Journal of Zhejiang University-Science C-Computers & Electronics最新文献_第2页

A VHDL application for kinematic equation solutions of multi-degree-of-freedom systems 多自由度系统运动方程解的VHDL应用

Journal of Zhejiang University-Science C-Computers & Electronics Pub Date : 2014-12-01 DOI: 10.1631/jzus.C1400120

Hüseyin Oktay Erkol, H. Demirel

{"title":"A VHDL application for kinematic equation solutions of multi-degree-of-freedom systems","authors":"Hüseyin Oktay Erkol, H. Demirel","doi":"10.1631/jzus.C1400120","DOIUrl":"https://doi.org/10.1631/jzus.C1400120","url":null,"abstract":"As kinematic calculations are complicated, it takes a long time and is difficult to get the desired accurate result with a single processor in real-time motion control of multi-degree-of-freedom (MDOF) systems. Another calculation unit is needed, especially with the increase in the degree of freedom. The main central processing unit (CPU) has additional loads because of numerous motion elements which move independently from each other and their closed-loop controls. The system designed is also complicated because there are many parts and cabling. This paper presents the design and implementation of a hardware that will provide solutions to these problems. It is realized using the Very High Speed Integrated Circuit Hardware Description Language (VHDL) and field-programmable gate array (FPGA). This hardware is designed for a six-legged robot and has been working with servo motors controlled via the serial port. The hardware on FPGA calculates the required joint angles for the feet positions received from the serial port and sends the calculated angels to the servo motors via the serial port. This hardware has a co-processor for the calculation of kinematic equations and can be used together with the equipment that would reduce the electromechanical mess. It is intended to be used as a tool which will accelerate the transition from design to application for robots.","PeriodicalId":49947,"journal":{"name":"Journal of Zhejiang University-Science C-Computers & Electronics","volume":"15 1","pages":"1164 - 1173"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1631/jzus.C1400120","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67536061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Examination of the wavelet-based approach for measuring self-similarity of epileptic electroencephalogram data 基于小波的癫痫病脑电图数据自相似度测量方法研究

Journal of Zhejiang University-Science C-Computers & Electronics Pub Date : 2014-12-01 DOI: 10.1631/jzus.C1400126

S. Janjarasjitt

{"title":"Examination of the wavelet-based approach for measuring self-similarity of epileptic electroencephalogram data","authors":"S. Janjarasjitt","doi":"10.1631/jzus.C1400126","DOIUrl":"https://doi.org/10.1631/jzus.C1400126","url":null,"abstract":"Self-similarity or scale-invariance is a fascinating characteristic found in various signals including electroencephalogram (EEG) signals. A common measure used for characterizing self-similarity or scale-invariance is the spectral exponent. In this study, a computational method for estimating the spectral exponent based on wavelet transform was examined. A series of Daubechies wavelet bases with various numbers of vanishing moments were applied to analyze the self-similar characteristics of intracranial EEG data corresponding to different pathological states of the brain, i.e., ictal and interictal states, in patients with epilepsy. The computational results show that the spectral exponents of intracranial EEG signals obtained during epileptic seizure activity tend to be higher than those obtained during non-seizure periods. This suggests that the intracranial EEG signals obtained during epileptic seizure activity tend to be more self-similar than those obtained during non-seizure periods. The computational results obtained using the wavelet-based approach were validated by comparison with results obtained using the power spectrum method.","PeriodicalId":49947,"journal":{"name":"Journal of Zhejiang University-Science C-Computers & Electronics","volume":"30 1","pages":"1147 - 1153"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1631/jzus.C1400126","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67536220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Generation maintenance scheduling based on multiple objectives and their relationship analysis 基于多目标的发电机组维护调度及其关系分析

Journal of Zhejiang University-Science C-Computers & Electronics Pub Date : 2014-11-11 DOI: 10.1631/jzus.C1400030

