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17,000 | Please write an abstract with title: Functional infrared imaging in the diagnosis of the myofascial pain, and key words: Infrared imaging, Pain, Temperature, Dentistry, Testing, Thermal stresses, Head, Neck, Performance evaluation, Cameras. Abstract: Functional infrared imaging has been used to study 17 patients, affected by myofascial pain, and 19 healthy subjects during maximal voluntary clenching (MCV). Aim of the study was to attempt to discriminate patients from healthy subjects through the analysis of the skin temperature distribution and its change during the clenching. The prestress and the post-stress temperatures were evaluated bilaterally for several regions of interest. We calculated differences in temperature between sides (/spl Delta/Ts) at each time (pre and post), and between times (/spl Delta/Tt) for each side (left and right). Subsequently, we compared /spl Delta/Ts and /spl Delta/Tt between the healthy and myofascial pain groups. /spl Delta/Ts was significantly higher in sufferers compared to healthy people (p<0.05) for both types of evaluation (by side and by time). /spl Delta/Ts was significantly different for masseter and sternocleidomastoid, whereas /spl Delta/Tt was higher in almost all sites (masseter, sternocleidomastoid, cervical and upper trapezius). Healthy subjects, undergoing MVC, showed the lowest /spl Delta/T value variability, suggesting that temperature remained constant despite the induced physical exercise. Functional infrared imaging seems to distinguish healthy subjects from the patients suffering myofascial pain in almost all the investigated sites. |
17,001 | Please write an abstract with title: Generative Plug and Play: Posterior Sampling for Inverse Problems, and key words: Plug-and-Play (PnP), Inverse problems, Generative model, Posterior sampling. Abstract: Over the past decade, Plug-and-Play (PnP) [1], [2] has become a popular method for reconstructing images using a modular framework consisting of a forward and prior model. The great strength of PnP is that an image denoiser can be used as a prior model while the forward model can be implemented using more traditional physics-based approaches. However, a limitation of PnP is that it reconstructs only a single deterministic image.In this paper, we introduce Generative Plug-and-Play (GPnP), a generalization of PnP to sample from the posterior distribution. As with PnP, GPnP has a modular framework using a physics-based forward model and an image denoising prior model. However, in GPnP these models are extended to become proximal generators, which sample from associated distributions. GPnP applies these proximal generators in alternation to produce samples from the posterior. We present experimental simulations using the well-known BM3D denoiser [3]. Our results demonstrate that the GPnP method is robust, easy to implement, and produces intuitively reasonable samples from the posterior for sparse interpolation and tomographic reconstruction. Code to accompany this paper is available at https://github.com/gbuzzard/generative-pnp-allerton. |
17,002 | Please write an abstract with title: Timing Errors in STA-based Gate-Level Simulation, and key words: Integrated circuit modeling, Delays, Engines, SPICE, Tools, Computational modeling. Abstract: In this paper, we demonstrate that conventional STA-based, functional, gate-level simulation of asynchronous circuits with cycles is only as accurate as the STA engine used. This is, firstly because cycle cuts create local slew errors at cutpoints, and secondly because slew propagation may not be upper-bounded across multiple cut points in the same cycle. The use of an ASTA engine, which does not cut cycles, and properly bounds slews across cycles is a possible solution, which can indeed serve as an upper bound over SPICE, transistor level similations. We contrast STA and ASTA-based SDF-annotated gate-level simulation results, with transistor level SPICE results, and demonstrate the impact of timing errors. |
17,003 | Please write an abstract with title: A case for network-centric buffer cache organization, and key words: Computer aided software engineering, Network servers, Linux, Optical fiber devices, File systems, File servers, Computer science, Computer architecture, Data communication, Measurement. Abstract: The emergence of clustered and networked storage architecture gives rise to a new type of server which acts as a data conduit over the network for remotely stored data. These servers, which we call pass-through servers, are mainly responsible for passing the data through them without interpreting it in any way. In this paper, we put forward a scheme of network-centric buffer cache management. This scheme can facilitate the data transmission through pass-through servers by avoiding redundant data copying, and by caching the data in a network-ready form, while having no modifications to the existing buffer cache organization. The performance measurement on an NFS server, using iSCSI storage, running on Linux, with this scheme shows throughput improvement of more than 50% compared to an NFS server on common Linux, while consuming about 40% less CPU resource. |
17,004 | Please write an abstract with title: A large signal model of GaAs MESFET, and key words: Gallium arsenide, Transconductance, MESFET circuits, Intrusion detection, Frequency, Microwave transistors, Equivalent circuits, Voltage, FETs, HEMTs. Abstract: Presented in this paper is the way of getting large signal parameters of MESFET model by the use of small signal S-parameters. Small-signal S-parameters allow expressing to nonlinearity of model, which are used in account of large-signal MESFET model. |
17,005 | Please write an abstract with title: MixTConv: Mixed Temporal Convolutional Kernels for Efficient Action Recognition, and key words: Convolution, Computational modeling, Benchmark testing, Network architecture, Feature extraction, Spatiotemporal phenomena, Pattern recognition. Abstract: To efficiently extract spatiotemporal features of video for action recognition, most state-of-the-art methods integrate 1D temporal convolutional filters into 2D CNN backbones. However, they all exploit 1D temporal convolutional filters of fixed kernel size (i.e., 3) in their network building block, thus have suboptimal temporal modeling capability to handle both long-term and short-term actions. To address this problem, we first investigate the impacts of different kernel sizes for the 1D temporal convolutional filters. Then, we propose a simple yet efficient operation called Mixed Temporal Convolution (MixTConv), which consists of multiple depthwise 1D convolutional filters with different kernel sizes. By plugging MixTConv into the conventional 2D CNN backbone ResNet-50, we further propose an efficient and effective network architecture named MSTNet for action recognition, and achieve state-of-the-art results on multiple large-scale benchmarks. |
17,006 | Please write an abstract with title: A Study on the First Return Stroke in a Thunderstorm Cell, and key words: Reflectivity, Clouds, Lightning protection, Radar, Arrays, Antenna arrays. Abstract: We have classified the first return stroke (RSlst) in a thunderstorm cell using the data recorded by a low-frequency mapping system called Fast Antenna Lightning Mapping Array (FALMA). It is found that the cloud-to-ground (CG) flashes in the cell can be apparently grouped into typical CG, hybrid CG, and CG without apparent PB processes. The majority (61/82) of RSlst are located in the area with the combined reflectivity larger than 30 dBZ. The RS1st in typical CG and in hybrid CG have nearly the same average intensities (5,900 versus. 5,700 DU), both are surprisingly smaller than that for the RS1st without PB processes (7,990 DU). The other properties, involving lightning initiation height, radar echo features, and the horizontal distance between the lightning initiation and RS1st, also have obvious differences among three types of CG flashes. In order to give explanations for such differences, we suggest that it should be deserved to further study the thunderstorm structure and charge regions in the future. |
17,007 | Please write an abstract with title: Volume Bragg Grating Fabrication by Femtosecond Laser Pulses, and key words: Fabrication, Bragg gratings, Silicon compounds, Media, Solid lasers, Laser beams, Ultrafast optics. Abstract: We report on the fabrication of volume Bragg gratings (VBGs) in the bulk of fused silica glass sample. Various VBGs fabrication approaches including Gaussian laser beam approach and Gaussian-Bessel approach considered. |
17,008 | Please write an abstract with title: Symbol mapping diversity design for packet retransmissions through fading channels, and key words: Fading, Diversity reception, Automatic repeat request, Bit error rate, Phase shift keying, Quadrature amplitude modulation, Upper bound, Throughput, Error correction, Transmitters. Abstract: We present a simple, but effective, method of enhancing and exploiting diversity from multiple packet transmissions in systems that employ nonbinary linear modulations such as PSK and QAM. This diversity improvement results from redesigning the symbol mapping for each packet transmission. Using a general framework for evaluating the upper bound of bit error rate (BER) with multiple transmissions, a criterion to obtain optimal symbol mappings is attained. The optimal adaptation scheme reduces to solving the well known quadratic assignment problem (QAP). Symbol mapping adaptation only requires a small increase in receiver complexity but provides very substantial BER gains when applied to flat-fading channels. |
17,009 | Please write an abstract with title: Web server attack categorization based on root causes and their locations, and key words: Web server, Intrusion detection, Web services, Protection, Information security, Access control, Computer crashes, Computer science, Frequency conversion, Service oriented architecture. Abstract: Frequency of attacks on Web services and resulting damage continue to grow as Web services become popular. Unfortunately, existing signature-based intrusion detection techniques are inadequate in providing reasonable degree of Web security. Web attacks are diverse in nature, and typical Web architecture consists of complex and hierarchically organized components. Because attack strategies often vary depending on the Web contents, it is impossible to develop fixed patterns capturing unknown attacks. Protection mechanisms such as anomaly-based intrusion detection and application-level IDS, tailored to Web services, are needed to detect Web attacks. The first step in developing Web application IDS is to analyze and categorize possible Web attacks and vulnerabilities. In this paper, we classify Web attacks by analyzing the root causes and the locations where they occur. This research is useful in developing Web IDS modules, tracking emerging trends on Web attacks, and testing Web applications against potential vulnerabilities. |
17,010 | Please write an abstract with title: A separative high-order framework for monotonic convergent iterative learning controller design, and key words: Convergence, Control systems, Design engineering, Intelligent systems, Educational institutions, Uncertainty, Design methodology, Feedback, Actuators, Frequency domain analysis. Abstract: This paper proposes a separative high-order framework, both in the iteration axis and in the time axis, for monotonic convergent iterative learning controller (ILC) design. When there exist uncertainties which may variant from iteration to iteration, i.e. iteration-dependent, the existing ILC design methods cannot be used to achieve monotonic convergence with small error. In this situation, an ILc updating law of high-order in both time-axis and iteration-axis is necessary. It is found that the high-order in time-axis is to condition the system dynamics so that a monotonic convergence can be achieved and the high-order in iteration-axis is to reject the iteration-dependent disturbance by virtue of the internal model principle (IMP). As illustrated in this paper, these two high-order schemes can be designed separately. A detailed design example is presented to illustrate the new design framework proposed in this paper. |
17,011 | Please write an abstract with title: A new method of on-line grid impedance estimation for PV inverter, and key words: Inverters, Impedance measurement, Photovoltaic systems, Solar power generation, Power quality, Monitoring, Hardware, Costs, Current measurement, Voltage measurement. Abstract: The recent increase in photovoltaic (PV) installations calls for new and better power quality requirements with respect to connection to the grid supply. Therefore, different methods are typically used for continuous grid monitoring, usually by using external devices. In this paper a new method for on-line measuring the grid impedance is presented. The presented method requires no extra hardware being accommodated by typical PV inverters, sensors and CPU, to provide a fast and low cost approach of on-line impedance measurement. By injecting a noncharacteristic harmonic current and measuring the voltage grid response it is possible to evaluate the grid impedance. Practical test on an existing PV inverter validate the new method. |
17,012 | Please write an abstract with title: Probabilistic Voltage Instability Assessment of Smart Grid Based on Cross Entropy Concept, and key words: Renewable energy sources, Voltage measurement, Probabilistic logic, Entropy, Smart grids, Security, Reliability. Abstract: Smart grids, which benefit from the deployment of new technologies such as renewable energy sources, electric vehicles, SCADA and PMU systems and etc., are becoming increasingly complex and uncertain, that can affect security and reliability of these systems. Power variation in generation units and loads demand causes variation in buses voltage that can reach to collapse point and cause instability in smart grids. Therefore instability assessment from buses voltage point of view under uncertain behaviors of smart grids is necessary and important for operation studies of these systems. In this paper by use of cross entropy concept, a new method for bus voltage instability assessment, in which stochastic and uncertain behavior of smart grids had been considered, is introduced. The distance between operational voltage and collapse point for each bus by use of Kullback Libeler divergence is evaluated to calculate instability of system voltage under uncertain operation of system. The IEEE 30-bus system has been analyzed by use of Monte Carlo simulation to evaluate the proposed method. |
17,013 | Please write an abstract with title: Convolutional Normalizing Flows for Deep Gaussian Processes, and key words: Training, Neural networks, Gaussian processes, Transforms, Semisupervised learning, Noise measurement, Approximation methods. Abstract: Deep Gaussian processes (DGPs), a hierarchical composition of GP models, have successfully boosted the expressive power of their single-layer counterpart. However, it is impossible to perform exact inference in DGPs, which has motivated the recent development of variational inference-based methods. Unfortunately, either these methods yield a biased posterior belief or it is difficult to evaluate their convergence. This paper introduces a new approach for specifying flexible, arbitrarily complex, and scalable approximate posterior distributions. The posterior distribution is constructed through a normalizing flow (NF) which transforms a simple initial probability into a more complex one through a sequence of invertible transformations. Moreover, a novel convolutional normalizing flow (CNF) is developed to improve the time efficiency and capture dependency between layers. Empirical evaluation shows that CNF DGP outperforms the state-of-the-art approximation methods for DGPs. |
