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11,800 | Please write an abstract with title: Accelerated Intravascular Ultrasound Imaging using Deep Reinforcement Learning, and key words: Image quality, Measurement, Ultrasonic imaging, Navigation, Magnetic resonance imaging, Reinforcement learning, Signal processing. Abstract: Intravascular ultrasound (IVUS) offers a unique perspective in the treatment of vascular diseases by creating a sequence of ultrasound-slices acquired from within the vessel. However, unlike conventional hand-held ultrasound, the thin catheter only provides room for a small number of physical channels for signal transfer from a transducer-array at the tip. For continued improvement of image quality and frame rate, we present the use of deep reinforcement learning to deal with the current physical information bottleneck. Valuable inspiration has come from the field of magnetic resonance imaging (MRI), where learned acquisition schemes have brought significant acceleration in image acquisition at competing image quality. To efficiently accelerate IVUS imaging, we propose a framework that utilizes deep reinforcement learning for an optimal adaptive acquisition policy on a per-frame basis enabled by actor-critic methods and Gumbel top-K sampling. |
11,801 | Please write an abstract with title: C-band GaAs FET power amplifiers with 70-W output power and 50% PAE for satellite communication use, and key words: Power amplifiers, Gallium arsenide, FETs, Power generation, Satellite communication, Pulse amplifiers, High power amplifiers, HEMTs, MODFETs, Pulse measurements. Abstract: This paper describes a successfully developed high-power and high-efficiency C-band GaAs FET amplifier for satellite communication systems. To realize high efficiency in a high-power amplifier, an HFET well-designed for high-power applications is developed, and precise design for an amplifier is carried out. The HFET employed achieves reduction in a gate leakage current while maintaining a high maximum drain current. For precise design of an amplifier, large-signal FET model parameters are extracted using pulsed I-V and S-parameter measurements. Based on this model, second harmonic impedances as well as fundamental impedances are determined for obtaining high efficiency and input- and output-matching circuits which are assembled in a compact package are designed to achieve a high-efficiency internally matched amplifier. As a result, the amplifier delivers a high saturated output power of 70 W and a high power-added efficiency of 51%. These characteristics are the record power performance in C-band in terms of simultaneous achievement of high power and high efficiency. A low third order intermodulation distortion of -35 dBc is also obtained at a drain voltage of 10 V. |
11,802 | Please write an abstract with title: Experimental comparison of hybrid and proactive MANET routing protocols, and key words: Mobile ad hoc networks, Routing protocols, Network topology, Laboratories, Testing, Internet, Spine, Communication system traffic control, Ad hoc networks, Bandwidth. Abstract: The paper describes an experimental implementation of a QoS-aware hybrid routing protocol that uses a flexible mix of proactive and reactive routing techniques within mobile ad hoc networks (MANETs). After a brief review of the benefits and applications of proactive, reactive (on-demand) and hybrid routing, the architectural details and protocol operation of Scientific Research Corporation's "wireless ad hoc routing protocol" (WARP) are given. The paper then discusses the laboratory testing methodology used during the development of WARP, and gives an experimental comparison of WARP with a proactive routing protocol, namely optimized link state routing (OLSR). |
11,803 | Please write an abstract with title: TFARMA models: order estimation and stabilization, and key words: Time frequency analysis, Signal processing algorithms, Random processes, Filters, Iterative algorithms, Technological innovation, Radio frequency, Reflection, Delay effects, Parameter estimation. Abstract: The time-frequency ARMA (TFARMA) model is introduced as a time-varying ARMA model for nonstationary random processes that is formulated in terms of time shifts and frequency (Doppler) shifts. We present Akaike and minimum description length information criteria for the practically important task of selecting the TFARMA model orders. Because the estimated inverse filter used by the resulting order selection procedures is not guaranteed to be stable, we propose an iterative stabilization algorithm that is based on the concepts of instantaneous roots and root reflection/shrinkage. The performance of the proposed order selection and stabilization techniques is assessed through simulation. |
11,804 | Please write an abstract with title: Security mechanisms maintaining user profile in a personal area network, and key words: Intelligent networks, Personal area networks, Communication system security, Data security, Authentication, Wide area networks, Network topology, Mobile communication, National security, Computer networks. Abstract: A personal area network environment is a wireless ad hoc data communication system that allows a number of independent data devices to communicate. A more and more wireless devices will be used in the near future. These devices form an ad-hoc environment whose security issues are very critical. The robustness and adaptability will become the key issues to accomplish security in ad hoc wireless network. Security should be applied in all levels of the system, but main concern of this paper is to tackle this issue mainly by means of secure communication in higher layers and how it could be possible to maintain the user profile and share specific services and application with other PANs. There is a need of enhanced security via application in order to achieve seamless communication between several devices not only over the same personal area network. Some desirable properties such as authentication and privacy that can prevent the information of the users from flowing to others is considered through this application. |
11,805 | Please write an abstract with title: Small-Signal Modeling and Stability Analysis of MMC with the Consideration of Circulating Current Suppression Controller, and key words: Mathematical model, Harmonic analysis, Stability analysis, Analytical models, Voltage control, Current control, Modulation. Abstract: This paper proposes a modular multilevel converter (MMC) small signal modeling method based on the harmonic state space (HSS) method, which considers the circulating current suppression controller in DC voltage control mode. This modeling method could achieve high accuracy since it considers complex internal dynamic characteristics. The stability of the MMC system and the influence of the circulating current suppression controller are estimated through the eigenvalues analysis to improve the design efficiency of the control system. Finally, time-domain simulation is provided in MATLAB/Simulink to verify the accuracy of the HSS small signal model and the validity of the theoretical stability analysis. |
11,806 | Please write an abstract with title: Modified Efficient Parallel Distributed Arithmetic based FIR Filter Architecture for ASIC and FPGA, and key words: Distributed Arithmetic, FPGA, ASIC, FIR Filter, Multiplierless. Abstract: Digital FIR filters can be efficiently implemented using distributed arithmetic (DA). Original DA provides low throughput. Parallel DA is proven to be a promising technique for efficient DA implementation. Block-based parallel DA architecture proposed by Singhal and Mohanty is examined and improved by applying a modified LUT decomposition scheme. Experiments with different levels of LUT decomposition are performed with FIR filters of orders 16 and 32. The proposed architectures are implemented in Basys-3 (Artix-7, XC7A35T-1CPG236C) FPGA board. Several critical performance metrics such as the number of slices, maximum clock frequency, dynamic power consumption, and throughput are estimated for different filter orders for the targeted FPGA Board. The proposed architecture is also implemented for ASIC using a 45 nm NanGate open cell library and area, power, and delay are reported. Comparison with state-of-the-art DA architectures for FPGA implementation provides an average of 64% reduction in area and 22% improvement in throughput. |
11,807 | Please write an abstract with title: Effective Implementation of Convolutional Long Short-Term Memory (ConvLSTM) Network in Forecasting Solar Irradiance, and key words: Support vector machines, Deep learning, Training data, Solar energy, Predictive models, Power system stability, Power grids. Abstract: Even though solar energy usage for power generation is currently gaining popularity in many nations of the world, its unpredictability is still posing a great challenge. This problem is mainly caused by the stochastic nature of radiative power responsible for solar energy use in electric power generation. In this paper, a Convolutional Long Short-Term Memory (ConvLSTM) network is introduced to predict solar irradiance on an hourly basis. Five-year historical weather information obtained from Johannesburg was utilized as the input dataset. Using 80% of the entire dataset, the model was trained up to 1,000 epochs until there was no significant improvement in its accuracy. The testing data were introduced to determine the effectiveness of the predictive model. To measure its accuracy, the Root Mean Square Error (RMSE) metric was used. The result obtained from this experiment was compared with the ones obtained using Support Vector Machine (SVM) and Extreme Gradient Boosting (XGB) models trained separately with the same amount of data. The performance indicators showed that the ConvLSTM model outperformed the XGB and SVM models with the nRMSE value of 1.62%. It is suggested that implementing ConvLSTM for solar power prediction in Johannesburg could ensure better control of the problems of cascading solar radiation on power grid connections. |
11,808 | Please write an abstract with title: An Access Control Model for Web Services in Business Process, and key words: Access control, Web services, Information security, Companies, Environmental economics, Protection, Software architecture, Computer science, Asia, Authorization. Abstract: Business process describes a set of services that span enterprise boundaries and are provided by enterprises that see each other as partners. Web services is widely accepted and adopted to construct business process. Web services are built in exposed environment and open to security threats. When a web service contained in a business process is authorized to illegal users, it will cause economic loss of the service provider. Although there exist some standards for security of Web services and access control for services in distributed systems are well studied, there is a lack of comprehensive approach in access control for web services, especially in business process. In this paper, an extended RBAC model, called WS-RBAC, is proposed to secure web services in business process. The model takes web services in business process as protected objects and extends the classical RBAC model. Next, The software architecture of WS-RABC is presented. This paper also presents how to specify business process in the model and the authorization constraints of WS-RBAC based on WS-Policy. |
11,809 | Please write an abstract with title: Reinforcement Learning based MIMO Controller for Virtual Inertia Control in Isolated Microgrids, and key words: Renewable energy sources, Simulation, Neural networks, Optimal control, Europe, Reinforcement learning, Microgrids. Abstract: In this paper, we propose a multi-input multi-output controller for optimal control of nonlinear energy storage, using deep reinforcement learning (DRL) algorithm. This controller provides the frequency support in an isolated microgrid with high penetration of variable renewable energy sources and varying system inertia. To achieve an optimal control we redesigned neural network of actor and critic, simplified deep deterministic policy gradient (DDPG) rules, and reorganized the reward/punishment system. Simulation results show the efficiency of the proposed virtual inertia control architecture in several scenarios. |
11,810 | Please write an abstract with title: Analysis of thermal noise spike cancellation, and key words: Noise cancellation, Magnetic heads, Magnetoresistance, Magnetic analysis, Magnetic materials, Voltage, Pulse amplifiers, Noise reduction, Solid modeling, Predictive models. Abstract: Thermally induced voltage pulses have been reported by Gorter et al. in the output of magneto-resistive reading heads. To reduce this thermal noise, Gorter et al. added a second magnetoresistive element on the same substrate but with a large head-to-tape distance. The outputs of these two stripes are differentially amplified to reject common mode noise. A theoretical analysis is made of the heat flow in magnetoresistive heads due to frictional heat generated at the head/tape interface. This model predicts that the dual stripe geometry will be effective for thermal noise cancellation only for low tape velocity or low thermal noise frequency and/or high thermal diffusivity substrate/cover material for the magnetoresistive elements. This result is also expected to be qualitatively valid for thermal noise due to intermittent cooling by the tape of Joule heat generated in the magneto-resistive elements. |
11,811 | Please write an abstract with title: DXICP: A Fast Registration Algorithm for Point Cloud, and key words: Point cloud compression, Shape, Urban areas, Feature extraction, Real-time systems, Iterative algorithms, Explosives. Abstract: The registration of point cloud is essentially to obtain a relatively accurate coordinate transformation matrix through operation. Generally speaking, the registration is to discover the position conversion matrix of the overlap between clouds. In this paper, a new algorithm DXICP is raised to handle the problem of low precision and slow time of traditional ICP. First, uniform downsampling is carried out after the input of the original point cloud. Then the 3D-SIFT algorithm is used to extract the feature points, and the FPFH algorithm is used to describe that. Finally, the RANSAC algorithm is used for rough registration, and then the optimized ICP is used for precise registration. The algorithm in this paper is proved to be better than the traditional ICP in both accuracy and speed. |
11,812 | Please write an abstract with title: Flux paths and flux transfer mechanism in the T joints of three phase transformer cores, and key words: Phase transformers, Transformer cores, Magnetic cores, Lamination, Magnetic flux, Density measurement, Coils, Geometry, Position measurement, Voltage. Abstract: A better understanding of flux behavior within specific regions of a transformer core can lead to improved core design and magnetic efficiency. Flux paths and the flux transfer mechanisms have been determined for two practical T joints of different designs employed in two similar three-phase three limbed transformer cores. Each core was energized at three different core flux densities. The instantaneous flux density patterns both parallel to and perpendicular to the rolling plane of the laminations are presented in graphical and vectorial forms for both types of T joints. By "freezing" the continually changing flux pattern within a T joint, it was possible to trace individual flux paths through the joint and to determine the basic flux transfer mechanism between adjacent laminations. Flux behavior within the joints shows that while its path is dependent on both T joint design and core flux density, the basic flux transfer mechanism remains unchanged in both T joints and at all core flux densities. |
