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6,800 | Please write an abstract with title: Improving the Efficiency of Embedded Data Logging on NAND Flash for IoT Systems, and key words: Performance evaluation, Embedded systems, Simulation, Conferences, Time series analysis, Internet of Things, Flash memories. Abstract: A key requirement for many Internet of Things (IoT) systems is the collection and storage of time-based sensed data. Edge-devices are typically embedded systems with limited capabilities and power constraints. The fundamental challenge of storing time series data on embedded systems with raw flash memory has received minimal attention. This work develops an efficient technique for providing record-level consistency that significantly improves upon the typical, sequential storage approach. Simulation results demonstrate a reduction in the memory operations performed, time spent on data storage, energy consumed, and memory wear on the device. |
6,801 | Please write an abstract with title: Blockchain for Power Grids, and key words: Peer-to-peer computing, Microgrids, Phasor measurement units, Fabrics. Abstract: Sharing information is an important part of regulating and maintaining efficient and safe power grids. This project's goal is to develop a way of using blockchain technology to share transaction information among different power grids in a secure, controlled, monitored, and efficient manner. The biggest concern regarding the data is integrity. By leveraging blockchain technology, the data will be reliable and resilient to attacks, such as man-in-the-middle and data spoofing attacks. The Hyperledger Fabric implementation provides a permissioned network in which power grids will act as nodes that maintain ledger information. By using a distributed ledger to validate transactions though the process of consensus, the system can share information in a manner that is more secure and transparent than traditional information sharing systems in which data is less secure and takes longer to validate. The additional layers of security and speed that Hyperledger technology provide help to prevent issues, such as power grid failures, that could stem from the latency or integrity issues involved with traditional methods of validating, processing, and reacting to shared data. |
6,802 | Please write an abstract with title: Training Fuzzy Neural Network via Multiobjective Optimization for Nonlinear Systems Identification, and key words: Fuzzy neural networks, Training, Optimization, Complexity theory, Convergence, Fuzzy control, Approximation algorithms. Abstract: The design of a fuzzy neural network (FNN) has long been a challenging problem since most methods rely on approximation error to train an FNN, which may easily result in overfitting phenomenon to degrade the generalization performance. To improve the generalization performance, an FNN with a multiobjective optimization algorithm (MOO-FNN) is proposed in this article. First, the multilevel learning objectives are designed around the generalization performance to guide the training process of an FNN. Then, the method utilizes the approximation error, the structure complexity, and the output smoothness indicators instead of a single indicator to improve the evaluation accuracy of generalization performance. Second, an MOO algorithm with continuous–discrete variables is developed to optimize the FNN. Then, MOO is able to use a novel particle update method to adjust both the structure and parameters rather than adjusting them separately, thereby achieving suitable generalization performance of the FNN. Third, the convergence of MOO-FNN is analyzed in detail to guarantee its successful applications. Finally, the experimental studies of MOO-FNN have been performed on model identification of nonlinear systems to verify the effectiveness. The results illustrate that MOO-FNN has a significant improvement over some state-of-the-art algorithms. |
6,803 | Please write an abstract with title: Film Slicks on the Sea Surface: Their Dynamics and Remote Sensing, and key words: Radar, Surface waves, Sea surface, Radar remote sensing, Remote sensing, Shape, Motion pictures. Abstract: Two aspects of the problem of marine film slicks and their remote sensing are considered. The first one is the slick evolution accounting for the action of wind waves. Results of field experiments with surfactant spills are presented and the along-wind and cross-wind axes of slicks as functions of time at different environmental conditions are discussed. A model of slick evolution taking into account surface stresses induced by wind waves is developed and is shown to be consistent with experiment. The second considered aspect of the problem is related to remote sensing of marine films using X-/C-/S-band two-polarized radar. Experiments with artificial slicks have indicated that both Bragg and non polarized scattering significantly contributes to the radar return, and the depression of radar backscatter in slicks as a function of radar wave number can be strongly different for Bragg and non polarized components. |
6,804 | Please write an abstract with title: Estimation of pole zero displacements of a digital filter due to coefficient quantization, and key words: Poles and zeros, Digital filters, Quantization, Fast Fourier transforms, Filtering, Transfer functions, Fourier transforms, Spectral analysis, Gold, Signal processing. Abstract: An analytical technique for estimating the displacement of poles and zeros of a digital filter due to multiplier coefficient quantization is presented. The proposed technique allows rapid evaluation of quantization effects in different realizations of a given transfer function. Also advanced here is a simple extension of the method to determine, a priori, coefficient word lengths which insure that the polezero movements will remain within prescribed bounds. Examples illustrating the technique are included. |
6,805 | Please write an abstract with title: Recurrence quantification analysis detects P300 on single-trial EEG, and key words: Complex networks, Electroencephalography, Complexity theory. Abstract: In the present paper, Recurrence Quantification Analysis was applied to detect event-related potential P300 on single-trial EEG. We demonstrated that the emergence of P300 is associated with EEG complexity increase. Besides, the RQA measure of complexity based on recurrence times quantification is sensitive enough to detect these changes on single-trial EEG. |
6,806 | Please write an abstract with title: Electrooptic light modulation technology, and key words: Electrooptic modulators, Optical modulation, Microwave technology, Microwave photonics, Optical waveguides, Nonlinear optics, Frequency, Electrodes, Ultrafast optics, Microwave devices. Abstract: Electrooptic light modulators are one of key elements to materialize future photonic systems for info-communication and instrumentation technologies. A number of possible MWP applications have been proposed and investigated, while a few practical devices have been implemented. With the recent growing interest in this area, we can expect rapid development in the utilization of lightwave technologies in microwave engineering, exploiting the potentiality in microwave and lightwave interactions through electrooptic effects. |
6,807 | Please write an abstract with title: Silicon nanocrystals precipitation in a SiO/sub 2/ matrix elaborated from the decomposition of LPCVD SiO/sub x/, and key words: Silicon, Nanocrystals, Annealing, Temperature, Spectroscopy, Matrix decomposition, Thermal decomposition, Inductors, Ellipsometry, Fourier transforms. Abstract: In this paper, we present results of a study which aims to obtain silicon nanocrystals (Si/sub nc/) embedded in a thin SiO/sub 2/ matrix, using high temperature annealing, from the thermal decomposition of SiO/sub x/. So, thin SiO/sub x/ films (4-10 nm) are grown from a N/sub 2/O/SiH/sub 4/ mixture in an industrial LPCVD reactor with different process parameters. Spectroscopic ellipsometry and Fourier transform infrared spectroscopy are used both to determine the stoichiometry of the SO/sub x/ and the decomposition state of the film after high temperature annealing. X-ray photoelectron spectroscopy confirms the completion of the reaction after annealing at 1000/spl deg/C for 15 minutes and transmission electron microscopy shows that the crystallinity of the silicon dots is dependent both on the stoichiometry of the SiO/sub x/ film and on the annealing temperature. Finally, some electrical results are presented and they show charge trapping in the SiO/sub x/ LPCVD layer. |
6,808 | Please write an abstract with title: The device of digital data processing from the fibre-optical sensor of mechanical values, and key words: Data processing, Optical fiber devices, Optical fiber sensors, Mechanical sensors, Mechanical variables control, Electric variables control, Digital signal processing, Temperature sensors, Signal design, Microcontrollers. Abstract: In the work the creation of the device of digital signal processing from the fibre-optical sensor of mechanical values is featured. The device allows to spend measurements and to produce adjustment of the sensor remotely and with a big degree of accuracy. The device connects to a PC on a three-wire line of link with usage of the standard transfer protocol of data RS-232C. The scheme is implemented with usage of chips of corporations Atmel (AT90S2313), Analog Devices (AD7705), Texas Instruments (TLV56I4) and Intersil (HIN202CP). |
6,809 | Please write an abstract with title: Transient Analysis of Vehicle-to-Grid Systems Incorporating Plug-in Electric Vehicles, and key words: Vehicle-to-grid, Power system stability, Load management, Stability analysis, State of charge, Reliability, Transient analysis. Abstract: Vehicle-to-grid (V2G) systems are being considered as complementary sources for peak shaving and load levelling on traditional power grids. However, the harmonics and transients associated with this technology may threaten utility grid power quality, stability and equipment reliability. In this study, the transient behavior of a V2G system under varying grid and vehicle load conditions is examined using a test system. Bidirectional converter transient behavior is simulated to predict the relationship between V2G load variations and associated transients. Potential applications of this test system include the prediction of grid conditions that could lead to equipment failure, and the design and evaluation of equipment protection for V2G systems. |
6,810 | Please write an abstract with title: Distributed multirobot localization, and key words: Robot sensing systems, Robot kinematics, Information filters, Information filtering, Mobile robots, Magnetic field measurement, Working environment noise, Computer science, Magnetic sensors, Area measurement. Abstract: In this paper, we present a new approach to the problem of simultaneously localizing a group of mobile robots capable of sensing one another. Each of the robots collects sensor data regarding its own motion and shares this information with the rest of the team during the update cycles. A single estimator, in the form of a Kalman filter, processes the available positioning information from all the members of the team and produces a pose estimate for every one of them. The equations for this centralized estimator can be written in a decentralized form, therefore allowing this single Kalman filter to be decomposed into a number of smaller communicating filters. Each of these filters processes the sensor data collected by its host robot. Exchange of information between the individual filters is necessary only when two robots detect each other and measure their relative pose. The resulting decentralized estimation schema, which we call collective localization, constitutes a unique means for fusing measurements collected from a variety of sensors with minimal communication and processing requirements. The distributed localization algorithm is applied to a group of three robots and the improvement in localization accuracy is presented. Finally, a comparison to the equivalent decentralized information filter is provided. |
6,811 | Please write an abstract with title: Efficient and Robust Line-based Registration Algorithm for Robot Perception Under Large-scale Structural Scenes, and key words: Three-dimensional displays, Runtime, Mechatronics, Conferences, Robustness, Complexity theory, Robots. Abstract: Point cloud registration is a classical problem in advanced robot perception. Despite having been widely studied, the registration of large-scale point clouds still remains challenging in terms of both efficiency and accuracy. In this paper, aiming at the registration in large-scale structural scenes that contains numerous line-features, we propose a line-based efficient and robust registration algorithm for robot perception. Concretely, we first extract lines from point clouds and use the line-features to perform the registration, which decreases the scale of algorithm’s input and decouples the rotation and the translation sub-problems. Consequently, it reduces the complexity of registration problem. We then solve the rotation and translation sub-problems using the branch-and-bound algorithm, which ensures the accuracy and robustness of registration. In translation sub-problem, we propose two strategies to adapt to the registration problem in different scenes, the one is universal algorithm, the other is decoupled algorithm. Extensive experiments are performed on both synthetic and real-world data to demonstrate the advantages of our method. |
6,812 | Please write an abstract with title: Mathematical Models for Calculation of Limits in Water Resources Management in Irrigation Systems, and key words: Irrigation, Information science, Process control, Information security, Mathematical models, Communications technology, Personnel. Abstract: In the present article, algorithms for calculating limits in water resources management in irrigation systems were carried out and the problems of water resources management of the Basin Irrigation Systems Administration which were studied is characterized by the fact that it is necessary to solve the problems of collecting and processing information about the control object from large territories and to manage its links, which are located at large distances from each other. |
6,813 | Please write an abstract with title: Eigenmode analysis of optical propagation in large-scale subwavelength periodic nanostructures, and key words: Optical propagation, Large-scale systems, Nanostructures, Optical materials, Optical refraction, Optical harmonic generation, Optical computing, Optical design, Optical devices, Gratings. Abstract: Summary form only given. We describe a method for rigorously computing the mode characteristics of a periodic nanostructure, and its application to the accurate design of composite optical materials and novel optical devices. In a form-birefringent nanostructure such as a 1D subwavelength periodic grating, the different field distributions for the two linear polarizations result in different effective indices of refraction. Thus the effective optical properties may be engineered through the structure geometry and choice of constituent materials. Engineering of the propagation characteristics of the eigenmodes in a nanostructure can also be used to realize novel photonic devices, such as to achieve phase matching for second harmonic generation (SHG). |
