefficients. When the total number of non-zero SP2 terms is given for the design problem, we have to determine the number of nonzero SP2 terms allocated to each filter coefficient respectively while keeping the total number. However, it is considered that this problem is one of the NP-hard problems. Hence, several heuristic methods have been developed for this allocation problem. We propose a new heuristic method for this problem comparing it with traditional heuristic method through several numerical experiments.
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4,378
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Please write an abstract with title: Integrated scalable continuously tunable variable optical delay lines (invited), and key words: Integrated optics, Delay lines, Optical ring resonators, Optical buffering, Optical filters, Propagation delay, Optical waveguides, Optical switches, Delay effects, Communication switching. Abstract: A wide-tuning-range optical delay line is demonstrated in high (2%) index contrast waveguides. This device integrates 4-stage ring resonator all-pass filters (APFs) with cascaded fixed spiral-type delay waveguides; each fixed delay path varies in length by a factor of 2 from the previous stage. A 2/spl times/2 switch separates each fixed delay and the tunable parts of the delay line. The APFs allow for continuous delay tuning. This device enables coherent switching and continuous tuning ranges greater than 2.56 ns.
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4,379
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Please write an abstract with title: Research on Neutral Point Grounding Resistance Selection of Power Plant Auxiliary System, and key words: Resistance, Analytical models, Grounding, Focusing, Power systems, Voltage control, Power generation. Abstract: In order to resolve the single phase grounding of power plant auxiliary system, the neutral point grounded with a small resistance is an effective means, which can obvious reduced the amplitude and duration of the system overvoltage, According to an auxiliary power system of pumped storage power plant situation, this paper takes the small resistance grounding scheme to study the advantages of the low resistance grounding method of the auxiliary power grounding system, focusing on the selection of neutral point resistance. Through theoretical analysis and simulation calculation, the following conclusions are drawn. The simulation analysis shows that the change of the grounding point transition resistance value has a great influence on the grounding point fault current and neutral point voltage in the low resistance grounding system, which is convenient for fault analysis and search. When the total capacitance current of the system is 80 A, the neutral grounding resistance of the 10 kV auxiliary power system should be 10Ω.
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4,380
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Please write an abstract with title: Application of fuzzy theory on gas collector control, and key words: Fuzzy control, Hysteresis, Gas industry, Production, Ovens, Couplings, Mathematics, Mathematical model, Pressure control, Pollution. Abstract: Fuzzy control technology is a practical alternative for the nonlinear, big inertia and big hysteresis plant. In industrial production, the pressure of coke oven gas collector is nonlinear and has more strong couple property change parameter essentially. It is highly impossible to describe the course that it changes with general mathematics model. Relying on the traditional PID regulation technology is hard to take effective. This paper gives a kind of cokeries gas collector pressure control scheme based on fuzzy control theory. With the use of fuzzy control system, we are not only obtaining improved steady pressure, but also alleviating the pollution level in certain scope.
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4,381
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Please write an abstract with title: Co-Simulation Platform for Simulating Heavy Mobile Machinery With Hydraulic Actuators and Various Hybrid Electric Powertrains, and key words: Machinery, Mechanical power transmission, Hydraulic systems, Load modeling, Hydraulic actuators, Vehicle dynamics, Integrated circuit modeling, Hybrid electric vehicles. Abstract: Computer simulations are important tools for evaluating hybrid electric powertrain concepts. In heavy mobile machinery, the powertrain undergoes traction and often hydraulic loads. The dynamic loads on hydraulic actuators of heavy mobile machinery can be studied using detailed physics-based simulation models. The effect of coupling hydraulic actuators to various configurations of hybrid electric powertrains is studied using a co-simulation approach in this study. The case example of a tractor modeled using multibody dynamic approach combined with four powertrain configurations with different topology and hydraulic actuator coupling is investigated. A farm tractor was simulated in a virtual environment with deformable terrain in a soil digging and dumping work cycle. The coupling of hydraulics to the electric energy source in a series-parallel topology achieved fuel savings of 10.5% and total energy savings of 12.3%. The presented modeling method can be used to simulate various heavy mobile machinery to evaluate hybrid electric powertrains using work cycles created by human operators.
