ID int64 0 400k | content stringlengths 97 5.85k |
|---|---|
13,900 | Please write an abstract with title: Heterogeneous Parallel Critical Nodes Detection, and key words: Social networking (online), Pandemics, Graphics processing units, Planning, Task analysis, Optimization, Information systems. Abstract: The Critical Node Detection Problem (CNDP) is a popular NP-complete graph-theoretical optimization problem with many real-world applications such as influencers in a social network, spreading of pandemics, project critical tasks as well as military strategy planning among many others. Past efforts to solve CNDP problems used heuristics solution with some vendor specific parallel GPU attempts that do not scale well on a heterogeneous system with a combination of CPU and GPU cores. In this paper, we propose and experimentally evaluate a novel heterogeneous algorithm for CNDP that significantly outperforms the earlier best known GPU specific parallel implementation by 2X in the context of real-world Twitter data. |
13,901 | Please write an abstract with title: Nitriding of Mechanically Pre-Activated Ferrochromaluminium in the Combustion Mode, and key words: Radiation effects, Powders, Combustion. Abstract: Nitriding of complex ferroalloy (ferrochromaluminium) by the method of self-propagating high-temperature synthesis with mechanical pre-activation of initial ferroalloy powder is presented in the paper. The combustion behavior of activated ferroalloy powder are revealed, the limits of the combustion of ferrochromaluminium powder are determined, and the combustion behavior and limits of the combustion reaction of unactivated and mechanically pre-activated ferroalloy powders are compared. |
13,902 | Please write an abstract with title: Robust Detection of Vowel Onset and End Points, and key words: Mel frequency cepstral coefficient, Lattices, Feature extraction, Error analysis. Abstract: A novel approach for detecting vowels, vowel onset-points and vowel end-points is presented in this paper. This study is motivated by the fact that some vowels have significant amount of spectral information even in the high frequency region. Furthermore, high-pitched speakers such as adult females and children have relatively more high frequency components than adult males. In order to effectively capture that information, we have exploited linear frequency cepstral coefficients (LFCC) along with Mel-frequency cepstral coefficients (MFCC). The MFCC features are known to down-sample the high frequency components. The LFCC features, on the other hand, provide equal resolution to all frequencies. Therefore, the use of LFCC features helps in effectively resolving high frequency components as well. In order to detect the vowels, two separate vowel non-vowel classification systems, employing deep learning architectures, are developed using MFCC and LFCC features, respectively. Next, for any given test utterance, lattices are generated using the trained acoustic models. The beginning time, duration and confidence scores are then extracted for each occurrence of vowel/non-vowel from the lattices. The weak evidences are discarded by applying a threshold on the confidence scores in order to reduce spurious detection. Finally, the evidences obtained using MFCC and LFCC features are weighted with their respective confidence scores and combined. The proposed approach is observed to outperform the existing ones. Using the detected vowel regions, we have also developed a simple scheme to determine whether the given speech utterance is from an adult or a child speaker. The developed scheme is highly effective in discriminating between adult and child speakers. |
13,903 | Please write an abstract with title: DSP Enabled, Amplitude Modulation Pilot Tone Based Optical Performance Monitoring in Coherent Systems, and key words: Optical filters, Optical fibers, Filtering, Optical fiber networks, Fiber nonlinear optics, Amplitude modulation, Transceivers. Abstract: We review the progresses of amplitude modulation pilot tone generation and detection techniques and its applications in optical performance monitoring, such as signal spectrum, optical filtering, and fiber nonlinearity. |
13,904 | Please write an abstract with title: Design Research of Physical Virtual Experiment Based on Virtual Reality Technology, and key words: Virtual reality, Solid modeling, Education, Physics, Instruments, Smart phones, Information technology. Abstract: The advent of the information age has brought rapid development and progress to all walks of life in society. In this trend, information technology has gradually integrated into the education industry, and combined with various disciplines has brought a qualitative leap to education. Educational researchers and front-line teachers are currently paying attention to research topics. The physics experiment in the physics course is an important part of students' physics learning. However, in actual teaching, many middle schools have poor teaching effects due to limited experimental conditions and cannot meet the learning needs of each student. Virtual reality VR technology, as a technology with a wide imagination space function, can construct and produce physical phenomena that are difficult to observe in reality. This article attempts to design virtual reality (VR) technology for the application of physics experiments, and hopes to explore the value of virtual reality technology in physics experiment teaching. |
13,905 | Please write an abstract with title: Attribute Assailability and Sensitive Attribute Frequency based Data Generalization Algorithm for Privacy Preservation, and key words: Data privacy, Publishing, Simulation, Forensics, Cluster computing, Big Data, Privacy breach. Abstract: The data publishing and analysis expose users’ and users group’s sensitive data and their identities. As a result, the adversary initiate inference attack using exposed users’ identifies and associated sensitive information. Some of the users’ attribute and users’ group attributes values are highly vulnerable and their contiguity increase privacy breach. The traditional k-anonymity based privacy models prevent identity disclosure but fails to prevent sensitive attribute values disclosure and ignore repercussion of assailable attributes on users’ group privacy. This research propose a novel data generalization algorithm that enhances users’ group privacy and data utility. The proposed method calculate the susceptibility of quasi-identifier attributes, frequency of sensitive attributes and their association. These values are used for form equivalence class that satisfies k-anonymity and β-likeness property. The proposed generalization algorithm considers both susceptibility, frequency of sensitive attributes and their association while anonymizing data. The extensive experiments are carried out on open source Apache Spark environment. The simulation results demonstrate that efficiency and effectiveness of proposed algorithm. This research work outperform other state-art data privacy model in terms of thwarting inference attack, information loss and accuracy of model. |
13,906 | Please write an abstract with title: MOS Devices and Integrated Circuits for Ionizing Radiation Dosimetry: a Review, and key words: Integrated circuits, Performance evaluation, Temperature dependence, Radiation effects, Ionizing radiation, Estimation, Detectors. Abstract: In this paper we review the main aspects of MOS dosimetry. MOS dosimeters have been used for the last 50 years, and its performance has improved since then. To understand how a MOS dosimeter works its limitations and the different strategies to overcome them, it is important to overview the radiation effects in the MOS structure and how it can be used for dose estimation. Different reading methods are presented that improve some aspects of the performance of the MOS dosimeter, such as its lifespan or the temperature dependence of the dosimetric signal. Different well established MOS devices used for dosimetry are reviewed, pointing out its advantages and disadvantages. We finish with the description of some integrated circuits specially designed with the aim of outperform those MOS devices and incorporate more functionality to the dosimeter. |
13,907 | Please write an abstract with title: SEMG classification for upper-limb prosthesis control using higher order statistics, and key words: Prosthetics, Higher order statistics, Elbow, Wrist, Pattern recognition, Pattern classification, Biomedical engineering, Muscles, Feature extraction, Motion detection. Abstract: The aim of this paper is to present application of higher order statistics for surface electromyogram (sEMG) signal pattern classification. The new pattern recognition algorithm exploits a multilayer perceptron (MLP) as the classifier and the feature vector is a combination of cumulants of the second-, third- and fourth- orders and integral of absolute (IAV) of two channel sEMG stationary segments. The detected sEMG signals are used in classifying four upper-limb primitive motions, namely, elbow flexion (F), elbow extension (E), wrist supination (S) and wrist pronation (P). The simulation results illustrate the considerable accuracy of the proposed framework in sEMG pattern recognition. |
13,908 | Please write an abstract with title: Medical image registration using mutual information, and key words: Biomedical imaging, Image registration, Mutual information, Medical diagnostic imaging, Image analysis, Magnetic resonance imaging, Computed tomography, Positron emission tomography, Digital images, Layout. Abstract: Analysis of multispectral or multitemporal images requires proper geometric alignment of the images to compare corresponding regions in each image volume. Retrospective three-dimensional alignment or registration of multimodal medical images based on features intrinsic to the image data itself is complicated by their different photometric properties, by the complexity of the anatomical objects in the scene and by the large variety of clinical applications in which registration is involved. While the accuracy of registration approaches based on matching of anatomical landmarks or object surfaces suffers from segmentation errors, voxel-based approaches consider all voxels in the image without the need for segmentation. The recent introduction of the criterion of maximization of mutual information, a basic concept from information theory, has proven to be a breakthrough in the field. While solutions for intrapatient affine registration based on this concept are already commercially available, current research in the field focuses on interpatient nonrigid matching. |
13,909 | Please write an abstract with title: Layered Coordination Architecture for Resilient Restoration of Power Distribution Systems, and key words: Switches, Control systems, Decision making, Computer architecture, Resilience, Power distribution, Load flow. Abstract: The current practices for restoring critical services in the distribution system during a disaster, align with the traditional centralized ideology of distribution systems operations. A central processor evaluates the distribution system after a disruption and attains a restoration plan. However, the centralized operational paradigm is susceptible to single-point failures, requires full situational awareness of the distribution system, and poses scalability challenges for large multifeeder distribution systems. This motivates a distributed decision-making paradigm where multiple agents solve smaller subproblems and jointly coordinate their individual decisions to achieve the global/network-level objective. Toward this goal, we propose a layered architecture for distributed algorithms for resilience and a two-stage distributed algorithm for distribution system restoration. The proposed distributed decision-making framework enables the bottom-up restoration of the distribution system using all available resources, including distributed generation, while only requiring local awareness and limited communications with neighboring connected regions. The proposed framework is robust to single-point failures, enables autonomy using distributed algorithms, and had reduced computational cost compared to centralized optimization solutions. |
13,910 | Please write an abstract with title: Study on the Oscillation Center of DFIG-based Wind Farm Power System, and key words: Reactive power, Analytical models, Power system dynamics, Doubly fed induction generators, Power system stability, Wind farms, Stability analysis. Abstract: Due to the characteristics of randomness, volatility and low inertia, the large-scale integration of new energy units has changed the original power flow distribution and deteriorated the transient stability of the system, resulting in the migration of the system oscillation center, which can even affect the accurate action of the splitting control. Aiming at the problem that the integration of doubly-fed induction generator (DFIG) affects the migration law of the oscillation center, firstly the Thevenin equivalent model of DFIG is constructed and the operating characteristics are analyzed. And then the equivalent admittance model of DFIG is constructed. Finally, based on the equivalent admittance model, the migration law of the oscillation center in the DFIG-based wind power system is analyzed. The results show that the out-of-step center (OOSC) moves away from the DFIG-based wind farm integration point when DFIG generates reactive power and moves close to the integration point when DFIG absorbs reactive power. While the migration range of the oscillation center extends to the entire line. |
13,911 | Please write an abstract with title: One solution for integrating graphics in vehicle digital cockpit, and key words: Graphics, Measurement, Virtual machine monitors, Operating systems, Switches, Real-time systems, Safety. Abstract: The accelerated development of the automotive industry and the impact of consumer technologies has contributed that many car manufacturers are switching from analogue to digital cockpits. Cockpits nowadays consist of a safety critical and a non-critical parts. The critical part of the system is the one that is necessary for safe driving, while the non-critical part of the system represents additional functionalities that make driving easier and more comfortable, but without them safe driving is possible. Each part of the system is displayed on a separate screen in a specific part of the cockpit. There are usually three displays - Central Information Display (CID) that represents non-critical part of the system, digital control panel - Cluster and Head-up display (HUD) that represent critical part of the system. These displays are controlled by two operating systems, which are connected by the hypervisor. A hypervisor is a concept that enables two operating systems to run simultaneously on one SoC in real- time. When critical and non-critical parts of a system are connected, it brings many safety issues. One of the problems is that sometimes information that is not necessary for safe driving, such as: information about an incoming call, the current song being played, is displayed on the Cluster. Displaying this information can affect the safety of Cluster operations. Therefore, it is necessary to somehow separate processing and displaying important from less important information for safe driving. In this paper we present one solution for displaying the maps information from the non- critical part of the system, on screen layer above Cluster that represents safety-critical part of the system. |