6,814 | Please write an abstract with title: DISTATIS: The Analysis of Multiple Distance Matrices, and key words: Multidimensional systems, Face recognition, Aggregates, Humans, Object recognition, Performance evaluation, Testing, Cognition, Neuroscience, Time measurement. Abstract: In this paper we present a generalization of classical multidimensional scaling called DISTATIS which is a new method that can be used to compare algorithms when their outputs consist of distance matrices computed on the same set of objects. The method first evaluates the similarity between algorithms using a coefficient called the RV coefficient. From this analysis, a compromise matrix is computed which represents the best aggregate of the original matrices. In order to evaluate the differences between algorithms, the original distance matrices are then projected onto the compromise. We illustrate this method with a "toy example" in which four different "algorithms" (two computer programs and two sets of human observers) evaluate the similarity among faces. |
6,815 | Please write an abstract with title: GRIP: a reconfigurable architecture for host-based gigabit-rate packet processing, and key words: Reconfigurable architectures, Network interfaces, Prototypes, Computer networks, Cryptography, Application software, Military computing, Bandwidth, Protocols, Computer interfaces. Abstract: One of the fundamental challenges for modern high-performance network interfaces is the processing capabilities required to process packets at high speeds. Simply transmitting or receiving data at gigabit speeds fully utilizes the CPU on a standard workstation. Any processing that must be done to the data, whether at the application layer or the network layer, decreases the achievable throughput. This paper presents an architecture for offloading a significant portion of the network, processing from the host CPU onto the network interface. A prototype, called the GRIP (Gigabit Rate IPSec) card, has been constructed based on an FPGA coupled with a commodity Gigabit Ethernet MAC. Experimental results based on the prototype are presented and analyzed. In addition, a second generation design is presented in the context of lessons learned from the prototype. |
6,816 | Please write an abstract with title: Modeling of liquid desiccant cooling and dehumidification system based on artificial neural network, and key words: Atmospheric modeling, Heat transfer, Predictive models, Cooling, Heat recovery, Data models, Neural networks. Abstract: Liquid desiccant dehumidification system (LDDS) has emerged as an energy-efficient approach for air dehumidification. In this paper, a simple model for the liquid desiccant cooling and dehumidification air conditioning (LDCDAC) system is proposed. The model is built by using artificial neural network (ANN) to describe the cooling, dehumidification and regeneration performance of the LDCDAC system. The system outlet parameters, such as chilled water temperature, air temperature and humidity, can be calculated directly from the inlet parameters. A multilayer neural network is adopted, and the ANN model is trained by the experimental data collected under different operating conditions. The model predictions of the heat and mass transfer rates are compared with the experimental values. The results indicate that the model predicting errors are within ±8%. The proposed model can be used in control and optimization applications of the LDCDAC system. |
6,817 | Please write an abstract with title: A Study on Specific Emitter Identification Using Modified Allan Variance and Correlation Coefficient, and key words: Correlation coefficient, Wireless communication, Wireless sensor networks, Receivers, Fingerprint recognition, Security, Communication system security. Abstract: With the development of information technology, security issues have also emerged. This work finds out the electronic fingerprints of wireless devices in the field of specific emitter identification (SEI). In this study, signals of each wireless communication device are received and and Allan variance is employed to calculate the standard deviation. Then we check whether a specific individual device can be distinguished from the same type of wireless communication device by using the Pearson correlation coefficient. |
6,818 | Please write an abstract with title: Compliant mooring technology to separate buoy motion from in-line current meter observations, and key words: Sea surface, Instruments, Current measurement, Surface waves, Sea measurements, Acceleration, Water, Accelerometers, Monitoring, Telemetry. Abstract: To separate buoy motion effects from current meters and other sensors on the mooring line, compliant elastic elements have been used in the mooring directly under the buoy. This approach was used in the Massachusetts Bays Program to separate surface buoy motion from VACM current meters below. the elastic elements. Recently a mooring designed to measure waves with a surface following buoy was instrumented with an ADCP and water property sensors. Compliant elastic elements were used at the top of the mooring to allow the buoy to move freely with the waves without having to accelerate the mooring and deeper instrumentation. An ADCP was mounted near the bottom in an upward looking configuration. 0.5 kN of additional flotation (120 lbf) at the bottom of the elastic elements kept the lower part of the mooring taut to minimize motion. The elastic elements provided about 1.3 kN (300 lbf.) of mooring pretension, and, depending on the horizontal current and the wave activity, the tension at the buoy could rise to about 3.5 kN (800 lbf.). Computer modeling of the mooring showed no vertical and minimum horizontal motion in the lower part of the mooring and reasonable tensions that would allow the buoy to follow the waves. Data from the accelerometer in the buoy, the SeaCats in-line and ADCP near the bottom were of high quality. The mooring was recovered by releasing a float from mid-depth that brought a line to the surface from below the elastic elements to allow the mooring (with sensors) and anchor to be retrieved. |
6,819 | Please write an abstract with title: DoD Reconfigurable Antennas, and key words: Antennas, US Department of Defense, Antenna arrays, Aircraft navigation, Aircraft, Wires, Pulse measurements. Abstract: The DoD utilizes many reconfigurable antennas for various purposes. The most prevalent reason is when pattern scanning is necessary. The tactical air navigation system (TACAN) is a navigation system used by military aircraft. The most basic TACAN antenna is composed of a cylindrical nested array. Ballistic missile detection utilizing phased array radars is one of the earliest applications of pattern reconfigurable antennas. The Sea‐Based X‐band radar is unique in that it is semiportable and the largest and most sophisticated X‐band phased array radar in the world. The goal of advanced multifunction RF concept was to develop one system that could simultaneously support multiple functions through a set of shared assets including the antenna aperture. The vision for integrated topside was to provide Navy platforms with adaptable RF capabilities at reduced cost by developing integrated sensors and communication solutions which are open, modular, and scalable. |
6,820 | Please write an abstract with title: Ionospheric perturbation associated with earthquakes, as revealed from subionospheric VLF/LF propagation, and key words: Earthquakes, Electromagnetic coupling, Seismic measurements, Ionosphere, Tellurium, Space technology, Remote sensing, Electromagnetic propagation, Satellite broadcasting, Electromagnetic fields. Abstract: NASDA (National Space Development Agency of Japan) has just finished the Earthquake Remote Sensing Frontier Project conducted since 1996 within the framework of the Earthquake Frontier Projects by the former STA (Science and Technology Agency). The main emphasis of NASDA's Frontier Project was the complete understanding of lithosphere-atmosphere-ionosphere (LAI) coupling by making full use of different kinds of observational items and finally we contribute to the short-term earthquake prediction. The most exciting finding from our Frontier project was the discovery of convincing evidence on the presence of seismo-ionospheric perturbations, which has been extensively investigated by using the subionospheric VLF/LF propagation, and several important findings have been presented, including the initial result for the Kobe earthquake and a few case studies from much data. |
6,821 | Please write an abstract with title: Leaky-wave dispersion behavior on a grounded ferrite slab waveguide, and key words: Ferrites, Slabs, Surface waves, Magnetostatic waves, Electromagnetic waveguides, Magnetic analysis, Cutoff frequency, Integral equations, Optical waveguides, Strips. Abstract: In this letter, leaky-wave dispersion behavior is studied for a grounded biased-ferrite slab waveguide. The full-wave analysis encompasses space-wave leaky modes, surface waves, and magnetostatic modes supported by a ferrite slab as the magnetic bias field varies in strength. In particular, as the bias field increases from a null value the TE leaky-wave cutoff frequencies of the isotropic slab split into two cutoff frequencies, resulting in complicated dispersion behavior of the corresponding forward and backward leaky waves. TM modes are unaffected by variation in the strength of the bias field for this orientation. |
6,822 | Please write an abstract with title: Unlocking Galactic Wolf–Rayet stars with Gaia DR2 – II. Cluster and association membership, and key words: stars: distances, stars: Wolf–Rayet, open clusters and associations: general, galaxies: individual (Milky Way), galaxies: star formation. Abstract: Galactic Wolf–Rayet (WR) star membership of star-forming regions can be used to constrain the formation environments of massive stars. Here, we utilize Gaia DR2 parallaxes and proper motions to reconsider WR star membership of clusters and associations in the Galactic disc, supplemented by recent near-infrared studies of young massive clusters. We find that only 18–36 per cent of 553 WR stars external to the Galactic Centre region are located in clusters, OB associations or obscured star-forming regions, such that at least 64 per cent of the known disc WR population are isolated, in contrast with only 13 per cent of O stars from the Galactic O star Catalogue. The fraction located in clusters, OB associations or star-forming regions rises to 25–41 per cent from a global census of 663 WR stars including the Galactic Centre region. We use simulations to explore the formation processes of isolated WR stars. Neither runaways, nor low-mass clusters, are numerous enough to account for the low cluster membership fraction. Rapid cluster dissolution is excluded as mass segregation ensures WR stars remain in dense, well-populated environments. Only low-density environments consistently produce WR stars that appeared to be isolated during the WR phase. We therefore conclude that a significant fraction of WR progenitors originate in low-density association-like surroundings which expand over time. We provide distance estimates to clusters and associations host to WR stars, and estimate cluster ages from isochrone fitting. |
6,823 | Please write an abstract with title: Filter Versus Wrapper Feature Selection for Network Intrusion Detection System, and key words: Feature extraction, Intrusion detection, Telecommunication traffic, Computational modeling, Sociology, Statistics, Support vector machines. Abstract: With the increased usage of the Internet, the need for providing security and privacy to protect computer networks is increased too. Network intrusion detection system (NIDS) is intended to observe and inspect the activities in a network. This system is highly dependent on the features of the input network data as these features describe the behaviour of the current network activities. Not only do the irrelevant and redundant network features cause the learning algorithm to build an inaccurate detection model, but they also increase the time complexity and exhaust computation resources as well. In this paper, several feature selection techniques are applied to boost the performance of the NIDS. Categories of the applied selection techniques are of the filter (Information Gain (IG), Principal Component Analysis (PCA), and Correlation Feature Selection (CFS)) and of the wrapper (Genetic Algorithm (GA), Artificial Bee Colony (ABC) and Particle Swarm Optimization (PSO)). Support vector machine (SVM) is utilized to classify the network connections. The benchmark network traffic NSL-KDD dataset is selected to build and test the NIDS. The impact of the applied selection approaches on enhancing the detection model performance is compared and discussed. Evaluation results stated that the wrapper approaches achieved better classification performance for the NIDS in terms of high classification accuracy, detection rate, true positive rates, and low false-positive rates than the filter approaches. Our ABC-NIDS is compared with other related NIDSs and the comparison result proved that our system achieved the best performance. |
6,824 | Please write an abstract with title: Analysis and design of low-distortion CMOS source followers, and key words: Semiconductor device modeling, Equations, Frequency, Linearity, Harmonic analysis, CMOS technology, MOS devices, Transfer functions, Circuits, Harmonic distortion. Abstract: This paper presents the analysis of CMOS technology based nMOS source follower (NSF), pMOS source follower (PSF), and cascade-complementary source follower(CCSF) using a simplified large-signal model. Three new large-signal second harmonic equations and high-frequency transfer functions are derived. Optimization strategies which permit optimal design for low-distortion NSF, PSF, and CCSF are proposed. This includes a new complementary linearization method introduced for CCSF. With employment of dedicated optimization, the CCSF can achieve significantly better low-distortion broad-band characteristics than the other schemes. Comparative HSPICE simulated results for the three source followers have shown good agreement with the second-order analytical results using the simplified BSIM3 model equations. |
