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Optimality Analysis of Sensor-Target Geometries for Bearing-Only Passive Localization in Three Dimensional Space

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Chinese Journal of Electronics 2016年第2期25卷 391-396页

作者： ZHONG Yu wu Xiaoyan HUANG Shucai LI Chengjing wu jianfeng Air and Missile Defense College Air Force Engineering University

Optimality analysis of sensor to target observation geometry for bearing-only passive localization is of practical significance in engineering and military applications and this paper generalized predecessors' researches in two-dimensions into three dimensional space. Based on the principles of Cramer-Rao lower bound(CRLB), Fisher information matrix(FIM) and the determinant of FIM derived by Cauchy-Binet formula, this paper configured the optimal observation geometry resulted from maximizing the determinant of FIM. Optimal observation geometry theorems and corresponding propositions were proved for N ≥ 2 sensors in three dimensions. One conjecture was proposed, i.e., when each range of N(N ≥ 4) sensors to the single target is identical, configuring the optimal geometry is equivalent to distributing N points uniformly on a unit sphere, which is one of the worldwide difficult problem. Studies in this paper can provide helpful reference for passive sensor deployment, route planning of detection platform and so on.

关键词： Bearing-only passive localization Optimal observation geometry Cramer-Rao lower bound(CRLB) Fisher information matrix(FIM) Distributing uniformly points on a Sphere conjecture

Nucleate pool boiling heat transfer measurements of HFC23/CFC13 system

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Journal of Thermal Science 2007年第4期16卷 370-375页

作者： Liqiang ZHANG Maoqiong GONG jianfeng wu Lie XU Institute of Refrigeration and Cryogenics Shanghai Jiao Tong University Shanghai 200030 China Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China

Nucleate pool boiling heat transfer data of the HFC23/CFC13 system have been systematically measured in a wide range of pressures and heat fluxes. The experimental results are also compared with the measured data of R508A and R508B. It is found that the heat transfer coefficient of R503 （HFC23/CFC13=0.511/0.489） is higher than that of R508A and R508B. Furthermore, the measured data were compared with the predicted results with three well-known correlations. Correlation by Fujita and Tsutsui can provide acceptable results. Most of the data fall within ±20% of this correlation.

关键词： heat transfer pool boiling azeotropic system refrigerant mixtures.

Process Optimization for Cerium Oxide Based Conversion Coating of AZ91D Magnesium Alloy at Room Temperature

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稀有金属材料与工程 2012年第S1期41卷 243-246页

作者： Chen Dongchu wu jianfeng Ye Shulin Foshan Univ Sch Sci Foshan 528000 Peoples R China

The Ce2SO4/H2O2 containing solution is used to prepare a chrome-free cerium oxide based chemical conversion coating on AZ91D magnesium alloy at room temperature,and an orthogonal experiment was carried out to optimize the treating *** effect of preparing parameters on the coating growth and the corrosion resistance were *** was found that H2O2 is the dominant influence factor on the coating weight gain in the orthogonal experiment,with Ce(SO4)2 coming next and immersion time having the least impact,while the most dominant influence factor on the corrosion resistance is Ce(SO4)2,with H2O2 coming next and immersion time having the least *** coating has the best corrosion resistance,treated in the solution of 10 g/l Ce(SO4)2 and 12 ml/l H2O2 for 4 *** was adopted to study the micro-morphology of the conversion coating on magnesium alloy surface The prolonged immersion time duration or the increased concentration of Ce(SO4)2 and H2O2 will increase the coating thickness,but tiny cracks appears resulted from the fast coating deposition.

关键词： magnesium alloy cerium conversion coating chrome-free room temperature

Comparison of dilution effects of R134a and nitrogen on flammable hydrofluorocarbons

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Journal of Thermal Science 2009年第4期18卷 377-381页

作者： Zhenming Li Maoqiong Gong jianfeng wu Yuan Zhou Key Laboratory of Cryogenics Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing100190 China Graduate University of the Chinese Academy of Sciences Beijing 100039 China

An experimental apparatus has been built to measure the flammability limits of combustible gases based on Chinesenational standard GB/T 12474-90. The flammability limits of four binary mixtures of R161/R134a,R152a/R134a, R161/N2 and R152a/N2 were measured with this apparatus at atmospheric pressure and ambienttemperature. The fuel inertization points (FIP) of these mixtures can be found from the envelopes. Comparisonswere made with the literature data; good agreement for most measurements was obtained. R134a was found tohave a better dilution effect than nitrogen in reducing the flammability of hydrofluorocarbons.

关键词： Flammability limits fuel inertization point dilution effect

A Hybrid Multi-Objective Evolutionary Algorithm for Optimal Groundwater Management under Variable Density Conditions

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Acta Geologica Sinica(English Edition) 2012年第1期86卷 246-255页

作者： YANG Yun wu jianfeng SUN Xiaomin LIN Jin wu Jichun Department of Hydrosciences School of Earth Sciences and EngineeringNanjing UniversityNanjingJiangsu 210093China Nanfing Hydraulic Research Institute NanjingJiangsu 210029China

In this paper, a new hybrid multi-objective evolutionary algorithm （MOEA）, the niched Pareto tabu search combined with a genetic algorithm （NPTSGA）, is proposed for the management of groundwater resources under variable density conditions. Relatively few MOEAs can possess global search ability contenting with intensified search in a local area. Moreover, the overall searching ability of tabu search （TS） based MOEAs is very sensitive to the neighborhood step size. The NPTSGA is developed on the thought of integrating the genetic algorithm （GA） with a TS based MOEA, the niched Pareto tabu search （NPTS）, which helps to alleviate both of the above difficulties. Here, the global search ability of the NPTS is improved by the diversification of candidate solutions arising from the evolving genetic algorithm population. Furthermore, the proposed methodology coupled with a density-dependent groundwater flow and solute transport simulator, SEAWAT, is developed and its performance is evaluated through a synthetic seawater intrusion management problem. Optimization results indicate that the NPTSGA offers a tradeoff between the two conflicting objectives. A key conclusion of this study is that the NPTSGA keeps the balance between the intensification of nondomination and the diversification of near Pareto-optimal solutions along the tradeoff curves and is a stable and robust method for implementing the multi-objective design of variable-density groundwater resources.