13,912 | Please write an abstract with title: Evaluation and Comparison of Different Motion Models for Flight Navigation, and key words: Adaptation models, Global navigation satellite system, Atmospheric modeling, Computational modeling, Motion segmentation, Dynamics, Estimation. Abstract: Navigation performance of a flight has to be maintained with a certain level of accuracy in civilian or military operations. Global navigation satellite system (GNSS) based devices in flights act as primary source of navigation. In order to improve the accuracy and robustness of the navigation, information from other systems (e.g. IMU) are fused together. The accuracy is further enhanced when adequate motion models are used during the estimation process. In this paper, we present results of multiple motion models in association with aircraft navigation and evaluate their performances. GNSS and inertial measurement unit (IMU) data are recorded in an aerial flight for about three hours. In order to highlight the impact of different motion models, data captured is processed post flight and position estimates are computed with a linearized Kalman filter (LKF). The computed positions are then compared with a reference trajectory and errors are evaluated for all the motion models. For different flight segments, the estimated position root mean square error (RMSE) varies up to a maximum of about 4 decimeters with different motion models. Also, the magnitude of the maximum deviations in highly dynamic maneuvers is reduced by a large extent when compared with different motion models and performance improvement is about 72%. |
13,913 | Please write an abstract with title: AutoRelax: HW-SW Co-Optimization for Efficient SpGEMM Operations With Automated Relaxation in Deep Learning, and key words: Sparse matrices, Hardware, Computational modeling, Data models, Deep learning, Indexes, Training. Abstract: We propose a HW-SW co-optimization technique to perform energy-efficient spGEMM operations for deep learning. First, we present an automated pruning algorithm, named AutoRelax, that allows some level of relaxation to achieve higher compression ratio. As the benefit of the proposed pruning algorithm may be limited by the sparsity level of a given weight matrix, we present additional steps to further improve its efficiency. Along with the software approach, we also present a hardware architecture for processing sparse GEMM operations to maximize the benefit of the proposed pruning algorithm and sparse matrix format. To validate the efficiency of our co-optimization methodology, we evaluated the proposed method on three benchmarks, language modeling, speech recognition and image classification. As a result, our approach improves the on-chip performance on spGEMM operations by 9.50$\sim$27.57% and achieves 15.35$\sim$33.28% energy reduction considering DRAM accesses over other sparse accelerators. |
13,914 | Please write an abstract with title: Can Consumer Electronics Be Truly Open?, and key words: Open source software, Consumer electronics, Business, Operating systems. Abstract: Today, the benefits of open-source (OS) software are clearly established, and many modern software systems build on it. Similarly, the OS movement is also experiencing great advances in areas other than software. This is particularly true in the consumer electronics (CE) domain, where an increasingly growing number of systems are based not only on OS software (OSS), but also on OS hardware (OSH) and OS networking (OSN). This column discusses to what extent it is possible to develop fully OS CE, now or in the near future. The main past and present contributions of OSH and OSN and their relationship with OSS initiatives are reviewed, and the main challenges and opportunities opened up in the context of OS CE are discussed. |
13,915 | Please write an abstract with title: Enabling transmission at 160 Gbit/s, and key words: Optical pulse generation, Optical attenuators, Optical receivers, Optical fiber polarization, Optical transmitters, Fiber nonlinear optics, Optical pulse compression, Pulse width modulation, Nonlinear optics, Optical signal processing. Abstract: We discussed optical signal processing for the next generation time division multiplexed (TDM) bit rate of 160 Gbit/s. First field trials show that this technique has a promising potential for practical applications. |
13,916 | Please write an abstract with title: Chromatic dispersion of thin film filters, and key words: Chromatic dispersion, Transistors, Optical filters, Optical films, Delay, Optical fiber filters, IIR filters, Band pass filters, Optical fiber networks, Dielectric thin films. Abstract: This paper discusses the chromatic dispersion effects of thin film filters used in telecommunications systems. ITU channel, banded architecture, and low dispersion filter results are presented. Design techniques to improve and manage chromatic dispersion in practical network implementations are discussed. |
13,917 | Please write an abstract with title: Synchronous and Channel-Sense Asynchronous Dynamic Group-Random-Access Schemes for Multiple-Access Communications, and key words: Delay, Communication channels, Communication system control, Application software, Radio network, Local area networks, Satellite communication, Computer networks, Distributed computing, Communication networks. Abstract: Adaptive random-access schemes are introduced and analyzed to provide access-control supervision for a multiple-access communication channel. The dynamic group-random-access (DGRA) schemes introduced in this paper implement an adaptive GRA structure. An active terminal transmits its ready packet at random within the next specified time period. Colliding packets are retransmitted at a random slot within the next time period. The duration of each time period is dynamically determined in accordance with the observed state of the channel during the previous time period. Synchronous and carrier-sense asynchronous DGRA procedures, the latter employing collision detection and/or idle detection, are considered. The schemes are shown to exhibit good delay-throughput characteristics. The carrier-sense ADGRA/ID scheme, employing idle detection, is shown to yield superior performance to that exhibited by other carrier-sense schemes, over a wide range of operational parameters. |
13,918 | Please write an abstract with title: Preventing substation tripping, and key words: Substations, Personal communication networks, Relays, Switching circuits, Computer aided software engineering, History, Current transformers, Wiring, Inspection, Switchgear. Abstract: This article describes an actual case history of substation nuisance tripping caused by a transformer differential relay due to rolled-out current-transformer (CT) connections. One set of differential relay CTs was installed averse order, and it's wiring was installed as if the CTs were stalled in the correct order. It was after several weeks of substation initial energization, when all plant auxiliary loads, such as lighting and small 480-V equipment, were in operation, the substation main transformer tripped on a line-to-ground arcing fault on the 480 V-system. Transformer differential relay settings, which caused tripping of the transformer for this through fault, were suspected to be in error. It was thought that perhaps arcing ground fault on the 480-V system contained a relatively higher magnitude of harmonic currents. Relay-setting calculations, especially the harmonic restraint, percent slope, tap ratio adjustment, and percent mismatch were reviewed and found to be within acceptable ranges. After thorough checking of relay settings and visual inspection of the substation transformer and switchgear, the field crew reenergized the substation while the technical investigation by the author was still in progress. |
13,919 | Please write an abstract with title: Short-tenn spectrl stabilit of super-continuum source using noise-like pulses generated from an EDF laser, and key words: Laser stability, Optical pulse generation, Noise generators, Laser noise, Fiber lasers, Laser modes, Optical devices, Laser theory, Optical noise, Optical fiber testing. Abstract: We experimentally investigate shot-term spectral stability of supercontinuum sources. We show that a supercontinuum source using noise-like pulses generated from an EDF fiber laser achieves excellent stability within plusmn0.05dB in the almost entire wavelength range |
13,920 | Please write an abstract with title: Privacy-Preserving Fast Three-Factor Authentication and Key Agreement for IoT-Based E-Health Systems, and key words: Authentication, Biometrics (access control), Security, Passwords, Medical services, Cryptography, Smart cards. Abstract: Electronic healthcare (e-health) systems have received renewed interest, particularly in the current COVID-19 pandemic (e.g., lockdowns and changes in hospital policies due to the pandemic). However, ensuring security of both data-at-rest and data-in-transit remains challenging to achieve, particularly since data is collected and sent from less insecure devices (e.g., patients’ wearable or home devices). While there have been a number of authentication schemes, such as those based on three-factor authentication, to provide authentication and privacy protection, a number of limitations associated with these schemes remain (e.g., (in)security or computationally expensive). In this study, we present a privacy-preserving three-factor authenticated key agreement scheme that is sufficiently lightweight for resource-constrained e-health systems. The proposed scheme enables both mutual authentication and session key negotiation in addition to privacy protection, with minimal computational cost. The security of the proposed scheme is demonstrated in the Real-or-Random model. Experiments using Raspberry Pi show that the proposed scheme achieves reduced computational cost (of up to 89.9% in comparison to three other related schemes). |
13,921 | Please write an abstract with title: AC discharge performance of short ball-ball and rod-plate air gaps under water mist conditions, and key words: Electric breakdown, Electrodes, Fires, Water, Air gaps, Power transformer insulation, Measurement by laser beam. Abstract: This study explores the influence of water mist droplet diameter and the spacing between the droplets on the alternating current breakdown characteristics of a water mist-air mixture (WAM) between short ball-ball and rod-plate gaps. The experimental results show that the diameter of the water mist droplets and the electrode structure influence the breakdown while the spacing between the water droplets shows a slight affect. Computations are carried out on various droplet sizes and spacings between the droplets between ball-ball and rod-plate electrodes and it is observed that the maximum electric field in the gap increases with increasing diameter of the water mist droplets. Comparatively, the spacing between the droplets of water mist shows a small influence on the electrostatic field distortion in the gaps. In addition, the effect of water mist droplets on the electrostatic field of the ball-ball electrodes is greater than that of the rod-plate electrodes. |
13,922 | Please write an abstract with title: A Learning Analytics Dashboard for Moodle: Implementing Machine Learning Techniques to Early Detect Students at Risk of Failure, and key words: Learning management systems, Machine learning, Data mining. Abstract: Learning Analytics Dashboards are important tools that help professors to follow and understand students behavior inside Learning Management Systems. Moodle is one of the most popular and used Learning Management Systems available nowadays, and a number of initiatives have been conducted to offer Learning Analytics features inside it. The present paper describes MAD2, a Learning Analytics Dashboard developed for Moodle that offers different visualizations about students interactions inside the environment, and that uses machine learning techniques to early predict students at-risk of failure. The paper describes the predictive approach implemented inside the tool together with the most important visualization features available to the users. The offering of a tool to early predict students at-risk of failure inside Moodle is an important step to help professors and managers to better assist students during their courses. |
13,923 | Please write an abstract with title: Target Architecture of Distribution Network Monitoring System towards Energy Revolution and Digitization, and key words: Distribution networks, Computer architecture, Market research, Electric vehicle charging, Monitoring, Optimization, Load flow. Abstract: In order to adapt to the energy revolution and digitization, a new design for the distribution network monitoring system is proposed to achieve data lifecycle management. Firstly, the current practices and limitations of existing monitoring systems are presented. According to the development trend, the reconstruction strategy is presented involving three feedback local-computing loops and data interaction between distributed intelligent agents and cloud-based master station. To support the huge scale of sensed data integration and transmission, the reference framework of data interaction is established, and the main monitoring information is presented. Then some technical evolution trends towards the new architecture are described in the fields of unified model, new generation of intelligent terminal, network interconnection, edge-cloud computing and security system. |