17,014 | Please write an abstract with title: Characteristic Study of Solar Photovoltaic Array Under Different Partial Shading Conditions, and key words: Voltage, Mathematical models, Photovoltaic systems, Photovoltaic cells, Topology, Load modeling, Simulation. Abstract: Photovoltaic (PV) systems are frequently exposed to partial or complete shading phenomena. Partial shading has a profound impact on the performance of solar power generation. The operational performance of PV arrays under partial shading shows multiple maximum power point peaks, therefore it is challenging to identify the actual maximum power point. This paper investigates the impact of partial shading location on the output power of solar photovoltaic arrays with various configurations. Multiple photovoltaic strings, in both parallel and series configurations, are considered. Different random shading patterns are considered and analyzed to determine which configuration has higher maximum power point. The sensitivity of the partial shading can change according to the partial shading types, shading pattern, and the configuration used to connect all PV modules. Moreover, the study also investigates the output of the PV array with shading two random models, two consecutive models, and three random and consecutive modules. Experimental results validate the analysis and demonstrate the effect of various partial shading on the eficiency and performance of the PV system. |
17,015 | Please write an abstract with title: Partial Discharge Diagnosis Based on Variational Mode Decomposition and Multiscale Permutation Entropy, and key words: Partial discharges, Support vector machines, Empirical mode decomposition, Simulation, Switches, Feature extraction, Entropy. Abstract: Partial discharge diagnosis is considered as an important means to diagnose the insulation state of gas insulated switchgear (GIS). Aiming at the non-stationary characteristics of partial discharge (PD) signals, a feature extraction method based on variational mode decomposition (VMD) and multi-scale permutation entropy (MPE) is proposed. Firstly, VMD is used to decompose the PD signal, and multiple intrinsic modal functions are obtained; Then, the MPE of each modal component is calculated as the eigenvector. Finally, the MPE of modal component is input into SVM as feature vector for classification. Empirical mode decomposition (EEMD) and empirical mode decomposition (EMD) are compared to highlight the advantages of the proposed algorithm. The comparative simulation results demonstrate that, compared with the other two algorithms, this method can effectively extract the characteristic parameters, which provides a reference scheme for GIS PD diagnosis. |
17,016 | Please write an abstract with title: A method for extracting region of interest based on attractiveness and study for CE applications, and key words: Humans, Pixel, Home appliances, Focusing, Consumer electronics, Digital cameras, Content based retrieval, Watches, Image databases, Visual databases. Abstract: We propose a method to extract a region which includes the attention objects based on physical image features. Our method has a very simple structure, featuring edge magnitude and color contrast, and we can apply it for various consumer electronics (CE) applications. |
17,017 | Please write an abstract with title: Is Cross-Attention Preferable to Self-Attention for Multi-Modal Emotion Recognition?, and key words: Convolutional codes, Emotion recognition, Fuses, Convolution, Conferences, Aggregates, Speech recognition. Abstract: Humans express their emotions via facial expressions, voice intonation and word choices. To infer the nature of the underlying emotion, recognition models may use a single modality, such as vision, audio, and text, or a combination of modalities. Generally, models that fuse complementary information from multiple modalities outperform their uni-modal counterparts. However, a successful model that fuses modalities requires components that can effectively aggregate task-relevant information from each modality. As cross-modal attention is seen as an effective mechanism for multi-modal fusion, in this paper we quantify the gain that such a mechanism brings compared to the corresponding self-attention mechanism. To this end, we implement and compare a cross-attention and a self-attention model. In addition to attention, each model uses convolutional layers for local feature extraction and recurrent layers for global sequential modelling. We compare the models using different modality combinations for a 7-class emotion classification task using the IEMOCAP dataset. Experimental results indicate that albeit both models improve upon the state-of-the-art in terms of weighted and unweighted accuracy for tri- and bi-modal configurations, their performance is generally statistically comparable. The code to replicate the experiments is available at https://github.com/smartcameras/SelfCrossAttn |
17,018 | Please write an abstract with title: Electrical and optical localisation of leakage current and breakdown point in SiOC:H low-k dielectrics, and key words: Integrated optics, Electric breakdown, Moisture measurement, Optical variables measurement, Dielectrics, Microelectronics, Leakage currents. Abstract: This paper presents a novel methodology to observe the leakage current origin in SiOC:H low-$\kappa$ intermetallic dielectric as well as a method to localise electrically the breakdown point in usual comb/serpentine/comb structures. Our results indicate that high leakage current is a consequence of a global moisture-induced SiOC:H dielectric modification and demonstrate that EMMI observations of such leakage current is possible. Besides, we have disclosed and validated a fast electrical breakdown localisation method fully compatible with automated test steps such as Parametric Test to track eventual weaknesses in reliability structures for instance. |
17,019 | Please write an abstract with title: A hybrid supervised learning model for a medium-term MV/LV transformer loading forecast with an increasing capacity of PV panels, and key words: Photovoltaic systems, Load forecasting, Supervised learning, Machine learning, Predictive models, Load modeling. Abstract: The share of photovoltaic (PV) generation has increased quickly in the last decade. Many PV panels are connected behind-the-meter (BTM), so that they can not be identified with measurement equipment at MV/LV transformers. This poses a challenge for a medium-term MV/LV transformer loading forecast if the capacity of PV panels is increasing over time. Therefore, this paper proposes a hybrid approach for a medium-term load forecast (MTLF) of a MV/LV transformer with an increasing capacity of PV panels that are not separately measured. This approach combines a supervised learning model (data-driven approach) with a model to estimate the generation profile of the PV panels (model-based approach). The results indicate that the accuracy of the forecast improves significantly, while an accurate generation profile of the PV panels connected BTM or a disaggregation of the net load is unnecessary. |
17,020 | Please write an abstract with title: Language-based hand-printed character recognition: a novel method using spatial and temporal informative features, and key words: Character recognition, Natural languages, Hidden Markov models, Personal digital assistants, Neural networks, Variable speed drives, Digital signal processing, Formal languages, Artificial neural networks, Character generation. Abstract: We propose a new method for recognition - the domain-dependent bilingual hand-printed character recognition. We implemented two-stage recognition systems based on two important character properties, defined as spatial and temporal informative features. The proposed spatial informative features (SIF) are off-line characters' structures that are exploited in order to differentiate Thai from English characters. These features can also be called distinctive features (DF). In contrast, temporal informative features (TIF) are segments of characters extracted using our proposed features, called start-to-end point distance feature, and other standard on-line features. Our proposed TIF features help us to solve ambiguity occurred in several Thai and English character, which conventional features cannot resolve. In the recognition system, the first stage is performed the language classification task using distinctive features, while the second stage is using hidden Markov model (HMM) as the final classifier. The advantages of using language classification at the first recognition stage are two folds. First, the decision complexity at the final recognition stage can be reduced. Second, the observation stages of two independent language HMMs can be better optimized than one bilingual HMM. From the experimental results, language classification recognition accuracy is 99.31%, while the recognition accuracy of Thai and English characters are 91.67% and 90.23%, respectively. Hence, the overall recognition accuracy is 91.05%. |
17,021 | Please write an abstract with title: Evaluation of Instance-Based Learning and Q-Learning Algorithms in Dynamic Environments, and key words: Heuristic algorithms, Lakes, Games, Reinforcement learning, Task analysis, Unsupervised learning, Prediction algorithms. Abstract: Reinforcement learning is an unsupervised learning algorithm, where learning is based upon feedback from the environment. Prior research has proposed cognitive (e.g., Instance-based Learning or IBL) and statistical (Q-learning) reinforcement learning algorithms. However, an evaluation of these algorithms in a single dynamic environment has not been explored. In this paper, a comparison between the statistical Q-learning algorithm and the cognitive IBL algorithm is presented. A well-known environment, “Frozen Lake,” is used to train, generalize, and scale Q-learning and IBL algorithms. For generalizing, the Q-learning and IBL agents were trained on one version of the Frozen Lake and tested on a permuted version of the same environment. For scaling, the two algorithms were tested on a larger version of the Frozen Lake environment. Results revealed that the IBL algorithm used less training time and generalized better to different environment variants. The IBL algorithm was also able to show scalability by retaining its superior performance in the larger environment. These results indicate that the IBL algorithm could be proposed as an alternative to the standard reinforcement learning algorithms based on dynamic programming such as Q-learning. The inclusion of human factors (such as memory) in the IBL algorithm makes it suitable for robust learning in complex and dynamic environments. |
17,022 | Please write an abstract with title: Area Efficient Multi-Threshold Null Convenction Logic, and key words: Logic gates, Transistors, Power demand, CMOS technology, Design methodology, Digital circuits, MOS devices. Abstract: Multi-threshold null convention logic (MTNCL) is a commonly used asynchronous paradigm for designing low power NCL circuits. Traditionally, MTNCL circuits implemented using complementary metal oxide semiconductor (CMOS) technique that tends to occupy a large area. To address this limitation, a gate diffusion input (GDI) methodology is introduced for implementing MTNCL circuits. This GDI technique enables complex logic to be implemented using only two transistors that helps to reduce area utilization. In this paper, a novel approach to implement MTNCL designs based GDI methodology is proposed. The proposed approach has been verified by implementing TH23 MTNCL gate. Comparing to the conventional CMOS implementation, the proposed approach shows a 45% reduction in the area overhead. |
17,023 | Please write an abstract with title: Voiceai Systems to NIST Sre19 Evaluation: Robust Speaker Recognition on Conversational Telephone Speech, and key words: Training data, Speech recognition, NIST, Telephone sets, Acoustics, Speaker recognition, Data mining. Abstract: In this study, we present the VoiceAI (VAI) submissions to NIST SRE 2019 challenge on the task of speaker recognition using conversational telephone speech. Domain mismatching remains a challenging problem on SRE19. However, participants are unconstrained to use any public or proprietary data to mitigate this problem. Using larger scale and more diverse training data can effectively improve the performance of the front-end neural networks (NN). In our experiments, we focus on constructing robust systems using x-vectors. Different input acoustic features are also investigated. In addition, we propose hybrid neural architectures to utilizing the strength of different neural networks such as long short-term memory (LSTM), extended time delay neural network (ETDNN) and factorized TDNN (FTDNN). We also explore many back-end strategies to make full use of the development data and to relief the domain mismatching problem. Our best network topology, a FTDNN with two LSTMP layers, significantly outperforms the baseline on NIST SRE18 evaluation set (SRE18Eval). The final system, a fusion of five systems, yields EER 2.59%, minimum cost 0.153, and actual cost 0.155 on the progress data set, ranking second on the leaderboard among all participants. |
17,024 | Please write an abstract with title: Neighbor Discovery Algorithm in Wireless Ad Hoc Networks Based on Successive Interference Cancellation Technology, and key words: Silicon carbide, Signal to noise ratio, Transmitting antennas, Directive antennas, Directional antennas, Signal processing algorithms, Interference cancellation. Abstract: Wireless ad hoc network will have a broad application prospect in both military and civilian fields. It is the foundation of wireless ad hoc network to accurately and quickly complete neighbor discovery of all nodes. At present, most traditional neighbor discovery algorithms choose to discard packets when they collide, and ignore the impact of collision in theoretical analysis. This paper proposes a neighbor discovery algorithm based on successive interference cancellation technology, which introduces successive interference cancellation (SIC) technology to deal with the collision of data packets, and carries on the mathematical modeling and theoretical analysis of the algorithm. Finally, the performance of the algorithm is simulated. It is verified that the introduction of SIC technology will improve the performance of neighbor discovery algorithm. |
17,025 | Please write an abstract with title: Multichannel Many-Class Real-Time Neural Spike Sorting With Convolutional Neural Networks, and key words: Wireless communication, Feature extraction, Real-time systems, Hardware, Recording, System-on-chip, Convolutional neural networks. Abstract: Real-time in-sensor spike sorting is a forefront requirement in the development of brainmachine interfaces (BMIs). This work presents the characterization, design, and efficient implementation on a field-programmable gate array (FPGA) of a novel approach to neural spike sorting intended for implantable devices based on convolutional neural networks (CNNs). While the temporal features, the shape of the spike signals, could be highly mitigated from the ambient noise, the proposed classifier effectively extracts spatial features from the multi-channel neural signal to maintain high accuracy on the noisy data. The proposed classifier mechanism was tested on real data that is recorded from multi-channel electrodes, containing 27 neural units, and the classifier achieves 93.1% accuracy despite high temporal noise in the signal. For hardware synthesis, the CNN weights are quantized to reduce the model storage requirement by 93% compared to its floating point-precision version, and the model achieves an accuracy of 86.1%. |