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4,382
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Please write an abstract with title: Understanding Barriers to Internal Startups in Large Organizations: Evidence from a Globally Distributed Company, and key words: Technological innovation, Decision making, Distributed databases, Companies, Market research, Software, Planning. Abstract: Large global companies need to speed up their innovation activities to increase competitive advantage. However, such companies' organizational structures impede their ability to capture trends they are well aware of due to bureaucracy, slow decision-making, distributed departments, and distributed processes. One way to strengthen the innovation capability is through fostering internal startups. We report findings from an embedded multiple-case study of five internal startups in a globally distributed company to identify barriers for software product innovation: late involvement of software developers, executive sponsor is missing or not clarified, yearly budgeting and planning, unclear decision-making authority, lack of digital infrastructure for experimentation and access to data from external actors. Drawing on the framework of continuous software engineering proposed by Fitzgerald and Stol, we discuss the role of BizDev in software product innovation. We suggest that lack of continuity, rather than the lack of speed, is an ultimate challenge for internal startups in large global companies.
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4,383
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Please write an abstract with title: Dual-Polarization Multi-Layer Antenna by Patch Asymmetry with Simple Integrated Feeding for In-Band Full-Duplex Systems, and key words: Slot antennas, Communication systems, Layout, Europe, Couplers, Aperture coupled antennas, Bandwidth. Abstract: A new two-port dual-polarized antenna for In-Band Full-Duplex (IBFD) applications is proposed. The antenna consists of two H-shaped slots, asymmetrical stacked aperture coupled patches to improve bandwidth, and a simple Rat-Race hybrid coupler feeding system integrated within the antenna system. In this configuration, antenna port one can provide a differential phase shift of 180° between two H-shaped slots to excite linear polarization, while port two can generate an orthogonal linearly polarized mode. Using such a feeding scheme and patch asymmetry, only one hybrid coupler is required for dual-polarization. The antenna is well matched from about 2.3 to 2.4 GHz while isolation levels are above 35 dB. Maximum realized gains are 7.1 dBi and 8.2 dBi for port one and two, respectively. Using such a simple feeding approach and asymmetrical antenna layout, there are no requirements for connecting cables or additional external couplers which significantly simplifies the antenna system.
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4,384
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Please write an abstract with title: A Data-Characteristic-Aware Latent Factor Model for Web Services QoS Prediction, and key words: Quality of service, Predictive models, Web services, Clustering algorithms, Data models, Sparse matrices, Reliability. Abstract: How to accurately predict unknown quality-of-service (QoS) data based on observed ones is a hot yet thorny issue in Web service-related applications. Recently, a latent factor (LF) model has shown its efficiency in addressing this issue owing to its high accuracy and scalability. An LF model can be improved by identifying user and service neighborhoods based on user and service geographical information. However, such information can be difficult to acquire in most applications with the considerations of information security, identity privacy, and commercial interests in a real system. Besides, the existing LF model-based QoS predictors mostly ignore the reliability of given QoS data where noises commonly exist to cause accuracy loss. To address the above issues, this paper proposes a data-characteristic-aware latent factor (DCALF) model to implement highly accurate QoS predictions, where ‘data-characteristic-aware’ indicates that it can appropriately implement QoS prediction according to the characteristics of given QoS data. Its main idea is two-fold: a) it detects the neighborhoods and noises of users and services based on the dense LFs extracted from the original sparse QoS data, b) it incorporates a density peaks-based clustering method into its modeling process for achieving the simultaneous detections of both neighborhoods and noises of QoS data. With such designs, it precisely represents the given QoS data in spite of their sparsity, thereby achieving highly accurate predictions for unknown ones. Experimental results on two QoS datasets generated by real-world Web services demonstrate that the proposed DCALF model outperforms state-of-the-art QoS predictors, making it highly competitive in addressing the issue of Web service selection and recommendation.
