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Interaction between electromagnetic waves and energetic particles by a realistic density model

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science China(Technological sciences) 2010年第9期53卷 2552-2557页

作者： HE YiHua1,2.CHEN LiangXu1,XIAO FuLiang1 & YANG Chang1 1 School of Physics and Electronic sciences,Changsha university of science and {3.,Changsha 410004,China 2.State Key Laboratory of Space Weather,Chinese Academy of sciences,Beijing 100190,China 1. School of Physics and Electronic sciences Changsha University of Science and Technology Changsha 410004 China2. State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China

Using a realistic density model,we present a first study on the interactions between electromagnetic waves and energetic particles in the inner *** calculations show that as the latitude λ increases,the number density ne increases,and resonant frequency range moves to lower pitch *** L-mode/electron and L-mode/proton interactions,the pitch angle diffusion dominates over the momentum *** indicates that L-mode waves are primarily responsible for pitch angle *** R-mode/electron interaction,the momentum diffusion is found to be comparable to the pitch angle diffusion,implying that R-mode waves can play an important role in both pitch angle scattering and stochastic acceleration of *** R-mode/proton interaction,diffusion coefficients locate primarily below pitch angle 60° and increase as kinetic energy increases,suggesting that R-mode waves have potential for pitch angle scattering of highly energetic (~1 MeV) protons but cannot efficiently accelerate protons.

关键词： wave-particle interaction energetic particles resonant frequency pitch angle and momentum diffusion density model

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任意网格模型的相似度评估

系统仿真学报 2005年第1期17卷 16-19,24页

作者：唐杰张福炎南京大学计算机科学与技术系南京210093

提出了一种任意网格模型相似度评估机制及其实现方法。该算法以对称Hausdorff距离为基础,综合考虑了网格模型的几何相似性和外观相似性。在相似度计算过程中,采用平均单元格数据结构管理网格模型中的三角片,并根据三角片的大小自适应选... 详细信息

提出了一种任意网格模型相似度评估机制及其实现方法。该算法以对称Hausdorff距离为基础,综合考虑了网格模型的几何相似性和外观相似性。在相似度计算过程中,采用平均单元格数据结构管理网格模型中的三角片,并根据三角片的大小自适应选择单元格的大小,保证了算法具有较快的运行速度。

关键词：三角网格多分辨模型几何造型网格简化

Fabrication,structure and compression performance of Inconel 617 superalloy honeycomb

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Rare Metals 2007年第S1期26卷 199-204页

作者： WANG Hongwei,WEI Zunjie,ZHU Zhaojun,and LI Zhiwei School of Materials science and Engineering,Harbin institute of {2.,Harbin 150001,China Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

Inconel 617 metal honeycombs with designed porosity,cell size and cell morphology were fabricated using fused deposition modelling rapid prototype *** microstructure and compression properties of Inconel 617 metal honeycomb were *** results indicate that Inconel 617 metal honeycomb structure can be fabricated using fused deposition modelling technique,the processes are simple and the size of honeycomb is *** sintered Inconel 617 honeycombs consist of matrix,γ phase,and grain boundary precipitates,Cr7C3.and M2.0}6 type *** honeycomb microstructure sintered using fine powder particles are denser than that of coarse powder *** strength and Young’s modulus increase with the relative density of honeycomb *** the influence of the relative density on Young’s modulus is greater than that of yield strength.

关键词： rapid prototype fused deposition modelling metal honeycomb compression properties

Resonance scattering spectral detection of ultratrace IgG using immunonanogold-HAuCl_4-NH_2.H catalytic reaction

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science China Chemistry 2008年第5期51卷 440-446页

作者： JIANG ZhiLiang1,2.ZHANG ShengSen1,LIANG AiHui2.& HUANG SiYu1 1 School of Environment and Resource,Guangxi Normal university,Guilin 541001,China 2.Department of Material and Chemical Engineering,Guilin university of {2.,Guilin 541001,China 1. School of Environment and Resource Guangxi Normal University Guilin 541001 China 2. Department of Material and Chemical Engineering Guilin University of Technology Guilin 541001 China

Nanogold particles of 10 nm were used to label goat anti-human IgG (GIgG) to obtain nanogold-labeled GIgG (AuGIgG). In a citrate-HCl buffer solution of pH 2.2.,AuGIgG showed a strong catalytic effect on the reaction between HAuCl4 and NH2.H to form big gold particles that exhibited a resonance scatter-ing (RS) peak at 796 nm. Under the chosen conditions,AuGIgG combined with IgG to form immuno-complex AuGIgG-IgG that can be removed by centrifuging at 16000 r/min. AuGIgG in the centrifuging solution also showed catalytic effect on the reaction. On those grounds,an immunonanogold catalytic RS assay for IgG was designed. With addition of IgG,the amount of AuGIgG in the centrifuging solution decreased; the RS intensity at 796 nm (I796 nm) decreased linearly. The decreased intensity ΔI796 nm was linear with respect to the IgG concentration in the range of 0.08-16.0 ng·mL-1 with a detection limit of 0.02.ng·mL-1. This assay was applied to analysis of IgG in sera with satisfactory sensitivity,selectivity and rapidity.