11,813 | Please write an abstract with title: Routing restorable bandwidth guaranteed connections using maximum 2-route flows, and key words: Routing, Bandwidth, Optical fiber networks, Signal restoration, Optical receivers, Multiprotocol label switching, Aggregates, Interference, Image motion analysis, Educational institutions. Abstract: Routing with service restorability is very important in multiprotocol label switched (MPLS) networks, and is a necessity in optical networks. For restoration, each connection has an active path and a disjoint backup path. The backup path enables service restoration upon active path failure. For bandwidth efficiency, backups may be shared. This requires that at least the aggregate backup bandwidth used on each link be distributed to nodes performing route computations. If this information is not available, sharing is not possible. Also, one scheme in use for restorability in optical networks is for the sender to transmit simultaneously on the two disjoint paths and for the receiver to choose data from the path with stronger signal. This has the advantage of fast receiver-initiated recovery upon failure but it does not allow backup sharing. We consider the problem of efficient dynamic routing of restorable connections when backup sharing is not allowed. Our objective is to be able to route as many connections as possible for one-at-a-time arrivals and no knowledge of future arrivals. Since sharing cannot be used for achieving efficiency, the goal is to achieve efficiency by improved path selection. We show that by using the minimum-interference ideas used for non-restorable routing, we can develop efficient algorithms that outperform previously proposed algorithms for restorable routing such as routing with the min-hop like objective of finding two disjoint paths with minimum total hop-count. We present two new and efficient algorithms for restorable routing without sharing, and one of them requires only shortest path computations. We demonstrate that both algorithms perform very well in comparison to previously proposed algorithms. |
11,814 | Please write an abstract with title: Fault Tolerant Adders With Low Overheads For Smart Computing, and key words: Measurement, Fault tolerance, Event detection, Image processing, Fault tolerant systems, Machine learning, Electrical fault detection. Abstract: In this paper the authors analyse different adder designs with respect to the extent of fault. If the fault is localized the fault free part of the tree may be brought in use thereby improving the throughput. The results indicate the suitability of Ling parallel prefix adders for implementation of fault tolerant adders due to the fact that the fault effects the even or odd part of the tree and leaves the odd or even part fault free. A design for online error detection is proposed employing the Ling parallel prefix adders as the adjacent columns compute independently. Then the design is used in the implementation of the 15–4 compressor of a Wallace Tree Multiplier so that it has the capacity to detect faults. Further, a Ling parallel prefix adder with fault tolerance is designed to augment the online error detection design. This is compared with the existing designs and it shows an improvement in delay of about 30% compared to RCA-TMR scheme and 50% when compared to the traditional Prefix adders with fault tolerance. There is a significant improvement in ADP & PDP values. Finally, a scheme to mitigate overheads using approximate computation is proposed. |
11,815 | Please write an abstract with title: Overcomplete Representations Against Adversarial Videos, and key words: Deep learning, Additives, Target recognition, Conferences, Focusing, Network architecture, Robustness. Abstract: Adversarial robustness of deep neural networks is an extensively studied problem in the literature and various methods have been proposed to defend against adversarial images. However, only a handful of defense methods have been developed for defending against attacked videos. In this paper, we propose a novel Over-and-Under complete restoration network for Defending against adversarial videos (OUDefend). Most restoration networks adopt an encoder-decoder architecture that first shrinks spatial dimension then expands it back. This approach learns undercomplete representations, which have large receptive fields to collect global information but overlooks local details. On the other hand, overcomplete representations have opposite properties. Hence, OUDefend is designed to balance local and global features by learning those two representations. We attach OUDefend to target video recognition models as a feature restoration block and train the entire network end-to-end. Experimental results show that the defenses focusing on images may be ineffective to videos, while OUDefend enhances robustness against different types of adversarial videos, ranging from additive attacks, multiplicative attacks to physically realizable attacks. Code: https://git;hub.com/shaoyuanlo/OUDefend |
11,816 | Please write an abstract with title: Modified Dynamic Movement Primitives: Robot Trajectory Planning and Force Control Under Curved Surface Constraints, and key words: Trajectory, Robots, Task analysis, Force, Force control, Trajectory planning, Impedance. Abstract: Dynamic movement primitives (DMPs) have been widely applied in robot motion planning and control. However, in some special cases, original discrete DMP fails to generalize proper trajectories. Moreover, it is difficult to produce trajectories on the curved surface. To solve the above problems, a modified DMP method is proposed for robot control by adding the scaling factor and force coupling term. First, the adjusted cosine similarity is defined to assess the similarity of the generalized trajectory with respect to the demonstrated trajectory. By optimizing the similarity, the trajectories can be generated in all situations. Next, by adding the force coupling term derived from adaptive admittance control to the transformation system of the original DMP, the controller achieves the force control ability. Then, the modified DMP-based robot control system is developed. The stability and convergence of the system are proved. Finally, the high precisions of the proposed method are verified by simulations and experiments. The method is significant for trajectory learning and generalization on the curved surface. |
11,817 | Please write an abstract with title: Modeling of hard disk drives for vibration analysis using a flexible multibody dynamics formulation, and key words: Hard disks, Assembly systems, Iron, Speech analysis, Coils, Equations, Lagrangian functions, Finite element methods, Modal analysis, Electric shock. Abstract: This paper presents a flexible multibody dynamics formulation to analyze the vibration of hard disk drives. The formulation is applied in analyzing the vibration of the voice coil motor (VCM)-actuators assembly and the disks-spindle system. There are flexible components as well as rigid bodies in the system. Governing equations of motion of the VCM-actuators assembly and disks-spindle system are derived by using a Lagrangian formulation. Elastic deformations of flexible bodies are described by modal coordinates from a finite-element (FE) formulation. After obtaining the formulations, modal analysis and nonoperating shock response are analyzed. The numerical analyses are significantly faster compared to a full FE approach and is potentially useful when the system requires repeated analysis of the model of the entire system when certain design variables are changed. |
11,818 | Please write an abstract with title: Identity-Expression Ambiguity in 3D Morphable Face Models, and key words: Solid modeling, Three-dimensional displays, Image resolution, Shape, Gesture recognition, Rendering (computer graphics), Task analysis. Abstract: 3D Morphable Models are a class of generative models commonly used to model faces. They are typically applied to ill-posed problems such as 3D reconstruction from 2D data. Several ambiguities in this problem's image formation process have been studied explicitly. We demonstrate that nonorthogonality of the variation in identity and expression can cause identity-expression ambiguity in 3D Morphable Models, and that in practice expression and identity are far from orthogonal and can explain each other surprisingly well. Whilst previously reported ambiguities only arise in an inverse rendering setting, identity-expression ambiguity emerges in the 3D shape generation process itself. We demonstrate this effect with 3D shapes directly as well as through an inverse rendering task, and use two popular models built from high quality 3D scans as well as a model built from a large collection of 2D images and videos. We explore this issue's implications for inverse rendering and observe that it cannot be resolved by a purely statistical prior on identity and expression deformations. |
11,819 | Please write an abstract with title: Modified Co-doped ZnO nanostructures on SPCE for Xanthine detection in early food spoilage, and key words: Electrodes, Electric potential, Sensitivity, II-VI semiconductor materials, Electric variables measurement, Zinc oxide, Nanomaterials. Abstract: Co-doped ZnO nanostructures were fabricated using electrodeposition method on screen printed carbon electrodes. Physical properties of synthesized Co-doped ZnO nanomaterials were studied using EPMA and elemental analysis. The electrochemical analysis was studied using cyclic voltammetry for electrode evaluation and xanthine measurement. The results showed that Co-Zn nanostructures were uniformly deposited on SPCE. Modified electrodes demonstrated good repeatability and electrical performance, and applied for xanthine measurement. Xanthine can be quantified with our electrodes and presented a negative log-linear relationship. We believe that the developed electrode has great potential towards xanthine-sensitive biosensor for early meat spoilage detection. |
11,820 | Please write an abstract with title: A Case Study on the Practical Knowledge of Teaching: Creative Teacher of Preschool, and key words: Conferences, Education, Interviews, Artificial intelligence. Abstract: The purpose of this research is to explore the content of practical knowledge of the creative teaching for preschool teachers, and adopts the case study of qualitative research. Through purposive sampling, the participants were two preschool teachers who had won the Creative Teaching Award. The collection of interviews, observations and teaching logs, which are sorted, analyzed and summarized. The findings revealed that their self-knowledge presents creative personality traits and plays the role of teacher as a guide. They believed that the knowledge on educational goals was to promote the whole-person development of children as the focus. Their knowledge on learners includes children learning in play, children being curious individuals, and children's interests. Finally, the knowledge on the curriculum and teaching of the teachers includes thematic curriculum, guiding teaching strategies, and multiple assessment. |
11,821 | Please write an abstract with title: Real-time Smile Detection using Integrated ML Model, and key words: Machine learning algorithms, Social networking (online), Entertainment industry, Prototypes, Streaming media, Feature extraction, Real-time systems. Abstract: This study investigates the ways to provide unhindered entertainment solutions to artists and common people. The research has led to the conclusion that a new social media platform can be built for artists around the globe. The aim of the study is to merge video conferencing features with face detection and smile detection machine learning algorithms to provide an interactive environment to audience virtually over Internet. The findings of the study suggest that people from different age groups and places can find the comedy shows of common interests for enjoyment. The project can be launched as application to build a worldwide community of comedians. The paper is intended to provide a fast and efficient Machine learning model to detect smiling faces in real time environment with low latency and high accuracy. The comparison between some smile detection models is done among which our model has proven to be more effective than 2 pre-existing models with accuracy score of 91.97%. Although the accuracy of this model is less than other one having 94.87% accuracy. |
11,822 | Please write an abstract with title: A Distributed Algorithm for the Maximum Flow Problem, and key words: Distributed algorithms, Irrigation, Labeling, Heuristic algorithms, Fluid flow, Transportation, Mobile ad hoc networks, Books, Algorithm design and analysis, Bidirectional control. Abstract: This paper presents an asynchronous distributed algorithm for solving the maximum flow problem which is based on the preflow-push approach of Golberg-Tarjan. Each node in graph initially knows the capacities of outgoing and incoming adjacent arcs, the source nodes knows additionally the number of nodes in graph. Nodes execute the same algorithm, and exchange messages with neighbors until the maximum flow is established. The algorithm is applicable in cases of multiple sources and/or targets. We give also here some ideas to adjust our algorithm to dynamic changes of arc capacities. |
11,823 | Please write an abstract with title: Procrustean Training for Imbalanced Deep Learning, and key words: Training, Deep learning, Knowledge engineering, Computer vision, Neural networks, Fitting, Training data. Abstract: Neural networks trained with class-imbalanced data are known to perform poorly on minor classes of scarce training data. Several recent works attribute this to over-fitting to minor classes. In this paper, we provide a novel explanation of this issue. We found that a neural network tends to first under-fit the minor classes by classifying most of their data into the major classes in early training epochs. To correct these wrong predictions, the neural network then must focus on pushing features of minor class data across the decision boundaries between major and minor classes, leading to much larger gradients for features of minor classes. We argue that such an under-fitting phase over-emphasizes the competition between major and minor classes, hinders the neural network from learning the discriminative knowledge that can be generalized to test data, and eventually results in over-fitting. To address this issue, we propose a novel learning strategy to equalize the training progress across classes. We mix features of the major class data with those of other data in a mini-batch, intentionally weakening their features to prevent a neural network from fitting them first. We show that this strategy can largely balance the training accuracy and feature gradients across classes, effectively mitigating the under-fitting then over-fitting problem for minor class data. On several benchmark datasets, our approach achieves the state-of-the-art accuracy, especially for the challenging step-imbalanced cases. |
