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8,300 | Please write an abstract with title: Two-dimensional monolithic lead chalcogenide infrared sensor arrays on silicon read-out chips and noise mechanisms, and key words: Lead compounds, Epitaxial growth, CMOS integrated circuits, Integrated circuit noise. Abstract: A two-dimensional narrow-gap infrared (IR) focal plane array on an Si substrate where the Si substrate contains the active addressing electronics is described. The array consists of 96 /spl times/ 128 pixels with 75-/spl mu/m pitch and is fabricated in a lead-chalcogenide layer grown epitaxially on the Si read-out chip. The cut-off wavelength is 5.5 /spl mu/m. Each pixel contains a bare Si area, onto which epitaxial growth occurs, and an access transistor. The Si-chips are fabricated in CMOS technology with standard Al-metallization, and the lead chalcogenide layer (PbTe) is grown by molecular beam epitaxy onto the completely processed and tested chips. The photovoltaic IR sensors exhibit mean differential resistances at zero bias Ro of 4 M/spl Omega/ at 95 K, and yield is up to 98%. The sensitivities described by Ro are limited by the density of threading dislocations crossing the active areas of the devices, as each such dislocation causes a shunt resistance on the order of magnitude of 1 G/spl Omega/. |
8,301 | Please write an abstract with title: The Sound Change of in 足 Zhengzhou Dialect, and key words: phonological status, dialectal pronunciations, sound change, language contact. Abstract: Through the inspections of historical phonological statuses and dialectal pronunciations of 足, and from the perspectives of sound change, language contact and lexical diffusion, this paper explains why the various pronunciations of 足 coexist in Zhengzhou dialect at present, and makes a prediction of the future evolutionary trend about these different pronunciations. Meanwhile, this paper points out that both internal rules of sound change(endogenous) and external influences of language contact(exogenous) should be paid attention when studying sound change diachronically or synchronically. |
8,302 | Please write an abstract with title: Density modulation of the thin slab beam over a metal grating, and key words: Optical modulation, Slabs, Gratings, Optical surface waves, Surface waves, Couplers, Connectors, Power engineering and energy, Atom optics, Power generation. Abstract: Summary form only given, as follows. Summary form only given. We present the density modulation of a relativistic slab beam by a traveling surface wave propagating along the beam over a metal grating. A dispersion relation of the surface wave is derived from boundary conditions on two interfaces, the slab beam and the metal grating. The interaction between the thin slab beam and the surface wave is described in a cold beam limit. A self-modulation of the beam density is amplified with propagation due to a feedback offered by the grating. The analysis is expanded to a warm beam with a relative velocity spread. |
8,303 | Please write an abstract with title: Compact fiber optic ultrasound transducer with integrated ultrasound emission and detection, and key words: Optical fibers, Electric potential, Ultrasonic imaging, Transducers, Bandwidth, Lasers and electrooptics, Laser applications. Abstract: A compact fiber optic ultrasound transducer with integrated ultrasound emission and detection is developed. The transducer exhibits an emission pressure of 0.45MPa and a noise equivalent pressure of 72.8Pa. |
8,304 | Please write an abstract with title: HandKey: Knocking-Triggered Robust Vibration Signature for Keyless Unlocking, and key words: Vibrations, Oscillators, Behavioral sciences, Accelerometers, Security, Costs, Mobile computing. Abstract: Door lock is regarded as a critical line of defending the privacy and security of personal areas. However, for inner doors in environments like factories, existing locking mechanisms can be poor in user-friendliness and high in cost. For instance, mechanical locks require carrying keys that inevitably compromise user experiences, while smart locks always require non-trivial sensors. Therefore, inner doors urgently require a lightweight unlocking scheme that can properly balance user-friendliness, cost, and security. To this end, we propose HandKey as a keyless unlocking scheme to supplement existing lock systems. HandKey relies on two principles: the simplicity of hand knocking doors and the uniqueness of vibration triggered by the knocking force. In other words, a door and a hand knocking it jointly form a unique physical system that generates hand-dependent and user-specific vibration signatures uniquely representing a user identity. In designing HandKey, we first analyze the vibration mechanism behind it and the impacts of gestures and door materials on vibration signatures. Then we innovatively construct a signal processing and deep learning-based pipeline to extract signatures robust to variable knocking behaviors for representing user identity. Finally, we implement a HandKey prototype and use extensive evaluation to demonstrate its security and effectiveness. |
8,305 | Please write an abstract with title: A Novel Concept Methodology of In-direct Cold Plate Liquid Cooling Design for Data Center in CPU Socket Area, and key words: Cold plates, Liquid cooling, Performance analysis, Thermal resistance, Data centers. Abstract: With the development of 5G, AI, IoT and smart city technologies, data center is the core cornerstone of Computing, Storage and Interconnection. With the computing capability increasing, the CPU power dissipation is dramatically increased in recent years. The Intel Xeon CPU is targeting up to 300W or even higher power level in the Intel latest silicon road map, which brings big thermal challenge to design feasible thermal solutions for both system and data center. The in-direct cold plate liquid cooling solution is proposed with high cooling efficiency, better PUE and improved noise control in data center. This paper discusses the different cold plate design including the flow channel design, flow impedance and thermal resistance comparison. A new liquid cooling for CPU cold plate product concept and performance assessment methodology as well as engineering practice from JD.com system design is also proposed. |
8,306 | Please write an abstract with title: Dielectric Characterization of Curved Structures Using Flangeless Open-Ended Waveguide Measurement, and key words: Surface waves, Electromagnetic waveguides, Flanges, Electromagnetic modeling, Size measurement, Dielectric measurement, Dielectrics. Abstract: Open-ended waveguide measurement of layered structures is a well-developed method for determining dielectric and thickness properties of the layers. A full-wave electromagnetic model has been previously developed, which includes the effects of the high-order modes, as a forward model describing the complex reflection properties of layered structures. The open-ended waveguide flange design has also been optimized to closely approximate the electromagnetic assumptions made in the electromagnetic model. However, in certain measurement situations the size of the flange creates gaps between the aperture of the waveguide and the structure being tested. This is often the case for uneven or curved surfaces, which affects the accuracy of dielectric property measurements. This paper presents an empirical method to account for the effect of a flangeless open-ended waveguide probe to enable measurement of curved surfaces and significantly reduce the undesired effect caused by such gaps. |
8,307 | Please write an abstract with title: Direct frequency comb generation from an octave spanning prismless Ti:sapphire laser, and key words: Frequency, Mirrors, Laser noise, Optical noise, Ultrafast optics, Pump lasers, Fiber lasers, Delay, Laser theory, Optical harmonic generation. Abstract: An octave spanning prismless Ti:sapphire laser is demonstrated. The octave is reached at 20 dB below the average power level. A highly stable carrier-envelope beat note with 30 dB signal to noise in a 100 kHz detection bandwidth is observed. |
8,308 | Please write an abstract with title: Simultaneous Competition Modeling of Generations and Consumers in the New Market Structure based on the Supply Function Equilibrium Model Systems, and key words: Costs, Profitability, Conferences, Network security, Generators, Proposals, Power generation. Abstract: Today, incentive policies have been proposed to contribute to small consumers in the market to improve network security. In this paper, the simultaneous competition of small consumers in the form of independent firms and power plants in the new market structure is modeled and the impact of competition of these firms on the behavior of generation firms and network costs is investigated. Given the multiplicity of consumer presence in this market and the rumor that this may slow down the market settlement process, the effect of imposing restrictions on a strategy change for all participants has been investigated. |
8,309 | Please write an abstract with title: Some multiobjective optimizers are better than others, and key words: Computer science, Measurement, Filters, Qualifications, Algorithm design and analysis, Particle swarm optimization, Simulated annealing, Modems. Abstract: The No-Free-Lunch (NFL) theorems hold for general multiobjective fitness spaces, in the sense that, over a space of problems which is closed under permutation, any two algorithms will produce the same set of multiobjective samples. However, there are salient ways in which NFL does not generally hold in multiobjective optimization. Previously we have shown that a 'free lunch' can arise when comparative metrics (rather than absolute metrics) are used for performance measurement. Here we show that NFL does not generally apply in multiobjective optimization when absolute performance metrics are used. This is because multiobjective optimizers usually combine a generator with an archiver. The generator corresponds to the 'algorithm' in the NFL sense, but the archiver filters the sample generated by the algorithm in a way that undermines the NFL assumptions. Essentially, if two multiobjective approaches have different archivers, their average performance may differ. We prove this, and hence show that we can say, without qualification, that some multiobjective approaches are better than others. |
8,310 | Please write an abstract with title: On the Design and Optimization of the Shielded-Pair Transmission Line, and key words: Design optimization, Transmission lines, Transmission line theory, Conductors, Capacitance, Attenuation, Surface resistance, Proximity effect, Electric resistance, Surface impedance. Abstract: The electrical parameters of the shielded-pair transmission Iine are computed using a truncated harmonic expansion for the surface charge density on the conductors. The formulation includes the proximity effect due to the close spacing of the conductors. Parametric curves are given for the capacitance, resistance, and attenuation per-unit length, and the characteristic impedence of the Iine. Both the balanced and the longitudinal modes of propagation are considered and the dimensions for a line with minimum attenuation are determined for each mode. Capacitances measured on model transmission lines are shown to be in good agreement with the theory. |
8,311 | Please write an abstract with title: Study on Mechanism of a Novel Autotransformer for 18-pluse Rectifier, and key words: multi-pulse rectifier, autotransformer, harmonic distortion rate, equivalent capacity. Abstract: From the aspect of the isolated transformer for 18-pulse rectifier, a new topology of the 18-pluse autotransformer-rectifier with the advantages of small equivalent capacity, low harmonics and outstanding symmetrical structure is proposed, which is superior to the existing American patents. The relationship between the input and output currents, the distortion of input current, the relationship between the voltage of each branches and the phase shift angle and the equivalent capacity of the autotransformer are derived by using the potential vector diagram and the balance principle of the magnet potential. The phase shift angle of the proposed novel 18-pulse autotransformer is 20° that is exactly the same with the isolated transformer, which verifies the potential vector of the two is coincident. The input current distortion rate of this autotransformer is 10.05%, which reduces the harmonics of the rectifier to the power grid. The equivalent capacity is only 17.76% of the output power, which greatly reduces the volume and weight of the system. Finally, a prototype is made, which validates the correctness of the theoretical deduction and simulation, and provides a theoretical guide for future design. |
8,312 | Please write an abstract with title: Blind adaptive equalization of underwater acoustic channels using second-order statistics, and key words: Blind equalizers, Adaptive equalizers, Underwater acoustics, Statistics, Timing, Frequency, Spinning, Phase locked loops, Testing, Sea measurements. Abstract: In this paper, a completely unsupervised receiver concept based on nondata-aided timing recovery, blind multichannel equalization and carrier phase recovery is proposed. The core of the receiver is an adaptive multichannel equalizer, which uses linear predictions of the observations. To employ this powerful second-order cyclostationary method, which has been proposed only recently, the influence of a carrier frequency offset, e. g. due to Doppler, is discussed. It is shown that such an offset results in a spinning estimate of the transmitted symbol sequence at the output of the equalizer. To compensate for this rotation, a decision-directed phase-locked loop is proposed. The receiver is then tested with measured shallow water data gathered during the ROBLINKS 1999 sea trial. The obtained results demonstrate that completely blind processing of the received signals is possible. |
8,313 | Please write an abstract with title: High frequency power LDMOS technologies for base station applications status, potential, and benchmarking, and key words: Base stations, Radio frequency, Multiaccess communication, Linearity, Capacitance, Peak to average power ratio, Thermal resistance, Costs, Packaging, Flanges. Abstract: LDMOS technologies based in G. Ma et al. (1996) and H. Brech et al. (2003) have been in dominate position in wireless base station applications for frequencies ranging from 450MHz to 2.7GHz for the last 10 years due to performance, cost, reliability, and power capability advantages. This paper reviews the leading edge LDMOS development at Infineon and discusses future potential and limitation for LDMOS technologies in general; benchmarking with alternative technologies is also presented |
8,314 | Please write an abstract with title: Fully integrated bandpass filters for wireless transceivers-problems and promises, and key words: Band pass filters, Active filters, Filtering, System-on-a-chip, Frequency, Bluetooth, Energy consumption, Dynamic range, Radio transceivers, Noise figure. Abstract: Despite decades of research into developing true, single-chip radio transceivers, most commercial designs continue to rely on off-chip components for bandpass filtering. Implementing these filters on-chip remains nearly as challenging today as it was 10 years ago, due to the demanding system requirements of modern radio standards, and few technologies have made it into commercial production. Exceptions include the sporadic adoption of low-Q active filters in IF subsystems and the occasional use of low-Q LC filtering in front-end designs. This paper overviews filter performance requirements and implementation alternatives, and identifies fundamental as well as technological constraints limiting their use. An example design of a Q-enhanced LC filter for Bluetooth applications at 2.4 GHz is also discussed. |
