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OPTIMAL TARGET TRAJECTORY ESTIMATION AND FILTERING USING NETWORKED SENSORS

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Journal of Systems Science & Complexity 2008年第3期21卷 325-336页

作者： Jiangping hu Xiaoming hu Optimization and Systems Theory and ACCESS Linnaeus Center Royal Institute of Technology Stockholm 10044 Sweden

Target tracking using distributed sensor network is in general a challenging problem because it always needs to deal with real-time processing of noisy information. In this paper the problem of using nonlinear sensors such as distance and direction sensors for estimating a moving target is studied. The problem is formulated as a prudent design of nonlinear filters for a linear system subject to noisy nonlinear measurements and partially unknown input, which is generated by an exogenous system. In the worst case where the input is completely unknown, the exogenous dynamics is reduced to the random walk model. It can be shown that the nonlinear filter will have optimal convergence if the number of the sensors are large enough and the convergence rate will be highly improved if the sensors are deployed appropriately. This actually raises an interesting issue on active sensing： how to optimally move the sensors if they are considered as mobile multi-agent systems？ Finally, a simulation example is given to illustrate and validate the construction of our filter.

关键词： Optimal filter sensor network target tracking

Sequential use of ultraviolet light and chlorine for reclaimed water disinfection

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Journal of Environmental Sciences 2011年第10期23卷 1605-1610页

作者： Xiujuan Wang Xuexiang hu Chun hu Dongbin Wei State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Several disinfection processes of ultraviolet （UV）, chlorine or UV followed by chlorine were investigated in municipal wastewater according to the inactivation of Escherichia coli, Shigella dysenteriae and toxicity formation. The UV inactivation of the tested pathogenic bacteria was not affected by the quality of water. It was found that the inactivated bacteria were obviously reactivated after one day in dark. Fluorescent light irradiation increased the bacteria repair. The increase of UV dosage could cause more damage to bacteria to inhibit bacteria self-repair. No photoreactivation was detected when the UV dose was up to 80 mJ/cm2 for E. coli DH5ct, and 23 mJ/cm2 for S. dysenteriae. Nevertheless, sequential use of 8 mJ/cm2 of UV and low concentration of chlorine （1.5 mg/L） could effectively inhibit the photoreactivation and inactivate E. coli below the detection limits within seven days. Compared to chlorination alone, the sequential disinfection decreased the genotoxicity of treated wastewater, especially for the sample with high NH3-N concentration.

关键词： chlorine disinfection sequential disinfection UV disinfection photoreactivation genotoxicity wastewater reclamation

Rough Set Model for Cognitive Expectation Embedded Interval-Valued Decision Systems

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Chinese Journal of Electronics 2018年第4期27卷 675-679页

作者： DAI Jianhua LIU Zhenbo hu hu SHI Hong School of Computer Science and Technology Tianjin University College of Computer Science and Technology Zhejiang University

Interval-valued information system is a kind of knowledge representation model for uncertain information. An interval-valued attribute has an expectation by experience or background knowledge, called cognitive expectation. There are few studies aiming at intervalvalued attributes with cognitive expectations. We propose the concept of Interval-valued decision system with expectations(IDSE). A new dominance relation based on the distances between expectations and interval values is constructed. Based on the constructed dominance relation, a rough set model for IDSE is investigated. Attribute reduction in IDSE is also examined by using discernibility matrices and discernibility functions.

关键词： Rough set Interval-valued decision system with cognitive expectation Attribute reduction

Influence of substrate metals on the crystal growth of AlN films

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International Journal of Minerals,Metallurgy and Materials 2010年第1期17卷 98-103页

作者： Juan Xiong Hao-shuang Gu Kuan hu Ming-zhe hu School of Physics and Electronic Technology Hubei University Wuhan 430062 China

AlN films were deposited by reactive radio frequency （RF） sputtering on various bottom electrodes, such as Al, Ti, Mo, Au/Ti, and Pt/Ti. The effects of substrate metals on the orientation of AlN thin films were investigated. The results of X-ray diffraction, atomic force microscopy, and field emission scanning electron microscopy show that the orientation of AlN films depends on the kinds of substrate metals evidently. The differences of AlN films deposited on various metal electrodes are attributed to the differences in lattice mismatch and thermal expansion coefficient between the AlN material and substrate metals. The AlN film deposited on the Pt/Ti electrode reveals highly the c-axis orientation with well-textured columnar structure. The positive role of the Pt/Ti electrode in achieving the high-quality AlN films and high-performance film bulk acoustic resonator （FBAR） may be attributed to the smaller lattice mismatch as well as the similarity of thermal expansion coefficient between the deposited AlN material and the Pt/Ti electrode substrate.

关键词： AlN films substrate orientation crystallinity

Attribute reduction in interval-valued information systems based on information entropies

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Frontiers of Information Technology & Electronic Engineering 2016年第9期17卷 919-928页

作者： Jian-hua DAI hu hu Guo-jie ZHENG Qing-hua hu hui-feng HAN Hong SHI School of Computer Science and Technology Tianjin University College of Computer Science and Technology Zhejiang University

Interval-valued data appear as a way to represent the uncertainty affecting the observed values. Dealing with interval-valued information systems is helpful to generalize the applications of rough set theory. Attribute reduction is a key issue in analysis of interval-valued data. Existing attribute reduction methods for single-valued data are unsuitable for interval-valued data. So far, there have been few studies on attribute reduction methods for interval-valued data. In this paper, we propose a framework for attribute reduction in interval-valued data from the viewpoint of information theory. Some information theory concepts, including entropy, conditional entropy, and joint entropy, are given in interval-valued information systems. Based on these concepts, we provide an information theory view for attribute reduction in interval-valued information systems. Consequently, attribute reduction algorithms are proposed. Experiments show that the proposed framework is effective for attribute reduction in interval-valued information systems.

