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Error analysis of the semi-discrete local discontinuous Galerkin method for semiconductor device simulation models

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science china mathematics 2010年第12期53卷 3255-3278页

作者： LIU YunXian 1, & SHU Chi-Wang 2 1 School of mathematics, Shandong university, Jinan 250100, china 2 Division of Applied mathematics, Brown university, Providence, RI 02912, USA School of mathematics Shandong University Jinan China Division of Applied mathematics Brown University Providence USA

In this paper we continue our effort in Liu-Shu (2004) and Liu-Shu (2007) for developing local discontinuous Galerkin (LDG) finite element methods to discretize moment models in semiconductor device simulations. We consider drift-diffusion (DD) and high-field (HF) models of one-dimensional devices, which involve not only first derivative convection terms but also second derivative diffusion terms, as well as a coupled Poisson potential equation. Error estimates are obtained for both models with smooth solutions. The main technical difficulties in the analysis include the treatment of the inter-element jump terms which arise from the discontinuous nature of the numerical method, the nonlinearity, and the coupling of the models. A simulation is also performed to validate the analysis.

关键词： local discontinuous Galerkin method error estimate semiconductor

New development thoughts on the bio-inspired intelligence based control for unmanned combat aerial vehicle

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science china(Technological sciences) 2010年第8期53卷 2025-2031页

作者： DUAN HaiBin 1 ,SHAO Shan 2 ,SU BingWei 3.&ZHANG Lei 41 State Key Laboratory of science and technology on Holistic Flight Control,School of Automation science and Electrical Engineering, Beijing {3. of Aeronautics and Astronautics,Beijing 100191,china 2 Flight Control Department,Shenyang Aircraft Design and Research Institute,Shenyang 11003.,china 3.Beijing Institute of Near Space Vehicle’s System Engineering,Beijing 100076,china 4Integration and Project Section,Air Force Equipment Academy,Beijing 100085,china State Key Laboratory of science and technology on Holistic Flight Control School of Automation Science and Electrical Engineering Beijing University of Aeronautics and Astronautics Beijing China Flight Control Department Shenyang Aircraft Design and Research Institute Shenyang China Beijing Institute of Near Space Vehicle’s System Engineering Beijing China Integration and Project Section Air Force Equipment Academy Beijing China

Bio-inspired intelligence is in the spotlight in the field of international artificial intelligence,and unmanned combat aerial vehicle(UCAV),owing to its potential to perform dangerous,repetitive tasks in remote and hazardous,is very promising for the technological leadership of the nation and essential for improving the security of *** the basis of introduction of bioinspired intelligence and UCAV,a series of new development thoughts on UCAV control are proposed,including artificial brain based high-level autonomous control for UCAV,swarm intelligence based cooperative control for multiple UCAVs,hy-brid swarm intelligence and Bayesian network based situation assessment under complicated combating environments, bio-inspired hardware based high-level autonomous control for UCAV,and meta-heuristic intelligence based heterogeneous cooperative control for multiple UCAVs and unmanned combat ground vehicles(UCGVs).The exact realization of the proposed new development thoughts can enhance the effectiveness of combat,while provide a series of novel breakthroughs for the intelligence,integration and advancement of future UCAV systems.

关键词： bio-inspired intelligence unmanned combat aerial vehicle(UCAV) artificial brain autonomous control bayesian network bio-inspired hardware heterogeneous cooperative control

DSC　STUDY　OF　MARTENSITIC　TRANSFORMATION　KINETICS　IN　A　Cu－Zn－Al－Mn－Ni　SHAPE　MEMORY　ALLOY

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Acta Metallurgica Sinica(English Letters) 1996年第1期9卷 56-58页

作者： GENG Guili BAI Yujun PENG Qifeng(Institute for Materials Engineering,Shandong university of technology,Jinan 250014,china) Shandong Univ of technology Jinan China

The kinetics of the reversible martensitic transformation in a Cu-Zn-Al-Mn-Ni shape memory alloy has been studied by means of differential scanning *** apparent activation energy has been calculated and the kinetic equations of positive and adverse martensitic transformation have been established with the variations of temperature and time.

关键词： shape memory alloy positive and adverse martensitic transformation phase transformation kinetics DSC study

STUDY ON THE MORPHOLOGY OF POLYVINYL CHLORIDE/POLYSTYRENE BLENDS BY ELECTRON MICROPROBE ANALYSIS

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Chinese Journal of Polymer science 2000年第5期18卷 437-441页

作者： Zheng-ping Fang Gen-lin Wang Guo-ping Cai Cheng-wei Xu Jie Qian Institute of Polymer Composites, Zhejiang university, Hangzhou 3.0027, china College of Chemical Engineering, Zhejiang university of {3., Hangzhou 3.0014, china 浙江大学浙江杭州浙江工业大学浙江杭州

The morphology of polyvinyl chloride/polystyrene (PVC/PS) blend samples with different mass ratios, prepared by means of solution casting and melt mixing, have been successfully examined by electron microprobe analysis (EMP). This experiment was performed in a scanning electron microscope attached to an energy dispersive X-ray analyzer. Differential scanning calorimetry was also used to investigate the phase separation of the blends. The results show that PVC and PS are incompatible and the blends have sea-islands phase structures. Blends prepared via melt mixing have finer phase-dispersion than those prepared via solution casting.