13,924 | Please write an abstract with title: Ocean science concept mapping: what do people need to know about ocean sciences, and key words: Oceans, Geoscience, Humans, Educational programs, Collaborative work, Councils, Guidelines, Impedance, Standards development, Marine technology. Abstract: While attempting to infuse more ocean science research into K-16 classrooms, museums and aquaria, the New England Regional Center for Ocean Sciences Education Excellence (NER-COSEE) is focused on identifying excellent examples of ocean science education. However, without a "map" of ocean sciences, it is difficult or impossible to meet the needs of both the research and education communities. Therefore, we are using a combination of surveys, small working groups, concept mapping strategies, and collaboration across the ocean science community to produce a simplified web of age appropriate ocean science concepts along with excellent examples of how to teach these concepts. |
13,925 | Please write an abstract with title: Programmable Shape Morphing of Rose Mechanical Metamaterials, and key words: Electric potential, Shape, Loading, Three-dimensional printing, Metamaterials, Behavioral sciences, Smart devices. Abstract: Auxetic and conventional mechanical materials can be combined to program the shape morphing behavior of structures. We proposed a configuration of mechanical metamaterial unit cells shaped like four-leaved rose curves. These rose unit cells can have a wide range of positive and negative Poisson's ratios governed by a single control parameter. With the rose unit cells, we implemented a programmable design of structural deformation under loading. Two geometric parameters are engaged to optimize the shape morphing effect. We fabricated several programmable metamaterial samples by SLA 3D printing, performed tensile loading tests, and got a good agreement between the numerical and experimental results. |
13,926 | Please write an abstract with title: A Reputation-Based Mechanism for Transaction Processing in Blockchain Systems, and key words: Blockchains, Costs, Peer-to-peer computing, Generators, Bitcoin, Denial-of-service attack, Delays. Abstract: Blockchain protocols require nodes to verify all received transactions before forwarding them. However, massive spam transactions cause the participants in blockchain systems to consume many resources in verifying and propagating transactions. This paper proposes a reputation-based mechanism to increase the efficiency of processing transactions by considering the reputations of the sending nodes. Reputations are in turn adjusted based on the quality of transaction processing. Our proposed reputation-based mechanism offers three main contributions. First, we modify the verification strategy so that nodes set a probability of verifying a received transaction considering the likelihood of it being spam: transactions from a node with a low reputation have a high probability of being verified. Second, we optimize the transaction forwarding protocol to reduce propagation delay by prioritizing forwarding transactions to reputable receivers. Third, we design a data request protocol that provides alternative data exchange methods for nodes with different reputations. A series of simulations demonstrate the performance of our reputation-based mechanism. |
13,927 | Please write an abstract with title: A proposal of a multi-agent supporting system for network community formation, and key words: Proposals, Information technology, Computer networks, Systems engineering and theory, Technological innovation, IP networks, Delay, Joining processes, Particle measurements, Telecommunication traffic. Abstract: Information-oriented network society is advancing far beyond our speculation based on the rapid innovations of information and network technologies. Large amount of people become suffering from so-called information barrier When we consider people with informational handicaps, a large gap is opening up between those who can use computers effectively to process information and those who cannot. People interact in the network society through network communities and one of the major issues in the network society is how to bring people together, that is how to form the communities that share similar interests. Active usage of information with the help of personal agents that interact with each other, gather information, and assist the user seems inevitable. Although, users interact through explicit communities, it is more natural and with fewer barriers to form communities as implicit communities using user's profiles and then to introduce users to explicit communities. In this paper, we propose a multi-agent supporting system for implicit community formation and discuss methods to encourage effective information exchanges between community members and to improve the quality of their lives. |
13,928 | Please write an abstract with title: Distributed Data Recovery Against False Data Injection Attacks in DC Microgrids, and key words: Voltage fluctuations, Fluctuations, Distributed databases, Microgrids, Maintenance engineering, Information filters, Information and communication technology. Abstract: With the development of information and communications technology (ICT) in DC microgrids (DCmGs), the threat of false data injection attacks (FDIAs) is becoming more and more serious. However, the existing literature mainly focuses on the detection and identification of FDIAs in DCmGs, while the data recovery after the perception of FDIAs has never been thor-oughly investigated yet. In this paper, we propose a distributed data recovery scheme to eliminate the adverse impact caused by FDIAs in DCmGs. Firstly, by observing the point of common coupling (PCC) voltage under FDIAs, the injected constant bias can be roughly estimated. In order to obtain the precise constant bias, the mean filter (MF) is adopted to handle the measurement noises and small oscillations. Then, the estimated precise constant bias is compensated for the communicated signal to eliminate the attack impact. Furthermore, our proposed data recovery scheme, which only needs local information, is fully distributed. Finally, the accuracy and effectiveness of the distributed data recovery scheme are evaluated through systematical hardware-in-the-loop (HIL) experiments. |
13,929 | Please write an abstract with title: Investigation on Utilization of thin SOI layer as resistor in SOTB process, and key words: Resistors, Temperature, Process control, Analog circuits, Conductivity, Silicon, Temperature control. Abstract: A thin SOI layer in the Silicon on thin BOX (SOTB) process is utilized as a resistor. it revealed that good mismatch characteristics or temperature coefficient of resistivity (TCR) can be obtained by controlling the crystallinity of the SOI layer and will be used effectively in an analog circuit. |
13,930 | Please write an abstract with title: RL-Based Interference Mitigation in Uncoordinated Networks with Partially Overlapping Tones, and key words: Signal processing algorithms, Interference, Time-frequency analysis, Signal to noise ratio, Dispersion, Wireless communication, Prototypes. Abstract: Partially-overlapping tones (POT) are known to help mitigate co-channel interference in uncoordinated multi-carrier networks by introducing intentional frequency offsets (FOs) to the transmitted signals. In this paper, we explore the use of POT with reinforcement learning (RL) in dense networks where multiple links access time-frequency resources simultaneously. We propose a novel framework based on Q-learning, to obtain the FO for the multi-carrier waveform used for each link. In particular, we consider filtered multi-tone (FMT) systems that utilize Gaussian, root-raised-cosine (RRC), and isotropic orthogonal transform algorithm (IOTA) based prototype filters. Our simulation results show that the proposed scheme enhances the capacity of the links by at least 30% in additive white Gaussian noise (AWGN) channel at high signal-to-noise ratio (SNR), and even more so in the presence of severe multi-path fading. For a wide range of interfering link densities, we demonstrate substantial improvements in the outage probability and multi-user efficiency facilitated by POT, with the Gaussian filter outperforming the other two filters. |
13,931 | Please write an abstract with title: Robust Data Association for Multi-Object Detection in Maritime Environments Using Camera and Radar Measurements, and key words: Cameras, Radar, Radar imaging, Marine vehicles, Feature extraction, Radar detection, Radar measurements. Abstract: This letter presents a robust data association method for fusing camera and marine radar measurements in order to automatically detect surface ships and determine their locations with respect to the observing ship. In the preprocessing step for sensor fusion, convolutional neural networks are used to perform feature extraction from camera images and semantic segmentation from radar images. The correspondences between the camera and radar image features are optimized using a pair of geometric parameters, and the positions of all the matched object features are determined. The proposed method enables robust data association even without accurate calibration and alignment between the camera and radar measurements. The feasibility and performance of the proposed method are demonstrated using an experimental dataset obtained in a real coastal environment. |
13,932 | Please write an abstract with title: Electromagnetic Characterization of the Tommy Atkins Mango in the Maturation Period, and key words: Dielectric measurement, Dielectric constant, Dielectric losses, Frequency measurement, Dielectric loss measurement, Permittivity, Loss measurement. Abstract: This work presents the characterization of the dielectric properties (dielectric constant and loss factor) of the Tommy Atkins mango (Mangifera indica L), which is a fruit of great economic importance for Brazil. For the characterization, the coaxial probe method was used for frequencies between 1 and 5 GHz. The Vector Network Analyzer 16451B and the software Dielectric Probe 85070 manufactured by Agilent were used. Measurements were performed on the outer part of the fruit, on the shell and also on the inside, relating the results to the maturation index of the mango, identified by the yellowish tone in its shell, as well as the amount of soluble solids (amount of sugar). The results allowed to correlate the dielectric characteristics of the fruit with the physical-chemical transformations that occurred in the maturation process of the mango, as well as the sugar content. The lowest value was determined for the dielectric constant and for the tangent of losses on the day of the fruit's peak maturity. The results show that it is possible to identify the properties of the mango studied through non-invasive measures on the fruit peel. |
13,933 | Please write an abstract with title: Construction of Continuous and Piecewise Affine Feedback Stabilizers for Nonlinear Systems, and key words: Lyapunov methods, Nonlinear systems, Stability criteria, Closed loop systems, Interpolation. Abstract: In this article, two methods for constructing continuous and piecewise affine (CPA) feedback stabilizers for nonlinear systems are presented. First, a construction based on a piecewise affine interpolation of Sontag's “universal” formula is developed. Stability of the corresponding closed-loop system is verified a posteriori by means of a CPA control Lyapunov function and subsequently solving a feasibility problem. Second, we develop a procedure for computing CPA feedback stabilizers via linear programming, which allows for the optimization of a control-oriented criterion in the synthesis procedure. Stability conditions are a priori specified in the linear program, which removes the necessity for a posteriori verification of closed-loop stability. We illustrate the developed methods via two application-inspired examples considering the stabilization of an inverted pendulum and the stabilization of a healthy equilibrium of the hypothalamic-pituitary-adrenal axis. |
13,934 | Please write an abstract with title: Prediction of the Target User Segment for Paid Advertisement, and key words: Measurement, Databases, Clustering algorithms, Predictive models, Prediction algorithms, Spatial databases, Classification algorithms. Abstract: The primary objective of this work is to develop a methodology for identification of a segment of customers to whom advertisement(s) of a particular product can be shown. One of the important aspects of this work is data. To create a database of the customer, datasets from different sources/websites are collected, cleaned and preprocessed to prepare the customer database. DBSCAN (Density-based spatial clustering of applications with noise) clustering algorithm is then used to form customer segments. KNN (k-Nearest Neighbour) algorithm and performance metrics like Silhouette Coefficient are used for the smooth conduct and working of the clustering algorithm. The customer database and the labels generated after clustering are used to build and train a Logistic Regression classification Model. For identifying the customer segment for a particular product, the characteristics of a product are converted into a database by doing a Cartesian product. The classification model is then used to predict the classes/labels for the product. The labels predicted by the Classification Model are used to extract a target customer segment(s). |
13,935 | Please write an abstract with title: Analysis of Residential Consumers’ Attitudes Toward Electricity Tariff and Preferences for Time-of-Use Tariff in Korea, and key words: Tariffs, Mathematical models, Analytical models, Vehicle dynamics, MIMICs, Random variables, Pricing. Abstract: In recent years, a Time-of-Use (TOU) tariff for residential consumers has received much more attention with the increasing deployment of smart meters for residential consumers in Korea. The introduction of the TOU tariff for residential consumers is expected to allow residential consumers to have a choice of electricity rate plans in addition to load management. An analysis of residential consumers’ preferences for the TOU tariff is needed to identify TOU attributes’ levels. This paper analyzes Korean consumers’ attitudes toward current residential electricity tariff and preferences for TOU tariff using demographic characteristics collected by a face-to-face survey. Consumers’ preferences on key attributes of TOU tariff are analyzed using the conjoint analysis, and attitudes toward current residential electricity tariff are estimated by the multiple indicators multiple causes (MIMIC) model. The analysis results of this study show that based on their attitude toward electricity tariff, consumers’ attitudes can be divided into three latent variables, and preferences for TOU tariff are discrete by group rather than continuous by individual consumer. |