11,824 | Please write an abstract with title: A sampling technique for variance estimation of long-range dependent traffic, and key words: Sampling methods, Traffic control, Communication system traffic control, Internet, Predictive models, Demand forecasting, Algorithm design and analysis, Dynamic range, Gaussian noise, Maximum likelihood estimation. Abstract: Due to the long-range dependence of Internet traffic, the sampling distribution of the variance is very hard to obtain and, as a result, confidence intervals cannot be provided. Nevertheless, we show that the r-decimated variance sampling distribution can be approximated by a /spl chi//sup 2/ distribution. This sampling technique can be used to provide a confidence interval for the variance, with significant benefits for many applications in Internet dimensioning, traffic forecasting and control. |
11,825 | Please write an abstract with title: Effective Multiscale Residual Network With High-Order Feature Representation for Optical Remote Sensing Scene Classification, and key words: Optical sensors, Remote sensing, Feature extraction, Optical imaging, Convolution, Tensors, Optical fiber networks. Abstract: Scene classification of optical remote sensing is a basic but important task because of its broad application in a range of fields. Due to the powerful feature extraction capabilities, convolutional neural networks (CNNs) have been widely used in optical remote sensing scene classification tasks. Despite the remarkable efforts have been achieved, there are still several problems existed, including the effective multiscale feature description for complex scene, rotation, and low interclass diversity problems. In this letter, to address these mentioned problems and construct a powerful CNN for optical remote sensing scene classification, an effective multiscale residual network with a high-order feature representation (MRHNet) is proposed. First, data preprocessing is utilized to adapt the rotation invariance problem. Second, related to the original residual module, a pyramid convolution is introduced to realize the multiscale feature extraction, and then, its feature description ability is further improved by an effective channel attention module. Third, inspired by the tensor decomposition and its completion, a high-order feature representation structure is designed for recovering discriminative fine-scale details into deep layers to solve the low interclass diversity problem. Finally, extensive experiments are carried on two widely used scene classification datasets (e.g., AID and NWPU-RESISC45), and comparing results show that the proposed MRHNet can achieve superior performances. |
11,826 | Please write an abstract with title: Robotic Ultrasonography for Autonomous Non-Invasive Diagnosis—A Systematic Literature Review, and key words: Medical robotics, Ultrasonography, Autonomous systems, Ultrasonic imaging, Noninvasive treatment, Quality assessment. Abstract: This systematic review was conducted to synthesize and critically appraise the current evidence on the automation of non-invasive diagnostic ultrasonography using robots. Medline, Scopus, EMBASE, Web of Science, and PubMed databases were searched using a defined search strategy. Eighteen studies were included for consideration after reviewing 1,932 studies. Through appraisal, the selected studies were found to be of high quality. An automated ultrasound examination can be divided into two stages. The first stage involves localization of the region of interest and moving the probe close to that region, while the second stage involves manipulating the probe configuration around the region of interest to scan and acquire an optimized image. Although the second stage was fully automated in all the analyzed systems, the first initialization stage requires full or partial assistance from the sonographer in 11 of the systems. Future studies should propose novel methods to perform these procedures without the sonographer’s aid. Fourteen studies used a combination of visual and force feedback to control the scanning and optimization. The utilization of ultrasound image feedback for probe manipulation during this process has the potential to improve the accuracy and robustness of the system. |
11,827 | Please write an abstract with title: Comparison of 3D PET data bootstrap resampling methods for numerical observer studies, and key words: Positron emission tomography, Image reconstruction, Geometry, Solid modeling, Reconstruction algorithms, Background noise, Noise generators, Humans, Nuclear and plasma sciences, Scattering. Abstract: Bootstrap methods have been proposed to estimate the statistical properties of PET and SPECT images by generating multiple statistically equivalent data sets from few data samples. Bootstrap methods might be very helpful for detection performance studies, whose aim is to evaluate detectability based on large series of statistically equivalent images. However, previous reports regarding bootstrap approaches suggest different results. The goal of this work was to compare the accuracy of three bootstrap methods, namely the list-mode based method used by Dahlbom and the parametric and non-parametric sinogram-based methods proposed by Haynor and by Buvat respectively, for predicting the moments of order 1 and 2 (mean and variance) of reconstructed images in 3D PET. We used simulated data generated with the GATE simulation tool and compared the mean and variance images estimated from 100 repeated scans and from series of 100 bootstrap resampled data generated with the three bootstrap methods. Results indicate that the non-parametric bootstrap method by Buvat based on a small number of statistically equivalent data samples seems to correctly estimate the mean of reconstructed images unlike the other two methods based on one original scan only. The comparison of variance images also indicates significant discrepancies between the method by Buvat and the other two bootstrap methods. However, the variance image from the 100 repeated scans, which served as a gold standard, was too noisy to allow us to determine which bootstrap method was the most accurate. |
11,828 | Please write an abstract with title: Social integration and distance learning focused on hospitalized children with their habitual educational centers and leisure-pedagogical entertainment, and key words: Computer aided instruction, Pediatrics, Hospitals, Web and internet services, Educational technology, Computer science education, Electronic learning, Educational institutions, Collaborative work. Abstract: The continuous progressing of computing and communications, along with the increasing number of Internet users, lead us to update the concept of health services, being succeeded to offer new and revolutionary functionalities. Derived from this evolution, the supply of health attention services via this media is required from the state authorities and administrations. Internet, as a universal net, offers a wide diversity of mechanisms that enable these types of services, from the concept of bibliographic information or as medium, between users of public heath and health staff, or between patient that reside in hospitals and their external family-social environment. In this sense, most demanding areas are the newborn children and paediatrics services. The position of the children that temporarily reside in hospitals should be emphasized for being somehow excluded from their natural environment, and coexistence with their families and other children. This event can be efficiently surmountable with technologies that nowadays are used for other purposes. The inclusion of those services using Internet (e-Health) will serve the child during his stay in hospital offering services of social integration with their own teaching centres keeping contact with their habitual teachers and colleagues, or participating in games, chats, etc. defined by experts in child care. |
11,829 | Please write an abstract with title: ScatterWeb - Low Power Sensor Nodes and Energy Aware Routing, and key words: Scattering, Routing, Hardware, Embedded software, Energy conservation, Energy efficiency, Capacitors, Power generation, Solar power generation, Photovoltaic cells. Abstract: ScatterWeb, a distributed, heterogeneous platform for the ad-hoc deployment of sensor networks offers hardware together with open, fully documented software for the deployment of embedded sensor networks. Already low power by design, the sensor nodes offer additional energy conservation mechanisms and support energy efficient routing, such as, e.g., solar-aware routing. In order to enable a battery-free operation, the nodes implement permanent power sensing and start the transmission if and only if the energy stored in a capacitor is sufficient for the complete transmission plus the reception of an acknowledgement. Energy-aware routing takes the current incoming power of environmental energy sources into account. Depending on the current power generated by, e.g., solar cells, traffic is always forwarded by the nodes having sufficient power. Together with additional power saving, auto-configuration, and remote reprogramming techniques, these mechanisms enable ScatterWeb nodes to survive many years in real-life scenarios without any on-site maintenance. |
11,830 | Please write an abstract with title: Quantum annealing for ICT system design automation, and key words: Cloud computing, Annealing, Automation, Computer architecture, Generators, Hardware, System analysis and design. Abstract: In this paper, we propose a novel architecture for a (quasi) optimization problem solver for system designing automation that combines a problem generator and general problem solver. It efficiently generates the number of constraints from a simple description about system requirements, and solves the optimization problem at high speed by utilizing a powerful problem solver. Our challenge is to apply quantum annealing for this purpose. However, we faced the following technical problems caused by the fundamental properties of a quantum annealer: P1) a quantum annealer does not accept a constraint with inequality, which is necessary to describe system design problems, and P2) digit overflow of the coefficient value in the constraints. In this paper, we illustrate the overall architecture of our problem solver and clarify the aforementioned issues. Then, we present solutions to each problem: S1) a conversion method from inequality to equation by the augmented Lagrange method, and S2) a problem conversion method that reduces the number of digits of the coefficient without changing the meaning of the problem. Through experiments with a number of example problems, we evaluated the performance and accuracy of our scheme in comparison with a traditional rigorous problem solver. We show that our scheme outperforms the solver at least in a number of situations, and discuss its future utility. |
11,831 | Please write an abstract with title: Synthesis of Run-To-Completion Controllers for Discrete Event Systems, and key words: Control systems, Discrete-event systems, Floods, Standards. Abstract: A controller for a Discrete Event System must achieve its goals despite its environment being capable of resolving race conditions between controlled and uncontrolled events. Assuming that the controller loses all races is sometimes unrealistic. In many cases, a realistic assumption is that the controller sometimes wins races and is fast enough to perform multiple actions without being interrupted. However, in order to model this scenario using control of DES requires introducing foreign assumptions about scheduling, that are hard to figure out correctly. We propose a more balanced control problem, named run-to-completion (RTC), to alleviate this issue. RTC naturally supports an execution assumption in which both the controller and the environment are guaranteed to initiate and perform sequences of actions, without flooding or delaying each other indefinitely. We consider control of DES in the context where specifications are given in the form of linear temporal logic. We formalize the RTC control problem and show how it can be reduced to a standard control problem. |
11,832 | Please write an abstract with title: Analyzing the impact of process variations on DRAM testing using border resistance traces, and key words: DRAM chips, Integrated circuit testing. Abstract: As a result of variations in the fabrication process, different memory components are produced with different operational characteristics, a situation that complicates the fault analysis process of manufactured memories. This paper discusses the issue of process variations, and shows how to deal with it in the context of fault analysis and test generation. The paper also introduces the concept of border resistance traces as a tool to optimize test stresses and inspect the impact of process variations on the optimization procedure. The concepts are discussed in the paper with the help of a practical example of a specific defect in the memory. |
11,833 | Please write an abstract with title: A Nanophotonic Broadband Quantum Optical Frequency Comb, and key words: Lithium niobate, Optical resonators, Bandwidth, Lasers and electrooptics, Laser modes, Optical harmonic generation, Broadband communication. Abstract: We demonstrate generation of a broadband quantum optical frequency comb using spontaneous parametric down-conversion in a dispersion-engineered thin-film lithium niobate resonator spanning 30-THz bandwidth and 600 comb lines at 50-GHz mode spacing. |
11,834 | Please write an abstract with title: A project management support tool using communication for agile software development, and key words: Project management, Programming, Scattering, Software development management, Quality control, Quality management, Educational institutions, Software tools, Open source software, Accidents. Abstract: Recently, agile software development methods are popular because software should be developed in a short period. However, conventional project management techniques are often not adaptable to such new development methodologies. Especially, progress and quality control of the document-based management does not fit the agile software development. Therefore, a new project management support tool has been developed based on a new communication model. The new model focuses on relationships between communication and project states. The basic idea of the model is that good communication leads to high quality products and good progress of projects. Based on scattering ratio of communication on time series, the tool can calculate project state as a whole. From results of trial experiments, we confirmed that the strong correlation coefficient between the scattering ratios of communication and the product qualities. Furthermore, the tool was applied to open source projects. The projects' features were clarified in communication analysis using the tool. |
11,835 | Please write an abstract with title: Hierarchical deterministic image watermarking via polynomial interpolation, and key words: Watermarking, Polynomials, Interpolation, Image reconstruction, Steganography, Discrete cosine transforms, Communications technology, Mathematics, Degradation, Image processing. Abstract: This paper presents a novel method for steganographic image watermarking with two main innovative features: i) it involves a hierarchical control, committing the watermark reconstruction to a trusted layered authority; and ii) it is deterministic, embedding a short meaningful signature into the cover image. Experimental results show that the embedded signature can be accurately recovered even in presence of a reasonable amount of image degradation due to image processing operators, such as filtering, geometric distorsions and compression. |