关键词： Rough set theory Interval-valued data Attribute reduction Entropy

Numerical and Experimental Study on Contact Face and Shock Wave Motion in the Receiving Tube of Gas Wave Refrigerator

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Journal of Thermal Science 2006年第4期15卷 337-341页

作者： Dapeng hu Shengtao CHEN hu LIU Zuzhi CHEN Che Zhu Institute of Chemical Engineering Dalian University of Technology Dalian Liaoning China

The contact face and shock wave motion in an open ends receiving tube of gas wave refrigerator are investigated numerically and experimentally. The results show that, velocity of the contact face rises rapidly as gas is injected into the receiving tube, and drops sharply after a steady propagation. However, velocity of the shock wave in the tube is almost linear. With increasing of inlet pressure, velocity of the shock wave and steady velocity of contact face also increase. In addition, time and distance of contact face propagation in the receiving tube become longer.

关键词： contact face shock wave receiving tube gas wave refrigerator

Experiment on building a real-time temperature field distribution model of the prostate using special data encryption multi-pole radiofrequency ablation and a visualization phantom

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Chinese Science Bulletin 2011年第35期56卷 3845-3853页

作者： CHEN Lei hu Bing hu Bin Department of Ultrasound Affiliated Sixth People ＂s Hospital Shanghai Jiaotong University Shanghai 200233 China

The aim of this study was to explore the utility of a visualization phantom for building a real-time temperature field distribution model of the prostate created by the application of special data encryption(SDE) multi-pole radiofrequency(RF) *** prepared phantoms(phantom group) using acrylamide as the raw material and egg-white as a color developing *** prostate specimens of male adult dogs were fixed in this phantom to create a prostate phantom(prostate group).The SDE multi-pole RF electrode was inserted into the two groups for RF ablation,and the temperature changes at relevant points in space were *** set the x-axis as the left and right direction,the y-axis as the fore and aft direction,and the z-axis as the insertion direction of the RF *** this process,the effect of RF ablation on the appearance of each of the two groups was *** temperature measurements taken during the operation,a three-dimensional(3D) surface model of temperature was constructed by drawing the boundary areas of different temperatures on the maximum x-z plane of the two groups of ablation lesions,with y equivalent to *** comparison of the temperature-time change curves of four space points were made by setting y equivalent to 0,z equivalent to 0.5,and x equivalent to 0,0.25,0.5 and *** solid lesions with a diameter of approximately 12 mm could be found in both groups after RF *** the ablation of the phantom group,the temperature ascended faster in a zone 1 cm from the needlepoint to the needle body,and 0.5 cm about the radiofrequency *** time-property result of the x-z plane with y equivalent to 0 showed that the boundary areas of the two groups were closer at 50 and 60°C,but the difference between the two groups at 70°C in the high temperature zone was relatively *** 3D temperature surface model further proved that the 3D temperature outline at 60°C was in better concordance with the actual effect of RF abl

关键词：温度场分布射频消融前列腺癌数据加密分布模型临床试验可视化多极

Current neutralization and plasma polarization for intense ion beams propagating through magnetized background plasmas in a two-dimensional slab approximation

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Frontiers of physics 2014年第2期9卷 226-233页

作者： Zhang-hu hu Mao-Du Chen You-Nian Wang School of Physics and Optoeleetronic Technology Dalian University of Technology Dalian 116024 China

A two-dimensional electromagnetic Particle-in-Cell （PIC） simulation model is proposed to study the propagation of intense, ion beams with beaIn width wb small compared to the electron skin depth c/wpe through background plaslnas in tile presence of external applied magnetic fields. The effcctive eleetron gyrora,dius wge is found to be an important parameter for ion beam transport in the presence of magnetic fields,In the bealn regions, the background plasmas respond differently to the ion beanl of width wb〈wge and wb 〉 wge for the given magnetic field and beaan encrgy, For the case of beam width wb 〈 wge with relative weak external magnetic fiehts, the rotalion effects of plasma electrons a,re found to be signifieant and contributes to the signitica,nt enilaneeinent of the self electric and seif-magnetic fields. While for the ease of beam width wb 〉 wge with relative strong external magnetic fields, the rotation effects of plasma cleetrons are strongly inhibited and a, well neutraliza, tion of ion beam current can be found. Finally, the influences of diftiuent beam widths. beam energies and magnetic fields on the neutralization of ion bc, anl eurrellt are summarized for the eases of wb 〈 wge〈 c/wpe,wge 〈wb〈c/wbp and wb〈c/wpe〈wge.

关键词： current neutralization ion beams magnetized plasmas Particle-in-Cell simulations

Solution of the Energy Level of Hydrogen-Like Atom for the Debye Shielding Potential

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Communications in Theoretical Physics 2002年第5期38卷 601-605页

作者： hu Xian-Quan hu Wen-Jiang MA Yong Department of Physics Chongqing Normal University Chongqing 400047 China Department of Electronic Information Engineering Chongqing University of Post and Telecommunications Chongqing 400065 China Department of Physics Chongqing Normal University Chongqing 400047 China

The first-order revision and the approximation analytical formula of the energy levels for hydrogen-likeatoms under the condition of Debye shielding potential are achieved by means of the Rayleigh-Schrodinger perturbationtheory; meanwhile, the corresponding recurrence relations are obtained from the use of the solution of power series. Basedon the above solutions and with the use of energy consistent method the equivalent value of second-order reversion underthe condition of Debye shielding potential is produced as well and the result is compared with the data obtained by thenumerical method. Besides, the critical bond-state and corresponding cut-off conditions are discussed.

关键词： Debye potential, recurrence relations, energy consistent method, hydrogen-like atoms, criticalbond-state