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A template of rat brain based on fMRI T2. imaging

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Progress in Natural science:Materials International 2005年第6期15卷 502-506页

作者： HU Zhenghui1, WU Yigen2. WANG Xiaochuan3, WANG Jianzhi3, CHEN Feiyan1 and TANG Xiaowei1*(1. Department of Physics and Bio-X Laboratory, Zhejiang university, Hangzhou 31002., China 2. institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques, Chinese Academy of {2.s,Beijing 100039, China 3. Department of Pathophysiology, Tongji Medical College, huazhong university of science and technology, wuhan 430030, China) Department of Physics and Bio-X Laboratory Zhejiang University Hangzhou 310027 China institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques Chinese Academy of Sciences Beijing 100039 China Department of Pathophysiology Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

The development of functional magnetic resonance imaging (fMRI) technology has made it possible to carry out functional brain imaging experiments in small animals. Usually, group data is required to form the assessment of population, which can not only increase the sensitivity of the overall experiment, but also allow the generalization of the conclusion to the whole population. In order to average the signals of functional brain images from different subjects, it is necessary to put all the mapping images into the same standard space (template image). However, up to now, most animal brain templates remain unavailable and it must be done by ourselves. In this study, a template image based on the brains of eight male Wistar rats is obtained, and it is successfully used in our present Alzheimer disease (AD)-like rat model studies as template for spatially normalizing images to the same stereotaxical space. The fMRI results processed with statistical parametric mapping (SPM99) software are in agreement with the results from immunohistochemical experiment, which proves that this method is universally applicable to the pathologic models of other small animals and to human brain lesion studies.

关键词： fMRI animal model atlas template normalization T*2.

Multi-materials drop-on-demand inkjet technology based on pneumatic diaphragm actuator

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science China(Technological sciences) 2010年第6期53卷 1605-1611页

作者： XIE Dan1,2.ZHANG HongHai1,2.SHU XiaYun1,2.Xiao JunFeng1,2.& CAO Shu1,2.1institute of Micro-Systems,School of Mechanical science and Engineering,{2.,wuhan 43.074,China 2.4} National Laboratory for Optoelectronics,wuhan 43.074,China 1. institute of Micro-Systems School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China2. Wuhan National Laboratory for Optoelectronics Wuhan 430074 China

Micro-droplet jetting belongs to the field of precision fluid dispensing *** traditional subtraction manufacture process,micro-droplet jetting as an additive fabrication technique with features of non-contact and data-driven represents a new development trend of modern manufacturing *** this paper,the design,fabrication and performance of a multi-materials drop-on-demand (DOD) inkjet system based on pneumatic diaphragm actuator were *** capturing the droplet ejection process and measuring the droplet dimension,a self-made in situ imaging system based on time delayed external trigger was set *** performance of the generator was studied by adjusting the structure and control ***,the influence of fluid properties on the droplet ejection process was experimentally ***-solderballs of 160.5 μm in diameter and UV curing adhesive micro-bumps of 346.94 μm in contact diameter with the substrate were *** results demonstrated that the DOD inkjet generator possesses characteristics of robust,easy to operate and maintain,and able to withstand high temperature as well as applicability to a wide variety of materials including polymers,low melting point resin and high melting point *** system has a great potential of being used in the fields of IC and MEMS packaging,3D printing,organic semiconductor fabrication,and biological and chemical analysis.

关键词： micro-droplet jetting drop on demand pneumatic diaphragm actuator multi-materials

Multispectral image fusion method based on intensity-hue-saturation and nonsubsampled three-channels non-separable wavelets

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Chinese Optics Letters 2010年第4期8卷 384-387页

作者：刘斌刘维杰彭嘉雄 School of Mathematics and Computer science Hubei university Computer School Wuhan University institute of Image Recognition and Artificial Intelligence Huazhong University of Science and Technology

A new multispectral image fusion method based on intensity-hue-saturation（IHS） transform and threechannel non-separable wavelets whose dilation matrix is[2.1;1,1]is *** multi-resolution decompositions of the intensity of multispectral image and panchromatic image are performed in nonsubsampled mode using the three-channel non-separable wavelet filter *** approximation images and the detail images of the multi-resolution pyramids are *** experimental results show that this method has good visual *** performance outperforms the IHS fusion *** discrete wavelet transform （DWT） fusion method,and the IHS-DWT fusion method in preserving spectral quality and high spatial resolution information.