17,026 | Please write an abstract with title: Compute Aided Diagnosis of Facial Paralysis Based on Pface, and key words: Muscles, Physics computing, Measurement standards, Cameras, Mouth, Computer science, Automatic testing, Psychology, Eye protection, Displacement measurement. Abstract: In this paper, a compute aided diagnosis approach is proposed to physicians in the diagnosis of single-sided facial paralysis. This approach is different from the existing nine subjective and hand-performed international scales such as House-Brackman. For voluntary expressions of a patient, this approach used Pface, which stems from Dface, to measure the asymmetry between two sides of the face. The experiments on test subjects revealed that Pface could differentiate the paralysis stats and normal stats and has the ability of automatic grading facial paralysis. Moreover, Pface of specific face areas can be used in supervision of the rehabilitation process. |
17,027 | Please write an abstract with title: Control of a dual stator winding induction machine as a source of dc power, and key words: Stator windings, Induction machines, Induction generators, Pulse width modulation, DC generators, Power generation, Rectifiers, Copper, Steady-state, Magnetic flux. Abstract: This paper investigates the use of a dual stator winding squirrel-cage induction machine for generating dc power using series or parallel connected ac-dc PWM rectifiers. The operating principles and constraints when generating under minimum total copper loss condition are explored using the machine steady-state model considering magnetizing flux saturation effects. Regulation of the dc voltage using concepts of the nonlinear input-output linearization method including the design of the controllers are set forth and confirmed to be effective by computer simulation results. Some experimental waveforms of the generator under load are also included in the paper. |
17,028 | Please write an abstract with title: Grinded Surface Roughness Prediction Using Data-Driven Models with Contact Force Information, and key words: Training, Analytical models, Mechatronics, Force, Predictive models, Surface roughness, Data models. Abstract: Surface roughness plays an important role in grinding; it can represent the grinding quality of machined parts. In previous research, analytical models and empirical models have been used to predict surface roughness. This research presented surface roughness prediction models based on linear regression and artificial neural networks of several types of model structures, then applied different features as model inputs, including force data directly get from the force sensor and those collected force data after statistical processing to reduce dimension. After conducting the prediction model, a self-developed grinding machine was used to collect the force data for model training and testing, and the mean absolute percentage error was used to evaluate the prediction performance. In the end, a neural network of three hidden layers was marked as the best model, which was useful for surface roughness prediction during grinding. |
17,029 | Please write an abstract with title: THz Wave Detection of Gap Defects Based on a Convolutional Neural Network Improved by a Residual Shrinkage Network, and key words: Air gaps, Atmospheric modeling, Wavelet transforms, Feature extraction, Imaging, Analytical models, Time-frequency analysis. Abstract: Internal air gap is a serious type of defect in the insulation equipment, which threatens the safe operation of the power grid. In order to diagnose the position and thickness of the internal air gap, this paper proposes a terahertz wave detection method based on wavelet analysis and a CNN (convolution neural network) model. According to the time-frequency characteristics of the wavelet cluster, the calculation method of air gap depth is proposed. To determine the thickness of the internal air gap, the performances of several classification methods, such as waveform feature analysis, Bayes, MLP (Multi-layer Perceptron), SVM (Support Vector Machine) and CNN are compared. The results show that the CNN modified by a residual shrinkage network and SVM (CNN-RSN-SVM) has the best performance. By adjusting the parameters, the classification accuracy of the CNN-RSN-SVM model can be elevated to 98.91%. Furthermore, the 3D imaging method of air gap defect based on wavelet analysis and CNN-RSN-SVM classification model is formed. |
17,030 | Please write an abstract with title: Development of Fluid Pump using 1-DOF Control Self-Bearing Motor for High-Speed Rotation in Liquid Nitrogen, and key words: Temperature sensors, Rotors, Temperature control, Magnetic sensors, Magnetic levitation, Liquid nitrogen, Sensor phenomena and characterization. Abstract: Zero-power control is proposed for temperature drift errors in eddy-current displacement sensors used in magnetic bearing and applied to a fluid pump using a self-bearing motor. In the experiments, the self-bearing motor was cooled from room temperature to liquid nitrogen temperature, and levitation and rotation experiments were carried out in liquid nitrogen without calibration of the sensor under low temperature. The experimental results show that the control current is small and unaffected by the temperature drift error of the displacement sensor, as well as the zero power control at room temperature. It was confirmed that the zero power control can reduce the effect of temperature drift of the eddy current displacement sensor used for the control. |
17,031 | Please write an abstract with title: Floating Memcapacitor Based on Knowm Memristor and Its Dynamic Behaviors, and key words: Memristors, Integrated circuit modeling, Voltage, Resistance, Equivalent circuits, Behavioral sciences, Phase change random access memory. Abstract: Previous studies about mem-element model focus on basic concept and equivalent circuit model of mem-elements while has little research based on commercial memristor. The object of this brief is to design and implement a voltage controlled floating memcapacitor based on Knowm memristor. On the one hand, a small number of off the shelf components of the memcapacitor model makes it easier for researchers to complete the experiment. On the other hand, nonlinear dynamical behaviors are investigated, such as power-off plot, dynamic route map (DRM) and DC V-Q plot. It is found that DRM of memcapacitor demonstrate different characteristics after considering current limiting resistor. Finally, PSPICE circuit model is designed and hardware experimental results are presented. |
17,032 | Please write an abstract with title: Current Situation and Countermeasures of Uncontrollable Infection of Severe Acute Pancreatitis, and key words: Schedules, Microorganisms, Hospitals, Ventilation, Indexes, Public healthcare, Strain. Abstract: Purpose: this thesis aims to explore the current situation and countermeasures of uncontrollable infection of severe acute pancreatitis. Method: 100 severe acute pancreatitis patients, who were admitted to an affiliated hospital of Kunming Medical University from September 2018 to November 2019, are selected into research, and infection factors and pathogenic bacteria distribution are observed during their corresponding treatment. Results: for severe acute pancreatitis patients, gender, age, and body mass index have little influence on their infection and P is larger than 0.05. Nevertheless, fasting time, diabetes, external pancreatic infection, multiple organ failure, APACHE II and mechanical ventilation exert a strong influence on their infection and P is less than 0.05. Moreover, 108 strains of pathogenic bacteria are detected in 100 patients, which fully proves multiple infections among patients. There are 74 strains of gram-negative bacteria, accounting for 68.51%, which is the highest proportion; 28 strains of gram-positive bacteria account for 25.93%; 6 fungi strains account for 5.56%, which is the least. Conclusion: the current situation of treating uncontrollable infection of severe acute pancreatitis in our country is not promising and patients are difficult to be fully cured due to constant consumption and repeatedly infection. Therefore, uncontrollable infection of severe acute pancreatitis may not be prevented and treated efficiently until prompt overall treatment, accurate intervention, and effective implementation of therapeutic schedule. |
17,033 | Please write an abstract with title: A comparative study of characterization techniques for oxide reliability in flash memories, and key words: Flash memory, Leakage current, Acceleration, Testing, Availability, Condition monitoring, Failure analysis, Statistical distributions, Oxidation, Microscopy. Abstract: We compare two different methods for extracting the leakage distribution from accelerated data-retention experiments. It is shown that the equivalent-cell (EC) scheme, which provides a fast estimation of leakage distribution in the array, is totally accurate as compared to a more detailed analysis of single memory cells within the array. The fair agreement between the results of the two characterization schemes is explained, and advantages of the EC technique for fast reliability monitoring in Flash memories are discussed. |
17,034 | Please write an abstract with title: Power Loss Model and Efficiency Analysis of a Boost Full-bridge Isolated Converter based on SiC MOSFETs for PV applications, and key words: Semiconductor device modeling, MOSFET, Analytical models, Silicon carbide, Switching frequency, Silicon, Load modeling. Abstract: This paper introduces the power loss model and efficiency analysis of the current-type active-clamped boost full-bridge isolated converter (BFBIC) used in the medium voltage photovoltaic DC boost system. SiC BFBIC is developed by using silicon carbide semiconductor devices. Silicon carbide has the advantages of high switching frequency and low loss, which can effectively reduce the volume of the converter and improve the overall efficiency. According to the ZVS modulation technology of BFBIC, the accurate loss model and calculation formula of SiC BFBIC are derived. Through simulation results and A 5kV/50kW experimental prototype, the power loss of each loss element at different loads at 50kHz switching frequency of full-bridge MOSFETs is analyzed, and the power loss distribution of each switching device under full load is also analyzed. The results show that the developed model can replicate the actual operating conditions of BFBIC and accurately calculate converter efficiency over a wide load range. The calculation results show that the theoretical efficiency of SiC BFBIC is 98.59%, which can significantly reduce the power loss and heating of the photovoltaic DC converter. |
17,035 | Please write an abstract with title: Deep Learning For Noisy Communication System, and key words: Training, Deep learning, Communication systems, Transmitters, Receivers, Collaborative work, Noise measurement. Abstract: In modern communication systems, channels vary with time due to the mobility of the transmitter (Tx) and the receiver (Rx). To achieve error-free communication in changing environments, Tx and Rx must effectively adapt to different noise levels. However, exiting frameworks face challenges during adaptation, leading to poor communication. In this paper, an independent pre-training collaborative learning framework is designed for tuning Tx and the Rx. The proposed framework incorporates more realistic challenges encountered in communication systems such as lack of feedback channels and the lack of updates at the Rx side. The experimental results show that the proposed approach can reduce noise up to 50% more than existing approaches and within a short training time. |
17,036 | Please write an abstract with title: A Comparative Study of Machine Learning for iOS based on Siam Betta Mobile Application, and key words: Training, Machine learning, Predictive models, Internet, Mobile applications, Animals, Urban areas. Abstract: Siam Betta, or Siamese fighting fish, is a popular fish in the a quarium trade. However, due to its variety, species classification is an obstacle f or many amateur aquatic animal breeders. Thus, to facilitate those amateurs on Thai Betta' species prediction, in this paper, some machine learning techniques have been applied, studied and deployed in an iOS application. Apple's Create ML framework and Microsoft's Custom Vision framework are investigated and used to build the machine learning model (mlmodel). The mlmodel is built from 6 species of Thai Betta images. In this paper, the performance of both frameworks in terms of the step of the training dataset, the accuracy parameters and the processing time by varying the number of images dataset from 350 to 1400 images have been compared. The results show that the Create ML framework predicted 100% correct at the number of images dataset equal and higher than 875 images but it takes the average processing time higher than that of the training model with Custom Vision around 2.1686 times at 50 images dataset in each class, and 4.4924 times at 200 images dataset in each class. |
17,037 | Please write an abstract with title: A Modified Vertex Method for Parallelization of Arbitrary Nested Loops, and key words: Processor scheduling, Parallel processing, Computer science, Upper bound. Abstract: A technique, permitting us to linearize constraints formed to find affine schedules for arbitrary nested loops, is presented. The main advantage of this technique is that it does not require finding the polytope vertices and results in the fewer number of inequalities and equalities than that yielded with the vertex technique. Affine schedules found are valid for the arbitrary positive lower and upper loop bounds. Experiments with the Livermore loops are discussed. The restriction of the technique and tasks for future research are discussed. |
17,038 | Please write an abstract with title: Finite-time robust observers for switched linear systems with state-dependent switching, and key words: Switched systems, Linear systems, Sufficient conditions, Uncertain systems, Fault detection, Switches, Observers. Abstract: The finite-time robust state observer design problem of switched linear systems in which both the external disturbance and the measurement noise are involved is studied here. Different from the existing literatures related to robust observers of switched systems, which consider arbitrary switching signals or dwell time switching signals, in this paper we consider state-dependent switching signals. We first propose the definition of finite-time interval observers for switched systems. Then, by giving the ranges of the external disturbance and the measurement noise, we construct finite-time interval observers for switched linear systems with state-dependent switching strategy. Next, by multiple Lyapunov functions method, some sufficient conditions characterizing the finite-time stability (FTS) of positive error systems under maximum constraints are derived and applied to solve the observer gains and the corresponding sliding motion issue is also discussed. Finally, an example on the state observers of switched systems is given for illustration. |