8,315 | Please write an abstract with title: Performance analysis of distributed acoustic sensing systems based on Rayleigh-backscattering and wFBG-reflecting, and key words: Phase noise, Rayleigh channels, Reflectometry, Acoustic measurements, Acoustics, Real-time systems, Time-domain analysis. Abstract: A low-noise, low-calculation, long-range distributed acoustic sensing (DAS) system based on phase-sensitive optical time-domain reflectometry (Φ-OTDR) is proposed and analyzed. Based on this system, measurements were performed by using both Rayleigh backscattering light and wFBG-reflected light. An average phase noise of -47 dB can be achieved with wFBGs, which is about 15 dB lower than that with Rayleigh backscattering. The experimental results illustrate the potential for wFBGs in the proposed DAS system, which can demodulate external disturbance signal with good linearity and wide frequency response range, and immune to interference fading and polarization fading. |
8,316 | Please write an abstract with title: Simulations of leakage currents found during dry-band arcing on Fiber-optic cables, and key words: Optical fiber cables, Power cables, Pollution, Poles and towers, Leakage currents, Conductors, Mathematical model. Abstract: Fibre optic cables installed in the vicinity of high voltage conductors in the field are exposed to varying environmental conditions. Under certain polluted and wet conditions, leakage currents may flow and under sufficiently severe conditions, dry-band arcing may occur on the surface of the fibre optic cable. The objective of this paper is to present two simulation processes that may be used to predict these leakage currents. These predictions are compared with experimentally determined values for a simplified single phase geometry. The effects of factors such as system voltage, attachment point of the cable on the support structures and span length have been investigated. |
8,317 | Please write an abstract with title: Characterizing and Modelling Non-Linear Rectifiers for RF Energy Harvesting, and key words: Analytical models, Uncertainty, Rectifiers, Harmonic analysis, Impedance, Energy harvesting, Load modeling. Abstract: Radio Frequency Energy Harvesting and power transfer, using rectifying antennas, are increasingly seen as an enabling technology of power-autonomous devices. The non-linearity of the rectification element, the diode, adds challenges when experimentally characterizing and comparing the performance of different rectifiers, requiring complex measurement techniques to characterize a diode experimentally, and adds to the challenges of designing a matching network. This paper presents a method for characterizing the power conversion of a mismatched rectifier using a single-port vector network analyzer, omitting the need for impedance tuners and accurately reflecting the non-linearity of the diode. The proposed approach minimizes uncertainty sources in the test setup and shows close agreement with optimized harmonic balance simulation. Finally, harmonic balance simulation is utilized to compare the source and load impedance of the two most common rectifier topologies, a single series and a voltage doubler, acting as a guide for matching network and antenna design. |
8,318 | Please write an abstract with title: Array Gain Prediction of Horizontal Line Array Using Monitoring Sea Surface Fluctuations, and key words: Sea surface, Fluctuations, Correlation, Acoustic scattering, Acoustic arrays, Propagation losses, Attenuation. Abstract: As an important parameter for evaluating sonar detection performance, array gain depends on the spatial-temporal correlations of the acoustic field. Acoustic scattering from the sea bottom and surface fluctuations has a significant influence on sound propagation under the circumstances of rough boundaries and high frequencies. Based on the normal-mode perturbation theory in shallow water with rough boundaries, this paper studies the effects of surface fluctuations on the transmission loss, horizontal correlations of the acoustic field, and conventional beamforming array gain of a horizontal line array. The simulation results show that the attenuation coefficients of higher-order modes are larger than that of lower-order modes due to the acoustic scattering caused by surface fluctuations. In other words, the rough surface makes the higher-order modes attenuate greatly, resulting in the interference fluctuations of transmission loss concerning the distance being weakened to a certain degree. Therefore, the horizontal spatial correlation fading of the acoustic field is slowed down, making the array gain of the horizontal line array with rough boundaries slightly higher than that with flat boundaries. |
8,319 | Please write an abstract with title: ProgArch: Modeling the Adoption of Enterprise Architecture to Manage Development Program, and key words: Tools, Stakeholders, Monitoring, Computer architecture, Planning, Acceleration, Data models. Abstract: Although various frameworks, methods, and tools have been used in a development program, a comprehensive framework that can integrate all aspects and needs of a complex development program is not available. Simultaneously, in the IT/IS context, Enterprise Architecture (EA) concept has existed and becomes the organization's blueprint for aligning its vision and mission, business processes, and information technology.How to model an architectural framework that can adopt EA's capabilities and advantages and apply it in a complex development program context with significant IT, applications, and data components is key questions that lead this research. In this paper, ArchiMate 3.0, an EA framework from Open Group, was adopted to represent the development program management structure. We use observation from the stunting prevention acceleration program in Indonesia to explore EA's strength in representing the description, analysis, and visualization of multiple aspects of a complex case. It shows that the model we built can adopt important EA framework features like artifact integration, searchability, traceability, and multi-dimensional view capability. |
8,320 | Please write an abstract with title: Research on Risk Prevention and Claim Application of Construction Contract Management in Construction Engineering, and key words: Systematics, Contract management, Standardization, Regulation, Personnel, Software engineering. Abstract: Through studying and analyzing the current situation of risk prevention and claim in construction contract management, many problems in contract management were found, and the related theoretical knowledge of risk prevention and claim was deeply studied, and then the construction contract management was studied to find out the components of contract management and the related methods of contract management. At last, the paper studies the classification basis of construction contract prevention and claim, the management of construction contract, and analyzes three types of actual engineering claim cases. It is concluded that the preparation for risk prevention should be strengthened in the construction contract, the relevant laws and regulations should be followed in the process of formulating the contract, and the contract management should be conscientious and responsible. It find and solve problems in time, and it seems to assign project responsibilities to specific personnel. By analyzing and studying the cases of risk prevention and claim in the construction contract management of related construction projects, and combining the related knowledge of risk prevention and the related treatment methods of claim, this paper puts forward some related methods to solve the problems existing in the current construction contract management of construction projects. |
8,321 | Please write an abstract with title: Autofocus Measurement for Electronic Components Using Deep Regression, and key words: Lenses, Estimation, Deep learning, Training, Task analysis, Manufacturing, Computational modeling. Abstract: Image-based focus measurement in the manufacturing process is important for tasks such as automated inspection, automated assembly, and autosoldering. To inspect or manipulate an object, the visual system must sense the best image position to ensure that all the details of the product can be viewed. For this reason, an autofocus system is required. Traditional autofocus systems based on depth-from-focus (DFF) or depth-from-defocus (DFD) rely on a series of images by moving the lens with a control motor to find the sharpest location. The processing time defers it for in-line, real-time industrial applications. In this article, we propose a deep neural network regressor for fast and accurate autofocus. The convolutional neural network (CNN) model is proposed and evaluated for the autofocus task on a variety of electronic surfaces, including wafers, liquid crystal display (LCD), and ball grid array (BGA). The proposed deep regression model requires only one single sensed image of the object to estimate the depth. The effect of environmental variations in the illumination is evaluated for the robustness of the proposed method. Experimental results indicate the proposed CNN Regressor can achieve fast and accurate results for the tested objects with repetitive and arbitrary patterns. |
8,322 | Please write an abstract with title: Maser at elevated temperature, and key words: Masers, Temperature measurement. Abstract: Summary form only, as given. A maser operatingin a closed cycle refrigerator (CCR) at 40 degrees K has been developed. The maser head containing a silvered ruby cavity rests directly upon the cold rod of the CCR. The head is isolated from the metal waveguides by means of a vacuum gap and choke flanges. Due to this arrangement, the heat flow towards the head is low (<0.5 watts). |
8,323 | Please write an abstract with title: Application of multiple linear regression statistical model: Executive compensation incentives, risk-taking and R&D investment, and key words: Correlation, Statistical analysis, Linear regression, Companies, Big Data, Data models, Mathematical models. Abstract: This article uses multiple statistical analysis methods to verify the correlation between variables through the connection of multiple linear regression equations. Through the analysis of the panel data of different types of executive compensation incentives and R&D investment in Chinese listed companies, it is found that there is a significant positive correlation between executive compensation incentives and R&D investment. Further research found that executive monetary compensation incentives and on-the-job consumption affect the R&D investment of enterprises by influencing the risk-taking ability of executives. |
8,324 | Please write an abstract with title: Understanding suspension D.C. plasma spraying of nanostructured coatings, and key words: Thermal spraying, Coatings, Testing, Plasma temperature, Spectroscopy, Plasma accelerators, Nanoparticles, Acceleration, Heat transfer, Plasma density. Abstract: Summary form only given. Injecting nanosized particles in a D.C. plasma jet would require, to give them a high enough, momentum, a huge carrier gas flowrate, which would drastically perturb the plasma jet. To overcome this problem a suspension of these particles is mechanically injected with in the plasma jet. The high momentum of the latter tears the liquid jet in tiny droplets (1-3 /spl mu/m) which evaporate in a few microseconds. This scenario has been checked by emission spectroscopy of the plasma jet and simple calculations. The agglomerates of nanoparticles contained in the evaporated droplets are then melted and accelerated before flattening onto the substrate. They result in splats which diameter is between 100 and 2000 nm and which thickness varies between 60 and 300 nm. The way particles flatten and splats form is tested by collecting the latters at different distances downstream of the nozzle exit. The calculations of momentum and heat transfers to agglomerates confirm the experimental results related to the sand-off distance and the required plasma jet enthalpy and velocity. The process has been tested on stabilized zirconia and perovskite coatings sprayed on smooth substrates (Ra <0.05 /spl mu/m) preheated at different temperatures. Coatings can be very dense with less than 1% porosity or highly porous (>20%). To achieve LaMnO3 coatings which are not partially decomposed the particles have been doped with MnO2. With deposition rates of about 15 /spl mu/m/h.m2 and very intricated interface between zirconia and perovskite, the process seems very promising for SOFC's manufacturing. |
8,325 | Please write an abstract with title: The Free Response of an Identified Model of a Linear System with a Completely Unknown Harmonic Disturbance Exactly Forcasts the Free-Plus-Forced Response of the True System Thereby Enabling Adaptive MPC for Harmonic Disturbance Rejection, and key words: Linear systems, Adaptation models, Adaptive systems, Conferences, Predictive models, Harmonic analysis, System identification. Abstract: This paper considers system identification in the presence of an unmeasured, unknown, and unmatched multitone harmonic disturbance with completely unknown spectrum. It is shown that the identified model possesses spurious poles at the disturbance frequencies that are cancelled by coincident, spurious zeros. Although the presence of the spurious poles is expected, this paper shows that the free response of the identified model is identical—in frequencies, amplitudes, and phases—to the free-plus-forced response of the true system. Consequently, by retaining—rather than cancelling—the coincident, spurious poles and zeros, the identified model has the ability to forecast the future response to an unknown harmonic input over a prediction horizon during which the harmonic disturbance persists. A numerical example illustrates the usefulness of this property to model predictive control with concurrent system identification for rejecting unmeasured, unknown, and unmatched harmonic disturbances with completely unknown spectrum. |
8,326 | Please write an abstract with title: Formal models of object-oriented patterns using RTPA, and key words: Object oriented modeling, Software engineering, Computer architecture, Software design, Algebra, Concrete, Application software, Software reusability, Unified modeling language, Drives. Abstract: The development of generically reusable object-oriented components is a task with a higher degree of cognitive complexity. Design patterns are an important means to deal with this difficulty for capturing design notions and recurrent architectures in software engineering. Since patterns are inherently complicated, the conventional diagram-based techniques cannot rigorously and explicitly denote the architectures and behaviors of patterns. Real-time process algebra (RTPA) is used to describe software patterns formally and explicitly in order to enhance the understandability of their architectures, semantics, and behaviors. This paper presents a formal model of generic patterns, which focuses on architectural and associational descriptions of a pattern's interfaces, implementation, and instantiations. A typical creational pattern, the builder pattern, is provided as a case study on the applications of the generic pattern model. This paper demonstrates that software patterns can be rigorously, efficiently, and effectively designed and implemented based on the formal pattern model |