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4,385
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Please write an abstract with title: Energy Consumption Minimization in Cognitive Radio Mobile Ad-Hoc Networks using Enriched Ad-hoc On-demand Distance Vector Protocol, and key words: Computers, Energy consumption, Computational modeling, Routing, Minimization, Routing protocols, Ad hoc networks. Abstract: Ad-hoc networks with poor routing affects the complete network and it leads to enhanced delay in delivering the packets to destination and consumption of energy in an exhaustive manner. Significant task of CR-MANET is to find a better route which consumes less delay and energy. This paper proposes an enriched version of ad-hoc on-demand distance vector (EAODV) routing protocol to meet the challenges faced in CR-MANET. EAODV involves four different phases which are route request method, updating the routing table, route request on demand and route lifetime. These four phases help EAODV to avoid congestion and discover better route to destination. EAODV is intended to locate the best alternative route in a short period of time amid route failure by dynamically selecting the optimal route. Before sending the packets, EAODV evaluates the selected routes using the residual energy of nodes in the path. If it is not satisfied, then next best route is selected. Efficiency of EAODV is demonstrated by a comprehensive simulation and it got resulted in better outcomes in terms of minimizing delay and energy consumption.
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4,386
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Please write an abstract with title: Incorporating Constraints in Reinforcement Learning Assisted Energy System Decision Making: A Selected Review, and key words: Training, Operations research, Costs, Decision making, Asia, Reinforcement learning, Safety. Abstract: With the widespread use of reinforcement learning (RL) in the energy system, the damage to the system caused by the agents' stochastic exploration is beginning to be appreciated. We need to ensure the safety of agents during the whole training process, even at each time step. Therefore, we need to consider how to incorporate safety constraints into RL. In this paper, we summarize two approaches to soft constraints and three approaches to hard constraints, respectively, and provide a comparative analysis of their advantages and disadvantages. Finally, we conclude approaches to how to incorporate constraints in RL, and give an outlook on future research directions.
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4,387
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Please write an abstract with title: Using open source software in product development: a primer, and key words: Open source software, Product development, Law, Costs, Licenses, Embedded software, Computer industry, Legal factors, Protection, Linux. Abstract: There are important legal aspects involved in using open source software in commercial products. Here are answers to common questions on how to handle these issues to mitigate risk. The use of open source software in industrial products is growing rapidly because its many advantages are well known. However although we in industry understand liability and intellectual-property-right risks fairly well, the implication of OSS-related legal and managerial issues are new to many of us. Legal aspects can vary greatly from one piece of OSS to another depending on the license scheme used. We discuss the major legal aspects and risks in using OSS and how to mitigate them in product development. We've ordered the information in a top-down approach, starting with a definition of OSS, its benefits, and then some risks and experiences with managing it in software engineering practice.
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4,388
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Please write an abstract with title: Design and Implementation of Visually Impaired Assistant system, and key words: Image color analysis, Face recognition, Clothing, Computer architecture, Speech recognition, Ubiquitous computing, Mobile applications. Abstract: The need for independent living is recognised in the case of visually impaired people who face a variety of issues, including social isolation.They are forced to live in strange environments with no means of assistance. Today’s tech world should supply them with this assistance for easier socialization. Our aim is to facilitate the life of visually impaired people who could lack the technology to help them in their lives. This project is proposed to focus on the development of a mobile application that uses voice commands and text to voice technology to enable users to interact with the mobile application. The user captures the item they want to identify using the smartphone’s camera and pick the image they want to upload for processing. The image chosen then will undergo through pre-processing techniques depending on the feature the user chose, the features include Money recognition CNN MobileNet architecture was used to analyze the Egyptian banknotes and Color and patterns recognition CNN resnet50 architecture was used to analyze the color and pattern of the clothing. As well, the application allows the user to register or login using facial recognition to further facilitate the experience for users. The application is designed to be effective and can be easily navigated by visually impaired users. ResNet50 architecture produce the highest accuracy in patterns and colors cloth recognition, Mobilenet architecture produce the highest accuracy in currency recognition.
