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Multi-agent decision support system for missile defense based on improved PSO algorithm

Journal of Systems Engineering and Electronics 2017年第3期28卷 514-525页

作者： Zilong Cheng li fan Yulin Zhang College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China Academy of Equipment Beijing 101416China

Ballistic missile defense system (BMDS) is important for its special role in ensuring national security and maintaining strategic balance. Research on modeling and simulation of the BMDS beforehand is essential as developing a real one requires lots of manpower and resources. BMDS is a typical complex system for its nonlinear, adaptive and uncertainty characteristics. The agent-based modeling method is well suited for the complex system whose overall behaviors are determined by interactions among individual elements. A multi-agent decision support system (DSS), which includes missile agent, radar agent and command center agent, is established based on the studies of structure and function of BMDS. Considering the constraints brought by radar, intercept missile, offensive missile and commander, the objective function of DSS is established. In order to dynamically generate the optimal interception plan, the variable neighborhood negative selection particle swarm optimization (VNNSPSO) algorithm is proposed to support the decision making of DSS. The proposed algorithm is compared with the standard PSO, constriction factor PSO (CFPSO), inertia weight linear decrease PSO (LDPSO), variable neighborhood PSO (VNPSO) algorithm from the aspects of convergence rate, iteration number, average fitness value and standard deviation. The simulation results verify the efficiency of the proposed algorithm. The multi-agent DSS is developed through the Repast simulation platform and the constructed DSS can generate intercept plans automatically and support three-dimensional dynamic display of missile defense process.

关键词： agent-based modeling missile defense system decision support system (DSS) variable neighborhood negative selection particle swarm optimization (PSO)

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New chaos-based encryption scheme for digital sequence

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Journal of Systems Engineering and Electronics 2007年第4期18卷 698-703,709页

作者： Zhang Zhengwei fan Yangyu Zeng li School of Electronics and Information Northwestern Polytechnical Univ. Xi'an 710072 P. R. China

To enhance the anti-breaking performance of privacy information, this article proposes a new encryption method utilizing the leaping peculiarity of the periodic orbits of chaos systems. This method maps the secret sequence to several chaos periodic orbits, and a short sequence obtained by evolving the system parameters of the periodic orbits in another nonlinear system will be the key to reconstruct these periodic orbits. In the decryption end, the shadowing method of chaos trajectory based on the modified Newton-Raphson algorithm is adopted to restore these system parameters. Through deciding which orbit each pair coordinate falls on, the original digital sequence can be decrypted.

关键词： encryption scheme LPO (leaping periodic orbits) chaos initial conditions parameter estimation nonlinear system

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Providing Location-Aware Location Privacy Protection for Mobile Location-Based Services

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Tsinghua Science and Technology 2016年第3期21卷 243-259页

作者： Yu Wang Dingbang Xu fan li College of Information Engineering Taiyuan University of TechnologyTaiyuan 030024China Department of Computer Science the University of North Carolina at CharlotteCharlotteNC 28223USA Samsung Research America Mountain ViewCA 94043USA School of Computer Science Beijing Institute of TechnologyBeijing 100081China

Location privacy has been a serious concern for mobile users who use location-based services provided by third-party providers via mobile networks. Recently, there have been tremendous efforts on developing new anonymity or obfuscation techniques to protect location privacy of mobile users. Though effective in certain scenarios, these existing techniques usually assume that a user has a constant privacy requirement along spatial and/or temporal dimensions, which may be not true in real-life scenarios. In this paper, we introduce a new location privacy problem： Location-aware Location Privacy Protection （L2P2） problem, where users can define dynamic and diverse privacy requirements for different locations. The goal of the L2P2 problem is to find the smallest cloaking area for each location request so that diverse privacy requirements over spatial and/or temporal dimensions are satisfied for each user. In this paper, we formalize two versions of the L2P2 problem, and propose several efficient heuristics to provide such location-aware location privacy protection for mobile users. Through extensive simulations over large synthetic and real-life datasets, we confirm the effectiveness and efficiency of the proposed L2P2 algorithms.