8,327 | Please write an abstract with title: Design and implementation of single-phase three-wire rectifier-inverter for UPS applications, and key words: Uninterruptible power systems, Switches, Circuits, Topology, Zero voltage switching, Voltage control, Rectifiers, Inverters, Safety, Capacitors. Abstract: Single-phase three-wire UPSs are widely applied to commercial applications for supplying the 110 V/220 V critical loads. For the on-line UPS containing the rectifier and inverter circuits with cascaded connection, it is better to connect together the neutral line of both circuits for safety reason. However, in some applications only two-wire input is available such that the neutral line of the three-wire output has to float. This may cause unbalanced DC-link capacitor voltages when two 110 V loads are unbalanced if the split-capacitor topology is employed. Similarly, two 110 V output voltages will be unbalanced in the bypass mode if the input voltage is two-wire. To solve these problems a rectifier-inverter topology with a N-leg switch connecting to the neutral line of the load is proposed in this paper to replace the conventional split-capacitors topology. As the input voltage is three-wire that the input and the load voltages have common neutral line, the control signal of the N-leg switch is zero aiming for only flowing the unbalanced load current. On the contrary, as the input voltage is two-wire the control signal of the N-leg turns to balance two 110 V load voltages. With the proposed configuration not only two 110 V output voltages are balanced, the input power factor is also maintained unity and the input current is balanced even under three-wire input voltage and unbalanced loads. In addition to model the five-legs rectifier-inverter, the detailed design of the controllers is provided. A 4 KVA system is designed and implemented in this paper. |
8,328 | Please write an abstract with title: Research on Modeling of Wind Speed-Power Curve for Wind Farm, and key words: Wind speed, Wind power generation, Wind farms, Fitting, Estimation, Kernel, Data models. Abstract: High-precision wind power prediction is an important method to ensure the safety and stability of wind power integration. The power curve of wind farm plays an important role in the prediction of wind power. In this paper, the data selection of wind speed-power curve modeling and the fitting of wind speed power curve are studied. Firstly, two-dimensional kernel density estimation method is used to eliminate the abnormal data in the wind farm. Then, a method combined Bines with polynomial fitting (Bins-Polynomial) is proposed to estimate the speed-power curve. Finally, the Bins-Polynomial method is compared with the other three methods, and the results show that the accuracy of the Bins- Polynomial method is higher, which can improve the accuracy of wind power prediction. |
8,329 | Please write an abstract with title: Assistive Signals for Deep Neural Network Classifiers, and key words: Deep learning, Computer vision, Three-dimensional displays, Perturbation methods, Conferences, Optimization methods, Lighting. Abstract: Deep Neural Networks are brittle in that small changes in the input can drastically affect their prediction outcome and confidence. Consequently, research in this area mainly focus on adversarial attacks and defenses. In this paper, we take an alternative stance and introduce the concept of Assistive Signals, which are perturbations optimized to improve a model’s confidence score regardless if it’s under attack or not. We analyze some interesting properties of these assistive perturbations and extend the idea to optimize them in the 3D space simulating different lighting conditions and viewing angles. Experimental evaluations show that the assistive signals generated by our optimization method increase the accuracy and confidence of deep models more than those generated by conventional methods that work in the 2D space. ‘Assistive Signals’ also illustrate bias of ML models towards certain patterns in real-life objects. |
8,330 | Please write an abstract with title: Short-term Traffic Flow Prediction based on GMO-DELM, and key words: Extreme learning machines, Atmospheric modeling, Roads, Neural networks, Predictive models, Prediction algorithms, Data models. Abstract: Short-term traffic flow prediction is the premise of making full use of intelligent transportation system and plays an important role in urban traffic planning. In this paper, a deep extreme learning machine model based on grey wolf optimizer (GWO-DELM) is proposed. The grey wolf optimizer is used to optimize the input weights of hidden layers of deep extreme learning machine to improve the prediction accuracy of the model. In order to verify the effectiveness of the model, seven data sets of M25 High-speed Heathrow Airport were used to predict the traffic flow. Compared with the existing long short-term memory network model (LSTM), BP neural network model and unoptimized deep extreme learning machine model (DELM), the results show that: The traffic flow predicted by this optimization model fits the actual traffic flow best, and the prediction error is effectively reduced. |
8,331 | Please write an abstract with title: Access Control System Based on Radioelectronic Elements and the Internet of Things, and key words: Access control, Internet of Things, Object recognition, Control systems, Software, Buildings. Abstract: The article devoted to creating a prototype of an access control and management system based on radioelectronic elements the concept of the Internet of Things. |
8,332 | Please write an abstract with title: A Distributed Face Retrieval System for Large-Scale Social Networking Avatars, and key words: Deep learning, Image recognition, Social networking (online), Avatars, Face recognition, Transforms, Feature extraction. Abstract: In order to solve the problems of poor accuracy and slow speed in face retrieval for large-scale social networking avatars, this paper proposes a real-time distributed face retrieval system supporting hundreds of millions for face images. Firstly, we detect face and learn the face feature vector by combined convolutional neural network models. Secondly, the locality sensitive hash algorithm is used to transform the high-dimensional feature into low-dimensional. Meanwhile, a distributed face feature vector database is proposed to balance the storage pressure for one single server node as well as to accelerate query speed by computing similarity score in parallel and merging sort results from all distributed server nodes. Experimental results show that the distributed system designed in this paper can efficiently, accurately and timely retrieve faces from large-scale social networking avatars. |
8,333 | Please write an abstract with title: Traffic-aware Access Control List Reconstruction, and key words: Sorting, Market research, Access control, Regression tree analysis, IP networks, Machine learning. Abstract: Access Control Lists (ACL) are configured by a net-work administrator in advance and determination of permit/deny of a packet is made based on the rule lists. The rule list is often created manually by the network administrator and the quality of an ACL depends on the skill of the network administrator. There could be redundant rules that can be integrated with other rules. Since the number of packets handled by ACL is enormous, matching process with such useless rules might cause serious performance degradation of the entire ACL. In this paper, we propose a method to reconstruct rule lists from traffic data labeled by ACL. |
8,334 | Please write an abstract with title: New technology and the need to change the focus in engineering education, and key words: Educational technology, Engineering education, Power engineering and energy, Design engineering, History, Mathematical model, Process design, Problem-solving, Portable computers, Power engineering computing. Abstract: The history of engineering is a history of the development of tools to enhance and expand the engineer's effectiveness in creating solutions to societal problems. Most of the tools have been focused on improving the engineer's ability to calculate, or to analyze mathematical models of the physical system or process under design. Since 1965, I have seen a revolution in the ability of engineers and students to perform the calculate step of the design or problem solving process. Students bring everyday to the classroom laptop computers more powerful than engineers could yet imagine 40 years ago. While this enormous power to calculate has changed how engineers think, it has not significantly changed the manner in which undergraduate engineering is taught. Engineering educators need to reconsider what is taught and how students learn in light of revolutionary and continuously changing tools for the design of new technology. |
8,335 | Please write an abstract with title: Rotated spreading sequences for broadband multicarrier-CDMA, and key words: Euclidean distance, Multicarrier code division multiple access, Detectors, Multiuser detection, Gain, Convolutional codes, Hamming distance, Phase modulation, Constellation diagram, Quadrature phase shift keying. Abstract: We present an extension of the pure Walsh-Hadamard spreading sequences for MC-CDMA. By rotating the phase of the modulated signal before spreading, the signal space is exploited more efficiently. After spreading, the Euclidean distance of each superposed constellation is distributed more favorably in the signal space than without rotating. Our novel approach combines the more favorable distributed Euclidean distance, caused by rotation, and a multiuser detector (MUD). A MUD exploits the more favorably distributed Euclidean distance, which a single-user detector, like, e.g., MMSE, is not able to do. The novel combination of these two techniques offers up to 3 dB gain for 4-QAM in comparison to the non rotated Walsh-Hadamard sequences in an MC-CDMA system. The performance gain gets lost in a coded system applying a convolutional code with a Hamming distance of ten. A gain of 1 dB can be retrieved by applying convolutional codes with higher code rates, that offer a lower Hamming distance of three for a fully loaded system. |
8,336 | Please write an abstract with title: Doppler Effect Mitigation using Reconfigurable Intelligent Surfaces with Hardware Impairments, and key words: Communication systems, Simulation, Reconfigurable intelligent surfaces, Hardware, Transceivers, Robustness, Delays. Abstract: In this paper, we analyze the effects of different types of hardware impairments (HWI), including RIS-HWI, transceiver HWI, phase quantization errors and random failures, on vehicular communication system using reconfigurable intelligent surfaces (RIS) with Doppler mitigation. A closed-form expression for the received signal-to-noise-and-distortion ratio (SNDR) of an RIS-aided vehicular communication system with HWI is derived, and we also show that the average Doppler spread can be removed completely. The simulation results validate that RIS with HWI is able to bring promising average SNDR gain (e.g, 3.16 dB) of the received signal, while eliminating the average Doppler spread, and keeping the delay spread at a very low range. As a result, using the predictable positions of the vehicle, the phase shift set of RIS can be designed in advance, such that channel estimation is not necessary, resulting in lower implementation complexity. |
8,337 | Please write an abstract with title: A Novel Heterogeneous Network for Modeling Driver Attention With Multi-Level Visual Content, and key words: Feature extraction, Semantics, Visualization, Estimation, Task analysis, Optical imaging, Object detection. Abstract: Driver attention modeling is a crucial technique in building human-centric intelligent driving systems. Considering the human visual mechanism, this study leverages multi-level visual content, including low-level texture features, middle-level optical flows, and high-level semantic information, as the model input. Subsequently, a heterogeneous model is proposed to handle the multi-level input, which integrates the graph and convolutional neural networks. Distinguished from the existing studies that use semantic segmentation, our study directly leverages the objection detection information in an interpretable manner. To deal with the detected objects, in this work, a graph attention network is used to explicitly construct the semantic information, rather than handle the features extracted by convolutional modules for building the latent space features, which are used in existing studies. Further, a semantic attention module is proposed to integrate the non-Euclidean output of the graph network with the Euclidean feature maps of the convolutional neural networks. Finally, these integrated features are decoded to generate a driver attention map. Three typical datasets are used to validate the proposed method. A comprehensive comparison and analysis have proven the feasibility and validity of our proposed method, as well as its ability to achieve state-of-the-art performance. |
8,338 | Please write an abstract with title: SpaceFibre Multi-Lane Routing Switch IP, and key words: Space missions, Satellite broadcasting, Switches, Quality of service, Routing, Throughput, IP networks. Abstract: SpaceFibre (ECSS-E-ST-50-11C) is a very high-performance, high-reliability and high-availability network technology specifically designed to meet the needs of space applications. It provides point-to-point and networked interconnections at Gigabit rates with Quality of Service (QoS) and Fault Detection, Isolation and Recovery (FDIR). SpaceFibre has been designed as a replacement of SpaceWire (ECSS-E-ST-50-12C) - it is backwards compatible with SpaceWire at the packet level - for next-generation space missions where very high throughput is required. SpaceFibre provides up to 6.25 Gbit/s per lane, with multi-lane allowing to reach up to 16 times the speed of a single lane. In this work we present the SpaceFibre Multi-Lane Routing Switch IP Core developed by STAR-Dundee and its subsidiary STAR-Barcelona. This IP provides a highly flexible router comprising a number of ports and a fully configurable, non-blocking, high performance, routing switch matrix. The internal ports use AXI4-Stream protocol, and the external ports can implement SpaceFibre or SpaceWire interfaces. The SpaceWire ports include additional bridging logic for efficient interconnection between SpaceWire and SpaceFibre equipment. The core logic of the IP is technology independent but has been optimised to be easily implemented in radiation tolerant FPGAs. The routing switch is fully compliant with all layers of the SpaceFibre standard, supporting up to 64 virtual networks and 256 broadcast channels. Among other features, it implements network time synchronisation, packet time-outs, and automatic translation between SpaceFibre broadcast messages and SpaceWire broadcast codes (SpaceWire Time-Codes or Interrupts). With up to 8 lanes per SpaceFibre interface, raw link rates of 50Gbps per port can be achieved. The multi-lane routing Switch Ip Core is implemented in the STAR-Tiger Routing Switch of the Hi-SIDE project. |