6,825 | Please write an abstract with title: A Wearable Haptic System for Rehabilitation based on the Asymmetric Vibration, and key words: Vibrations, Sensitivity, Senior citizens, System integration, Haptic interfaces. Abstract: To provide better guidance for patients or the elderly during the self-rehabilitation, a haptic system based on the asymmetric vibration was proposed. Due to the Non-linearity of Perception asymmetric vibration periodic movement can provide a sense of pushing and pulling. In order to better support human motion, we evaluated the sensitivity of different parts of the human body to this haptic assist. And by combining with the gyro-sensor through the contrast experiment, we compared the accuracy of motion learning with or without the haptic assist. The results of three subjects showed that the accuracy of motion learning was improved compared to without haptic assist. Therefore, the system has great potential in the guidance of patients' self-rehabilitation. |
6,826 | Please write an abstract with title: Could IEEE 802.11bc Enhance Data Broadcast Performance for Moving Station: A Frame Loss Perspective, and key words: Wireless communication, Analytical models, Vehicular and wireless technologies, Focusing, Authentication, Handover, Downlink. Abstract: IEEE 802.11bc is especially designed for enhancing the broadcast performance in wireless local network. Focusing on improving the broadcast data frame scheduling and origin authenticity performance, the broadcast data frame scheduling scheme is completely re-designed and the data origin authenticity is introduced in the IEEE 802.11bc. However, after introducing these updated mechanisms, the data broadcast performance due to station mobility, especially during the handover period, remains un-explored. Motivated by this, in this paper, we investigate the downlink handover broadcast data frame loss rate in the IEEE 802.11bc. With special focus on the updated broadcast data frame scheduling and data authentication in the IEEE 802.11bc, we derive an analytical model for the downlink broadcast frame loss rate. Based on the analytical model and simulation test, we give the broadcast parameters configuration for the specified average broadcast data frame loss rate constraint. |
6,827 | Please write an abstract with title: Adaptive Label-Constrained Correlation Filter for UAV Tracking, and key words: Degradation, Information science, Correlation, Target tracking, Adaptive filters, Filtering algorithms, Autonomous aerial vehicles. Abstract: Traditional discriminative correlation filter (DCF) tracking algorithms always use ideal Gaussian functions as labels to train filters, which has reached promising performance in usual scenarios. However, due to challenges such as camera motion, occlusion and similar targets appearing frequently in unmanned aerial vehicle (UAV) tracking scenarios, these trackers using the identical and fixed labels often lead to over-fitting and model degradation and therefore perform poorly in UAV tracking. Accordingly, we present a new framework named Adaptive Label-Constrained Correlation Filter (LCCF) to adaptively construct a more realistic label function for each frame. Specifically, we propose adaptive label constrain regularization terms to assist in the construction of the desired realistic label function. In addition, we introduce an additional temporal regularization term to ensure the temporal consistency, thus avoiding using an additional fixed learning rate. Broad tests on multiple challenging UAV datasets have strongly established the comparative advantage of LCCF over deep and DCF methods. Moreover, LCCF fulfills the real-time tracking requirements with a tracking speed of 43 FPS. Remarkably, our approach delivers new best performance on VisDrone. |
6,828 | Please write an abstract with title: Stereo matching with linear superposition of layers, and key words: Layout, Optical reflection, Optical scattering, Polarization, Iterative algorithms, Cameras, Atmospheric modeling, Optical computing, Surveillance, Focusing. Abstract: In this paper, we address stereo matching in the presence of a class of non-Lambertian effects, where image formation can be modeled as the additive superposition of layers at different depths. The presence of such effects makes it impossible for traditional stereo vision algorithms to recover depths using direct color matching-based methods. We develop several techniques to estimate both depths and colors of the component layers. Depth hypotheses are enumerated in pairs, one from each layer, in a nested plane sweep. For each pair of depth hypotheses, matching is accomplished using spatial-temporal differencing. We then use graph cut optimization to solve for the depths of both layers. This is followed by an iterative color update algorithm which we proved to be convergent. Our algorithm recovers depth and color estimates for both synthetic and real image sequences. |
6,829 | Please write an abstract with title: A Democratically Collaborative Learning Scheme for Fog-enabled Pervasive Environments, and key words: Peer-to-peer computing, Data models, Training, Trajectory, Machine learning, Computational modeling, Collaborative work. Abstract: The emergence of fog computing has brought unprecedented opportunities to many fields, and it is now feasible to incorporate deep learning at the edge to facilitate the development of pervasive systems (e.g., autonomous driving and smart grids). In this paper, we present our preliminary research on a democratic learning scheme so that fog nodes could collaborate on the model training process even without the support of the cloud, which is urgently needed in the pervasive computing context. The main objective of this work is to utilize the deployed fog nodes to train a well-performed deep learning model together, even with the limited local data from each participant. Instead of relying on the cloud by default, we design a voting strategy so that a fog node could be elected as the coordinator based on both distance and computational power metrics to help expedite the training process. We then experiment the effectiveness of the scheme through a real-world, in-door fog deployment and verify the performance of the trained model through a human moving trajectory tracking use case. |
6,830 | Please write an abstract with title: Guaranteed Trade-Offs in Dynamic Information Flow Tracking Games, and key words: Heuristic algorithms, Conferences, Stochastic processes, Games, Approximation algorithms, Picture archiving and communication systems, Security. Abstract: We consider security risks in the form of advanced persistent threats (APTs) and their detection using dynamic information flow tracking (DIFT). We model the tracking and the detection as a stochastic game between the attacker and the defender. Compared to the state of the art, our approach applies to a wider set of scenarios with arbitrary (not only acyclic) information-flow structure. Moreover, multidimensional rewards allow us to formulate and answer questions related to trade-offs between resource efficiency of the tracking and efficacy of the detection. Finally, our algorithm provides results with probably approximately correct (PAC) guarantees, in contrast to previous (possibly arbitrarily imprecise) learning-based approaches. |
6,831 | Please write an abstract with title: Design of Multimedia Assisted English online teaching model based on flipped classroom, and key words: Analytical models, Distance learning, Education, Online services, Reliability, Prognostics and health management. Abstract: Aiming at the current information needs of English learning, combined with the current problems of multimedia-assisted teaching, a multimedia-assisted English online teaching model based on flipped classrooms is designed. Analyze the characteristics of multimedia-assisted English online teaching and optimize the functions of the teaching model; based on the dual-agent teaching theory of flipped classroom English teaching, the model’s login module and personalized recommendation module are designed with emphasis on the online assisted teaching function optimize management. Experimental results show that after using this model, the accuracy of classroom exercises has been effectively improved, indicating that it can provide a reference for the application of intelligent recommendation algorithms in English teaching. |
6,832 | Please write an abstract with title: Design and Optimization of Permanent Magnet Synchronous Motor for Electric Vehicle Applications, and key words: Magnetic flux, Permanent magnet motors, Synchronous motors, Electric vehicles, Magnetic analysis, Torque measurement, Optimization. Abstract: In this study, the design of 50kW permanent magnet synchronous motor (PMSM) for electric vehicle applications is presented. In the design process, initially, main design constraints and requirements for electric vehicle are determined and the main dimensions of the machine are calculated. In order to investigate electromagnetic and operational performances of motor, motor design program based on finite element method was used and the motor is analyzed. Then, size and position of magnets which are effective in the performance of PMSM are optimized and compared with a conventional machine. |
6,833 | Please write an abstract with title: Research on A Position Servo Control Method of Aircraft Cargo Door Based on PMSM, and key words: Magnetic separation, Adaptive filters, Filtering algorithms, Planning, Servosystems, Aircraft, Aerospace control. Abstract: In this paper, a three-loops position servo control method of a permanent magnet synchronous motor (PMSM) for a large aircraft cargo door actuator system (CDAS) is designed to improve the fastness and robustness of the system.First, an adaptive filter is designed, and the weight of the filter is adjusted by a normalized minimum mean square (NLMS) filter algorithm, so that the transfer function of the filter is approximately equivalent to the inverse model of the current loop of the controlled motor, and the output of the filter is used as compensation of torque feedforward to reduce the impact of external load disturbances on the system. Because it does not rely on the error of the controlled variable, the feedforward control can quickly compensate for external disturbances. Thus, it can effectively improve the fastness and robustness of the electromechanical actuation system of the cargo door.In addition, an algorithm based on trigonometric function for position curve and speed curve planning is designed. The position planning curve is used as the input of the position loop, and the speed planning curve and the controller output of the position loop are used as the input of the speed loop. Compared with the piecewise S-curve function as the position planning and speed planning curve, this method has better tracking effect, smaller overshoot and tracking error, and smaller peak phase current. Simulation results verify the effectiveness of the method. |
6,834 | Please write an abstract with title: Three-dimensional Frequency Selective Surface with Quasi-elliptic Bandpass Response, and key words: Frequency selective surfaces, Resonant frequency, Stripline, Bandwidth, Electromagnetic waveguides, Photonics. Abstract: A novel three-dimensional (3-D) frequency selective surface (FSS) exhibiting wide- band and highly selective bandpass response is presented. The proposed FSS consists of a two- dimensional periodic array of vertical, shielded, and suspended striplines. By combining the high- pass property of the periodic array of waveguides with bandstop resonances from the inserted U-shaped striplines, a quasi-elliptic bandpass frequency response over a wide-band from 8.4 GHz to 16.2 GHz is achieved with a 3 dB frequency bandwidth of 63% and a sharp rejection skirt. |
6,835 | Please write an abstract with title: Highly reliable 40 mW, 25 GHz × 20 ch thermally tunable DFB laser module integrated with wavelength monitor, and key words: Tunable circuits and devices, Monitoring, Wavelength division multiplexing, Laser stability, Packaging, Optical control, Power generation, Temperature, Photonics, Laser beams. Abstract: We developed a thermally tunable DFB laser module integrated with a wavelength monitor. We achieved PMF coupled power > 40mW, 25GHz × 20 ch tunabily, extremely small wavelength drift < +/-1 25GHz and lower TEC power consumption < 5W with very promising aging data. |
6,836 | Please write an abstract with title: The influence of interparticle forces in the magnetic separation of submicron particles, and key words: Magnetic separation, Potential energy, Solids, Saturation magnetization, Optical fiber theory, Equations, Potential well, Filtration, Steady-state, Magnetic levitation. Abstract: The magnetic separation of ultrafine particles is described in terms of a number of particle - particle - fibre interactions some of which are important only in this size regime. Conditions for solid and diffuse buildup are established in terms of the total potential energy of a particle. The detailed form of the buildup is shown to be strongly dependent on the surface potential of particles and, consequently, the pH of the colloid. The calculated results are found to compare favourably with diffusion theory. The initial rate of particle capture is shown to be a quadratic function of time. |
6,837 | Please write an abstract with title: Analysis and implementation of an active clamp ZVS forward converter, and key words: Clamps, Zero voltage switching, Rectifiers, Switches, Switching converters, RLC circuits, Switching circuits, Circuit analysis, Stress, Capacitors. Abstract: The system analysis and circuit implementation of ZVS forward converter with center-tapped rectifier are presented in this paper. To reduce the voltage stress of active switch in the forward converter, one auxiliary switch and one clamp capacitor are used in the adopted converter to recycle the energy stored in the transformer leakage. The resonant circuit based on the output capacitance of switches and leakage inductance of the transformer achieves zero voltage switching turn-on for both switches in the adopted converter to increase the total circuit efficiency. The center-tapped rectifier is used at the secondary side to achieve full-wave rectifier. In the high output current applications, the synchronous rectifier can be used in the secondary side to further reduce the conduction losses of rectifier diodes. The operation principles of the adopted ZVS forward converter with center-tapped rectifier are analyzed in detail. The design consideration and circuit example of ZVS forward converter are presented. Finally experimental results based on a ZVS forward converter with 5 V/16 A output load are provided to verify the effectiveness of the adopted converter |