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4,389
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Please write an abstract with title: Dealing With Challenges Developing a Gateway to the “End of the World”—The Brazilian Antarctic Station Case Study, and key words: Antarctica, Monitoring, Biomedical monitoring, Temperature sensors, Maintenance engineering, Logic gates, Temperature measurement. Abstract: The circadian rhythm is the period of about 24 h, which is the basis of the human biological cycle. It coordinates human daytime activities and body rest, and influences cognitive learning and processing information in the brain during sleep. Light rhythmically influences these hormonal physiological procedures. External factors such as the exposure to artificial light can also interfere with the circadian rhythm, causing sleep and wake disturbances. Remote monitoring systems can be used to better understand how the artificial light influences sleep and bodily rhythms, integrating light and physiological measurements to assess their interaction points. We developed an equipment to monitor the environmental light spectrum and gather data from wrist devices, collecting data on sleep quality and daytime activities. This study shows the challenges faced during the development of this monitoring equipment and the lessons learned from its construction and installation at the Brazilian Antarctic research station.
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4,390
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Please write an abstract with title: A Dual-State Filter for a Relative Velocity Aiding Strapdown Inertial Navigation System, and key words: Mathematical model, Filtering algorithms, Navigation, Damping, Oceans, Information filters. Abstract: The strapdown inertial navigation system that uses the aiding velocities from a relative log is usually affected by the ocean current. Therefore, a dual-state filter algorithm to alleviate the effect from unknown ocean current is proposed in this article. Generally speaking, the ocean-current velocity is relatively stable, in other words, two adjacent samples over a short period can be considered to be unchanged. Consequently, our algorithm chooses the difference between the two adjacent sample points from the log as the external measurement information of the integrated navigation system, where the effect from ocean-current velocity will be alleviated in the filter. Nevertheless, the previous state (the previous velocity error) will exist in the filter updating process. The common Kalman filter algorithm cannot cope with this condition, so we rederived filter equations regarding the dual-state filter based on the previous state and the current state. The final results of simulation and experiment demonstrate that the dual-state filter algorithm can alleviate the effect from unknown ocean current.
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4,391
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Please write an abstract with title: Cloud and WebRTC based Laboratory Solution for Practical Work in Computer Science for a Traditional University, and key words: Cloud computing, Adaptation models, Computational modeling, Scalability, Vocational training, Virtual machining, Monitoring. Abstract: This paper first presents the difficulties for a classical university in Africa in general and in Senegal in particular, to carry out practical work in class, i.e. from a local laboratory or a physical location. These difficulties are linked to several economic, material and human factors. Thus, this paper first proposes to study a model of laboratories for online practical work applicable in several areas of STEM (science, technology, engineering and mathematics). Then, for the practical implementation of the laboratory, the authors are interested in practical computer science work for development and network environments. The objective of this paper is therefore to implement a virtual laboratory that will allow students to create remote work in IT using the cloud to improve the performance, availability and scalability of existing practical work. The type of laboratory proposed is essentially based on virtual machines accessible via a web platform created and connected with the cloud that contains these virtual machines. It is also dynamic and flexible, i.e. the teacher, from this platform, first makes a request to the cloud administrator to create machines for a specific type of practical work for a group of students. Then, the teacher places in the platform the instructions of the practical work visible to the students. At this stage, the students will connect to the platform for the realization of the practical work with virtual machines following the instructions given by the teacher. The teacher’s monitoring and supervision of the practical work in synchronous or asynchronous mode is also ensured. The integration of WebRTC technology allows instant discussion between the learner and the teacher during practical work.