13,936 | Please write an abstract with title: Sustainable Leadership in a Post Pandemic HE World, and key words: Leadership, Philosophical considerations, Pandemics, Education, Curriculum development, Linguistics, Reflection. Abstract: This article describes the DREAM Educational Management and Leadership professional development programme delivered over the past two decades and the qualitative research analysis of teacher participant reflections that has continuously informed the refinement of the DREAM model and the programme’s structure and methodology.The first part of the article gives a brief overview of the 2007 DREAM Management and Leadership approach and the 12-module programme’s content and methodology with pre-session readings and viewings, weekly synchronous and asynchronous Discussions, applied tasks in the participant’s work context, and final module reflections, linking the approach to the seven principles of Sustainable Leadership [1].The second part of the article briefly describes three research projects undertaken over the past decade whilst delivering the professional development programme. The first of these research projects used categorization to determine whether the initial module structure could be mapped effectively to a model of teacher knowledge development that states teacher knowledge is developed through a cycle of four stages from Knowledge Seeker through Knowledge Discusser and Knowledge User to Knowledge Provider [2]. The research used these four categories and mapped them onto participant communications to determine whether the model could provide a sound theoretical structure for the delivery of the programme. The second research project used a lexical analysis of participant communication to further inform the tutor’s interaction with those taking the course. The research used eleven keys to effective web developer communication [3] as the linguistic markers for the segmentation of the data collected from participant email discussions to produce a set of clear guidelines for tutor communication on the programme. The third research project used Burton’s reflective typology [4], [5] to analyse participant reflections, and the outcome informed revisions to the reflective tasks and the ways in which the tutor should give feedback [6].The final part of the article concludes with an updated overview of the DREAM Educational Management and Teacher Leadership professional development programme as it will be delivered in 2021-2022, so the reader can appreciate the changes made based on the research. The author then argues for the value of research on our daily course delivery and ongoing curriculum development, and the importance for all teachers to view themselves as pedagogical researchers. Finally, the author concludes by stressing the need for structured professional development on teacher leadership that is grounded in on-going research throughout the higher education sector, so that educational leadership can be truly sustainable. |
13,937 | Please write an abstract with title: Development of the approach to collaborative BCI, and key words: Visualization, Electroencephalography, Brain-computer interfaces, Task analysis, Collaboration, Robots, Brain. Abstract: In the present study we aim to find specific characteristic based on brain activity, that can be used to evaluate attention and, thus, can be used in brain-computer interface. We propose an approach to collaborative BCI aimed to enhance human-to-human interaction while performing shared visual task. We also describe the setup for such BCI and its possible application in long task of classifying ambiguous visual stimuli with varying degrees of ambiguity by a group of people. |
13,938 | Please write an abstract with title: Quantifying the Severity of Loose Smut in Wheat Using MRCNN, and key words: Training, Neural networks, Software, Indexes, Convolutional neural networks, Viruses (medical), Diseases. Abstract: Wheat is one of the most common staple foods in the world. According to national agricultural research, an entire 40% of wheat grain quality has been decreased due to wheat diseases. The wheat disease mainly affects the wheat plant. Sometimes, the wheat disease damages the whole wheat plant. When the whole wheat plant is damaged, the quality of wheat grain is decreased. There are different varieties of wheat diseases such as fungal, bacterial, and virus-based diseases. One of the most common loose smut fungal diseases that decrease the grain quality in each wheat spikelet. Therefore, the identification of wheat diseases is important. In this paper, an automatic system for the identification of loose smut wheat disease along with its severity is proposed. The identification system uses 2000 RGB images which have been collected from secondary sources. Among all datasets, a total of 800, 700 images have been randomly selected for training and testing purposes in the Mask RCNN model. Through Labelme software, the images are labelled with ground and truth labels. During identification, our proposed system achieves a 97.8% F1 score for loose smut identification with bounding boxes. The severity of loose smut has been calculated through the disease severity index. With the help of DSI, a total of 63% severity for loose smut has been estimated in different wheat spikelets. |
13,939 | Please write an abstract with title: Motivation factors that make knowledge workers share their tacit knowledge in universities: an empirical research, and key words: Educational institutions, Technological innovation, Concrete, Knowledge management, Cost benefit analysis, Communications technology. Abstract: On the basis of reviewing on the existing literatures about knowledge sharing, this paper states that the tacit knowledge sharing among knowledge workers plays an important role in improving universities' competences. Through a KT model, the characteristics of different types of knowledge workers in universities are analyzed. And basing on an empirical research, motivation factors that make knowledge workers share their tacit knowledge in universities are obtained and it is also found that the importance of these motivators is dissimilar for different types of knowledge workers. Then a motivation model is presented suggesting more concrete and efficient motivation mechanisms for the tacit knowledge sharing in universities. |
13,940 | Please write an abstract with title: Analysis of the Shielding Effectiveness of Thin Wire Cages by a Hybrid DGTD-FDTD Method, and key words: Wires, Mathematical models, Time-domain analysis, Voltage, Finite difference methods, Junctions, Electron tubes. Abstract: Thin wire simulation is a typical multiscale problem in time-domain computational electromagnetic methods. This article addresses the shielding effectiveness of thin wire cages, and such models can be attributed to complex thin wire structures with multiwire junctions. The discontinuous Galerkin time-domain method for Maxwell's equations is used in our study, and the one-dimensional finite-difference time-domain method is used to construct the iterative scheme for the thin wire. The thin wire is expressed by the modified telegrapher's equations proposed by Holland. In this article, the mesh size is determined by the wavelength of the electromagnetic wave to be analyzed without considering the radius of the thin wire. There is no physical presence of thin wires in our model, and thin wires are expressed by current elements. The proposed method supports the simulation of arbitrarily oriented thin wires, and the proposed method can easily handle complex wire structures. The calculation efficiency can be greatly improved after avoiding multiscale modeling. |
13,941 | Please write an abstract with title: Autonomous Car Parking System using Deep Reinforcement Learning, and key words: Image sensors, Image segmentation, Visualization, Virtual environments, Reinforcement learning, Cameras, Turning. Abstract: In recent years, technologies based on deep learning have been useful in various aspects of our daily lives. In the field of automated driving, which is attracting particular attention, image recognition technology is used to detect roads, white lines, and vehicles ahead. However, since automated vehicles are controlled by acquiring information about the vehicle's position and surrounding environment mainly from image sensors and cameras, the production cost is very high. The goal of this research is to develop autonomous driving technology using only an on-board visual camera, without any image sensors. Automatic parking is implemented using reinforcement learning in the virtual environment of Unity. Autonomous parking with high accuracy is achieved by using the input image as a segmentation image. |
13,942 | Please write an abstract with title: Baseline results for the challenge problem of HumanID using gait analysis, and key words: Humans, Databases, Video sequences, Computer science, Computer vision, Footwear, Legged locomotion, Availability, NIST, Measurement standards. Abstract: Identification of people from gait captured on video has become a challenge problem in computer vision. However there is not a baseline algorithm or standard dataset for measuring, or determining what factors affect performance. In fact, the conditions under which the problem is "solvable" are not understood or characterized. This paper describes a large set of video sequences (about 300 GB of data related to 452 sequences from 74 subjects) acquired to investigate important dimensions of this problem, such as variations due to viewpoint, footwear, and walking surface. We introduce the HumanID challenge problem. The challenge problem contains a set of experiments of increasing difficulty, a baseline algorithm, and its performance on the challenge problem. Our results suggest that differences in footwear or walking surface type between the gallery and probe video sequence are factors that affect performance. The data set, the source code for the baseline algorithm, and UNIX scripts to reproduce the basic results reported are available to the research community at http://marathon.csee.usf.edu/GaitBaseline/. |
13,943 | Please write an abstract with title: Torque ripple minimization in direct torque control of induction machines, and key words: Torque control, Induction machines, Pulse width modulation inverters, Voltage, Stators, Equations, Induction motors, Fuzzy logic, Steady-state, Pulse width modulation. Abstract: A duty ratio control scheme for inverter-fed induction machines using the direct torque control (DTC) method is presented. An improved steady state torque response was achieved using the duty ratio control and had shown less torque ripple compared to the conventional DTC. Fuzzy logic control has been used to implement the duty ratio during each switching cycle using the torque and flux errors as inputs. Simulation results using SIMULINK gave results that justify the claims. |
13,944 | Please write an abstract with title: Mathematical Model Of Skin Epidermis Regulatory Mechanisms in Squamous Cell Cancers Development, and key words: Chaotic communication, Computational modeling, Epidermis, Regulation, Mathematical model, Tumors, Cancer. Abstract: The article is devoted to the study of the regulatory mechanisms dynamics of skin carcinoma on the basis of the firmly established facts and theoretical positions in the field of biology, biophysics and regulation. The developed equations for the regulatory mechanisms of skin cells transformation into abnormal cancer cells have a functional-differential type. Implementation of the developed equations for the epidermis cellular communities number regulation in squamous cell carcinoma on a computer and a series of computational experiments have shown that these equations have stable stationary, self-oscillating solutions typical for the normal functioning of the skin; have chaotic solutions and the “black hole” effect, which makes it possible to diagnose the onset of the phase of unpredictable changes in the skin epidermis regulation and the beginning of the transition into tumor cells. Mathematical and computer models of the skin epidermis regulation at the norm and at the tumor process can be used to improve the methods of early diagnosis, prevention of skin diseases, as well as to choose treatment tactics. |
13,945 | Please write an abstract with title: The Integrated Optic Spectrum Analyzer -- a First Demonstration, and key words: Integrated optics, Spectral analysis, Semiconductor laser arrays, Optical arrays, Radio frequency, Sensor arrays, Surface acoustic waves, Bandwidth, Optical surface waves, Charge coupled devices. Abstract: This paper reports on the performance of the first fully Integrated Optical Spectrum Analyzer consisting of a GaAlAs semiconductor laser, a LiNb0/sub 3/ integrated optic chip, and a Si detector/CCD linear array, |
13,946 | Please write an abstract with title: Fabrication of CaF/sub 2//Si/CaF/sub 2/ resonant-tunneling diodes by B-surfactant enhanced epitaxy of Si quantum-well layers, and key words: Fabrication, Semiconductor films, Resonant tunneling devices, Diodes, Boron, Epitaxial growth, Quantum wells, Substrates, Temperature, Amorphous materials. Abstract: Double-barrier CaF/sub 2//Si/CaF/sub 2/ resonant-tunneling diodes (RTDs) were fabricated by utilizing a new boron (B) surfactant-enhanced solid-phase epitaxy (SPE) technique for the critical growth of the Si quantum-well films on CaF/sub 2//Si(111) substrates. This technique consists of the room temperature deposition of an amorphous Si film, the subsequent deposition of one monolayer of B atoms, and annealing to about 635/spl deg/C. This resulted in continuous and smooth epitaxial Si layers on CaF/sub 2/ with a sharp B-induced (/spl radic/3/spl times//spl radic/3 )R30/spl deg/ surface reconstruction. At 77 K the RTDs exhibited stable N-type I-V characteristics with negative differential resistance (NDR) with 2-7 orders of magnitude higher peak currents and much lower peak voltages than in earlier results. |
13,947 | Please write an abstract with title: Sensor-based probabilistic roadmaps for car-like robots, and key words: Robot sensing systems, Motion planning, Process planning, Computer science, Navigation, Orbital robotics, Robot vision systems, Cameras, Mobile robots, System recovery. Abstract: This work deals with the sensor-based motion planning problem for car-like robots. Sensor-based versions of PRM and Lazy-PRM are used to exploit the information obtained from sensors and to compute a feasible collision-free path. The algorithm tries to reach the goal by executing the local method in the known free region. If it succeeds, a feasible path to the goal is found and the algorithm finishes. Otherwise, the algorithm executes more scans to extend its free space, and so on. Experimental results are promising. |
