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14,800 | Please write an abstract with title: Pixel-wise human motion segmentation using learning vector quantization, and key words: Humans, Motion segmentation, Computer vision, Vector quantization, Image segmentation, Video sequences, Data mining, Shape, MPEG 4 Standard, Multimedia communication. Abstract: This paper proposed an efficient human motion segmentation algorithm with pixel-wise accuracy. Our aim is to solve the problem of separating human image as object of interest from the background image. In our approach, every pixel of a video sequence frame is considered to be a 5-dimensional vector, consisting of pixel position coordinate components (x,y coordinates) plus pixel color information in HSV (Hue, Saturation, and Value). First, the human assistant is employed to create the reference frame of desired human object of interest. This step is done only at the first frame of video sequence. The Kohonen Learning Vector Quantization (LVQ) is then used to give optimal class region decision between the human object class and background class by training its codebook vectors, supervised by reference frame. The segmentation result is generated by doing vector quantization of LVQ codebook vectors to all pixels of image frame. Finally, for adapting the human object class movement in succeeding frames, LVQ codebook vectors are updated periodically by feeding back the result of the last segmentation into the training step. This paper also presents proposed segmentation algorithm performance to some MPEG-4 video test. |
14,801 | Please write an abstract with title: A Cooperative Optimization Strategy for Access and Reconfiguration of Microgrids, and key words: Electrical engineering, Renewable energy sources, Simulation, Distribution networks, Microgrids, Electric vehicles, Particle swarm optimization. Abstract: The random access of the microgrids (MGs) to distribution network and disordered operation will result in high network loss. Aiming at this problem, a double-loop cooperative optimization strategy for optimizing network loss is proposed. This strategy builds an optimization model based on MGs with electric vehicles (EVs) and renewable energy sources (RES). The inner-loop model reconfigures the network structure of MGs through optimization to reduce the basic network loss of the MGs. The outer-loop model optimizes the node location of the MG accessed to the distribution network in the MGs to reduce the increased network loss. The inner-loop and outer-loop synergistically reduce the total network loss of the MGs. Particle swarm optimization (PSO) is used to solve the model. Finally, four simulation cases are used to prove the rationality and feasibility of the proposed strategy. |
14,802 | Please write an abstract with title: Joint Satellite Gateway Placement and Routing for Integrated Satellite-Terrestrial Networks, and key words: Logic gates, Satellites, Routing, Load modeling, Delays, Linear programming, Propagation delay. Abstract: With the increasing attention to the integrated satellite-terrestrial networks (ISTNs), the satellite gateway placement problem becomes of paramount importance. The resulting network performance may vary depending on the different design strategies. In this paper a joint satellite gateway placement and routing strategy for the terrestrial network is proposed to minimize the overall cost of gateway deployment and traffic routing, while adhering to the average delay requirement for traffic demands. Although traffic routing and gateway placement can be solved independently, the dependence between the routing decisions for different demands makes it more realistic to solve an aggregated model instead. We develop a mixed integer linear program (MILP) formulation for the problem. We relax the integrality constraints to achieve a linear program (LP) which reduces time-complexity at the expense of a sub-optimal solution. We further propose a variant of the proposed model to balance the load between the selected gateways. |
14,803 | Please write an abstract with title: Wildfire Detection Using Streaming Satellite Imagery, and key words: Training, Satellites, Instruments, Fires, Geoscience and remote sensing, Streaming media, Computational efficiency. Abstract: We propose a novel wildfire detection algorithm for multispectral satellite images. By observing that wildfire pixels are sparse outliers residing in a spatially correlated background, we isolate them using robust principal component analysis. A novel cloud masking approach based on T-point thresholding is also proposed to reduce false alarms. Compared to existing methods, our proposed method adapts to the spatial and temporal heterogeneity of satellite images, does not require training on labeled images, and is computationally efficient for online monitoring. We present an application of our proposed algorithm to the GOES-R imagery in monitoring recent California wildfires. |
14,804 | Please write an abstract with title: Generic architecture for a management system of automatic switched transport networks, and key words: Optical fiber networks, Automatic control, Telecommunication switching, Control systems, Telecommunication control, Routing, Network interfaces, Testing, Environmental management, Optical control. Abstract: An ASTN (automatic switched transport network) enhances the traditional transport network by a control plane. The control plane implements signalling and routing mechanisms that allow the automatic configuration of end-to-end connections on client requests. Consequently the management of ASTNs requires integrated management of the control plane layer and the underlying transport network. This article describes a generic architecture for ASTN management systems tuned to this requirement. The centre piece of this architecture is a generic CORBA network level interface which allows an easy integration of several layer networks and different administrative domains. In order to evaluate this architecture it will be implemented for an IP over ASON (automatic switched optical network) field trial developed within the IST (Information Societies Technology) project LION (Layers Interworking in Optical Networks). The LION management system is designed for a multi-vendor, multi-technology, and multidomain environment. This contribution gives a description of the architectural concepts used, the existing frameworks adopted, the design of the network level interface, and experiences made during implementation of the concepts for the LION field trial. |
14,805 | Please write an abstract with title: Analysis of Utilization of UGTV as A Distance Learning Media during the Covid 19 Pandemic, and key words: Computer aided instruction, Production management, Pandemics, Social networking (online), Education, Globalization, Broadcasting. Abstract: The rapid development of Information Communication Technology-ICT in the current era of globalization cannot be avoided its influence on the world of education anymore. Global demands require the world of education to consistently and constantly adapt technological developments to improve the quality of education. Universitas Gunadarma has an educational broadcasting medium, Universitas Gunadarma Television (UGTV), used as a distance learning medium. This study aimed to analyze the use of digital UGTV as a student distance learning media during the pandemic. The method used is UGTV live broadcasting collaboration with zoom cloud meeting. The application of blended learning methods, both synchronously and asynchronously, continues to be carried out. The results of this study, UGTV developed many literacy programs, team teaching, UGTalk, and all learning shows can be watched again on the official UGTV YouTube. |
14,806 | Please write an abstract with title: Applications of metrology for optical coherence tomography, and key words: Metrology, Tomography, Biomedical optical imaging, Optical refraction, Optical variables control, Optical scattering, Biomedical engineering, Refractive index, Biomedical imaging, Instruments. Abstract: Optical coherence tomography (OCT) is a novel technique that has recently emerged as a promising biomedical imaging modality in ophthalmology, cardiology, oncology and a number of other medical disciplines. Basic contrast mechanism for OCT is gradient in refractive index of tissue constituents. Additional contrast mechanisms include Doppler, polarization and phase-sensitive imaging modalities. Applications of metrology include high-resolution spectrum analyzers for spectral domain OCT instrumentation development and characterization of refractive index of tissue constituents. |
14,807 | Please write an abstract with title: Design and control of axial-flux brushless DC wheel motors for electric Vehicles-part II: optimal current waveforms and performance test, and key words: Optimal control, Wheels, DC motors, Brushless DC motors, Brushless motors, Electric vehicles, Testing, Gears, Constraint optimization, Torque. Abstract: We present dedicated designs of optimal current waveforms for disk-type axial-flux wheel motors. The four-phase dedicated wheel motor has been designed and installed directly inside the wheel of electrical vehicles without mechanical differentials and reduction gears. We performed a torque-oriented optimization to obtain the optimal current waveform subject to various constraints for the independent winding structure. We found that the best optimal waveform with maximized torque and confined ohmic loss is proportional to the magnetic flux variation in the air gap between the stator and the rotor and has the same shape as the back-electromotive force (EMF). This finding is confirmed by both theoretical and numerical analyses. As expected, the current control waveform of the back-EMF extracted by experiments renders the best performance in terms of maximum torque and motor efficiency. |
14,808 | Please write an abstract with title: Measurement and modeling of the transfer function of a monolithic SOA-EA 2R-regenerator, and key words: Transfer functions, Semiconductor optical amplifiers, Repeaters, Optical losses, Nonlinear optics, Absorption, Power measurement, Optical interferometry, Optical saturation, Concatenated codes. Abstract: We have measured steep power transfer characteristics with tunable threshold for a monolithic 2R-regenerator combining amplifying and absorbing sections. Modeling results explain the basic characteristics. |
14,809 | Please write an abstract with title: Monocular Human Shape and Pose with Dense Mesh-borne Local Image Features, and key words: Training, Three-dimensional displays, Shape, Convolution, Pose estimation, Pipelines, Transforms. Abstract: We propose to improve on graph convolution based approaches for human shape and pose estimation from monocular input, using pixel-aligned local image features. Given a single input color image, existing graph convolutional network (GCN) based techniques for human shape and pose estimation (e.g. [19]) use a single convolutional neural network (CNN) generated global image feature appended to all mesh vertices equally to initialize the GCN stage, which transforms a template T-posed mesh into the target pose. In contrast, we propose for the first time the idea of using local image features per vertex. These features are sampled from the CNN image feature maps by utilizing pixel-to-mesh correspondences generated with DensePose [11]. Our quantitative and qualitative results on standard benchmarks show that using local features improves on global ones and leads to competitive performances with respect to the state-of-the-art. |
14,810 | Please write an abstract with title: Computer-assisted detection of ischemia utilizing echocardiograms before and after stress, and key words: Ischemic pain, Stress, Image segmentation, Myocardium, Motion estimation, Echocardiography, Arteries, Image analysis, Active contours, Monitoring. Abstract: Myocardial ischemia induced by stress may produce abnormalities of left ventricular (LV) wall motion. The location of wall motion abnormalities may be used to estimate the location and severity of coronary arterial obstructions. The American Society of Echocardiography has recommended the use of a 16-segment model of LV for assessment of wall motion abnormalities. Evaluation of motion of each segment of LV can be used to localize wall motion abnormalities (anterior, inferior, and lateral). Wall motion abnormalities can then be assigned to the distribution of each coronary artery. The normal response of the LV to stress is a uniform increase of regional wall motion, thickening and a reduction in end-systolic LV cavity volume, with minimal changes in diastolic cavity volume. Thus, echocardiographic comparison of LV performance before and after stress can be used to detect reversible myocardial ischemia. Computer-assisted detection of ischemia is based on a quantitative analysis of LV wall thickness at end-diastole and end-systole. This paper presents an approach to computer-assisted detection of ischemia utilizing proper boundary identification, segmentation and comparative analysis of wall segments. The proper boundary identification includes an image pre-processing stage, contour detection and segmental analysis. The algorithm used in this study combines the detection of endocardial and epicardial boundaries, and the computation of the area of segments of LV wall. The technique is a modified form of two-phase relaxation active contour detection. The analysis of the LV wall segments before and after stress includes the computation of the area of a segment at end-diastole and end-systole. These areas provide the key values for monitoring LV wall motion. |
14,811 | Please write an abstract with title: TACTimat: Exploring the Design Factors of An Effective Touch Based Tool for Stimulation Therapy, and key words: Art, Shape, Conferences, Medical treatment, Tools, Haptic interfaces. Abstract: TACTimat is a therapy tool developed for both hyper and hyposensitive children through a novel art and design focused approach. Our initial study explores how shape, texture, and density of elements on a tactile mat may influence the behaviour of young children with an Autistic Spectrum Disorder (ASD) or other cognitive disability during tactile exploration. |