11,836 | Please write an abstract with title: Tiler: An Autonomous Region-Based Scheme for SMR Storage, and key words: Cleaning, Writing, Computer science, Magnetic recording, Memory management, Resource management, Time factors. Abstract: Shingled Magnetic Recording (SMR) Disks are adopted as a high-density, non-volatile media that significantly precedes conventional disks in both the storage capacity and cost. However, inefficient read-modify-writes (RMWs) greatly challenge the management of SMR disks. This article for the first time presents an approach called Tiler to manage SMR disks by dividing the physical space into small autonomous regions (ARs). Each AR can manage its space allocation, address mapping, and cleaning independently. By managing these ARs in a log-structured way, RMWs can be avoided; besides, ARs can also help update data when the adjacent tracks contain no valid data. Tiler is capable of partitioning a large-scale cleaning into self-contained-small-scale cleaning and thus, the data that need to be relocated are limited inside independent ARs, which further minimizes the performance overhead. Our experimental results show that Tiler can shorten the overall system response time by 50.21 percent and reduce the cleaning time by 90.24 percent on average. |
11,837 | Please write an abstract with title: Robot Interaction Studio: A Platform for Unsupervised HRI, and key words: Heating systems, Visualization, Automation, Conferences, Medical treatment, Human-robot interaction, Color. Abstract: Robots hold great potential for supporting exercise and physical therapy, but such systems are often cumbersome to set up and require expert supervision. We aim to solve these concerns by combining Captury Live, a real-time markerless motion-capture system, with a Rethink Robotics Baxter Research Robot to create the Robot Interaction Studio. We evaluated this platform for unsupervised human-robot interaction (HRI) through a 75-minute-long user study with seven adults who were given minimal instructions and no feedback about their actions. The robot used sounds, facial expressions, facial colors, head motions, and arm motions to sequentially present three categories of cues in randomized order while constantly rotating its face screen to look at the user. Analysis of the captured user motions shows that the cue type significantly affected the distance subjects traveled and the amount of time they spent within the robot’s reachable workspace, in alignment with the design of the cues. Heat map visualizations of the recorded user hand positions confirm that users tended to mimic the robot’s arm poses. Despite some initial frustration, taking part in this study did not significantly change user opinions of the robot. We reflect on the advantages of the proposed approach to unsupervised HRI as well as the limitations and possible future extensions of our system. |
11,838 | Please write an abstract with title: Data-Aided Doppler Compensation for High-Speed Railway Communications Over mmWave Bands, and key words: Antenna arrays, Channel models, Channel estimation, Doppler effect, Millimeter wave technology, Wireless communication. Abstract: Millimeter wave communications show great potentials in many applications, one of which is the high-speed railway(HSR) communication system. However, a major challenge is the Doppler effect caused by the relative-movement between the train and the base station (BS), which leads to fast channel variation. To compensate for the Doppler shift, an accurate channel model is indispensable, and the far-field channel model is generally employed, which assumes that the dimensions of the antenna arrays are negligible compared to the distance between transmitter and receiver. This model is widely used in Cellular systems, but the underlining assumption is not always true for railway communication systems. In this paper, the modeling of the Doppler effect for millimeter wave in HSR communications is conducted, and data-aided Doppler estimation and compensation algorithms are designed based on the new model. We show that the conventional far-field channel model is based on the first-order Taylor expansion of the actually channel, and the second-order component cannot be ignored for HSR communications. Extensive simulations are conducted to verify the validity of the new model and the effectiveness of the proposed algorithms. |
11,839 | Please write an abstract with title: An overview of the modern light dimmer: design, operation, and application, and key words: Power semiconductor switches, Brightness, Thyristors, Semiconductor devices, Power electronics, Switching circuits, Lighting control, Fixtures, Power generation, Electronics industry. Abstract: The light dimmer is a specialized circuit that utilizes switching techniques to control the brightness of a light fixture. Thyristors (unidirectional semiconductor device) and triacs (bidirectional semiconductor device) are the basic power electronic devices used to control the switching. Once the current crosses the zero-crossing of AC power, the brightness is determined. The sine wave is cut in accordance to the zero-crossing to determine the output power. The light dimmer is an efficient and practical application of power electronic devices in an industrial or consumer product. |
11,840 | Please write an abstract with title: Automatic Drainage Pipeline Defect Detection Method Using Handcrafted and Network Features, and key words: defect detection, image restoration, image segmentation, hybrid features. Abstract: Effective maintenance of urban drainage pipeline networks is critical to the healthy development of cities. Routine CCTV surveys are costly, time-consuming and rely on technicians. In this paper, we propose a method to detect pipeline defects automatically, which can improve the efficiency of pipeline maintenance and save cost and reduce dependence on technicians. We use image restoration method to remove the interference of ropes in the pipeline image, before using Canny edge detection operator to extract the texture information of the defects. Then look for contours regionally to identify suspected defect areas. We combine the hybrid LBP handcrafted and VGG network features of suspected defect areas and use SVM classifier to predict pipeline defects. This method is more than 90% accurate on the test set. Furthermore, the high efficiency of this method enables it to compete with the performance of trained technicians. In general, this method of automatically detection pipeline defects provides a new option for the Urban Drainage Group and has a good development prospect. |
11,841 | Please write an abstract with title: Impact of Thread and Frequency Scaling on Performance and Energy Efficiency: An Evaluation of Core i7-8700K Using SPEC CPU2017, and key words: Benchmark testing, Energy efficiency, Clocks, C++ languages, Frequency measurement, Energy measurement. Abstract: This paper describes the results of measurement based studies focusing on performance and energy efficiency of SPEC CPU2017 speed and rate benchmark runs on the Intel's Core i7-S700K processor. We measure execution time and the total energy consumed during individual benchmark runs with 1 thread/copy (IT/IC) and 6 threads/copies (6T/6C) when the processor clock is set to its nominal frequency of 3.7 GHz. Next, we evaluate how changes in the processor clock frequency impact performance, energy efficiency, as well as a composite metric called PE that captures both performance and energy efficiency. We find that IT/IC benchmark runs at the nominal frequency achieve an optimal PE, whereas 6T/6C benchmark runs achieve optimal PE when running at 2.7 GHz. |
11,842 | Please write an abstract with title: Note on a Class of Codes Introduced by Séguin, Allard, and Bhargava, and key words: Decoding, Geometry, Galois fields, Error correction codes, Protection, Communications Society, Parity check codes, Linear code, Error correction. Abstract: In this correspondence, we apply a theorem in finite geometry to obtain an improvement of the codes recently introduced by Séguin, Allard, and Bhargava to provide error protection for data in the ASCII format. Our construction yields a fast decoding algorithm. |
11,843 | Please write an abstract with title: A Hybrid Continuous Time Incremental and SAR Two-Step ADC with 90.5dB DR over 1MHz BW, and key words: Performance evaluation, Power demand, Switches, Data processing, Switched capacitor circuits, Real-time systems, Solid state circuits. Abstract: The sensors in real-time data processing IoT devices require high resolution and sub-MHz data converters. They are often implemented as Incremental ADCs (IADCs) [1], [2] because of their efficient oversampling technique and low latency. In discrete-time incremental ADCs (DT-IADC) [2], the nonlinearity and charge injection of the sampling switch degrades the performance, and power hungry opamps are needed to provide fast and accurate settling for the switched capacitor circuits. These limitations may prevent the use of DT-IADCs in high resolution and wide bandwidth (BW) applications. Continuous-time incremental ADCs (CT-IADC) overcome these issues by removing the sampling switches, and CT integrators allow relaxed specifications for the opamps settling accuracy to save power. Hence, CT-IADCs enable higher resolution, faster conversion speed with lower power consumption. |
11,844 | Please write an abstract with title: Radiative transfer in the near field, and key words: Phonons, Electromagnetic surface waves. Abstract: Summary form only given. The behaviour of systems that are supposed to be very well-known may reveal surprises when we look at them on a nanometric length scale. This is the case of light emission by a body at temperature T. A thermal source such as a blackbody or the incandescent filament of a light bulb is often presented as the typical example of an incoherent source as opposed to a laser. Indeed, whereas a laser is monochromatic and very directional, a thermal source has a broad spectrum and is usually quasi-isotropic. However, it has been shown recently that the field emitted by a thermal source made of a polar material at a distance of the order of 10 to 100 nm is enhanced by more than four orders of magnitude and is partially coherent. The purpose of this paper is to discuss the implications of these effects for the radiative heat transfer between objects separated by distances in the range of the nanometer. |
11,845 | Please write an abstract with title: A Sliced Wasserstein Loss for Neural Texture Synthesis, and key words: Training, Neural networks, Computer architecture, Production, Tools, Feature extraction, Complexity theory. Abstract: We address the problem of computing a textural loss based on the statistics extracted from the feature activations of a convolutional neural network optimized for object recognition (e.g. VGG-19). The underlying mathematical problem is the measure of the distance between two distributions in feature space. The Gram-matrix loss is the ubiquitous approximation for this problem but it is subject to several shortcomings. Our goal is to promote the Sliced Wasserstein Distance as a replacement for it. It is theoretically proven, practical, simple to implement, and achieves results that are visually superior for texture synthesis by optimization or training generative neural networks. |
11,846 | Please write an abstract with title: Excitation-collection dual resonance of quantum dot in micropillar cavity, and key words: Quantum dot lasers, Optical device fabrication, Quantum dots, Optical imaging, Optical pumping, Pump lasers, Photonics. Abstract: We have investigated the cavity-resonant excitation of quantum dot which is spectrally and spatially coupled with the fundamental mode of micropillar, achieving a single photon source that is highly efficient both in excitation and emission. © 2020 The Author(s). |
11,847 | Please write an abstract with title: Open Challenges in Synthetic Speech Detection, and key words: Technical requirements, Forensics, Collaboration, Training data, Solids, Regulation, Recording. Abstract: In this paper the current status and open challenges of synthetic speech detection are addressed. The work comprises an initial analysis of available open datasets and of existing detection methods, a description of the requirements for new research datasets compliant with regulations and better representing real-case scenarios, and a discussion of the desired characteristics of future trustworthy detection methods in terms of both functional and non-functional requirements. Compared to other works, based on specific detection solutions or presenting single dataset of synthetic speeches, our paper is meant to orient future state-of-the-art research in the domain, to quickly lessen the current gap between synthesis and detection approaches. |
11,848 | Please write an abstract with title: Developing Dataset of Response Variance for Automatic English Speaking Testing App, and key words: speech recognition, testing English speaking, dataset, job interview simulation. Abstract: Through student speeches and other means, English teachers have already been able to assess their students' speaking skills firsthand. A huge number of pupils' speaking skills must be evaluated, which takes time. Thus, the need for an automated methodology to gauge English-speaking proficiency. It is good to examine English speaking with a computer using speech recognition technologies. However, to accurately assess the students' speaking performance automatically using computer requires a large dataset of students' various responses that are marked as appropriate responses. These responses are further marked as correct or expected responses, which later be used for automatic scoring generation and other various useful features. In this research we develop a dataset by collecting, analysing, categorising, and weighting various answer possibilities collected from students' responses to specific questions. The dataset, from 20 participants, was examined through Confusion Matrix, and it yielded accuracy score above 80%. However, this yielding result needs further testing with higher number of participants to get stronger accuracy. This dataset is expected to power the automatic English speaking testing app in assessing students' speaking performance. Eventually, the app is expected to be helpful for English teachers to efficiently score the speaking performance of huge numbers of students. |
11,849 | Please write an abstract with title: Research on the Relationship between China’s Import and Export Trade and Confidence Index–Dynamic Analysis based on VAR Model, and key words: Reactive power, Analytical models, Correlation, Government, Psychology, Production, Market research. Abstract: With the deepening of globalization, changes in China's import and export trade will affect consumers' plans for saving and consumption in the future, thus affecting China's development strategy of internal circulation. In order to explore the influence relationship between China's import and export trade and consumer confidence, VAR model is built to conduct empirical analysis on the relationship between total import, total export and consumer confidence index. Moreover, the short-term dynamic change relationship between variables is further explored through impulse response function and variance decomposition analysis. The empirical results show that there is a certain degree of correlation between China's import and export trade and confidence index. To be specific, in the early stage, the change of trade import and export will have a negative impact on consumer confidence, while the impact of consumer confidence index on trade export volume has a lag. Therefore, the Chinese government should continue to pay attention to the development of the real economy and guide and encourage the real enterprises to realize the optimization and upgrading of industrial structure. The government should also actively guide consumers to consume healthily so as to accelerate the construction of the new development pattern of “double cycle”. |