17,039 | Please write an abstract with title: Using Biped Robot on Knee Exoskeleton for Stair Climbing Assistance Analysis, and key words: Measurement units, Exoskeletons, Stairs, Angular velocity, Performance analysis, Servomotors, Robots. Abstract: Exoskeleton worn on human body becomes a complex biomechatronic system, and how to analyze it is a difficult research topic. In this study, a biped robot is developed for the knee exoskeleton analysis. The biped robot has four degrees of freedom, and fabricated with smart servo and inertial measurement units, which can provide motions information of the biped robot. In addition, the biped robot is dangled on a well-designed hanger to perform motions without considering the balance condition of the robot during the motions. Therefore, the exoskeleton assistance quality can be analyzed by comparing the difference of motion information while the robot performs actions with and without wearing the exoskeleton. In this research, the assistance performance analysis for the stair climbing motion of the knee exoskeleton is considered, and the position, the angular velocity and the current variation are discussed. Finally, the ability of the biped robot for analyzing the knee exoskeleton is verified. |
17,040 | Please write an abstract with title: Generalized refractive mixing dielectric model for moist soils, and key words: Dielectric constant, Soil measurements, Water, Dielectric measurements, Frequency, Remote sensing, Moisture measurement, Microwave bands, Spaceborne radar, Refractive index. Abstract: In this paper, a technique for estimating the maximum bound water content and complex dielectric constants for both the bound and the free water in soil is presented. The thus attained dielectric properties for the water in soil, are used to derive the Debye spectroscopic parameters for both types of water. Empirical data sets for the soil complex dielectric constant as a function of moisture measured only at two frequencies are sufficient for applying this technique. As a result the model for predicting soil complex dielectric constant in the microwave band is proposed and validated. |
17,041 | Please write an abstract with title: Degradation Mechanisms of Epoxy Molding Compound Subjected to High Temperature Long Term Aging, and key words: Degradation, Temperature distribution, Thermomechanical processes, Glass, Materials reliability, Aging, Compounds. Abstract: FCBGAs are finding applications in automotive underhood environments where they may be subjected to sustained temperatures of 125-200°C for sustained periods during operation. While, FCGBAs have been previously used in consumer applications where operating temperatures typically range in 55-85°C, relatively little is known on methods to design damage-tolerant packages in automotive underhood environments. There is insufficient information on plastic-encapsulated FCBGAs capable of surviving high temperatures for long periods (>100,000 hours). In this paper, the degradation mechanisms of epoxy-molding compound under sustained high temperature aging have been studied. Two popular molding compounds, EMC-1 and EMC-2 are studied under three aging temperatures of 100°C, below glass transition temperature, 125°C, around glass transition temperature and 150°C, above glass transition temperature. Thermo-gravimetric analysis has been conducted to study the weight loss change as the function of aging temperature and aging time. Differential scanning calorimetry has been conducted to study the curing behavior. The evolution of the storage modulus, loss modulus and the tangent-delta has been quantified for aging short-term aging up to 40-days and long-term aging up to 1-year at temperatures of 100°C and 150°C. |
17,042 | Please write an abstract with title: Single observer bearings-only tracking with the unscented Kalman filter, and key words: Target tracking, Motion analysis, Motion estimation, Trajectory, Motion measurement, Noise measurement, Position measurement, Velocity measurement, Goniometers, Working environment noise. Abstract: The basic problem in target motion analysis (TMA) is to estimate the trajectory of an object from noise corrupted measurement data. The position and velocity of an emitter source can be determined from the bearing angle measurements of a passive observer. The paper introduces the recently developed unscented Kalman filter (UKF) in application to bearings-only tracking. What is more, the UKF is compared to the traditional extended Kalman filter (EKF). Simulation shows that the method performs very well even under the adverse circumstances of a noisy environment. |
17,043 | Please write an abstract with title: Reverse Leakage Current Instability of Power Fast Switching Diodes Operating at High Junction Temperature, and key words: Leakage current, Diodes, Thyristors, Electric variables, Power electronics, Temperature control, Voltage control, Research and development, Silicon carbide, Silicon devices. Abstract: Some power electronics applications reveal performance weakness of fast recovery silicon diodes, in spite of significant advance made in their switching performance. The maximum operation junction temperature, specified in the data sheets is usually limited to 150 degC. Typical I-V reverse characteristics from room to high temperature, taken from commercial fast recovery diodes, available at this time are presented. Instability of the electrical characteristic is exhibited above 125 degC. A comparison between fast recovery and similar standard recovery diodes is made. For high voltage fast recovery diodes, the allowed maximum reverse voltage applied at 100 - 125 degC, cannot be applied above 150 degC, without instability of the electrical characteristic and risk of failure. In the case of similar standard recovery diodes, the same allowed maximum reverse voltage can be applied from 100 degC up to 175-200 degC junction temperature without instability. The instability manifested by visible thermal runaway of the electrical characteristic to higher and higher values of reverse current, is caused by the surface component flowing at the junction edge. Damage at the junction periphery has been found for the failed devices after instability. Performance improvement of fast recovery diodes at high temperature is possible by further reduction of the surface leakage current |
17,044 | Please write an abstract with title: Automatic Parkinson's tremor assessment with data analysis from daily activities, and key words: Parkinson's disease, Handheld computers, Social networking (online), Wearable computers, Sensor phenomena and characterization, Sensor systems, Real-time systems. Abstract: A new approach for the assessment of motor symptoms caused by Parkinson's disease (PD), based on data recorded using a smart mobile phone, is presented in this manuscript. Data were obtained from the online platform kaggle.com, and were analyzed based on machine learning techniques to produce a comprehensive physician report, presenting motor symptoms in everyday life. The idea of this study is to equip PD patients with a smartphone, which will monitor signals in real time for a period of time in order to enhance the medical diagnosis routine of a physician, providing information about the overall picture of the patient's motor condition, resulting in the provision of individualized treatment to the patient. |
17,045 | Please write an abstract with title: Phase Transition Analysis for Compressive Sensing Based DoA Estimation in Automotive Radar, and key words: Direction-of-arrival estimation, Estimation, Radar applications, Compressed sensing, Signal resolution, Signal to noise ratio, Automotive engineering. Abstract: In automotive radar applications, the compressive sensing (CS) based DoA estimation is used in array signal processing in recent years. Sparse reconstruction has the potential to estimate the direction of arrival (DoA) with super resolution. However, failed results may be acquired via sparse reconstruction in inappropriate conditions, namely the critical condition determining success or failure must be taken into consideration. In this paper, the sparsity of the scenario and the signal-to-noise ratio (SNR) are analyzed as the main factors via phase transition diagrams. Other factors affecting the success or failure are also investigated, such as the array configuration and the sparse recovery algorithm. Simulated and experimental results demonstrate the critical conditions, in which the DoA estimation is successful or failed. |
17,046 | Please write an abstract with title: Intelligent Controllers for Direct Self Control-SVPWM using Sample Orientation Phase Voltages, and key words: Transient response, PI control, Induction motors, Rotors, Interference, Stators, Harmonic analysis. Abstract: Recent advances in the controllers of Asynchronous motor (Induction motor) provide a path to the precise control of the drives which are being used in industrial applications. Among these technique’s vector control(FOC) of the drive is costly as such the feedback arrangement is complex and requires, encoder to determine the speed, along with using tradition PI controllers, to have a better solution and to reduce the cost Direct self-control(DSC) gained importance which requires less computation and feedback estimators. Though DSC suffers from harmonics introduced by the comparators, to reduce higher order harmonics SVPM is also used along with it. The variables present in the drives changes with respect to temperature and hence PI controllers cannot provide better solution in terms of its performance. To provide solution for the above problem, three Intelligent controllers ANFIS (adaptive neuro -fuzzy interference) with sample orientation phase voltages, are being incorporated. This proposed techniques improves the performance of electric drive and to validate the results the above techniques is simulated using MATLAB/SIMULINK |
17,047 | Please write an abstract with title: A Study of Plasmons in Optical Nano-Antennas, and key words: Gold, Optical polarization, Shape, Meetings, Resonant frequency, Plasmons, Electron optics. Abstract: An analytical model of the response of a free electron gas within a nano-antenna interacting with an electromagnetic wave with normal incidence was developed. By examining the longitudinal oscillations of the plasma in the nano-antenna, a relationship was obtained for the wavelengths generated by the plasmons in the nano-antenna. The nearfield amplitudes are expressed in an analytical way. Finally, the amplitudes of the scattered fields at a given distance from the nano-antenna are compared. It was shown how the intensity of the dispersed Electromagnetic Field decays as a function of the excitation modes and we see that these can be functions in the visible regime, a property sought in these devices for energy applications. |
17,048 | Please write an abstract with title: MIMO Radar Beampattern Design Based on Manifold Optimization Method, and key words: Manifolds, Interference, MIMO radar, Signal to noise ratio, Computational efficiency, Receiving antennas, Radio frequency. Abstract: The transmit beampattern design with constant modulus (CM) constraint is a key technical issue in Multiple-Input Multiple-Output (MIMO) radar system. The problem is non-convex and direct solution is impossible in general, due to the CM constraint. Usually, most existing methods indirectly solve this problem by relaxing it to a more tractable form. These methods usually either degrade the performance due to relaxation or consume expensive computational cost. Different from the relaxation methods, a direct method is proposed to solve the non-convex problem without relaxation. In the proposed method, the original problem is first converted to an Unconstrained Quadratic Lagrange Multiplier Problem (UQLMP) over the non-convex complex circle manifold. Then, by efficiently finding the descent direction and step size to ensure the objective function to be non-increasing, a novel Manifold Optimization-based Conjugate Gradient (MOCG) approach is derived to directly solve UQLMP. Compared with current methods, the proposed method has better performance in terms of nulling depth. |
17,049 | Please write an abstract with title: Performance Analysis of SSD and Faster RCNN Multi-class Object Detection Model for Autonomous Driving Vehicle Research Using CARLA Simulator, and key words: Analytical models, Computational modeling, Surveillance, Neural networks, Radar detection, Object detection, Robustness. Abstract: Autonomous vehicle research has grown exponentially over the years with researchers working on different object detection algorithms to realize safe and competent self-driving systems while legal authorities are simultaneously looking into the ways of mitigating the risks posed by fully autonomous vehicles. These advancements can result in a much safer commuting environment, reduced accidents and also eliminate the necessity for human driving. Recent developments in the field show that object detection models combined with an on-vehicle camera module provides more robustness and accuracy than other methods such as LiDAR or RADAR. This paper proposes two object detection algorithms, SSD and Faster RCNN for autonomous driving applications through various performance parameters. CARLA Simulator was used to generate synthetic data to train and test the models. Results shows that that Faster-RCNN was found to have a mean Average Precision (mAP) value of 94.32% while SSD has a mAP of 88.998%. However, SSD had a speed of 30 ms/image while Faster-RCNN had a speed of 106 ms/image. Taking into consideration the real-time and speed constraints in autonomous driving, it was inferred that the SSD algorithm is much better suited for this problem as the difference in accuracy between the models was relatively lesser compared to the difference in computation speeds. |
17,050 | Please write an abstract with title: New combinatorial methods for the improvement of the convergence speed and the tracking ability of the fast stable RLS adaptive algorithm, and key words: Convergence, Resonance light scattering, Adaptive algorithm, Finite impulse response filter, Transversal filters, Filtering algorithms, Wiener filter, Adaptive filters, Approximation algorithms, Speech. Abstract: In this paper, we present new versions of the fast RLS adaptive algorithm. These versions are based on a combination of the block filtering technique and a use of a scalar accelerator parameter in each block. These mixing techniques lead a faster convergence of the fast RLS algorithm and behave better with time-varying acoustic systems. The proposed versions have approximately the same complexity of calculation than the original version of the fast RLS algorithm. The difference between this work and the previous ones (Benallal A. et al., Jan 1989) is the use of a new combination techniques which provide new forms of the fast RLS prediction part. All the proposed versions and their simulations results are presented. |
17,051 | Please write an abstract with title: Dynamic map for obstacle avoidance, and key words: Mobile robots, Navigation, Testing, Histograms, Humans, Motion planning, Design engineering, Design methodology, Monitoring, Books. Abstract: Most of the existing obstacle avoidance algorithms work well in a relatively static environment, which consists of mostly stationary obstacles and maybe some slow-moving obstacles. In a dynamic environment, however, these obstacle avoidance algorithms may result in a robot colliding with a moving obstacle. In this paper, we propose an idea of constructing a dynamic map of obstacles that shows the predicted positions of the moving obstacles in future. It imitates the human actions of monitoring and estimating the movements of other objects in order to choose a suitable path for themselves to travel in a dynamic environment. We used this idea on an existing obstacle avoidance algorithm, the vector field histogram approach. The simulation results show that the resulting method is able to navigate a robot safely in a dynamic environment. |
