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Information content security on the Internet:the control model and its evaluation

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Science china(Information Sciences) 2010年第1期53卷 30-49页

作者： FANG BinXing1, GUO YunChuan2,3 & ZHOU yuan4 1school of computer, beijing university of posts and telecommunications, beijing 100029, china 2Institute of Computing Technology, Chinese Academy of Sciences, beijing 100190, china 3Graduate university of Chinese Academy of Sciences, beijing 100049, china 4National computer Network Emergency Response Technical Team/Coordination Center of china, beijing 100029, china 1. school of computer Beijing University of Posts and Telecommunications Beijing 100029 China2. Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China4. National Computer Network Emergency Response Technical Team/Coordination Center of China Beijing 100029 China

Flooding of harmful information on the Internet seriously endangers the physiological and mental health of teenagers. Due to the user-friendliness of the Internet as well as the difficulty in the authentication for the access of specific categories of information, curbing the transmission of harmful information, i.e., assuring the information content security (ICS), has become a reasonable yet challenging alternative. At present, there is an urgent need to develop a systematic model that can effectively carry out the curbing. In fact, curbing the transmission of harmful information by way of filtering can be modeled by access control. In the paper, based on the three core-elements of communication, namely, "Who communicates with whom", "How do they communicate" and "What is the content of communication", we propose a control model, called ICCON. Unlike the existing access control, the reference monitor (RM) of our model is placed in the transmission channel, and moreover, an evaluation frame is proposed, through which the effectiveness of the RM in controlling information transmission on the Internet can be quantitatively evaluated.

关键词： content security access control quantitative evaluation

Quick Hosting Capacity Evaluation Based on Distributed Dispatching for Smart Distribution Network Planning with Distributed Generation

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 128-140页

作者： Bing Sun Ruipeng Jing Leijiao Ge yuan Zeng Shimeng Dong Luyang Hou the school of Electrical and Information Engineering Tianjin UniversityTianjin 300072China State Grid Corporation of china BeijingChina the school of computer Science(National Pilot Software Engineering school) Beijing University of Posts and TelecommunicationsBeijingChina

The smart distribution network(SDN)is integrat ing increasing distributed generation(DG)and energy storage(ES).Hosting capacity evaluation is important for SDN plan ning with *** and ES are usually invested by users or a third party,and they may form friendly microgrids(MGs)and operate *** centralized dispatching meth od no longer suits for hosting capacity evaluation of SDN.A quick hosting capacity evaluation method based on distributed optimal dispatching is ***,a multi-objective DG hosting capacity evaluation model is established,and the host ing capacity for DG is determined by the optimal DG planning *** steady-state security region method is applied to speed up the solving process of the DG hosting capacity evalua tion ***,the optimal dispatching models are estab lished for MG and SDN respectively to realize the operating *** the distributed dispatching strategy,the dual-side optimal operation of SDN-MGs can be realized by several iterations of power exchange ***,an SDN with four MGs is conducted considering multiple flexible *** shows that the DG hosting capacity of SDN oversteps the sum of the maximum active power demand and the rated branch ***,the annual DG electricity oversteps the maximum active power demand value.

关键词： Smart distribution network(SDN) microgrid hosting capacity multi-objective optimization distributed opti mal dispatching flexible resource

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Multi-rope Hoist Steel Rope Tension On-line Monitoring System

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Multi-rope Hoist Steel Rope Tension On-line Monitoring Syste...

2012 National Conference on Information Technology and computer Science

作者： Liu Jian school of Information and Communication Engineering beijing university of posts and telecommunications beijing,china Liu yuan-xiang Zhenghui corporation of Fenxi Mine Group Shanxi Coking Coal Group CO.,LTD.Jiexiu,china

A multi-rope hoist steel rope tension on-line monitoring system is introduced in this paper,which consists of hydraulic sensors,data acquisition and sending devices,wireless communication devices and *** system monitors the tension of multi-rope hoist steel ropes,in order to get the actual load of the *** error happens the system can alarm to avoid accidents,such as serious imbalance of the steel ropes and hoist overload.

关键词： multi-rope hoist steel rope tension on-line monitor tension imbalance

Distributed Consensus Control for Second-Order Agents with Fixed Topology and Time-Delay

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Distributed Consensus Control for Second-Order Agents with F...