6,838 | Please write an abstract with title: Block approach for CSTR Control, and key words: Chemical reactors, Inductors, Mathematical model, Observers, Perturbation methods, Coolants, Automation. Abstract: The article deals with the problem of synthesis of control, providing temperature maintenance in the jacket of the CSTR reactor. The standard mathematical model, describing the reactor operation, has been extended by introducing the following dynamics of the executive device and consideration of physical restrictions of the state and control vector components. Under conditions of incomplete information about the state vector and at influence of external disturbances, an observer of the state and disturbances is synthesized, allowing to receive estimations of unknown signals with the set accuracy. The use of the block approach allowed to take into account physical constraints on phase variables and control at the stage of feedback synthesis. The proposed approach showed high efficiency by modeling the system CSTR reactor - DC motor in the Matlab simulation experiment. |
6,839 | Please write an abstract with title: Texture-based characterization of urban environments on satellite SAR images, and key words: Satellites, Urban areas, Cities and towns, Costs, Sensor phenomena and characterization, Synthetic aperture radar, Density measurement, Buildings, Image analysis, Information analysis. Abstract: We investigate the use of co-occurrence texture measures to provide information on different building densities inside a town structure. We try to improve the pixel-by-pixel classification of an urban area by considering texture measures as a means for block analysis and classification. We find some interesting hints concerning the optimal dimension of the window to be considered for texture measures, as well as the most useful measures. Moreover, we show that it is possible to use medium-resolution readily available satellite synthetic aperture radar images for a more refined urban analysis than previously shown. |
6,840 | Please write an abstract with title: Wireless IP adaptation layer: an open performance enhancement protocol architecture, and key words: Wireless application protocol, Access protocols, TCPIP, Quality of service, Boosting, Adaptive systems, Forward error correction, Wireless communication, Production, IP networks. Abstract: Heterogeneous networks require mechanisms for transparent protocol boosting in legacy systems and adaptive support for seamless interoperability between different wireless access methods. In this paper, we present an open performance enhancement protocol architecture that is developed to provide a generic protocol enhancing proxy (PEP) service for wireless access points and terminals. First, we describe the basic architecture and philosophy of our approach. Then some illustrative protocol boosting modules are presented with results. Finally, we describe the future work that is required in order to make the so-called wireless adaptation layer (WAL) useful in production quality environments. |
6,841 | Please write an abstract with title: Congestion management: The system operators challenge to balance transmission transfer capacity with an acceptable security level, and key words: Power system security, Environmental management, Pricing, Globalization, Standards publication. Abstract: The paper discusses the challenges and possible solutions to balance the increasing need of transfer capacity with an acceptable security level. The liberalised market system calls for flexibility in power exchanges to enhance the competition at the same time as there is an increasing need for someone to supervise the overall system operation. Operating the power system closer to technical limits makes it necessary to have efficient methods to deal with cases with insufficient transfer capacity. Major techniques discussed in this paper to handle this are the market splitting, locational marginal pricing and the recently proposed flow-based market coupling. Basic principles, possibilities and limitations of these techniques as well as suitable instruments to mitigate the limitations are addressed. A discussion of which market models these techniques are suitable for, is included. The paper further discusses the aspects related to defining appropriate transfer levels under different security criteria and the possibility to make corrective actions during emergencies. Moving from a preventively secure system operation to a correctable secure operation will significantly increase the transfer capacities and give the market some of the requested capacity, but at some risk for disconnection of loads and components |
6,842 | Please write an abstract with title: Secure Link Selection for Relay Networks with Buffer, and key words: Wireless communication, Closed-form solutions, Stationary state, Relay networks (telecommunication), Probability, Markov processes, Power system reliability. Abstract: Buffer-aided relay technique can improve the diversity order and offer secrecy provision. To further improve secrecy performance, this paper proposes a secure link selection for relay networks where a new link selection policy is first designed under the constraint on the buffers and channel states using a Markov chain. The stationary state and the corresponding state transition matrix can be derived, and they are used to analyze the secrecy performance. Through the derivation of secrecy outage probability, we can get its closed-form expressions. Numerical results demonstrate that the proposed secure transmission scheme has a better performance than the conventional buffer-aided secure transmission schemes in terms of secrecy outage probability. |
6,843 | Please write an abstract with title: The role of pulse repetition frequency in ultrasonic contrast agent stability and cell death, and key words: Frequency, Stability, Ultrasonic imaging, Cells (biology), Acoustic scattering, Acoustic pulses, Mice, Ultrasonic transducers, Ultrasonic variables measurement, Acoustic beams. Abstract: Ultrasound exposure of phagocytic cells with contrast agent microbubbles attached can cause cell death. The influence of pulse repetition frequency (PRF) on the occurrence of such cell death was studied. Phagocytic cells of mouse macrophage cell line RAW-264.7 were grown as monolayers on thin Mylar sheets by standard culture methods. These cells retain contrast agent when incubated with 5% Optison/sup /spl reg// (Amersham Health, Princeton NJ) for 15 minutes and then rinsed to remove unattached microbubbles. A sealed chamber was formed with a second thin sheet placed 1 mm from the first sheet containing cells. Focused ultrasound exposures were implemented at a frequency of 2.25 MHz with 46 cycle pulses and PRF's of 1 kHz, 100 Hz, 10 Hz, 1 Hz, and 0.1 Hz. All ultrasound exposures were performed with a peak rarefactional pressure of 2 MPa in a degassed water bath. A 1 MHz receiver transducer measured the scattered signal from the monolayer containing cells and contrast agent. The signals were captured using a high speed digitizing board and range gated from within the chamber. The frequency spectrum was then computed and normalized to a control spectrum from linear scatterers (Zerdine/sup TM/, CIRS, Norfolk, VA). Photomicrographs of the cell monolayer were made in the ultrasound beam area before and after exposure, and a dye exclusion test (Trypan Blue) was used to find the percentage of blue stained cells indicating loss of cell membrane integrity and cell death. Cell death (counted as both the absent and stained cells) was examined and related to acoustic emission. Acoustic scattering power was higher for Pulse #1 than that for Pulse #2. For 5% Optison/sup /spl reg//, cell death at 1 kHz PRF was lower that that for 100 Hz, 10 Hz, 1 Hz, 0.1 Hz. |
6,844 | Please write an abstract with title: Extended hybrid statistical tools ANFIS- GA to optimize underwater friction stir welding process parameters for ultimate tensile strength amelioration, and key words: Welding, Friction, Velocity control, Artificial neural networks, Tools, Predictive models, Three-dimensional printing. Abstract: The qualities of functional parts produced by underwater friction stir welding (UWFSW) with additive water are significantly reliant on standard FSW process parameters. To improve the goal function, hybrid statistical tools can be used to optimize operation parameters. This work investigates the tensile strength(σUTS) of tests ASTM D638-14 specified parts manufactured using UWFSW by Al AA 6063-T6 material. Three parameters were varied in the fabrication of test specimens: speed of rotation from 1000 to 1800 rpm, speed of traveling from 4 to 10 mm/s, and shoulder diameter from 10 to 20 mm. Using a Hybrid artificial neural network- genetic algorithm (ANN-GA) and Hybrid artificial neural network-fuzzy-genetic algorithm (ANFIS-GA). The ANFIS-GA achieved the highest precision of 98.99 %, resulting in optimum parameters like rotational speed 1800 rpm, travelling speed 4 mm/s, and shoulder diameter 15 mm to produce a maximum tensile strength of 266 MPa. The hybrid models developed could be used to predict and maximize specific process parameters and impacts for a variety of industrial situations. |
6,845 | Please write an abstract with title: Stochastic Analysis of Regenerative Braking Energy of Urban Transportation System Associated with Plug-in Electrical Vehicle in Smart City, and key words: Plug-in electric vehicles, Vehicle-to-grid, Uncertainty, Smart cities, Simulation, Stochastic processes, Microgrids. Abstract: Existing distribution systems have had to adapt in response to improving for better-supporting consumers in smart cities. This digest focuses on optimal operation control strategies considering plug-in electric vehicles (PEVs) and subway systems. In this digest, linear programming is proposed for the optimization algorithm by applying regenerative braking energy (RBE). The proposed problem optimizes the energy's total cost considering both vehicles to grid (V2G) and vehicle to subway (V2S) technology. Besides, a stochastic framework is used to model the uncertainty of PEVs, load, and distributed energy resources (DERs). The feasibility of the proposed method is examined in a fictional smart city. |
6,846 | Please write an abstract with title: Coupled tunnel junction experiments at the gap frequency, and key words: Voltage, Niobium, Local oscillators, Electrodes, Frequency measurement, Counting circuits, Signal generators, Voltage-controlled oscillators, Fabrication, Coupling circuits. Abstract: By using a capacitively coupled set of Josephson tunnel junctions we have performed experiments on the feasibility of using a Josephson junction as a local oscillator at frequencies up to and in excess of the gap sum of the junction. One junction was biased to serve as a local oscillator, whose AC power output could be monitored by observing the constant voltage Josephson steps on the current-voltage characteristic of the second junction. Using this coupling scheme we have coupled large oscillator signal levels (∼ 12.5nW) into the detector junction. For frequencies below the gap sum frequency our measurements are consistent with the Werthamer theory. For bias voltages above the gap sum we observe an anomalously fast roll off of the detected power from the oscillator junction. |
6,847 | Please write an abstract with title: Deep Reinforcement Learning in a Racket Sport for Player Evaluation With Technical and Tactical Contexts, and key words: Sports, Games, Videos, Reinforcement learning, Markov processes, Task analysis, Feature extraction. Abstract: Evaluating the performance of players in a dynamic competition is vital for achieving effective sports coaching. However, a quantitative evaluation of players in racket sports is difficult because it is derived from the integration of complex tactical and technical (i.e., whole-body movement) performances. In this study, we propose a new evaluation method for racket sports based on deep reinforcement learning, which can analyze the motion of a player in more detail, rather than only considering the results (i.e., scores). Our method uses historical data including information related to the tactical and technical performance of players to learn the next-score probability as a Q-function, which is used to value the actions of the players. We leverages long short-term memory model for the learning of Q-function with the poses of the players and the position of the shuttlecock as the input, which are identified by the AlphaPose and TrackNet algorithms, respectively. We verified our approach by comparing various baselines and demonstrated the effectiveness of our method through use cases that analyze the performance of the top badminton players in world-class events. |
6,848 | Please write an abstract with title: Deep Compressive Sensing for Visual Privacy Protection in FlatCam Imaging, and key words: Image reconstruction, Visualization, Cameras, Privacy, Convolution, Software. Abstract: Detection followed by projection in conventional privacy cameras is vulnerable to software attacks that threaten to expose image sensor data. By multiplexing the incoming light with a coded mask, a FlatCam camera removes the spatial correlation and captures visually protected images. However, FlatCam imaging suffers from poor reconstruction quality and pays no attention to the privacy of visual information. In this paper, we propose a deep learning-based compressive sensing approach to reconstruct and protect sensitive regions from secured FlatCam measurements. We predict sensitive regions via facial segmentation and separate them from the captured measurements. Our deep compressive sensing network was trained with simulated data, and was tested on both simulated and real FlatCam data. |
6,849 | Please write an abstract with title: Online Recognition of Bimanual Coordination Provides Important Context for Movement Data in Bimanual Teleoperated Robots, and key words: Training, Performance evaluation, Three-dimensional displays, Robot kinematics, Surgery, Robot sensing systems, Needles. Abstract: An important problem in designing human-robot systems is the integration of human intent and performance in the robotic control loop, especially during complex tasks. Bimanual coordination is a complex human behavior that is critical in many fine motor tasks, including robot-assisted surgery. To fully leverage the capabilities of the robot as an intelligent and assistive agent, online recognition of bimanual coordination could be important. Robotic assistance for a suturing task, for example, will be fundamentally different during phases when the suture is wrapped around the instrument (i.e., making a c-loop), than when the ends of the suture are pulled apart. In this study, we develop an online recognition method of bimanual coordination modes (i.e., the directions and symmetries of right and left hand movements) using geometric descriptors of hand motion. We (1) develop this framework based on ideal trajectories obtained during virtual 2D bimanual path following tasks performed by human subjects operating Geomagic Touch haptic devices, (2) test the offline recognition accuracy of bimanual direction and symmetry from human subject movement trials, and (3) evalaute how the framework can be used to characterize 3D trajectories of the da Vinci Surgical System’s surgeon-side manipulators during bimanual surgical training tasks. In the human subject trials, our geometric bimanual movement classification accuracy was 92.3% for movement direction (i.e., hands moving together, parallel, or away) and 86.0% for symmetry (e.g., mirror or point symmetry). We also show that this approach can be used for online classification of different bimanual coordination modes during needle transfer, making a C loop, and suture pulling gestures on the da Vinci system, with results matching the expected modes. Finally, we discuss how these online estimates are sensitive to task environment factors and surgeon expertise, and thus inspire future work that could leverage adaptive control strategies to enhance user skill during robot-assisted surgery. |