关键词： seawater intrusion multi-objective optimization niched Pareto tabu search combined with genetic algorithm niched Pareto tabu search genetic algorithm

A Study on the Ore-forming Effect of Mantle-derived Fluid

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Petroleum Science 2007年第4期4卷 44-49页

作者： Meng Qingqiang wu jianfeng Zhang Liuping Basin and Reservoir Research Center China University of Petroleum Beijing 102249 China） Key Laboratory of Hydrocarbon Migration and Accumulation Ministry of Education China University of Petroleum Beijing 102249 China Beijing Tianyi United Investment and Management Co. Ltd. Beijing 100013 China Institute of Geology and Geophysics China Academy of Science Beijing 100029 China

Based on summarizing of the effect of mantle-derived fluid on the formation of ores, especially on gold ore, and with the latest investigations, such as the formation of ore from the action of shallow-deep fluid, the transportation effect of the thermal energy by mantle-derived fluid, this paper mainly aims at the effect of mantle-derived fluid on the generation of hydrocarbons. With the proof from geochemistry and fluid inclusion, it was suggested that the mantle-derived fluid not only supplied source materials for hydrocarbons, but also supplied essential energy and matter necessary for the generation of hydrocarbons. The mantle-derived fluid had a good effect, but at the same time it had an adverse effect under specific conditions, on the formation of reservoirs. This paper also discusses the future direction and significance of studying mantle-derived fluid.

关键词： Mantle-derived fluid ore-forming effect mantle ore oil and gas accumulation

Determination of trace heavy metals in milk using an ionic liquid and bismuth oxide nanoparticles modified carbon paste electrode

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Chinese Science Bulletin 2012年第15期57卷 1781-1787页

作者： PING jianfeng wu Jian YING YiBin College of Biosystems Engineering and Food Science Zhejiang University Hangzhou 310058 China

A novel carbon composite electrode modified with bismuth oxide nanoparticles and the ionic liquid n-octylpyridinium hexafluorophosphate was fabricated and used to simultaneously determine cadmium and lead levels using square wave anodic stripping *** electrode combines the unique advantages of nanomaterials and ionic liquid with the low cost and easy fabrication of the carbon composite *** with the traditional binder based composite electrode,our electrode exhibited well-defined and separate stripping voltammetric peaks for cadmium and ***,the antifouling capacity of the bismuth film electrode was significantly improved by the ionic *** optimized conditions,the linear range of the composite electrode was from 3.0 to 30.0 μg L-1 for both metal ions with a detection limit of 0.15 μg L-1 for cadmium and 0.21 μg L-1 for *** milk sample analyses showed that the modified electrode was sensitive,reliable and effective for the determination of trace heavy metals,holding great promise for routine analysis applications.

关键词：修饰碳糊电极微量重金属离子液体同时测定纳米粒子牛奶样品氧化铋碳纤维复合材料

CO_2 solubility in aqueous solutions of N-methyldiethanolamine+piperazine by electrolyte NRTL model

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Science China Chemistry 2016年第3期59卷 360-369页

作者： Jicai Huang Maoqiong Gong Xueqiang Dong Xiaodong Li jianfeng wu Technical Institute of Physics and Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences School of Energy and Power Engineering Beihang University

Accurate modeling of the solubility behavior of CO_2 in the aqueous alkanolamine solutions is important to design and optimization of equipment and process. In this work, the thermodynamics of CO_2 in aqueous solution of N-methyldiethanolamine(MDEA) and piperazine(PZ) is studied by the electrolyte non-random two liquids(NRTL) model. The chemical equilibrium constants are calculated from the free Gibbs energy of formation, and the Henry's constants of CO_2 in MDEA and PZ are regressed to revise the value in the pure water. New experimental data from literatures are added to the regression process. Therefore, this model should provide a comprehensive thermodynamic representation for the quaternary system with broader ranges and more accurate predictions than previous work. Model results are compared to the experimental vapor-liquid equilibrium(VLE), speciation and heat of absorption data, which show that the model can predict the experimental data with reasonable accuracy.

关键词： N-methyldiethanolamine piperazine carbon dioxide electrolyte NRTL

Nucleate Pool Boiling Heat Transfer of Pure Refrigerants and Binary Mixtures

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Journal of Thermal Science 2004年第3期13卷 259-263页

作者： Zhaofu SUN Maoqiong GONG Yanfeng QI Zhijian LI jianfeng wu Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing100080China Graduate School of the Chinese Academy of Sciences Beijing100039China

Heat transfer coefficients in nucleate boiling on a smooth flat surface were measured for pure fluids of R-134a, propane, isobutane and their binary mixtures at different pressure from 0.1 to 0.6 MPa. Series of experiments with different heat flux and mixture concentrations were carried out. The influences of pressure and heat flux on the heat transfer coefficient for different pure fluids were studied. Isobutane and propane were used to make up binary mixtures. Compared to the pure components, binary mixtures show lower heat transfer coefficients. This reduction was more pronounced as the heat flux increasing. Several heat transfer correlations are obtained for different pure refrigerants and their binary mixtures.

关键词： heat transfer pool boiling binary mixtures.