第二十六届中国控制会议

作者： Lin Peng1,Jia Yingmin1,Du Junping2,yuan Shiying3 1.The Seventh Research Division,Beihang university (BUAA),beijing 100083,P.R.china2.beijing Key Laboratory of Intelligent telecommunications Software and Multimedia,school of computer Science and Technology,beijing university of posts and telecommunications,beijing 100876,P.R.china3.school of Electrical and Automation,Henan Polytechnic university,Jiaozuo 454000,Henan,P.R.china

In this paper,distributed consensus control is investigated for networks of agents with double integrator *** kinds of networks are analyzed,i.e.,directed networks with fixed topology and undirected networks with fixed topology and *** each of the networks,a sufficient and necessary condition is given to guarantee the *** is proved that the largest tolerable time-delay is only related to the largest eigenvalue of the graph ***,two numerical examples are provided to illustrate the obtained results.

关键词： Consensus Fixed topology Time-delay Double Integrator Dynamics

FGM-SPCL:Open-Set Recognition Network for Medical Images Based on Fine-Grained Data Mixture and Spatial Position Constraint Loss

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Chinese Journal of Electronics 2024年第4期33卷 1023-1033页

作者： Ruru ZHANG Haihong E Lifei yuan Yanhui WANG Lifei WANG Meina SONG school of computer Science Beijing University of Posts and Telecommunications Engineering Research Center of Information Networks Ministry of Education Hebei Eye Hospital

The current intelligent auxiliary diagnosis models all follow the closed-set recognition setting. After the model is deployed online, the input data is often not completely controlled. Diagnosing an untrained disease as a known category would lead to serious medical malpractice. Therefore, realizing the open-set recognition is significant to the safe operation of the intelligent auxiliary diagnosis model. Currently, most open-set recognition models are studied for natural images, and it is very challenging to obtain clear and concise decision boundaries between known and unknown classes when applied to fine-grained medical images. We propose an open-set recognition network for medical images based on fine-grained data mixture and spatial position constraint loss(FGM-SPCL) in this *** the fine graininess of medical images and the diversity of unknown samples, we propose a fine-grained data mixture(FGM) method to simulate unknown data by performing a mixing operation on known data to expand the coverage of unknown data difficulty levels. In order to obtain a concise and clear decision boundary, we propose a spatial position constraint loss(SPCL) to control the position distribution of prototypes and samples in the feature space and maximize the distance between known classes and unknown classes. We validate on a private ophthalmic OCT dataset, and extensive experiments and analyses demonstrate that FGM-SPCL outperforms state-of-the-art models.

关键词： Analytical models Fine-grained image recognition Prototypes Aerospace electronics Spatial databases Robustness Data models

A Lambda Layer-Based Convolutional Sequence Embedding Model for Click-Through Rate Prediction

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Wuhan university Journal of Natural Sciences 2024年第3期29卷 198-208页

作者： ZHOU Liliang yuan Shili FENG Zijian DAI Guilan ZHOU Guofu Tenth Research Institute China Electronics Technology Group CorporationChengdu 610000SichuanChina Department of computer Science Nanjing University of Posts and TelecommunicationsNanjing 210023JiangsuChina Research Institution of Information Technology Tsinghua UniversityBeijing 100084China school of computer Science Wuhan UniversityWuhan 430072HubeiChina

In the era of intelligent economy, the click-through rate(CTR) prediction system can evaluate massive service information based on user historical information, and screen out the products that are most likely to be favored by users, thus realizing customized push of information and achieve the ultimate goal of improving economic benefits. Sequence modeling is one of the main research directions of CTR prediction models based on deep learning. The user's general interest hidden in the entire click history and the short-term interest hidden in the recent click behaviors have different influences on the CTR prediction results, which are highly important. In terms of capturing the user's general interest, existing models paid more attention to the relationships between item embedding vectors(point-level), while ignoring the relationships between elements in item embedding vectors(union-level). The Lambda layer-based Convolutional Sequence Embedding(LCSE) model proposed in this paper uses the Lambda layer to capture features from click history through weight distribution, and uses horizontal and vertical filters on this basis to learn the user's general preferences from union-level and point-level. In addition, we also incorporate the user's short-term preferences captured by the embedding-based convolutional model to further improve the prediction results. The AUC(Area Under Curve) values of the LCSE model on the datasets Electronic, Movie & TV and MovieLens are 0.870 7, 0.903 6 and 0.946 7, improving 0.45%, 0.36% and 0.07% over the Caser model, proving the effectiveness of our proposed model.