8,339 | Please write an abstract with title: Performance Analysis of Average Model of Buck Converter FED From Photo Voltaic Array Using Graphical Tool, and key words: Analytical models, Buck converters, Computational modeling, Simulation, Aerospace electronics, Tools, Market research. Abstract: In this work, DC-to-DC buck converter topology is proposed and validated. The proposed topology is incorporated the solar PV array. This paper proposed a state space average model of Buck converter which is fed from Solar PV array also circuit model of buck converter. This paper presents the proposed topology and a detailed analysis of the topology using state space averaged model and the circuit model in the LabView simulation environment. The circuit model is compared with state space model with minimum amount of voltage tolerance. The computation time with simulation is very much faster than the circuitry model time of the state. An experimental verification model has also been constructed to validate the proposed idea and the observations are presented herein. All studies have been carried out in the open loop configuration. |
8,340 | Please write an abstract with title: Unsupervised Outlier Detection in Appearance-Based Gaze Estimation, and key words: Estimation, Feature extraction, Training, Head, Testing, Lighting, Detectors. Abstract: Appearance-based gaze estimation maps RGB images to estimates of gaze directions. One problem in gaze estimation is that there always exist low-quality samples (outliers) in which the eyes are barely visible. These low-quality samples are mainly caused by blinks, occlusions (e.g. by eye glasses), blur (e.g. due to motion) and failures of the eye landmark detection. Training on these outliers degrades the performance of gaze estimators, since they have no or limited information about gaze directions. It is also risky to give estimates based on these images in real-world applications, as these estimates may be unreliable. To solve this problem, we propose an algorithm that detects outliers without supervision. Based on the input images with only gaze labels, the proposed algorithm learns to predict a gaze estimates and an additional confidence score, which alleviates the impact of outliers during learning. We evaluated this algorithm on the MPIIGaze dataset and on an internal dataset. In cross-subject evaluation, our experimental results show that the proposed algorithm results in a better gaze estimator (8% improvement). The proposed algorithm is also able to reliably detect outliers during testing, with a precision of 0.71 when the recall is 0.63. |
8,341 | Please write an abstract with title: A Non-Invasive multi-faced problem-solving tool in a Dynamic sensor network for Pediatric Diabetes with Fall Detection, and key words: Glucose, Diabetes, Insulin, Monitoring, Glucose sensors, Biomedical monitoring. Abstract: Self-management of diabetes with active involvement of family members is a well-accepted, necessary and integral part of diabetes therapy in adults. Diabetes self-management is an important and emerging concept in adolescent patients with type-1 diabetes known as T1D. In this type-1 patients, effective self-management has been shown to be positively associated with clinical outcomes. However, in adolescent T1D patients, self-management could be difficult because of the natural and evolving age-appropriate attitudes and biological factors. Despite intensive assistance and guidance from their parents is required, studies have shown lack of self-discipline and management resulting in higher haemoglobin A1c. Data management and active feedback involves the emerging sensor network using IOT technology, telemedicine and usage of social media in diabetes care for adolescents. This includes the Internet, cell phone applications and software such as Skype, Facebook, etc..Improvement in glucose control (measured with HbA1c) within 6 months with sustained improvement at the end of a year in a group of adolescent children and young adults (with T1D) has been demonstrated by applying social media. The approach to patient care in adolescent T1D is swiftly shifted by the rapid expansion of these technologies for the treatment of diabetes. Effective and practical tools to solve therapeutic problems are provided by these technologies and used to improve their quality of care and life. |
8,342 | Please write an abstract with title: Combined Random Forest and NSGA-II for Optimal Design of Permanent Magnet Arc Motor, and key words: Stator windings, Structural engineering, Analytical models, Radio frequency, Rotors, Data models, Sensitivity analysis. Abstract: This article presents an optimization design method for a double-stator hybrid excited permanent magnet arc motor (DS-HE-PMAM). The proposed optimization method combining the machine learning algorithm random forest (RF) and the nondominated sorting genetic algorithm-II (NSGA-II) contributes to achieving high average torque, low torque ripple, high back electromotive force (EMF), and low total harmonic distortion of the back EMF. First, the motor structure and working principle of the DS-HE-PMAM are illustrated. The selection of parameters to be optimized is determined based on an analytical model. Then, a variable importance measure-based new sensitivity analysis method is implemented to evaluate the influence of each structural parameter on the selected design objectives. The finite-element analysis (FEA)-based DS-HE-PMAM model is developed to obtain the sample data regarding input structural parameters and output design objectives. Based on the sample data, a powerful machine learning algorithm called RF is employed to fit the function relationship between output design objectives and input structural parameters. After that, an intelligent search algorithm named NSGA-II is introduced to search for the optimal solution to the structural parameters combination and obtain the optimal motor performances. Finally, the electromagnetic characteristics of the initial and optimized models of the DS-HE-PMAM are compared and analyzed, and both FEA and prototype experiments verify the feasibility and superiority of the proposed optimization method. |
8,343 | Please write an abstract with title: Hybrid 2/3L Inverter with Unequal PV Array Voltages, and key words: Photovoltaic systems, Voltage source inverters, Modulation, Bridge circuits, Switches, Power system harmonics, Harmonic analysis. Abstract: In Photovoltaic (PV) systems with a two-level (2L) voltage source inverter (VSI), the occurrence of partial shades and/or the mismatching of PV arrays results in poor utilization of available power. In order to overcome this issue, a new configuration known as hybrid 2/3 level (2/3L) inverter is presented in this paper. The topology is formed by adding two half bridge modules to 2L VSI. It addresses one of the common phenomena which is the unequal voltage sharing of the PV arrays addresses by a new switching sequence. This new switching sequence allows the independent operation of two PV arrays to yield maximum output. The performance of proposed hybrid 2/3L inverter configuration is studied and compared with the conventional switching sequence for varied input voltages. The effect of unequal voltage sharing in PV arrays does not reflect in the ac side waveforms when the proposed switching sequence is used and it is evident from the simulation and hardware results. |
8,344 | Please write an abstract with title: Belief Estimation by Agents in Major Minor LQG Mean Field Games, and key words: Games, Noise measurement, Sociology, Statistics, Kalman filters, Mathematical model, Standards. Abstract: Obtaining equilibria for stochastic games where agents have independent partial (noisy) observations on the system's state, and each other's control actions, is an open area for general classes of games. This is mainly because agents' strategies may depend on mutual beliefs (estimates) of the beliefs of other agents, which may subsequently lead to an infinite regress where each agent must generate an infinite sequence of mutual beliefs. Consequently finding classes of games which have partial observations and which permit tractable solutions is of significance. In this paper, a result (CDC 2015-2016) for LQG mean field game systems consisting of one major agent and a large number of minor agents where all agents have (private) partial observations is reviewed. It is one of the rare examples of a partially observed game which has a terminating (second order) belief of belief recursion. This is followed by a Nash equilibrium result for LQG mean field game systems consisting of two major agents and a large number of minor agents, where all agents have complete observations. The nature, limitations and possible extensions of this result with partial observations for all the agents are discussed. |
8,345 | Please write an abstract with title: Exploring the Relationship between Teachers' Perceptions of School Climate and Their Attitudes toward Inclusion at the Preschool Level in China, and key words: Training, Government, Information technology, Meteorology. Abstract: Individual with Disabilities Education Act (IDEA) passed by American government in 2004 revolutionized the education of children with disabilities. The IDEA requires that public schools provide specialized services to all children with disabilities from birth to age 21 for the purpose of granting equal access to education. A specific part of the law mandates public schools to create an individualized education program (IEP) for each student who is found to have an eligible disability. In China, the model of Learning in Regular Classrooms (LRC) has been implemented in primary and secondary schools for years. LRC proposes that students with mild disabilities enter regular classrooms to learn together with their typically developing peers and get necessary training and services. Little research is found concerning inclusion at the preschool level. The current study presents the demographic features of general education preschool teachers in Shanghai, China. Relationship between teachers' perceptions of school climate and their attitudes toward inclusion is investigated in order to provide supports for teachers implementing inclusion in the early childhood period. |
8,346 | Please write an abstract with title: A rate-one full-diversity low-complexity space-time-frequency block code (STFBC) for 4-Tx MIMO-OFDM, and key words: Block codes, Transmitting antennas, Decoding, Frequency diversity, Signal processing, Diversity methods, Receiving antennas, Signal design, Frequency-selective fading channels, MIMO. Abstract: It is known that by employing space-time-frequency codes (STFCs) to frequency selective MIMO-OFDM systems, all the three diversity viz spatial, temporal and multipath can be exploited. There exists space-time-frequency block codes (STFBCs) designed using orthogonal designs with constellation precoder to get full diversity (Z. Liu, Y. Xin and G. Giannakis IEEE Trans. Signal Processing, Oct. 2002). Since orthogonal designs of rate one exists only for two transmit antennas, for more than two transmit antennas STFBCs of rate-one and full-diversity cannot be constructed using orthogonal designs. This paper presents a STFBC scheme of rate one for four transmit antennas designed using quasi-orthogonal designs along with coordinate interleaved orthogonal designs (Zafar Ali Khan and B. Sundar Rajan Proc: ISIT 2002). Conditions on the signal sets that give full-diversity are identified. Simulation results are presented to show the superiority of our codes over the existing ones |
8,347 | Please write an abstract with title: Wildlife Detection and Recognition in Digital Images Using YOLOv3: Extended Abstract, and key words: Deep learning, Image recognition, Digital images, Wildlife, Hardware, Workstations, Monitoring. Abstract: Recent advances in hardware capability and machine learning techniques enable convenient monitoring of wildlife and their living environments. In this work, we apply Deep Learning (DL) methods to detect and recognize wildlife in digital images and report the experimental results conducted in a commodity workstation. Specifically, YOLOv3 and YOLOv3-Tiny are used to detect and classify several classes of animals based on 9051 digital images and they achieve 75.2% and 68.4% mean average precision, respectively. |
8,348 | Please write an abstract with title: Unsupervised learning rules for POLSAR images analysis, and key words: Unsupervised learning, Image analysis, Speckle, Layout, Integrated circuit noise, Radar signal processing, Polarimetric synthetic aperture radar, Neural networks, Data analysis, Principal component analysis. Abstract: It has been shown (see Chitroub, S. et al., Signal Processing, vol.82, no.1, p.69-92, 2002) that the model for POLSAR (polarimetric synthetic aperture radar) images is a mixture model that results from the product of two distributions, one characterizes the target response and the other characterizes the speckle phenomenon. For scene interpretation purpose, it is desirable to separate between the target response and the speckle information. We propose here to use some unsupervised learning rules for POLSAR images analysis via a PCA-ICA neural network model. Based on its rigorous statistical formulation (see Chitroub et al., Intelligent Data Analysis International Journal, vol.6, no.2, 2002), a neuronal PCA approach for the simultaneous diagonalization of the signal and noise covariance matrices is proposed. The goal is to provide PC images that are uncorrelated and have an improved SNR. Speckle is a non-Gaussian multiplicative noise, and the higher order statistics contain additional information about it. ICA is used to separate the speckle from the PC images and providing new IC images that have an improved contrast. The method has been applied on real POLSAR images. The extracted features are quite effective for scene interpretation. |
8,349 | Please write an abstract with title: MCAL: An Anatomical Knowledge Learning Model for Myocardial Segmentation in 2-D Echocardiography, and key words: Image segmentation, Myocardium, Echocardiography, Training, Shape, Convolution, Transforms. Abstract: Segmentation of the left ventricular (LV) myocardium in 2-D echocardiography is essential for clinical decision making, especially in geometry measurement and index computation. However, segmenting the myocardium is a time-consuming process and challenging due to the fuzzy boundary caused by the low image quality. The ground-truth label is employed as pixel-level class associations or shape regulation in segmentation, which works limit for effective feature enhancement for 2-D echocardiography. We propose a training strategy named multiconstrained aggregate learning (referred to as MCAL), which leverages anatomical knowledge learned through ground-truth labels to infer segmented parts and discriminate boundary pixels. The new framework encourages the model to focus on the features in accordance with the learned anatomical representations, and the training objectives incorporate a boundary distance transform weight (BDTW) to enforce a higher weight value on the boundary region, which helps to improve the segmentation accuracy. The proposed method is built as an end-to-end framework with a top-down, bottom-up architecture with skip convolution fusion blocks and carried out on two datasets (our dataset and the public CAMUS dataset). The comparison study shows that the proposed network outperforms the other segmentation baseline models, indicating that our method is beneficial for boundary pixels discrimination in segmentation. |