关键词： Decomposition Discrete wavelet transforms Filter banks Visual communication

Magnetic Properties of NiCuZn Ferrite Thin Films Prepared by the Sol-gel Method

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Journal of wuhan university of {2.(Materials science) 2007年第3期22卷 506-509页

作者：刘锋 institute of Microelectronics Tsinghua University

Ni0.4Cu0.2.n0.4Fe2.4 thin films were fabricated on Si substrates by using the sol-gel method and rapid thermal annealing （RTA）, and their magnetic properties and crystalline structures were investigated. The samples calcined at and above 600 ℃ have a single-phase spinel structure and the average grain size of the sample calcined at 600 ℃ is about 2. nm. The initial permeability μi, saturation magnetization M and coercivity H of the samples increase with the increasing calcination temperature. The sample calcined at 600 ℃ exhibits an excellent soft magnetic performance, which has μi=33.97 （10 MHz）, Hc=15.62.Oe and Ms=2.8.877 emu/cm^3. Low-temperature annealing can enhance the magnetic properties of the samples. The work shows that using the sol-gel method in conjunction with RTA is a promising way to fabricate integrated thin-film devices.

关键词： Ni0.4Cu0.2.n0.4Fe2.4 thin films, sol-gel-method rapid thermal processing magnetic properties

Shape Character of Fusion-solidification Zone of EBW Joints for Titanium Alloy

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稀有金属材料与工程 2011年第S4期40卷 74-78页

作者： Fu Pengfei1,2.Mao Zhiyong2.Wang Yajun3,Gong Shuili2.Liu Xin2.1School of Materials science and Engineering,huazhong university of science and technology,{2.,China 2.0} and technology on Power Beam Processes Laboratory,Beijing Aeronautical Manufacturing technology Research institute,Beijing 10002.,China3School of Mechanical Engineering and Automation,Beijing university of Aeronautics and Astronautics,Beijing 100191,China Beijing Aeronaut Mfg Technol Res Inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China huazhong Univ Sci & Technol Sch Mat Sci & Engn Wuhan 430074 Peoples R China Beijing Univ Aeronaut & Astronaut Sch Mech Engn & Automat Beijing 100191 Peoples R China

Shape character of fusion-solidification zone of electron beam welding (EBW) joints was studied for TC4 *** typical shapes of the fusion-solidification zone were gained by appropriate welding *** shapes and dimensions of the fusion-solidification zone of TC4 titanium joints were apparently influenced by processing parameters,focusing state and power density *** on the analyses of processing parameters,focusing state and power density distribution,the integrated parameters of n1 and n2.were put forward,which represented the distribution and intensity of electron beam *** a series of the formulations are developed to predict the shape of fusion-solidification zone by the processing parameters.

关键词： electron beam welding (EBW) titanium alloy fusion-solidification zone mathematical model

No apparent lock-in depth of the Laschamp geomagnetic excursion: Evidence from the Malan loess

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science China Earth sciences 2006年第9期49卷 960-967页

作者： ZHU Rixiang1, LIU Qingsong1,2. PAN Yongxin1, DENG Chenglong1, ZHANG Rui1 & WANG Xianfeng3 1. Paleomagnetism and Geochronology Laboratory (SKL of Lithosphere Evolution), institute of Geology and geophysics, Chi- nese Academy of {2.s, Beijing 10002., China 2. institute of geophysics and Planetary geophysics, university of California, Santa Cruz, CA 95064, USA 3. Department of Geology and geophysics, university of Minnesota, Minneapolis, MN 55455, USA 1. Paleomagnetism and Geochronology Laboratory (SKL of Lithosphere Evolution) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 2. institute of geophysics and Planetary geophysics University of California Santa Cruz CA 95064 USA 3. Department of Geology and geophysics University of Minnesota Minneapolis MN 55455 USA

The first-order chronological framework of the long-term Chinese loess/paleosol sequences was based mainly on magnetostratigraphy. However, there remain arguments on the lock-in ages of the major geomagnetic reversals. This study systematically compared the stratigraphic locations of the Laschamp excursion and Henrich events (H4 at～39 ka and H5 at～48 ka) recorded by the Luochuan loess profile in the central Chinese Loess Plateau. Results show that the Lascchamp excursion is bracketed well by these two cold events, and the corresponding estimated age is between about 41.7-43.7 ka, which is close to the widely accepted age of ～40-41 ka for the ***, our new results do not suggest apparent lock-in effects in the last glacial Malan loess.

关键词： Chinese loess, Laschamp excursion, Henrich event, lock-in depth.