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4,392
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Please write an abstract with title: Monolithic integration of a semiconductor optical amplifier (SOA) and a high-speed waveguide p-i-n photodiode using asymmetric twin-waveguide technology, and key words: Semiconductor optical amplifiers, Optical waveguides, Monolithic integrated circuits, Semiconductor waveguides, PIN photodiodes, High speed optical techniques, Integrated optics, Stimulated emission, Optical materials, Semiconductor materials. Abstract: An optical mode transformer, semiconductor optical amplifier, and waveguide photodiode are monolithically integrated without regrowth using separately optimized materials based on asymmetric twin-waveguide technology. The device shows a peak responsivity of 11 A/W and a 3 dB electrical bandwidth of 36 GHz.
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4,393
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Please write an abstract with title: An Enhanced Dynamic Image Watermarking Framework based on Phase Congruency and Saliency, and key words: Image coding, Heuristic algorithms, Signal processing algorithms, Watermarking, Resists, Visual systems, Prediction algorithms. Abstract: Perceptual watermarking approaches achieve better image fidelity with the advantages of the Human Visual System (HVS). Saliency uses the advantages of this feature by identifying different visually perceptual regions of an image. Additionally, Phase congruency (PC) exploits those features of digital images by detecting the corner points. In the proposed method, the information hiding Capacity is generated from both bit depth maps created by comparing phase congruency results and saliency outcomes of an image that ascertains the low perceptually visible pixels (utilizing the Least Significant Bit (LSB) technique). The key idea is to ensure an additional layer of security using Symmetric Key Cryptography (SKC) and to hide information in a less observant area that is not easily perceptible inside the cover image. The experimental result analysis ensures better imperceptibility and robustness as it resists different attacks along with superior data hiding capacity.
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4,394
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Please write an abstract with title: Reliability of physical system, and key words: Reliability theory, Electronic equipment, Reliability engineering, Graph theory, Constraint optimization, Constraint theory, Weapons, Probabilistic logic, Signal analysis, Flow graphs. Abstract: This paper presents the general concept of the reliability of the complex physical system which consists of a number of unreliable elements. Such a system is analyzed systematically by means of algebraic and topological theory. Various properties concerning the system reliability are established. The methods of linear graph theory are used to find the theoretical relationship between element reliability and system complexity. The optimizing the reliability of a basic system under certain constraints can be accomplished by the application of the theory described. A numerical procedure for finding the optimum solution is developed to facilitate computation.
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4,395
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Please write an abstract with title: Non-Orthogonal Multiple Access in the Presence of Additive Generalized Gaussian Noise, and key words: NOMA, Silicon carbide, Multiplexing, Interference, Gaussian noise, Additives, Pairwise error probability. Abstract: In this letter, we investigate the performance of non-orthogonal multiple access (NOMA), under the assumption of generalized Gaussian noise (GGN), over Rayleigh fading channels. Specifically, we consider a NOMA system with L users, each of which is equipped with a single antenna, and derive an exact expression for the pairwise error probability (PEP). The derived PEP expression is subsequently utilized to derive a union bound on the bit error rate (BER) and to quantify the diversity orders realized by NOMA users in the presence of additive white (AW) GGN. Capitalizing on the derived PEP expression and the union bound, the error rate performance of NOMA users is further evaluated for different special cases of AWGGN. The derived analytical results, corroborated by simulation results, show that the shaping parameter of the GGN (α) has negligible effect on the diversity gains of NOMA users, particularly for large α values. Accordingly, as in the case of additive white Gaussian noise (AWGN), the maximum achievable diversity order is determined by the user's order.