13,948 | Please write an abstract with title: Sensitivity Enhancement of An Acoustic Sensor via Parallel Helmholtz Resonators, and key words: Radio frequency, Micromechanical devices, Sensitivity, Conferences, Resonator filters, Resonant frequency, Receivers. Abstract: This paper reports an acoustic sensor using a Helmholtz resonator (HR) array and a MEMS differential pressure (DP) sensor element. A piezoresistive cantilever type DP sensor is highly sensitive to acoustic waves around its mechanical resonant frequency (RF). By attaching a HR array of which RF is equal to the cantilever in front of the DP sensor like a cap, the sensitivity is enhanced at the RF. The developed sensor with the HR responded with 3 times higher sensitivity than without the HR, and realized a resolution of approximately 2 mPa without an electrical lock-in filter. |
13,949 | Please write an abstract with title: Local Resistance Measurement for Degradation of c-Si Heterojunction with Intrinsic Thin Layer (HIT) Solar Modules, and key words: Resistance, Electrical resistance measurement, Probes, Degradation, Current measurement, Area measurement, Solar power generation. Abstract: Silicon heterojunction with intrinsic thin layer (or HIT) modules typically degrade at a rate of less than 1% annually in solar fields with dominant degradation in open-circuit voltage and some degradation in series resistance. However, detailed mechanisms can differ from module to module. Here, we study increases in local series resistance that occur over long-term field deployment, indicated by cell areas where the photoluminescence intensity does not degrade but the electroluminescence degrades significantly. To directly measure the local series resistance, we have cored out the local electroluminescence-degraded area, and we measured the sheet resistance by 4-point-probe and local nm-scale resistance using scanning spreading resistance microscopy (SSRM). The results by 4-point-probe show scattered sheet resistance that can be caused, for example, by nonuniform current paths through the transparent conductive oxide layer, the a-Si:H emitter, or the near-junction c-Si inversion layer. In contrast, the SSRM results indicate a relatively uniform and non-degraded resistivity on smaller nanometer spatial scales. SSRM is an atomic force microscopy-based two-terminal resistance mapping technique that measures the local resistance in nm-volume beneath the probe. The consistent resistances measured on the control and degraded samples can exclude the degradation of transparent conductive oxide resistance. |
13,950 | Please write an abstract with title: Using split objects for maintenance and reengineering tasks, and key words: Wrapping, Java, Logic, Software maintenance, Dynamic programming, Information systems, Application software, Software testing, Computer languages, Manipulator dynamics. Abstract: Language integration is an important issue in the area of software maintenance and reengineering. We describe a novel solution in this area: automatically applied and composed split objects. Split objects provide a language integration that goes beyond simple wrappers by integrating object identity, state, methods, and class hierarchies of entities in two languages to one logical entity. The split object concept can be applied as an aspect-oriented solution, in which an aspect of a system is implemented in another language. After describing these concepts and two split object frameworks that we have implemented, we discuss how split objects can be applied for other maintenance and reengineering tasks than language integration. These application fields include software component testing, dynamic feature analysis, and variation and configuration management. |
13,951 | Please write an abstract with title: Cancer Detection in Breast Histopathology with Convolution Neural Network Based Approach, and key words: Feature extraction, Breast cancer, Convolution, Image color analysis, Microscopy. Abstract: Breast cancer is one of most common causes of mortality in women. However, few limitations, e.g., similar structure statistics in inter-class and textural variations in intra-class images make the breast histology analysis a challenging process. In this paper, the multi-class breast cancer classification is carried out with deep convolution neural network (CNN) based transfer learning approach. To explore the feasibility of transfer learning in breast histology, pre-trained deep CNN model is inherited and simultaneously a multi-scale feature concatenation strategy is used. Moreover, incorporating with stain normalization and channel color modification strategies the designed model can be effectively trained. The experiments on publicly available multi-class ICIAR 2018 breast dataset corroborated the efficiency of ou method. The designed approach outperforms the existing methods by achieving 94.3% and 97.5% accuracy on 4-class and 2-class histology image recognition respectively. |
13,952 | Please write an abstract with title: Analysis on the Information Management of University Electronic document in the Big Data Era, and key words: Leadership, Education, Big Data, Internet, Information management, Complexity theory, Information technology. Abstract: At present, China is rapidly moving into the Era of Data and big data will gradually become a part of the infrastructure of modern society. Moreover, the leading position and digitization of electronic document is becoming the basic support for the development of document management in Universities. Affected by big data, the work mode of document management in colleges and universities has changed and document information is digitized. Through survey data analyzing and program designing, we can find out the status of University Digital document Management and the electronic document problems in the work, which can provide a realistic basis for the research and practice of electronic document in colleges and universities. |
13,953 | Please write an abstract with title: Rough set model in incomplete and fuzzy decision information system based on improved-tolerance relation, and key words: Fuzzy sets, Fuzzy systems, Information systems, Set theory, Management information systems, Fuzzy set theory, Uncertainty, Pattern recognition, Data mining, Data analysis. Abstract: The topical rough set theory is a forceful tool to handle the complete information system, and its effect to process incomplete information system is poor, particularly, its function to combine the incomplete information system with fuzzy decision information system is poorer. On the base of improving on the tolerance relation made by M. Kryszkiewez, this paper proposes the improved-tolerance relation and improved-tolerance classes; we simultaneously present the definition of the incomplete and fuzzy decision information system based on the improved-tolerance relation, and give its rough set model, i.e. the rough set model in incomplete and fuzzy decision information system. Finally, the conception of precision reduction is defined, and its algorithm is also supplied. |
13,954 | Please write an abstract with title: Integration of 980 nm AlGaAs/InGaAs laser diode and semiconductor optical amplifier, and key words: Indium gallium arsenide, Diode lasers, Semiconductor optical amplifiers, Semiconductor diodes, Light sources, Charge carrier processes, Optical noise, Optical amplifiers, Gallium arsenide, Radiative recombination. Abstract: In this paper a new concept of a light source integrated with semiconductor optical amplifier (SOA) is described. The device model and results of computer simulations are presented. Influence of the number of quantum wells (QW) in an active region on the device performance is discussed. |
13,955 | Please write an abstract with title: Hands-on Experiments in Electricity for Physics Teachers and Students, and key words: Electronic learning, Conferences, Engineering education, Electromagnetics, Physics. Abstract: This paper describes the technique and outcomes of a Massive Open Online Course lab on a series of electric experiments for primary school students, predominantly engaged physics teachers. This course will integrate simple electric and electronic experiments with fundamental physics concepts through simple hands-on experiments. The research concentrated on a teacher’s online physics lab that students in a classroom setting evaluated. The findings of both labs are assessed, and teachers’ and students’ comprehension of fundamental physics laws applied to simple electric circuits. By introducing students to experimental physics, the hands-on experiments encourage teachers to foster a research culture in their students. Our findings indicate a need for more emphasis on specific electrical and electromagnetic themes and research-based and research-validated educational materials. |
13,956 | Please write an abstract with title: Big Data Analytics in Education: A Data-Driven Literature Review, and key words: Analytical models, Solid modeling, Data privacy, Data analysis, Systematics, Bibliographies, Computational modeling. Abstract: In the past decade, the applications of big data and learning analytics in education have made significant headways resulting in new opportunities for educational research. However, big data analytics (BDA) has brought new challenges to educational analytics. This paper conducts a systematic data-driven Literature review of BDA in education. Using a topic modeling approach, we have identified six topics and 19 subtopics and performed a network analysis to explore the links between the topics. Based on the results, we investigate the challenges in the field and conclude a three-dimensional model for educational BDA to address these challenges. |
13,957 | Please write an abstract with title: A Novel Control Strategy for Suppression of HVDC Subsequent Commutation Failure, and key words: Limiting, Firing, Commutation, HVDC transmission, System recovery, Safety, Standards. Abstract: In the case of AC failures at the receiving end of the HVDC system, commutation failures are likely to occur, which may cause the converter station to lock up and seriously threaten the safety of the power grid. In order to suppress the subsequent commutation failure of HVDC, this paper studies the response of the electrical quantity and the control quantity when the system is in the recovery process. The DC current and the firing angle are not coordinated, resulting in insufficient commutation voltage-time area margin and the inability to complete the commutation process. For this reason, this paper proposes a subsequent commutation failure suppression strategy. By limiting the DC current when the firing angle overshoots, the subsequent commutation failure is suppressed to achieve effective recovery of the DC system. The CIGRE standard test model is used in EMTDC to test and verify the proposed theory. |
13,958 | Please write an abstract with title: Study on Statistical Characteristics of Audible Noise and Vibration Signals of UHV Transformers and Reactors, and key words: Vibrations, Power transformers, Oil insulation, Harmonic analysis, Inductors, Acoustic noise, Shunts (electrical). Abstract: Audible noise and vibration signals can reflect working conditions of transformers such as loose fasteners, winding deformation, and DC magnetic biasing, etc. In order to realize the transformer state assessment and early warning, noise and vibration signals are measured on site for 5 transformers, 4 shunt reactors, and 21 converter transformers. At least 4 measuring points are selected to collect noise signals, which include UHV transformer oil tank and cooler, the tank walls on both sides of the high-voltage bushing and the neutral point bushing. Meanwhile, 4-10 test points are arranged to measure vibration signals around the tested equipment, including the tap-changer, the iron core clamps, the high voltage bushing, and the tank wall near the cooler on both sides of high voltage bushing and the neutral point bushing. The parameters of SPL(Sound pressure level), vibration amplitude, odd-even harmonic ratio, high-frequency energy ratio, and spectrum complexity of the three types of test objects are statistically analyzed. |
13,959 | Please write an abstract with title: Low-Complexity Compressed Sensing Downlink Channel Estimation for Multi-Antenna Terminals in FDD Massive MIMO Systems, and key words: Channel estimation, Downlink, Antennas, Compressed sensing, Greedy algorithms, Massive MIMO. Abstract: In frequency division duplexing (FDD) massive multiple-input multiple-output (MIMO) systems, the overhead of downlink channel estimation is complex in terms of the pilot overhead, the calculation cost and the estimation process. In this paper, we propose a low-complexity downlink channel estimation scheme based on compressed sensing for mobile multi-antenna terminals. In the scheme, the mobile terminal estimates the downlink massive MIMO channel and utilises the characteristics of the spatial sparsity of the massive MIMO channel to reduce the feedback overhead by feeding back the nonzero value of the sparse channel. Specifically, we propose a low-complexity estimation algorithm based on compressive sensing for multi-antenna terminals to reduce the computational overhead of the terminal. Since different antennas of a terminal share the same support set, the algorithm estimates multiple indices per iteration, collecting the estimated indices of different antennas at the end of each iteration, thereby reducing the total number of iterations of the algorithm. Then, we derive a halting condition for a greedy algorithm that stops the iteration process according to the residual energy. The simulation results illustrate the efficiency of the halting condition for the greedy algorithm and the low complexity of the proposed algorithm. In contrast to different greedy algorithms and the Bayesian algorithm, the proposed algorithm has a complexity that decreases as the number of terminal antennas. |
13,960 | Please write an abstract with title: A storage based Virtual Synchronous System for Load-frequency regulation of interconnected Hybrid Microgrids using Selfish-herd optimiser, and key words: Biodiesel generator, Biogas generator, Microhydro generator, Selfish-herd optimizer, Solar-thermal power, Virtual synchronous system, Wind generator. Abstract: This paper is mostly focused on overcoming typical challenges due to renewable energy integration in hybrid microgrids, by incorporating coordinated energy storage-based virtual synchronous system (VSS). The work is initiated by proposing an unequal interconnected hybrid microgrid including Wind, Solar-thermal, Micro-hydro, Biogas, Biodiesel generating units with Battery and Super-capacitor based VSS. The load-frequency responses of the proposed system are compared for different scenarios of source and load variations with classical PID controllers using a recent Selfish-herd optimiser algorithm. Initially, the system responses are compared with 4-optimisation techniques to confirm the superior one. Then the system responses are compared with 3-scenarios of extreme source variations to analyse the effect of renewable penetration and VSS. Finally, the system frequency variations are reduced adequately by the inclusion of the proposed VSS and the responses of each scenarios are recorded. |