11,850 | Please write an abstract with title: Signal-To-Noise Ratios in Bandpass Deadzone Limiters, and key words: Signal to noise ratio, Frequency modulation, Noise level, Gaussian noise, Demodulation, Narrowband, Detectors, Marine animals, Time series analysis, Frequency locked loops. Abstract: The solution for signal-to-noise ratio at the output of a deadzone-limiter narrow-band-filter combination when the input is a sine wave plus narrow-band Gaussian noise is presented. Expressions are derived for output signal and noise power as functions of input signal-to-noise ratio, signal-to-deadzone ratio, and noise-to-deadzone ratio. The resulting output signal-to-noise ratios are plotted for the various cases. |
11,851 | Please write an abstract with title: Multi-Well Avalanche Selenium Detector for Time-of-Flight PET, and key words: Selenium, Detectors, Photonics, Electrodes, Photodetectors, Optical device fabrication, Scintillators. Abstract: For the first time, we propose using amorphous selenium (a-Se) as the photoconductive material for time-of-flight (TOF) PET detectors. One major drawback of a-Se is its poor timing jitter stemming from low carrier mobility due to shallow-traps, a problem that must be circumvented for TOF applications. Thus, we propose using a nanopattern multi-well selenium detector that enables both avalanche multiplication gain and ultrafast charge sensing in one device. We've previously shown the capabilities of our avalanche mode multi-well selenium detector, which has a large active area, impact ionization avalanche gain and timing jitter on the order of 100 ps. Using Cramér-Rao Lower Bound analysis in conjunction with experimental measurements, we calculate the lower bound on coincidence time resolution for our selenium photodetector and compare it with that of the current state-of-the-art TOF-PET photodetectors. Our results show that our multi-well selenium detector is a promising candidate to achieve 100 ps coincidence time resolution in TOF-PET using standard-sized scintillator crystals with a photodetector that is cost-effective and uniformly scalable to large area. |
11,852 | Please write an abstract with title: Intercarrier interference suppression and channel estimation for OFDM systems in time-varying frequency-selective fading channels, and key words: Interference suppression, Channel estimation, OFDM, Time varying systems, Frequency-selective fading channels, Frequency domain analysis, Computational complexity, Time domain analysis, Demodulation, Parameter estimation. Abstract: In orthogonal frequency division multiplexing (OFDM) systems, channel variations within an OFDM block destroy orthogonality between subcarriers, resulting in intercarrier interference (ICl), which increases an error floor in proportional to normalized Doppler frequency. To mitigate the effects of channel variations, many schemes have been proposed, but they are computationally complex or at the price of sacrificing spectral efficiency. In this paper, we first provide an ICI analysis in both time- and frequency-domain while existing literatures analyze the ICI effects mainly in the frequency domain. Based on this analysis, we then propose a novel ICI suppression technique, which uses iterative ICI cancellation in time domain and has a computational complexity that is linear in the OFDM symbol length. Channel estimation in rapidly time-varying scenarios is critical for ICl suppression and coherent demodulation. We also propose a scheme for estimating the channel parameters varying within an OFDM block. Along with the channel estimation scheme, we investigate the issue of optimum pilot tone placement. Theoretical analysis and simulation results show that the proposed ICl suppression method and channel estimation scheme have low computational complexity and good performance for most Doppler frequency of practical importance. |
11,853 | Please write an abstract with title: Losses Computation in Thin Conductive Sheaths of Power Cables via an Integral Approach, and key words: Cable shielding, Geometry, Integral equations, Finite element analysis, Computational modeling, Power cables, Conductors. Abstract: A thin-shell integral equation formulation is applied to the computation of eddy-current losses in submarine ac cables. The continuous helical symmetry of the geometry is exploited for reducing the computational cost of the simulation. |
11,854 | Please write an abstract with title: Development and Tests of a 220 kV Novel Composite Insulator with Lightning Protection and Icing Flashover Prevention, and key words: Air gaps, Lightning, Zinc oxide, Varistors, Flashover, II-VI semiconductor materials, Insulators. Abstract: Metal-oxide surge arresters and anti-icing insulators are widely used in transmission lines to prevent lightning and icing flashover, respectively. However, these two technologies have the disadvantage of single function, and sometimes surge arresters could be difficult to install because of their structural size mismatch with the tower cross arms. In this study, a 220 kV novel composite insulator with lightning protection and icing flashover prevention (CI/LP&IFP) is developed. By experimental research, the air gap distance between grading rings are obtained, the specification and number of zinc oxide (ZnO) varistors, the creepage distance and the sheds configuration of the 220 kV CI/LP&IFP are designed. Lighting and switching impulse discharge characteristics, and icing flashover characteristics are studied using experimental methods to validate the lightning protection and icing prevention performance. Test results indicate that, the designed air gap distance of 880±10 mm can ensure that the 220 kV CI/LP&IFP is discharged under a lightning over-voltage of more than 900 kV and would not be discharged under switching and power frequency overvoltages. When the icing thickness is 12.8 mm, the icing flashover voltage gradient of the 220 kV CI/LP&IFP is 14.57% more than that of the 220 kV conventional composite insulators. Results in this study can give help to the flashover performances improvement of transmission lines in heavy lightning and icing regions. |
11,855 | Please write an abstract with title: Research on public safety emergency management of “Smart city”, and key words: Smart cities, Safety management, Production, Big Data, Emergency services, Real-time systems, Information management. Abstract: All aspects of the construction of the smart city need to rely on the information management platforms to achieve sustainable expansion and intelligent integration. It also needs to rely on the information model to obtain reliable big data onto real-time sharing, so as to improve the efficiency of urban governance of multiple dimensions. The construction and application of emergency big data and intelligent security emergency management platform will help to improve emergency management efficiency and reduce losses caused by emergencies. This paper expounds the problems existing on the emergency management of public safety problems with the smart city, uses research methods such as data analysis, is committed to the collection, processing and analysis of big data of the emergency management system, scientifically forecasts the public emergency management needs of the smart city, and puts forward suggestions to improve the public safety emergency management in combination with the concept of the smart city. |
11,856 | Please write an abstract with title: Research of pattern matching in intrusion detection, and key words: Pattern matching, Intrusion detection, Protocols, Buildings, Pattern analysis, Tree data structures, Information security, Information systems, Learning automata, Mathematics. Abstract: This paper studies the method of pattern matching in intrusion detection, analyzes the fault and lack of the current methods and proposes a trinary-tree-based automaton method, which avoids some lacks resulting from the changing of the node amount in traditional tree structure. In addition, during matching this method jumps some letters with unsuccessful information, so it obtains higher speed. |
11,857 | Please write an abstract with title: Semantic-based retrieval of remote sensing images in a grid environment, and key words: Image retrieval, Remote sensing, Ontologies, Sun, Geographic Information Systems, Prototypes, Satellites, Information retrieval, Content based retrieval, Time measurement. Abstract: Because of the surprisingly increasing volume and complicated nature of remote sensing images (RSIs), one of the main obstacles to realize efficient retrieval of the RSIs is the lack of effective sharing technologies and semantic description methods. In this letter, we design and implement a prototype grid system named RSIsGrid for semantic-based RSIs retrieval using ontology and grid technologies. In order to verify the semantic-based method, measures such as the recall, precision, and query time are used. Test results have indicated that the semantic-based method can promote the query performance of the RSIs. |
11,858 | Please write an abstract with title: Sensor based on arrays of sub-micrometer scale resonant silicon cantilevers integrated monolithically with CMOS circuitry, and key words: Sensor arrays, Resonance, Silicon, RLC circuits, Driver circuits, Chemical and biological sensors, Integrated circuit measurements, Biosensors, Voltage, Resonant frequency. Abstract: A mass sensor, based on arrays of cantilevers for multiple detection, is presented. Excitation and readout is performed electrostatically. Polysilicon cantilevers are integrated monolithically with CMOS in a compatible process. Integration of arrays of cantilever allows performing multiple detections on the same device. A multiplexing system to select individual cantilevers is implemented as well as a scheme based on two readout circuits for differential measurements. A mass resolution of 5/spl middot/10/sup -18/ g has been achieved in the first working devices. |
11,859 | Please write an abstract with title: Ensemble Monte Carlo/molecular dynamics simulation of inversion layer mobility in Si MOSFETs - effects of substrate impurity, and key words: Monte Carlo methods, MOSFETs, Electromagnetic compatibility, Electron mobility, Substrates, Impurities, Particle scattering, Information systems, FETs, Threshold voltage. Abstract: Electron transport in bulk Si and MOSFET inversion layers is studied using an ensemble Monte Carlo (EMC) technique coupled with the molecular dynamics (MD) method. The Coulomb interactions among point charges (electrons and negative ions) are directly taken into account in the simulation. It is demonstrated that the static screening of Coulomb interactions is correctly simulated by the EMC/MD method. Furthermore, we calculate the inversion layer mobility in Si MOSFETs, and mobility roll-off near the threshold voltage is observed by the present approach. |
11,860 | Please write an abstract with title: Generating Cancellable Fingerprint Template Using Local-Similar Image, and key words: Image color analysis, Databases, Conferences, Machine learning, Fingerprint recognition, Security. Abstract: Fingerprint template is considered as a promising solution to solve the problem of fingerprint revocation, also is an indispensable key technology in the field of identification. In this context, a novel fingerprint template based on local-similar image (LSIT) is proposed. The generation of the LSIT mainly consists of two parts: replacing and hiding the original minutiae through expansion; mapping and abstracting fingerprint features according to the constructed local-similar image. On this basis, a cancellable fingerprint template characterized by color features transformed from minutiae can be obtained. The security and cancellability of the proposed LSIT are analyzed and discussed, and the recognition performance is experimented using the FVC2002 and FVC2004 databases. The experimental results indicate that the LSIT has promising performances, which provide a new way for fingerprint protection and application. |
11,861 | Please write an abstract with title: Fast Single-Cut Antenna Characterization by Near Field Measurements, and key words: Antenna measurements, Numerical analysis, Inverse problems, Europe, Noise measurement, Velocity measurement, Antennas. Abstract: A new approach for the partial reconstruction in near-field antenna characterization is presented. The goal of the partial reconstruction is to determine the optimal near-field sampling distribution required to provide a partial reconstruction of the antenna patter (along some cuts). The method is based on the formulation of the near-field characterization as a linear inverse problem and on the singular-value-optimization. It is aimed to reconstruct only that part of the unknown contributing to the far-field pattern along the desired cuts. A numerical analysis shows the performance of the method. |
11,862 | Please write an abstract with title: JAL MITRA Water Quality Monitoring and Reporting Using IoT, Cloud & Analytics, and key words: Earth, Degradation, Cloud computing, Water quality, Lakes, Rivers, Internet of Things. Abstract: Water is a key ingredient to life on earth. It is important to monitor and control the quality of water. As part of this study, an automated water quality monitoring and alerting system was envisaged. We propose a tripod solution to this problem in the form of an integrated system of Water Quality Monitoring and Reporting. It uses capabilities of internet of things, cloud and analytics. An IoT based platform collects vital water quality parameters and connects to cloud. The cloud-based analytics engine was used to monitor and perform analytics. Both these are integrated in the form of a web application referred in this paper as “Jal-Mitra”- a water friend. This helps to perform a root-cause analysis of water quality degradation at a sensor-deployed location and provide automatic recommendations. Such a system can be deployed in a large area such as lake, river and aquaculture for continuous water quality monitoring. |
11,863 | Please write an abstract with title: Hardware/Software Obfuscation against Timing Side-channel Attack on a GPU, and key words: Graphics processing units, Timing, Encryption, Correlation, Instruction sets, Side-channel attacks, Computer architecture. Abstract: GPUs are increasingly being used in security applications, especially for accelerating encryption/decryption. While GPUs are an attractive platform in terms of performance, the security of these devices raises a number of concerns. One vulnerability is the data-dependent timing information, which can be exploited by adversary to recover the encryption key. Memory system features are frequently exploited since they create detectable timing variations. In this paper, our attack model is a coalescing attack, which leverages a critical GPU microarchitectural feature the coalescing unit. As multiple concurrent GPU memory requests can refer to the same cache block, the coalescing unit collapses them into a single memory transaction. The access time of an encryption kernel is dependent on the number of transactions. Correlation between a guessed key value and the associated timing samples can be exploited to recover the secret key. In this paper, a series of hardware/software countermeasures are proposed to obfuscate the memory timing side channel, making the GPU more resilient without impacting performance. Our hardware-based approach attempts to randomize the width of the coalescing unit to lower the signal-to-noise ratio. We present a hierarchical Miss Status Holding Register (MSHR) design that can merge transactions across different warps. This feature boosts performance, while, at the same time, secures the execution. We also present a software-based approach to permute the organization of critical data structures, significantly changing the coalescing behavior and introducing a high degree of randomness. Equipped with our new protections, the effort to launch a successful attack is increased up to $1433X\times 178X$, while also improving encryption/decryption performance up to 7%. |
