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Three novel opportunistic scheduling algorithms in CoMP-CSB scenario

science china(information sciences) 2013年第8期56卷 250-261页

作者： WANG Hao LIU Nan wu Ping PAN ZhiWen YOU XiaoHu National Mobile Communications Research Laboratory School of Information Science and EngineeringSoutheast University Signal and System at Department of engineering sciences Uppsala University

Coordinated scheduling/beamforming(CSB),which belongs to the coordinated multi-point(CoMP) transmission,has received lots of attention recently due to its great potential to mitigate inter-cell interference(ICI) and to increase the cell-edge throughput,and meanwhile it only requires limited base station cooperation and is easy to ***,to the best of our knowledge,there are no effective scheduling algorithms with low complexity and overhead in CoMP-CSB scenario as ***,in this paper,we propose three novel opportunistic scheduling algorithms in CoMP-CSB *** of them jointly consider the intended channel condition of the scheduled user from its serving cell and the orthogonality between the intended channel and the corresponding interference channels to concurrently scheduled users in nearby cells,thus exploiting multi-user diversity(MUD) and mitigating ICI at the same *** 1 cooperatively chooses the most orthogonal user pair within a candidate user set in which all users have a large local channel feedback,while Algorithm 2 concurrently schedules the user pair with the largest ratio between the local channel feedbacks and the aforementioned orthogonality within the same candidate user *** 3 performs in the way similar to the proportional fairness scheduling,while making a proper modification for its usage in CoMP-CSB *** performance of the proposed scheduling algorithms are evaluated through *** show that,they all can significantly enhance the received signal to interference plus noise ratio(SINR) with relatively good fairness guarantee,thus achieving larger throughputs and utilities than several well-known scheduling *** 2 even outperforms Algorithm 1 when the aforementioned candidate user set is big enough in size and has a bit more overhead/***,Algorithms 3 is the best one among all the three proposed algorithms,but it requires more overhead/complexity than Alg

关键词： coordinated multi-point(CoMP) coordinated scheduling/beamforming(CSB) inter-cell interference(ICI) multi-user diversity(MUD) opportunistic scheduling.

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User abnormal behavior analysis based on neural network clustering

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The Journal of china Universities of Posts and Telecommunications 2016年第3期23卷 29-36,44页

作者： Zheng Ruijuan Chen Jing Zhang Mingchuan Zhu Junlong wu Qingtao College of information engineering Henan University of Science and Technology State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications

It is the premise of accessing and controlling cloud environment to establish the mutual trust relationship between users and clouds. How to identify the credible degree of the user identity and behavior becomes the core problem？ This paper proposes a user abnormal behavior analysis method based on neural network clustering to resolve the problems of over-fitting and flooding the feature information, which exists in the process of traditional clustering analysis and calculating similarity. Firstly, singular value decomposition （SVD） is applied to reduce dimension and de-noise for massive data, where map-reduce parallel processing is used to accelerate the computation speed, and neural network model is used for softening points. Secondly, information entropy is added to hidden layer of neural network model to calculate the weight of each attribute. Finally, weight factor is used to calculate the similarity to make the cluster more accuracy. For the problem of analyzing the mobile cloud user behaviors, the experimental results show that the scheme has higher detection speed （DS） and clustering accuracy than traditional schemes. The proposed method is more suitable for the mobile cloud environment.

关键词： anomaly analysis information security singular value decomposition (SVD) neural network information entropy

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ECC混凝土自由收缩分析

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科技资讯 2024年第16期22卷 146-150页

作者：张盈稼张振亚吴泽旭宁波工程学院建筑与交通工程学院浙江宁波315211

利用有限元分析方法对ECC混凝土进行自由收缩分析,考虑尺寸和钢筋参量对ECC强度的影响。分析结果表明:相同钢筋掺量情况下,随着混凝土强度增加,混凝土内部湿度越大,相同时间内湿度降低量最小;相同混凝土强度下,随着钢筋增量的增加,混凝... 详细信息