Junpeng Zhan, C. Guo, Q. Wu, Lu-liang Zhang, H. Fu

{"title":"Generation maintenance scheduling based on multiple objectives and their relationship analysis","authors":"Junpeng Zhan, C. Guo, Q. Wu, Lu-liang Zhang, H. Fu","doi":"10.1631/jzus.C1400030","DOIUrl":"https://doi.org/10.1631/jzus.C1400030","url":null,"abstract":"In a market environment of power systems, each producer pursues its maximal profit while the independent system operator is in charge of the system reliability and the minimization of the total generation cost when generating the generation maintenance scheduling (GMS). Thus, the GMS is inherently a multi-objective optimization problem as its objectives usually conflict with each other. This paper proposes a multi-objective GMS model in a market environment which includes three types of objectives, i.e., each producer’s profit, the system reliability, and the total generation cost. The GMS model has been solved by the group search optimizer with multiple producers (GSOMP) on two test systems. The simulation results show that the model is well solved by the GSOMP with a set of evenly distributed Pareto-optimal solutions obtained. The simulation results also illustrate that one producer’s profit conflicts with another one’s, that the total generation cost does not conflict with the profit of the producer possessing the cheapest units while the total generation cost conflicts with the other producers’ profits, and that the reliability objective conflicts with the other objectives.","PeriodicalId":49947,"journal":{"name":"Journal of Zhejiang University-Science C-Computers & Electronics","volume":"15 1","pages":"1035-1047"},"PeriodicalIF":0.0,"publicationDate":"2014-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1631/jzus.C1400030","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67535141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 21

Sub-channel shared resource allocation for multi-user distributed MIMO-OFDM systems 多用户分布式MIMO-OFDM系统的子信道共享资源分配

Journal of Zhejiang University-Science C-Computers & Electronics Pub Date : 2014-11-01 DOI: 10.1631/jzus.C1400049

Na-e Zheng, You Zhou, Haiqin Hu, Sheng Wang

{"title":"Sub-channel shared resource allocation for multi-user distributed MIMO-OFDM systems","authors":"Na-e Zheng, You Zhou, Haiqin Hu, Sheng Wang","doi":"10.1631/jzus.C1400049","DOIUrl":"https://doi.org/10.1631/jzus.C1400049","url":null,"abstract":"Well-controlled resource allocation is crucial for promoting the performance of multiple input multiple output orthogonal frequency division multiplexing (MIMO-OFDM) systems. Recent studies have focused primarily on traditional centralized systems or distributed antenna systems (DASs), and usually assumed that one sub-carrier or sub-channel is exclusively occupied by one user. To promote system performance, we propose a sub-channel shared resource allocation algorithm for multi-user distributed MIMO-OFDM systems. Each sub-channel can be shared by multiple users in the algorithm, which is different from previous algorithms. The algorithm assumes that each user communicates with only two best ports in the system. On each sub-carrier, it allocates a sub-channel in descending order, which means one sub-channel that can minimize signal to leakage plus noise ratio (SLNR) loss is deleted until the number of remaining sub-channels is equal to that of receiving antennas. If there are still sub-channels after all users are processed, these sub-channels will be allocated to users who can maximize the SLNR gain. Simulations show that compared to other algorithms, our proposed algorithm has better capacity performance and enables the system to provide service to more users under the same capacity constraints.","PeriodicalId":49947,"journal":{"name":"Journal of Zhejiang University-Science C-Computers & Electronics","volume":"15 1","pages":"1048 - 1057"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1631/jzus.C1400049","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67535680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An extended processing scheme for coherent integration and parameter estimation based on matched filtering in passive radar 一种基于匹配滤波的无源雷达相干积分和参数估计扩展处理方案

Journal of Zhejiang University-Science C-Computers & Electronics Pub Date : 2014-11-01 DOI: 10.1631/jzus.C1400074

Xin Guan, L. Zhong, Donghui Hu, Chibiao Ding

{"title":"An extended processing scheme for coherent integration and parameter estimation based on matched filtering in passive radar","authors":"Xin Guan, L. Zhong, Donghui Hu, Chibiao Ding","doi":"10.1631/jzus.C1400074","DOIUrl":"https://doi.org/10.1631/jzus.C1400074","url":null,"abstract":"In passive radars, coherent integration is an essential method to achieve processing gain for target detection. The cross ambiguity function (CAF) and the method based on matched filtering are the most common approaches. The method based on matched filtering is an approximation to CAF and the procedure is: (1) divide the signal into snapshots; (2) perform matched filtering on each snapshot; (3) perform fast Fourier transform (FFT) across the snapshots. The matched filtering method is computationally affordable and can offer savings of an order of 1000 times in execution speed over that of CAF. However, matched filtering suffers from severe energy loss for high speed targets. In this paper we concentrate mainly on the matched filtering method and we use keystone transform to rectify range migration. Several factors affecting the performance of coherent integration are discussed based on the matched filtering method and keystone transform. Modified methods are introduced to improve the performance by analyzing the impacts of mismatching, precision of the keystone transform, and discretization. The modified discrete chirp Fourier transform (MDCFT) is adopted to rectify the Doppler expansion in a multi-target scenario. A novel velocity estimation method is proposed, and an extended processing scheme presented. Simulations show that the proposed algorithms improve the performance of matched filtering for high speed targets.","PeriodicalId":49947,"journal":{"name":"Journal of Zhejiang University-Science C-Computers & Electronics","volume":"15 1","pages":"1071 - 1085"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1631/jzus.C1400074","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67535460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Performance improvement for applying network virtualization in fiber-wireless (FiWi) access networks 在FiWi接入网中应用网络虚拟化的性能改进