13,961 | Please write an abstract with title: Reducing Cell to Cell Variation of Lithium-Ion Battery Packs During Operation, and key words: Batteries, Aging, Discharges (electric), State of charge, Voltage measurement, Lithium-ion batteries, Resistance. Abstract: In this work, an experimental approach to reduce the variation from cell to cell during battery operation is evaluated to reach a better battery utilization. Numerous theoretical considerations of intelligent battery management systems without long-term experimental validation of their capabilities lead to a gap in the literature, which this work aims to address. For this purpose, the ageing behaviour of two batteries is investigated for almost 1.5 years. One battery is connected to an active balancing battery management system (BMS) and the other to a conventional passive balancing BMS. Important battery parameters, such as capacity and internal resistance, are recorded in each cycle. The battery behaviour is evaluated in detail by observing the voltage difference of the individual cells at the end of discharge and by calculating the amount of charge balanced by the BMS. Significant differences between the BMS systems used are elucidated, which illustrate the advantages of active balancing. In contrast to passive balancing, active balancing can reduce the ageing rate of the battery and achieve better utilization with a more than five times lower voltage spread at end of discharge, a up to 3.1% higher discharge capacity and a 7.7% longer service life. |
13,962 | Please write an abstract with title: Analysis and Control Development of IPM Traction Machines with Skewed Rotor using Unskewed Machine Model, and key words: Couplings, Industrial electronics, Analytical models, Torque, Current measurement, Conferences, Rotors. Abstract: The paper presents a simplified analysis and control development method for IPM traction machines with skewed rotor using unskewed machine model. It is shown that the skewed machine characteristics under a given set of dq-axis currents could be obtained from the unskewed machine model using relevant modified dq-axis currents associated with the skewed information. Therefore, under the proposed method, the tested IPM machine model with skewed rotor could be rapidly derived from the unskewed machine model without FEA implementation for each skewed slice. It is demonstrated that in comparison with the FEA-based model, the proposed method could maintain up to 0.2% difference for both stator flux linkage and torque maps over dq-axis currents applied as well as 0.1% efficiency difference map over main torque speed operation. The proposed method is validated by FEA and measurement from a high-speed high-power (8000rpm, 80kW) IPM traction machine with skewed rotor. |
13,963 | Please write an abstract with title: Research of long-time stability of an atomic magnetic resonance standard system for reproduction of direct current and magnetic flux density, and key words: Stability, Magnetic resonance, Solenoids, Measurement standards, Current measurement, Magnetic field measurement, Atomic measurements, Magnetometers, Magnetic flux density, Electrical resistance measurement. Abstract: At the D. I. Mendeleyev Institute for Metrology (VNIIM) a standard system using helium-4 atomic magnetic resonance has operated during the past 10 years for reproduction of low magnetic flux density and direct current. Research of the base elements of this system for the last 5 years have shown that non-stability of the coil-constant of a standard solenoid and nonlinearity of the frequency-to-current conversion coefficient of a quantum system for current reproduction in the range 0.1 A to 1 A are less than 1 /spl times/ 10/sup -7/. |
13,964 | Please write an abstract with title: Integrated Modeling and Analysis of PEMFC based on Model Parameters Identification, and key words: Analytical models, Temperature distribution, Heuristic algorithms, Fitting, Linear regression, Fuel cells, Control systems. Abstract: Based on mechanism analysis of proton exchange membrane fuel cell (PEMFC), a semi mechanism and semi empirical steady-state simplified model is established by adopting reasonable and necessary assumptions, which helps the study of fuel cell polarization curves. Taking external conditions such as temperature, pressure and current density as variables, the model identifies fitting parameters by linear regression according to the experimental data, which proves its strong universality and generalization ability. In order to further study the output characteristics of PEMFC, a dynamic model is established in Matlab/Simulink to reflect the changes of output voltage and internal gas components. Considering different operating conditions and current requirements, the model is conductive to optimizing the structural design of the PEMFC, improving its operating performance and developing a real time control system. |
13,965 | Please write an abstract with title: Coherent spectral narrowing of the faraday rotation in Rb vapor nanocell, and key words: Optimized production technology, Fluorescence, Venus, Absorption, Frequency modulation. Abstract: Faraday rotation in a nanocell with smoothly variable thickness L of Rb atomic vapor column in the range 140-1700 nm has been obtained. Unusual behavior of Faraday rotation versus the ratio L/lambda (lambda = 780 nm) has been studied |
13,966 | Please write an abstract with title: Simulation Study on Probabilistic Time Series Output of Large-scale Wind Farm under the Generation-grid-load-energy Storage Collaborative Control Scenario, and key words: Wind speed, Load modeling, Time series analysis, Wind farms, Probability distribution, Wind power generation, Collaboration. Abstract: The generation-grid-load-energy storage collaborative control lacks effective simulation and testing methods currently, scenario simulation and verification is an effective solution. This paper first describes the architecture of the generation-grid-load-energy storage collaborative control scenario, then focuses on the method of generating wind speed with chronological characteristics. The wake effect in large-scale wind farms and the differences between day and night should be taken into account. Finally, the large-scale wind farm output under the scene simulation is modeled. The timing output of the wind farm is also calculated and compared with the output power of an actual wind farm. The rationality and correctness of the probabilistic timing output simulated in this paper are verified. |
13,967 | Please write an abstract with title: Mode-locked Nd:YVO/sub 4/ laser with 157 GHz repetition rate, and key words: Laser mode locking, Bandwidth, Optical pulses, Laser theory, Optical distortion, Optical filters, Ultrafast optics, Laser noise, Power lasers, Pump lasers. Abstract: Summary form only given. Recently, we have demonstrated passively mode-locked miniature Nd:YVO/sub 4/ lasers with up to 77 GHz repetition rate. Here we show that mode locking is possible even at /spl ap/157 GHz, although this repetition rate is already /spl ap/60% of the FWHM gain bandwidth so that most of the power is delivered in a single longitudinal mode. Nevertheless the pulses are still reasonably well separated. We also show that Q-switching instabilities can be suppressed even at these high pulse repetition rates. |
13,968 | Please write an abstract with title: Context-based segmentation of image sequences, and key words: Image segmentation, Image sequences, Humans, Image analysis, Feature extraction, Computer vision, Data mining, Clustering algorithms, Jacobian matrices, Parametric statistics. Abstract: We describe an algorithm for context-based segmentation of visual data. New frames in an image sequence (video) are segmented based on the prior segmentation of earlier frames in the sequence. The segmentation is performed by adapting a probabilistic model learned on previous frames, according to the content of the new frame. We utilize the maximum a posteriori version of the EM algorithm to segment the new image. The Gaussian mixture distribution that is used to model the current frame is transformed into a conjugate-prior distribution for the parametric model describing the segmentation of the new frame. This semisupervised method improves the segmentation quality and consistency and enables a propagation of segments along the segmented images. The performance of the proposed approach is illustrated on both simulated and real image data. |
13,969 | Please write an abstract with title: Multi-trace Single Source Equations for the Modelling of Partially Coated Composite Structures, and key words: Conferences, Scattering, Mathematical models, Coatings, Boundary-element methods, Periodic structures. Abstract: Multi-trace boundary element methods have become a robust and relatively easy to implement technique for the modelling of scattering and transmission by composite targets. To counteract the doubling of unknowns inherent to multiple-trace methods, the central idea of inserting a gap at the interface between domains can be applied to the single source equations (as opposed to the PMCHWT equation). In this contribution, a well-conditioned multi-trace single source method is introduced for the modelling of scattering by composite devices that may include perfectly conducting regions and perfectly conducting coatings. |
13,970 | Please write an abstract with title: Effect of space con conduction current and breakdown of polyimide films, and key words: Electric breakdown, Polyimides, Conductive films, Space charge, Current measurement, Charge measurement, Pulse measurements, Distortion measurement, Thick film circuits, Thickness measurement. Abstract: We have been studying the breakdown characteristics of polyimide (PI) films. The purpose of this study is to clarify the effect of space charge on conduction current and breakdown of PI films. The space charge distributions and external circuit current (lex) just before the breakdown of a 125 /spl mu/m thick PI films were simultaneously measured by using pulsed electro-acoustic (PEA) method in 363 K (90 /spl deg/C). We tried to observe the change of space charge distribution just before the breakdown of PI films obtained by very short period interval (2 ms) measurement. lex showed a large increase, however the remarkable change of space charge distribution just before the breakdown did not show. These results showed that the breakdown of PI films is not directly caused by the distortion of the electric field, but is caused by a thermal breakdown process due to the conduction current by the temperature rise of the sample. The simultaneous measurement of transient space charge profiles and lex must contribute to the investigation of conduction and breakdown phenomena of PI films. |
13,971 | Please write an abstract with title: Dual Layer Least Mean Fourth Based Control of Grid-Interfaced Wind Turbine Coupled DFIG with Reduced Current Sensors, and key words: Reactive power, Wind speed, System performance, Doubly fed induction generators, Rotors, Prototypes, Stators. Abstract: This paper presents a dual layer least mean fourth adaptive filter based algorithm for the grid side converter (GSC) control of a wind turbine driven doubly fed induction generator (DFIG) to extract the active fundamental weights of both load and stator currents in grid connected mode. This is essentially eliminates the use of phase locked loop, abc to dq and dq to abc transformations in GSC control as compared to conventional synchronous reference frame based vector control. Moreover, a reduced sensor based control is incorporated in the rotor side converter (RSC) control of DFIG. In this, rotor currents are estimated in stationary reference frame from sensed stator currents and stator voltages. Therefore, in totality, it reduces two current sensors and results in lower cost and less complexity of the system. To qualify the system performance, simulations are carried out under linear and nonlinear loads, constant and varying wind speed, and nonlinear unbalanced loads. The total harmonic distortions of currents and voltages, are obtained as specified in the standard of the IEEE 519. Moreover, both the grid and DFIG stator are operated at unity power factor. Finally, the system steady state and dyamic performances, are verified on a prototype developed in the laboratory. |
13,972 | Please write an abstract with title: A Physics-Based Neural Network (PNN) Approach to Solving the Heterogeneous Nonlinear Fullwave Equation, and key words: Ultrasonic imaging, Diffraction, Computational modeling, Neural networks, Graphics processing units, C languages, Media. Abstract: The fullwave equation describes nonlinear acoustic wave propagation in a heterogenerous medium, which accounts for the linear propagation of the wave, thermoviscous diffusivity, nonlinearily, attenuation, and variation in density. Numerical solutions of the fullwave equation, including the Fullwave and k-wave toolboxes, are used in medical ultrasound imaging research. However, despite of the wide applications of these numerical tools, they are computationally intensive. We propose a physics-based neural network (PNN) approach to numerically solving the fullwave equation that describes the nonlinear propagation in a heterogeneous nonattenuating medium. The proposed network has been implemented in PyTorch and its structure is based on the fullwave equation. The structure and weights of the proposed neural network have clear physical interpretations. As a proof-of-concept demonstration, we show in this work the simulations of the propagation of acoustic pulses through a representation of the human abdomen, as well as through water. The flexibility of the physics-based neural network implementation enables the migration of computation from CPU to GPU with minimal additional efforts, which accelerates the computation by a factor of 12 compared to the Fullwave toolbox on CPU. |
13,973 | Please write an abstract with title: Synchronous-Variable-Frequency Control of Bidirectional DCM Interleaved DC–DC Converter for Wide-Range Enhanced Efficiency, and key words: Inductors, DC-DC power converters, Switches, Batteries, Voltage control, Switching frequency, Frequency control. Abstract: A bidirectional discontinuous-conduction-mode constant on-time variable-frequency control strategy for a three-phase interleaved dc–dc converter suitable for traction applications is proposed in this article. The strategy enhances the converter efficiency at low-power conditions, providing fairly constant efficiency over the entire power range, by synchronously controlling both the bottom and top switches of the three boost phases. Simulation and experimental results demonstrate the validity and effectiveness of the proposed approach on a 10-kW bidirectional interleaved boost converter. |