利用有限元分析方法对ECC混凝土进行自由收缩分析,考虑尺寸和钢筋参量对ECC强度的影响。分析结果表明:相同钢筋掺量情况下,随着混凝土强度增加,混凝土内部湿度越大,相同时间内湿度降低量最小;相同混凝土强度下,随着钢筋增量的增加,混凝土内部湿度越大,相同时间内湿度降低量最小。综合来看,混凝土强度对混凝土湿度场影响大于钢筋掺量。

关键词：有限元 ECC混凝土湿度强度

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Ga2O3 doping and vacancy effect in KNN-LT lead-free piezoceramics

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Frontiers of Materials science 2017年第4期11卷 344-352页

作者： Zhi TAN Jie XlNG Laiming jianG jianguo ZHU Bo wu College of Materials science and engineering Sichuan University Chengdu 610064 China Sichuan Province Key Laboratory of information Materials and Devices Application Chengdu University of Information Technology Chengdu 610225 China

Ga2O3 was doped into 0.95（K0.48Na0.52）NbO3-0.05LiTaO3 （KNN-LT） cera- mics and its influences on the sintering behavior, phase structure and electrical properties of ceramics were studied. Firstly, SEM observation exhibits that more and more glass phase appears in ceramics with the gradual addition of Ga2O3, which determines the continuous decrease in sintering temperatures. And the addition of Ga2O3 is also found to increase the orthorhombic-tetragonal transition temperature （To-T） of system to a higher level. Secondly, both the density and the coercive field （Ec） of ceramics increase firstly and then decrease with increasing the Ga2O3 content, and the KNN-LT-xGa sample at x = 0.004 shows a pinched P-E hysteresis loop. Finally, the impedance characteristics of KNN-LT-xGa ceramics were investigated at different temperatures, revealing a typical vacancy related conduction mechanism. This work demonstrates that Ga2O3 is a good sintering aid for KNN-based ceramics, and the vacancy plays an important role in the sintering and electrical behaviors of ceramics.

关键词： lead-free piezoceramics Ga2O3 phase structure piezoelectric properties sintering behavior

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PROPAGATION CHARACTERISTICS OF HIGH ORDER LONGITUDINAL MODES IN STEEL STRANDS AND THEIR APPLICATIONS

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Acta Mechanica Solida Sinica 2008年第6期21卷 573-579页

作者： Zenghua Liu Su Liu Bin wu Yinong Zhang Cunfu He College of Mechanical engineering and Applied Electronics technology Beijing University of Technology Beijing 100124 China

Propagation characteristics of high order longitudinal modes of ultrasonic guided waves in seven-wire steel strands are investigated theoretically and experimentally. According to these analysis results, proper longitudinal modes are selected for defect detection in steel strands. Dispersion curves for helical and central wires in a 17.80 mm nominal diameter seven-wire steel strand are numerically obtained firstly, and propagation characteristics of high-order longitudinal modes, such as wave structures, attenuation and dispersion, are analyzed. In experiments, the signals of ultrasonic guided wave at different high frequencies are excited and received at one end of a steel strand by using the same single piezoelectric transducer. The identification of longitudinal modes in the received signals is achieved based on short time Fourier transform. Furthermore, appropriate L（0, 5） mode at 2.54 MHz is chosen for detecting an artificial defect in a helical wire of the steel strand. Results show that high order longitudinal modes in a high frequency range with low dispersion and attenuation whose energy propagates mainly in the center of the wires can be used for defect detection in long range steel strands.

