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A Novel Fast Algorithm of Mono transition region Determination with Gray Image

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Wuhan University Journal of Natural Sciences 2004年第3期9卷 309-312页

作者： ZhangAi-hua CollegeofComputerScienceandTechnology HuazhongUniversityofScienceandTechnologyWuhan430074HubeiChina

There is a transition region between objects and background in any gray image. Many valuable applications of image segmentation and edge detection based on transition region determination have been developed in recent years. But, the complexity of calculation for determining transition region is too high. It results in the very limitation of applications based on transition region. A new novel fast method for transition region determination is presented in this paper, which will reduce the complexity of calculation dramatically. Many experiments have showed that this algorithm is effective and correct and will lay a good foundation for applications based on transition region. Key words image segmentation - transition region - maximum point - efficient average gradient (EAG) CLC number TP 391.4 Biography: Zhang Ai-hua (1965-), male, Ph. D candidate, research direction: image processing.

关键词： image segmentation transition region maximum point efficient average gradient (EAG)

OBSERVATIONAL STUDY OF MICROPHYSICS IN THE STRATIFORM region AND transition region OF A MIDLATITUDE MESOSCALE CONVECTIVE COMPLEX

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Acta meteorologica Sinica 1991年第5期5卷 527-540页

作者：叶家东范蓓芬 WilliamR.Cotton MichaelA.Fortune Department of Atmospheric Sciences Nanjing UniversityNanjing Department of Atmospheric Sciences Colorado State UniversityU.S.A.

Cloud microphysical data observed with PMS probes have been combined with radar and other in-situ data collected by a NOAA P-3 aircraft that flew through the stratiform and transition regions of a mesoscale convective complex(MCC).The combined data have been analyzed with respect to the mescscale structure of the storm *** characteristics of ice particles in the transition and stratiform regions were quite *** ice particle concentrations in the transition region were about 4 to 6 times that found in the stratiform region,and the size of ice particles in the stratiform region was about twice that in the transition *** relatively lower radar reflectivity in the transition region is a result of smaller particle *** main precipitation particle growth mechanisms are riming and aggregation in the transition region ard the aggregation process predominates in the stratiform region referred from the microphysical *** ag- gregation starts in the upper,colder levls but becomes more efficient as the particles approach the melting layer.

关键词： mesoscale convective complex transition region stratiform region microphysical structure aggregation process

Influence of the deposition parameters on the transition region of hydrogenated silicon films growth

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Chinese Physics B 2005年第11期14卷 2342-2347页

作者：雷青松吴志猛耿新华赵颖奚建平 Institute of Micro and Nano Science and Technology Shanghai Jiaotong University Shanghai 200030 China Institute of Photo-Electronics Nankai University Tianjin 300071 China

Hydrogenated microcrystalline and amorphous silicon thin films were prepared by very high frequency plasmaenhanced chemical vapour deposition （VHF PECVD） by using a mixture of silane and hydrogen as source gas. The influence of deposition parameters on the transition region of hydrogenated silicon films growth was investigated by varying the silane concentration （SC）, plasma power （Pw）, working pressure （P）, and substrate temperature （Ts）. Results suggest that SC and Ts are the most critical factors that affect the film structure transition from microcrystalline to amorphous phase. A narrow region in the range of SC and Ts, in which the rapid phase transition takes place, was identified. It was found that at lower P or higher Pw, the transition region is shifted to larger SC. In addition, the dark conductivity and photoconductivity decrease with SC and show sharp changes in the transition region. It proposed that the transition process and the transition region are determined by the competition between the etching effect of atomic hydrogen and the growth of amorphous phase.

关键词： microcrystalline silicon amorphous silicon transition region VHF PECVD

A NEW ALGORITHM FOR DETECTING THE transition region ON NOISE IMAGE

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维普期刊数据库

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Journal of Electronics(China) 2003年第4期20卷 279-284页

作者： Wang Hui Luo Jianping(Faculty of Information Eng., Shenzhen University, Shenzhen 518060) Faculty of Information Eng. Shenzhen University Shenzhen

An algorithm of ramp width reduction based on the gray information of neighborhood pixels is proposed, which can sharpen the ramp edge effectively. Then, a new gray-weighted gradient operator and the automatic method to determine its parameter are introduced when detecting the transition region of images. Gray-weighted gradient operator can not only make the correlation of gradient and gray information as big as possible, but also resist the noise in the images. Some experiments show that the algorithm in this paper can extract the transition region more effectively.

关键词： Ramp edge Width reduction transition region Gray-weighted gradient operator

Continuous chemical redistribution following amorphous-to-crystalline structural ordering in a Zr-Cu-Al bulk metallic glass

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Journal of Materials Science & Technology 2022年第6期101卷 285-293页

作者： Xuelian Wu Si Lan Xiyang Li Ming Yang Zhenduo Wu Xiaoya Wei Haiyan He Muhammad Naeem Jie Zhou Zhaoping Lu Elliot Paul Gilbert Dong Ma Xun-Li Wang Department of Physics City University of Hong KongHong KongChina Herbert Gleiter Institute of Nanoscience School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Quantum Matter Institute University of British ColumbiaVancouverBritish Columbia V6T 1Z4Canada Neutron Sciences Platform Songshan Lake Materials LaboratoryDongguan 523808China Center for Neutron Scattering and Applied Physics City University of Hong Kong Dongguan Research InstituteDongguan 523000China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Australian Centre for Neutron Scattering Australian Nuclear Science and Technology OrganisationLucas HeightsNew South Wales 2234Australia City University of Hong Kong Shenzhen Research Institute Shenzhen 518057China