13,974 | Please write an abstract with title: Stepwise Domain Adaptation (SDA) for Object Detection in Autonomous Vehicles Using an Adaptive CenterNet, and key words: Object detection, Detectors, Training, Deep learning, Feature extraction, Adaptive systems, Task analysis. Abstract: In recent years, deep learning technologies for object detection have made great progress and have powered the emergence of state-of-the-art models to address object detection problems. Since the domain shift can make detectors unstable or even crash, the detection of cross-domain becomes very important for the design of object detectors. However, traditional deep learning technologies for object detection always rely on a large amount of reliable ground-truth labelling that is laborious, costly, and time-consuming. Although an advanced approach CycleGAN has been proposed for cross-domain object detection tasks, the ability of CycleGAN to reduce the divergence across domains at the feature level is limited. In this paper, a stepwise domain adaptation (SDA) detection method is proposed to further improve the performance of CycleGAN by minimizing the divergence in cross-domain object detection tasks. Specifically, the domain shift is addressed in two steps. In the first step, to bridge the domain gap, an unpaired image-to-image translator is trained to construct a fake target domain by translating the source images to the similar ones in the target domain. In the second step, to further minimize divergence across domains, an adaptive CenterNet is designed to align distributions at the feature level in an adversarial learning manner. Our proposed method is evaluated in domain shift scenarios based on the driving datasets including Cityscapes, Foggy Cityscapes, SIM10k, and BDD100K. The results show that our method is superior to the state-of-the-art methods and is effective for object detection in domain shift scenarios. |
13,975 | Please write an abstract with title: Variable gain amplifier in polar loop modulation transmitter for EDGE, and key words: Gain, Transmitters, Radiofrequency amplifiers, Circuit topology, Inverters, Amplitude modulation, Circuit noise, Linearity, Radio frequency, RF signals. Abstract: A variable gain amplifier and a polar loop modulation transmitter are presented. This variable gain amplifier is used to add amplitude modulation to a phase-modulated RF signal. For the circuit topology, CMOS inverter topology is adopted because of its good noise and linearity performances. Moreover, the basic inverter topology is modified to enlarge the variable gain range. From a PA point of view, the polar loop modulation transmitter is equivalent to a direct conversion transmitter, because their RF output signals have complete modulation information. The advantage of the polar loop modulation transmitter is that there is no VCO pulling problem. |
13,976 | Please write an abstract with title: Single event transients in operational amplifiers, and key words: Operational amplifiers, Circuit testing, Power amplifiers, Space technology, Voltage, Ion beams, Cyclotrons, Oscilloscopes, Pulse amplifiers, Amplitude estimation. Abstract: A number of bipolar operational amplifiers have been evaluated for single event effects for possible use in a space application. Various trigger thresholds were used to estimate the distribution of transient amplitudes. |
13,977 | Please write an abstract with title: Privacy-Preserving Federated Multi-Task Linear Regression: A One-Shot Linear Mixing Approach Inspired By Graph Regularization, and key words: Conferences, Linear regression, Signal processing algorithms, Signal processing, Multitasking, Prediction algorithms, Acoustics. Abstract: We investigate multi-task learning (MTL), where multiple learning tasks are performed jointly rather than separately to leverage their similarities and improve performance. We focus on the federated multi-task linear regression setting, where each machine possesses its own data for individual tasks and sharing the full local data between machines is prohibited. Motivated by graph regularization, we propose a novel fusion framework that only requires a one-shot communication of local estimates. Our method linearly combines the local estimates to produce an improved estimate for each task, and we show that the ideal mixing weight for fusion is a function of task similarity and task difficulty. A practical algorithm is developed and shown to significantly reduce mean squared error (MSE) on synthetic data, as well as improve performance on an income prediction task where the real-world data is disaggregated by race. |
13,978 | Please write an abstract with title: Wireless, ESL, DFM, and Power on Stage at 42nd DAC, and key words: Design for manufacture, Circuit testing, System testing, Electronic equipment testing, Software testing, Automatic testing, Logic testing, Integrated circuit testing, Electronic design automation and methodology, Embedded software. Abstract: The 42nd Design Automation Conference, the world's leading conference and exhibition for design automation, took place in Anaheim, California, from 13 to 17 June 2005. This year's DAC featured a special industry theme day, "Wireless Wednesday," and two keynote talks, by Bernard Meyerson of IBM and Ron Rohrer of Cadence. The technical program explored front-end design issues at the electronic system level (ESL), and various topics linking design and manufacturing. DAC 2006 will take place in San Francisco, California, from 24 to 28 July 2006. |
13,979 | Please write an abstract with title: Boosting as a dimensionality reduction tool for audio classification, and key words: Boosting, Principal component analysis, Covariance matrix, Clustering algorithms, Matrix decomposition, Scattering, Pattern classification, Singular value decomposition. Abstract: In this paper we present a modified AdaBoost algorithm that can be used for dimensionality reduction in audio classification problems. The algorithm is modified to work as a feature selector for a four way classification problem. It is compared with principal component analysis (PCA), which is a popular tool for reducing the dimensions of high-dimensional data without losing significant scatter information. Both algorithms are applied to a four way audio classification problem and the results are presented. |
13,980 | Please write an abstract with title: Reduction of DC-bus capacitor ripple current with PAM/PWM converter, and key words: Capacitors, Pulse width modulation converters, Pulse width modulation, Pulse width modulation inverters, Heating, Voltage, Variable speed drives, Failure analysis, Chemicals, Degradation. Abstract: Electrolytic capacitors are used in nearly all adjustable-speed drives, and they are one of the components most prone to failure. The main failure mechanisms include loss of electrolyte through outgassing and chemical changes to the electrolyte and oxide layer. All the degradation mechanisms are exacerbated by ripple current heating. Since the equivalent series resistance of electrolytic capacitors is a very strong function of frequency it must be properly modeled to accurately calculate the power loss. In this paper, a method to reduce the ripple current in a constant Volts/Hertz pulse-amplitude-modulation (PAM)/pulsewidth-modulation (PWM) converter driving an induction motor is investigated. The dc-bus voltage amplitude is reduced in proportion to speed by a buck or current stiff rectifier and the PWM modulation index is maintained at a high level to achieve a reduced ripple current below base speed. By comparison with a diode-bridge-fed PWM voltage stiff inverter, it is shown that the PAM/PWM mode of operation can lead to a significant reduction in capacitor power loss leading to increased capacitor lifetime or decreased capacitor size. The capacitor heating is analyzed using numerical and analytical techniques. Experimental results are provided to verify the analytical results. |
13,981 | Please write an abstract with title: Theory of MSSW Convolution, and key words: Convolution, Frequency, Magnetostatic waves, Convolvers, Magnetization, Voltage, Equations, Geometry, Bandwidth, Surface waves. Abstract: The present work reports a theoretical study of the convolution of contra-propagating magnetostatic surface waves (MSSWs) in a YIG film. Computations of the induced convolution voltage in a pickup loop and the internal efficiency of the convolution process are presented as functions of frequency as well as the thickness of the YIG film. In agreement with expectation, the convolution voltage goes down with increase in frequency or thickness of the YIG film, i.e., with increased decoupling of the two contra-propagating MSSWs. The bandwidth for convolver operation is predicted to be better for MSSW than for magnetostatic forward volume waves (MSFVWs) or magnetostatic backward volume waves (MSBVWs) |
13,982 | Please write an abstract with title: Is this robot like me? Links between human and robot personality traits, and key words: Robot sensing systems, Human robot interaction, Humanoid robots, Social implications of technology. Abstract: A relatively unexplored question for human-robot social interaction is whether a robot's personality should match that of the human user, or be different in the sense that humans do not want the robot to be like them. In this study, 28 adults interacted individually with a non-humanoid robot that demonstrated two robot behaviour styles (socially interactive, socially ignorant) in a simulated living room situation. Questionnaires assessed the extent to which adult ratings of their own personality traits were similar or different to the two robot behaviours. Results revealed that overall subjects did not view their own personality as similar to either of the two robot behaviour styles. Subjects viewed themselves as having stronger personality characteristics compared to the two robot behaviour styles. Important group differences were found, factors such as subject gender, age and technological experience were important in how subjects viewed their personality as being similar to the robot personality. Design implications for future studies are discussed. |
13,983 | Please write an abstract with title: Adaptive selective kernel learning algorithms, and key words: Kernel, Support vector machines, Least squares methods, Nonlinear equations, Training data, Ear, Least squares approximation, Image processing, Nonlinear optics, Optical character recognition software. Abstract: This paper studies kernel regression problems. The focus is on studying kernel algorithms that use the least squares criterion and developing methods so that the solution in the dual observation space intelligently chooses training examples. The least squares-support vector machine (LS-SVM) and variants have attracted researchers as the solution to nonlinear problems can be formulated as an optimization problem that involves finding a solution to a set of linear equations in the primal or dual spaces. A drawback of using the LS-SVM is that the solution is not sparse, but involves a solution to a set of linear equations in the dual space that is dependent on the number of observations. This paper discusses an on-line algorithm that selectively chooses to add and delete training observations. Through examples we show that this algorithm can outperform LS-SVM solutions that use a larger window of randomly trained examples. |
13,984 | Please write an abstract with title: Behavioral Tracking and Inference Algorithm Using Skeleton Vector Information Analysis, and key words: Solid modeling, Three-dimensional displays, Inference algorithms, Skeleton, Angular velocity, Data mining, Information analysis. Abstract: This paper proposed a behavioral tracking and inference algorithm by skeleton vector information analysis. The proposed algorithm uses only RGB+D information to track and inference using CCTV images without additional equipment. First, the articulated points of action are extracted from the extracted RGB+D image. And the continuous vector data is then calculated using the relation vector expression at the extracted action point. Then, continuous vector data is applied to nonlinear inference curve expressions to inference angular velocity and state of shaking. Apply the learned model to various datasets to verify the accuracy of behavioral tracking and inference. As a result, simulations of 3D action information have demonstrated significant performance differences. |
13,985 | Please write an abstract with title: State-of-charge estimation for lithium-ion battery pack based on Unscented Kalman Filter considering cell inconsistency, and key words: Lithium-ion batteries, Computational modeling, Estimation, Discharges (electric), Batteries, Safety, State of charge. Abstract: The accuracy of battery state of charge (SOC) estimation has tremendous value in the safe use of battery. However, inconsistencies between batteries will affect the power and usable capacity. When vehicle battery pack contains hundreds of single cell, more efforts should be devoted to develop a high-precision and low-complexity method of SOC estimation. In the article, a mean-difference model (MDM) has been established to precisely characterize the battery characteristics, in which the thevenin model is chosen to be mean model (MM) to characterize the whole battery pack features, and the rint model is used to evaluate the inconsistency between batteries. The mean difference model parameters are identified by means of forgetting factor least square (FFRLS), and then the SOC were estimated by the unscented kalman filter (UKF). The validity of MDM and the UKF is verified on a small series battery pack at last. |
13,986 | Please write an abstract with title: Transactional HashMaps in the Myrrh Framework, and key words: Data structures, Yarn, Java, System recovery, Computer languages, Error correction, Computer bugs, Computer science, Concurrency control, Programming profession. Abstract: To improve the performance of transactional programming, we propose a new class of transactional data structures and introduce a transactional version of Java's HashMap class. This specialized HashMap class enables developers to take full advantage of the atomic and isolated properties of transactions in order to support concurrent access to different parts of a map. Furthermore, the validation and conflict resolution algorithm executed as part of the commit step resolves most types of potential conflict, thus allowing all transactions that don't directly conflict to commit. By using transactions to eliminate contention, and a specialized implementation of the HashMap class to resolve conflicts at commit-time, we significantly improve the efficiency of transactional programming |