11,864 | Please write an abstract with title: Reconfigurable Multi-Mode Sigma Delta Modulator for 5G Applications, and key words: Sigma-delta modulation, 5G mobile communication, Software packages, Simulation, Modulation, Transfer functions, Bandwidth. Abstract: This paper presents a system level design of a reconfigurable multi-mode continuous-time low-pass sigma delta modulator for 5G applications. The proposed modulator can support multiple channel bandwidths in the 5G standard which are 80, 40, 20, and 10 MHz. The proposed modulator can be reconfigured easily for each channel bandwidth so that it can achieve the optimum performance in each mode. Moreover, the proposed modulator has a signal transfer function with a very slight peaking. The system level design and Simulink simulation results of the proposed modulator are presented. Furthermore, a circuit behavioral model that includes most of the circuit non-idealities is implemented and simulated in Cadence environment. The results show that the signal to noise and distortion ratio is 75.2 dB, 76.6 dB, 76.7 dB, and 77.6 dB for the channel bandwidths 80, 40, 20, and 10 MHz respectively. |
11,865 | Please write an abstract with title: Surface change of polyamide nanocomposite caused by partial discharges, and key words: Surface discharges, Partial discharges, Degradation, Electrodes, Atomic force microscopy, Scanning electron microscopy, Rough surfaces, Surface roughness, Polymers, IEC. Abstract: We have investigated partial discharge (PD) degradation for conventional polyamide-6. without nanoscale fillers (nanofillers) and polyamide-6 nanocomposites with 2 weight (wt) %, 4 wt% and 5 wt% addition. Such materials were subjected to partial discharge under the IEC (b) electrode configuration for evaluation. Comparisons were made as to the surface roughness observed by scanning electron microscopy and atomic force microscopy. It was found that the change in the surface roughness was far smaller in specimens with nanofillers than those without nanofillers, and that the 2 wt% addition was sufficient for improvement. This result indicates that polyamide-6 nanocomposite is more resistive to PDs than polyamide-6 without nanofillers. |
11,866 | Please write an abstract with title: Visual sonar: fast obstacle avoidance using monocular vision, and key words: Robot sensing systems, Robot vision systems, Sonar detection, Mobile robots, Object detection, Infrared sensors, Cameras, Image sensors, Sensor systems, Image segmentation. Abstract: We contribute a fast system for avoiding unknown obstacles on a mobile robot using a simple camera as the only sensor. The vision module detects objects, both known and unknown, around the robot. Unknown objects are detected by paying attention to occlusions of a floor of known colors. Range and angle to the objects is calculated and used to create a radial model of the vicinity of the robot. This modeling component keeps tracks of objects that are currently outside the field of view of the camera allowing the robot to avoid obstacles it is not currently looking at. We show the effectiveness of the vision and modeling algorithms by creating a simple behavior which wanders around while avoiding obstacles. |
11,867 | Please write an abstract with title: Direct observation of vacancy defects in electroplated Cu films, and key words: Annealing, Scattering parameters, Temperature, Grain boundaries, Grain size, Electron emission, Plastic films, Crystals, Parameter estimation, Positrons. Abstract: Vacant defects in electroplated Cu films are investigated by positron annihilation and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The evolution of vacancies was divided into two regions with respect to the annealing temperature. For temperature below 300/spl deg/C, the behavior of vacancies was closely related to grain growth. When the annealing temperature was over 300/spl deg/C, the vacancy concentration was estimated to be of the order of 10/sup 19/ /spl sim/10/sup 20//cm/sup 3/, which is similar to void volume estimates in stress induced voiding (SIV) failure. |
11,868 | Please write an abstract with title: SODA: a New Synthesis Infrastructure for Agile Hardware Design of Machine Learning Accelerators, and key words: Synthesizers, Hardware, Optimization, Task analysis, Tools, Libraries, Computer architecture. Abstract: Next-generation systems, such as edge devices, will have to provide efficient processing of machine learning (ML) algorithms, along with several metrics, including energy, performance, area, and latency. However, the quickly evolving field of ML makes it extremely difficult to generate accelerators able to support a wide variety of algorithms. Simultaneously, designing accelerators in hardware description languages (HDLs) by hand is laborious and time-consuming, and does not allow quick exploration of the design space. This paper discusses the SODA synthesizer, an automated open-source high-level ML framework-to-Verilog compiler targeting ML Application-Specific Integrated Circuits (ASICs) chiplets based on the LLVM infrastructure. The SODA synthesizers will allow implementing optimal designs by combining templated and fully tunable IPs and macros, and fully custom components generated through high-level synthesis. All these components will be provided through an extendable resource library, characterized by commercial and open-source logic design flows. Through a closed-loop design space exploration engine, developers will quickly explore their hardware designs along different dimensions. |
11,869 | Please write an abstract with title: Infrared Small Target Tracking via Gaussian Curvature-Based Compressive Convolution Feature Extraction, and key words: Target tracking, Feature extraction, Support vector machines, Convolution, Clutter, Visualization, Training. Abstract: The precision of infrared (IR) small target tracking is seriously limited due to lack of texture information and interference of background clutter. The key issue of robust tracking is to exploit generic feature representations of IR small targets under different types of background. In this letter, we present a new IR small target tracking method via compressive convolution feature (CCF) extraction. First, a Gaussian curvature-based feature map is calculated to suppress clutters so that the contrast between target and background can be obviously improved. Then, a three-layer compressive convolutional network, which consists of a simple layer, a compressive layer, and a complex layer, is designed to represent each candidate target by a CCF vector. Based on the proposed mechanism of feature extraction, a support vector machine (SVM) classifier with continuous probabilistic output is trained to compute the likelihood probability of each candidate. Finally, the long-term tracking for IR small target is implemented under the framework of the inverse sparse representation-based particle filter. Both qualitative and quantitative experiments based on real IR sequences verify that our method can achieve more satisfactory performances in terms of precision and robustness compared with other typical visual trackers. |
11,870 | Please write an abstract with title: A new PCI card for readout in high energy physics experiments, and key words: Field programmable gate arrays, Bridges, Hardware, Detectors, Mesons, Data acquisition, IEC standards, Silicon, Physics, Logic. Abstract: Recently, some high energy physics experiments have started to adopt readout systems based on the PCI architecture. In this context, a new PCI card that can be adapted to several readout schemes has been designed. It contains a 64-MiB local buffer, programmable FPGA logic, a hardware PCI bridge, and can be connected to mezzanine cards. The card is presently used in the NA60 experiment at the CERN SPS for the readout of several detectors. The interfacing to the different front-ends is provided by the mezzanine cards while the readout protocols are implemented in the FPGA. Moreover, it is used as a test readout system for the ALICE experiment muon chambers. This paper describes the card, with particular emphasis on its flexibility and relatively simple development, related to the use of an external PCI bridge. |
11,871 | Please write an abstract with title: Cage solitons of the Haus Master Equation, and key words: Additives, Shape, Chirp, Laser mode locking, Partial differential equations, Frequency-domain analysis, Europe. Abstract: Laser mode-locking is traditionally explained in the framework of the Haus Master Equation [1] . Eigensolutions of this partial differential equation propagate without changing their shape on time scales long compared to the cavity roundtrip, that is, these solutions are fundamental solitons of the equation. While there are several different solved Master Equations, the fast saturable absorber variant [1] is probably the most universal, describing Kerr-lens, additive pulse, and nonlinear polarization mode-locking. Chirped hyperbolic secants are known as the fundamental solitons of this Equation and were initially found to describe experimental findings very well. This agreement was challenged by the advent of few-cycle lasers, which showed deviating pulse shapes that rather seemed to agree with unexplainable sinc-like or Bessel-like functional shapes. Here we discuss a generalization of the Haus formalism [2] , solving the Master Equation as a set of coupled ordinary differential equations entirely in the frequency domain. From this differential equation, an algebraic discriminant can be derived that allows determining the complete set of fundamental solitons of this equation. These solitons agree very well with the experimentally reported few-cycle pulse shapes and the corresponding concave spectra. These solutions result whenever the mode-locked laser spectrum starts to encompass the entire available gain bandwidth, which acts like a spectral cage. Consequently, we termed these solutions "cage solitons." |
11,872 | Please write an abstract with title: MaxEnt Dreamer: Maximum Entropy Reinforcement Learning with World Model, and key words: Learning systems, Neural networks, Reinforcement learning, Entropy, Task analysis. Abstract: Model-based reinforcement learning algorithms can alleviate the low sample efficiency problem compared with modelfree methods for control tasks. However, the learned policy's performance often lags behind the best model-free algorithms since its weak exploration ability. Existing model-based reinforcement learning algorithms learn policy by interacting with the learned world model and then use the learned policy to guide a new round of world model learning. Due to weak policy exploration ability, the learned world model has a large bias. As a result, it fails to learn the globally optimal policy on such a world model. This paper improves the learned world model by maximizing both the reward and the corresponding policy entropy in the framework of maximum entropy reinforcement learning. The effectiveness of applying the maximum entropy approach to model-based reinforcement learning is supported by the better performance of our algorithm on several complex mujoco and deepmind control suite tasks. |
11,873 | Please write an abstract with title: The design of planar and rolled fat monopole antenna for UWB radio system, and key words: Ultra wideband antennas, Antenna measurements, Loss measurement, Dielectric substrates, Dielectric constant, Feeds, Impedance matching, Azimuth, Ultra wideband technology, Communications technology. Abstract: In this paper, we proposed two types of antennas, planar fat monopole antenna and rolled fat monopole antenna for UWB system. The rolled fat monopole antenna is designed to reduce the size of the planar fat monopole antenna and two antennas are compared. The proposed antennas have the omni-directional pattern in azimuth. They satisfy 3.1 GHz/spl sim/7.8 band GHz for VSWR <2, using the tapered radiator and partial ground plane. |
11,874 | Please write an abstract with title: Exploit Camera Raw Data for Video Super- Resolution via Hidden Markov Model Inference, and key words: Cameras, Image color analysis, Superresolution, Motion estimation, Image reconstruction, Hidden Markov models, Correlation. Abstract: To the best of our knowledge, the existing deep-learning-based Video Super-Resolution (VSR) methods exclusively make use of videos produced by the Image Signal Processor (ISP) of the camera system as inputs. Such methods are 1) inherently suboptimal due to information loss incurred by non-invertible operations in ISP, and 2) inconsistent with the real imaging pipeline where VSR in fact serves as a pre-processing unit of ISP. To address this issue, we propose a new VSR method that can directly exploit camera sensor data, accompanied by a carefully built Raw Video Dataset (RawVD) for training, validation, and testing. This method consists of a Successive Deep Inference (SDI) module and a reconstruction module, among others. The SDI module is designed according to the architectural principle suggested by a canonical decomposition result for Hidden Markov Model (HMM) inference; it estimates the target high-resolution frame by repeatedly performing pairwise feature fusion using deformable convolutions. The reconstruction module, built with elaborately designed Attention-based Residual Dense Blocks (ARDBs), serves the purpose of 1) refining the fused feature and 2) learning the color information needed to generate a spatial-specific transformation for accurate color correction. Extensive experiments demonstrate that owing to the informativeness of the camera raw data, the effectiveness of the network architecture, and the separation of super-resolution and color correction processes, the proposed method achieves superior VSR results compared to the state-of-the-art and can be adapted to any specific camera-ISP. Code and dataset are available at https://github.com/proteus1991/RawVSR. |
11,875 | Please write an abstract with title: Load Management in Active Distribution Network Including Stochastic Behaviour of DGs, and key words: Photovoltaic systems, Reactive power, Communication systems, Distribution networks, Load management, Generators, Wind turbines. Abstract: Distribution network advancement is the most trending topic in the power system. From reserve capacity reduction by distributed generator (DG) integration to consumer active participation for load management, all the significant changes are occurring in the distribution network. This paper proposes a consumer participation-based load management approach in presence of DGs. Distributed generators such as Photovoltaic (PV) and wind turbines are added to the distribution feeder in constant power voltage mode. Load management is proposed by providing monetary benefits to the consumer for their active participation. Excessive load shifting and formulation of the new peak is prevented by constraints such as thermal, voltage, active and reactive power limit of feeder. Special attention is paid to DGs reactive power supply. The performance of the proposed load management scheme is verified on 15-bus feeder system. |