6,850 | Please write an abstract with title: Transmit array processing for cyclic-prefix CDMA, and key words: Array signal processing, Multiaccess communication, MIMO, Receiving antennas, Transmitting antennas, Modulation coding, Delay, Laboratories, Antenna arrays, Frequency domain analysis. Abstract: This paper explores the addition of frequency-domain transmit antenna arrays to the cyclic-prefix CDMA (CP-CDMA) system concept. CP-CDMA is a novel type of single carrier DS-CDMA that employs OFDM-style cyclic prefixes to facilitate efficient frequency-domain receiver processing in broadband CDMA cellular systems. CP-CDMA is intended for high-bandwidth, high-delay-spread cellular channels, such as those envisioned for systems that evolve from current 3G CDMA standards. This paper examines both single-data stream (i.e., maximal ratio transmission) and multiple data stream (i.e., spatial multiplexing also known as multiple-input, multiple-output or MIMO) techniques for CP-CDMA systems that operate with high code usage and multi-level modulation in broadband high delay-spread channels. In the proposed algorithms, both the transmit and receive array processing is performed completely in the frequency-domain to allow the tracking of frequency-selective MIMO channels. Simulation results are presented to show the efficacy of the proposed methods. |
6,851 | Please write an abstract with title: Autonomous robot navigation based on fuzzy sensor fusion and reinforcement learning, and key words: Robot sensing systems, Navigation, Sensor fusion, Learning, Intelligent robots, Intelligent sensors, Target recognition, Intelligent systems, Fuzzy logic, Working environment noise. Abstract: This paper presents the design and implementation of an autonomous robot navigation system for intelligent target collection in dynamic environments. A feature-based multi-stage fuzzy logic (MSFL) sensor fusion system is developed for target recognition, which is capable of mapping noisy sensor inputs into reliable decisions. The robot exploration and path planning are based on a grid map oriented reinforcement path learning system (GMRPL), which allows for long-term predictions and path adaptation via dynamic interactions with physical environments. In our implementation, the MSFL and GMRPL are integrated into a subsumption architecture for intelligent target-collecting applications. The subsumption architecture is a layered reactive agent structure that enables the robot to implement higher-layer functions including path learning and target recognition regardless of lower-layer functions such as obstacle detection and avoidance. Real-world application using a Khepera robot shows the robustness and flexibility of the developed system in dealing with robotic behavior such as target collecting in an ever-changing physical environment. |
6,852 | Please write an abstract with title: ASTS: Attention-based spectrum truncation synthesis for step frequency signals, and key words: Wireless communication, Frequency synthesizers, Fluctuations, System performance, Radar detection, Radar, Object detection. Abstract: With the development of wireless communication technology, various special pulse waveforms are widely used in radar technology to meet specific requirements. The stepped frequency (SF) signal has properties of low instantaneous band-width, high synthetic bandwidth, and high resolution, which is popular in high-precision target detection. Therefore, researches on SF signals have attracted extensive attention recently. In this paper, we introduced an attention mechanism into spectrum synthesis and finally proposed a novel method called Attention-based Spectrum Truncation Synthesis (ASTS) to solve the problem of energy fluctuation caused by spectrum aliasing and our ASTS method performs better than spectrum superposition synthesis (SSS) algorithm in Peak Sidelobe Ratio (PSLR). Furthermore, we found a noticeable phenomenon in detection caused by a dramatic phase jump happening with the RSF signals when detecting the moving targets. Through the theoretical analysis, we concluded formulas indicating how we could compensate for this phase jump and make the RSF achieve a similar PSLR performance as the LSF does. |
6,853 | Please write an abstract with title: Flangeless Waveguide Connection Based on Gap Waveguide Technology, and key words: Surface waves, Waveguide components, Air gaps, Prototypes, Gap waveguide, Electromagnetic waveguides, Flanges. Abstract: To reduce the size of traditional waveguide flange, a solution of pluggable flangeless waveguide connection is proposed. Artificial magnetic conductor (AMC) structure is designed surrounding the outer surface of a size-reduced end of a waveguide, called part-A. Another waveguide with stepped transition to an enlarged end is part-B, the inner surface of the enlarged end works as PEC surface. When Part-A is inserted into part-B, a tight flangeless waveguide connection is achieved under proper size conditions. Tiny air gap exists between the PEC and AMC surface, the electromagnetic leakage from the air gap is prevented by band gap of the EBG structure formed by PEC and AMC surface. A Ku-band prototype of the flangeless connection is designed and manufactured, the measured insertion and return loss are better than 0.06dB and 20dB respectively over 10GHz to 15GHz. The sectional size decreases by more than 70% comparing with traditional waveguide flange. |
6,854 | Please write an abstract with title: Honeypot Allocation for Cyber Deception Under Uncertainty, and key words: Games, Resource management, Security, Complexity theory, Monitoring, Reconnaissance, Uncertainty. Abstract: Cyber deception aims to misrepresent the state of the network to mislead the attackers, falsify their reconnaissance conclusions, and deflect them away from their goals. Honeypots serve as decoy devices inside networks that can capture adversaries for monitoring purposes. We propose a two-phase deception approach based on honeypot allocation. In the first phase, we develop a proactive deceptive honeypot allocation policy, the second phase proposes a reactive deception approach that dynamically allocates honeypots according to IDS updates. Considering a practical scenario, the defender partially monitors the adversary’s activities. To this end, we develop our deception approach using a combination of game-theoretic and reinforcement learning models. We cast the problem of reactive deception as a partially observable Markov decision process (POMDP) based on a game-theoretic dynamic model to accommodate the imperfect monitoring of the actions taken by the attacker. We solve this combined partially observable game model using Monte-Carlo tree search to overcome the game model complexity. We give a game-theoretic analysis to explain the attack-defense policies at equilibrium. Finally, we present numerical results to validate the effectiveness of the proposed deception approach. |
6,855 | Please write an abstract with title: Bibliometric Visualisation of Computer Science and COVID-19: A Review and Proposed Method, and key words: COVID-19, Computer science, Systematics, Pandemics, Conferences, Bibliometrics, Data visualization. Abstract: The pandemic of COVID-19 has accelerated significantly, generating great concern throughout the world. As a result, the quantity of articles and journals published on COVID-19 has rapidly increase. However, these publications do not cover bibliometric visualisation sufficiently, particularly in the computer science field. Thus, the purpose of this article is to conduct a brief content review of the websites that offer bibliographic visualisation about COVID-19. Additionally, we propose a new framework for visually representing bibliometric data pertaining to computer science research and COVID-19. We believe that our method for bibliometric visualisation will benefit future research by serving as a guide. It will serve as a way for conducting COVID-19 bibliometric visualisation, in other areas, not limited to the field of computer science. |
6,856 | Please write an abstract with title: Calculation of electromagnetic scattering from a dielectric cylinder using the conjugate gradient method and FFT, and key words: Electromagnetic scattering, Dielectrics, Gradient methods, Integral equations, Engine cylinders, Magnetic anisotropy, Perpendicular magnetic anisotropy, Electric potential, Green's function methods, Nonuniform electric fields. Abstract: The scattering problem of an axially uniform dielectric cylinder is formulated in terms of the electric field integral equation, where the cylinder is of general cross-sectional shape, inhomogeneity, and anisotropy, and the incident field is arbitrary. Using the pulse-function expansion and the point-matching technique, the integral equation is reduced to a system of simultaneous equations. Then, a published procedure for solving the system using the conjugate gradient method and the fast Fourier transform (FFT) is generalized to the case of oblique-incidence scattering. |
6,857 | Please write an abstract with title: Securing Abstention in an Electronic Legislature, and key words: Terrorism, Legislation, Electronic voting, Protection, Educational institutions, Protocols, Electronic government, Nominations and elections, Fungi, Contamination. Abstract: The reasons for developing an electronic legislature (e-legislature) include: an improved legislature, increasing the constituent's access to the legislator, improving participation in government and providing our goverment with a mobile distributed legislature that will be able to continue to meet even in the face of some drastic activity like terrorism. The essence of a legislature is political and consequently its members will certainly act in such a way. Thus one must assume that legislators would take advantage of the lack of physical presence in a legislature if it was not secured. In [IFIP TC6/TC11 Joint Working Conference on Communications and Multimedia Security (CMS'99)], [Verifiable democracy a protocol to secure an Perspectives] an electronic legislation scheme was proposed that secured the government from malicious behavior of legislators. The protocol described in [IFIP TC6/TC11 Joint Working Conference on Communications and Multimedia Security (CMS'99)], [Verifiable democracy a protocol to secure an Perspectives] provided only minimal legislative voting options, to create a realistic e-legislature one must support all likely functions. Most legislatures allow their members to abstain. The process of introducing abstention into an e-legislature can be formative especially in the case when the legislature passes statutes by simple majority. Here we discuss how to secure an e-legislature which supports abstention. |
6,858 | Please write an abstract with title: Efficient query processing on relational data-partitioning index structures, and key words: Query processing, Database systems, Indexes, Navigation, Image databases, Relational databases, Application software, Design automation, Biomedical imaging, Systems biology. Abstract: In contrast to space-partitioning index structures, data-partitioning index structures naturally adapt to the actual data distribution which results in a very good query response behavior. Besides efficient query processing, modern database applications including computer-aided design, medical imaging, or molecular biology require fully-fledged database management systems in order to guarantee industrial-strength. In this paper, we show how we can achieve efficient query processing on data-partitioning index structures within general purpose database systems. We reduce the navigational index traversal cost by using "extended index range scans". If a directory node is "largely" covered by the actual query, the recursive tree traversal for this node can beneficially be replaced by a scan on the leaf level of the index instead of navigating through the directory any longer. On the other hand, for highly selective queries, the index is used as usual. In this paper, we demonstrate the benefits of this idea for spatial collision queries on the relational R-tree. Our experiments with an Oracle9i database system show that our new approach outperforms common index structures and the sequential scan considerably. |
6,859 | Please write an abstract with title: Value of Information in Wireless Sensor Network Applications and the IoT: A Review, and key words: Wireless sensor networks, Sensors, Monitoring, Internet of Things, Sensor phenomena and characterization, Measurement, Systematics. Abstract: Value of Information (VoI) is a concept to assess the usefulness of information for a specific goal, and has in the last decade experienced a growing interest also for Wireless Sensor Network (WSN) applications and the Internet of Things (IoT). By making the value of information explicit in the form of VoI, WSN and IoT applications should be able to better assess which information to spend their constrained resources on. However, the definition of VoI is highly application-dependent, which has led to a fragmented understanding of VoI, and there is a lack of a comprehensive overview. In this structured review, we first categorize application use cases and examine what VoI is used for, and explore the different approaches to defining VoI. We then provide a well-structured and comprehensive discussion of the specific approaches used in the literature to determine VoI, together with examples of use cases. We categorize the different approaches to calculating VoI, describe their properties systematically and distinguish between observed VoI and expected VoI. We also discuss adaptive VoI approaches and point towards future directions within the field. |
6,860 | Please write an abstract with title: Calculation of eddy current loss in axial field permanent-magnet machine with coreless stator, and key words: Stator cores, Eddy currents, Conductors, Magnetic fields, Finite element methods, Magnets, Machine windings, Magnetic cores, Topology, Stator windings. Abstract: This paper presents a hybrid method for the calculation of eddy current loss in coreless stator axial field permanent-magnet (AFPM) machines. The method combines the use of two-dimensional finite element (FE) field analysis and the closed-form eddy loss formula. To account for three-dimensional field effects in an AFPM machine, a multilayer and multislice modeling technique has been devised. Experimental tests are carried out to validate the method. It is shown that the proposed method predicts the eddy current losses of a coreless stator AFPM machine with high accuracy. |
