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Marine information technology:the best is yet to come

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Frontiers of Information Technology & Electronic Engineering 2018年第8期19卷 947-950页

作者： Wen XU Yuan-liang MA Fumin ZHANG Daniel ROUSEFF Fei JI Jun-hong CUI Hussein YAHIA College of lnformation Science and Electrontc Engmeermg Zhejiang UniversityHangzhou 310027China school of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China school of Electncal and Computer Engineering Georgia Institute of TechnologyAtlantaGA 30332USA Applied Physics Laboratory University of WashingtonSeattleWA 98105USA school of Electronic and lnformation Engineering South China University of TechnologyGuangzhou 510641China Smart Ocean Research Center Jilin UniversityChangchun 130012China Research Center INRIA Bordeaux-South West Talence 33405France

Marine information technology(MarineIT)involves marine information gathering,transmission,processing,and ***,this topic has been referred to in the context of acoustic,optical,and electromagnetic sensing of the ocean environment,most notably sonar/radar processing and satellite remote *** its embodiment becomes enriched and its scope extends,particularly accompanied

关键词：海洋环境信息技术卫星遥感上下文

A 155 Mbps laser diode driver with automatic power and extinction ratio control

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1346-1350页

作者： CHEN Xiao-fei ZOU Xue-cheng LIN Shuang-xi LIU Zheng-lin JIN Hai Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China school of Electric and lnformation Engineering Wuhan Institute of Technology Wuhan 430073 China Cluster and Grid Computing Laboratory Huazhong University of Science and Technology Wuhan 430074 China

An integrated laser diode driver(LDD) driving an edge-emitting laser diode was designed and fabricated by 0.35 μm BiCMOS technology. This paper proposes a scheme which combines the automatic power control loop and temperature com-pensation for modulation current in order to maintain constant extinction ratio and average optical power. To implement tem-perature compensation for modulation current,a novel circuit which generates a PTAT current by using the injecting base current of a bipolar transistor in saturation region,and alternates the amplifier feedback loop(closed or not) to control the state of the current path is presented. Simulation results showed that programmed by choice of external resistors,the IC can provide modu-lation current from 5 mA to 85 mA with temperature compensation adjustments and independent bias current from 4 mA to 100 mA. Optical test results showed that clear eye-diagrams can be obtained at 155 Mbps,with the output optical power being nearly constant,and the variation of extinction ratio being lower than 0.7 dB.

关键词：激光器二极管自动功率控制消光系数温度补偿

Spectrum sensing in ultra-wideband system based on cognitive radio

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通讯和计算机（中英文版） 2008年第11期5卷 37-41页

作者： QIN Ji-xin ZHANG Shi-bing school of Electronics and lnformation Nantong University Nantong 226019 China

The radio frequency spectrum is a scarce natural resource and its efficiency has attracted lots of attention in both academia and industry. A fundamental problem facing the future wireless systems is where and how to find suitable spectrum bands to satisfy the demand of the consumer s insatiable appetite for data rate and enable new consumer market segments. A promising technique to improve the spectrum utilization is the ultra-wideband access based on cognitive radio (UWB-CR). Spectrum sensing, as a key enabling functionality in cognitive radio networks, needs to reliably detect signals from primary radios to avoid harmful interference. This paper is focused on the spectrum sensing technique. First, architecture of UWB-CR system was proposed. Then an overview of the spectrum sensing schemes was provided and compared. It is concluded that the optimal spectrum sensing scheme for UWB-CR system is the matched filter detection.

关键词：无线电频谱无线通信系统通信技术探测信号

Human-computer interactive model in pervasive environment

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通讯和计算机（中英文版） 2009年第9期6卷 28-34页

作者： LIU Hong LIU Fu-min school of lnformation Science and Engineering Shandong Normal University Jinan 250014 China

This paper presents a human-computer interaction model in pervasive environment based on dynamic sharing niche technology. It begins with a discussion of some important issues related to human-computer interaction. Then it describes niched co-evolving approach, and based on dynamic sharing niche technology, the group model and classified algorithm is introduced. At last, it further explores sharing learning for increasing the self-adaptation of human-computer interaction and discusses directions for future research.

关键词：人机交互模型人机互动环境细分市场分类算法自我学习共享技术

Proposal for a cross layer scheme for real-time wireless video

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1690-1694页

作者： JEYARAJ Arulsaravana CHENG Liang EL ZARKI Magda EECS Department the Henry Samueli School of Engineering University of California Irvine CA-92697 USA NVIDIA Corporation Santa Clara California CA-95050 USA CS Department DonaM Bren School of lnformation ＆ Computer Sciences University of California Irvine CA-92697 USA

This paper focuses on the design of the cross layer between the video application layer and the MIMO physical layer. MIMO physical layer research has promised an enormous increase in the capacity of wireless communication systems. Also MIMO wireless systems operate under fading conditions where the channel faces arbitrary fluctuations. Since the wireless channel changes over each coherence period, the capacity of the wireless channel, given the power constraints, changes. Hence to make efficient use of the available capacity one needs to adapt the video bit rate. However it is impossible to adapt at the application layer as changing the parameters of the video takes more time than the coherence period of the channel. In this paper we address this problem through a novel solution and also investigate its performance through a simulation study.