Journal of Zhejiang University-Science C-Computers & Electronics Pub Date : 2014-11-01 DOI: 10.1631/jzus.C1400044

Qing-long Dai, G. Shou, Y. Hu, Zhigang Guo

引用次数: 9

Performance-driven assignment and mapping for reliable networks-on-chips 可靠片上网络的性能驱动分配和映射

Journal of Zhejiang University-Science C-Computers & Electronics Pub Date : 2014-11-01 DOI: 10.1631/jzus.C1400055

Qian-qi Le, Guo-wu Yang, W. Hung, Xiaoyu Song, F. Fan

{"title":"Performance-driven assignment and mapping for reliable networks-on-chips","authors":"Qian-qi Le, Guo-wu Yang, W. Hung, Xiaoyu Song, F. Fan","doi":"10.1631/jzus.C1400055","DOIUrl":"https://doi.org/10.1631/jzus.C1400055","url":null,"abstract":"Network-on-chip (NoC) communication architectures present promising solutions for scalable communication requests in large system-on-chip (SoC) designs. Intellectual property (IP) core assignment and mapping are two key steps in NoC design, significantly affecting the quality of NoC systems. Both are NP-hard problems, so it is necessary to apply intelligent algorithms. In this paper, we propose improved intelligent algorithms for NoC assignment and mapping to overcome the drawbacks of traditional intelligent algorithms. The aim of our proposed algorithms is to minimize power consumption, time, area, and load balance. This work involves multiple conflicting objectives, so we combine multiple objective optimization with intelligent algorithms. In addition, we design a fault-tolerant routing algorithm and take account of reliability using comprehensive performance indices. The proposed algorithms were implemented on embedded system synthesis benchmarks suite (E3S). Experimental results show the improved algorithms achieve good performance in NoC designs, with high reliability.","PeriodicalId":49947,"journal":{"name":"Journal of Zhejiang University-Science C-Computers & Electronics","volume":"10 1","pages":"1009 - 1020"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1631/jzus.C1400055","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67535805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Coupling analysis of transcutaneous energy transfer coils with planar sandwich structure for a novel artificial anal sphincter 新型人工肛门括约肌经皮平面夹层结构能量传递线圈的耦合分析

Journal of Zhejiang University-Science C-Computers & Electronics Pub Date : 2014-11-01 DOI: 10.1631/jzus.C1400062

L. Ke, Guo-zheng Yan, Sheng Yan, Zhi-wu Wang, Da-sheng Liu

{"title":"Coupling analysis of transcutaneous energy transfer coils with planar sandwich structure for a novel artificial anal sphincter","authors":"L. Ke, Guo-zheng Yan, Sheng Yan, Zhi-wu Wang, Da-sheng Liu","doi":"10.1631/jzus.C1400062","DOIUrl":"https://doi.org/10.1631/jzus.C1400062","url":null,"abstract":"This paper presents a set of analytical expressions used to determine the coupling coefficient between primary and secondary Litz-wire planar coils used in a transcutaneous energy transfer (TET) system. A TET system has been designed to power a novel elastic scaling artificial anal sphincter system (ES-AASS) for treating severe fecal incontinence (FI), a condition that would benefit from an optimized TET. Expressions that describe the geometrical dimension dependence of self- and mutual inductances of planar coils on a ferrite substrate are provided. The effects of ferrite substrate conductivity, relative permeability, and geometrical dimensions are also considered. To verify these expressions, mutual coupling between planar coils is computed by 3D finite element analysis (FEA), and the proposed expressions show good agreement with numerical results. Different types of planar coils are fabricated with or without ferrite substrate. Measured results for each of the cases are compared with theoretical predictions and FEA solutions. The theoretical results and FEA results are in good agreement with the experimental data.","PeriodicalId":49947,"journal":{"name":"Journal of Zhejiang University-Science C-Computers & Electronics","volume":"15 1","pages":"1021 - 1034"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1631/jzus.C1400062","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67535864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Botnet detection techniques: review, future trends, and issues 僵尸网络检测技术:回顾、未来趋势和问题