14,812 | Please write an abstract with title: Two semi-active approaches for vibration isolation: piezoelectric friction damper and magnetorheological damper, and key words: Shock absorbers, Damping, Friction, Control systems, Vibration control, Piezoelectric actuators, Isolators, Bandwidth, Hydraulic actuators, Voltage. Abstract: Two different approaches to perform vibration isolation control on a single-degree-of-freedom system using semiactive dampers are investigated. In the first approach, the friction damper consists of an actuator, which is based on a piezoelectric stack with a mechanical amplifying mechanism that provides symmetric forces within the isolator. The advantages of such an actuator are its high bandwidth, displacement response and its ability to operate in vacuum environments such as in space. The damper is constrained to move using an air bearing that produces a virtually ideal single-degree-of-freedom spring-mass system. Within this work, the actuating ability of the friction-based actuator is characterized. The relationship between the force generated by the actuator and the applied voltage was found to be linear. In the second approach, a magnetorheological (MR) fluid damper is designed and fabricated. This damper is ideal for use in a semi-active control system where the damping characteristics can be adjusted by varying the amount of current applied to the damper. |
14,813 | Please write an abstract with title: Spatial multiplexing for large-area 3D holographic recording, and key words: Holography, Optical pulses, Optical fibers, Fiber lasers, Lighting, Optical films, Stability, Optical recording, Vibration measurement, Isolation technology. Abstract: In this paper, we have realized a simple and efficient method to simplify the pulsed holography and holographic interferometry recording process and render such field applications feasible using low-energy laser pulses from a compact transportable system. Our method is based on masked sequential recording of small parts of the object on corresponding adjacent holographic film areas by employing a single laser pulse for each recording step. We have generated spatially multiplexed hologram consisting of a mosaic of rectangular "frames", each "frame-hologram" reconstructing a part of the object. |
14,814 | Please write an abstract with title: System Level Performance Degradation Prediction for Power Converters Based on SSA Elman NN and Empirical Knowledge, and key words: power converter, system-level prediction, performance degradation, SSA-Elman Neural Network. Abstract: The degradation of power converter perfor-mance is one of the most critical issues of complex system with the improvement of power capacity and density. Power converter bears severe electrical and thermal stress, resulting in an increase in the probability of failure and significant economic losses. Most research addresses performance evaluation either through reliability theory without physical understanding or through data-driven methods requiring high experimental cost. Few studies focus on predicting system-level performance degradation, which is technically difficult as many components degrade randomly. Identifying the parameters of electronic com-ponents based on sensor data has become possible with the development of neural networks and computational power. Therefore, this paper proposes a novel system-level power degradation predicting framework, which combines the advantages of neural networks in nonlinear fitting and empirical knowledge to predict the degradation of power converter. In addition, a comprehensive and improved feature parameter screening method is proposed to iden-tify the most critical feature parameters of the power con-verter systems. Furthermore, the neural network parameter identification method based on SSA-Elman NN (Sparrow Search Algorithm - Elman Neural Network) is introduced to improve prediction accuracy. Finally, the result shows that the proposed method can accurately predict the degrada-tion of the system by using a DC-DC converter as an ex-ample. |
14,815 | Please write an abstract with title: Deep Learning for Marine Bioacoustics and Fish Classification Using Underwater Sounds, and key words: Deep learning, Biological system modeling, Computational modeling, Ecosystems, Noise reduction, Network architecture, Fish. Abstract: The migration of species is an important factor in the analysis of ecological systems. Changes in migratory patterns of a species or a specific group in an ecosystem often follow changes in the environment - many animals are sensitive to small changes that may not initially be thought of as significant for the health of an ecosystem. The presence of many species can be detected by the sounds they produce, and as such, environmental conservation efforts have much to gain from the automation of the analysis of Bioacoustics. Deep Learning shows promise for this type of task. This work evaluates the performance of different deep learning methods when performing the task of detecting the presence of brown meagre sounds in spectrograms with different window lengths and achieves an F1-score of 0.94 for brown meagre vocalization detection. |
14,816 | Please write an abstract with title: A ranging method based on triangulation for robotic control, and key words: Robot control, Layout, Robotics and automation, Robot vision systems, Cameras, Orbital robotics, Light sources, Automatic control, Laboratories, Shape. Abstract: A ranging method is presented that is being developed at the Robotics and Automation Laboratory at R.P.I. The method can be used to locate objects of different shape in 3-D space. A camera at a fixed position is observing a scene and a light source attached to a robot arm sending a beam of light to the scene represent the hardware used. The position of the camera and the light source along with the picture of the scene provide enough information to compute the reflection point of the light beam in the scene. An error analysis of the process, the robot arm and the camera system are presented and the results of the implementation discussed. |
14,817 | Please write an abstract with title: Tunable backscattering for single-mode optical fibers in 1.1-1.6-µm spectral region, and key words: Backscatter, Optical fibers, Optical fiber polarization, Optical fiber testing, Tunable circuits and devices, Stimulated emission, Laser excitation, Fiber lasers, Laser tuning, Pump lasers. Abstract: A very powerful and versatile backscattering apparatus for single-mode fibers has been implemented, which can be tuned to almost every wavelength in the spectral region from 1.06 to 1.6 μm. A Raman source fiber, pumped by a Nd:YAG laser, is filtered by a special conception monochromator (folded path) which, by preserving the image of the output face of the source fiber, allows good launching efficiency into the fiber under test. Directional coupling with suppression of Fresnel reflection is achieved by an acoustooptic modulator, which is insensitive to polarization. Applications to single-mode fibers characterization are discussed, like spectral attenuation, cutoff phenomena as function of length and spot-size propagation. |
14,818 | Please write an abstract with title: A Spatial Off-Resonance Correction in Spirals for Magnetic Resonance Fingerprinting, and key words: Spirals, Image reconstruction, Dictionaries, Mathematical model, Fingerprint recognition, Phantoms, Magnetic resonance. Abstract: In MR Fingerprinting (MRF), balanced Steady-State Free Precession (bSSFP) has advantages over unbalanced SSFP because it retains the spin history achieving a higher signal-to-noise ratio (SNR) and scan efficiency. However, bSSFP-MRF is not frequently used because it is sensitive to off-resonance, producing artifacts and blurring, and affecting the parametric map quality. Here we propose a novel Spatial Off-resonance Correction (SOC) approach for reducing these artifacts in bSSFP-MRF with spiral trajectories. SOC-MRF uses each pixel’s Point Spread Function to create system matrices that encode both off-resonance and gridding effects. We iteratively compute the inverse of these matrices to reduce the artifacts. We evaluated the proposed method using brain simulations and actual MRF acquisitions of a standardized T1/T2 phantom and five healthy subjects. The results show that the off-resonance distortions in T1/T2 maps were considerably reduced using SOC-MRF. For T2, the Normalized Root Mean Square Error (NRMSE) was reduced from 17.3 to 8.3% (simulations) and from 35.1 to 14.9% (phantom). For T1, the NRMS was reduced from 14.7 to 7.7% (simulations) and from 17.7 to 6.7% (phantom). For in-vivo, the mean and standard deviation in different ROI in white and gray matter were significantly improved. For example, SOC-MRF estimated an average T2 for white matter of 77ms (the ground truth was 74ms) versus 50 ms of MRF. For the same example the standard deviation was reduced from 18 ms to 6ms. The corrections achieved with the proposed SOC-MRF may expand the potential applications of bSSFP-MRF, taking advantage of its better SNR property. |
14,819 | Please write an abstract with title: Lossless Discrete Atomic Compression of Full Color Digital Images, and key words: Privacy, Image coding, Image color analysis, Digital images, Conferences, Distortion, Image reconstruction. Abstract: In this paper, we consider discrete atomic compression (DAC) of full color digital images. DAC is a lossy compression algorithm. We show that lossless compression can be provided without significant changes of this algorithm. The main idea is to add compressed information about differences between the source image and the reconstructed one to the corresponding DAC-file. These data in combination with “lossy” part of DAC-file provide reconstruction of the image without any distortions. Also, we investigate efficiency of such an approach. |
14,820 | Please write an abstract with title: A design and complement for face recognition, and key words: Face recognition, Pixel, Neural networks, Pattern recognition, Image resolution, Principal component analysis, Image recognition, Fingerprint recognition, Humans, Computer science. Abstract: Based on the face orientation, a system for face recognition is designed. BP neural network is used for face orientation recognition and a subnet with a set of single export is replaced with formerly BP neural network to increase the accuracy of face orientation recognition. The face recognition with the principal components analysis based on classification of face orientation shows the accuracy of face recognition is increased. |
14,821 | Please write an abstract with title: Compression and Analysis of Ultrasonic Doppler Blood Flow Meter Data by the Discrete Chebyshev Transform, and key words: Chebyshev approximation, Blood, Springs, Doppler effect, Electromagnetics, Transforms, Photonics. Abstract: The new scheme to ultrasonic Doppler blood flowmeter (DBF) signals compression through the Discrete Chebyshev Transform (DChT) is developed. The first kind Chebyshev polynomials of up to the 256th order are used for high quality approximation. These polynomials have interesting properties that make them very attractive for the tasks of the optimal polynomials interpolation. The compression mechanism consists of the following steps: segmentation, decomposition into the basis of Chebychev polynomials, and selection of only those that are less than a certain threshold. Modifying the threshold, we can adjust the compression ratio. There are no restrictions on the location of the characteristic waves inside a DBF block. Thus, segmentation within multiple cardiocycles can be performed arbitrarily, but it is only necessary to determine the length of the block. The performance of the proposed method is evaluated with the parameters of compression ratio (CR) and Percent Root square Difference (PRD). The method is very fast that makes it useful in the data communication in telemedicine. The results obtained are optimistic in terms of DBF signal reconstruction error at given compression rates. Additionally, with our processing, the redundant data stream could be reduced to the most significant parameters that could efficiently contribute to medical decision making. |
14,822 | Please write an abstract with title: Reducing energy of digital multiplier by adjusting voltage supply to multiplicand variation, and key words: Voltage, Circuits, Delay, Energy consumption, Digital signal processing, Discrete cosine transforms, Energy dissipation, Optimization methods, Clocks, Computer science. Abstract: This paper proposes a novel architectural technique to reduce power consumption of digital multipliers. Unlike related approaches which focus on multiplier transition activity, we concentrate on reduction of supply voltage. Two implementation schemes capable of dynamically adjusting a double voltage supply to input data variation are presented. Simulations show that the schemes can reduce energy consumption of 16 /spl times/ 16 bit multiplier by 33.4% and 25.2% on average without any speed degradation and as low as 4.7% area overhead. |
14,823 | Please write an abstract with title: Circuit Partitioning optimization using Parallel refinement algorithm, and key words: Partitioning algorithms, Optimization, Very large scale integration, Instruction sets, Parallel processing, Integrated circuit modeling, Frequency modulation. Abstract: Circuit partitioning is a major step in workload distribution for parallel computing system and CMOS VLSI circuit design. Circuit partitioning involves graph partitioning for effective utilization of available CPU power in case of higher number of cores per processor. It improves the degree of partition and amount of parallelism requirement of the partition. In this paper, we propose a shared memory parallel double way method of refinement of current partitioning which can break the local minima. The proposed method shows superiority in comparison to exiting serial refinement methods and achieves speed up of 1.2× to 24.5×24 threads while revealing only .37% higher edge cuts in comparison to serial run. |
14,824 | Please write an abstract with title: Bluetooth and Wi-Fi wireless protocols: a survey and a comparison, and key words: Bluetooth, Wireless application protocol, Communication standards, Wireless communication, Energy consumption, Physical layer, Media Access Protocol, Joining processes, Communication cables, Network topology. Abstract: Bluetooth and IEEE 802.11 (Wi-Fi) are two communication protocol standards that define a physical layer and a MAC layer for wireless communications within a short range (from a few meters up to 100 m) with low power consumption (from less than 1 mW up to 100 mW). Bluetooth is oriented to connecting close devices, serving as a substitute for cables, while Wi-Fi is oriented toward computer-to-computer connections, as an extension of or substitution for cabled LANs. In this article we offer an overview of these popular wireless communication standards, comparing their main features and behaviors in terms of various metrics, including capacity, network topology, security, quality of service support, and power consumption. |