6,861 | Please write an abstract with title: Facial expression recognition based on Gabor wavelet transformation and elastic templates matching, and key words: Face recognition, Image recognition, Feature extraction, Wavelet analysis, Data mining, Lighting, Facial animation, Frequency, Gray-scale, Pixel. Abstract: In order to achieve subject-independent facial expression recognition and obtain robustness against illumination variety and image deformation, facial expression recognition methods based on Gabor wavelet transformation and elastic templates matching are presented in this paper. Firstly, given a still image containing facial expression information, preprocessors are executed. Secondly, Gabor wavelets are adopted to extract expression features. Then the elastic graph for expression features is constructed. Finally, elastic templates matching algorithm is used to recognize facial expression. Experiments show that the expression features can be extracted effectively by Gabor wavelet transformation and high recognition rate can be obtained using elastic templates matching algorithm. |
6,862 | Please write an abstract with title: A Low-cost Active Reflected Wave Canceller for MMC Motor Drive using SiC Devices, and key words: Motor drives, Interference cancellation, Simulation, Modulation, Voltage, Switches, Medium voltage. Abstract: SiC based MMCs have shown great potential for medium voltage motor drives. Although MMC motor drive has smaller dv/dt compared to 2-level motor drive, the rising/falling edge of each voltage step is still high due to fast switching speed of SiC devices, which will lead to reflected wave phenomenon and voltage surge at motor terminal. This paper proposed an active reflected wave canceller featuring low cost for MMC motor drive to solve this issue. A voltage pulse is injected into the system at each rising/falling edge which cancels the reflected voltage. The operation modes are analyzed and different methods with the same principle are also discussed. The simulation results are presented to validate the effectiveness of the proposed method. |
6,863 | Please write an abstract with title: An Efficient Eco-Planner for Autonomous Vehicles With Focus on Passengers Comfort, and key words: Roads, Wheels, Vehicle dynamics, Energy consumption, Traction motors, Torque, Planning. Abstract: Speed planning is one of the tasks that a self-driving vehicle carries out. A complete planner should consider and balance passengers comfort, trip time and energy consumption. This paper proposes a computationally efficient global speed planner for autonomous vehicles that explicitly includes comfort as one of the main objectives. In particular, our approach considers the trip time as a user-specified constraint and optimizes a cost function that accounts for both energy consumption and comfort. Since passenger comfort plays a critical role for self driving vehicle, we propose a comfort model that captures different aspects: planar and vertical accelerations and the contribution of different frequency components. We test the algorithm on a realistic case study and we quantify the trade-off between energy consumption and comfort. |
6,864 | Please write an abstract with title: Adaptive Neural Network Output Feedback Control of Nonlinear Systems with Actuator Saturation, and key words: Adaptive systems, Programmable control, Adaptive control, Neural networks, Output feedback, Nonlinear control systems, Control systems, Nonlinear systems, Actuators, State estimation. Abstract: An indirect adaptive neural network (NN) saturation compensator is presented for a class of nonlinear systems. Output feedback control is considered where only the system output is assumed to be measurable. The imposed actuator saturation is assumed to be unknown and treated as the system input disturbance. A NN-based state observer estimates derivatives of the output and another NN-based feedback controller is inserted into a feedforward path to capture the nonlinearities of the observed system and to cancel the effects of the unknown disturbances and the unknown saturation nonlinearity. The unknown system states identified by the NN observer are inputs of the NN-based controller. Two NNs interact together to achieve the desired performance. Both adaptive, neural network control laws and on line neural net weights tuning rules are rigorously derived based on feedback linearization and Lyapunov approach. The overall robust adaptive scheme guarantees that the states estimation errors, NN weights estimation errors, and output tracking errors are uniformly ultimately bounded. The simulation conducted indicates the proposed scheme can effectively estimate the unknown nonlinear system states and accommodate the unknown actuator constraints. |
6,865 | Please write an abstract with title: A novel index for electrical model's quality evaluation for the Colombian Power System, and key words: Analytical models, Renewable energy sources, Sensitivity, Power measurement, Shape, Shape measurement, Power system dynamics. Abstract: A novel index developed by Colombia's Power System Operator defined for evaluating the quality of the electrical model of the Colombian Power System, is presented. The index integrally evaluates the quality of the models through comparisons in magnitude and shape of electrical variables obtained with the dynamical models with respect to the electrical variables measured on the elements connected in the power system. The related variables are taken from the most relevant buses of the power system using PMUs. This development constitutes a great help for the Colombian Power System regarding the integration of new technologies in the next future such as Battery Energy Systems, Renewable Resources and Distributed Energy Resources. |
6,866 | Please write an abstract with title: Efficient VVC Intra Prediction Based on Deep Feature Fusion and Probability Estimation, and key words: Encoding, Feature extraction, Computational modeling, Complexity theory, Video coding, Kernel, Convolutional neural networks. Abstract: The ever-growing multimedia traffic has underscored the importance of effective multimedia codecs. Among them, the up-to-date lossy video coding standard, Versatile Video Coding (VVC), has been attracting attentions of video coding community. However, the gain of VVC is achieved at the cost of significant encoding complexity, which brings the need to realize fast encoder with comparable Rate Distortion (RD) performance. In this paper, we propose to optimize the VVC complexity at intra-frame prediction, with a two-stage framework of deep feature fusion and probability estimation. At the first stage, we employ the deep convolutional network to extract the spatial-temporal neighboring coding features. Then we fuse all reference features obtained by different convolutional kernels to determine an optimal intra coding depth. At the second stage, we employ a probability-based model and the spatial-temporal coherence to select the candidate partition modes within the optimal coding depth. Finally, these selected depths and partitions are executed whilst unnecessary computations are excluded. Experimental results on standard database demonstrate the superiority of proposed method, especially for High Definition (HD) and Ultra-HD (UHD) video sequences. |
6,867 | Please write an abstract with title: DiDDeM: a system for early detection of TCP SYN flood attacks, and key words: Floods, Computer crime, Traffic control, Monitoring, Telecommunication traffic, Routing, Command and control systems, Intrusion detection, Counting circuits, Distributed computing. Abstract: This paper presents the distributed denial-of-service detection mechanism (DiDDeM) system for early detection of denial-of-service attacks. The design requirements of the system are posited to demonstrate the requirements for an early detection system. An overview of the system is presented to show how these requirements are met. DiDDeM provides a two-tier detection approach. First, pre-filters (PFs) filter traffic for possible attacks. This is achieved through the application of both stateful and stateless signatures utilising routing congestion algorithms. Second, command and control (C/sup 2/) servers provide intra- and inter-domain co-operation and response to contain an attack within the routing infrastructure. The results for stateful and stateless signature detection of TCP SYN flood attacks are presented. |
6,868 | Please write an abstract with title: Robust Control in the Worst Case Using Continuous Time Reinforcement Learning, and key words: Robust control, Uncertainty, Design methodology, Conferences, Reinforcement learning, Approximation algorithms, Cybernetics. Abstract: Reinforcement learning (RL) is an effective method to design robust control. Uncertainty in the worst case requires large state-action learning space. The continuous time RL can solve this computational problem. In this paper, we modify the classical continuous time RL. Compared with the actor-critic (AC) algorithm, our method is more simple and more robust under the worst-case uncertainty. |
6,869 | Please write an abstract with title: On the instability of slotted aloha with capture, and key words: Power system modeling, Signal to noise ratio, Throughput, Fading, Channel state information, Collaborative work, Government, Stability analysis, Performance gain, Power control. Abstract: We analyze the stability properties of slotted Aloha with capture for random access over fading channels with infinitely-many users. We assume that each user node knows only its own uplink channel gain, and uses this decentralized channel state information (CSI) to perform power control and/or probability control. The maximum stable throughput (MST) for a general capture model is obtained by means of drift analysis on the backlog Markov chain. We then specialize our general result to a signal-to-interference-plus-noise ratio (SINR) capture model. Our analysis shows that if the channels of all users are identical and independently distributed (i.i.d.) with finite means, the system is unstable under any kind of power and probability control mechanism that is based only on decentralized CSI. |
6,870 | Please write an abstract with title: A Revised Version of the ATLAS Tile Calorimeter Link Daughterboard for the HL-LHC, and key words: Field programmable gate arrays, Particle beams, Clocks, Single event upsets, Large Hadron Collider, Performance evaluation, Monitoring. Abstract: The ATLAS Tile Calorimeter (TileCal) readout link and control daughterboard (DB) is the central on-detector hub of the new TileCal electronics upgrade for the high-luminosity large hadron collider (HL-LHC). The DB, which has undergone gradual redesigns during development, provides the connection between the on- and off-detector electronics via bidirectional fiber-optic links. Two CERN-developed, radiation hard GBTx application specified integrated circuits (ASICs) receive LHC timing signals and configuration commands through 4.8-Gb/s downlinks, which are in turn propagated to the front end through Xilinx Kintex Ultrascale field-programmable gate arrays (FPGAs). The Kintex FPGAs also continuously perform real-time readout and transmission of digitized photomultiplier (PMT) samples, detector control system (DCS) signals, and monitoring data through redundant pairs of 9.6-Gb/s uplinks. The DB design aims at minimizing single points of failure and improving the performance and reliability of the board. Apart from the GBTx devices, the DB design relies on radiation-qualified commercial off-the-shelf (COTS) components. Mitigation of radiation-induced single-event upsets (SEUs) in the FPGAs is performed by a combination of the Xilinx soft error mitigation (SEM) controller and triple-mode redundancy (TMR) schemes in the FPGA firmware. Data integrity is protected through forward error correction (FEC) in the downlinks and cyclic redundancy check (CRC) error verification in the redundant uplinks. This article presents the latest revision of the DB (version 6), a redesign that addresses single-event latch-up (SEL) behavior observed in the Kintex Ultrascale+ FPGAs used in the previous revision, and features a more robust power circuitry combined with an improved current monitoring scheme, enhanced performance of the analog-to-digital converter (ADC) read-out, and improved timing performance. |
6,871 | Please write an abstract with title: Design Trade-Off Analysis of Dry-Type Medium Frequency Transformers with Parallel Foil Windings, and key words: Power system measurements, Density measurement, Windings, Aluminum, Wires, Transformers, Conductors. Abstract: This paper addresses a design trade-off analysis of foil-wound medium frequency transformers for solid-state transformer applications. A design methodology is proposed in the study. A comparative study is performed on the effect of the choice of conducting material and the number of parallel winding layers on the design objectives. The analysis in this paper uses a combination of numerical and analytical loss estimation methods for various multi-physical loss components of MFTs. The advantages and limitations of using foil conductors in the MFT windings are carried out. |
6,872 | Please write an abstract with title: Short and Ultra-Short Baseline Navigation of the AUV for Bringing It to the Bottom Docking Device, and key words: Autonomous underwater vehicles, Navigation, Acoustics, Task analysis, Testing. Abstract: The article is dedicated to the issue of determining the coordinates and orientation angles of an autonomous underwater vehicle relative to a short-range high-frequency hydroacoustic system. The task of navigation involves the apparatus maneuvering which leads to the formation of zones with different acoustic visibility of emitters by the receiving elements of the apparatus, and the need for a consistent solution of the navigation problem with a decrease in the information received and the use of the results obtained at the initial stages of docking. |
6,873 | Please write an abstract with title: Analysis and design of macroblock pipelining for H.264/AVC VLSI architecture, and key words: Pipeline processing, Automatic voltage control, Very large scale integration, Encoding, Bandwidth, Hardware, Processor scheduling, Video sharing, Parallel processing, Computational complexity. Abstract: This paper presents a new macroblock (MB) pipelining scheme for H.264/AVC encoder. Conventional video encoders adopt two-stage MB pipelines, which are not suitable for H.264/AVC due to the long encoding path, sequential procedure, and large bandwidth requirement. According to our analysis of encoding process, an H.264/AVC accelerator is divided into five major functional blocks with four-stage MB pipelines to highly increase the processing capability and hardware utilization. By adopting shared memories between adjacent pipelines with sophisticated task scheduling, 55% of the bus bandwidth can be further reduced. Besides, hardware-oriented algorithms are proposed without loss of video quality to remove data dependencies that prevent parallel processing and MB pipelining. The H.264/AVC Baseline Profile Level Three encoder, which requires computational complexity of 1.8 tera-instructions per second (TIPS), is successfully mapped into hardware with our MB pipeline scheme at 100 MHz. |