关键词： electron microprobe analysis polyvinyl chloride/polystyrene blends morphology

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一类流域点污染源识别的稳定性与数值模拟

水动力学研究与进展（A辑） 2008年第4期23卷 364-371页

作者：王泽文邱淑芳核资源与环境教育部重点实验室(东华理工大学) 江西南昌330013 东华理工大学数学与信息科学学院

本文考虑了流域中单个点污染源识别问题的唯一性、稳定性和反演算法。该问题的数学模型为一维线性对流反应扩散方程,方程的源项F(x,t)表示了污染源是一个随时间变化的点污染源。在对污染源及测量点的先验假设下,获得了点源识别的唯一性... 详细信息

本文考虑了流域中单个点污染源识别问题的唯一性、稳定性和反演算法。该问题的数学模型为一维线性对流反应扩散方程,方程的源项F(x,t)表示了污染源是一个随时间变化的点污染源。在对污染源及测量点的先验假设下,获得了点源识别的唯一性和局部稳定性,给出了识别污染源位置s和污染强度λ(t)的计算方法。数值例子表明源项反演的算法是有效的。

关键词：源项识别对流反应扩散方程局部稳定性反问题水污染

Genomics,metagenomics,and microbial oceanography—A sea of opportunities

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science china Earth sciences 2011年第4期54卷 473-480页

作者： FANG JiaSong 1,2 &ZHANG Li 3.1 State Key Laboratory of Marine Geology,Tongji university,Shanghai 200092,china 2 College of Natural and Computational sciences,Hawaii Pacific university,Kaneohe,HI 96744,USA 3.tate Key Laboratory of Geological Processes and Mineral Resources,Faculty of Earth sciences,china university of Geosciences,Wuhan 43.074,china State Key Laboratory of Marine Geology Tongji University Shanghai China College of Natural and Computational sciences Hawaii Pacific University Kaneohe USA State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Sciences China University of Geosciences Wuhan China

Microbial oceanography is an emerging discipline resulted from the interaction,cross-fertilization and integration of life science and ocean *** oceanography integrates the principles of marine microbiology,microbial ecology and oceanography to study the role of microorganisms in the biogeochemical dynamics of natural marine *** application of genomics tools to study marine microbes is resulting in rapid advancements in microbial oceanography that has important implications in global carbon cycle,climate change,and ecosystem *** we review the application of genomics and metagenomics in microbial oceanography and suggest future directions in microbial oceanography research.

关键词： microbial oceanography genomics metagenomics genes biomass bacteria archaea eukarya phylogeny physiology metabolism ecology biogeochemistry microbiology ecosystem function

Atmospheric nitrous oxide observations above the oceanic surface during chinaRE-18

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Progress in Natural science:Materials International 2003年第8期 57-61页

作者： ZHU Renbin, SUN Liguang and LIU Xiaodong(Institute of Polar Environment, university of science and technology of china, hefei 23.026, china) Institute of Polar Environment University of Science and Technology of China Hefei 230026 China

The gas samples in the marine boundary layer were collected from the track for research ship Xuelong during the 18thChinese Antarctic Research Expedition (chinaRE-18) and nitrous oxide measurements were made by HP5890ECD-GC in the laborato-ry. The results represent the shipboard N2O data set obtained within the lower troposphere with the average concentration of (3.3.5±2.6 ) nL· L-1from 3.°N to 69°S. The results showed a latitudinally weighted, mean interhemispheric difference of 0.61 nL·L-1. Thelatitudinal distribution of atmospheric N2O concentration was analyzed from northern midlatitudes to Southern Ocean around the Antarcticcontinent and it was showed that N2O concentration in the current confluences was higher than that in other oceanic areas. This indicatedthat strong N2O emissions occurred there. The longitudinal distribution of N2O concentrations in the Southern Ocean also showed similarsituation. According to the interhemispheric difference of atmospheric N2O concentrations

关键词： Antarctica the Pacific Ocean nitrous oxide vacuum vial.

Study of a Novel Rotary Cyclone Gas-Solid Separator

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Journal of Thermal science 2003年第3期12卷 275-278,282页

作者： Zhiguang Ling Xingyong DengResearch Institute of Energy and Environmental Engineering, Shanghai university of Engineering science, 2003.6, Shanghai, china Research Institute of Energy and Environmental Engineering Shanghai University of Engineering Science Shanghai China

Based on the analytical study of the characteristics of fine particle motion in swirling flow, a new design idea on flow organization and construction aimed at increasing the positive radial flow in the separation chamber of the rotary cyclone separator (PRV type) was proposed. Experimental verification including the test of variation of separation efficiency and pressure loss with the first and secondary flow ratio show that this new type separator has higher and more stable separation efficiency in broad flow ratio range while the pressure loss is far below the conventional rotary cyclone separator and even comparable with that of simple cyclone separator.

关键词： gas-solid separation rotary cyclone separator flows in cyclones

EFFECT OF MICROSTRUCTURES OF HIGH STRENGTH STEEL ON SUSCEPTIBILITY OF CADMIUM EMBRITTLEMENT

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Acta Metallurgica Sinica(English Letters) 1989年第5期2卷 343-347页

作者： TANG Zhizhong LIU Minzhi Chengdu university of science and technology,Chengdu,{3.XIAO Yaotian Institute of Metal Research,Academia Sinica,Shenyang,{3. Dept.of Metal Materials,Chengdu university of science and technology,Chengdu,{3.

The effect of different microstructures of steel 3.CrMnSiNi2A on the susceptibility of cadmium embrittlement has been studied and compared under the unique yield strength level. The results show that the tempered martensite exhibits the maximum susceptibility to cadmium embrittlement,while the lower bainite shows the minimum *** mixed microstructure of the above two has a susceptibility in between.

关键词： steel 3.CrMnSiNi2A microstructure susceptibility of cadmium embrittlement