关键词： steel strand ultrasonic guided waves longitudinal modes dispersion attenuation

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Fault Diagnosis of Motor in Frequency Domain Signal by Stacked De-noising Auto-encoder

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Computers, Materials & Continua 2018年第11期57卷 223-242页

作者： Xiaoping Zhao Jiaxin wu Yonghong Zhang Yunqing Shi Lihua Wang school of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China school of information and Control Nanjing University of Information Science and TechnologyNanjing210044China Electrical and Computer engineering New Jersey Institute of TechnologyNewark07102USA

With the rapid development of mechanical equipment,mechanical health monitoring field has entered the era of big *** learning has made a great achievement in the processing of large data of image and speech due to the powerful modeling capabilities,this also brings influence to the mechanical fault diagnosis ***,according to the characteristics of motor vibration signals(nonstationary and difficult to deal with)and mechanical‘big data’,combined with deep learning,a motor fault diagnosis method based on stacked de-noising auto-encoder is *** frequency domain signals obtained by the Fourier transform are used as input to the *** method can extract features adaptively and unsupervised,and get rid of the dependence of traditional machine learning methods on human extraction features.A supervised fine tuning of the model is then carried out by *** Asynchronous motor in Drivetrain Dynamics Simulator system was taken as the research object,the effectiveness of the proposed method was verified by a large number of data,and research on visualization of network output,the results shown that the SDAE method is more efficient and more intelligent.

关键词： Big data deep learning stacked de-noising auto-encoder fourier transform

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铁电材料负电卡效应的研究进展

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现代技术陶瓷 2024年第1期45卷 24-43页

作者：李建厅李俊杰闫汝清白洋齐鲁工业大学大学机械工程学院(山东省科学院) 济南250353 山东机械设计研究院济南250353 成都信息工程大学光电工程学院成都610225 北京科技大学新材料技术研究院北京100083

基于电卡效应的铁电制冷技术具有制冷效率高、绿色环保、操控便捷、易于小型化等优点,具有广阔的制冷应用场景。电卡效应是指铁电等极性材料在外电场作用下电偶极子状态改变引发的等温熵变或绝热温变,包括正电卡效应和负电卡效应。正(负... 详细信息

基于电卡效应的铁电制冷技术具有制冷效率高、绿色环保、操控便捷、易于小型化等优点,具有广阔的制冷应用场景。电卡效应是指铁电等极性材料在外电场作用下电偶极子状态改变引发的等温熵变或绝热温变,包括正电卡效应和负电卡效应。正(负)电卡效应是指对铁电体施加(撤去)电场时,铁电体放热;撤去(施加)电场时,铁电体吸热的现象。正、负电卡效应中从外部环境吸收热量的过程均可用于铁电制冷。除优化热释电系数和击穿场强的传统方案外,正、负电卡效应相结合也被认为是提升铁电材料制冷能力的有效手段。然而,负电卡效应存在研究时间短、材料体系少、物理机制不清晰、调控机理不明确等诸多问题,限制了正、负电卡效应的结合及其应用。本文在回顾电卡效应研究进展的基础上,综述了负电卡效应的物理机制和调控机理,讨论了结合正、负电卡效应提升制冷性能的可行性,并对负电卡效应及正、负电卡效应结合的未来研究进行了展望。本文可为负电卡效应研究及提升铁电材料的制冷能力提供新的思路和方向,推动电卡效应的研究。

关键词：铁电制冷技术电卡效应负电卡效应物理机制

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Distributed cache replacement method for geospatial data using spatiotemporal localitybased sequence

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Geo-Spatial information science 2015年第4期18卷 171-182页

作者： Rui LI Jiapei FAN Xinxing WANG Zhen ZHOU Huayi wu State key Laboratory of information engineering in Surveying Mapping and Remote Sensing(LIESMARS)Wuhan University129 Luoyu RoadWuhan 430079China Collaborative Innovation Center of Geospatial technology Wuhan University129 Luoyu RoadWuhan 430079China