6,874 | Please write an abstract with title: Bleaching relaxation in phosphate and silicate glasses doped with PbS quantum dots, and key words: Bleaching, Glass, Quantum dots, US Department of Transportation, Capacitive sensors, Indium, Quantum dot lasers, Absorption, Annealing, Wavelength measurement. Abstract: Summary form only given. Glasses doped with semiconductor quantum dots are being extensively studied as promising materials for various photonics applications The absorption spectra of the PbS-doped glass samples are presented in this paper. The bleaching relaxation was measured using the pump-probe technique. |
6,875 | Please write an abstract with title: Novel adaptive control system for stable teleoperation via internet, and key words: Adaptive control, Internet, Delay effects, Telerobotics, Programmable control, Communication system control, Optimal control, System identification, Real time systems, Prediction methods. Abstract: Random delays can cause instability in realtime closed-loop Internet-based telerobotic systems. We propose a novel approach for modeling the end-to-end time delay dynamics of the Internet using system identification, and use it for controlling real-time Internet-based telerobotic operations. When a single model is used, it needs to adapt to the operating conditions before an appropriate control mechanism can be applied. Slow adaptation may result in large transient errors. As an alternative, we propose to use an adaptive multiple model framework, and determine the best model for the current operating conditions to activate the corresponding controller. We employ multivariable wave prediction method to achieve this objective |
6,876 | Please write an abstract with title: High temperature performance of a SiC MESFET based oscillator, and key words: Temperature, Silicon carbide, MESFETs, Oscillators, Radio frequency, Thin film inductors, Tuning, FETs, Circuits, Substrates. Abstract: A hybrid, UHF-Band differential oscillator based on 10 W SiC RF Power Metal Semiconductor Field Effect Transistor (MESFET) has been designed, fabricated and characterized through 475 °C. The circuit is fabricated on an alumina substrate with thin film spiral inductors, chip capacitors, chip resistors, and wire bonds for all crossovers and interconnects. The oscillator delivers 15.7 dBm at 515 MHz into a 50 Ω load at 125 °C with a DC to RF conversion efficiency of 2.8 %. After tuning the load impedance, the oscillator delivers 18.8 dBm at 610 MHz at 200 °C with a DC to RF conversion efficiency of 5.8 %. Finally, by tuning the load and bias conditions, the oscillator delivers 4.9 dBm at 453 MHz at 475 °C. |
6,877 | Please write an abstract with title: Mitigation of Power Fluctuations of a Grid-Tied Wind Energy System Using Battery Storage System, and key words: Batteries, Wind turbines, Inverters, Fluctuations, Mathematical model, Renewable energy sources, Voltage control. Abstract: Wind energy is a clean, renewable and reliable source of energy. The demand for renewable energy is increasing because of its positive impact on the environment and assistance to the economy of countries. However, the output of wind turbines is unpredictable and characterized by variations due to changing weather conditions. This paper presents a simple voltage-current (V-I) controller based power smoothening of the grid-tied wind energy conversion system (WECS) using the battery energy storage system (BESS). Considerable reduction in power fluctuation is achieved with a simple control technique. The dynamic modelling and simulation study is accomplished in MATLAB/Simulink. |
6,878 | Please write an abstract with title: Interaction between various terrain portrayals and guidance/tunnel symbology concepts for general aviation synthetic vision displays during a low en-route scenario, and key words: Liquid crystal displays, Testing, Aerospace control, NASA, Aerospace safety, Machine vision, Aerospace simulation, Glass, Phase frequency detector, Navigation. Abstract: In support of the NASA Aviation Safety Program's Synthetic Vision Systems (SVS) Project, a series of piloted simulations were conducted to explore and quantify the relationship between candidate terrain portrayal concepts and guidance/tunnel symbology concepts, specific to General Aviation (GA). The experiments were conducted in a fixed based flight simulator equipped with two separate 6-inch Liquid Crystal Display (LCD) Head Down Displays, one serving as a glass cockpit style Primary Flight Display (PFD) and the other as a Navigation Display (ND). This work is the second part of a three-part study related to the Symbology Development for Head Down Displays (SD-HDD) test series. The focus of this experiment was on advanced low altitude en route maneuvers simulating a transition into Instrument Metrological Conditions (IMC) in the central mountains of Alaska (Merrill Pass). A total of 18 GA pilots, with three levels of pilot experience, evaluated a test matrix of four terrain portrayal concepts (TPC) and six guidance/tunnel symbology (GSC) concepts. Both quantitative and qualitative measures were recorded and analyzed. Quantitative measures included all pilot/aircraft performance data, flight technical errors (FTE), flight control inputs, and selected physiological data. The qualitative measures included pilot comments and pilot responses to the structured questionnaires such as perceived workload, subjective Situation Awareness (SA), pilot preferences, and the rare event recognition. Only a sample of the results of FTE, SA and workload is reported here. There were statistically significant effects found from GSC and TPC but no significant interactions between TPCs and GSCs for this experiment. Lower FTE and increased SA were achieved using SVS displays, as compared to the baseline Pitch/Roll Flight Director (PRFD) and Blue Sky Brown Ground (BSBG) combination. These results indicate that all pilots performed very well, mostly within the 75ft of vertical and lateral limits indicated by one dot of the course deviation indicators. With the same SVS training provided to all three groups, low time VFR pilots performed as well as IFR pilots in low altitude en-route scenario with IMC. Overall those GSCs that have both Guidance Cue and Tunnel performed better than the other concepts. |
6,879 | Please write an abstract with title: Model for Some Nonthermal Effects of Radio and Microwave Fields on Biological Membranes, and key words: Biological system modeling, Biomembranes, Radio frequency, Voltage, Biological materials, Lead, Equations, Permeability, Blood, Cells (biology). Abstract: A model is presented for mechanisms by which non-thermal effects could take place in biological materials as a result of microwave, radio-frequency fields. Both shifts in ion concentrations across a membrane and the orientation of long chain molecules are shown to be possible. |
6,880 | Please write an abstract with title: Application of principal component analysis to the FTIR spectra of disk lubricant to study lube-carbon interactions, and key words: Principal component analysis, Lubricants, Bonding, Area measurement, Thickness measurement, Spine, Eigenvalues and eigenfunctions, Chemical analysis, Spectral analysis, Tribology. Abstract: Lubricant molecules on carbon surfaces are typically present in two distinctive chemical-physical environments, conventionally referred to as bonded and free lubricant. We observe and analyze the spectral shift in the lubricant FTIR spectrum using principal component analysis (PCA) to quantify and understand the bonded and free lubricant states for the lubricant systems Zdol, AM, and ZTetraol. In addition, we performed extended PCA to elucidate lubricant interactions with phosphazene additives. PCA of FTIR spectra is found to be a viable method in quantifying bonded lube ratio as well as in studying the mechanism of lubricant and phosphazene additive-carbon interactions. |
6,881 | Please write an abstract with title: Intelligent decision support and information systems in enterprise: evolutionary-based optimization, and key words: Information systems, Application software, Decision support systems, User interfaces, Databases, Software systems, Search engines, Computer interfaces, Knowledge management, Logic. Abstract: Most of the existing search systems ''software' are modeled using crisp logic and queries. We introduce fuzzy querying and ranking as a flexible tool allowing approximation where the selected objects do not need to match exactly the decision criteria resembling natural human behavior. The model consists of five major modules: the fuzzy search engine, the application templates, the user interface, the database and the evolutionary computing. The system is designed in a generic form to accommodate more diverse applications and to be delivered as stand-alone software to academia and businesses. |
6,882 | Please write an abstract with title: Outage of Cognitive Electric Vehicle Networks Over Mixed RF/VLC Channels With Signal-Dependent Noise and Imperfect CSI, and key words: Radio frequency, IP networks, Jamming, Relays, Signal to noise ratio, Interference, Channel estimation. Abstract: In this paper, we propose a novel jamming-robust communication technique for the outdoor cognitive EV-enabled network over mixed radio-frequency (RF)/visible light communication (VLC) channels with signal-dependent noise. One EV acts as a relaying node to allow an aggregator to reach the jammed EV and, at the same time, operates in both RF and VLC spectrum bands while satisfying interference constraints imposed by the primary network entities. We derive an exact closed-form analytical expression for the outage probability and also provide its asymptotic analysis while considering various channel state information quality scenarios. Finally, simulation results validate the accuracy of our analysis. |
6,883 | Please write an abstract with title: High-Density Directional Display for Generating Natural Three-Dimensional Images, and key words: Three dimensional displays, Image generation, Fatigue, Liquid crystal displays, Eyes, Convergence, Prototypes, Humans, Optical arrays, Optical imaging. Abstract: A high-density directional display can produce natural three-dimensional(3-D) images by projecting a large number of directional images using directional rays. When the angle pitch of the directional rays is 0.2/spl deg//spl sim/0.4/spl deg/, more than two directional rays passing through a point in 3-D space enter the viewer's eye simultaneously so that the viewer's eye can focus on that point. No discrepancy appears between the convergence function and the accommodation function so that the display does not induce visual fatigue. Two different system configurations are presented: a projection configuration and a thin configuration. A prototype display based on the projection configuration was constructed. The prototype display displayed 64 directional images with directional rays having a horizontal angle pitch of 0.34/spl deg/. The screen size was 9.2 in. The preliminary experimental results showed that a viewer could focus on 3-D images produced by the prototype display. |
6,884 | Please write an abstract with title: Lateral field emitter with thin-film Au emissive layer, and key words: Transistors, Gold, Etching, Fabrication, Chromium, Silicon compounds, Threshold voltage, Plasma measurements, Photonics, Ultrafast electronics. Abstract: Lateral field emitters have been investigated for years as an alternative source of free electrons. Lateral construction seems to be easier from fabrication point of view, but the micrometer size cathode-anode/gate distance depends mainly on nano-lithographic procedures. In this work we have shown silicon/silicon dioxide/gold lateral emitters, made by controlled under etching of sandwich layer, possessing surprising good emissive properties. Turn-on voltage was of about 6 V in vacuum and 8 V in an air, the threshold field of 0.25 V//spl mu/m and the maximal emission current of about 5 /spl mu/A for 15 V. |
6,885 | Please write an abstract with title: Analysis of All-to-all Collective Operations on Hierarchical Computer Clusters, and key words: Prediction algorithms, Communication networks, Communication channels, Software, Resource management, Program processors, Software algorithms. Abstract: In this paper, we consider implementation algorithms of broadcast-cyclic exchanges, also called All-to-all. The choice of the total exchange patterns is due to its widespread using collective communication in supercomputer simulation packages. Authors have developed a software for predicting the execution time of the All-to-all operation on the given subsystem of nodes. A software uses the results of an experimental estimate of the performance degradation for the MPI_Send/MPI_Recv operations during simultaneous use of the communication channel by a set of processes. We analyze the dependence of the All-to-all patterns passing time on the size messages when MPI- processes share the communication channels. Authors have developed recommendations about All-to-all operation implementation algorithms. |
6,886 | Please write an abstract with title: An Efficient Revocable and Searchable MA-ABE Scheme With Blockchain Assistance for C-IoT, and key words: Internet of Things, Encryption, Servers, Cloud computing, Blockchains, Security, Task analysis. Abstract: Internet of Things (IoT) devices usually stores data on clouds for computational overhead offloading and easy data sharing. The data owners, as a result, usually have concerns about the security and privacy of their data stored in such cloud-assisted IoT (C-IoT) systems. Traditional encryption and search primitives, including attribute-based encryption (ABE) and public-key encryption with keyword search (PEKS), however, suffer from high overheads in decryption and revocation, and privacy leakage in search. To address these issues, we propose an efficient revocable and searchable multiauthority ABE (MA-ABE) scheme named ERS-ABE, which utilizes blockchain (BC) technology to implement keyword-based search and dynamic user management. ERS-ABE also adopts cloud-assisted decryption to improve the efficiency of IoT devices. It has been proven to be secure against the selective replayable chosen-ciphertext attacks and the chosen-keyword attacks under the random oracle model. The feasibility and efficiency of ERS-ABE have been evaluated through theoretical analysis and extensive simulation studies. The results indicate that EAR-ABE performs better over the state-of-the-art in both storage and computational overheads. Particularly, the operations that are usually done by a central server but taken by a BC in EAR-ABE cost only a few seconds. |