关键词： immunonanogold nanocatalysis gold-enhancement resonance scattering assay IgG

Cyclostationary Property Based Spectrum Sensing Algorithms for Primary Detection in Cognitive Radio Systems

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Journal of Shanghai Jiaotong university(science) 2009年第6期14卷 676-680页

作者：岳文静郑宝玉孟庆民 Department of Electronic Engineering Shanghai Jiaotong University institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications

To implement the primary signal without interference in cognitive radio systems, cognitive radios can detect the presence of the primary user in low SNR. Currently, energy detector is the most common way of spectrum sensing because of its low computational complexity. However, performunce of the method will be possibly degraded due to the uncertainty noise. This paper illustrates the benefits of one-order and two-order cyclostationary properties of primary user＇s signals in time domain. These feature detection techniques in time domain possess the advantages of simple structure and low computational complexity comparing with spectral feature detection methods. Furthermore, performance of the one-order and two-order feature detection is studied and the analytical results are given. Our analysis and numerical results show that the sensing performance of the one-order feature detection is improved significantly comparing with conventional energy detector since it is robust to noise. Meanwhile, numerical results show that the two-order feature detection technique is better than the one-order feature detection. However, this benefit comes at the cost of hardware burdens and power consumption due to the additional multiplying algorithm.

关键词： cognitive radio spectrum sensing cyclostationary feature detection

Waiting time in block fading MIMO systems with dynamic-depth interleaving

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science China(Information sciences) 2010年第8期53卷 1622-1627页

作者： GUO HaiYou 1,2., HU HongLin 1,2.& ZHANG Yan 3.1 Key Laboratory of Wireless Sensor Network & Communication, Shanghai institute of Microsystem and Information {2., Chinese Academy of {2.s, Shanghai 2.0050, China 2.Shanghai Research Center for Wireless Communications, Shanghai 2.03.5, China 3.Simula Research Laboratory, Lysaka 13.5, Norway 1. Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China2. Shanghai Research Center for Wireless Communications Shanghai 200335 China3. Simula Research Laboratory Lysaka 1325 Norway

Interleaving is an efficient measure to resolve the bursty errors in a block fading multiple-inputs multiple-outputs (MIMO) system. For the metrics of network layer, interleaving exerts two conflicting effects on the ultimate delay performance. Specifically, interleaving can advantageously reduce data transmit time. On the other hand, it comes at a cost, entailing an undesired delay penalty resulting from interleaving depth. Here, we exploit a unified model to accommodate these two conflicting effects, and derive the average waiting time in block fading MIMO systems with dynamic-depth interleaving. Such a unified model is developed with a combined method of both information theory and queueing theory. Therefore, the model is capable of characterizing the randomness of data arrival process, hence the nature of dynamic-depth interleaving. The methodology and the results are applicable to designing, evaluating, and tuning the practical interleaving systems.

关键词： dynamic-depth interleaving multiple-inputs multiple-outputs (MIMO) queueing analysis waiting time

APPLICATIONS OF INTEGRATED SEMIGROUPS TO HIGHER ORDER ABSTRACT CAUCHY PROBLEMS

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Systems science and Mathematical sciences 1992年第4期5卷 316-327页

作者： ZHENG Quan (Department of Mathematics,Huazhong university of science and {2.,Wuhan 43.074,China)

This paper is concerned with applications of integrated semigroups tothe following Cauchy problem:（ACPn） xn（t）=sum from i=0 to n-1 Bixi（t）,xi（0）=xi,0（?）i（?）n-1where Bi （0（?）i（?）n-1） are closed linear operators on a Banach space *** theorem,a condition of the solvability,a condition of the exponentialwell-posedness,and some results for the special case that Bn-1 is bounded andD(Bn-2./sub>)（?）D（Bi）（0（?）i（?）n-3. are obtained.

关键词： Higher order abstract Cauchy problem uniqueness solvability exponential well-posedness integrated semigroup

AN ACCURATE SOLUTION OF CHARACTERISTIC IMPEDANCE OF THE ELLIPTIC STRIP-LINE

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Journal of Electronics(China) 1985年第3期2卷 222-232页

作者：潘宗达 nanjing Research institute of Electronic {2.

An accurate solution of characteristic impedance of the elliptic strip-line with conformal trans-formation is developed. Some data are given, which are useful for designing elliptic strip--lines.

关键词： line

Parallel Algorithm in Surface Wave Waveform Inversion

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Wuhan university Journal of Natural sciences 2001年第Z1期6卷 574-578页

作者： Cao Xiao lin, Song Jun qiang School of Computer science, National university of Defense {2., Changsha 410073. China School of Computer science National University of Defense Technology Changsha China

In Surface wave waveform inversion, we want to reconstruct 3. shear wave velocity structure, which calculation beyond the capability of the powerful present day personal computer or even workstation. So we designed a high paralleled algorithm and carried out the inversion on Parallel computer based on the partitioned waveform inversion (PWI). It partitions the large scale optimization problem into a number of independent small scale problems and reduces the computational effort by several orders of magnitude. We adopted surface waveform inversion with a equal block(2. o×2. o) discretization.

关键词： surface wave waveform inversion parallel algorithm partitioned waveform inversion