8,350 | Please write an abstract with title: A new robust multi-user detector based on a network of Kalman filters for non-Gaussian environment, and key words: Robustness, Detectors, Gaussian noise, Additive white noise, Multiaccess communication, Working environment noise, Equations, Multiple access interference, Testing, AWGN. Abstract: A network of Kalman filters (NKF)-based detector has recently been proposed for multiple access interference (MAI) and inter-symbols interference (ISl) compensation in DS-CDMA systems (B. Sayadi and S. Marcos, 2002). This paper presents a new structure, based on the NKF detector and on a Bayes-test for impulses localization. The resulting structure works efficiently in an "e-contaminated" noise environment. Their BER performance is near the Gaussian channel case. |
8,351 | Please write an abstract with title: Swelling Analysis of Thermal and Chemical Crosslinked Konjac Glucomannan/Gellan Gum Cardiac Patch, and key words: Heart, Cardiac tissue, Limiting, Tissue engineering, Process control, Medical treatment, Myocardium. Abstract: Cardiovascular diseases are the first cause of death worldwide. Within these, myocardial infarction is particularly limiting to patients. Although different therapies are used for myocardial infarction, the restoration of myocardial tissue and normal heart function is the desirable objective for tissue engineering. Currently, bioprinting is gaining more interest in this area for its many advantages. For this reason, we determined and compared the swelling degree and porosity of non-bioprinted and bioprinted patches. The produced patches had a high degree of swelling and exhibited very porous structures, indicating that the proposed formulation is very interesting for myocardial tissue engineering. Results also indicated that the bioprinting process allowed us to have more control over the final internal structure of the patch. |
8,352 | Please write an abstract with title: A Study on High-Efficiency Energy Detection-Based Spectrum Measurements, and key words: Time-frequency analysis, Change detection algorithms, Conferences, Signal processing algorithms, Estimation, Energy measurement, Signal processing. Abstract: Statistical information in terms of spectrum occupancy is useful for the efficient and smart dynamic spectrum sharing, and it can be obtained by long-term, broadband, and wide-area spectrum measurements. In this paper, we investigate an energy detection (ED)-based spectrum measurements, in which the noise floor (NF) estimation is a key functionality for the appropriate ED threshold setting. Typically, the NF has the slowly time- varying property and frequency-dependency, and several NF estimation algorithms, including forward consecutive mean excision (FCME) algorithm-based method, have been proposed. However, these methods did not deeply consider the slowly time varying property of the NF and is computationally inefficient. Accordingly, we propose a computational complexity reduction algorithm based on NF level change detection. This algorithm is computationally efficient, since it skips the NF estimation process when the NF does not change. In numerical evaluations, we show the efficiency and the validity of the proposed algorithm. |
8,353 | Please write an abstract with title: Improvement and Experimental Evaluation Based on ORB-SLAM-VI Algorithm, and key words: Location awareness, Visualization, Simultaneous localization and mapping, Navigation, Service robots, Robot vision systems, Feature extraction. Abstract: With the development of science and technology in recent years, SLAM technology as the intersection of robotics and computer vision has also made great progress. Based on the simultaneous localization and mapping technology of visual-inertial (ORB-SLAM-VI) tight coupling feature point information, the number of feature points that can be extracted by robots in actual scenes or low-texture environments is small, and the application scenarios are not rich enough. As well as the problem that the algorithm initialization speed is not fast enough, a tightly coupled SLAM system based on the step-by-step joint initialization of point characteristics and IMU information is proposed. The improved algorithm has been experimentally proved on the EuRoC dataset sequence to initialize the system more quickly and stably. The time is shortened by at least 2 seconds; experiments on 11 different sequences of the dataset show that compared with the VINS-Fusion and ORB-SLAM-VI algorithms, the improved algorithm is less robust for localization in stereo-IMU scenarios, but the accuracy of pose tracking and positioning is the highest. |
8,354 | Please write an abstract with title: XML policy representation for secure multicast, and key words: XML, Data security, Information security, Context, Cryptography, Authentication, Access control, Access protocols, Computer science, Software engineering. Abstract: With the wide range of communication devices being used there is a definite requirement to be able to specify security policies depending upon the context of usage, in a manner which can be easily interpreted by various devices and easily visualized by network administrators. Multicast is largely being accepted as the delivery mechanism for delivering high bandwidth content to a large number of receivers. The MSEC group within IETF has been working to develop a secure multicast framework. Their work includes the development of multicast policy architecture for interpreting, translating and representing policies. This paper shows how XML can be used for representing multicast policies. With the wide range of tools available for XML and cross-platform advantages offered by XML, it is the natural choice for policy representation. The paper also identifies various important multicast policies. |
8,355 | Please write an abstract with title: Applications of total modulation which aid the analysis of ac motors and their solid state drives, and key words: Harmonic analysis, Frequency conversion, Conductors, Angular velocity, AC motors, Windings, Coils. Abstract: There are severe limitations to the connection end location of the coils of a tutor winding so that they produce a satisfactory revolving field. The influence of these restrictions can be formulated in terms of modulating functions which yield a series of revolving field components. This technique is readily extended co solid state frequency and voltage converters in which the stator phase connections are continuously altered relative to the supply. Relationships are preserved which enable the calculation of the angular velocities and magnitudes of the revolving fields produced by a practical stator winding when excited by a fundamental and a series of harmonic voltages. Converter output voltages may be calculated and it is shown how motor currents may then be reconverted to find the supply currents. |
8,356 | Please write an abstract with title: High resolution mapping of nonlinear MHz ultrasonic fields using a scanned scatterer, and key words: Scattering, Glass, Spatial resolution, Steel, Ultrasonic variables measurement, Sonar equipment, Geometry, Robustness, Resonance, Delay. Abstract: We show that a 2 MHz HIFU field can be measured in water and with high spatial resolution by placing a small scatterer in the field and sensing the scattered wave. We use a bistatic configuration placing a hydrophone at a safe distance. Glass and steel tips are fabricated using simple techniques and evaluated. Tapered tip geometry proves to be mechanically robust and not prone to internal resonance or scattering from other sites than the tip. Glass proves to be superior to polished carbide steel in its ability to delay the initiation of cavitation, and relatively easy to manufacture using common pipette drawing technology. In our tests, a highly nonlinear 2 MHz HIFU field is mapped in degassed water with a 0.1 mm glass tip. The fundamental, 2/sup nd/, 3/sup rd/, and 4/sup th/ harmonics are mapped with at least 25 dB dynamic range and are comparable with numerical results. Numerical simulations for nonlinear fields in water are obtained using a well established KZK equation based calculation. |
8,357 | Please write an abstract with title: The library of basic components of MMIC fabricated by Istok, and key words: MMICs, Scattering parameters, Microwave FETs, Design automation, Software libraries, Microwave transistors, IEEE catalog, Pulse measurements, Circuit topology, Integrated circuit modeling. Abstract: The formation of a library of active and passive components of MMICs fabricated by "Istok" is described. The library is created for Istok's proprietary MMIC CAD software "FAGOT-M". To create the library, we chose CAD Microwave Office due to its availability and friendly user interface. Microwave Office allows the creation of user libraries in XML technology. It enables an electrical model (defined by equivalent circuit or a set of S-parameters) to be connected with each basic component. |
8,358 | Please write an abstract with title: Cloud resource prediction model based on LSTM and RBF, and key words: Backpropagation, Cloud computing, Computational modeling, Neural networks, Predictive models, Containers, Stability analysis. Abstract: In order to respond to resource usage "in advance" and to dynamically, timely and accurately schedule and allocate resources based on predicted values, a cloud resource prediction model based on Long Short Term Memory (LSTM) neural network and Radial Basis Function (RBF) neural network is proposed after investigating the current state of research on the cloud container resource prediction problem, and the parameters are trained using back propagation (BP) neural network to find the optimal combination of parameters. The LSTM can avoid the long-term dependency problem, and remembering information from very early moments is the default behavior of the LSTM without the use of a back propagation (BP) neural network. The LSTM can avoid the long-term dependency problem, and remembering information from very early moments is the default behavior of the LSTM without paying a great price for it specifically. The transformation of RBF from input space to hidden space is nonlinear, while the transformation from hidden space to output space is linear, greatly speeding up learning and avoiding the local minima problem .The experimental results show that the average error ratios of the LSTM single prediction model and RBF single prediction model are 16.38% and 19.36%, respectively, while the average error ratio of the proposed model is 4.51%, which shows that the model proposed in this paper has better prediction performance and prediction accuracy compared with other models. |
8,359 | Please write an abstract with title: Exploiting homogeneity for the optimal control of discrete-time systems: application to value iteration, and key words: Discrete-time systems, Manifolds, Heuristic algorithms, Conferences, Optimal control, Cost function, Approximation algorithms. Abstract: To investigate solutions of (near-)optimal control problems, we extend and exploit a notion of homogeneity recently proposed in the literature for discrete-time systems. Assuming the plant dynamics is homogeneous, we first derive a scaling property of its solutions along rays provided the sequence of inputs is suitably modified. We then consider homogeneous cost functions and reveal how the optimal value function scales along rays. This result can be used to construct (near-)optimal inputs on the whole state space by only solving the original problem on a given compact manifold of a smaller dimension. Compared to the related works of the literature, we impose no conditions on the homogeneity degrees. We demonstrate the strength of this new result by presenting a new approximate scheme for value iteration, which is one of the pillars of dynamic programming. The new algorithm provides guaranteed lower and upper estimates of the true value function at any iteration and has several appealing features in terms of reduced computation. A numerical case study is provided to illustrate the proposed algorithm. |
8,360 | Please write an abstract with title: Pharmacological, Non-Pharmacological Policies and Mutation: An Artificial Intelligence Based Multi-Dimensional Policy Making Algorithm for Controlling the Casualties of the Pandemic Diseases, and key words: Artificial intelligence, Pandemics, Vaccines, Parametric statistics, COVID-19, Computational modeling, Optimization. Abstract: Fighting against the pandemic diseases with unique characters requires new sophisticated approaches like the artificial intelligence. This paper develops an artificial intelligence algorithm to produce multi-dimensional policies for controlling and minimizing the pandemic casualties under the limited pharmacological resources. In this respect, a comprehensive parametric model with a priority and age-specific vaccination policy and a variety of non-pharmacological policies are introduced. This parametric model is utilized for constructing an artificial intelligence algorithm by following the exact analogy of the model-based solution. Also, this parametric model is manipulated by the artificial intelligence algorithm to seek for the best multi-dimensional non-pharmacological policies that minimize the future pandemic casualties as desired. The role of the pharmacological and non-pharmacological policies on the uncertain future casualties are extensively addressed on the real data. It is shown that the developed artificial intelligence algorithm is able to produce efficient policies which satisfy the particular optimization targets such as focusing on minimization of the death casualties more than the infected casualties or considering the curfews on the people age over 65 rather than the other non-pharmacological policies. The paper finally analyses a variety of the mutant virus cases and the corresponding non-pharmacological policies aiming to reduce the morbidity and mortality rates. |
8,361 | Please write an abstract with title: Cluster Synchronization of Two-Layer Networks via Aperiodically Intermittent Pinning Control, and key words: Synchronization, Complex networks, Delays, Couplings, Artificial intelligence, Circuits and systems, Numerical models. Abstract: As is well known, complex networks in reality are usually interconnected. To describe the interconnected networks, multiplex networks were presented recently. In this brief, an aperiodically intermittent pinning control scheme is put forward to realize cluster exponential synchronization in a two-layer (leader-follower) network with multi-links and time-varying delays. Based on the principle of intermittent control and Lasalle invariant principle, some criteria for cluster synchronization are deduced by theoretical analysis. Numerical simulations are provided to verify the effectiveness of the proposed scheme. In comparison with the previous methods, our model better describes the real-world networks and our control effectively reduces the control cost. |