17,052 | Please write an abstract with title: Robust Sampling Budget Allocation Under Deep Uncertainty, and key words: Optimization, Resource management, Uncertainty, Response surface methodology, Linear programming, Standards, Computational modeling. Abstract: A novel methodology is introduced for optimally allocating a sampling budget. Sampling budget allocation problems arise frequently in various settings. For example, in the design of complex engineering systems, given both the complexity of these systems and the imperfect information on new technologies, designers often face deep uncertainty as to system performance. Consequently, designers need to sample multiple alternative designs under a limited budget. This article proposes a minimax regret approach to allocate the sampling budget in the presence of deep uncertainty pertaining to system performance. The objective is to maximize the probability of selecting the design with the minimum–maximum regret under a limited sampling budget and imperfect information. To effectively solve the minimax regret problem, an approximation methodology that provides good solutions with quantifiable uncertainty is developed. The essence of the methodology, which has the added benefit of being generally applicable to any multilevel optimization, is that all but the first level of multilevel optimization can be eliminated via a response surface. By sampling many values of a higher level decision’s variables, solving the next lower level optimization given those samples values, and calibrating a response surface to the objective function value eliminate one required optimization. Doing this repeatedly reduces the complexity of the multilevel optimization to a standard optimization. Regardless of the number of levels in the optimization, repeating this process ultimately leaves one with a single optimization whose objective function can be directly computed, given the highest level variables. Numerical experiments with two sampling allocation examples demonstrate both the benefit of the robust sampling budget allocation versus nonrobust formulations and the effectiveness of the proposed solution approach. |
17,053 | Please write an abstract with title: A heuristic approach for design of easily testable PLAs using pass transistor logic, and key words: Programmable logic arrays, Logic design, Logic circuit testing, Design for testability. Abstract: In this paper, an improved design of easily testable PLAs has been proposed, based on input decoder augmentation using pass transistor (PT) logic along with improved conditions for product line grouping. The proposed technique primarily increases the fault coverage area of easily testable PLAs due to augmented PT and reduced testing time due to grouping the product lines. A simultaneous testing technique has been applied within the group that reduces the testing time. This approach ensures the detection of certain bridging faults, which were not considered by the existing techniques. A modified testing technique has also been presented in this paper. It is shown that the new grouping technique enhances the devices in all respects. |
17,054 | Please write an abstract with title: Land use and spatiotemporal pattern evolution of a mountain city agglomeration: A case study of the urban agglomeration in Dianzhong (central Yunnan), southwestern China, and key words: Economics, Analytical models, Spirals, Local government, Urban areas, Forestry, Market research. Abstract: Land use is attracting increasing amounts of attention in today's society. Taking the central Yunnan city cluster as an example, in this study, a quantitative method was used to study the evolution of land use and its spatial-temporal patterns. The results show that (1) in general, from 2000 to 2018, the area of construction land increased significantly, while the area of cultivated land and grassland decreased dramatically, and the area of woodland decreased slightly. In recent years, the water area increased, but the growth rate was slow and unstable, exhibiting a spiral growth trend. (2) From the perspective of land-use change, the overall rate of the land-use change in the study area was variable. For example, the rate of change of construction land was relatively fast compared with those of other land-use types. The rates of change of the forest area and water area were relatively slow. The drastic spatial changes in land use were mainly concentrated in the cultivated land, grassland, and construction land. The four types of land use experienced significant mutual transformations, among them, grassland, cultivated land, woodland, and construction land experienced the most significant transformations. (3) From the perspective of the evolution of the spatiotemporal pattern, the rate of change of the spatial patterns of all of the land-use types in the central Yunnan urban agglomeration increased, and the areas with drastic spatial changes were mainly concentrated in the grassland, arable land, and woodland. The construction land expanded in the northeast and southeast directions, which was related to the urbanization process and the regional economic development center of the central Yunnan urban agglomeration. |
17,055 | Please write an abstract with title: Estimating intrinsic image from successive images by solving underdetermined and overdetermined systems of the dichromatic model, and key words: intrinsic image, dichromatic model, singular value decomposition. Abstract: Estimating an intrinsic image from a sequence of successive images taken from an object at different angles of illumination can be used in various applications such as objects recognition, color classification, and the like; because, in so doing, it can provide more visual information. Meanwhile, according to the well-known dichromatic model, each image can be considered a linear combination of three components, including intrinsic image, shading factor, and specularity. In this study, at first, two simple independent constrained and parallelized quadratic programming steps were used for computing values of the shading factor and the specularity of each successive of images. In the algorithm mentioned above, only the mean and standard deviation of three channels for each pixel are required to solve the underdetermined problem of the dichromatic model equations. Then, the singular value decomposition method was used to estimate a unique intrinsic image through the values of the shading factor and the specularity of each of the images that constitute an overdetermined problem. The results of the successive reconstructed images using the estimated unique intrinsic image showed an increase in the visual assessment quality and color gamut of the final images. |
17,056 | Please write an abstract with title: Improving Code Summarization Through Automated Quality Assurance, and key words: Codes, Quality assurance, Filtering, Collaboration, Software reliability, Task analysis. Abstract: The code summarization task aims to generate brief descriptions of source code automatically. It is beneficial for developers to understand source code. However, almost all of current code summarization approaches may generate low-quality (BLEU4<40) summaries, which will mislead developers. Previous work has shown that it is possible to conduct quality assurance for document generation (QA4DG) and improve the practicability of document generation approaches. Code summarization can also be regarded as a document generation task. This work aims to investigate whether QA4DG approaches can be leveraged to improve code summarization. Specifically, we first investigate whether existing QA4DG approaches can be plugged in code summarization approaches. We find that an automated quality assurance framework for commit message generation named QACom performs best. In-spired by the idea behind QAcom, we propose an ensemble code summarization approach called Ensum. Precisely, given a code snippet, Ensum first uses current code summarization approaches to generate candidate summaries. Then, Ensum predicts the quality of each candidate summary using a collaborative filtering-based component and a retrieval-based component and selects the best candidate summary as the output. Experimental results on two public datasets show that Ensum outperforms three state-of-the-art single approaches and one ensemble approach for code summarization in terms of BLEU-4, METEOR, and ROUGE-L. |
17,057 | Please write an abstract with title: SAT vs. Substitution Boxes of DES like Ciphers, and key words: Ciphers, Conferences, Collaboration, Encoding, Testing. Abstract: One of the applied methods of symmetric ciphers investigations is cryptanalysis that uses the SAT problem. In this case, cipher testing starts with encoding the cipher's algorithm into a propositional Boolean formula. Then chosen randomly plaintext and cryptographic key are also encoded as formulas. Specialized to solve the SAT problem programs called SAT solvers can count the values of encrypted text for such input data. The final cipher analysis consists of providing the SAT solver with encoding formulas: plaintext and ciphertext. With such data, the SAT solver calculates the key value, i.e. performs cryptanalysis of the cipher with plaintext and ciphertext. In this work, we examine how SAT techniques behave for certain limited versions of the DES cipher and various types of S-boxes. To get the best result, we compared many, selected SAT solvers. |
17,058 | Please write an abstract with title: Polarization-insensitive beam splitters with variable split ratios based on phase gradient metasurfaces, and key words: Optical buffering, Optical variables control, Optical interferometry, Optical polarization, Optical reflection, Electric fields, Integrated optics. Abstract: We propose a polarization-insensitive beam splitter based on metasurface consist of cylinders with two types of phase gradients in the opposite directions. By changing the phase gradient, we found the incident light split into different directions. We set a phase buffer area to get different ratios of energy in the splitting direction to achieve adjustable splitting ratios from 0.2 to 1. This kind of beam splitter can be used in various optical systems such as multiplexers, interferometers for integrated optical circuits. |
17,059 | Please write an abstract with title: Innovation of the Chinese International Education Training Model Based on Situational Creation, and key words: Training, Computers, Technological innovation, Current measurement, Education, Information processing, Educational courses. Abstract: Chinese international education is an educational course that has been rising in recent years and is popular with other countries in the world. In Chinese international education, because of the particularity of the object of education, it is also required that the mode and form of education must be different from the domestic conventional education, and we should pay more attention to the creation and construction of the situation in the teaching process, so as to better cultivate students' Chinese language ability and promote the application and popularization of Chinese teaching abroad. Based on the oral teaching of Chinese international education, this paper briefly analyzes the concept of situational creation and its role in the oral teaching of Chinese international education, and puts forward the application measures of situational creation in the teaching process. |
17,060 | Please write an abstract with title: Convergence of a numerical algorithm for calculating optimal output feedback gains, and key words: Convergence of numerical methods, Output feedback, Automatic control, Control systems, Nonlinear equations, Iterative algorithms, Integral equations, Differential equations, Riccati equations, Stochastic processes. Abstract: A sequential numerical algorithm is described which obtains gains minimizing a broad class of performance indexes, including the standard LQ case. The primary contribution is a proof that the algorithm converges to a local minimum under nonrestrictive assumptions. Numerical examples illustrate the theory. The second example demonstrates an important LQ design technique which permits the designer to prespecify the feedback structure, subject to the requirement of output feedback stabilizability. |
17,061 | Please write an abstract with title: Complex multiple features tracking algorithm in motion capture, and key words: Tracking, Humans, Feature extraction, Testing, Motion analysis, Joints, Colored noise, Computer science, Video sequences, Predictive models. Abstract: To track complex multiple features in video sequences is always a challenging problem; we present a feature-tracking algorithm integrating feature recognition and feature matching in this paper. According to feature attributes and relationship among estimated features, extracted features are classified as four types of features. Then different quantitative matching strategies are applied to track different kinds of features. To verify the tracks, a cross correlation test and predicted 3D model based test are used to test and remove outliers. The contributions and characters of each attribute are considered in our algorithm. The experimental results demonstrate the efficiency of the presented motion-tracking algorithm. |
17,062 | Please write an abstract with title: Opto-thermally controlled beam steering in nonlinear all-dielectric metasurfaces, and key words: Geometry, Refractive index, Metasurfaces, Harmonic analysis, Laser excitation, Temperature control, Table lookup. Abstract: Metasurfaces have recently enabled a further miniaturization of many optical components which are typically bulky and made of different materials. Notably, nonlinear optics in dielectric metasurfaces has been investigated achieving significant Second Harmonic (SH) generation efficiency in χ (2) materials [1] , [2] . In this work, we use a symmetry broken meta-atom shaped as an AlGaAs "nano-chair", obtained by removing one quarter of the volume from a nanocylinder with elliptic base, see Fig. 1(a) . The proposed geometry is promising for technological applications, because capable of emitting the SH light along the vertical direction ( z axis) [3] . We thus propose to use such structures in a metasurface that is concurrently excited by a Fundamental Frequency (FF) pump in the infrared region (1.55 μm) and by a Continuous Wave (CW) beam in the visible (550 nm). By varying the CW intensity, it is possible to control the temperature inside the meta-atom. The temperature increasing is responsible for a modification in the AlGaAs refractive index. Thus, by varying the CW light intensity, I 0 , we can optimize the temperature profile so as to change the refractive index of the meta-atom, achieving in such manner the tuning of the linear resonant response and consequently obtaining a detectable variation in the SH light. In Fig. 1(b) we elucidate that is possible to create a look-up table for the emitted SH magnitude and phase coming from the meta-atom as a function of I 0 . We verify that for the studied CW intensity range, the SH emission pattern preserves a main lobe ( y -polarized) towards the vertical direction with small amplitude alterations. |