6,887 | Please write an abstract with title: Broadband Diffractive Neural Networks, and key words: Optical filters, Broadband communication, Neural networks, Optical fiber networks, Frequency measurement, Task analysis, Optical diffraction. Abstract: Broadband diffractive neural networks that process a continuum of wavelengths for task-specific component design and all-optical inference are presented. This framework is experimentally demonstrated by designing spectral filters and a spatially-controlled demultiplexer at THz wavelengths. |
6,888 | Please write an abstract with title: TRA: an efficient dynamic resource assignment algorithm for MCF-based SS-FONs, and key words: Heuristic algorithms, Modulation, Repeaters, Routing, Optical fiber networks, Optical sensors, Optical crosstalk. Abstract: Service provisioning can be enhanced with spectrally spatially flexible optical networks (SS-FONs) with multicore fibers; however, intercore crosstalk (XT) is a dominant impairment that complicates the problem of maintaining the quality of transmission (QoT) and resource allocation. The selection of modulation formats (MFs), due to their unique XT sensitivities, further increases the complexity. The routing, modulation, core, and spectrum assignment (RMCSA) problem must select the resources carefully to exploit the available capacity while meeting the desired QoT. In this paper, we propose an RMCSA algorithm called the tridental resource assignment (TRA) algorithm for transparent SS-FONs, and its variant, translucency-aware TRA (TaTRA), for translucent SS-FONs. TRA balances three different factors that affect network performance under dynamic resource allocation. We consider translucent networks with flexible regeneration and with and without modulation and spectrum conversion. Our resource assignment approach includes both an offline network planning component to calculate path priorities and an online/dynamic provisioning component to allocate resources. Extensive simulation experiments performed in realistic network scenarios indicate that TRA and TaTRA significantly reduce the bandwidth blocking probability by several orders of magnitude in some cases. |
6,889 | Please write an abstract with title: Subspace-based estimation method of uplink FIR channel in MC-CDMA system without cyclic prefix over frequency-selective fading channel, and key words: Finite impulse response filter, Multicarrier code division multiple access, Multiaccess communication, Intersymbol interference, Baseband, Channel estimation, Multiple access interference, Wireless communication, Frequency estimation, Frequency-selective fading channels. Abstract: The multipath nature of the wireless channel can be described as a finite impulse response (FIR) filter, which easily results in hostile intersymbol interference (ISI). Usually, multicarrier code-division multiple access (MC-CDMA) systems combat the hostile ISI with the aid of the cyclic prefix (CP). Nevertheless, the elimination of ISI in MC-CDMA systems is at the cost of reduction in spectral efficiency. To recover spectral efficiency, it is meaningful to investigate MC-CDMA systems without CP. This paper explores the estimation of the uplink FIR channel in the MC-CDMA system without CP. We interpret the MC-CDMA system without CP as an equivalent time-domain ISI-corrupted direct sequence (DS-) CDMA system. Based on subspace techniques, an uplink FIR channel estimation scheme is derived for the MC-CDMA system without CP. Simulations demonstrate the validity and the performance of the proposed uplink FIR channel estimation scheme. |
6,890 | Please write an abstract with title: A Multimodal Machine Learning Approach to Diagnosis, Prognosis, and Treatment Prediction for Neurodegenerative Diseases and Cancer, and key words: Webcams, Computational modeling, Neural networks, Medical services, Predictive models, Feature extraction, Data models. Abstract: Despite early diagnosis and estimating the future course of neurodegenerative and cancerous diseases being integral for survival of patients, clinical and algorithmic methods fail to effectively utilize the multimodal data available, are time-inefficient, and expensive, making it difficult to access accurate screenings for these diseases. Therefore, a novel end-to-end quantum machine learning approach using multiple data modalities for the identification of diagnoses, prognoses, and effective treatments is proposed. In a procedural flow, data is sourced from one or more of the following: CT scan images, webcam, patient-physician audio, Whole Slide Images, and clinical data. For image data, a Convolutional Neural Network, is employed to detect high level features. With text-based clinical data (including audio-derived data), a Bidirectional Encoder Representation model is used to extract text embeddings. For video data, pupil progression and average fixation duration features are manually crafted. All feature vectors are concatenated, normalized, passed through a Deep Neural Network, and then mapped to one of 38 neurodegenerative and cancerous diseases. For prognosis, features are pooled, concatenated with the diagnosis feature vector, and passed through another neural network with an output of survival times. Treatment prediction involves an information-retrieval task matching feature vectors to treatments/drug lists from the FDA. The proposed approach was tested on 5,000 patient profiles sourced from the public TCGA and JPND databases, outperforming all other state-of-the-art approaches. The model predicted diagnoses with an accuracy of 98.53%, achieved a Concordance Index of 0.94 in predicting prognoses, and in treatment prediction achieved a 99.32% accuracy. |
6,891 | Please write an abstract with title: A Study and Evaluation of Classifiers for Anti-Spam Systems, and key words: Unsolicited e-mail, Databases, Support vector machines, Training, Feature extraction, Proposals, Postal services. Abstract: The volume of e-mails has been increasing in recent years. However, since 2005, at least half of these e-mails have been made up of spam. This massive traffic of unwanted messages causes losses to users, such as the excessive and unnecessary use of the bandwidth of their networks, loss of productivity, exposure of inappropriate content to inappropriate audiences etc. This paper proposes the study and the application of machine learning models to the classification of e-mails in existing anti-spam systems and, in particular, in the new anti-spam system Open-MaLBAS. After carrying out many experiments on different data sets, it was possible both to prove the feasibility of the proposal and to develop a powerful combination of techniques, methods, and models that can be successfully applied to the classification of e-mails in anti-spam systems. |
6,892 | Please write an abstract with title: 0.18 /spl mu/m SBT-based embedded FeRAM operating at a low voltage of 1.1 V, and key words: Random access memory, Ferroelectric films, Nonvolatile memory, Low voltage, Hydrogen, Electrodes, Capacitors, Plugs, Degradation, Passivation. Abstract: We have successfully developed a 0.18 /spl mu/m SBT-based 1 Mbit embedded FeRAM, which operates at a very low voltage of 1.1 V and ensures the data retention time up to 1000 hours at 125/spl deg/C. The low voltage operation and high reliability characteristics of 0.18 /spl mu/m embedded FeRAM are the first demonstration to our knowledge. These excellent characteristics have been attained by newly developed FeRAM completely encapsulated by hydrogen barriers. |
6,893 | Please write an abstract with title: Measurement of the noise in a linear two-port device, and key words: Noise measurement, Reflectivity, Stokes parameters, Noise level, Covariance matrix, Temperature dependence, Equations, Impedance, Gaussian noise. Abstract: It is well known that the noise factor of a linear two-port depends on the impedance (or reflectance) of the source connected to it. This is easily understood if the noise sources inside the device are replaced by equivalent amplitude sources, one at each port. These sources produce outward traveling waves which are, in general, partially correlated. Thus if the wave at port 1 is reflected by the source mismatch it will interfere with the wave at 2 in a manner that depends on the source reflectance W. |
6,894 | Please write an abstract with title: A simple measurement for harmonic source localization, and key words: Power system harmonics, Harmonic distortion, Voltage, Distortion measurement, Power system planning, Pollution measurement, Frequency, Performance evaluation, Power measurement, Power distribution. Abstract: A simple measurement is proposed for source identification and characterization. Power transformer is proposed as a point to perform the measurements in a cheap and practical way. Simulation has been undertaken to confirm validity of the proposed method. The procedure for the load characterization, outlined in this paper, has been tested in real power distribution system to establish the contribution of the certain industrial customer to the harmonic distortion. In contrary to previous assumption, it has been found out that the analyzed customer is not dominant source of distortion and is only partially responsible for the harmonic distortion at the PCC. |
6,895 | Please write an abstract with title: Investigating How Software Characteristics Impact the Effectiveness of Automated Software Fault Tolerance, and key words: Benchmark testing, Software, Single event upsets, Fault tolerance, Synchronization. Abstract: A number of publications have examined automated fault tolerance techniques for software running on commercial off-the-shelf microcontrollers. Recently, we published an automated compiler-based protection tool called COmpiler Assisted Software fault Tolerance (COAST), a tool that automatically inserts dual- or triple-modular redundancy into software programs. In this study, we use COAST to explore how the effectiveness of automated fault protection varies between different benchmarks, tested on an ARM Cortex-A9 platform. Our hypothesis is that certain benchmark characteristics are more likely than others to influence the effectiveness of automated fault protection. Through neutron radiation testing at the Los Alamos Neutron Science Center (LANSCE), we show that cross section improvements vary from 1.6× to 54× across eight benchmark variants. We then explore the characteristics of these benchmarks and investigate how properties of these benchmarks may impact the effectiveness of automated fault protection. Finally, we leverage a novel fault injection platform to isolate two of these benchmark characteristics and validate our hypotheses. |
6,896 | Please write an abstract with title: Variable-rate turbo bit-interleaved coded modulation, and key words: Interleaved codes, Modulation coding, Turbo codes, AWGN channels, Additive white noise, Gaussian noise, Iterative decoding, Transmitters, Quadrature amplitude modulation, Error probability. Abstract: This paper studies the performance of variable-rate turbo bit-interleaved coded modulation (Turbo-BICM) with random puncturing. A union-Bhattacharyya rate threshold for the variable-rate Turbo-BICM is derived. A closed form approximation of this rate threshold is determined for an AWGN channel and shown to predict the Turbo-BICM iterative decoding performance very well. |
6,897 | Please write an abstract with title: Employee Promotion Prediction by using Machine Learning Algorithms for Imbalanced Dataset, and key words: Support vector machines, Radio frequency, Training, Machine learning algorithms, Key performance indicator, Organizations, Artificial neural networks. Abstract: Promotion processes are one of the most important processes in terms of human resources. A promotion process organized fairly within the organization is a managerial tool that motivates employees and contributes to business continuity. Promotion is an important extrinsic motivation for many employees. It ensures the employee’s engagement and commitment to the organization and contributes to the continuity of his current performance. It is also an important rewarding and performance control mechanism for the organization. Many factors such as seniority, performance level, competencies, age, awards, training score, organizational commitment of the personnel who will be promoted are taken into consideration. In this study, a prediction methodology will be studied based on the criteria evaluated for the employees in the promotion processes by Machine Learning algorithms such as Support Vector Machine, Artificial Neural Network, and Random Forest. Random Forest achieved the highest performance with 98% accuracy, 96% precision, 1.0% recall and 98% f1-score values with ROS approach. This study could be used by HR and manager to predict the probability of promotion so that managers can find the right parameters for someone to get promoted. |
6,898 | Please write an abstract with title: Modeling, identification, and control of large-scale dynamical systems, and key words: Large-scale systems, Radar tracking, Optimal scheduling, Active noise reduction, Noise measurement, Time measurement, State-space methods, Passive radar, Sensor systems, Equations. Abstract: This paper highlights some fundamental issues involved in the study of large-scale dynamical systems. Two particular topics are discussed in some detail, one dealing with the management of active sensors via partially observable Markov decision processes, and the other dealing with the modeling, recognition and tracking of multi-function radars in an electronic warfare environment. |
6,899 | Please write an abstract with title: Modification of the IRI Electron Density Profile from an Observation Ionogram Using the Full Wave Method in the Lower Ionosphere, and key words: Rough surfaces, Ionosphere, Springs, Electromagnetics, Delays, Time-frequency analysis, Photonics. Abstract: As the International Reference Ionosphere (IRI) is very useful, the difference between the IRI profile and the actual profile must be checked constantly. For the electron density profile, ionograms are effective data to know the actual lower ionospheric conditions. Now, only special data such as foE and foF2 are used in the ionogram information, though the ionograms have much information of both apparent heights and reflection coefficients on observation frequencies. We suggest a method that estimate the delay time from both the electron density profile and the collision frequency profile by the full wave calculation. In this paper, we investigate difference between the measured ionogram and the IRI theoretical ionogram for one example. And we modify the IRI electron density profile so that the calculated ionogram fit to the measured ionogram. |
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