关键词： location privacy k-anonymity cloaking algorithm location-based service mobile networks

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Analytical long-term evolution and perturbation compensation models for BeiDou MEO satellites

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Chinese Journal of Aeronautics 2018年第2期31卷 330-338页

作者： li fan Min HU Chao JIANG School of Aerospace Engineering Tsinghua University Beijing 100084 China Space Engineering University Beijing 101416 China College of Aerospace Science and Engineering National University of Defense Technology Changsha 410073 China

The current paper establishes the analytical models of the long-term evolution and perturbation compensation strategy for Medium Earth Orbits（MEO）shallow-resonant navigation constellation,with application to the Chinese Bei Dou Navigation Satellite System（BDS）.The long-term perturbation model for the relative motion is developed based on the Hamiltonian model,and the long-term evolution law is *** relationship between the control boundary of the constellation and the offset of the orbital elements is analyzed,and a general analytical method for calculating the offset of the orbit elements is *** analytical model is further improved when the luni-solar perturbations are *** long-term evolutions of the BDS MEO constellation within 10 years are illustrated,and the effectiveness of the proposed analytical perturbation compensation calculation approach is compared with the traditional numerical *** found the fundamental reason for the nonlinear variations of the relative longitude of ascending node and the mean argument of latitude is the long-periodic variations of the orbital inclination due to the luni-solar *** proposed analytical approach can avoid the numerical iterations,and reveal the essential relationship between the orbital element offsets and the secular drifts of the constellation ***,there is no need for maintaining the BDS MEO constellation within 10 years while using the perturbation compensation method.

关键词： BeiDou Navigation Satellite System (BDS) Long-term evolution Luni-solar perturbations Medium Earth Orbits(MEO) Perturbation compensation

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Phase-Sensitive Optical Time-Domain Reflectometry Amplified by Gated Raman Pump

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Photonic Sensors 2015年第4期5卷 345-350页

作者： Yi li Yi ZHOU li ZHANG Mengqiu fan Jin li Key Laboratory of Optical Fiber Sensing & Communications (Ministry of Education) University of Electronic Scienceand Technology of China Chengdu 611731 China

A long-range phase-sensitive optical time-domain reflectometry is proposed and experimentally demonstrated, based on the gated Raman amplification （RA）. This technique can reduce the amplified spontaneous emissions （ASE） noise of the Raman pump while extend the sensing distance. A direct-detection based phase-sensitive optical time-domain reflectometry （O-OTDR） with an operation range of 50 km and a spatial resolution of 20 m has been demonstrated. The influence of different delay time of the gated Raman pump on the O-OTDR system is also discussed.

关键词： Fiber optic sensors Rayleigh scattering stimulated Raman scattering

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Rhinogobius immaculatus, a new species of freshwater goby (Teleostei Gobiidae) from the Qiantang River, China

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Zoological Research 2018年第6期39卷 396-405页

作者： fan li Shan li Jia-Kuan Chen Institute of Biodiversity Science Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Fudan UniversityShanghai 200433 China Shanghai Ocean University Shanghai 200090 China Shanghai Natural History Museum Branch of Shanghai Science & Technology Museum Shanghai 200041 China

A new freshwater goby, Rhinogobius immaculatus sp. nov., is described here from the Qiantang River in China. It is distinguished from all congeners by the following combination of characters： second dorsal-fin rays I, 7-9; anal-fin rays I, 6-8; pectoral-fin rays 14-15; longitudinal scales 29-31; transverse scales 7-9; predorsal scales 2-5; vertebrae 27 （rarely 28）; preopercular canal absent or with two pores; a red oblique stripe below eye in males; branchiostegal membrane mostly reddish-orange, with 3-6 irregular discrete or connected red blotches on posterior branchiostegal membrane and lower operculum in males; caudal-fin base with a median black spot; and no black blotch on anterior part of first dorsal fin in males.

关键词： Gobiidae Rhinogobius New species Qiantang River China

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 16-21页

作者： YANG fan li Dao-ben School of Information Engineering Beijing University of Posts andTelecommunications Beijing 100876 China

A more accurate correlated multiple input and multiple output （MIMO） channel model for IEEE 802.16n is presented. On one hand, this MIMO channel model can obtain more precise antenna correlation, which is a key character for MIMO channel and important for the research of IEEE 802.16n and MIMO technologies. On the other hand, it maintains a low complexity of simulation.