13,987 | Please write an abstract with title: A Robust Method with DropBlock for Face Anti-Spoofing, and key words: Deep learning, Databases, Fuses, Face recognition, Neural networks, Reliability, Faces. Abstract: Face anti-spoofing is an important component for reliable face recognition. Previous deep learning methods usually exploit a large network structure and are prone to be overfitting when the face anti-spoofing database is a small scale. And in some occasions, multi-frame information or other auxiliary information is not available. In order to address these issues, we propose an end-to-end deep learning approach with DropBlock layer to distinguish between a fake face and a genuine face, which makes use of frame-only RGB image. In this paper, we evaluate the proposed approach with different settings on three popular databases, i.e., REPLAY-ATTACK, CASIA-FASD, and CASIA-SURF. The proposed approach can achieve competitive results on these databases. The experimental results show that our model is more robust and can learn more generalized features for face anti-spoofing. |
13,988 | Please write an abstract with title: Coordinated Control Strategy for Ship Wind Power Hybrid Energy Storage, and key words: Fluctuations, Switches, Wind power generation, Supercapacitors, Lithium batteries, Control systems, Hybrid power systems. Abstract: Aiming at the characteristics of unstable wind power during the ship's sailing process, this paper uses a multi-lithium battery-supercapacitor hybrid energy storage system to store electrical energy, and stabilizes the severe fluctuations in wind power. The utilization of electrical energy in the ship's power grid has been improved. Utilizing the fast charging and discharging characteristics of supercapacitors, a control strategy for supercapacitor switching charging and discharging was designed to improve the energy utilization rate. |
13,989 | Please write an abstract with title: DMA Function Verification Based on UVM Verification Platform, and key words: Integrated circuits, Micromechanical devices, Memory management, IP networks, Hardware design languages. Abstract: This article describes the UVM verification platform built with system verilog language, which realizes the functional verification of Direct Memory Access, and achieves verification of the correctness of DUT functions and coverage statistics. The verification results show that DMA functions correctly in different working modes, and the coverage rate has reached 100% collection. The UVM verification platform has high flexibility, can greatly improve the verification efficiency and the reusability of the verification platform, and meet the needs of IC verification. |
13,990 | Please write an abstract with title: Global-and-Local Collaborative Learning for Co-Salient Object Detection, and key words: Semantics, Task analysis, Feature extraction, Convolution, Object detection, Computational modeling, Collaborative work. Abstract: The goal of co-salient object detection (CoSOD) is to discover salient objects that commonly appear in a query group containing two or more relevant images. Therefore, how to effectively extract interimage correspondence is crucial for the CoSOD task. In this article, we propose a global-and-local collaborative learning (GLNet) architecture, which includes a global correspondence modeling (GCM) and a local correspondence modeling (LCM) to capture the comprehensive interimage corresponding relationship among different images from the global and local perspectives. First, we treat different images as different time slices and use 3-D convolution to integrate all intrafeatures intuitively, which can more fully extract the global group semantics. Second, we design a pairwise correlation transformation (PCT) to explore similarity correspondence between pairwise images and combine the multiple local pairwise correspondences to generate the local interimage relationship. Third, the interimage relationships of the GCM and LCM are integrated through a global-and-local correspondence aggregation (GLA) module to explore more comprehensive interimage collaboration cues. Finally, the intra and inter features are adaptively integrated by an intra-and-inter weighting fusion (AEWF) module to learn co-saliency features and predict the co-saliency map. The proposed GLNet is evaluated on three prevailing CoSOD benchmark datasets, demonstrating that our model trained on a small dataset (about 3k images) still outperforms 11 state-of-the-art competitors trained on some large datasets (about 8k–200k images). |
13,991 | Please write an abstract with title: A Non-Meaningful Game: The Case for Redefining Meaningful Play, and key words: Meaningful Play, Experimental Design, Game Design, Video Games, Feedback Systems. Abstract: This paper explores the concept of meaningful play in the context of a game that subverts the traditional input-output understanding of the term. This paper delves into the factors that contribute to the understanding of meaningful play. Using this understanding, a non-meaningful game was constructed that challenges the conventional notion of meaningful play by creating the illusion of player input and impact on the game system without any actual player input or game feedback. By analyzing the non-meaningful game, this paper contributes to the ongoing conversation around meaningful play, indicating a need for a new definition. Lastly, through the creation of a game void of actual player input, this paper illustrates the importance of player perception and belief in constructing meaning within games. This questions the modern understanding of video games and opens new avenues for further research in the field of game studies. |
13,992 | Please write an abstract with title: Circuit modeling for neuromorphic photonics in Verilog-A as a scalable simulation platform, and key words: Performance evaluation, Neuromorphics, Simulation, Waveguide lasers, Optical coupling, Optical modulation, Integrated circuit modeling. Abstract: We demonstrate a Verilog-A based approach to perform electro-optical co-simulation for neuromorphic architectures. Verilog-A models of primary photonic devices are discussed along with comparing the simulation and experimental results. |
13,993 | Please write an abstract with title: A New Approach to a Reliable Time Multiplexed Switch, and key words: Switches, Phase change materials, Holography, Communication switching, Redundancy, Error correction codes, Scattering, Visualization, Protection, Communications Society. Abstract: Conventional designs for the time-multiplexed space-division switch used in PCM switching networks employ spatial redundancy (duplication) to assure adequate reliability. An alternative technique is described which employs a combination of coding redundancy and holographic temporal scattering to achieve reliability without duplication. |
13,994 | Please write an abstract with title: A metal-oriented layout structure for CMOS logic, and key words: CMOS logic circuits, CMOS technology, Microcell networks, Assembly, Design methodology, Logic design, Application specific integrated circuits, CMOS digital integrated circuits, Integrated circuit technology, Design automation. Abstract: A design method is described for the realization of large digital modules of random logic for custom integrated circuits in CMOS technology. The layout structure is based on the gate matrix concept with a metal orientation instead of a polysilicon orientation. The symbolic layout is obtained by using 11 different microcells with simple assembly rules. It is derived from the functional specifications of the circuit (Karnaugh maps) using a very simple and attractive method. A CAD program for translating the symbolic layout into a geometrical one is described. It works by assembling geometrical microcells. The advantages and disadvantages of the metal-oriented structure are analyzed through examples of industrial designs. The technique is not suitable for fast circuits. However, it results in an improvement of productivity by a factor of about four and a packing density for large modules which is at least comparable with that of nonoriented hand layouts. |
13,995 | Please write an abstract with title: Unsupervised Learning Neural-Network Method for Resource Allocation in Multi-cell Cellular Networks, and key words: Cellular networks, Energy consumption, Simulation, Power control, Artificial neural networks, Channel allocation, Energy efficiency. Abstract: In order to meet requirements of high speed, low energy consumption and low latency of resource allocation in multi-cell cellular networks, an unsupervised learning based resource allocation method is proposed. The unsupervised learning based resource allocation method contains an unsupervised learning based power control neural network (NNPC) and an unsupervised learning based channel allocation neural network (NNCA). The NNPC is constructed to output optimized channel power to maximize the expectation of linear weighted sum of transmission rate and energy efficiency, and the NNCA is constructed to combine the NNPC to further optimize the expectation of linear weighted sum of transmission rate and energy efficiency. The simulation results show that the proposed method can obtain better transmission rate and energy efficiency than other algorithms under the premise of ensuring low delay. |
13,996 | Please write an abstract with title: White Spaces and Database‐assisted Spectrum Sharing, and key words: White spaces, TV, Wireless communication, Licenses, Regulators, Receivers, Wireless sensor networks. Abstract: This chapter provides an overview of the evolution of electromagnetic spectrum sharing, building on the emergence of the cognitive radio concept, to enable more efficient access to spectrum without the need for conventional licensing. Studies on the coexistence of long‐term evolution with broadcast in the ultra high frequency bands and for TV white space in the same bands have helped regulators evolve their methods for determining the coexistence rules that will facilitate more intensive spectrum sharing. Given the growing importance of spectrum to national economies, regulators around the world have been pondering how to use it more efficiently. Related to this is the question of how efficiency can be defined and measured. Spectrum sharing requires coordination between the users of a particular band to ensure that co‐habiting applications do not disrupt each other, which we refer to as harmful interference. |
13,997 | Please write an abstract with title: From Sensing to Acting—Can Pervasive Computing Change the World?, and key words: Sensors, Pervasive computing, Actuators, Robot sensing systems, Computational modeling, Artificial intelligence. Abstract: Computing technology has indeed become pervasive. Taking a quick look around me, I see computing systems in literally everything—in the cars, televisions, smartphones, restaurants, ski-lifts, heating systems, sports trackers, medical devices, etc. This has been realized by a tremendous development in hardware and software technology in terms of CPUs, memory, sensors, operating systems, network, display, etc. However, looking back at this technology development—and the research done in the field—it strikes me that something is missing. One of the grand visions was to make the computer “invisible,” as framed by Weiser. But it seems like instead of computing becoming more invisible, it is taking up more of the user’s attention. In this article, I argue that this is because (pervasive) computing has only come halfway. Much effort has been done in terms of sensing and understanding the world around the user, while much less effort has been put into helping the user actually doing anything. By providing examples mostly taken from the medical domain, this article discusses if moving from “sensing” and “thinking” to actually “doing” something is possible and what challenges are associated with this movement. |
13,998 | Please write an abstract with title: Crawling for domain-specific hidden Web resources, and key words: Crawlers, Databases, Information analysis, Search engines, Europe, Web pages, HTML, Humans, Computer science, Information resources. Abstract: The Hidden Web, the part of the Web that remains unavailable for standard crawlers, has become an important research topic during recent years. Its size is estimated to 400 to 500 times larger than that of the publicly indexable Web (PIW). Furthermore, the information on the hidden Web is assumed to be more structured, because it is usually stored in databases. In this paper, we describe a crawler which starting from the PIW finds entry points into the hidden Web. The crawler is domain-specific and is initialized with pre-classified documents and relevant keywords. We describe our approach to the automatic identification of Hidden Web resources among encountered HTML forms. We conduct a series of experiments using the top-level categories in the Google directory and report our analysis of the discovered Hidden Web resources. |
13,999 | Please write an abstract with title: Development of a Hybrid Rotor Structure for high-speed Laminated Rotor Induction Motor, and key words: Torque, Induction motors, Three-dimensional displays, Lamination, Rotors, Conductivity, Steel. Abstract: The selection of materials poses a big challenge in the design of high-speed induction machines. For high efficiency levels, induction motors with copper bars in the rotor are preferred. However, the die-cast copper rotor structure cannot withstand the high centrifugal force during the high-speed operation. The easy solution is to employ materials with high yield strength. However, materials with higher strengths often have a reduced electrical conductivity. This necessitates the need for increasing the rotor volume to compensate for the reduction in torque. Thereby, increasing the inertia of the rotor. A novel rotor design with a high conducting material for the rotor bars and a high strength alloy for the end rings to reduce the stress levels in the rotor is proposed in this paper. Thus, allowing the use of conventional electrical steel like M235-35A instead of high tensile strength lamination. This structure is suggested for high-speed spindle application. The hybrid rotor structure also promises to offer the least rotor inertia. A 2D FE analysis for electromagnetic performance and 3D mechanical stress analysis is performed to validate the proposed rotor design. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.