Bulk metallic glasses(BMGs)are thermodynamically *** such,crystallization occurs when a BMG is thermally annealed at a temperature above the glass transition *** extensive studies have been performed on the crystallization kinetics of BMGs,most of them have focused on the amorphous-to-crystalline structural ordering,and little attention has been paid to chemical distribution and its relationship with the structural ordering during the crystallization *** this paper,a new approach,with simultaneous differential scanning calorimetry(DSC)and small angle neutron scatter-ing(SANS)measurements,was applied to study in situ the crystallization of a Zr_(45.5)Cu_(45.5)Al_(9)BMG upon isothermal annealing at a temperature in the supercooled liquid *** analysis of the DSC and SANS data showed that the structural evolution during isothermal annealing could be classified into three stages:(Ⅰ)incubation;(Ⅱ)amorphous-to-crystalline structural ordering;(Ⅲ)continuous chemical *** finding was validated by composition analysis with atom probe tomography(APT),which further identified a transition region formed by expelling Al into the *** transition re-gion,with a composition of(Cu,Al)_(50)Zr_(50),served as an intermediate step facilitating the formation of a thermodynamically stable crystalline phase with a composition of(Cu,Al)_(10)Zr_(7).

关键词： Bulk metallic glass Crystallization In situ Continuous chemical redistribution transition region

An Impulsive Heating Model for the Evolution of Coronal Loops

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Chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 608-616页

作者： Li Feng Wei-Qun Gan Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 Max Planck Institute for Solar System Research Max-Planck-Str. 2 37191 Katlenburg-LindauGermany

It was suggested by Parker that the solar corona is heated by many small energy release events generally called microflares or nanoflares. More and more observations showed flows and intensity variations in nonflaring loops. Both theories and observations have indicated that the heating of coronal loops should actually be unsteady. Using SOLFTM （Solar Flux Tube Model）, we investigate the hydrodynamics of coronal loops undergoing different manners of impulsive heating with the same total energy deposition. The half length of the loops is 110 Mm, a typical length of active region loops. We divide the loops into two categories： loops that experience catastrophic cooling and loops that do not. It is found that when the nanoflare heating sources are in the coronal part, the loops are in non-catastrophic-cooling state and their evolutions are similar. When the heating is localized below the transition region, the loops evolve in quite different ways. It is shown that with increasing number of heating pulses and inter-pulse time, the catastrophic cooling is weakened, delayed, or even disappears altogether.

关键词： hydrodynamics -- Sun corona -- Sun transition region

Interface behavior and microstructure transformation of welded joint of 35CrMo steel by electro-spark deposition

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China Welding 2005年第1期14卷 15-18页

作者：张富巨马立卿张国栋孙峰 Welding Institute Wuhan University Wuhan 430072

Electro-spark deposition has been carried out on the 35CrMo steel by filling and restoring the simulated slot specimens, and continuous surface coating with extra low porosity was obtained with proper parameters. The microstructure transformation and interface behavior of deposited joint were observed and analyzed. It shows that a transition region with 15μm in depth was obtained between base metal and deposited metal, and metallurgical bonding was achieved between restored base metal and deposition coating.

关键词： electro-spark deposition transition region metallurgical bonding

Modified Gray Level Difference-Based Thresholding Segmentation and its Application in X-Ray Welding Image

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Journal of Shanghai Jiaotong university(Science) 2013年第4期18卷 448-453页

作者：佟彤蔡艳孙大为吴毅雄 Shanghai Key Laboratory of Materials Laser Processing and Modification Shanghai Jiaotong University

Thresholding is a popular image segmentation method that often requires as a preliminary and indis- pensable stage in the computer aided image process, particularly in the analysis of X-ray welding images. In this paper, a modified gray level difference-based transition region extraction and thresholding algorithm is presented for segmentation of the images that have been corrupted by intensity inhomogeneities or noise. Classical gray level difference algorithm is improved by selective output of the result of the maximum or the minimum of the gray level with the pixels in the surrounding, and multi-structuring of neighborhood window is used to represent the essence of transition region. The proposed algorithm could robustly measure the gray level changes, and accurately extract transition region of an image. Comparisons with other approaches demonstrate the superior performance of the proposed algorithm. K

关键词： image segmentation transition region gray level difference welding image

Research on the optimum hydrogenated silicon thin films for application in solar cells

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Chinese Physics B 2006年第12期15卷 3033-3038页

作者：雷青松吴志猛耿新华赵颖孙健奚建平 Institute of Micro and Nano Science and Technology Shanghai Jiaotong University Shanghai 200030 China Institute of Photo-electronics Nankai University Tianjin 300071 China

Hydrogenated silicon （Si：H） thin films for application in solar ceils were deposited by using very high frequency plasma enhanced chemical vapour deposition （VHF PECVD） at a substrate temperature of about 170 ℃, The electrical, structural, and optical properties of the films were investigated. The deposited films were then applied as i-layers for p-i-n single junction solar cells. The current-voltage （I - V） characteristics of the cells were measured before and after the light soaking. The results suggest that the films deposited near the transition region have an optimum properties for application in solar cells. The cell with an i-layer prepared near the transition region shows the best stable performance.

关键词： hydrogenated silicon thin film transition region Si:H thin film solar cell stability