17,063 | Please write an abstract with title: KMUL: A User Identity Linkage Method across Social Networks Based on Spatiotemporal Data, and key words: Couplings, Social networking (online), Conferences, Big Data, Spatiotemporal phenomena, Trajectory, Time complexity. Abstract: With the increasing availability of spatiotemporal data, user identity linkage across social networks based on spatiotemporal data has attracted more and more attention. The existing methods have some problems, such as trajectory processing is not suitable for sparse data, grid based processing leads to information loss and anomaly, similarity threshold and other parameters are difficult to determine. To solve the above problems, we propose a k-means clustering based method KMUL to solve the problem of user identity linkage based on spatiotemporal data. According to the sparsity, heterogeneity and imbalance of spatiotemporal data in social networks, this method can represent the user identity as the form of cluster centers, and effectively link the user identity by calculating the distance between the cluster center representations. We compare this method with several state-of-the-art user identity linkage methods based on spatiotemporal data on real datasets, and the results show that this method outperforms the baseline methods in terms of effectiveness and efficiency. |
17,064 | Please write an abstract with title: TELUGU ANKELU: A Telugu Spoken Digits Corpora for Mobile Speech Recognition, and key words: Human computer interaction, Speech recognition, Speech processing, Older adults, Open source software, Faces, Automatic speech recognition. Abstract: Automatic Speech Recognition (ASR) deals with recognizing spoken words or sentences through an automated program or an algorithm. ASR has multi-faceted applications in various domains such as Mobile Speech Recognition, IoT, Human-Machine interaction, etc. Researchers have been working on different problems in these domains for more than 5 decades. Mobile speech recognition is a pre-dominant area that supports a wide variety of applications useful for physically challenged, senior citizens and novice mobile users. Though the domain has significant practicality, it faces challenges due to the lack of data in the targeted language. Though it is not major for well-developed languages like English, it is very profound in low-resourced and under-resourced languages. India has 1,391.99 million inhabitants speaking a wide variety of languages with Hindi being the most popular language. There are many native languages spoken in each region of the country. But, research that contributes towards the development of ASR is questionable due to many reasons, and the unavailability of data is one of those. Hence, an open-source speech digit data set has been prepared and will be available through this paper for the Telugu language which is the sixth largely spoken language in the country. |
17,065 | Please write an abstract with title: Optimal Offering of a Power Producer in Electricity Markets with Profile and Linked Block Orders, and key words: Electricity supply industry, Computational modeling, Regulation, Consumer electronics, Computational efficiency. Abstract: Block orders are increasingly adopted in many electricity markets as they enable power producers to implicitly express their unit commitment characteristics and address price volatility risks. However, previous work on the optimal offering problem of a price-taking producer participating in such markets has only considered the simplest type of block orders (regular block orders-RBO) and has neglected relevant realistic market regulations. This paper addresses these simplifications by proposing a new optimal offering model which also considers the more complex profile block orders (PBO) and linked block orders (LBO). This model is generic in that it can treat the block orders' time spans either as fixed parameters (following the modelling approach of previous work) or as endogenous decision variables, which constitutes a completely novel modeling approach. The presented case studies demonstrate that this novel approach yields a tremendously lower number of binary variables and more efficient computational performance, when PBO and LBO are considered. Furthermore, the case studies analyze the physical conditions under which the introduction of different types of block orders increases the examined producer's profit. |
17,066 | Please write an abstract with title: Antenna Aperture Tuning with High-Voltage Bulk-CMOS Switch-Based RF Capacitor, and key words: Capacitors, Switches, Radio frequency, Tuning, Antenna measurements, Feeds, Apertures. Abstract: A circuit for tuning the aperture of inverted-F antenna (IFA) utilizing a high-voltage RF-switch-based digitally-tunable capacitor in bulk-CMOS technology is demonstrated. The tuning network consists of the 5-bit switchable capacitor and a parallel inductor which are placed at the high-voltage plane of the radiating element with peak RF voltages of 60 V applied across the circuit. The antenna covers low and middle cellular frequency bands with fine tuning steps, providing return loss at the feed point of above 6 dB for more than 90% of the target frequency range. The measured peak reflected second and third harmonics generated by the tuned antenna when driven by the 34 dBm low-band RF signal are −38 dBm and −56 dBm respectively. |
17,067 | Please write an abstract with title: An analytical study of transport in a thermal interface material enhanced with carbon nanotubes, and key words: Organic materials, Carbon nanotubes, Thermal conductivity, Conducting materials, Thermal resistance, Thermal management of electronics, Resistance heating, Heat sinks, Geometry, Power dissipation. Abstract: Power dissipation in electronic devices is projected to increase over the next ten years to the range of 150-250 Watts per chip for high performance applications. One of the primary obstacles to the thermal management of devices operating at such high powers is the thermal resistance between the device and the heat spreader or heat sink that it is attached to. Typically the in situ thermal conductivity of interface materials is in the range of 1 to 4 W/mK, even though the bulk thermal conductivity of the material may be significantly higher. In an attempt to improve the effective in situ thermal conductivity of interface materials nano particles and nanotubes are being considered as a possible addition to such interfaces. This paper presents the results of an analytical and numerical study of transport in a thermal interface material that is enhanced with carbon nanotubes. The results from the analytical model are in excellent agreement with a numerical solution of the same geometry. Wide ranges of parametric studies were conducted to examine the effects of the thermal conductivity of the different materials, the geometry, and the size of the nanotubes. An estimate of the effective thermal conductivity of the carbon nanotubes was used, obtained from a molecular dynamics analysis. The numerical analysis was used to estimate the impact of imperfections in the nanotubes upon the overall system performance. Overall the nanotubes are found to significantly improve the thermal performance of the thermal interface material. The results show that varying the diameter of the nanotube and the percentage of area occupied by the nanotubes doesn't have any significant effect on the total temperature drop. |
17,068 | Please write an abstract with title: Anytime informed path re-planning and optimization for human-robot collaboration, and key words: Industries, Service robots, Collaboration, Modulation, Interference, Safety, Collision avoidance. Abstract: Robots working in proximity of humans often need to change their motion to avoid collisions and interference with the operators. This paper uses a path re-planning approach to change the robot path online when the human operator is in the robot way. The method exploits a set of pre-computed paths to compute a new feasible path in case of obstruction to enhance the trajectory’s readability. Moreover, the algorithm iteratively optimizes the current solution in an anytime fashion to deal with strict computing time requirements. Experimental results show the method’s effectiveness in a collaborative cell, compared with industry best practices. |
17,069 | Please write an abstract with title: Rendezvous Control of UAVs with Disturbance Compensation, and key words: Numerical simulation, Control systems, Robustness, Batteries, Quadrotors. Abstract: This paper describes the method of rendezvous control of UAVs under disturbance conditions. The quadrotor, which is used globally, has restrictions on the cruise distance, the cruise speed, and the flight time due to its structure and battery life. To overcome these problems, the coordination between the quadrotor and the fixed-wing UAV that is superior to the cruise speed and the long-range flight has been proposed by some researchers. If the quadrotor realizes the rendezvous docking to the fixed-wing UAV, the use range of the quadrotor expands extremely. However, these controllers are insufficient to have robustness against disturbances, although wind disturbance greatly influences these UAVs. Thus, this paper proposes the control method with disturbance compensation for the rendezvous problem for those UAVs. The artificial potential field (APF) is applied to the guidance of UAVs for the rendezvous. The effectiveness of the proposed method is confirmed numerically under the flight condition with the existence of the disturbance. |
17,070 | Please write an abstract with title: On the constraints of galaxy assembly bias in velocity space, and key words: galaxies: statistics, large-scale structure of Universe, cosmology: observations. Abstract: If the formation of central galaxies in dark matter haloes traces the assembly history of their host haloes, in haloes of fixed mass, central galaxy clustering may show dependence on properties indicating their formation history. Such a galaxy assembly bias effect has been investigated previously, with samples of central galaxies constructed in haloes of similar mass and with mean halo mass verified by galaxy lensing measurements, and no significant evidence of assembly bias is found from the analysis of the projected two-point correlation functions of early- and late-forming central galaxies. In this work, we extend the investigation of assembly bias effect from real space to redshift (velocity) space, with an extended construction of early- and late-forming galaxies. We carry out halo occupation distribution modelling to constrain the galaxy–halo connection to see whether there is any sign of the effect of assembly bias. We find largely consistent host halo mass for early- and late-forming central galaxies, corroborated by lensing measurements. The central velocity bias parameters, which are supposed to characterize the mutual relaxation between central galaxies and their host haloes, are inferred to overlap between early- and late-forming central galaxies. However, we find a large amplitude of velocity bias for early-forming central galaxies (e.g. with central galaxies moving at more than 50 per cent that of dark matter velocity dispersion inside host haloes), which may signal an assembly bias effect. A large sample with two-point correlation functions and other clustering measurements and improved modelling will help reach a conclusive result. |
17,071 | Please write an abstract with title: Delay limited optimal and suboptimal power and bit loading algorithms for OFDM systems over correlated fading channels, and key words: Delay, Fading, Quality of service, OFDM modulation, Bit error rate, Cross layer design, Wireless communication, Linear programming, Next generation networking, Wireless networks. Abstract: This paper explores optimal and suboptimal power and bit loading algorithms for a multicarrier system. Specifically, we study the trade-offs between the total transmit power of an orthogonal frequency division multiplexing (OFDM) system and the buffering delay of the packets in a transmission buffer. The loading framework is formulated as a Markov decision process (MDP) and an optimal loading policy which minimizes the transmit power while meeting a target delay constraint is obtained via equivalent linear programming (LP) methodology. The complexity of finding the optimal loading policy and its' implementation issues are described. Since finding the optimal policies becomes complex and practically un-realizable for large number of carriers in the system, we offer a sub-optimal power and bit loading algorithm using the results of the single carrier system's power and rate adaptation policy and a greedy approach. Selected numerical examples show that the sub-optimal algorithm, which has reduced complexity, has performance close to the optimal one. |
17,072 | Please write an abstract with title: Decentralized identity authentication and key management scheme, and key words: Authentication, Public key, Encryption, Ciphers. Abstract: SM9 is an identity-based cryptography and constitutes an important part of Chinese commercial cryptography system. It can avoid the complicated PKI system certificate management problems and provides new solution for IoT (Internet of Things) security applications. But SM9 needs the trusted third party KGC (Key Generator Center) to generate and manage the key for the user. So, key update is very troublesome. In order to solve the problem of SM9 key update, this paper proposes a decentralized identity authentication and key management scheme using block chain technology. In the scenario, the user only needs the IGC (Identity Generator Center) to generate its identifier and the key for the first time. Then, the user can automatically update the key. In the process, identifier remains the same as public key and only the private key and parameters update, so it is quite convenient for identity authentication. This paper redefines data structure of the transaction and each key update process is recorded in the chain blocks in the form of transaction. The block chain can guarantee the security and reliability of key update process since it can't be tampered with. The research in this paper is quite valuable for the identity authentication and key management in decentralized IoT application scenarios. |
17,073 | Please write an abstract with title: Optimal Allocation and Operation Strategies of Distributed Vanadium Redox Battery Energy Storage System, and key words: Analytical models, Costs, Vanadium, Redox, Batteries, Social intelligence, Resource management. Abstract: This paper presented an optimal allocation of distributed vanadium redox battery (VRB) energy storage system (ESS) in active distribution networks (ADNs). Correspondingly, an optimal method of distributed VRB ESS determining the rated power, rated capacity and operation strategies is proposed. Firstly, according to the different operation requirements, several corresponding operation strategies are proposed, also the operation process and constraints of the ESS unit are analyzed. Then, an operation benefit model of the ADNs is constructed, and the operation status of the ADNs allocated with the distributed VRB ESS is intuitively represented by the economic benefit. Finally, the proposed optimal allocation method of distributed VRB ESS considering multiple operation strategies is tested with an experimental case, which verifies the correctness and rationality of the proposed optimal allocation method. The results show that the operation benefits of the ADNs can be increased by 32% by determining the optimal allocation and appropriate operation strategy proposed in this paper. |
