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

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, {4. 2Institute of Computing Technology, Chinese Academy of Sciences, beijing 100190, {4. 3Graduate university of Chinese Academy of Sciences, beijing 10004., {4. 4.ational Computer network Emergency Response Technical Team/Coordination Center of {4., beijing 100029, {4. 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

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Response synchronization: New progress in brain-visual information processing

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Chinese Science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry , Institute of Atmospheric Physics , Chinese Academy of Sciences , beijing 100029, china 2. Commission of the National Natural Science Foundation of china , beijing 100083, china 3. The Center of Information Science , Peking university, beijing 100871, china 4. Open laboratory of Visual Information Processing , Institute of Biophysics , Chinese Academy of Sciences , beijing 100101, china State Key laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National Natural Science Foundation of china Beijing China The Center of Information Science Peking University Beijing China Open laboratory of Visual Information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. Naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

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Carbon isotope ratios of C_(4. plants in loess areas of North china

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Science china Earth Sciences 2006年第1期49卷 97-102页

作者： WANG Guoan1,2,3, HAN Jiamao 2, ZHOU Liping3, XIONG Xiaogang4. TAN Ming2, WU Zhenhai5 & PENG Jun6 1. Department of Plant Nutrition, china Agricultural university, beijing 100094. china 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china 3. College of Environmental Sciences, MOE laboratory for Earth Surface Processes, Peking university, beijing 100871, china 4. Institute of Botany, Chinese Academy of Sciences, beijing 100093, china 5. Northwest Sci-Tech university of Agriculture and Forestry, Yangling 712100, china 6. {14. Center, china Agricultural university, beijing 100094. china 1. Department of Plant Nutrition China Agricultural University Beijing 100094 China 2. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. College of Environmental Sciences MOE Laboratory for Earth Surface Processes Peking University Beijing 100871 China 4. Institute of Botany Chinese Academy of Sciences Beijing 100093 China 5. Northwest Sci-Tech university of Agriculture and Forestry Yangling 712100 China 6. network Center China Agricultural University Beijing 100094 China

Carbon isotope ratios (δ^(13)C) of 89 C_4.plant samples were determined fromthe loess area in North china. δ^(13)C values vary between -10.5per thousand and -14.6per thousandwith a mean of -12.6per thousand. Along a precipitation gradient from the semi-moist area to thesemiarid area, then to the arid area, the δ^(13)C values of C_4.plants show a slight decreasingtrend. The δ^(13)C values of C_4.plants in the dry season are found lower than those in the wetseason. These trends are opposite to those observed for C_3 species.

关键词： C4 plants, carbon isotope ratios, loess area.

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Enhancement and Evolution of TD-SCDMA Systems

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ZTE Communications 2007年第3期5卷 36-43页

作者： Peng Mugen Li Yong Wang Wenbo (wireless Signal Processing and network Lab,beijing university of Posts and {4.,beijing 100876,china)

Time Division-Synchronous Code Division Multiple Access (TD-SCDMA),a home-grown standard for the third generation mobile communications,is already mature and ready for commercial deployment. The enhancement and evolution of the TD-SCDMA system is a hot topic recently. Many strategies for TD-SCDMA enhancements and evolutions have been proposed,but there are no integrated solutions that can jointly consider the development both in the short term and in the long term. This paper discusses four evolution phases,which are proposed according to the key technologies. Phase 1 is about the current TD-SCDMA system. Phase 2 is the short term evolution of TD-SCDMA,i.e.,the period of HSxPA,including the evolution of High Speed Downlink Packet Access (HSDPA),High Speed Uplink Packet Access (HSUPA) and High Speed Packet Access plus (HSPA+). Phase 3 is the Long Term Evolution (LTE). Phase 4.is the Beyond 3G (B3G)/Fourth Generation (4.) mobile communication Time Division Duplex (TDD) system,which is based on TD-SCDMA. Key characters for every evolution phase are discussed,as well as the advanced technologies adopted in the evolution process such as Multiple Input Multiple Output (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM).

关键词： SCDMA Access TD Enhancement and Evolution of TD-SCDMA Systems

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Channel Adaptive Shortest Path Routing for Ad Hoc networks

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The Journal of china Universities of Posts and telecommunications 2003年第3期10卷 1-5页

作者： TIAN Hui, XIE Fang, HU Jian dong, ZHANG Ping (wireless Technology Innovation Labs, beijing university of Posts & telecommunications, {4., P. R. china) wireless Technology Innovation Labs Beijing University of Posts & Telecommunications 北京 100876

Routing in Mobile Ad Hoc network (MANET) is a challenge owing to the dynamicnature of network topology and the resource constraints. To maximize the channel resourceutilization and minimize the network transfer delay along the path, the shortest path with theminimum hops approach is often adopted. However, the quality of wireless channels among the mobilenodes is time varying owing to fading, shadowing and path loss. Considering adaptive channel codingand modulation scheme, the channel state can be characterized by different link throughputs . Ifrouting selection based on the link throughput is implemented, the minimum transfer delay fromsource to destination and the. maximal throughput may be obtained. In this paper, a Channel AdaptiveShortest Path Routing (CASPR) is presented. Based on the adaptive channel coding and modulation,the CASPR transforms the link throughput into the channel quality factor Q and finds the shortestrouting according to the Q measure. Simulation results show that the average path length in theproposed routing scheme may be slightly higher than that of the conventional shortest path with theminimum hops approach, but it can reduce the average transfer delay and increase the packet deliverrate.