关键词： CBR MIMO 自适应调制多样性交换层设计功率控制 V-BLAST FGS

Remove Redundancy Samples for SVM in A Chinese Word Segmentation Task

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通讯和计算机（中英文版） 2006年第5期3卷 103-107页

作者： Feiliang Ren Tianshun Yao school of lnformation Science and Engineering Northeastern University Shenyang 110004 China

This pap r proposes an algorithm that can remove a large number of redundancy samples in a task of using SVM for Chinese word segmentation, and it will not drop much of the final experimental performance. This can ease the training of Chinese word segmentation to a certain extent. This algorithm is fast and needs no extra cost. Both theoretical analysis and experiments show that this algorithm works better, it removes almost 45% of the redundancy samples and the precision ration of our Chinese word segmentation drops less than 3%.1

关键词：文字处理变参数系统软件开发数据处理

Algorithms for mesh repairing to represent automobile parts

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Journal of Modern Transportation 2011年第4期19卷 252-260页

作者： Weiguo LI Wenhua YE Wenliang CHEN College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China school of Mathematics and lnformation Technology Nanjing Xiaozhuang University Nanjing 210000 China

In representing automobile parts with mesh in the field of reverse engineering or finite element generation, the mesh reconstruction and data exchanging between different CAD/CAM systems often introduce many invisible topological and geometrical errors into mesh. These artifacts can cause serious problems in subsequent operations such as finite element analysis, reverse engineering, animation, and simulation. In this study we propose a practical method for repairing topological and geometrical errors on mesh. First, coincident vertices during mesh input are removed, fol- lowed by the identification of non-manifold vertices and edges. The non-manifold vertices are modified, and the facets having non-manifold edges are removed. Finally, faces that have the wrong orientations in the mesh are re-oriented. Experiments show that our methods can eliminate most common mesh errors quickly and effectively. The refined mesh can be properly used in subsequent operations.

关键词： mesh topological repairing geometrical repairing non-manifold vertices non-manifold edges automobile naris: finite element

Decoding of QOSTBC Concatenates BCH Code Based on Parallel Interference Cancellation

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Journal of Donghua University(English Edition) 2011年第3期28卷 267-270页

作者：闫正航杨宇航 MA Maode LU Yilong Department of Electronic Engineering Shanghai Jiaotong Universiry Shanghai 200240 China College of lnformation Science ＆Engineering Henan University of Technology Zhengzhou 450001 China school of Electrical Electronic Engineering Nanyang Technological University 689798 Singapore

It has been shown that quasi orthogonal space time block code (QOSTBC) can achieve high transmission rate with partial diversity. In this paper, a QOSTBC concatenating Bose-Chaudhuri-Hocquenghem (BCH) code structure is presented. At the receiver, pairwise detection and error correction are first implemented. The decoded data are regrouped. Parallel interference cancellation (PIC) and dual orthogonal space time block code (OSTBC) decoding are deployed to the regrouped data. The pure concatenated scheme is shown to have higher diversity order and better error performance at high signal-to-noise ratio (SNR) scenario than both QOSTBC and OSTBC schemes. The PIC and dual OSTBC decoding algorithm can further obtain approximate 1.2 dB gains than the pure concatenated scheme at 10-6 bit error probability.

关键词： OSTBC QOSTBC BCH 代码照片

MPHM:Model poisoning attacks on federal learning using historical information momentum

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Security and Safety 2023年第4期2卷 6-18页

作者： Lei Shi Zhen Chen Yucheng Shi Lin Wei Yongcai Tao Mengyang He Qingxian Wang Yuan Zhou Yufei Gao school of Cyber Science and Engineering Zhengzhou UniversitySongShan LaboratoryZhengzhou 450000China College of Intelligence and Computing Tianjin University300072 TianjinChina school of Computer and Artificial Intelligence Zhengzhou University450000 ZhengzhouChina Zhengzhou Zhengda lnformation Technology Co. Ltd450001 ZhengzhouChina

Federated learning(FL)development has grown increasingly strong with the increased emphasis on data for individuals and *** learning allows individual participants to jointly train a global model without sharing local data,which significantly enhances data ***,federated learning is vulnerable to poisoning attacks by malicious *** federated learning does not have access to the participants’training process,i.e.,attackers can compromise the global model by uploading elaborate malicious local updates to the server under the guise of normal *** model poisoning attacks usually add small perturbations to the local model after it is trained to craft harmful local updates and the attacker finds the appropriate perturbation size to bypass robust detection methods and corrupt the global model as much as *** contrast,we propose a novel model poisoning attack based on the momentum of history information(MPHM),that is,the attacker makes new malicious updates by dynamically crafting perturbations using the historical information in the local training,which will make the new malicious updates more effective and *** attack aims to indiscriminately reduce the testing accuracy of the global model with minimal *** show that in the classical defense case,our attack can significantly corrupt the accuracy of the global model compared to other advanced poisoning attacks.

关键词： Federated learning Poisoning attacks Security Privacy