11,876 | Please write an abstract with title: Windfarm Transient Support Analysis Considering the Different Wind Power Penetration Levels, and key words: Renewable energy sources, Codes, Wind energy, Stability criteria, Wind farms, Wind power generation, Power system stability. Abstract: The wind generation installation meets a remarkable increase in a decade in order to realize the carbon dioxide emission reduction. However, the high penetration of wind energy into the power system brings many operating challenges to the power system. Traditional system operating codes ask the generations to provide necessary support on the system frequency and voltage during the contingency. With the increased integration of wind energy into the system, some new codes are enacted to ask the wind power producer to participate in the system emergency regulation. However, the different penetration levels influence of wind energy on the system regulation have not received too much attention in the existing codes. In this paper, a code study of the wind farm transient support is conducted considering the different wind power penetration levels, in addition, some suggestions for the wind farm transient support codes are proposed. From the three control periods: wind generation participation moment, wind generation exit moment, and system fault recovery support by wind generation, the transient support capability of the wind generation under different penetration levels is studied. The case study conducted by a detailed wind farm model built in EMTDC/PSCAD provides simulation verifications to provide a guide for wind farm operators to make appropriate transient support control strategies. |
11,877 | Please write an abstract with title: Image Search With Text Feedback by Visiolinguistic Attention Learning, and key words: Visualization, Semantics, Task analysis, Feature extraction, Image representation, Linguistics. Abstract: Image search with text feedback has promising impacts in various real-world applications, such as e-commerce and internet search. Given a reference image and text feedback from user, the goal is to retrieve images that not only resemble the input image, but also change certain aspects in accordance with the given text. This is a challenging task as it requires the synergistic understanding of both image and text. In this work, we tackle this task by a novel Visiolin-guistic Attention Learning (VAL) framework. Specifically, we propose a composite transformer that can be seamlessly plugged in a CNN to selectively preserve and transform the visual features conditioned on language semantics. By inserting multiple composite transformers at varying depths, VAL is incentive to encapsulate the multi-granular visiolinguistic information, thus yielding an expressive representation for effective image search. We conduct comprehensive evaluation on three datasets: Fashion200k, Shoes and FashionIQ. Extensive experiments show our model exceeds existing approaches on all datasets, demonstrating consistent superiority in coping with various text feedbacks, including attribute-like and natural language descriptions. |
11,878 | Please write an abstract with title: Downstream VDSL channel tracking using limited feedback for crosstalk precompensated schemes, and key words: Feedback, Crosstalk, Bandwidth, Optical transmitters, Channel estimation, Amplitude estimation, Bit rate, DSL, Circuits, Algorithm design and analysis. Abstract: With increasing bandwidths and decreasing loop lengths, crosstalk becomes the main impairment in VDSL systems. For downstream communication, crosstalk precompensation techniques have been designed to cope with this issue by using the collocation of the transmitters. These techniques naturally need an accurate estimation of the crosstalk channel impulse responses. We investigate the issue of tracking these channels. Due to the lack of coordination between the receivers, and because the amplitude levels of the remaining crosstalk channels after precompensation are very low, blind estimation schemes are inefficient in this case. So some part of the upstream or downstream bit rate needs to be used to help the estimation. In this paper, we design a new algorithm to try to limit the bandwidth used for the estimation purpose by exploiting the collocation at the transmitter side. The principle is to use feedback from the receiver to the transmitter instead of using pilots in the downstream signal. It is shown by simulations that the proposed estimation is more efficient, in terms of needed overhead, than a classical scheme using pilot symbols. |
11,879 | Please write an abstract with title: Rate control by partial differential equation modeling, and key words: Partial differential equations, MPEG 4 Standard, Temperature, Video sequences, Streaming media, Process control, Electronic mail, Video coding, Video compression, Control systems. Abstract: This work presents a novel rate-control model. Based on the famous heat conduction equation (HCE), a rate transmission equation (RTE) is proposed to describe the bit-rate behaviors during video coding. RTE is inherently the famous diffusion equation. A new rate-control model is derived from the special solution to RTE. Based on this model, a new rate-control scheme is proposed for MPEG-4 applications. Experiments show that the proposed scheme achieves a better buffer status and higher picture quality over the MPEG-4 Q2 scheme. |
11,880 | Please write an abstract with title: Hardware-Software System for Monitoring Parameters of Magnetic Field Converters, and key words: Magnetic field measurement, Sensitivity, Conferences, Magnetic hysteresis, Software, Magnetic fields, Software measurement. Abstract: A mockup of the hardware-software system for monitoring accuracy parameters of magnetic field converters, such as a conversion characteristic, sensitivity, nonlinearity, hysteresis, trigger threshold, and others, has been developed. The calculated value of irregularity of magnetic field of the developed system is 0.5 - 0.6%. The maximum value of generated field magnetic induction is ± 58 mT. The increase and decrease of magnetic field magnitude is produced in minimal increments of 0.4 mT. The scheme of operation of the system, the software and the measurement process are observed. |
11,881 | Please write an abstract with title: Characterizing Multiple Patterns of Motor Intent Using Spatial-Temporal Information for Intuitively Active Motor Training in Stroke Survivors, and key words: Training, Decoding, AWGN, Rehabilitation robotics, Neuromuscular, Feature extraction. Abstract: Upper extremity motor function loss severely affects stroke survivors during daily life activities. Different rehabilitation robotic systems have been developed to allow stroke survivors regain their motor function. Meanwhile, most of the robots only operate in a passive mode and restrict the users to navigate predefined trajectories which may not align with their motion intent, thus limiting motor recovery. One way to resolve this issue would be to utilize a decoded movement intent to trigger intuitively active motor training for patients. In this direction, this study proposed and investigated the use of spatial-temporal neuromuscular descriptor (STD) for optimal decoding of multiple patterns of movement intents in patient to provide inputs for active motor training in the rehabilitation robotic systems. The STD performance was validated using High-Density surface electromyogram recordings from five stroke survivors who performed 21 limb movements. Experimental results show that the STD achieved a significant reduction in limb movement classification error (13.36%) even in the presence of the inevitable White Gaussian Noise compared to other methods (p<; 0.05). The STD also showed obvious class separability for individual movement. Findings from this study suggest that the STD may provide potential inputs for intuitively active motor training in stroke rehabilitation robotic systems.Clinical Relevance- This study showed that spatial-temporal neuromuscular information could aid adequate decoding of movement intents upon which intuitively active motor training could be achieved in stroke rehabilitation robotic systems. |
11,882 | Please write an abstract with title: Strategies for setting electric vehicle charging service fees considering user psychology, and key words: Analytical models, Costs, Roads, Psychology, Transportation, Pricing, Games. Abstract: To increase the average revenue of charging stations and reduce the travel cost of electric vehicle (EV) users, this paper proposes a strategy for setting charging service fees based on the psychology of EV users. Firstly, through the real-time traffic flow of urban traffic network, the flow-impedance model between traffic network nodes is constructed, the driving time of each road section of the road network is calculated; secondly, the charging station selection model based on regret theory is proposed by considering the driving and charging time and charging service fee of EV users; finally, the Hotelling model is introduced to analyze the distribution characteristics of charging demand influenced by charging service fee and develop The pricing scheme of charging service fee for target charging stations is formulated. Taking the 24-node traffic network of Sioux Falls as an example, simulation analysis verifies the rationality and effectiveness of the proposed strategy. |
11,883 | Please write an abstract with title: SVM Model based Computerized Bone Cancer Detection, and key words: Cancer, Bones, Image segmentation, Filtering, Support vector machines, Magnetic resonance imaging, Neural networks. Abstract: Among the many types of cancers, bone cancer is one with which most of the deaths occur in the world. Around 10000 deaths are occurring in a year in India due to bone cancer. Bone cancer is the most dangerous and deaths can be avoided if it is detected in the early stage. Here, an automatic bone cancer detection system is proposed to aid the oncologists in early detection of bone cancers and helps them to undergo a timely treatment. Support Vector Machine (SVM) based M3 filtered and Fuzzy C-Means (FCM) segmentation method is proposed to detect the bone cancers. An accuracy of about 92% is achieved with the proposed method. |
11,884 | Please write an abstract with title: Analysis on Vacuum Type On-load Tap-Changer about Abnormal Increase of Acetylene Content in Oil Chromatography, and key words: Resistance, Switches, Oil insulation, Oils, Electrical resistance measurement, Power transformer insulation, Switching circuits. Abstract: Taking an abnormal increase of acetylene content in oil chromatogram of 220kV transformer vacuum type on-load tap-changer as an example, the diagnosis method is introduced. In the case of no abnormality found in conventional DC resistance, voltage ratio and DC compound switching waveform test, the diverter switch of on-load tap-changer is inspected by hanging core. The full step switching waveform is acquired by DC power supply and oscilloscope, the abnormal situation of voltage waveform is analyzed, and the defect location is accurately judged by combining the disassembly inspection and the principle of switching steps. The results show that the interior resistance chip of the transition resistance has poor contact, overheating and low-energy discharge during the switching process cause the cracking of insulating oil to produce acetylene. |
11,885 | Please write an abstract with title: A Survey on Masked Facial Detection Methods and Datasets for Fighting Against COVID-19, and key words: Face detection, COVID-19, Artificial intelligence, Faces, Detectors, Neural networks, Monitoring. Abstract: Coronavirus disease 2019 (COVID-19) continues to pose a great challenge to the world since its outbreak. To fight against the disease, a series of artificial intelligence (AI) techniques are developed and applied to real-world scenarios such as safety monitoring, disease diagnosis, infection risk assessment, and lesion segmentation of COVID-19 CT scans. The coronavirus epidemics have forced people wear masks to counteract the transmission of virus, which also brings difficulties to monitor large groups of people wearing masks. In this article, we primarily focus on the AI techniques of masked facial detection and related datasets. We survey the recent advances, beginning with the descriptions of masked facial detection datasets. A total of 13 available datasets are described and discussed in detail. Then, the methods are roughly categorized into two classes: conventional methods and neural network-based methods. The conventional methods are usually trained by boosting algorithms with hand-crafted features, which accounts for a small proportion. Neural network-based methods are further classified as three parts according to the number of processing stages. Representative algorithms are described in detail, coupled with some typical techniques that are described briefly. Finally, we summarize the recent benchmarking results, give the discussions on the limitations of datasets and methods, and expand future research directions. To our knowledge, this is the first survey about masked facial detection methods and datasets. Hopefully our survey could provide some help to fight against epidemics. |
11,886 | Please write an abstract with title: Multimedia Intervention and Big Data Analysis Framework of English Online Guiding Connection under the Internet Background, and key words: Education, Big Data, Internet, Data mining, Media, Data models, Conferences. Abstract: Multimedia intervention and the big data analysis framework of the English online guiding connection under the Internet background is designed in this paper. Novelties are focused on two aspects. (1) In the multimedia player, users can add one or more media files to the playlist. The program traverses all the added files, checks the legality of each file, and then saves all valid media sources in the media source queue, this is used to optimize the structure. (2) In the multimedia player, users can add one or more media files to the playlist. The program traverses all the added files, checks the legality of each file, and then saves all valid media sources in the media source queue. The novel system is designed for assistance tasks. The experiment compared with the latest models have proven well performance. |
11,887 | Please write an abstract with title: Induction Motor Parameters Identification in Noisy Environment, and key words: Industrial electronics, Induction motors, Parameter estimation, Simulation, Velocity control, Measurement uncertainty, Rotors. Abstract: Squirrel cage induction motors are widely used in the industrial field as they present many advantages compared to other types of electric machines. They are self-starting, need little maintenance, can work in harsh environment and are relatively cheap. Many industrial applications requiring current or speed control of the machine need the knowledge of the machine parameters. Therefore, induction motor parameter identification algorithms are developed taking in consideration the accuracy of the identification process which impacts on the quality of the control and thereby the overall system. These algorithms are usually sensitive to measurement noise thus there usage in noisy industrial environment is not desirable. This paper presents three induction motor offline identification algorithms and test their accuracy and their ability to work in noisy environment. The first method subject to the study is a Least Mean Square (LMS) based identification method working at standstill, the second is a newly introduced method robust toward noises and the third is the classic no-load and blocked rotor identification method. Simulation results are presented and finally conclusions are drawn. |