关键词： MIMO channel model power delay profile antenna correlation

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How two helicases work together within the TFIIH complex, a perspective from structural studies of XPB and XPD helicases

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Frontiers in Biology 2013年第4期8卷 363-368页

作者： li fan Department of Biochemistry University of California at Riverside Riverside CA 92521 USA

Xeroderma pigmentosum group B （XPB） and D （XPD） are two DNA helicases inside the transcription factor TFIIH complex required for both transcription and DNA repair. The importance of these helicases is underscored by the fact that mutations of XPB and XPD cause diseases with extremely high sensitivity to UV-light and high risk of cancer, premature aging, etc. This mini-review focuses on recent developments in both structural and functional characterization of these XP heficases to illustrate their distinguished biological roles within the architectural restriction of the TFIIH complex. In particular, molecular mechanisms of DNA unwinding by these helicases for promoter opening during transcription initiation and bubble-creation around the lesion during DNA repair are described based on the integration of the crystal structures of XPB and XPD helicases into the architecture of the TFIIH complex.

关键词： XPB XPD TFIIH helicase DNA repair nucleotide excision repair Wanscription

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BL Lacertae objects and the extragalactic γ-ray background

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Research in Astronomy and Astrophysics 2011年第8期11卷 879-887页

作者： fan li Xin-Wu Cao Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

A tight correlation between γ-ray and radio emission is found for a sample of BL Lacertae （BL Lac） objects detected by the Fermi Gamma-ray Space Telescope （Fermi） and the Energetic Gamma-Ray Experiment Telescope （EGRET）. The γ-ray emission of BL Lac objects exhibits strong variability, and the detection rate of γ-ray BL Lac objects is low, which may be related to the γ-ray duty cycle of BL Lac objects. We estimate the γ-ray duty cycle, δγ ≌ 0.11, for BL Lac objects detected by EGRET and Fermi. Using the empirical relation of γ-ray emission with radio emission and the estimated γ-ray duty cycle δγ, we derive the γ-ray luminosity function （LF） of BL Lac objects from their radio LE Our derived γ-ray LF of BL Lac objects can almost reproduce that calculated with the recently released Fermi bright active galactic nuclei （AGN） sample. Comparison of the derived LF of the γ-ray BL Lac objects in this work with that derived by Abdo et al. （2009a） requires the γ-ray duty cycle of BL Lac objects to be almost luminosity-independent. We find that - 45% of the extragalactic diffuse γ-ray background （EGRB） is contributed by BL Lac objects. Combining the estimate of the quasar contribution to the EGRB in the previous work, we find that 77% of the EGRB is contributed by BL Lac objects and radio quasars.

关键词： galaxies active -- galaxies BL Lacertae objects general -- cosmology diffuse radiation -- gamma rays theory

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Screening of Amaranth Cultivars(Amaranthus mangostanus L.) for Cadmium Hyperaccumulation

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Agricultural Sciences in China 2009年第3期8卷 342-351页

作者： fan Hong-li ZHOU Wei Key Laboratory of Crop Nutrition and Fertilization Ministry of Agriculture~Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences Beijing 100081 P.R. China

The potential harm of soil cadmium pollution to ecological environment and human health has been increasingly widely concerned. Phytoremediation, as a kind of new and effective technology, has become an important method for cleaning up cadmium in contaminated sites. The amaranth （Amaranthus mangostanus L.） is widely distributed and has abundant varieties in China, its rapid growth and large biomass can be served as candidate for cadmium hyperaccumulators for phytoremediation. To obtain cadmium hyper-accumulator, Cd uptake in 23 amaranth cultivars from different ecological region was investigated under hydroponic culture condition. Meanwhile, pot experiment was established to probe phytoremediation potentiality of Cd contaminated soil by amaranth. Three treatment （Cd 5, 10, and 25 mg kg^-1） were imposed to red soil, yellow brown soil, and vegetable soil. The results showed that under hydroponic culture with Cd 3 mg L^-1, the cadmium concentration in the shoots of the cultivar Tianxingmi reached 260 mg kg^-1, and its total cadmium uptake was the highest among various cultivars. In the treatment Cd 25 mg kg^-1, the cadmium concentration in the shoots of the cultivar Tianxingmi reached 212 mg kg^-1, while bioaccumulation factor and shoot purification rate reached 8.50 and 3.8%, respectively. Further, the total biomass and shoot biomass were not decreased significantly under Cd exposure. These results suggested that cultivar Tianxingmi is a typical Cd hyperaccumulator, and can be expected to be used in phytoremediation of Cd contaminated soil.

关键词： cadmium hyperaccumulation amaranth phytoremediation

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