17,074 | Please write an abstract with title: The Effect of Direct-to-Reverberant Energy Ratio on Front-Back Confusion in Binaural Reproduction, and key words: Loudspeakers, Solid modeling, Three-dimensional displays, Azimuth, Distance measurement, Reliability, Task analysis. Abstract: The effect of direct-to-reverberant ratio (DRR) on front-back confusion in binaural reproduction was investigated. Binaural room impulse responses (BRIRs) of loudspeakers at 0° and 180° azimuths from the listening position were captured in an ITU-R BS.1116-3-comp1iant listening room (RT=0.25s) using a KU100 dummy head placed 2m away from each loudspeaker. The DRRs of the original BRIRs were manipulated by varying the levels of the reverberant parts (beyond 2. 5ms after the direct sound) of the signals, producing BRIRs with DRRs ranging from −12 dB to 12 dB with 4 dB intervals for each source position, as well as a pseudo-anechoic HRIR condition. Five subjects participated in the initial listening test. Each front or back stimulus with a different DRR was presented 20 times in a random order and the subject’s task was to respond either Front or Back. From psychometric functions derived from the data collected, a consistent pattern was observed from all subjects in that a lower DRR (more reverberant) tended to cause a higher rate of front-to-back confusion, whereas a higher DRR produced a higher rate of back-to-front confusion. The DRR thresholds of discrimination were different between the front and rear located sources, and the region between the two thresholds is proposed as a transition region where an extreme chance of confusion can be avoided for both source positions. |
17,075 | Please write an abstract with title: Hybrid energy storage lifetime-oriented control strategy in islanded microgrids: A real time simulation case study, and key words: Renewable energy sources, Smart cities, Microgrids, Production, Real-time systems, Batteries, Flywheels. Abstract: To reduce greenhouse gas emissions, volatile energy production from renewable sources is highly encouraged by international agreements. This leads to balancing challenges of demand and supply which can be addressed with smart grids or even smart city concepts. Demand side management control strategies for flexibility harvesting often include energy storage systems, like flywheel- (FESS) and battery (BESS) storages. To investigate different control strategies for a hybrid energy storage system with a flywheel and battery storage in an islanded microgrid, an existing flywheel is modernized with state-of-the-art components to support real time power hardware in the loop simulations. Testing a load levelling control strategy with this test bench showed that the cyclic lifetime of the battery storage system could be increased with peak shaving due to a reduced amount of charging and discharging operations. An excessive energy buffering control method could increase the islanded operation time by using nearly 10% of the otherwise lost energy. However, these results with the testbench showed limited use for research with the current setup due to low capacity and high self-discharge rate of the existing FESS. But due to the MATLAB-based programming interface, it is perfectly suitable as an educational setup for the demonstration of possible implementations of the European Green Deal. |
17,076 | Please write an abstract with title: A Study on Decentralized Autonomous Organizations Based Intelligent Transportation System enabled by Blockchain and Smart Contract, and key words: Visualization, Uncertainty, Decentralized autonomous organization, Transportation industry, Smart contracts, Transportation, Market research. Abstract: With the rapid development of the transportation industry, Intelligent Transportation System (ITS) tries to adapt to industry changes through constructing new organizational forms, management methods, and incentive mechanisms. However, many new governance issues have arisen due to the transportation system’s complexity, diversity, and uncertainty. DAO(Decentralized autonomous organization) enabled by blockchain and smart contracts are regarded as effective methods to solve the organizational governance problems for complex systems. Therefore, this article analyzes the main issues currently faced by ITS. Then, this paper proposed a 6-layer DAO structure framework for ITS and discussed its key research issues. Finally, a case study for the Macau transportation system is carried out, and further research directions are proposed. The DAO-based transportation system will represent the future trend of ITS development. This paper aims to motivate more discussion for this new direction and provide helpful guidance and reference for future research work. |
17,077 | Please write an abstract with title: Erbium Fiber Laser with 340 nJ, 63 fs Pulses from Standard Single Mode Telecom Fiber, and key words: Limiting, Europe, Erbium-doped fiber lasers, Laser modes, Ultrafast electronics, Telecommunications, Delays. Abstract: Femtosecond fiber lasers in the anomalous dispersion regime, such as Er and Tm lasers with wavelengths longer than 1.3 μm, rely on nonlinearity for spectral broadening and pulse compression. At high intensities, the nonlinearity becomes uncontrolled, limiting maximum output. For an all-fiber Er laser, the record pulse energy is 34 nJ, in 12/130, likely multimode, fiber [1] . Divided pulse amplification has increased that to 60 nJ [2] by reducing the peak power in the fiber. Rather than alter the system to reduce peak power, our approach is to use a simple phase shaping method to delay pulse collapse, enabling increased pulse energy without a comparable increase in spectral broadening and temporal compression. |
17,078 | Please write an abstract with title: Process-data-warehousing-based operator support system for complex production technologies, and key words: Production systems, Manufacturing processes, Manufacturing automation, Decision support systems, Spread spectrum communication, Process design, Information systems, Joining processes, Data warehouses, Data analysis. Abstract: Process manufacturing is increasingly being driven by market forces, customer needs, and perceptions, resulting in more and more complex multiproduct manufacturing technologies. The increasing automation and tighter quality constraints related to these processes make the operator's job more and more difficult. This makes decision support systems (DSSs) for the operator more important than ever before. A traditional operator support system (OSS) focuses only on specific tasks that are performed. In the case of complex processes, the design of an integrated information system is extremely important. The proposed data-warehouse-based OSS makes possible linking complex and isolated production units based on the integration of the heterogenous information collected from the production units of a complex production process. The developed OSS is based on a data warehouse designed by following the proposed focus-on-process data-warehouse-design approach, which means stronger focus on the material and information flow through the entire enterprise. The resulting OSS follows the process through the organization instead of focusing separate tasks of the isolated process units. For human-computer interaction, front-end tools have been worked out, where exploratory data analysis and advanced multivariate statistical models are applied to extract the most informative features of the operation of the technology. The concept is illustrated by an industrial case study, where the OSS is designed for the monitoring and control of a high-density polyethylene (HDPE) plant. |
17,079 | Please write an abstract with title: Multisector Parabolic Equation Method for Scattering From Impenetrable Objects in Fluid Waveguides, and key words: Mathematical model, Scattering, Acoustic waveguides, Computational modeling, Benchmark testing, Standards, Media. Abstract: Parabolic equation methods are a robust and efficient tool for modeling long-range acoustic propagation in range-dependent waveguides. A lesser known, but equally effective, application of parabolic equations is to the scattering problem. In this paper, we study the applicability and accuracy of the multisector parabolic equation approach to scattering from impenetrable objects - first developed approximately two decades ago for convex objects and recently extended to more complex scatterers - in waveguides in two and three dimensions. We benchmark the method in two dimensions in a range-dependent waveguide consisting of two different fluid media and find very good agreement with finite element methods for both forward scattering and backscattering, including the case where the scatterer is located at the interface between the media. Finally, we provide an example of scattering in a large three-dimensional waveguide, which would be extremely computationally intensive using alternate approaches, but is practical using the parabolic equation method. |
17,080 | Please write an abstract with title: Extraction of Rotating Machine Sources for Fault Diagnostics using Independent Component Analysis, and key words: Rotating machines, Independent component analysis, Pollution measurement, Integrated circuit noise, Working environment noise, Condition monitoring, Data mining, Interference, Noise measurement, Fault detection. Abstract: In this paper we introduce the use of independent component analysis for extraction of machine signal from noisy measurements. ts. The presence of interference noise at the machine defect sificationlas- ification cause misclassification. Consequently, we present a flexible method using the independent component analysis with subband analysis sis for extraction of rotating sources. The proposed method utilizes ICA estimation of unifying structure, includes mutual information and time structure. If the signals have no time correlation, their complexity ty may be achieved by their entropies. We introduce an on-linegorithm,al- ithm, such as an alternative of the algorithm that includes mutual information and time-correlation. Simulation study shows that the combined scheme can effectively extract the signal of interest from the instantaneous and delayed mixtures with noise, in comparison with the conventional method and the proposed approaches. The performance ance of the proposed method is evaluated experimentally on aingbear- ng test bed data using the proposed method and the results show to provide more accurate defect analysis with noisy corrupted data over the conventional method. |
17,081 | Please write an abstract with title: Productivity formula of horizontal well with gas and water production in ultra-high pressure and low permeability gas reservoir, and key words: Productivity, Temperature sensors, Sensitivity, Temperature, Reservoirs, Skin, Permeability. Abstract: The determination of gas well productivity is the basis of scientific and reasonable development of gas fields and has important guiding significance for gas well production allocation. According to the change of gas-water two-phase seepage law, the productivity equation of horizontal well with gas-water production in low permeability gas reservoir was established based on the theory of steady seepage, which was affected by stress sensitivity, formation damage and high-speed non-Darcy. The results show that the effective thickness, horizontal section length, permeability and well radius are positively correlated with productivity, while the water saturation, stress sensitivity, well control radius, skin factor and formation temperature are negatively correlated, and the water saturation and stress sensitivity have a greater impact on productivity. |
17,082 | Please write an abstract with title: From feature scale simulation to backend simulation for a 100 nm CMOS process, and key words: CMOS process, Circuit simulation, Predictive models, Integrated circuit interconnections, Capacitance, Surfaces, Fabrication, Delay effects, Etching, Level set. Abstract: The current challenge for TCAD is the prediction of the performance of groups of devices, backends, and - generally speaking - large parts of the final IC, in contrast to the simulation of single devices and their fabrication. This enables one to predictively simulate the performance of the final device depending on different process technologies and parameters, which the simulation of single devices cannot achieve. In this paper, we focus on the simulation of backend, interconnect capacitance, and time delays. To that end, topography simulations of deposition, etching, and CMP processes in the various metal lines are used to build up the backend stack. The output of the feature scale simulations is used as input to a capacitance extraction tool, whose results are made available directly to the circuit designer. We discuss the utilized simulation tools and their integration. The topography simulations were performed by our tool called ELSA (enhanced level set applications) and the subsequent simulations by RAPHAEL. Finally simulation results for a 100 nm process are presented, where the influence of void formation between metal lines profoundly impacts the performance of the whole interconnect stack. |
17,083 | Please write an abstract with title: Efficient Identification of Linear Evolutions in Nonlinear Vector Fields: Koopman Invariant Subspaces, and key words: Dictionaries, Eigenvalues and eigenfunctions, Matrix decomposition, Mathematical model, Predictive models, Linearity, Approximation algorithms. Abstract: This paper presents a data-driven approach to identify finite-dimensional Koopman invariant subspaces and eigenfunctions of the Koopman operator. Given a dictionary of functions and a collection of data snapshots of the dynamical system, we rely on the Extended Dynamic Mode Decomposition (EDMD) method to approximate the Koopman operator. We start by establishing that, if a function in the space generated by the dictionary evolves linearly according to the dynamics, then it must correspond to an eigenvector of the matrix obtained by EDMD. A counterexample shows that this necessary condition is however not sufficient. We then propose a necessary and sufficient condition for the identification of linear evolutions according to the dynamics based on the application of EDMD forward and backward in time. Due to the complexity of checking this condition, we propose an alternative characterization based on the identification of the largest Koopman invariant subspace in the span of the dictionary. This leads us to introduce the Symmetric Subspace Decomposition strategy to identify linear evolutions using efficient linear algebraic methods. Various simulations illustrate our results. |
17,084 | Please write an abstract with title: An FPGA Based Reconfigurable Coprocessor Board Utilizing a Mathematics of Arrays, and key words: Field programmable gate arrays, Coprocessors, Mathematics, Hardware, High performance computing, Computer architecture, Prefetching, Heat transfer, Equations, Application software. Abstract: Work in progress at the University of Missouri-Rolla on hardware assists for high performance computing is presented. This research consists of a novel field programmable gate array (FPGA) based reconfigurable coprocessor board (the Chameleon Coprocessor) being used to evaluate hardware architectures for speedup of array computation algorithms. These algorithms are developed using a Mathematics of Arrays (MOA). They provide a means to generate addresses for data transfers that require less data movement than more traditional algorithms. In this manner, the address generation algorithms are acting as an intelligent data prefetching mechanism or special purpose cache controller. Software implementations have been used to provide speedups on the order of 100% over classical methods to the solution of heat transfer equations on a uniprocessor. We extend these methods to application designs for the Chameleon Coprocessor. |