Energy Efficient Beacon Discovering Scheme for Node Localization in Wireless Sensor Networks

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wuhan university Journal of Natural {2.s 2010年第4期15卷 303-307页

作者： LIU Xinxin1,2. ZHAO Erdun3, CHEN Kun2.1. School of Computer, wuhan university, wuhan 430072. Hubei, China 2. wuhan Digital Engineering Research institute, wuhan 43.074, Hubei, China 3. Department of Computer science, huazhong Normal university, wuhan 430079, Hubei, China School of Computer Wuhan University Wuhan Hubei China wuhan Digital Engineering Research institute Wuhan Hubei China Department of Computer science Huazhong Normal University Wuhan Hubei China

Efficient sensor node localization is a crucial part of many location-dependent applications that utilize wireless sensor networks (WSNs). To cope with the problem of insufficient bea-con node for localization,we design a beacon discovery protocol in this paper that helps the blind node to find beacons nearby and present an energy efficient scheme for the beacon that receives the request from a blind node to adjust its radio range. We obtain the relationship between the mean energy consumption with adjust-ment number by the mathematical analysis. Numerical results show that great energy saving is achieved when the optimal ad-justment number is adopted.

关键词： localization wireless sensor networks energy- efficient radio range adjustment

Effect and mechanism of stresses on rock permeability at different scales

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science China Earth sciences 2006年第7期49卷 714-723页

作者： YIN Shangxian1 & WANG Shangxu2.1. Safety Engineering College, North China institute of science and {2., Yanjiao, Beijing 101601, China 2. Key Laboratory of geophysics Exploration, China university of Petroleum, Beijing 100083, China 1. Safety Engineering College North China Institute of Science and Technology Yanjiao Beijing 101601 China 2. Key Laboratory of geophysics Exploration China University of Petroleum Beijing 100083 China

The effect of geo-stress fields on macroscopic hydro-geological conditions or micro-cosmic permeability of water-bearing media should follow some laws or principles. Cases study and tests show that: (1) At macro-geologic large scale, deformed and crashed rocks which were induced by geo-stress fields changing provided space for groundwater storage and flow. Groundwater adjusts water-bearing space and dilatants fractures by flowing and press transferring. Coupling of liquid and solid can be implemented for rocks and groundwater. Although tectonic fields witness several times of change and build-up in geological time, stress fields forming regional tectonic framework are coherent with seepage fields, orientation of the maximum horizontal stress demonstrates main seepage direc-tions. (2. At macro-geologic middle scale, zones of stresses changing sharply, quite low stresses, stress or shear concentration can be used to show locations and types of main fractures, zones of geo-stresses changing equably can be acted as normal base media zones of tri-porosity media. (3) At micro-geologic small scale, tri-porosity media include fractured rocks, porous rocks and capillary rocks. Investigations indicate that porosity or permeability is functions of effective stresses, and po-rosity or permeability changing rules of porous rocks with variation of effective stresses can be de-scribed as the index model, the model of power exponent functions is suitable for those of fractured rocks, the model of the second power parabola for capillary rocks. The porosity and permeability loss in fractured rocks, which are greater than that in porous rocks, are shown by calculation of effective compressive coefficient and closing pressure in cracks. The calculations can also explain the mecha-nism why porosity changes are always larger than permeability changes. It is proved by the thick wall cylinder theory that the second power parabola relation between porosity or permeability loss and effective

关键词： geo-stress fields, seepage fields, tri-porosity media, effective stresses, permeability, porosity,scale.

A new approach based on PSO algorithm to find good computational encoding sequences

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Progress in Natural science:Materials International 2007年第6期17卷 712-716页

作者： Cui Guangzhao1, Niu Yunyun1, Wang Yanfeng1, Zhang Xuncai2.and Pan Linqiang2.1. School of Electrical and Electronic Engineering, Zhengzhou university of Light Industry, Zhengzhou 450002. China 2. Research institute of Biomolecular Computer, {2., wuhan 43.074, China) [a]School of Electrical and Electronic Engineering Zhengzhou University of Light Industry Zhengzhou China [b]Research institute of Biomolecular Computer Huazhong University of Scienc and Technology Wuhan China

Computational encoding DNA sequence design is one of the most important steps in molecular computation. A lot of research work has been done to design reliable sequence library. A revised method based on the support system developed by Tanaka et al. is proposed here with different criteria to construct fitness function. Then we adapt particle swarm optimization (PSO) algorithm to our encoding problem. By using the new algorithm, a set of sequences with good quality is generated. The result also shows that our PSO-based approach could rapidly converge at the minimum level for an output of the simulation model. The celerity of the algorithm fits our requirements.

关键词： DNA computing computational encoding DNA sequences PSO algorithm fitness function