11,888 | Please write an abstract with title: A Techno-Economic Investigation on Hydrogen Utilization as a Long-term Energy Storage Solution for Microgrids, and key words: Renewable energy sources, Electric potential, Hydrogen, Microgrids, Developing countries, Security, Reliability. Abstract: The study aims to demonstrate a standalone PV-Hydrogen-battery microgrid's technical and economic merits in a developing country. Besides having adequate renewable energy resources, necessary fossil fuel resources have also been deployed in the microgrid to create a reliable and sustainable system. The primary renewable energy resource explored is the solar PV system. The diesel-powered generators are integrated to support the system stability in high PV penetration scenarios. In such cases, energy storage options are also integrated to store excess electricity, provide sufficient autonomy, system stability and virtual inertia. Despite the higher initial cost, Li-ion based batteries and Hydrogen have received widespread acceptance as potential renewable energy storage technologies for coping with the variability nature of renewable energy resources. In this study, a microgrid is designed for a remote site in Bangladesh, and the system is optimized using seasonal load and real-time market data from Bangladesh. The results indicate that Hydrogen may be used as a long-term energy storage solution even in a developing country and thus, a diesel-PV-Hydrogen-battery microgrid has been found to be efficient and cost-effective for remote Bangladeshi communities. |
11,889 | Please write an abstract with title: Rate-compatible punctured convolutionally (RCPC) space-frequency bit-interleaved coded modulation (SF-BICM), and key words: Convolutional codes, Interleaved codes, Modulation coding, Silicon carbide, OFDM modulation, Wireless LAN, Transceivers, Interference cancellation, MIMO, Transmitting antennas. Abstract: This paper proposes a low-complexity space-frequency bit-interleaved coded modulation (SF-BICM) transceiver with successive interference cancelling (SIC) processing for multiinput multioutput (MIMO) orthogonal frequency division multiplexing (OFDM) system. Two schemes are presented in order to improve the detection performance of SF-BICM perturbated by the error propagation at SIC receiver. First, the bit stream to each transmit antenna is distributed via the rate-compatible puncturing (RCP) such that the SIC process is "code-assisted". Second, a simple heuristic soft bit-metric computation is proposed to compensate for the incorrect soft information caused by the error propagation. Simulation results in the indoor wireless local area network (WLAN) channels show that the proposed RCPC SF-BICM with the new soft bit-metric has significant power gains up to 6dB over the conventional SIC receiver. |
11,890 | Please write an abstract with title: New proposed structural design and manufacturing tolerances for HF log-periodic dipole arrays, and key words: Impedance, Strain, Antenna radiation patterns, Resonant frequency, Dipole antennas, Market research, Couplings. Abstract: Stringent guidelines are usually followed for structural design and manufacturing tolerances of HF log-periodic dipole arrays. When such antennas are manufactured on site, and/or erected in isolated areas with unskilled labour, these tolerances can easily be exceeded. This paper reports on a study which indicates that the accepted tolerance guidelines can be relaxed significantly, without detrimentally affecting the antenna's gain, radiation pattern or input impedance. |
11,891 | Please write an abstract with title: A new substrate for realizing hemispherical encapsulant layer to enhance light efficiency of light-emitting diodes, and key words: Substrates, Light emitting diodes, Coatings, Viscosity, Phosphors, Potential energy. Abstract: Nowadays, light-emitting diodes (LEDs) have been widely applied in many light occasions. Encapsulant layer is of essential important to the light efficiency of LEDs. In this study, a new LED substrate with a outspread encapsulant coating area was designed for realizing hemispherical encapsulant layer. The fluid manipulation ability of the new substrate was investigated by numerical simulations based on the volume of fluid method, and the light efficiency enhancement of LED with the new substrate was verified by experiments. The simulated results show that compared to the conventional LED substrate, the new substrate holds ~ 3 times the volume of encapsulant without flow over the coating area, so it realizes hemispherical encapsulant layer easier. The experimental results show that compared to the flat encapsulant layer, the hemispherical encapsulant layer realized by the new substrate increases the light efficiency by ~75% for the blue LED. We think this new substrate would be of great help to the development of LED packaging. |
11,892 | Please write an abstract with title: Demonstration of Overlay Dynamic Spectrum Access Based on SMSE Framework, and key words: dynamic spectrum access, overlay, SMSE, cognitive radio. Abstract: Cognitive radio (CR) and dynamic spectrum access (DSA) are the effective ways to solve the spectrum congestion problem. Three kinds of basic DSA approaches are respectively dynamic exclusive use, open sharing and hierarchical access. The hierarchical access model is perhaps the most compatible with solving the current spectrum congestion problem. So, in this paper, we will set up an overlay DSA system which is an effective approach of the hierarchical access model. Firstly, we make use of the spectrally modulated spectrally encoded (SMSE) framework to generate OFDM waveforms for the secondary user (SU) which can be considered as the overlay waveform. Then we use the signal which is generated by the walkie-talkie to access the overlay DSA system as a primary user (PU) or an interference signal. The universal software radio peripheral (USRP) and spectrum analyzer are used to generate and analyze the power spectrum density (PSD) of the coexistence of a SU and a PU or an interference signal. The experimental result demonstrates that the overlay DSA system can achieve the function of turning off the sub-carriers corresponding to the frequency of the PU. It also shows that the system can greatly improve the efficiency of the spectrum utilization due to dynamically allocate the spectrum. |
11,893 | Please write an abstract with title: Wind Speed Data Repairing Method Based on Bidirectional Prediction, and key words: Wind speed, Distributed databases, Predictive models, Maintenance engineering, Wind power generation, Data models, Wind forecasting. Abstract: In order to repair the lost data in distributed wind power system, this paper puts forward a wind speed data repairing model based on a new bidirectional prediction method. This model consists of two one-way prediction models. In each prediction model, the original wind speed data are decomposed into several intrinsic mode functions (IMFs) and a residue signal by ensemble empirical mode decomposition (EEMD) method. Then the Savitzky-Golay (SG) filter is used to reduce noise for high-frequency IMFs. Next the long short-term memory (LSTM) model and autoregressive integrated moving average (ARIMA) model are combined to predict low-frequency IMFs and the noise reduction results respectively. At the end, all those forecast results are added and form a one-way result. By weighted average of two one -way results, the repairing result is calculated. The experimental results from multiple prediction cases show that this method can get more accurate results. |
11,894 | Please write an abstract with title: Parameter-Based Testing and Debugging of Autonomous Driving Systems, and key words: Costs, Conferences, Debugging, Cost function, Software, Test pattern generators, Autonomous vehicles. Abstract: Testing of Autonomous Driving Systems (ADSs) is of paramount importance. However, ADS testing raises several challenges specific to the domain. Typical testing (coverage criteria, test generation, and oracle definition) and debugging activities performed for software programs are not directly applicable to ADSs, because of the lack of proper test oracles, and the difficulty of specifying the desired, correct ADS behavior. We tackle these challenges by extending and combining existing approaches to the domain of testing ADS. The approach is demonstrated on an industrial path planner. The path planner decides which path to follow through a cost function that uses parameters to assign a cost to the driving characteristics (e.g., lateral acceleration or speed) that must be applied in the path. These parameters implicitly describe the behavior of the ADS. We exploit this idea for defining a coverage criterion, for automatically specifying an oracle, and for debugging the path planner. |
11,895 | Please write an abstract with title: A Novel Ground Fault Detection Method for Electric Vehicle Powertrains Based on a Grounding Resistor Voltage Analysis, and key words: Grounding, Resistors, Circuit faults, Batteries, Inverters, Voltage measurement, Fault currents. Abstract: The growing adoption of electric vehicles has recently attracted increasing attention of scientists and brought about pioneering research studies from various fields. Safety concerns particularly those regarding ground faults detection and protection, have extensively been addressed. Ground faults occur quite frequently in electric vehicles and they may be due to severe operation conditions, such as vibrations, twists or even crashes. Generally, the first ground fault is not dangerous, since the powertrain systems, namely, the dc bus where the batteries are connected, the power inverter and one or more ac machines, are generally ungrounded. The second ground fault, however, can produce malfunction in some systems, power loss or even serious damages. Locating the fault has often proved hard and time consuming. For this reason, the present study focuses on developing a ground-fault detection method for electric vehicles capable of determining on which side, the dc or the ac, the ground fault is located. The method is based on the analysis of the voltage in a grounding resistor connected between the midpoint of the battery pack and ground. Based on the polarity and harmonics, it is possible to locate the ground fault. This method has been verified excellent results have been achieved using computer simulations and experimental tests in a 140-kW electronic power inverter fed by a 480 Vdc battery. |
11,896 | Please write an abstract with title: Generate Test Data from C/C++ Source Code using Weighted CFG and Boundary Values, and key words: Knowledge engineering, Tools, Systems engineering and theory, Flow graphs, Testing. Abstract: This paper presents two test data automatic generation methods which are based on weighted control flow graph (named WCFT) and boundary values of input parameters (named BVTG). Firstly, WCFT method generates a CFG from a given unit function, updates weight for it, then generates test data from the greatest weight test paths. In the meantime, WCFT can And dead code that can be used for automatic source code errors fix. Secondly, BVTG method generates test data from boundary values of input parameters of the given unit function. The combination of the two generated test data sets from these two methods will improve the error detection ability while maintaining a high code coverage. An implemented tool (named WCFT4Cpp) and experimental results are also presented to show the effectiveness of the two proposed methods in both time required to generate test data and error detection ability. |
11,897 | Please write an abstract with title: Design Development and Engineering Analysis of the Recording Device Unit from the System for Receiving and Converting Information, and key words: Wireless communication, Space vehicles, Wireless sensor networks, Heat engines, Switches, Thermal analysis, Remote sensing. Abstract: The storage unit of the system for receiving and converting information for a promising spacecraft has been discussed. The components of this unit, which are power modules, control module, information switching cell, and secondary power supply cell have been described. The design of a special frame from the composition of a storage unit was considered, which serves to install internal and other components in it, ensuring their protection and support of the normal operation. This frame made it possible to provide a wireless connection between power cells and other cells, which together gave the minimum weight and dimensions of the unit. Special attention was paid to the strength and thermal analysis of the block structure. The results of the engineering analysis made it possible to choose the optimal design solutions that ensured the stable operation of the unit and efficient heat removal from the heat-loaded components. |
11,898 | Please write an abstract with title: Dataless Model Selection With the Deep Frame Potential, and key words: Dictionaries, Sparse representation, Robustness, Coherence, Neural networks, Computer architecture, Machine learning. Abstract: Choosing a deep neural network architecture is a fundamental problem in applications that require balancing performance and parameter efficiency. Standard approaches rely on ad-hoc engineering or computationally expensive validation on a specific dataset. We instead attempt to quantify networks by their intrinsic capacity for unique and robust representations, enabling efficient architecture comparisons without requiring any data. Building upon theoretical connections between deep learning and sparse approximation, we propose the deep frame potential: a measure of coherence that is approximately related to representation stability but has minimizers that depend only on network structure. This provides a framework for jointly quantifying the contributions of architectural hyper-parameters such as depth, width, and skip connections. We validate its use as a criterion for model selection and demonstrate correlation with generalization error on a variety of common residual and densely connected network architectures. |
11,899 | Please write an abstract with title: Localization of a Nano-transmitter in a Diffusive MC System with Multiple Fully-absorbing Receivers, and key words: Location awareness, Pervasive computing, Transmitters, Conferences, Telemedicine, Estimation, Receivers. Abstract: This paper presents new results about localization of a pointwise transmitter in a molecular communication (MC) diffusive channel by means of a spherical array whose elements are fully-absorbing (FA) receivers. The performance of two different spherical arrays is analyzed to estimate the position of the transmitter that differ in the configuration of the FA receivers on their surface. The proposed localization method relies on a model that has been recently developed to predict the temporal asymptotic cumulative number of molecules absorbed by each of the FA receivers. The approach first estimates the distances between the transmitter and the FA receivers and then use them in a multilateration technique. One of the most promising applications of localization in telemedicine is targeted-drug delivery, which is realized by means of nano-robots. Numerical results are used to demonstrate the accuracy of the proposed method. |
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