17,085 | Please write an abstract with title: Selective Clock Gating Based on Comprehensive Power Saving Analysis, and key words: Multiplexing, Feedback loop, Circuits and systems, Clocks, Flip-flops. Abstract: Clock gating saves dynamic power by shutting off a subtree of clock network during the idle state of the driven logic blocks. This paper proposes a new clock gating methodology based on a precise power saving analysis to overcome the ineffectiveness of the conventional logic structure based clock gating. Two new features exploited in our proposed clock gating are (i) the multiplexer selection signal probability that a flip-flop with multiplexer feedback loop receives a new input and (ii) the joint probability of selection signals that two flip-flops with different multiplexor selection signals both receive new inputs at the same clock cycle. |
17,086 | Please write an abstract with title: Integrated CNT Aerogel Absorbers for Sub-THz Waveguide Systems, and key words: Microwave measurement, Absorption, Rectangular waveguides, Microwave theory and techniques, Loss measurement, Dielectric measurement, Frequency measurement. Abstract: The ongoing development of sub-THz systems and applications has created a need for new absorbing materials which can be integrated in a simple, low-cost manner. Here, we investigate the properties of CNT-based aerogels in the range of 67–110 GHz and develop a simple technique for their integration. The aerogels are synthesised using standard techniques and then shaped using a laser cutter to allow for direct integration. The S-parameters of a total of four aerogel absorber samples are measured. The absorbers offer a return loss of up to 12 – 14.5 dB across the measurement band, with a maximum absorption of 5 dB/mm. The observed performance makes CNT aerogels extremely promising candidates for use in sub-THz waveguide systems and applications. |
17,087 | Please write an abstract with title: Cell Load and Resource-aware Flow Shifting Scheme based on Heterogeneous Mobile Networks Data, and key words: 5G mobile communication, Urban areas, Disaster management, Telecommunications, Information and communication technology, Resource management. Abstract: In the past decade, 4G networks have been widely deployed, meanwhile, 5G networks start to deploy recently. 4G and 5G heterogeneous mobile networks envisage the challenge of imbalanced user distribution with uneven resource utilization. Above challenge will become deteriorated under emergency scenarios (e.g., disaster, crisis). In order to address the imbalanced user distribution with uneven resource utilization, this paper designs a novel 4G/5G heterogeneous mobile networks data (HMND) system. On the basis of this HMND system, we propose cell load and resource-aware flow shifting (CLRFS) scheme. The HMND system and CLRFS scheme are deployed in a city to verify the performance. Results show that the HMND system and CLRFS scheme can evaluate both the 4G cells and 5G cells precisely, as well as assist telecom operator to shift traffic among 4G and 5G. |
17,088 | Please write an abstract with title: 40 GHz optical clock extraction from 160 Gbit/s data signals using PLL-based clock recovery, and key words: Clocks, Data mining, Optical receivers, Optical interferometry, Optical filters, Optical pulse generation, Repeaters, Multiplexing, Phase locked loops, Signal generators. Abstract: In summary, we have demonstrated 40 GHz optical clock extraction from 160 Gbit/s input data signals by introducing an optical multiplexer to an optical phase locked loop (PLL) based on a semiconductor laser amplifier in a loop mirror (SLALOM). We obtained RMS timing jitter of less than 0.3 ps for a wide range of data input powers. We also investigated 80 GHz and 160 GHz clock extraction and showed that the SLALOM operates as phase comparator for clock signals up to 160 GHz. Thus this clock recovery can also be applied for 160 Gbit/s 3R-regeneration. |
17,089 | Please write an abstract with title: Secure network design: A layered approach, and key words: Protocols, Standardization, Information security, Authentication, Computer security, Computer networks, Network servers, Error correction, Costs, Terminology. Abstract: Security solutions for networks typically appear as single protocols, or protocols that correspond to a single layer of the OSI network reference model (protocol stack). The result is a wide variety of protocols which provide solutions to very specific problems and environments. In this paper, we introduce an architecture for secure networks, which is based on layers, in analogy to the OSI protocol stack Adoption of a layered approach leads to many advantages in secure network design: modularity, flexibility, ease of standardization, etc. We introduce a reference model with 4 layers and argue that it is suitable for conventional network architectures. We present how layers of the secure network reference model correspond to layers of the OSI protocol stack, and we demonstrate that use of the layers leads to security solutions that resolve several problems of existing security protocols. |
17,090 | Please write an abstract with title: IEEE Transactions on Nuclear Science 2021 Best Paper Award, and key words: Awards. Abstract: The IEEE Transactions on Nuclear Science (TNS) Best Paper Award is an annual award recognizing the most significant paper published in the Transactions in a given year. The Award is sponsored by the IEEE Nuclear and Plasma Sciences Society and the winning paper is selected according to its quantifiable usefulness to the community. The authors of the papers published in the Transactions in the third year prior to the year of the award are eligible for consideration. The 2021 award is, therefore, awarded to the paper published in the calendar year 2018, judged to be the most useful to our community based on metrics calculated for the years 2018–2020. |
17,091 | Please write an abstract with title: Wine Quality Classification using Physicochemical Properties along with Extreme Learning Machines, and key words: wine classification, wine quality, extreme learning machines, physicochemical properties. Abstract: Chilean wine is one of the most consumed in the global market due to its excellent quality and wide variety of grape crops throughout the country, with Chile being the largest exporter of wine in the southern hemisphere. The characterization of wine quality is of vital importance for this industry, as the valuation of this product in the market depends on it. This study proposes the binary classification of wine quality (high and low quality) for both white and red varieties. To do this, we used Extreme Learning Machine (ELM) due to its training speed and acceptable performance. The evaluated ELMs are Basic ELM, Regularized ELM, and Unbalanced ELM. The results of these algorithms were measured in terms of Accuracy, Geometric Mean, and complexity expressed in training time. When comparing the performance results of these algorithms, it can be stated that the different types of ELMs have similar performance, with the Unbalanced ELM having the best performance, with almost 80 % accuracy for white varieties and 87 % accuracy for red varieties along with learning speed in the order of seconds. This research demonstrates the viability and potentiality of using ELMs for the classification of wine quality for both white and red varieties. |
17,092 | Please write an abstract with title: A Memetic Algorithm for Curvature-Constrained Path Planning of Messenger UAV in Air-Ground Coordination, and key words: Memetics, Heuristic algorithms, Maintenance engineering, Traveling salesman problems, Unmanned aerial vehicles, Path planning, Vehicle dynamics. Abstract: This paper addresses a UAV path planning problem for a team of cooperating heterogeneous vehicles composed of one unmanned aerial vehicle (UAV) and multiple unmanned ground vehicles (UGVs). The UGVs are used as mobile actuators and scattered in a large area. To achieve multi-UGV communication and collaboration, the UAV serves as a messenger to fly all UGVs to transmit information. The path planning of messenger UAV is formulated as a Dynamic Dubins Traveling Salesman Problem with Neighborhood (DDTSPN). A novel memetic algorithm is proposed to find the shortest route enabling the UAV to fly over all requested UGVs. In the memetic algorithm, the combination of genetic algorithm and local search is employed to find a high-quality solution in a reasonable time, and a gradient-based repair strategy is used to repair the individuals violating dynamic constraints. The calculation results on both small and large instances show that the proposed method can generate high-quality solutions as compared with the state-of-the-art algorithms. |
17,093 | Please write an abstract with title: Review on Solid-State-Based Marx Generators, and key words: Generators, Topology, Inductors, Capacitors, MOSFET, Insulated gate bipolar transistors, Pulse modulation. Abstract: Marx generators are widely used to produce transient high-voltage pulses. The evolution of semiconductor devices and power electronics concepts promotes the development of solid-state Marx generators (SSMGs) and enables them with flexible pulse modulation ability. First, this article sorts out the evolution of SSMGs topologies chronologically. We can see that how the energy efficiency of SSMGs is considerably improved by replacing resistors with diodes and switches and how square-wave pulses are generated by SSMGs based on half-bridge structures. Unipolar and bipolar pulses can be easily produced with different SSMGs. Second, we discuss the influence of rated voltage and rated power of present semiconductor switches on the performances of SSMGs since switches are the key components in pulse generators. To reduce the size and weight of SSMGs, metal–oxide–semiconductor field-effect transistors (MOSFETs) and insulated gate bipolar transistors (IGBTs) with small packages are preferable. Third, synchronous isolated driving of switches as the crucial technique in SSMGs is introduced. Different methods of providing synchronous signals and isolated power to various stages in SSMGs are illustrated. Fourth, the performance including load capacity, droop compensation, waveform modulation, and self-triggering of SSMGs is discussed. In the end, the developing trend of SSMGs is given. |
17,094 | Please write an abstract with title: Synthetic Dimension Photonics on a Si CMOS Platform, and key words: Time-frequency analysis, Frequency modulation, Resonant frequency, Lattices, Ring lasers, Silicon, Time-domain analysis. Abstract: We present a dynamically modulated ring resonator on a Si CMOS platform, hosting a synthetic dimension lattice over 180 GHz. The frequency and time domain synthetic band structure was acquired and photonic transport phenomena were explored. |
17,095 | Please write an abstract with title: Desarrollo de un sistema para el registro de variables termodinámicas en un equipo de enfriamiento [Not available in English], and key words: Monitoring, Biomedical monitoring, Spreadsheet programs, Data visualization, DH-HEMTs, Tools, Surges. Abstract: No English translation of this document was provided by the author or conference organizers. |
17,096 | Please write an abstract with title: Machine Learning Approaches for Cancer Bone Segmentation from Micro Computed Tomography Images, and key words: Bones, Computed tomography, Lesions, Cancer, Forestry, Image edge detection, Machine learning. Abstract: Many types of cancers such as multiple myeloma cause bone destruction, resulting in pain and fractures in patients and increased fatality. To quantify the degree of bone disease caused by cancer and analyse treatment response for bone repairing, accurate knowledge of the volumetry of all lesions is needed. To this end, this study proposes to apply two main approaches to the segmentation of bone lesions in cancer-induced bone disease from Micro Computed Tomography (μCT) images - structured forest-based edge detection approach and deep learning approach. A fast edge detection approach with structured forest, an extension of [1], is applied to identify the volumetry of all lesions in mice tibia, where the obtained results are evaluated against the manually labelled data, demonstrating the efficiency of the compared approaches. The Gaussian processes (Convnet GP) approach has achieved the best performance among the compared approaches, with 99.6% intersection of union and 99.7% precision. Our results demonstrate that the developed approach provides a reasonable delineation of the samples, showing the great potential towards fully automatic bone tumour segmentation. |
17,097 | Please write an abstract with title: Top-k User-Based Collaborative Recommendation System Using MapReduce, and key words: Web services, Collaborative filtering, Scalability, Clustering algorithms, Cluster computing, Big Data, Filtering algorithms. Abstract: Collaborative Filtering (CF) methods are widely used in recommender systems. However, due to the high computational complexity of CF, the existing algorithms do not scale well when the number of users and items grow. In this paper, we develop a new user-based collaborative filtering method using the MapReduce framework to recommend top-k items for each user in a given dataset. Our proposed method requires a dataset that contains item numbers, user ids, and ratings. We applied our proposed method to recommend movies using the MovieLens dataset. We implement our proposed algorithms on Apache Spark running on Amazon Web Services (AWS) clusters. We perform experiments on different cluster sizes to demonstrate the scalability of our proposed method. The experimental results show that the proposed method is highly scalable and exhibits near-linear speed-up when we increase the number of clusters. |
17,098 | Please write an abstract with title: Research on Linear Active Disturbance Rejection Control of Linear Motor XY Motion Platform, and key words: Force, Permanent magnet motors, Synchronous motors, Mathematical model, Feedforward systems, Control systems, Friction. Abstract: Linear motors are widely used in semiconductor packaging equipment to achieve high-speed and high-acceleration linear motion as well as high positioning accuracy. The linear motor XY motion platform is an essential component of semiconductor packaging equipment and consequently, the improvement of its motion performance is of great significance to the packaging industry. The active disturbance rejection controller (ADRC) is the controller which not only inherits the advantages of traditional PID controller which decreases tracking errors based on tracking errors, but also can make system realize high response speed and small overshoot at the same time. The linear active disturbance rejection controller (LADRC) is a linear simplified ADRC with the characteristics of easier parameter tunning. In this paper, LADRC is proposed to be used in the linear motor XY motion platform servo system. System dynamics and disturbances are observed by the linear extended state observer (LESO) and compensated to improve interference rejection capability and stability of the servo system. Besides, the feedforward controller (FFC) is adopted to improve the response speed of the XY platform. A simulation model of the linear motor XY motion platform control system is established to verify the validity of LADRC. Disturbances are applied to the PID, LADRC and LADRC with FFC models respectively. Motion performances under these three situations are compared. The results show that compared with the PID control, linear active disturbance rejection control combined with feedforward compensation can improve the tracking performance and anti-interference ability of the system. |
17,099 | Please write an abstract with title: Call for Nominations AAAI Squirrel AI Award for Artificial Intelligence for the Benefit of Humanity, and key words: Awards. Abstract: Reports on guidelines for various CS society awards. |
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