8,362 | Please write an abstract with title: Research of cooperative product design based on a rapid inducing solid model, and key words: Product design, Solid modeling, History, Displays, Shape, Design automation, Geometry, Computer aided manufacturing, CADCAM, System testing. Abstract: Web-based interactive design always brings out mass of data transferring and makes it difficult to display real-time model. In order to decrease transferring data, a model called RISM (rapid inducing solid model) is provided to build the shape representation and operation structure. Based on the structure, an operation history tree is built by extending traditional CSG model. Then traditional product CAD model is divided into two parts in RISM, one is displaying model contained surface attributes for product design and run in client, the other is represented model contained geometry attributes for transforming to CAM model and running in server. According to the idea, RISM structure is built to construct CSG-based operations history tree. Then based on RISM common operations set and RISM message mechanism, a CSCD framework is proposed. Therefore, displaying model and representation model could work individually and integrate in one united body. At last, a cooperative design system based on ACIS is implemented for testing. It is shown that the RISM enhance design system effectively by decreasing transferring data largely, and the model provides a new framework to realize distributed Web application. |
8,363 | Please write an abstract with title: Using Communication Networks to Predict Team Performance in Massively Multiplayer Online Games, and key words: Machine learning algorithms, Social networking (online), Games, Virtual groups, Predictive models, Communication networks, Task analysis. Abstract: Virtual teams are becoming increasingly important. Since they are digital in nature, their “trace data” enable a broad set of new research opportunities. Online Games are especially useful for studying social behavior patterns of collaborative teams. In our study we used longitudinal data from the Massively Multiplayer Online Game (MMOG) Travian collected over a 12-month period that included 4,753 teams with 18,056 individuals and their communication networks. For predicting team performance, we selected 13 SNA-based attributes frequently used in team and leadership research. Using machine learning algorithms, the added explanatory power derived from the patterns of the communication networks enabled us to achieve an adjusted R2 = 0.67 in the best fitting performance prediction model and a prediction accuracy of up to 95.3% in the classification of top performing teams. |
8,364 | Please write an abstract with title: Distributed Cross-Relation-Based Frequency-Domain Blind System Identification Using Online-Admm, and key words: Wireless sensor networks, Frequency-domain analysis, Signal processing algorithms, Channel estimation, Adaptive algorithms, SIMO communication, Convex functions, Steady-state, System identification, Convergence. Abstract: In this paper, we propose a distributed cross-relation-based adaptive algorithm for blind identification of single-input multiple-output (SIMO) systems in the frequency domain, using the alternating direction method of multipliers (ADMM) in a wireless sensor network (WSN). The network consists of a fixed number of nodes each equipped with a processing unit and a sensor that represents an output channel of the SIMO system. The proposed algorithm exploits the separability of the cross-channel relations by splitting the multichannel identification problem into sub-problems containing a subset of channels, in a way that is determined by the network topology. Each node delivers estimates for the subset of channel frequency responses, which are then combined into a consensus estimate per channel using general-form consensus ADMM in an adaptive updating scheme. Using numerical simulations, we show that it is possible to achieve convergence speeds and steady-state misalignment values comparable to fully centralized low-cost frequency-domain algorithms. |
8,365 | Please write an abstract with title: Fall Detection for Elderly Person Monitoring using Wearable Inertial Sensors and Locality Sensitive Hashing, and key words: Accelerometers, Energy consumption, Three-dimensional displays, Sensitivity, Inertial sensors, Computational modeling, Gyroscopes. Abstract: Falling represents the main threat for elderly people. An early detection mechanism is crucial to assist the person and prevent further injuries from concussion to underlying pain from fractures. In this paper, we propose a new model for fall detection to improve the detection accuracy and to reduce the detection delay, while considering detection processing in the sensor to reduce the energy consumption by wireless transmission of Inertial data from sensor to processing unit. Our proposed approach is based on change detection in the slope of angular velocity, which enhances the sensitivity and drastically reduces the detection delay. After the detection of change, the local sensitivity hashing is applied to detect change in the amplitude of accelerometer signal. We applied our multimodal system on publicly available data set built for fall detection during daily activities. The proposed approach uses only data from 3D gyroscope and 3D accelerometer acquired by inertial sensor from different positions: ankle, wrist, waist, pocket, neck and forehand. Our experiment results show that our proposed model achieves high detection accuracy with low false alarms when compared to existing work in the literature. Furthermore, we compare our approach with existing work in terms of computational complexity and detection delay to prove that it reduces the energy consumption and achieve better performance than existing models. |
8,366 | Please write an abstract with title: Expiration Times for Data Management, and key words: Web services, Synchronization, Costs, Computer science, Relational databases, Data models, Algebra, Fires, Layout, Transaction databases. Abstract: This paper describes an approach to incorporating the notion of expiration time into data management based on the relational model. Expiration times indicate when tuples cease to be current in a database. The paper presents a formal data model and a query algebra that handle expiration times transparently and declaratively. In particular, expiration times are exposed to users only on insertion and update, and when triggers fire due to the expiration of a tuple; for queries, they are handled behind the scenes and do not concern the user. Notably, tuples are removed automatically from (materialised) query results as they expire in the (base) relations. For application developers, the benefits of using expiration times are leaner application code, lower transaction volume, smaller databases, and higher consistency for replicated data with lower overhead. Expiration times turn out to be especially useful in open architectures and loosely-coupled systems, which abound on the World Wide Web as well as in mobile networks, be it as Web Services or as ad hoc and intermittent networks of mobile devices. |
8,367 | Please write an abstract with title: On the investigation of gate metal interdiffusion in GaAs HEMTs, and key words: Gallium arsenide, HEMTs, MODFETs, MESFETs, Thermal degradation, Indium gallium arsenide, Scanning electron microscopy, Gold, Metallization, Transmission electron microscopy. Abstract: Ti interdiffusion of Ti/Pt/Au gate metal stacks in 0.15 /spl mu/m GaAs HEMTs subjected to high-temperature lifetest has been physically identified using STEM technique. Further EDX analysis substantiates the intermetallic formation of Ti-AlGaAs and Ti sinking into the AlGaAs Schottky barrier layer. Ti interdiffusion reduces the separation of the gate metal and InGaAs channel, thus leading to the evolution of a slight Gm increase, positive shift of pinchoff voltage, and S21 increase during the initial stage of lifetest. The STEM was further used to correlate Ti-InGaAs-channel-separation and Ti-sinking depth with a device parameter, Vgs - an indicator of Ti-InGaAs-channel-separation. It has been discovered that Ti-sinking-depth is insensitive to Vgs. However, as Ti interdiffuses, the separation of, the gate metal and InGaAs channel is decreased, therefore affecting the Idss degradation rate. As a result, we observe the dependence of /spl Delta/Idss on Vgs. The results provide insight into a critical parameter, Vgs, for optimizing reliability performance based on /spl Delta/ldss. |
8,368 | Please write an abstract with title: Resource Allocation of Multi-Cell Full-Duplex Networks Based on Ant Colony Optimization, and key words: Interference, Resource management, Uplink, Downlink, Power control, Ant colony optimization, Zirconium. Abstract: Full-duplex (FD) communication enables a device to transmit and receive at the same time and on the same frequency. It has the potential to double the capacity of the half-duplex (HD) system. In a multiuser system, however, FD could also double the interference between users which hinders improvement of the capacity. In this paper, we consider resource allocation in a FD multi-cell system to mitigate the interference and exploit the potential gain of FD communication. Due to high complexity of the problem, an ant colony optimization (ACO) based algorithm is proposed to obtain a good performance with reasonable complexity. To the best of our knowledge, the proposed method is the first real multi-cell ACO in the literature applied to a system that allows FD and HD switching. Simulation results show that the proposed algorithm outperforms an existing greedy search method when the number of resource blocks becomes large and the optimization problem becomes complex. By combining the advantages of the ACO algorithm and greedy search, the resultant algorithm yields an even better performance. |
8,369 | Please write an abstract with title: Research on the Application of Software Development Mode on Reusable Framework based on Neural Network Algorithm, and key words: Analytical models, Costs, Computational modeling, Scalability, Software algorithms, Stochastic processes, Software. Abstract: The framework is a semi-finished product of reusable application software in a specific field. Developers can build specific application systems through customization. A good framework can greatly reduce the development cost of the application system. From the perspective of the reusable framework, this paper applies the improved stochastic gradient learning algorithm to the software development of the reusable framework. The article first designed two model structures of convolutional neural network and multi-layer feedforward network to analyze the software development model based on this, hoping to promote the improvement of software development quality and efficiency by 6.8%. |
8,370 | Please write an abstract with title: Research on Operation Index Management of Communication Network, and key words: Conferences, Indexes, Communication networks, Software engineering. Abstract: With the application of a large number of new technology and equipment and the expansion of network scale, at present, the content and form of communication network operation index management have undergone tremendous changes. This paper mainly studies the current situation and related advanced technology of communication network operation index, introduces the management scope and content of communication network operation index in detail, and expounds the application and implementation process of communication network operation index management system. |
8,371 | Please write an abstract with title: Dynamic and vibration modeling of a cartesian robot, and key words: Robots, Robotic assembly, Actuators, Friction, Control system synthesis, Voltage, Resonance, Predictive models, Assembly systems, Testing. Abstract: Quality of the dynamic response of a robotic manipulator is dependent upon a variety of factors. In this paper, we will discuss the effects on dynamic performance of robot system design and of structural resonant characteristics. A model of the actuator and controller system for a cartesian robot will be presented and its simulated performmance evaluated. Comparison will be made between performance of the model and that of the actual robot system. A model for system resonant characteristics will then be developed and predictions compared with experimental data. |
8,372 | Please write an abstract with title: Impact of the modulation instability on supercontinuum generation, and key words: Supercontinuum generation, Optical fiber dispersion, Four-wave mixing, Optical fibers, Raman scattering, Frequency, Solitons, Pulse generation, Photonic crystal fibers, Optimized production technology. Abstract: We discuss the combination of soliton fission, induced by third-order dispersion, and modulation instability. Furthermore, we investigate the impact of fourth-order dispersion on the modulation instability in the case of normal dispersion. The overall observed behavior of SC generation turns out to be primarily determined by the modulation instability. Because higher-order effects are not a prerequisite for the generation of supercontinuum, it is not restricted only to ultrashort sub-picosecond pulses, hut appears for much longer pulses too. It can also appear in the normal dispersion regime /spl beta//sub 2/ > 0, if the fourth-order dispersion coefficient /spl beta//sub 4/ is negative. |
8,373 | Please write an abstract with title: Reconfigurable Intelligent Surface Aided Cell-Free MIMO Communications, and key words: Array signal processing, Optimization, MIMO communication, Three-dimensional displays, Resource management, Transmitting antennas, Simulation. Abstract: Cell-free system is an efficient solution to eliminate inter-cell interference by serving users without cell boundaries. To further improve the spectrum efficiency, in this letter, we consider a reconfigurable intelligent surface (RIS) aided cell-free MIMO system. Multiple RISs are employed to create favorable propagation conditions via configurable reflection from the BS to users. Benefited from multiple transmission paths the spatial resources can be better utilized. We develop a hybrid beamforming (HBF) scheme consisting of the digital beamforming at the BS and the RIS-based beamforming. A sum rate optimization (SRO) problem is formulated and an iterative algorithm is designed to solve this problem. Simulation results show that the proposed system can achieve a significant performance gain compared to conventional single cell systems without RISs and distributed antenna systems. |
8,374 | Please write an abstract with title: An Efficient Bayesian Neural Network for Multiple Data Streams, and key words: Connectors, Costs, Neural networks, Training data, Machine learning, Real-time systems, Spatial databases. Abstract: Spatial and temporal data such as multiple data streams often have concept drift problems, which refers to changes of the data distributions over time. Once concept drift occurs, a stationary machine learning predictor will probably be invalid because the testing data have a different data distribution from that of the training data. Recent studies in data streams aim to address this issue by concept drift adaptation techniques. Concept drift adaptation methods update the predictor by time and have been validated to provide accurate real-time prediction for a single data stream. However, handling multiple relevant data streams is still an unsolved challenge in this area, considering many real-world applications generate multiple data streams that are simultaneously evolving. To fill this gap, we here present a predicting network for multiple data streams, named MuNet. MuNet leverages the dependency between data streams to efficiently lower down the computational cost of real-time predictions for multiple data streams. In MuNet, an online-learned Bayesian neural network (BNN) is designed as a connector between streams. The BNN-connector can continuously use the real-time information from only one base stream to correct the stationary predictor for the other streams, which avoids the high cost caused by repeated adaptation. |