Journal of Zhejiang University-Science C-Computers & Electronics Pub Date : 2014-11-01 DOI: 10.1631/jzus.C1300242

Ahmad Karim, R. Salleh, M. Shiraz, Syed Qaiser Ali Shah, Irfan Awan, N. B. Anuar

{"title":"Botnet detection techniques: review, future trends, and issues","authors":"Ahmad Karim, R. Salleh, M. Shiraz, Syed Qaiser Ali Shah, Irfan Awan, N. B. Anuar","doi":"10.1631/jzus.C1300242","DOIUrl":"https://doi.org/10.1631/jzus.C1300242","url":null,"abstract":"In recent years, the Internet has enabled access to widespread remote services in the distributed computing environment; however, integrity of data transmission in the distributed computing platform is hindered by a number of security issues. For instance, the botnet phenomenon is a prominent threat to Internet security, including the threat of malicious codes. The botnet phenomenon supports a wide range of criminal activities, including distributed denial of service (DDoS) attacks, click fraud, phishing, malware distribution, spam emails, and building machines for illegitimate exchange of information/materials. Therefore, it is imperative to design and develop a robust mechanism for improving the botnet detection, analysis, and removal process. Currently, botnet detection techniques have been reviewed in different ways; however, such studies are limited in scope and lack discussions on the latest botnet detection techniques. This paper presents a comprehensive review of the latest state-of-the-art techniques for botnet detection and figures out the trends of previous and current research. It provides a thematic taxonomy for the classification of botnet detection techniques and highlights the implications and critical aspects by qualitatively analyzing such techniques. Related to our comprehensive review, we highlight future directions for improving the schemes that broadly span the entire botnet detection research field and identify the persistent and prominent research challenges that remain open.","PeriodicalId":49947,"journal":{"name":"Journal of Zhejiang University-Science C-Computers & Electronics","volume":"15 1","pages":"943 - 983"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1631/jzus.C1300242","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67534029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 120

Scientific articles recommendation with topic regression and relational matrix factorization 用主题回归和关系矩阵分解进行科学文章推荐

Journal of Zhejiang University-Science C-Computers & Electronics Pub Date : 2014-11-01 DOI: 10.1631/jzus.C1300374

Ming Yang, Yingming Li, Zhongfei Zhang

{"title":"Scientific articles recommendation with topic regression and relational matrix factorization","authors":"Ming Yang, Yingming Li, Zhongfei Zhang","doi":"10.1631/jzus.C1300374","DOIUrl":"https://doi.org/10.1631/jzus.C1300374","url":null,"abstract":"In this paper we study the problem of recommending scientific articles to users in an online community with a new perspective of considering topic regression modeling and articles relational structure analysis simultaneously. First, we present a novel topic regression model, the topic regression matrix factorization (tr-MF), to solve the problem. The main idea of tr-MF lies in extending the matrix factorization with a probabilistic topic modeling. In particular, tr-MF introduces a regression model to regularize user factors through probabilistic topic modeling under the basic hypothesis that users share similar preferences if they rate similar sets of items. Consequently, tr-MF provides interpretable latent factors for users and items, and makes accurate predictions for community users. To incorporate the relational structure into the framework of tr-MF, we introduce relational matrix factorization. Through combining tr-MF with the relational matrix factorization, we propose the topic regression collective matrix factorization (tr-CMF) model. In addition, we also present the collaborative topic regression model with relational matrix factorization (CTR-RMF) model, which combines the existing collaborative topic regression (CTR) model and relational matrix factorization (RMF). From this point of view, CTR-RMF can be considered as an appropriate baseline for tr-CMF. Further, we demonstrate the efficacy of the proposed models on a large subset of the data from CiteULike, a bibliography sharing service dataset. The proposed models outperform the state-of-the-art matrix factorization models with a significant margin. Specifically, the proposed models are effective in making predictions for users with only few ratings or even no ratings, and support tasks that are specific to a certain field, neither of which has been addressed in the existing literature.","PeriodicalId":49947,"journal":{"name":"Journal of Zhejiang University-Science C-Computers & Electronics","volume":"15 1","pages":"984 - 998"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1631/jzus.C1300374","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67535057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2