14,825 | Please write an abstract with title: Auto-tunable microlens chip for sensing applications, and key words: Lenses, Microoptics, Polymers, Actuators, Thermal force, Packaging, Thermal lensing, Thermal sensors, Thermal expansion, Force sensors. Abstract: An integrated auto-tunable microlens chip, which is capable of adjusting its focal length over a wide range, is reported. The packaged microlens chip consists of a flexible 3D convex polymer lens, thermal actuator and sensor. The actuation mechanism based on the liquid's thermal expansion is introduced for the first time ever into an auto-tunable microlens to obtain relatively large actuation force and displacement. The 3D convex polymer lens provides an initial focal point at no actuation. The focal length change is controlled by varying the voltage applied to the thermal actuator and without any mechanical moving parts. It varies from 9.197 to 2.619 mm, which corresponds to the change of numerical aperture from 0.146 to 0.448. Potential applications include single cell detection and immobilization, optical sensor, lab-on-a-chip, ophthalmologic mimetic system, high throughput scanning and confocal imaging system. |
14,826 | Please write an abstract with title: A Comparative Study of Machine Learning Models for COVID-19 prediction in India, and key words: COVID-19, Predictive models, Regression tree analysis, Support vector machines, Mathematical model, Machine learning, Viruses (medical). Abstract: Machine learning is commonly being used in every field. Forecasting systems based on machine learning (ML) have shown their importance in interpreting perioperative effects to accelerate decision-making on the potential course of action. In several technology domains, ML models have been used long to define and prioritize adverse threat variables. To manage forecasting challenges, many prediction approaches are widely used. The paper shows the ability of ML models to estimate the amount of forthcoming COVID-19-affected patients that is now considered a serious threat to civilization. In paper this, we have performed a comparative study of five machine learning standard models like Linear regression (LR), decision tree, least absolute shrinkage and selection operator (LASSO), random forest and support vector machine (SVM) to forecast the threatening variables of COVID-19. Each of the models makes three forms of forecasts, i.e. the total active cases, the total deaths, and the total recoveries in the next five days. The findings provided by the paper suggest that the use of these techniques for the current COVID-19 the pandemic scenario is a promising strategy. For better accuracy, we have used a six-degree polynomial. Experiment results illustrate that poly LR and poly LASSO gives the best results followed by LR, LASSO, random forest, and decision tree. SVM shows the poor result in the prediction of COVID-19. |
14,827 | Please write an abstract with title: Accurate 3D Reconstruction from Circular Light Field Using CNN-LSTM, and key words: Three-dimensional displays, Two dimensional displays, Trajectory, Cameras, Geometry, Reliability. Abstract: A light field is formed by densely capturing images on a regular sub-aperture grid. Geometry information endowed in the epipolar plane images(EPI) can only lead to a 2. 5D reconstruction. In order to obtain a full 360°view of an object, we focus on light fields captured by a circularly moving camera, resulting in circular light fields (or Cir-LFs in short). Compared with traditional EPIs, Circular EPIs(CEPIs) provide unique advantages, such as that corresponding points forming a 3D sinusoid like curve instead of a 2D straight line and geometry information encoded sequentially in multiple adjacent views along the curve. However, current reconstruction methods only focus on the 2D projection of 3D curve, leading to distortions in the reconstructed upper and lower surfaces. We propose to analyze 3D features contained in the 3D CEPI volume and we develop a deep CNN-LSTM network to model the gradient map in the CEPI volume. Additionally, a large scale Cir-LF dataset is constructed for research purpose. Experiments on both synthetic and real scenes demonstrate the effectiveness and generaliability of the proposed method. |
14,828 | Please write an abstract with title: Economic benefits of optical transport layer reconfigurability and tighter coupling with the service layer, and key words: Optical coupling, Optical fiber networks, Protection, Bandwidth, Aggregates, Costs, Optical switches, Optical add-drop multiplexers, Fluid dynamics, Content management. Abstract: With the introduction of fast reconfigurable optical node elements and automatic configurability via signaling, the optical transport layer has become a very dynamic entity. This agility enables capital and operational savings, e.g., due to more efficient utilization of in-place resources, as well as new revenue generating service opportunities, like bandwidth on demand. Additionally, there can be substantial benefits in using the optical layer for restoration. We examine the benefits of optical layer dynamic reconfigurability, especially when there is greater coupling between a packet data service layer (taken here to be IP/MPLS for concreteness) and optical transport layer. We compare failure restoration using only the service layer to various alternatives involving the transport layer, with and without optical layer reconfigurability. We also consider orchestrated restoration between the data and optical transport layers, and propose a joint restoration mechanism. In single-layer restoration paradigms, we find that IP layer restoration is more cost-effective at lower aggregate traffic levels for link failures but, as traffic scales, optical layer restoration is more cost-effective. In multilayer protection paradigms, we find that overlaying joint router protection on transport layer link protection permits strong synergy of protection capacity reuse, thus leading to significant cost savings for operators. |
14,829 | Please write an abstract with title: Efficient Allocation of Intelligent Surfaces in Programmable Wireless Environments, and key words: Wireless networks, Conferences, Layout, Quality of service, Grasping, Reconfigurable intelligent surfaces, Data models. Abstract: Next-generation wireless networks rely on unused high spectrum bands, such as mmWave and visible light, to support high-speed communications. However, such bands suffer from frequent outages of line-of-sight (LoS) signals, which deteriorates the communication's quality. Thus, recent efforts have promoted programmable wireless environments (PWEs), which employs reconfigurable intelligent surfaces (RIS) that can redirect non-LoS (NLoS) signals towards the user to enhance reception quality. Unfortunately, these efforts are limited so far to setups with stationary users. We show in this paper that crowd mobility induces spatio-temporal sparseness across the wireless channels in an indoor layout. As a result, shadowed regions will exist on the walls of the room due to signal blockage. Hence, random allocations of passive RIS tiles across the room will not result in the utmost gains and will unnecessarily complicate the communication system. Therefore, we propose an efficient data driven approach that capitalizes on a realistic indoor mobility model to allocate RIS tiles across the room in a way that maximizes their exploitation efficiency. Our results indicate that efficient design of PWEs can reduce the number of required passive RIS tiles by 70% while maintaining high service quality. |
14,830 | Please write an abstract with title: Detection of Underwater Marine Plastic Debris Using an Augmented Low Sample Size Dataset for Machine Vision System: A Deep Transfer Learning Approach, and key words: Training, Economics, Machine vision, Transfer learning, Ecosystems, Distance measurement, Plastics. Abstract: Waste in aquatic environments devastates aquatic habitats and offers a tall environmental and economical risk. Machine Vision might play a role in resolving this issue by detecting and finally eliminating debris. Using an augmented low sample size from a publicly available collection of underwater plastic waste, this research employed a YOLOv3 deep-learning system to visually recognize debris in realistic underwater environments. The detection model has a training and validation accuracy of 98.026 % and 94.582 %, respectively, according to the study's findings, with an mAP value of 98.15%. With its effectiveness in detecting underwater plastic waste, the recommended model is suitable for a variety of machine vision systems. The system has a 100% testing accuracy, with detection per frame accuracy ranging from 60.59% to 98.89%. |
14,831 | Please write an abstract with title: Comparing MFCC and MPEG-7 audio features for feature extraction, maximum likelihood HMM and entropic prior HMM for sports audio classification, and key words: Feature extraction, Hidden Markov models, Mel frequency cepstral coefficient, MPEG 7 Standard, Maximum likelihood estimation, Cepstrum, Acoustic noise, Laboratories, Electronic mail, Ear. Abstract: We present a comparison of 6 methods for classification of sports audio. For the feature extraction we have two choices: MPEG-7 audio features and Mel-scale frequency cepstrum coefficients (MFCC). For the classification we also have two choices: maximum likelihood hidden Markov models (ML-HMM) and entropic prior HMM (EP-HMM). EP-HMM, in turn, has two variations: with and without trimming of the model parameters. We thus have 6 possible methods, each of which corresponds to a combination. Our results show that all the combinations achieve classification accuracy of around 90% with the best and the second best being MPEG-7 features with EP-HMM and MFCC with ML-HMM. |
14,832 | Please write an abstract with title: Method of Systematic Literature Review for Internet of Things in ZigBee Smart Agriculture, and key words: Agriculture, ZigBee, Internet of Things, Wireless sensor networks, Intelligent sensors, Libraries. Abstract: Lately, utilization of Wireless Sensor Network (WSN) technology is increasing and widely applied in various fields. WSN is currently applied for Internet of Things (IoT)-based agriculture. An example of WSN technology is ZigBee. ZigBee provides irrigation control, climate monitoring and food chain control systems. To support all mentioned systems, ZigBee's IoT supports communication among available sensors. By having communication, ZigBee is expected to improve productivity and predict agriculture problem. The paper will use Systematic Literature Review (SLR) to give an overview that IoT has potential for agriculture. This is because IoT can help every farmer during operational on food and livestock production. |
14,833 | Please write an abstract with title: Parallel Multiobjective Feature Selection for Binary Classification, and key words: Global Positioning System, Feature extraction, Hafnium compounds, Task analysis, Optimization, Parallel processing, Sociology. Abstract: Feature selection has become a prominent step for many research studies as available data increases continuously with the advances in technology. The objective of feature selection is two-fold: minimizing the number of features and maximizing learning performance. Therefore, it requires a multiobjective optimization. In this study, we utilize the multicore nature of a regular PC in the feature selection domain. For this purpose, we build three models that exploit the parallel processing capability of a modern CPU. We execute the feature selection task on a single processor in the first model as a baseline. In other models, we execute the feature selection task in four cores of the CPU, in parallel. Specifically, in the second model, we decrease the population size per processor and explore whether we can achieve comparable solution sets in less amount of time. The third model preserves the population size and explores a more extensive search space. We compare the results of these models in terms of accuracy, number of features and execution time. Experiment results show that parallel processing in the feature selection domain leads to faster execution and better feature subsets. |
14,834 | Please write an abstract with title: Electronic gears for electric vehicles with wheel motor, and key words: Gears, Electric vehicles, Wheels, Batteries, Propulsion, Assembly, Torque, Vehicle driving, Electronic equipment testing, State estimation. Abstract: A novel electronic gearing is proposed in the propulsion system for an electric vehicle driven directly by a wheel motor. This electronic gearing assembles the parallel and serial connections of batteries and motor windings into four gears to accommodate various driving patterns in the permissible range of speed and torque. The objectives of this invention are to extend the speed range of constant power, as well as to improve the driving performance and efficiency of the vehicle. The proposed electronic gearing is tested on a dynamometer to simulate the ECE40 driving pattern, and the driving range is estimated by measuring the state-of-charge of lead-acid batteries, which are normally used as the power source of electric vehicles. The experimental results show that the efficiency increases in terms of the driving range of electric vehicles. |
14,835 | Please write an abstract with title: Smart transformer/large flexible transformer, and key words: Topology, Power grids, Voltage control, Power quality, Stability criteria, Power system stability, Load flow control. Abstract: Solid-state transformer-based smart transformer (ST) can provide the dc connectivity and advanced services to improve the grid performance and to increase the penetration of the power electronics interfaced resources (e.g., distributed generators and electric vehicle charging stations) in modern electricity distribution grids. Since the ST is a new and effective paradigm of the electricity grid evolution to well understand the ST, this paper systematically presents the basic architecture and the typical control schemes of the ST and then the advanced services that ST can provide to improve the electricity grids performances in terms of the power flow control, power quality improvement, active damping and active contribution to improve distribution grid resilience by means of enabling autonomous microgrids operation as well as launching a restoration procedure following a general blackout. |