8,375 | Please write an abstract with title: A Compact Optical Fiber Sagnac Loop Inserting With A Nematic Liquid Crystal Film for Highly Sensitive Temperature Sensing, and key words: Temperature sensors, Interference, Sagnac interferometers, Temperature measurement, Sensitivity, Temperature dependence, Fabry-Perot. Abstract: Since the high temperature response characteristics of nematic liquid crystal (NLC) molecules, a compact optical fiber Sagnac loop inserted a segment of NLC film for temperature sensing was proposed and experimentally demonstrated. The NLC film was formed by filling into the micron-scale gap between the two single-mode fibers inserted into a ferrule matching sleeve. After two single-mode patch cables were rotated, the NLC film molecules were oriented due to exogenous effects. Experimental results showed that the temperature sensing performance of the designed sensor was improved by decreasing the thickness of NLC film in Sagnac loop. The thickness of NLC film in the ferrule matching sleeve was measured accurately by Fabry-Perot interference. The wide temperature measurement range of 2.2 ∼ 50.2 °C and a high temperature sensitivity of -9.34 nm/°C were achieved at the NLC film thickness of 31.30 μm. Owing to the compact structure, large measurement range, and high sensitivity, the designed sensor shows a broad application prospect in high spatial resolution and high sensitivity temperature sensing. |
8,376 | Please write an abstract with title: An application of cathodoluminescence to optimize the shallow trench isolation process, and key words: Spectroscopy, Testing, Scanning electron microscopy, Large scale integration, Transmission electron microscopy, Crystallization, Failure analysis, Leakage current, Optical films, Optical microscopy. Abstract: Cathodoluminescence (CL) spectroscopy was applied to optimize the shallow trench isolation (STI) process. The analysis of dislocations with CL spectroscopy could be performed during STI process steps. Then, the result of CL analysis was associated with the failure of a junction leakage current. Moreover, the analysis contributed to identifying the failure, including the root cause. As the result of CL analysis, nitride film thickness used as a mask layer of patterning was controlled at 190 nm or less. The dislocation analysis with CL spectroscopy can reduce the cycle time from 50 to 5 days. |
8,377 | Please write an abstract with title: Co-Design of Consensus-Based Approach and Reliable Communication Protocol for Vehicular Platoon Control, and key words: Topology, Network topology, Reliability, Delays, Protocols, Sensors, Control systems. Abstract: Automated and coordinated vehicle platoon driving is challenging as the complexity of vehicle control and the presence of unreliable wireless inter-vehicle communication. This subject has an interdisciplinary nature, involving control theories, vehicle dynamics, and communication. Due to the constant interaction between control logic and communication topology, a co-design approach for the controller and for reliable communication protocol becomes necessary. This paper describes the AddP-CACC - a consensus-based solution to vehicle platoons. The proposed solution turns the communication topology into a design parameter that dynamically reconfigures the controller. In addition, the controller automatically compensates for outdated information caused by network losses and delays. AddP-CACC was implemented in the PLEXE tool and was compared with other related works. Simulation results have shown the robustness and performance of the proposed solution in various scenarios that would include realistic propagation conditions with interference caused by other vehicles. The results have also evidenced the ability of the proposed solution to maintain a stable vehicular platoon by using different communication topologies, different vehicle flows, even in the presence of strong interferences, delays, and fading conditions. |
8,378 | Please write an abstract with title: Regulating Metabolic Energy Among Joints During Human Walking Using a Multiarticular Unpowered Exoskeleton, and key words: Exoskeletons, Hip, Knee, Legged locomotion, Muscles, Recycling, Energy exchange. Abstract: Researchers have found that the walking economy can be enhanced by recycling ankle metabolic energy using an unpowered ankle exoskeleton. However, how to regulate multiarticular energy to enhance the overall energy efficiency of humans during walking remains a challenging problem, as multiarticular passive assistance is more likely to interfere with the human body's natural biomechanics. Here we show that the metabolic energy of the hip and knee musculature can be regulated to a more energy-effective direction using a multiarticular unpowered exoskeleton that recycles negative mechanical energy of the knee joint in the late swing phase and transfers the stored energy to assist the hip extensors in performing positive mechanical work in the stance phase. The biarticular spring-clutch mechanism of the exoskeleton performs a complementary energy recycling and energy transfer function for hip and knee musculature. Through the phased regulation of the hip and knee metabolic energy, the target muscle activities decreased during the whole assistive period of the exoskeleton, which was the direct reason for 8.6 ± 1.5% (mean ± s.e.m) reduction in metabolic rate compared with that of walking without the exoskeleton. The proposed unpowered exoskeleton enhanced the user's multiarticular energy efficiency, which equals improving musculoskeletal structure by adding a complementary loop for efficient energy recycling and energy transfer. |
8,379 | Please write an abstract with title: Joint Segmentation and Uncertainty Estimation of Ventricular Structures from Cardiac MRI using a Bayesian CondenseUNet, and key words: Training, Image segmentation, Uncertainty, Computational modeling, Magnetic resonance imaging, Pipelines, Neural networks. Abstract: While convolutional neural networks (CNNs) have shown potential in segmenting cardiac structures from magnetic resonance (MR) images, their clinical applications still fall short of providing reliable cardiac segmentation. As a result, it is critical to quantify segmentation uncertainty in order to identify which segmentations might be troublesome. Moreover, quantifying uncertainty is critical in real-world scenarios, where input distributions are frequently moved from the training distribution due to sample bias and non-stationarity. Therefore, well-calibrated uncertainty estimates provide information on whether a model's output should (or should not) be trusted in such situations. In this work, we used a Bayesian version of our previously proposed CondenseUNet [1] framework featuring both a learned group structure and a regularized weight-pruner to reduce the computational cost in volumetric image segmentation and help quantify predictive uncertainty. Our study further showcases the potential of our deep-learning framework to evaluate the correlation between the uncertainty and the segmentation errors for a given model. The proposed model was trained and tested on the Automated Cardiac Diagnosis Challenge (ACDC) dataset featuring 150 cine cardiac MRI patient dataset for the segmentation and uncertainty estimation of the left ventricle (LV), right ventricle (RV), and myocardium (Myo) at end-diastole (ED) and end-systole (ES) phases. |
8,380 | Please write an abstract with title: Towards making big data applications network-aware in edge-cloud systems, and key words: Task analysis, Servers, Delays, Topology, Network topology, Data centers, Bandwidth. Abstract: The amount of data collected in various IT systems has grown exponentially in the recent years. So the challenge rises how we can process those huge datasets with the fulfillment of strict time criteria and of effective resource consumption, usually posed by the service consumers. This problem is not yet resolved with the appearance of edge computing as wide-area networking and all its well-known issues come into play and affect the performance of the applications scheduled in a hybrid edge-cloud infrastructure. In this paper, we present the steps we made towards network-aware big data task scheduling over such distributed systems. We propose different resource orchestration algorithms for two potential challenges we identify related to network resources of a geographically distributed topology: decreasing end-to-end latency and effectively allocating network bandwidth. The heuristic algorithms we propose provide better big data application performance compared to the default methods. We implement our solutions in our simulation environment and show the improved quality of big data applications. |
8,381 | Please write an abstract with title: R&D towards cooling of the RHIC collider, and key words: Research and development, Cooling, Colliding beam accelerators, Ion accelerators, Linear particle accelerator, Electron beams, Energy storage, Electron sources, Radio frequency, Cathodes. Abstract: We introduce the R&D program for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This electron cooler is designed to cool 100 GeV/nucleon bunched-beam ion collider at storage energy using 54 MeV electrons. The electron source will be an RF photocathode gun. The accelerator will be a superconducting energy recovery linac. The frequency of the accelerator is set at 703.75 MHz. The maximum bunch frequency is 28.15 MHz, with bunch charge of 10 nC. The R&D program has the following components: The photoinjector, the superconducting linac, start-to-end beam dynamics with magnetized electrons, electron cooling calculations and development of a large superconducting solenoid. |
8,382 | Please write an abstract with title: An iterative method to restore the performance of clipped and filtered OFDM signals, and key words: Iterative methods, Signal restoration, OFDM, Peak to average power ratio, Additive white noise, Gaussian noise, Noise cancellation, Nonlinear distortion, Signal to noise ratio, Bandwidth. Abstract: Clipping is an efficient and simple method to reduce the peak-to-average power ratio (PAPR) of OFDM signals. However, clipping causes distortion and out-of-band radiation. In this paper, a novel iterative receiver is proposed to estimate and cancel the distortion caused by clipping noise. The proposed method is applied to clipped and filtered OFDM signals. It is shown by simulation that for an 802.11a system, the PAPR can be reduced to as low as 4 dB while the system performance can be restored to within 1 dB of the non-clipped case with only moderate complexity increase and with no bandwidth expansion. |
8,383 | Please write an abstract with title: Joint Radar-Communication Strategies for Autonomous Vehicles: Combining Two Key Automotive Technologies, and key words: Radar antennas, Automotive engineering, OFDM, Autonomous vehicles, Frequency division multiplexing, Radar detection. Abstract: Self-driving cars constantly assess their environment to choose routes, comply with traffic regulations, and avoid hazards. To that aim, such vehicles are equipped with wireless communications transceivers as well as multiple sensors, including automotive radars. The fact that autonomous vehicles implement both radar and communications motivates designing these functionalities in a joint manner. Such dualfunction radar-communications (DFRC) designs are the focus of a large body of recent work. These approaches can lead to substantial gains in size, cost, power consumption, robustness, and performance, especially when both radar and communications operate in the same range, which is the case in vehicular applications. |
8,384 | Please write an abstract with title: Bounds on the Spectral Radius of Nonnegative Matrices, and key words: Eigenvalues and eigenfunctions, Computer science, Biomedical informatics, Laplace equations, Symmetric matrices, Upper bound, Linear matrix inequalities. Abstract: In this paper, we determine some new bounds for the spectral radius of a nonnegative matrix with respect to the upper and the lower bounds for the spectral radius given by Frobenius' bounds, by using similarity transformations. We also provide illustrative examples in order to compare the new bounds with the existing ones. |
8,385 | Please write an abstract with title: Simulation for Fault Forbearance Operation for Three-Phase Three-level H-Bridge Multilevel Inverter by Space Vector Modulation technique, and key words: Switches, Inverters, Circuit faults, Capacitors, Legged locomotion, Modulation, Fault tolerance. Abstract: This paper represents the fault tolerance technique of three-phase three-level H-Bridge Multilevel inverter. Near about equal output voltages are generated in single fault and pre-fault conditions. Regardless of the appearance of fault location and its class, three-phase balanced voltage is generated with its peak amplitude. The auxiliary module is connected which is voltage source two-level inverter along with a dc capacitive link. After fault detection, the auxiliary module gets activated and the capacitor charging and discharging starts and then the voltage across the auxiliary module is constant and the reference Vector is synchronized. The validation of the proposed technique is affirmed by simulations on a three-level H-Bridge for three-phase Inverters. |
8,386 | Please write an abstract with title: A monopole ultrasonic pulse generator using PVDF piezoelectric film, and key words: Pulse generation, Piezoelectric films, Voltage, Acoustic pulses, Space vector pulse width modulation, Current measurement, Dielectric measurements, Charge measurement, Pressure measurement, Pulse measurements. Abstract: In this paper, a monopole ultrasonic pulse generator driven by a step-function voltage with a fast falling time is presented. We consider that the waveform and the pulse width of the ultrasonic is decided by the thickness of PVDF piezoelectric film transducer, the falling time of step-function voltage, the backing and the shape of acoustic propagation medium. The pulse generator is suitable to use for measuring the space charge distribution in solid dielectric, the width of pressure pulse is about 50 ns. It is also suitable for the other applications, e.g., the ultrasonic medical diagnosis. All these results are acquired through the piezo-PWP (Pressure Wave Propagation) measuring system applied for the study of space charge. |
8,387 | Please write an abstract with title: A Modified Weighting Scheme for the Automatic Tasker of Space Surveillance Network, and key words: Space vehicles, Geometry, Satellites, Uncertainty, Surveillance, Orbits, Stability analysis. Abstract: The increasing number of space objects rapidly consumes the limited resources of space surveillance system. Improving the observation efficiency of sensors can alleviate the strain of the Space Surveillance Network (SSN). In this paper, we provide a modified weighting scheme for observation scheduling of automatic tasker of SSN. We analyze the influence of observation geometry, observation time and observation distribution in scheduling time span on orbit determination accuracy based on the covariance of relative orbit uncertainty in satellite orbit determination, and then provide a weighting scheme of the SSN automated tasker for SSN to improve the observation efficiency. Finally, the feasibility of this weighting scheme under limited resources is simulated and compared with the reported ones. |