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4,396
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Please write an abstract with title: Dealing with Robustness of Convolutional Neural Networks for Image Classification, and key words: Robustness, Indexes, Cancer, Testing, Biomedical imaging, Convolutional neural networks, Task analysis. Abstract: SW-based systems depend more and more on AI also for critical tasks. For instance, the use of machine learning, especially for image recognition, is increasing ever more. As state-of-the-art, Convolutional Neural Networks (CNNs) are the most adopted techniques for image classification. Although they are proved to have optimal results, it is not clear what happens when unforeseen modifications during the image acquisition and elaboration occur. Thus, it is very important to assess the robustness of a CNN, especially when it is used in a safety critical system, as, e.g., in the medical domain or in automated driving systems. Most of the analyses made about the robustness of CNNs are focused on adversarial examples which are created by exploiting the CNN internal structure; however, these are not the only problems we can encounter with CNNs and, moreover, they may be unlikely in some fields. This is why, in this paper, we focus on the robustness analysis when plausible alterations caused by an error during the acquisition of the input images occur. We give a novel definition of robustness w.r.t. possible input alterations for a CNN and we propose a framework to compute it. Moreover, we analyse four methods (data augmentation, limited data augmentation, network parallelization, and limited network parallelization) which can be used to improve the robustness of a CNN for image classification. Analyses are conducted over a dataset of histologic images.
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4,397
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Please write an abstract with title: Doorway to the United States: An Exploration of Customs and Border Protection Data, and key words: big data, passenger-centric, wait time prediction. Abstract: This paper presents a data-driven study of wait time patterns for international arriving passengers across all sixty-one terminals from the forty-four airports of entry of the United States. Each airport is an independent entity which operates with various airlines and handles demand volumes differently. This induces seasonal variation in service quality from one airport to another. Exploring six years worth of data, this paper investigates the current and long-term performance trends - an increasing number of flights versus a decreasing number of customs booths - of all airports of entry from a passenger perspective. A performance analysis is then conducted that compares average wait times of incoming passengers, considering incoming traffic ratios and allocated resources. Leveraging machine learning algorithms, six regression algorithms are trained and tested to accurately predict passenger wait times through customs at selected airports. An analysis of the performance of these models shows that the best approach - using a Gradient Boosting regressor for each terminal of entry - can capture the daily and seasonal variations of traffic patterns and immigration booth availabilities with a mean absolute error of less or equal to 5 minutes for twenty-eight terminals of entry and less than 10 minutes for all terminals. Observations show significant disparities across airports that may be explained by the foreign/US passenger ratio and the quality of booth management.
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4,398
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Please write an abstract with title: A framework for image based authentication, and key words: Authentication, Protocols, Security, Displays, Image coding, Scalability, IEC standards, ISO standards, Image recognition, Humans. Abstract: This paper presents an innovative framework for user authentication based on images. Common user authentication based on passwords has the main drawback of the human difficulty in recalling them. Images are instead easier to remember than passwords. Moreover, modern compression and transmission techniques make image exchange between different devices (e.g. mobile phones, personal digital assistants, laptops, and workstations) in heterogeneous networks practically feasible. In the proposed approach, images are coded using the emerging JPEG2000 standard and taking advantage of many of its features (e.g. image scalability, embedded bitstream, image tiling, and interactivity protocol). The described image based authentication is more secure than the common approach based on passwords.
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4,399
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Please write an abstract with title: New determination of the liquidus line of AuCo by magnetic measurements, and key words: Magnetic liquids, Magnetic variables measurement, Temperature, Magnetization, Tellurium, Cobalt alloys, Magnetic field measurement, Annealing, Solids, Magnetic properties. Abstract: Magnetic measurements of Au-Co alloys at high temperatures are presented. They prove that Au73Co27 is not the eutectic alloy but a hypereutectic one; the phase diagram is corrected and the eutectic composition is determined: 24.2 ± .2 at. % Co. Magnetic measurements of the eutectic alloy indicate the existence of small Co-clusters in the liquid state only a few degrees above the eutectic temperature.
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