14,836 | Please write an abstract with title: Health Condition Assessment for Pumped Storage Units Using Multihead Self-Attentive Mechanism and Improved Radar Chart, and key words: Vibrations, Degradation, Vibration measurement, Monitoring, Radar, Informatics, Upper bound. Abstract: A novel health assessment method for pumped storage units (PSUs) is presented in this article. First, multihead self-attentive mechanism (MSM) combined with quantile regression neural network (QRNN) are proposed to establish a health benchmark model for PSUs to reveal the intricate relationship between the vibration and its multiple influencing factors. Especially, MSM automatically learns the complex interaction features among multiple influencing factors, while QRNN explores the upper bounds of health vibration under specific operational parameters. Then, a fuzzy dimensionless function is constructed to map the deviation of the currently measured vibration from the predicted health vibration to the performance degradation indexes. Finally, an improved radar chart method is proposed to visually illustrate the health condition of multiple measurement locations and give comprehensive health assessment for PSUs. The proposed method is applied in a PSU in Zhejiang province of China. The results of comparative experiments illustrate its effectiveness and feasibility. |
14,837 | Please write an abstract with title: Joint Radar-Communication System Design via FH Code Selection and PSK Modulation, and key words: joint radar-communication system, waveform diversity, frequency hopping, phase shift keying. Abstract: A joint radar-communication system is an integrated platform which implements radar and communication function simultaneously. This duality provides an effective way to alleviate the problem of increasingly tensive spectrum congestion. In this paper, we consider a dual functional signal designing method for a joint system embedding communication information into radar radiation. Contrary to previous waveform design methods that embed communication symbols on permutations of frequency-hopping (FH) codes, the proposed information-embedding scheme utilizes the FH code selection and phase shift keying (PSK) modulation jointly to accomplish waveform diversity. Benefiting from the joint implementation of frequency modulation and phase modulation within each subpulse, the proposed scheme greatly increases the bandwidth efficiency. Simulation results demonstrate that the proposed information-embedding scheme achieves a high data transmission rate and shows great symbol error performance at the expense of radar performance. |
14,838 | Please write an abstract with title: Investigation of the Thermophysical Processes in Highly Thermally Conductive Composite Material with a Complex Structure, and key words: Heating systems, Insulation, Composite materials, Stator windings, Conductivity, Thermal conductivity, Generators. Abstract: The most effective reduction of the heating level in the stator winding is carried out by reducing the temperature differences over the thickness of the main insulation. One of the key solutions of this problem is realized through increasing the thermal conductivity of the main insulation. In this paper, the authors consider the main insulation of the stator winding of turbine generator and discusses the optimization of the insulation tape design. The approach was developed to evaluate each component contribution of the composite tape to the equivalent thermal conductivity and for determining the direction of further upgrades focused on significant design changes to the object of study. The authors have developed parametric simulation tools by using Ansys Parametric Design Language. |
14,839 | Please write an abstract with title: An investigation of beam focusing perturbations in THz spectroscopy measurements, and key words: Spectroscopy, Focusing, Absorption, Refractive index, Laser beams, Frequency measurement, Performance evaluation, Optical pumping, Optical refraction, Optical variables control. Abstract: We present evidence that THz spectroscopy measurements performed using a focused beam result in an increase of calculated sample refractive index, compared to that measured under plane wave conditions. No significant differences were found in sample absorption properties. |
14,840 | Please write an abstract with title: A Low Noise Single-Ended GaAs Schottky FET Amplifier for a 14 GHz Satellite Communication Application, and key words: Gallium arsenide, FETs, Low-noise amplifiers, Satellite communication, Noise figure, Circuit noise, Scattering parameters, Circuit testing, Laboratories, Communication industry. Abstract: A 14.0 - 14.5 GHz amplifier consisting of a cascade of three single-ended stages which realizes a noise figure of 3.5 dB and a gain of 17 dB has been designed. This has been achieved with a new design technique which is tolerant of changes in F ET S-parameters and yet capable of extracting the maximum performance of the device. Results on a 10 GHz amplifier designed with the above technique will also be given. |
14,841 | Please write an abstract with title: Shipboard microgrids: comparison of solutions based on LVDC distribution on cruise ships, and key words: Low voltage, Power distribution, Fuel cells, Europe, Hybrid power systems, Batteries, Marine vehicles. Abstract: DC shipboard power distribution offers several advantages over conventional AC-based solutions and nowadays a large amount of research activities is underway to accomplish an extensive and de-risked use of DC on board. In this paper, two solutions, involving low voltage (LV) DC distribution on board, are proposed and compared with the currently used shipboard AC scheme. In particular, two hybrid AC/DC LV architectures are considered, one relying on the centralized ship generation, typical of the integrated power systems (IPSs), and the other relying on a decentralized generation, based on fuel cells (FCs) and batteries. The comparison allowed to evaluate the advantage of the hybrid architectures in terms of electrical plant equipment’s weight and volume reduction. A real-world cruise ship has been examined as case study |
14,842 | Please write an abstract with title: A suboptimal detection scheme for MIMO systems with nonbinary constellations, and key words: MIMO, Maximum likelihood detection, Transmitting antennas, Detectors, Decision feedback equalizers, Maximum likelihood estimation, Detection algorithms, Receiving antennas, Performance loss, Signal to noise ratio. Abstract: For multiple-input multiple-output (MIMO) spatial multiplexing systems the complexity of the maximum likelihood detector (MLD) can be prohibitively extensive when the number of transmitting antennas and constellation points is high. To simplify the MLD many linear and nonlinear techniques have been proposed. In this paper the principle of reduced state sequence detection, based on mapping by set partitioning, is applied to perform detection in MIMO systems. Simulation results are presented for the proposed suboptimal detection algorithm. |
14,843 | Please write an abstract with title: Miniaturized Navigation Grade Quartz Vba Accelerometer For Space Applications, and key words: Accelerometers, Navigation, Inertial sensors, Europe, Sensor systems, Reliability, Qualifications. Abstract: This paper demonstrates that modified navigation grade accelerometers are good candidates for space applications. This is the response to an increasing demand for high performance inertial sensors in new space applications. Improvement of this product is an ongoing effort to make small sensors reliable in even more demanding applications, such as Pioneers [1] and Eurisa [2] European projects. |
14,844 | Please write an abstract with title: High Q shielded dielectric resonator - the basis of stable MM-waves generator, and key words: Oscillators, Frequency, Q factor, Whispering gallery modes, Gunn devices, Diodes, Stability, Tuning, Dielectric measurements, Power measurement. Abstract: High Q-factor whispering gallery modes which are excited in a shielded hemispherical dielectric resonator by an external signal or Gunn diode are investigated. Their application as modes of an oscillator with high frequency stability is proposed. The power of the output signal and frequency tuning of an oscillator based on the investigated resonator are measured. |
14,845 | Please write an abstract with title: AFORS-HET: a computer-program for the simulation of heterojunction solar cells to be distributed for public use, and key words: Distributed computing, Computational modeling, Computer simulation, Heterojunctions, Photovoltaic cells, Numerical simulation, Internet, Semiconductivity, Boundary conditions, Equations. Abstract: We offer a numerical simulation tool, AFORS-HET, for public use, which allows to model homo- as well as heterojunction devices. AFORS-HET is the short form of automat for simulation of heterostructures and can be downloaded via the internet: http://www.hmi.de/bereiche/SE/SE1/projects/aSicSi/AFORS-HET. An arbitrary sequence of semiconducting layers can be modelled. A variety of boundary conditions can be chosen. The program solves the one dimensional semiconductor equations in steady-state and for small sinusoidal ac-perturbations. Furthermore, a variety of common characterisation techniques have been implemented, current-voltage (I-V), internal quantum efficiency (IQE), impedance, capacitance (CV, CT), static surface photovoltage (SPV), electron beam induced current (EBIC) and photoluminescence (PL). A user-friendly interface allows to easily perform parameter variations, and to visualise and compare your simulations. |
14,846 | Please write an abstract with title: A framework for process change, and key words: Manufacturing. Abstract: Forces such as technology change and increased competition provide opportunities and challenges that drive a firm to continuously evaluate and modify its resource capabilities. As a consequence, a firm's process change strategy is of paramount importance for sustained manufacturing success. However, fundamental elements of process change strategy are not well understood. Long term performance benefits associated with potential process change alternatives are often unclear. Moreover, uncertainty exists regarding the actual benefits that may be attained from various types of process change. Critical issues impacting the proper implementation of process change are frequently underestimated or largely ignored. Therefore, despite the improved performance sought, process change often leads to lower productivity, excessive equipment downtime, and deterioration in quality. As the authors review the relevant empirical and normative literature, a framework emerges that characterizes the salient features of a firm's process change strategy. The underlying dynamics of process change are explored and strategies are discussed to reduce the short-term disruption and enhance the long-term gain. In particular, the authors demonstrate the importance of creating and applying knowledge to improve the outcome of process change. They describe managerial actions that can be taken to reduce various sources of uncertainty associated with process change. Moreover, they identify key contributions as well as limitations of the existing normative literature on process change. Insights from the empirical literature are given that both support elements of the existing normative models and provide direction for future normative research. Thus, the authors seek to aid practicing managers and researchers alike to better understand the full scope and implications of process change. |
14,847 | Please write an abstract with title: W-SRAT: Wavelet-based Software Reliability Assessment Tool, and key words: Maximum likelihood estimation, Software algorithms, Noise reduction, Estimation, Web pages, Software quality, Prediction algorithms. Abstract: Wavelet shrinkage estimation is a non-parametric technique to estimate the non-homogeneous Poisson process (NHPP)-based software reliability growth model (SRGM), and provides better goodness-of-fit performances than the common parametric approach by means of the maximum likelihood estimation. However, it has a serious drawback that not only the long-term prediction but also the quantification of software reliability for an arbitrary testing/operational period were difficult. In this paper we propose a long-term prediction approach for the NHPP-based SRGM with the wavelet shrinkage estimation, where several denoising and data transform techniques are applied to estimate the NHPP discrete intensity function. We develop a wavelet-based software reliability assessment tool; WSRAT, to enable a lightweight and automatic software reliability prediction, in addition to implement the existing denoising and data transform techniques. W-SRAT is a unique software reliability assessment tool based on the wavelet shrinkage estimation, and is a web-based freeware to predict the cumulative number of software faults and the quantitative software reliability. We demonstrate how to use the W-SRAT in actual software reliability management. |
14,848 | Please write an abstract with title: Diagonal and Alamouti Space-Frequency Coded Quadrature Index Modulation, and key words: Diversity reception, OFDM, Codes, Indexes, Modulation, Frequency-domain analysis, Transmitting antennas. Abstract: In this letter, a new diagonal and Alamouti space-frequency coded quadrature index modulation (DASFC-QIM) scheme for MIMO-OFDM systems is proposed to achieve higher transmit diversity. In the proposed DASFC-QIM scheme, firstly two modulated symbols are associated through a Hadamard matrix and a rotation matrix to construct a diagonal code. Next, by independently selecting the indices of the space-frequency units in each resource block (RB) twice, the in-phase and the quadrature components of the diagonal code are put into each RB. Finally, the signal in each RB is divided into two parts which are used to construct an Alamouti space-frequency code fitting for four transmit antennas. It can be proved that the DASFC-QIM scheme achieves the fourth order transmit diversity so that it achieves better bit error rate (BER) performance than some existing typical IM schemes. Simulation results show that DASFC-QIM exhibits superior BER performance over both the independent and correlated Rayleigh fading channels. |