8,388 | Please write an abstract with title: Free-space optical communication through atmospheric turbulence channels, and key words: Optical fiber communication, Fading, Fluctuations, Statistics, Diversity reception, Optical receivers, Apertures, Detectors, Maximum likelihood detection, Costs. Abstract: In free-space optical communication links, atmospheric turbulence causes fluctuations in both the intensity and the phase of the received light signal, impairing link performance. We describe several communication techniques to mitigate turbulence-induced intensity fluctuations, i.e., signal fading. These techniques are applicable in the regime in which the receiver aperture is smaller than the correlation length of fading and the observation interval is shorter than the correlation time of fading. We assume that the receiver has no knowledge of the instantaneous fading state. When the receiver knows only the marginal statistics of the fading, a symbol-by-symbol ML detector can be used to improve detection performance. If the receiver has knowledge of the joint temporal statistics of the fading, maximum-likelihood sequence detection (MLSD) can be employed, yielding a further performance improvement, but at the cost of very high complexity. Spatial diversity reception with multiple receivers can also be used to overcome turbulence-induced fading. We describe the use of ML detection in spatial diversity reception to reduce the diversity gain penalty caused by correlation between the fading at different receivers. |
8,389 | Please write an abstract with title: Edge connector for mechanical and electrical interconnection of PCBs, and key words: Connectors, Integrated circuit interconnections, Manufacturing, Prototypes, Electronic equipment testing, Circuit testing, System testing, Assembly systems, Printed circuits, Costs. Abstract: The goals of the work introduced in this article are the development, manufacturing and testing of a three-dimensional (3D) modular system for electronic prototyping allowing for a fast, efficient and modular assembling of electronic systems dealing with a high volume of interconnections. This system uses a special kind of connector manufactured straight on the printed circuit board edge which highly reduces the surface required for the interconnection and also the final cost of the system. The Proto3D system will be very useful for educational and research purposes and also for small and medium size companies which will have fully functional prototypes for complex electronic systems in a few days term. |
8,390 | Please write an abstract with title: A High-Efficient Hybrid Physics-Informed Neural Networks Based on Convolutional Neural Network, and key words: Neural networks, Machine learning, Training, Learning systems, Inverse problems, Handheld computers, Geometry. Abstract: In this article, we develop a hybrid physics-informed neural network (hybrid PINN) for partial differential equations (PDEs). We borrow the idea from the convolutional neural network (CNN) and finite volume methods. Unlike the physics-informed neural network (PINN) and its variations, the method proposed in this article uses an approximation of the differential operator to solve the PDEs instead of automatic differentiation (AD). The approximation is given by a local fitting method, which is the main contribution of this article. As a result, our method has been proved to have a convergent rate. This will also avoid the issue that the neural network gives a bad prediction, which sometimes happened in PINN. To the author’s best knowledge, this is the first work that the machine learning PDE’s solver has a convergent rate, such as in numerical methods. The numerical experiments verify the correctness and efficiency of our algorithm. We also show that our method can be applied in inverse problems and surface PDEs, although without proof. |
8,391 | Please write an abstract with title: Phase differential angular rate sensor-concept and analysis, and key words: Phase detection, Force sensors, Shape, Sensor systems, Gyroscopes, Microelectromechanical systems, Micromechanical devices, Application software, Biosensors, Navigation. Abstract: This paper proposes and analyzes a new differential phase angular rate (AR) sensor employing a vibrating beam mass structure that traces an elliptical path when subject to rotation due to Coriolis force. Two sensing elements are strategically located to sense a combination of drive and Coriolis vibration to create a phase differential representative of the input rotation rate. A general model is developed, describing the device operation. The main advantages of the phase detection scheme are explored, including removing the need to maintain constant drive amplitude, independence of sensing element gain factor, and advantageous response shapes. A ratio of device parameters is defined and shown to dictate the device response shape. This ratio can be varied to give an optimally linear phase difference output over a set input range, a high sensitivity around zero input rate, or a response shape not seen before, that can give maximum sensitivity around an offset from the zero-rate input. This may be exploited in an array configuration for a highly accurate device over a wide input range. A worked example shows how the developed equations can be used as design tools to achieve a desired response with low sensitivity to variation in device parameters. |
8,392 | Please write an abstract with title: Roles of Mobilized Controls and Environmental Uncertainty on Supply Chain Resilience: An Empirical Study From Dynamic-Capabilities-View and Levers-of-Control Perspectives, and key words: Uncertainty, Supply chains, COVID-19, Resilience, Interactive systems, Control systems, Companies. Abstract: COVID-19 creates big challanges to supply chain management. This article empirically examines the impact of management control systems (MCS) on managing supply chain resilience (SCR) to enhance organizational competitiveness under environmental uncertainty. Drawing on the dynamic capabilities view (DCV) theory and levers of control (LoC) framework, an industrial survey was conducted. Analyses performed on the collected data from 405 manufacturing firms reveal that the effects of MCS on SCR and organizational competitiveness depend on the nature and use of mobilized controls. Different from conventional wisdom, the study suggests that belief, boundary, and interactive systems enable firms to achieve SCR and these systems have positive effects on organizational competitiveness through SCR. Moreover, interestingly, diagnostic systems seem to play no role in strengthening SCR and organizational competitiveness. The study thus argues that firms should employ the enabling characteristics of belief and interactive systems, along with the controlling features of boundary systems to manage SCR and ultimately be more organizational-competitive. The research also uncovers that environmental uncertainty positively moderates the indirect effects of MCS on organizational competitiveness through SCR. Indeed, the study indicates that firms evolving in highly uncertain and dynamic environments tend to increase the use of different MCS to generate detailed information that is essential to strengthen SCR. Overall, this theory-based empirical research provides novel insights regarding how MCS would contribute to improving SCR and organizational competitiveness, especially under disruptions such as COVID-19. |
8,393 | Please write an abstract with title: EPCA basaed Modal Parameters Identification with Test data, and key words: Vibrations, Information science, Parameter estimation, Control engineering, Shape, Market research, Time factors. Abstract: During the process of modal parameters identification by traditional principal component analysis (PCA), to reduce the effects of the magnitude influence of response data on different discrete points, a method of identifying modal parameters from test data based on equalization PCA (EPCA) is proposed in this paper. The basic idea of this method is equalizing the test data before identifying modal parameters by PCA. Besides, to decrease the undesirable influence of the trend in the test data, we will first remove the trend in the response data. To verify the method proposed in this paper, two different beams’ modal tests have been taken. The modal parameters have been obtained by the modal tests and the response data with different points has been collected either. The modal parameters are identified by traditional PCA and EPCA with the same constraints of principal component cumulative contribution rate with the response data. The results show that, compared with the traditional PCA, the modal shapes identified by EPCA are more similar to the modal shapes obtained by the modal tests. |
8,394 | Please write an abstract with title: GSketch: A Comprehensive Graph Analytic Approach for Masquerader Detection Based on File Access Graph, and key words: Computers, Organizations, Feature extraction, Security, Detection algorithms. Abstract: Masqueraders are a severe insider threat and have become a conventional security issue for most organizations. The majority of existing techniques for detecting masqueraders extract statistical features from file access logs. However, the graph's features from these logs have not been fully explored. In this work, we introduce GSketch. First, it divides each user's file access logs into equal length, non-overlapping time windows. Then file access logs on each time window are transformed into a graph according to chronological order. GSketch extracts global features and local features from the graph. Global features provide a panoramic view of the graph, and local features mine small, induced sub-graphs. Finally, GSketch applies an abnormal detection algorithm to find anomalous points in the feature space and marks these points as masquerader's activities. The effectiveness of GSketch is demonstrated by its excellent performances on two public datasets - WUIL and TWOS. |
8,395 | Please write an abstract with title: Electric Strain Gauges Method in the Effectiveness Assessment for the C-Frame Crank Press Elastic Compensators, and key words: Temperature measurement, Presses, Temperature distribution, Temperature dependence, Tensile stress, Bridge circuits, Strain measurement. Abstract: The electric strain gauges method application to the elastic compensators effectiveness assessment for the "press-die" system of C-frame (gap-frame) presses is shown. The electric Wheatstone bridge was adapted, where the one arm is used on the equal mechanical stress calibration beam, and the other arm on the section of the press frame, which experiences maximum tensile stresses. The bridge arms' active and ballast purpose changed during calibration and research. After receiving the calibration characteristic between the current on the ammeter and mechanical stresses, the stress level in the press frame was estimated using various elastic compensators aimed at reducing them. It is shown that the use of elastic compensators based on polyurethane elastomers can reduce parasitic loads in the press frame by 15-42% compared to tensile stresses arising in the frame without a compensator. It has been established that the highest compensators efficiency is observed in the range of their upsetting up to 20-30%. |
8,396 | Please write an abstract with title: Quantum state storage and reconstruction in solids, and key words: Absorption, Material storage, Optical materials, Optical pumping, Solid state circuits, Shape, Frequency, Background noise, Noise level, Phase noise. Abstract: A scheme for highly efficient storage and recall of single- and few-photon wave-packets in solid state materials (here inorganic crystals doped with rare-earth ions) is presented. The scheme is supported by experimental data showing that single-photon absorption effects can be observed in these materials and also how the materials can be tailored for the quantum state storage and reconstruction operation using suitably selected excitation pulses. |
8,397 | Please write an abstract with title: Computer Aided Mass Detection in Mammograms, and key words: Solid modeling, Quantization (signal), Image recognition, Design automation, Force, Feature extraction, Delta-sigma modulation. Abstract: Radiologist's expertise in identifying and sleuthing breast cancer can be helped by utilizing some modernized feature extraction and classification techniques. In the proposed Computer Aided Diagnosis (CAD) framework, different techniques have been utilized. Pre-processing of mammograms is performed to stifle the noise present in the mammograms. The images are classified as low dense and high dense. Feature extraction is carried out to recognize the significant and vital parts from the image utilizing the techniques namely Local Phase Quantization (LPQ), Local Binary Pattern (LBP), and Gray- Level Co-Occurrence Matrix (GLCM) for both high dense and low dense images. Experiments were done using the 2749 images from the DDSM dataset. The outcomes exhibited the adequacy of the proposed framework and show the imperativeness for clinical applications. |
8,398 | Please write an abstract with title: Evaluation of Performance Bounds in Distributed Detection, and key words: Quantization (signal), Error probability, Computational modeling, Europe, Microcomputers, Computational complexity. Abstract: A generalized version of the majority voting rule is proposed to speed up the calculation of global error probabilities in parallel sensor networks, which otherwise requires exponentially many computations in general. The motivation behind proposing such a fusion rule is to inform the other researchers that the recently available performance bounds are not tight as claimed and can only be used for very limited decentralized detection problems. The proposed fusion rule can be computed in quasi-linear time for identically and quasi-quadratic time for non-identically distributed independent sensor observations. Effectiveness of the proposed fusion rule is illustrated with comparative experiments for identical and non-identical sensors over varying size of networks and various quantization levels. |
8,399 | Please write an abstract with title: Stable teleoperation with time-domain passivity control, and key words: Time domain analysis, Control systems, Nonlinear dynamical systems, Nonlinear control systems, Delay, Damping, Stability analysis, System testing, Master-slave, Vibration control. Abstract: A new bilateral control scheme is proposed to ensure stable teleoperation under a wide variety of environments and operating speeds. System stability is analyzed in terms of the time-domain definition of passivity. A previously proposed energy-based method is extended to a 2-port network, and the issues in implementing the "passivity observer" and "passivity controller" to teleoperation systems are studied. The method is tested with our two-degrees-of-freedom master/slave teleoperation system. Stable teleoperation is achieved under conditions such as hard wall contact (stiffness >150 kN/m) and hard surface following. |
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