Specific features of tile access patterns can be applied in a cache replacement strategy to a limited distributed high-speed cache for the cloud-based networked geographic information services(NGISs),aiming to adapt to changes in the access distribution of *** taking advantage of the spatiotemporal locality,the sequential features in tile access patterns,and the cache reading performance in the burst mode,this article proposes a tile sequence replacement method,which involves structuring a Least Recently Used(LRU)stack into three portions for the different functions in cache replacement and deriving an expression for the temporal locality and popularity of the relevant tile to facilitate the replacement *** on the spatial characteristics of both the tiles and the cache burst mode with regard to reading data,the proposed method generates multiple tile sequences to reflect spatiotemporal locality in tile access ***,we measure the caching value by a technique based on a weighted-based *** technique draws on the recent access popularity and low caching costs of tile sequences,with the aim of balancing the temporal and spatial localities in tile *** ranks tile sequences in a replacement queue to adapt to the changes in accessed hotspots while reducing the replacement *** results show that the proposed method effectively improves the hit rate and utilization rate for a limited distributed cache while achieving satisfactory response performance and high throughput for users in an ***,it can be adapted to handle numerous data access requests in NGISs in a cloud-based environment.

关键词： spatiotemporal replacement access pattern Least Recently Used(LRU)stack networked GIS

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High performance architecture for unified forward and inverse transform of HEVC

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The Journal of china Universities of Posts and Telecommunications 2017年第3期24卷 16-23页

作者： jiang Lin Wang Xingjun wu Xin Deng Junyong Huang Xingjie school of Electronic engineering Xi'an University of Posts and Telecommunications College of Computer and information science Northeastern University

High efficiency video coding （HEVC） transform algorithm for residual coding uses 2-dimensional （2D） 4 × 4 transforms with higher precision than H.264＇s 4 ×4 transforms, resulting in increased hardware complexity. In this paper, we present a shared architecture that can compute the 4 ~4 forward discrete cosine transform （DCT） and inverse discrete cosine transform （IDCT） of HEVC using a new mapping scheme in the video processor array structure. The architecture is implemented with only adders and shills to an area-efficient design. The proposed architecture is synthesized using ISE 14.7 and implemented using the BEE4 platform with the Virtex-6 FF1759 LX550T field programmable gate array （FPGA）. The result shows that the video processor array structure achieves a maximum operation frequency of 165.2 MHz. The architecture and its implementation are presented in this paper to demonstrate its programmable and high performance.

关键词： HEVC forward and inverse transform reconfigurable architecture video processor array structure

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ZnSe/NiO heterostructure-based chemiresistive-type sensors for low-concentration NO_(2) detection

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Rare Metals 2021年第6期40卷 1632-1641页

作者： Wei Liu Ding Gu jian-Wei Zhang Xiao-Gan Li Marina N.Rumyantseva Alexander M.Gaskov school of Microelectronics Key Laboratory of Liaoning for Integrated Circuits TechnologyDalian University of TechnologyDalian 116024China Liaoning Key Laboratory of Integrated Circuit and Biomedical Electronic System Faculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalian 116024China Laboratory of Chemistry and Physics of Semiconductor and Sensor Materials Chemistry DepartmentMoscow State UniversityMoscow 199991Russia

Novel ZnSe/NiO heterostructure nanocomposites were successfully prepared by one-step hydrothermal *** ZnSe/NiO-based sensor exhibits a response of~96.47% to 8×10^(-6) NO_(2) at 140℃,which is significantly higher than those of intrinsic ZnSe-based(no response)and NiO-based(~19.65%)*** theoretical detection limit(LOD)of the sensor is calculated to be 8.91×10^(-9),indicating that the sensor can be applied to detect the ultralow concentrations of NO_(2).The effect of NiO content on the gas-sensing performance of the nanocomposites was investigated in *** optimal NiO content in the nanocomposite is determined to be15.16%to achieve the highest *** as-fabricated sensor also presents an excellent selectivity to several possible interferents such as methanol,ethanol,acetone,benzene,ammonia and *** enhanced sensing performance can be attributed to the formation of p-p heterostructures between ZnSe and NiO,which induces the charge transfer across the interfaces and yields more active sites.

关键词： ZnSe/NiO heterostructure NO_(2)detection Gas sensors Charge transfer

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