14,849 | Please write an abstract with title: Average Age in Coordinate Decision-Making Wireless Systems Operating with FBL Codes, and key words: Wireless communication, Monte Carlo methods, Codes, Error probability, Error analysis, Decision making, Decoding. Abstract: Future Internet of Things (IoT) networks are expected to support low-latency communications, where transmissions are usually operating with finite blocklength (FBL) codes to satisfy the latency requirements. In such FBL regime, the packet decoding error probability becomes nonnegligible even if the coding rate is lower than the Shannon capacity, which requires a random number of retransmissions to achieve the reliability requirement. This actually introduces random (re)transmission delays to the packets, which makes the age/delay model characterization of such networks becomes interesting and challenging, especially for networks using the data packets for latency-sensitive decision-making. In this work, we consider an M/M/1/M update-and-decide system with two independent sources and estimate the timeliness of those received packets used for decisions. We measure the freshness (i.e., the age) of the received updates at decision epochs by using the age upon decisions (AuD). For multi-source system, coordinate decisions would be made based on the AuDs of updates from each source. Under the First-come-First-served (FCFS) policy, we derive the closed form expression for average AuD of each source and the average ages of coordinate decisions. We show that the average AuD of each source is large when its arrive rate is relatively large or small, and will be larger with the increasing of another source's packets generation rate. We also show that the age of coordinate decisions will achieve the minimum, when the total arrive rate of the system is approximately equal to the service rate. Our obtained results are also validated by Monte Carlo results. |
14,850 | Please write an abstract with title: RIS-Assisted Device Activity Detection With Statistical Channel State Information, and key words: Device activity detection, reconfigurable intelligent surface, coverage extension, grant-free uplink, statistical channel state information, phase-shift design. Abstract: This paper studies reconfigurable intelligent surface (RIS)-assisted device activity detection for grant-free (GF) uplink transmission in wireless communication networks. In particular, we consider mobile devices located in an area where the direct link to an access point (AP) is blocked. Thus, the devices try to connect to the AP via a reflected link provided by an RIS. Therefore, for the RIS, a phase-shift design is desired that covers the entire blocked area with a wide reflection beam because the exact locations and times of activity of the devices are unknown in GF transmission. In order to study the impact of the phase-shift design on the device activity detection at the AP, we derive a generalized likelihood ratio test (GLRT) based detector and present an analytical expression for the probability of detection, which is a function of the channel statistics and the phase-shift design. Assuming knowledge of statistical channel state information (CSI), we formulate an optimization problem for the phase-shift design for maximization of the guaranteed probability of detection for all locations within a given coverage area. To tackle the non-convexity of the problem, we propose two different approximations of the objective function and an algorithm based on the majorization-minimization (MM) principle. The first approximation leads to a design that aims to reduce the variations of the end-to-end channel while taking system parameters such as transmit power, noise power, and probability of false alarm into account. The second approximation can be adopted for versatile RIS deployments because it only depends on the line-of-sight (LoS) component of the end-to-end channel and is not affected by system parameters. For comparison, we also consider a phase-shift design maximizing the average channel gain and a baseline analytical phase-shift design for large blocked areas. Our performance evaluation shows that the proposed approximations result in phase-shift designs that guarantee a high probability of detection across the coverage area and outperform the baseline designs. |
14,851 | Please write an abstract with title: Calculating the effective capacitance for the RC interconnect in VDSM technologies, and key words: Capacitance, Propagation delay, Integrated circuit interconnections, Delay effects, Switches, Piecewise linear approximation, Voltage, Application specific integrated circuits, Libraries, Design engineering. Abstract: In this paper, we present a new technique for calculating an effective capacitance of an RC interconnect line in very deep submicron design technologies. The calculation scheme guarantees that the effective capacitance model simultaneously matches both the 50% propagation delay and the 0-to-0.8 V/sub dd/ output transition behavior of a standard cell driving an RC interconnect. Experimental results show that the new technique exhibits high accuracy (less than 5% error) and high efficiency (converges in two or at most three iterations). The paper also includes extensions to handle complex cells as drivers of the RC interconnect. |
14,852 | Please write an abstract with title: An expert mill cutter selection system, and key words: Milling machines, Expert systems, Cost function, Productivity, Geometry, Power system modeling, Cutting tools, Machining, Process planning, Manufacturing. Abstract: This paper discusses the selection of tools in milling operations. To carry out this research, it has been developed an expert system hinged on numerical methods. The knowledge base is given by limitations in process variables, which let us to define the allowable cutting parameter space. The mentioned process variables are, instabilities due to tool-work-piece interaction, knowing as chatter vibration, and the power available in the spindle motor. Then, a tool cost model is contrived. It is used to choose the suitable cutting tool, among a known set of candidate available cutters, and to obtain the appropriate cutting parameters, which are the expert system outputs. An example is presented to illustrate the method |
14,853 | Please write an abstract with title: Experience curve approach for more effective policy instruments, and key words: Instruments, Marketing and sales, Europe, Production facilities, Costs, Large-scale systems, Potential energy, Solar energy, Monitoring. Abstract: The price evolution of PV systems in Europe shows that a significant reduction is achieved for modules and the BOS of small rooftop grid connected systems. The learning rate is 20%, consistent with other studies. The module price has stabilised the last years, as market conditions had a large effect. It is expected that recently built and planned module production facilities will give an increased cost reduction. For rooftop systems the market that has been created in the last decade will lead to more standardisation and integration in the building sector, leading to lower prices, but also more application. |
14,854 | Please write an abstract with title: Enhancement of interaction efficiency in diffraction radiation oscillator, and key words: Diffraction, Oscillators, Indium tin oxide, Helium, Electronic mail, Bills of materials, Milling machines, Chromium. Abstract: The output characteristics of the diffraction radiation oscillator with small-volume open resonator are examined. |
14,855 | Please write an abstract with title: A 128K wordx8 bit dynamic RAM, and key words: DRAM chips, Capacitance, Aluminum, Random access memory, Wiring, Testing, Circuit noise, Coupling circuits, Wires, Power dissipation. Abstract: A 1-Mb DRAM with 128K/spl times/8 bit organization is described. In designing the circuit, half V/SUB cc/ bit line precharge with dummy reverse circuits was adopted for noise reduction. The noise is estimated using a three-dimensional capacitance calculation. In realizing the chip, a 1-/spl mu/m NMOS process with double-level aluminum wiring was used. |
14,856 | Please write an abstract with title: Tight-Pitched 10 μm-Width Solder Joints for c-2-c and c-2-w 3D-Integration in NCF Environment, and key words: Resistance, Semiconductor device measurement, Kelvin, Stacking, Electronic components, Flip-chip devices, Electrical resistance measurement. Abstract: Solder micro-joint (μ-joint) fenced with non-conducting film (NCF) under tight pitch configuration has been studied for its thermal and electrical stability after chip-to-chip and chip-to-wafer integaration via thermal cycle (TC) test and Kelvin measurement under constant-current-stressing (CCS). For the optimized flip-chip bonding parameters, we have obtained 28-30 mΩ resistance for a single Cu-SnAg μ-joint of 10 μm in size at 20 μm pitch configuration. We hardly observed any change in the μ-joint resistance after 500 cycles of TC test as well as CCS for 100 ksec at 100 °C. Both the TC and the CCS results confirm that 10 μm-sized solder μ-joints fenced with NCF under tight-pitched configuration were successfully formed for 3-D chip stacking applications. |
14,857 | Please write an abstract with title: Query planning for the grid: adapting to dynamic resource availability, and key words: Availability, Data analysis, Educational institutions, Query processing, Data processing, Memory, Analytical models, Drives, Computer science, Sensor phenomena and characterization. Abstract: The availability of massive datasets, comprising sensor measurements or the results of scientific simulations, has had a significant impact on the methodology of scientific reasoning. Scientists require storage, bandwidth and computational capacity to query and analyze these datasets, to understand physical phenomena or to test hypotheses. This paper addresses the challenge of identifying and selecting resources to develop an evaluation plan for large scale data analysis queries when data processing capabilities and datasets are dispersed across nodes in one or more computing and storage clusters. We show that generating an optimal plan is hard and we propose heuristic techniques to find a good choice of resources. We also consider heuristics to cope with dynamic resource availability; in this situation we have stale information about reusable cached results (datasets) and the load on various nodes. |
14,858 | Please write an abstract with title: Effect of fast electron irradiation on the dielectric and pyroelectric response of radially-oriented PVDF film, and key words: Electrons, Dielectrics, Pyroelectricity, Polymers, Ferroelectric films, Temperature, Ferroelectric materials, Production, Paramagnetic resonance, Infrared spectra. Abstract: Radiation-induced functionalization of ferroelectric P(VDF/TrFE) copolymers was found to be effective in production of polymer relaxors attractive for applications. We studied radiation-induced changes in the dielectric relaxation and pyroelectric response of radially oriented PVDF film irradiated with electrons of energies 0.5-1.5 MeV. Radiation damage to the samples was characterized by ESR and IR spectroscopy. An increase in activation energy of segmental motion of the polymer and a downward shift of the freezing temperature of segmental motion and the Curie temperature, induced by electron irradiation, was related to a damage in all-trans conformation of the polymer chain and formation of polar regions. |
14,859 | Please write an abstract with title: Adaptive array of antennas and STAP, and key words: Adaptive arrays, Antenna arrays, Direction of arrival estimation, Radar detection, Parallel processing, Interference cancellation, Airborne radar, Blanking, Wideband, Directive antennas. Abstract: Summary form only given. The tutorial is divided into five parts: (1) sidelobe cancellers (SLC), (2) adaptive arrays, (3) additional topics on adaptive arrays, (4) space-time adaptive processing (STAP), and (5) parallel schemes for real-time implementation of STAP. |
14,860 | Please write an abstract with title: A Low-Complexity Handover Scheme Using Unsupervised Learning Techniques for 6G Multi-Networking, and key words: 6G, Handover, Internet of Things (loT), Light Fidelity (LiFi), Machine Learning (ML), Multi-Networking. Abstract: In the emerging 6G era, a multi-networking archi-tecture is crucial to satisfy the growing connectivity demands of resource-constrained loT devices. Additionally, employing higher frequency bands (mm Wave, THz, and optical spectrum) beyond sub-6 GHz is essential, yet it presents significant challenges. Poor propagation abilities and ultra-small cells of these higher-frequency networks amplify the complexity of mobility management. Therefore, devising an efficient hand over scheme for future ultra-dense 6G heterogeneous networks, capable of addressing these challenges and ensuring rapid response for loT devices, is of paramount importance. To address these challenges, we exemplify with the hybrid LiFi and WiFi network, which is regarded as a potential component for 6G heterogeneous networks, proposing an unsupervised learning-based handover scheme. Our simulations show that this scheme matches or surpasses benchmark performances in terms of user throughput, handover rate, and delay, while minimising computational complexity. Consequently, our approach effectively addresses the distinctive demands of future 6G loT environments. |
14,861 | Please write an abstract with title: Work in progress: Multiprotocol System for Learning Industrial Communications, and key words: Industries, Protocols, Automation, Conferences, Industrial communication, Programmable logic devices, Programming. Abstract: Many different communication protocols are used in the industry for automation activities. Here it is shown the experience of the last years related to how to prepare students towards facing this challenge, by teaching some widely used protocols and programming tools integrated in a final project that the students must solve in pairs. In addition, the assessment of the subject has been optimized towards increasing the implication of students in the different parts, something that has been studied by analyzing the evolution of the marks. |
14,862 | Please write an abstract with title: Equivalent Circuit Analysis of the Side-Coupled Cavity Structure, and key words: Cavity resonators, Couplings, Magnetic circuits, Equivalent circuits, Magnetic resonance, Integrated circuit modeling. Abstract: The resonating frequency associated with the side-coupled cavity (SCC) has been theoretically explored using an equivalent circuit approach. This study is focused to estimate the coefficient of magnetic coupling factor in the context of its structural parameters, which has so far been experimentally evaluated. This article also proposed an empirical formula to calculate the fundamental-mode frequency that includes the effect of the magnetic-coupling factor, which was not considered in the previously reported research. To support this research study, the SCC has been designed and simulated with the help of “CST Studio Suite.” The results obtained from the proposed empirical formula were compared with the simulation result so that theoretical analysis could be verified. After comparing the results, it was found that the relative error is below 1%, indicating that there is a good agreement between the results obtained from the theoretical and simulation techniques. |