关键词： click-through rate prediction deep learning attention mechanism convolutional neural network

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A Barzilai-Borwein conjugate gradient method

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Science china Mathematics 2016年第8期59卷 1511-1524页

作者： DAI YuHong KOU caixia LSEC Institute of Computational Mathematics and Scientific/Engineering ComputingAcademy of Mathematics and Systems Science Chinese Academy of Sciences school of Science Beijing University of Posts and Telecommunications

The linear conjugate gradient method is an optimal method for convex quadratic minimization due to the Krylov subspace minimization property. The proposition of limited-memory BFGS method and Barzilai-Borwein gradient method, however, heavily restricted the use of conjugate gradient method for largescale nonlinear optimization. This is, to the great extent, due to the requirement of a relatively exact line search at each iteration and the loss of conjugacy property of the search directions in various occasions. On the contrary, the limited-memory BFGS method and the Barzilai-Bowein gradient method share the so-called asymptotical one stepsize per line-search property, namely, the trial stepsize in the method will asymptotically be accepted by the line search when the iteration is close to the solution. This paper will focus on the analysis of the subspace minimization conjugate gradient method by yuan and Stoer(1995). Specifically, if choosing the parameter in the method by combining the Barzilai-Borwein idea, we will be able to provide some efficient Barzilai-Borwein conjugate gradient(BBCG) methods. The initial numerical experiments show that one of the variants, BBCG3, is specially efficient among many others without line searches. This variant of the BBCG method might enjoy the asymptotical one stepsize per line-search property and become a strong candidate for large-scale nonlinear optimization.

关键词： conjugate gradient method subspace minimization Barzilai-Bowein gradient method line search descent property global convergence

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The Study on Two Kinds of Modified LMS Equalizers for Underwater Acoustic Communication

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The Study on Two Kinds of Modified LMS Equalizers for Underw...

2011 IEEE International Conference on Information Theory and Information Security(ICITIS 2011)

作者： Jing Gang 1) ,2) , Jinxiang Fen g3) , Hui Zhou 3) , Yu yuan 3) , Jing Wuan 3),4) ,* 1) 750 Test Range, china Shipbuilding Industry Corporation, Kunming, china 2) school of Marine Engineering, Northwestern Polytechnical university, Xi’an, china 3) school of Information Science and Engineering, Yunnan university, Kunming, china 4) Institute of Acoustics, Chinese Academy of Sciences, beijing, china

It is necessary to add an equalizer to reduce the serious inter-symbol interference (ISI) caused by the multipath effect of underwater acoustic communication (UAC) in order to improve the quality of UAC. The traditional LMS equalizer (LMSE) is suitable only for the situation where the channel environment is statistically stationary. This tends to limit its application in UAC because its convergence and tracking capabilities are both declined. This paper studies two kinds of modified LMS equalizers, variable step size LMS equalizer (VLMSE) and variable step size LMS decision feedback equalizer (VLMSFE), which can improve the convergence of the traditional LMS equalizer and reduce the error code rate greatly, thus improve the quality of UAC system. Theoretical analysis and computer simulation supports the above conclusion.

关键词： UAC ISI VLMSE VLMSDFE

Recent Advances on Human-computer Dialogue

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CAAI Transactions on Intelligence Technology 2016年第4期1卷 303-312页

作者： Xiaojie Wang caixia yuan Center for Intelligence Science and Technology School of Computer Science Beijing University of Posts and Telecommunications Beijing 100876 China

Human-computer dialogue systems provide a natural language based interface between human and computers. They are widely demanded in network information services, intelligent accompanying robots, and so on. A Human-computer dialogue system typically consists of three parts, namely Natural Language Understanding （NLU）, Dialogue Management （DM） and Natural Language Generation （NLG）. Each part has several different subtasks. Each subtask has been received lots of attentions, many improvements have been achieved on each subtask, respectively. But systems built in traditional pipeline way, where different subtasks are assembled sequently, suffered from some problems such as error accu- mulation and expanding, domain transferring. Therefore, researches on jointly modeling several subtasks in one part or cross different parts have been prompted greatly in recent years, especially the rapid developments on deep neural networks based joint models. There is even a few work aiming to integrate all subtasks of a dialogue system in a single model, namely end-to-end models. This paper introduces two basic frames of current dialogue systems and gives a brief survey on recent advances on variety subtasks at first, and then focuses on joint models for multiple subtasks of dialogues. We review several different joint models including integration of several subtasks inside NLU or NLG, jointly modeling cross NLG and DM, and jointly modeling through NLU, DM and NLG. Both advantages and problems of those joint models are discussed. We consider that the joint models, or end-to-end models, will be one important trend for developing Human-computer dialogue systems.

关键词： Human-computer dialogue system Natural Language Understanding Dialogue Management Natural Language Generation Joint model