关键词： wireless networks ad hoc networks routing

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Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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Science china Earth Sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2, WANG Qingfei1,2 , HUANG Dinghua3 , WAN Li4. YANG Liqiang1,2 & GAO Bangfei1,2 1. State Key laboratory of Geological Processes and Mineral Resources, china university of Geosciences, beijing 100083, china 2. Key laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, china university of Geo- sciences, beijing 100083, china 3. Faculty of Earth Sciences, china university of Geosciences, Wuhan 4.0074. china 4. School of Mathematics and Information Science, Guangzhou university, Guangzhou 5104.5, china 1. State Key laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Key laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 China 3. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China 4. School of Mathematics and Information Science Guangzhou University Guangzhou 510405 China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

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Relaying Selection with network-coded Cooperative Protocols in Aeronautical Communications

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Chinese Journal of Aeronautics 2010年第1期23卷 75-83页

作者： Du Bing,Zhang Jun School of Electronics and Information Engineering,beijing university of Aeronautics and Astronautics,beijing 100191,china [a] School of Electronics Information Engineering Beijing University of Aeronautics Astronautics Beijing 100191 China

In this article, we exploit the idea of network-coded cooperative protocol in aeronautical communications which combines different source nodes＇ information at the relay and joint decoding at the destination. Recently, the network coding in cooperative communications has been categorized into two mainstreams, bit-level and signal-level combinations, which are both discussed in the article. And to be exclusively,multiple access relay channel（MARC） is adopted. The mutual information expressions of both above-cited network-coded protocols are deduced, which prove that without proper selected relays to perform network coding, the spatial diversity of the proposed protocol cannot be obtained. This then leads to search for the selection and grouping algorithms. An adjacency matrix is defined to describe the connectivity of the nodes in one radio contact disk, so that, the selection and grouping of algorithm is equivalent to constructing this adjacency matrix to minimize the system outage probability evaluated in term of the mutual information. Besides, a network-coded cooperative protocol requires the acyclic network, of which the construction is to avoid loop-4.in the matrix. The article ends with simulations to demonstrate the viability of the proposed algorithms.

关键词： communication network coding outage probability mutual information bit-level signal-level

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Very Low-power wireless Communication Technology-ZigBee

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ZTE Communications 2006年第4期4卷 19-23页

作者： Zhang PingKang GuixiaTian Hui(wireless Technology Innovation Institute, beijing university of Posts and telecommunications, {4., china)

The ZigBee as the main supporting technology for the wireless sensor network has received extensive attention. Completed ZigBee protocol kits consist of the high-level application specification, the application convergence layer, the network layer, the data link layer, and the Physical (PHY) layer. The protocols of the network layer and higher ones are set up by the ZigBee Alliance, the physical layer and the Media Access Control (MAC) layer are defined by the IEEE 802.15.4.standard. The IEEE 802.15.4.physical layer simply adopts technologies of mapping from bit to symbol, conversion from symbol to chip sequence, and Offset Quadrature Phase Shift Keying (OQPSK) modulation, avoiding complicated arithmetic such as channel coding. The IEEE 802.15.4.MAC layer adopts Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) technology and supports the sleeping mode. The ZigBee enables low data transmission rate, low power consumption at low cost, and is more suitable for industry monitoring systems, sensor networks, home monitoring systems, and security systems.

关键词： Very Low-power wireless Communication Technology-ZigBee USA data IEEE MAC

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In the development of wireless cognitive science

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Chinese Science Bulletin 2012年第28期57卷 3661-3661页

作者： ZHANG Ping Key laboratory of Universal wireless Communications of Ministry of Education, beijing university of Posts and {4., beijing 100876, china beijing Univ Posts & Telecommun Minist Educ Key Lab Universal Wireless Commun Beijing 100876 Peoples R China

Recently,driven by the technology innovations and application requirements,wireless network technologies developed rapidly with high data rate and wide system bandwidth,which have already changed the way that people u... 详细信息

关键词：无线网络技术认知科学无线电频谱无线接入技术异构网络高数据速率高频谱效率技术创新

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Mobile Ubiquitous network Environment

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ZTE Communications 2007年第1期5卷 54-59页

作者： Zhang Ping, Ji Yang, Feng Zhiyong(Research Center for wireless New Technology, beijing university of Posts and telecommunications, {4., china)

The Mobile Ubiquitous Service Environment (MUSE), established through the coordination and integration of mobile telecommunications and ubiquitous network in the pursuit of Always Best Experience (ABE), represents the major development trend for the next generation mobile wireless network. Research on MUSE will involve the integration of computing model system, service platform system, operating system and terminal structure system, all of which involve exploration and innovation of new networking structure, its control and management as well as way of measuring. The change in network resources triggers the change in network computing models. To make readers have a basic understanding of mobile ubiquitous network environment, this lecture will introduce MUSE in two sections. The first section describes the background of MUSE and its future development prospect. The second section focuses on the design principles and key technologies in MUSE model, which make services realized, as well as the networking structure of MUSE model, and the key technologies and design principles of networking.

关键词： work Mobile Ubiquitous network Environment WCDMA NSE GPP

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