14,863 | Please write an abstract with title: An optimal terminal guidance law, and key words: Optimal control, Missiles, Acceleration, Geometry, Automatic control, Aerodynamics, Differential equations, Computer vision, Proportional control, State estimation. Abstract: An optimal terminal guidance law is derived using linear optimal control theory. |
14,864 | Please write an abstract with title: Infrared Diffraction Radiation from Twin Dielectric Rods with Graphene Coatings as a Tool for Beam Position Sensing, and key words: Symmetric matrices, Diffraction, Graphene, Wires, Boundary conditions, Trajectory, Nanowires. Abstract: This work presents a research into the infrared range diffraction radiation (DR) of a modulated beam of charged particles moving between twin dielectric circular nanowires covered with graphene. The latter are assumed zero-thickness and characterized with the Kubo formalism and resistive-type boundary conditions. We assume that the beam velocity is constant and apply the separation of variables in the local coordinates, combined with the addition theorem for the cylindrical functions. This enables us to cast the problem of DR to a Fredholm second-kind matrix equation and, therefore, guarantees the convergence. Due to convergence, both far and near DR-field characteristics can be computed with a controlled accuracy. The analysis shows the appearance of additional resonances linked with a deviation of the beam trajectory from the symmetric position. “Shining” of these resonances can be viewed as an instrument for the beam position monitoring with a nanoscale antenna. |
14,865 | Please write an abstract with title: Effect of pulse jamming on IEEE 802.11 wireless LAN performance, and key words: Jamming, Wireless LAN, Physical layer, Laboratories, Traffic control, Wireless sensor networks, Multiaccess communication, Media Access Protocol, Internet telephony, Telecommunication traffic. Abstract: This paper investigates how the performance and capacity of the IEEE 802.11 medium access control (MAC) layer is affected by pulse jamming, using a time-driven simulation program in C language implemented at the Communications Laboratory of the Helsinki University of Technology. The simulations demonstrate the effect of pulse duration and pulse repetition internal on the IEEE 802.11 wireless local area network (WLAN) capacity, defined in terms of simultaneous voice over IP (VoIP) connections. Under normal conditions (i.e., no jamming), the WLAN can support a certain number of real-time VoIP connections, taking into account the fact that VoIP traffic cannot tolerate excessive delays caused by multiple retransmissions or the build-up of VoIP packets in the transmission buffers of the wireless stations. The simulations show that during severe pulse jamming, the number of supported VoIP connections is substantially decreased. |
14,866 | Please write an abstract with title: Reflection characteristics of a retrodirective PARC, and key words: Polarization, Optical reflection, Radar cross section, Anechoic chambers, L-band, Sensor arrays, Antenna measurements, Gain, Phased arrays, Frequency. Abstract: Reflection characteristics of a retrodirective PARC (polarimetric active radar calibrator) were measured in a radio anechoic chamber. The reflection beamwidth was twice as wide as that of a conventional array reflector of the same size, and the measured RCS was 40.8 dBm/sup 2/ that almost agreed with the predicted value of 41.5 dBm/sup 2/. |
14,867 | Please write an abstract with title: PCAT: PLC Command Analysis Tool for automatic incidence response in Water Treatment Plants, and key words: Integrated circuits, Representation learning, Actuators, Programmable logic devices, Process control, Big Data, Real-time systems. Abstract: A cyber-physical attack against critical infrastructures, such as water treatment and distribution plants, could lead to process anomalies. Several design and data centric approaches were developed to detect such anomalies when the physical processes of the underlying plant move from a normal to a malicious state. Although these approaches are necessary for the continued and reliable plant operation, they might not be sufficient to prevent service disruption or damage to components. This is because the impact of anomalies is already realized before the attack is detected. In this paper, we propose PCAT – PLC Command Analysis Tool that validates the control commands issued by the programmable logic controller (PLC). PCAT stops rogue attack commands before they reach the target actuators. In a case study, PCAT was deployed and validated on the operational water treatment plant named SWaT. The experimental results attest the performance of PCAT in ensuring the security, safety, and service status of the plant before it enters an anomalous state. |
14,868 | Please write an abstract with title: Federated Generalized Bayesian Learning via Distributed Stein Variational Gradient Descent, and key words: Bayes methods, Servers, Collaborative work, Uncertainty, Signal processing algorithms, Convergence, Training. Abstract: This paper introduces Distributed Stein Variational Gradient Descent (DSVGD), a non-parametric generalized Bayesian inference framework for federated learning. DSVGD maintains a number of non-random and interacting particles at a central server to represent the current iterate of the model global posterior. The particles are iteratively downloaded and updated by a subset of agents with the end goal of minimizing the global free energy. By varying the number of particles, DSVGD enables a flexible trade-off between per-iteration communication load and number of communication rounds. DSVGD is shown to compare favorably to benchmark frequentist and Bayesian federated learning strategies in terms of accuracy and scalability with respect to the number of agents, while also providing well-calibrated, and hence trustworthy, predictions. |
14,869 | Please write an abstract with title: Identifying Programming Skills Impacted in Students with Cognitive Disabilities, and key words: Education, Problem-solving, Programming profession, Faces. Abstract: This Full Research Paper aims to identify and compare the skills involved in learning programming and the difficulties that students with cognitive disabilities may face, discussing the impacts generated by these skills for these students. Several studies talk about what skills a person needs to learn to program. However, we do not have enough to consider the needs of students with disabilities, especially cognitive impairments. Did we conduct a study to answer the following research questions: RQ1 - What skills are involved in programming teaching? RQ2 -Can cognitive impairments affect the skills needed to program? We lift the part the skills involved in learning programming and the cognitive skills impediments in the literature. Finally, we made a critical analysis impact on that audience. By cross-referencing this information, we can highlight that the skills needed to program impact students with cognitive impairments such as math, logic, and problem-solving. This impact does not necessarily mean that these students cannot learn to program. We believe adapting materials, exercises and assessments can foster learning for this audience. |
14,870 | Please write an abstract with title: Low-Density Spreading Codes for NOMA Systems and a Gaussian Separability-Based Design, and key words: Maximum likelihood estimation, NOMA, Quadrature amplitude modulation, Message passing, Bit error rate, Parity check codes, Binary phase shift keying. Abstract: Improved low-density spreading (LDS) code designs based on the Gaussian separability criterion are conceived. We show that the bit error rate (BER) hinges not only on the minimum distance criterion, but also on the average Gaussian separability margin. If two code sets have the same minimum distance, the code set having the highest Gaussian separability margin will lead to a lower BER. Based on the latter criterion, we develop an iterative algorithm that converges to the best known solution having the lowest BER. Our improved LDS code set outperforms the existing LDS designs in terms of its BER performance both for binary phase-shift keying (BPSK) and for quadrature amplitude modulation (QAM) transmissions. Furthermore, we use an appallingly low-complexity minimum mean-square estimation (MMSE) and parallel interference cancellation (PIC) (MMSE-PIC) technique, which is shown to have comparable BER performance to the potentially excessive-complexity maximum-likelihood (ML) detector. This MMSE-PIC algorithm has a much lower computational complexity than the message passing algorithm (MPA).Code sets for MPA are designed similar to low-density parity-check (LDPC) codes to avoid cycles and to increase girth of the Tanner graph, code sets that are “optimal” for MMSE-PIC might not be optimal for MPA. |
14,871 | Please write an abstract with title: A Three Stage Ku-Band GaN HEMT Power Amplifier, and key words: Layout, Power amplifiers, Information processing, HEMTs, Market research, MODFETs, Power generation. Abstract: This paper describes the design of a Ku band power amplifier using GaN HEMTs. To obtain high efficiency, matching networks are incorporated into power amplifier. In order to design matching networks, the optimum source and load impedances are determined by the load pull analysis. As from single and two stage Ku band PAs do not provide the required gain for our requirement, a three stage Ku band PA is designed. At 13.63 GHz, the designed power amplifier provides more than 37.7dBm output power with large signal gain greater than 37dB and power added efficiency close to 40%. |
14,872 | Please write an abstract with title: Modelling of three-phase uniform symmetrical sampling digital PWM for power converter, and key words: Sampling methods, Pulse width modulation, Pulse width modulation converters, Mathematical model, Space vector pulse width modulation, Circuit simulation, Magnetic analysis, Magnetic circuits, AC generators, Mathematical analysis. Abstract: A mathematical approach of modelling and analysing three-phase pulse width modulation (PWM) is presented. The three-phase flyback converter required a unique pattern of PWM to optimise the power transfer in the magnetic circuit used in the converter. The three-phase PWM is generated digitally based on uniform symmetrical sampling technique using Xilinx chip. The generated PWM pattern is able to reduce the low order of harmonic components present in the input AC supply. Although software simulation could simulate the PWM pattern, it does not represent the exact pattern as been generated digitally. The mathematical approach used is to model the PWM pattern exactly as been created digitally. The proposed mathematical technique could also be used to analyse any digital PWM. The result of the mathematical analysis on the PWM pattern could be used to study the characteristics of the pattern such as maximum and minimum value of duty cycle, pulse width, turn-on time, turn-off time and modulation index. To verify the validity of the proposed technique, the results obtained from the mathematical model, experimental and simulation using PSpice were compared. |
14,873 | Please write an abstract with title: Directional Properties of Spatial Dipoles Arrays Located Above Perfectly Conducting Plane, and key words: Three-dimensional displays, Dipole antennas, Shape, Numerical analysis, Software algorithms, Interference, Directive antennas. Abstract: The fast active algorithms and software for numerical analysis of the radiation patterns and directive gains of 2D and 3D antenna arrays of the dipoles with axially separated amplitude-phase current distribution, located above a perfectly conducting (PEC) plane are developed. The analytical expressions obtained for the interference factors of the equidistant linear dipoles arrays located above a PEC plane along the axes of the Cartesian coordinate system (CCS) when the dipoles axes being parallel to CCS axes are used. Comparative numerical analysis of the directivity of antenna arrays of half-wave dipoles located at a distance of quarter wavelength above the screen depending on the distance between dipoles and their number is carried out. |
14,874 | Please write an abstract with title: "Pattern Length" Coding for Dithered Pictures, and key words: Facsimile, Code standards, Data engineering, Pattern matching, Predictive coding, Computer errors, Image sensors, Data communication, Communications Society, Maintenance engineering. Abstract: A new coding scheme for dithered halftone pictures, called `pattern length' coding, is proposed. This scheme is based on the fact that, in dithered pictures, some special horizontal bit-patterns frequently take place. Counting the pattern strings provides coding efficiency that is as good as any other scheme presented so far. In addition, this scheme is suitable for pictures which have both ordinary document areas and halftone areas, thus keeping better compatibility with standard facsimile coding schemes. |
14,875 | Please write an abstract with title: Enhancing Adaptive Event-Triggered Protocols for Multi-Agent Consensus with External Disturbances, and key words: Protocols, Eigenvalues and eigenfunctions, Laplace equations, Directed graphs, Symmetric matrices, Closed loop systems, Automation. Abstract: This paper studies the design of adaptive event-triggered protocols for consensus of linear multi-agent systems (MASs) with external disturbances. Different from most of the existing results that deal with undirected graphs, this paper addresses directed graphs, specifically graphs that are assumed to be strongly connected. Inspired by a recent development [1], this paper devises novel adaptive event-triggered protocols for linear MASs with all agents subject to external disturbances. Two specific designs of composite triggering conditions are analysed and discussed. Compared with the disturbance-free case, additional constraints need to be introduced to deal with external disturbances and moreover the time-dependent terms are allowed to take any finite functions, rather than a class of L1 functions. |
14,876 | Please write an abstract with title: The physics of high intensity dry magnetic separation, and key words: Physics, Magnetic separation, Superconducting magnets, Magnetic forces, Ores, Acceleration, Minerals, Particle separators, Electromagnets, Magnetic materials. Abstract: A stream of particles, falling under gravity and influenced by air drag, is analysed under the influence of a transverse magnetic force. The magnetic particles are deflected and collide with other particles. Under reasonable approximations concerning the nature of the particles and the type of collisions, an average transverse magnetic velocity is derived, as well as a maximum stream width for complete separation, which may be as much as 0.6cm. This is then combined with the calculated throughput to obtain an optimised value, which may be as large as 6 tons/hour for a magnet of diameter 365mm. |
14,877 | Please write an abstract with title: DHARMA: distributed home agent for robust mobile access, and key words: Robustness, Routing, DH-HEMTs, Circuits, Portable computers, Personal digital assistants, TCPIP, Internet, Delay, Space exploration. Abstract: Mobile wireless devices have intermittent connectivity, sometimes intentional. This is a problem for conventional Mobile IP, beyond its well-known routing inefficiencies and deployment issues. DHARMA selects a location-optimized instance from a distributed set of home agents to minimize routing overheads; set management and optimization are done using the PlanetLab overlay network. DHARMA's session support overcomes both transitions between home agent instances and intermittent connectivity. Cross-layer information sharing between the session layer and the overlay network are used to exploit multiple wireless links when available. The DHARMA prototype supports intermittently connected legacy TCP applications in a variety of scenarios and is largely portable across host operating systems. Experiments with DHARMA deployed on more than 200 PlanetLab nodes demonstrate routing performance consistently better than that for best-case Mobile IP. |
14,878 | Please write an abstract with title: Blockchain-Based Lightweight Authentication Protocol for IoT-Enabled Smart Agriculture, and key words: Smart agriculture, Productivity, Costs, Protocols, Authentication, Computer architecture, Robustness. Abstract: Blockchain technology has a significant application in smart farming due to its immutability, decentralization and transparency properties. Data exchanged in an Internet of Things (IoT)-based smart agriculture can be used to remotely monitor the fields and regulate the crop needs for optimal productivity. However, such data is sensitive to several attacks, such as man-in-the-middle attack, replay attack, ephemeral secret leakage attack, impersonation attack and denial of service (DoS) attack. The existing solutions to counter these attacks are either costly or lack significant security features. To mitigate these issues, we design a novel lightweight blockchain based authentication scheme based on a fully decentralized and distributed architecture. The designed scheme is subjected to a rigorous security analysis and also a formal security verification using the widely-used Automated Validation of Internet Security Protocols and Applications (AVISPA) tool, and it is shown that the scheme is robust and secure against various passive and active attacks. A detailed comparative analysis shows that the proposed scheme has the low communication cost and significantly lower computation cost while satisfying all the security and functionality features as compared to those for other existing relevant schemes. |
14,879 | Please write an abstract with title: Hybrid-Order Anomaly Detection on Attributed Networks, and key words: Anomaly detection, Deep learning, Decoding, Learning systems, Image edge detection, Informatics, Computer science. Abstract: Anomaly detection on attributed networks has received an increasing amount of attention in recent years. Despite the success, most of the existing methods only focus on detecting the abnormal nodes while fail to detect the abnormal subgraphs. In this paper, we define a new problem of hybrid-order anomaly detection on attributed networks, which aims to detect both of the abnormal nodes and subgraphs. To this end, a new deep learning model called Hybrid-Order Graph Attention Network (HO-GAT) is developed, which is able to simultaneously detect the abnormal nodes and motif instances in an attributed network. In order to model the mutual influence between nodes and motif instances, the learning procedures of the node representation and the motif instance representation are integrated into a unified graph attention network with a novel hybrid-order self-attention mechanism. After learning the node representation and the motif instance representation, two decoders are respectively designed to reconstruct the attribute information of the nodes and motif instances, and the hybrid-order topological structure among nodes and motif instances. And finally, the reconstruction errors are utilized as the abnormal score of nodes and motif instances respectively. Extensive experiments conducted on real-world datasets have confirmed the effectiveness of the HO-GAT method. |
14,880 | Please write an abstract with title: Failure analysis and virtual qualification of PBGA under multiple environmental loadings, and key words: Failure analysis, Qualifications, Electronics packaging, Plastic packaging, Assembly, Printed circuits, Aerospace testing, Circuit testing, Circuit simulation, Soldering. Abstract: To investigate the long term reliability of plastic ball grid array packages in aerospace applications, a design of experiments was conducted to address the assembly process, printed circuit board pad type, underfill, and multiple environmental loadings. This paper discusses the design of experiments and the test results, including the failure analysis. Virtual qualification was also performed to simulate the solder joint reliability under thermal cycling and vibration loadings. |
14,881 | Please write an abstract with title: A Statistical Approach Toward Channel Modeling With Application to Large-Scale Censored Data, and key words: Vehicle-to-everything, Estimation, Channel models, Receivers, Fading channels, Data models, Vehicular ad hoc networks. Abstract: Connected vehicle safety and efficiency applications rely on vehicular wireless networks for information sharing. To study the performance of these networks, and numerous protocols designed for them, it is essential to be able to model the channel behavior. However, due to the complexity of the vehicular environment, such modeling has to rely on data collected from large scale field tests. A majority of data collection campaigns with a large number of vehicles utilize vehicular on-board units (transceivers) to collect data in the form of received signal strength (RSS) values. Such datasets are limited in information since only the RSS values of correctly received packets are recorded, leading to datasets that can be considered as censored; especially where packet losses are high. Therefore, deriving channel models that accurately represent the channel behavior at distances with considerable loss of packets is a challenge. In this paper, we propose Bernoulli Mapping Estimation, a novel approach for the estimation of distributions from censored samples. Additionally, we provide a general method and formulation for modeling the communication channel in vehicular environments, considering receiver characteristics, imperfections, and data sparsity. The proposed methods were applied to datasets collected from highway and intersection environments; and the derived models are shown to be accurate representations of the datasets. It is also shown that even with only a small fraction of the RSS values, the framework is able to produce fading models that are similar in characteristics to field data. |
14,882 | Please write an abstract with title: Simulating lithium-ion batteries operation with MODAL recent development and some test cases, and key words: Batteries, Testing, Computer aided software engineering, Electrodes, Charge transfer, Material storage, Power system modeling, Computational geometry, Chemicals, Computer interfaces. Abstract: In order to improve lithium-ion batteries design, an in-depth understanding of limiting phenomena is necessary. The experimental approach (test the battery as a black-box) can now be complemented by a practical computational alternative. Simulation not only can give reliable and useful information about the origin of low capacity or poor performance, but also insight about the way to improve the design or the operation of a battery. MODAL is a code solving a coupled mass and charge transfer problem, with specialized battery-oriented dialog boxes; the battery designer can input easily critical parameters (geometry, material, transport and chemical properties, charge profile...) and obtain computational results such as concentration profiles, interface current density or a conventional characteristic curve (potential vs. state of charge). This paper reviews some developments recently introduced in MODAL and gives examples of analysis allowing better understanding of battery operation. The test-cases presented show how some design options can hinder the best use of a battery and what can be done to improve the design of a cell, or choose ad-hoc operation to get optimal use of an existing cell. Among the test-cases, the roles of the substrate interfacial area and of the charge procedure are explored in detail. Results are presented as classical (characteristic) curves and we discuss how the internal concentration profile can be used for a practical improvement of the cell (i.e. improve discharge rate via an increase of lithium salt concentration). |
14,883 | Please write an abstract with title: SMART BEAR: A large scale pilot supporting the independent living of the seniors in a smart environment, and key words: Monitoring, Biomedical monitoring, Diseases, Senior citizens, Auditory system, Temperature sensors. Abstract: SMART BEAR is a multinational European research project implementing an innovative, secure and privacy-preserving platform with market available wearable and medical devices, along with smart home sensors. The solution will target the elderly population who suffer from Hearing Loss, Cardio Vascular Diseases, Cognitive Impairments, Mental Health Issues and Balance Disorders. The platform will be tested and validated in five large scale pilots, in six different countries and 5100 individuals, providing evidenced-based interventions on lifestyle, medical significant risk factors, and chronic disease management. The present work demonstrates the initial requirements collection and analysis, along with the architecture and the Decision Support System, which will provide the evidence on the recommendations to the individuals. |
14,884 | Please write an abstract with title: A Cascade Fractional Controller for Hybrid Power System with Hybrid Energy Storage, and key words: Magnetomechanical effects, Redox, Hybrid power systems, Wind turbines, Batteries, Compounds, Superconducting magnetic energy storage. Abstract: The Load Frequency Control (LFC) of compound power system is investigated in this paper under deregulation condition. The proposed system is divided into two areas. Area-l includes a thermal system, a biogas plant, Electric Vehicle (EV) and Dish Stirling Solar Thermal (DSTS) and Area-2 includes a thermal system, a biogas plant, EV and Wind Turbine System (WTS). The whole power generated by DSTS and WTS is fed to respective area. A modified crossbreed two degree freedom controller is considered. To improve controller gain, the Quasi Opposition Lion Optimization Algorithm (QOLOA) is applied. To damp oscillation in response of test system Hybrid Energy Storage (HES) is applied. HES consist of Redox Flow Battery (RBF) and Super Magnetic Energy Storage (SMES). |
14,885 | Please write an abstract with title: Effect of impedance loading at higher harmonics on passive intermodulation in antennas, and key words: Impedance, Loaded antennas, Antenna measurements, Connectors, Microstrip antennas, Dielectric loss measurement, Prototypes, Testing, Diodes, Assembly. Abstract: The goal of this work was to find out how the reflected PIM products are affected by different loading conditions at the 2nd and 3rd harmonics of excitation. The assembly, consisting of a GSM900 antenna and a microstrip feeding line with different impedance loads provided at 2nd and 3rd harmonics, was prototyped and measured with respect to PIM performance. As the PIM source, an SMA connector was used at the input of the antenna. Such a connector is very typical in patch antenna feeds and appears to be problematic in PIM sense. |
14,886 | Please write an abstract with title: BERTina: A BERT-powered HIV/AIDS Question Answering Tool, and key words: Pandemics, Bit error rate, Machine learning, Natural language processing, Robustness, Information and communication technology, Viruses (medical). Abstract: The HIV/AIDS (Human Immunodeficiency Virus/Acquired Immuno-Deficiency Syndrome) pandemic is still prominent in the global South. However, the proper messaging concerning this pandemic is still a challenge; especially in resource-limited countries. Fortunately, the use of Information and Communication Technology (ICT) can assist in resolving this problem. In this paper, we propose a Natural Language Processing (NLP) tool called BERTina, which can be used as an HIV/AIDS question answering tool. The utility of the BERTina tool is underlined by the robustness of this tool against adversarial questions. |
14,887 | Please write an abstract with title: MIMO capacity with interference, and key words: MIMO, Channel state information, Transmitters, Interchannel interference, Receiving antennas, Transmitting antennas, Covariance matrix, Rayleigh channels, Fading, Antenna arrays. Abstract: System capacity is considered for a group of interfering users employing single-user detection and multiple transmit and receive antennas for flat Rayleigh-fading channels with independent fading coefficients for each path. The focus is on the case where there is no channel state information at the transmitter, but channel state information is assumed at the receiver. It is shown that the optimum signaling is sometimes different from cases where the users do not interfere with each other. In particular, the optimum signaling will sometimes put all power into a single transmitting antenna, rather than divide power equally between independent streams from the different antennas. If the interference is either sufficiently weak or sufficiently strong, we show that either the optimum interference-free approach, which puts equal power into each antenna, or the approach that puts all power into a single antenna is optimum and we show how to find the regions where each approach is best. |
14,888 | Please write an abstract with title: Baryonic clues to the puzzling diversity of dwarf galaxy rotation curves, and key words: galaxies: dwarf, galaxies: evolution, galaxies: formation, galaxies: haloes, dark matter, cosmology: theory. Abstract: We use a compilation of disc galaxy rotation curves to assess the role of the luminous component (‘baryons') in the rotation curve diversity problem. As in earlier work, we find that rotation curve shape correlates with baryonic surface density: high surface density galaxies have rapidly rising rotation curves consistent with cuspy cold dark matter haloes; slowly rising rotation curves (characteristic of galaxies with inner mass deficits or ‘cores') occur only in low surface density galaxies. The correlation, however, seems too weak to be the main driver of the diversity. In addition, dwarf galaxies exhibit a clear trend, from ‘cuspy’ systems where baryons are unimportant in the inner mass budget to ‘cored’ galaxies where baryons actually dominate. This trend constrains the various scenarios proposed to explain the diversity, such as (i) baryonic inflows and outflows during galaxy formation; (ii) dark matter self-interactions; (iii) variations in the baryonic mass structure coupled to rotation velocities through the ‘mass discrepancy–acceleration relation’ (MDAR); or (iv) non-circular motions in gaseous discs. Together with analytical modelling and cosmological hydrodynamical simulations, our analysis shows that each of these scenarios has promising features, but none seems to fully account for the observed diversity. The MDAR, in particular, is inconsistent with the observed trend between rotation curve shape and baryonic importance; either the trend is caused by systematic errors in the data or the MDAR does not apply. The origin of the dwarf galaxy rotation curve diversity and its relation to the structure of cold dark matter haloes remains an open issue. |
14,889 | Please write an abstract with title: Power Management on A Fuzzy Base Small Scale Microgrid Based on Hybrid Wind and Solar Battery, and key words: Fuzzy logic, Renewable energy sources, Power system management, Microgrids, Control systems, Hybrid power systems, Power electronics. Abstract: A small-scale hybrid wind-solar-battery microgrid’s energy management system is proposed in this study. To verify the function of the proposed hybrid micro grid, control algorithms, power electronic converters and controllers are designed, as well as needed control algorithms, power electronic converters and controllers. This tiny grid is self-contained and serves as a trial ground for various energy management system and control algorithm. An energy management system is developed based on fuzzy logic technique. |
14,890 | Please write an abstract with title: Predicting miRNA-Disease Association Based on Improved Graph Regression, and key words: Diseases, Semantics, Predictive models, Prediction algorithms, Matrix decomposition, Biological system modeling, Proteins. Abstract: Recently, as a growing number of associations between microRNAs (miRNAs) and diseases are discovered, researchers gradually realize that miRNAs are closely related to several complicated biological processes and human diseases. Hence, it is especially important to construct availably models to infer associations between miRNAs and diseases. In this study, we presented Improved Graph Regression for miRNA-Disease Association Prediction (IGRMDA) to observe potential relationship between miRNAs and diseases. In order to reduce the inherent noise existing in the acquired biological datasets, we utilized matrix decomposition algorithm to process miRNA functional similarity and disease semantic similarity and then combining them with existing similarity information to obtain final miRNA similarity data and disease similarity data. Then, we applied miRNA-disease association data, miRNA similarity data and disease similarity data to form corresponding latent spaces. Furthermore, we performed improved graph regression algorithm in latent spaces, which included miRNA-disease association space, miRNA similarity space and disease similarity space. Non-negative matrix factorization and partial least squares were used in the graph regression process to obtain important related attributes. The cross validation experiments and case studies were also implemented to prove the effectiveness of IGRMDA, which showed that IGRMDA could predict potential associations between miRNAs and diseases. |
14,891 | Please write an abstract with title: Robust emulations of shared memory in a crash-recovery model, and key words: Robustness, Emulation, Computer crashes, Message passing, Read-write memory, Workstations, Laboratories, Hardware, Distributed algorithms, Fault tolerance. Abstract: A shared memory abstraction can be robustly emulated over an asynchronous message passing system where any process can fail by crashing and possibly recover (crash-recovery model), by having (a) the processes exchange messages to synchronize their read and write operations and (b) log key information on their local stable storage. This paper extends the existing atomicity consistency criterion defined for multiwriter/multireader shared memory in a crash-stop model, by providing two new criteria for the crash-recovery model. We introduce lower bounds on the log-complexity for each of the two corresponding types of robust shared memory emulations. We demonstrate that our lower bounds are tight by providing algorithms that match them. Besides being optimal, these algorithms have the same message and time complexity as their most efficient counterpart we know of in the crash-stop model. |
14,892 | Please write an abstract with title: Stock Price Prediction Based on Temporal Fusion Transformer, and key words: Deep learning, Support vector machines, Neural networks, Predictive models, Transformers, Thin film transistors, Numerical models. Abstract: Stock price prediction has been an important financial problem which receives increasing attention in the past decades. Existing literature focusing on stock markets forecasting considers the high volatility of stock prices caused by multiple factors. During past years, a number of deep neural networks have been gaining much attention, achieving more accurate results compared to the traditional linear and non-linear approaches. However, most of these neural networks only take time-series features into consideration, ignoring static metadata potentially affecting stock markets. This paper utilizes the state-of-art Temporal Fusion Transformer (TFT) for stock price prediction compared with Support Vector Regression (SVR) and Long Short-Term Memory (LSTM). The comparison for each model is evaluated based on two metrics: Mean Square Error (MSE) and Symmetric Mean Absolute Percentage Error (SMAPE). The results document that TFT achieves the lowest errors. |
14,893 | Please write an abstract with title: Domain strategy and coverage metric for validation, and key words: Hardware design languages, Design engineering, Integrated circuit synthesis, Circuit testing, Circuit faults, Emulation, Acceleration, Formal verification, Application specific integrated circuits, Systems engineering and theory. Abstract: An innovative domain strategy and coverage metric for integrated circuit design validation is proposed. The domain strategy generates test points to examine the borders of a domain to detect whether a design fault has occurred, as either one or more of these borders have shifted or else the corresponding predicate relational operator has changed. The domain coverage metric is applied to measure the completeness and quality of the validation approach. The domain strategy and coverage metric have been implemented using VPI (Verilog procedural interface) and have been applied to validation of industry circuits under design. Our domain coverage tool works smoothly with simulator and vector generator. The results showed that the domain strategy is efficient in generating test points, and the domain coverage metric is powerful in finding potential boundary faults. |
14,894 | Please write an abstract with title: Cybersecurity Empirics: Evaluating Machine Learning Techniques for Phishing Detection, and key words: cybersecurity, social media, phishing, NLP. Abstract: TIn an age dominated by internet usage, the threat of phishing attacks continues to plague users and organizations alike. Traditional cybersecurity mechanisms often fail to cope with the evolving tactics of cybercriminals, leading to a growing interest in machine learning-based solutions. This research evaluates the performance of four different machine learning classifiers-K-Nearest Neighbors (KNN), Naïve Bayes (NB), Decision Tree, and Artificial Neural Network (ANN)-in identifying phishing activities. A Python code framework is utilized for this evaluation, employing stratified k-fold cross-validation for reliable results. Multiple performance metrics indicate that machine learning provides an adaptable and effective tool against phishing. This research serves as a stepping stone for future development in this crucial area, urging continuous advancements to stay ahead of ever-evolving cybersecurity threats. |
14,895 | Please write an abstract with title: Product Recommendation and Context Validation Based E-Commerce System With Currency Free Economy, and key words: Visualization, Machine learning algorithms, Linear regression, Market research, Natural language processing, Monopoly, Electronic commerce. Abstract: Due to the covid-9 situation, online shopping shows rapid growth among Sri Lanka and other countries. Meanwhile, with the visible downward trend of the Sri Lankan economy, people have been suffering due to inflation, leading to higher expenses of goods and services. A web-based solution called ‘Ceylon Barter Bay’ was developed as an e-bartering platform for Sri Lankans to get bartering experience and develop one-to-one trading. This paper comes with an appropriate business model for ‘Ceylon Barter Bay’ as a novice entrepreneur idea. This website was developed with enhanced abuse detectors and a related product recommendation system. Natural language processing and machine learning techniques are used in the process to get a better solution. Since the developed system is mainly based on advertising, a random forest algorithm-based machine learning model with 99% accuracy detects the context offensiveness. To detect violent behavior in feedback/comments, the logistic regression algorithm-based machine learning model was used with 88% accuracy. ‘Ceylon Barter Bay’ will recommend related items. Both collaborative and content-based recommendations have been performed using linear regression, respectively. In Sri Lanka, this has been recognized as an acceptable solution to break the monopoly of money via a web-based application |
14,896 | Please write an abstract with title: Optimal-Horizon Model Predictive Control with Differential Dynamic Programming, and key words: Heuristic algorithms, Stochastic processes, Reinforcement learning, Prediction algorithms, Real-time systems, Dynamic programming, Robots. Abstract: We present an algorithm, based on the Differential Dynamic Programming framework, to handle trajectory optimization problems in which the horizon is determined online rather than fixed a priori. This algorithm exhibits exact one-step convergence for linear, quadratic, time-invariant problems and is fast enough for real-time nonlinear model-predictive control. We show derivations for the nonlinear algorithm in the discrete-time case, and apply this algorithm to a variety of nonlinear problems. Finally, we show the efficacy of the optimal-horizon model-predictive control scheme compared to a standard MPC controller, on an obstacle-avoidance problem with planar robots. |
14,897 | Please write an abstract with title: Junction engineering and modeling for advanced CMOS technologies, and key words: CMOS technology, Semiconductor device modeling, Boron, Annealing, Temperature, Implants, Amorphous materials, MOS devices, Calibration, Semiconductor process modeling. Abstract: This paper discusses an integrated modeling approach for diffusion profiles in advanced CMOS technologies. First, for USJ (Ultra-Shallow Junction) arsenic modeling, in addition to a fully-coupled model with implant damage, amorphous layer formation which depends on the Frenkel pair concentration and evolution of (311) defects and dislocation loops based on EOR (End of Range) defects are also used. Secondly, in order to improve polysilicon activation, a hybrid (arsenic + phosphorus) Source/Drain is used for NMOS. We also address the calibration of the hybrid Source/Drain for with various anneal temperatures. It is shown that modeling of the hybrid Source/Drain profile can be achieved by optimization of the dopant's Fermi level dependent diffusivity and the initial value of the point defect concentration in the equilibrium state. Finally, uphill diffusion at low anneal temperature is observed for BF2 USJ and is enhanced with Ge pre-implants. It is caused by a steep interstitial gradient created by preamorphisation and EOR damage, ultra-shallow boron profile, and boron long-hop diffusion. A BIC (Boron-Interstitial Cluster) model is employed to model boron diffusion after a spike RTA at both extension and S/D regions. |
14,898 | Please write an abstract with title: The changing role of tutors: forming a community of practice in a distributed learning environment, and key words: Context, Communications technology. Abstract: An evaluation of a distributed learning environment (DLE) of a regional NSW university provided the context to examine the changing role of tutors in new learning environments. It examines how the tutors started to form a community of practice in the first year of operation. The distance from the main campus made communication difficult for the tutors, lecturers and students and the use of information and communication technologies (ICT), at times, added to the challenge. This paper identifies ways that the tutor role changes in a DLE and how the development of a community of practice can support this change. |
14,899 | Please write an abstract with title: Fast Computation of Robot-Obstacle Interactions in Nonholonomic Trajectory Deformation, and key words: Mobile robots, Orbital robotics, Closed-form solution, Trajectory, Filtering, Filters, Spatial coherence, Kinematics, Navigation, Motion detection. Abstract: This paper deals with the optimization of Robot-Obstacle interaction computations, in the context of non-holonomic trajectory deformation for mobile robots. We first recall the principle of the trajectory deformation and the role of the potential field gradient in the configuration space. The contribution of the paper is twofold. First we show that the potential field gradient can be computed without any closed-form expression of the potential function if this latter depends only on the distance between the robot and the obstacles. Then an algorithm to filter obstacles that have no influence in Robot-Obstacle interactions is presented. This algorithm takes advantage of the spatial coherence of the planned trajectory, and has been evaluated by experiments on mobile robot Hilare2 towing a trailer. |
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