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Rapid Fabrication of CdS Nanocrystals with Well Mesoporous Structure Under Ultrasound Irradiation at Room Temperature

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Chemical Research in Chinese Universities 2012年第1期28卷 124-128页

作者： YU Chang-lin1, ZHOU Wan-qin2.3, YU Jim-my4, YANG Jian-gao5 and FAN Qi-zhe1 1. School of Metallurgy and Chemical Engineering, 2. School of information Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, P. R. china 3. Fujian Provincial Key {2. of Photocatalysis-State Key {2. Breeding Base, Fuzhou University, Fuzhou 350002. P. R. china 4. Department of Chemistry, Center of Novel Functional Molecules, and Environmental Science Programme, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, P. R. china 5. Engineering Research Center of High-efficiency Development and application Technology of Tungsten Resources, ministry of education, Jiangxi University of Science and Technology, Ganzhou 341000, P. R. china Jiangxi Univ Sci & Technol Sch Met & Chem Engn Ganzhou 341000 Peoples R China Jiangxi Univ Sci & Technol Sch Informat Engn Ganzhou 341000 Peoples R China Fuzhou Univ Fujian Prov Key Lab Photocatalysis State Key Lab Breeding Base Fuzhou 350002 Peoples R China Chinese Univ Hong Kong Dept Chem Ctr Novel Funct Mol Shatin Hong Kong Peoples R China Chinese Univ Hong Kong Environm Sci Programme Shatin Hong Kong Peoples R China Jiangxi Univ Sci & Technol Minist Educ Engn Res Ctr High Efficiency Dev & Applicat Techn Ganzhou 341000 Peoples R China

Sphere-like mesoporous CdS nanocrystals with high crystallinity and big surface area were successfully fabricated by ultrasound irradiation at room temperature. The as-synthesized CdS with and without ultrasound irra diation was investigated by the characterizations of X-ray diffraction（XRD）, scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, and Brunauer-Emmett-Teller（BET） surface areas. The photocatalytic acti vity of the CdS was evaluated by photocatalytic degradation of methyl orange under visible light（λ〉42. nm） irradia tion. A possible mechanism for the formation of the CdS nanocrystals with mesoporous structure under ultrasound irradiation was proposed. The results show that both the template role of the triblock copolymer of P12. and the effect of ultrasound-induced aggregation are mainly responsible for the formation of mesoporous structure. On the other hand, the energy generated from acoustic cavitation can effectively accelerate the crystallization process of the amorphous CdS.

关键词： CdS Crystallinity Mesoporous structure Ultrasound-induced aggregation

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基于激光扫描数据的室外场景表面重建方法

系统仿真学报 2005年第2期17卷 384-387,391页

作者：张爱武孙卫东李风亭首都师范大学三维空间信息获取与地学应用教育部重点实验室北京100037 清华大学电子工程系北京100084

针对激光扫描特点,提出了一种自适应室外场景表面重建方法。首先,定义无效数据与有效数据,提取主要被测物;接着,通过边缘提取、拐点确定和表面曲率估计进行自适应重采样;然后,识别空洞,区分物体,给出网格剖分方法。实验验证了算法既可... 详细信息

针对激光扫描特点,提出了一种自适应室外场景表面重建方法。首先,定义无效数据与有效数据,提取主要被测物;接着,通过边缘提取、拐点确定和表面曲率估计进行自适应重采样;然后,识别空洞,区分物体,给出网格剖分方法。实验验证了算法既可去除冗余数据又可突出重要边缘信息,有利于激光扫描数据的存储和传输。

关键词：自适应采样特征提取 Hough变换曲率三维重建

An improved approach to the efficient construction of and search operations in motion graphs

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Science china(information Sciences) 2012年第5期55卷 1042-1051页

作者： GAO Yan 1,CHEN ZhiHua 2.CHEN MinGang 3 & SHEN Yang 3 1 Software Engineering Institute,East china Normal University,Shanghai 2.0062.china 2.Department of Computer Science and Engineering,East china University of Science and Technology,Shanghai 2.02.7,china 3 Department of Computer Science and Engineering,Shanghai Jiao Tong University,Shanghai 2.02.0,china 1. Software Engineering Institute East China Normal University Shanghai 200062 China2. Department of Computer Science and Engineering East China University of Science and Technology Shanghai 200237 China3. Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Motion graphs have been widely used as an effective technique in the synthesis of human *** synthesize well-formed motions,motion graphs require smooth transitions and good ***,the time and costs grow quadratically as the graph size *** this paper,we present a method to set up a hierarchical structure,called a structure *** coarse level of this graph models different motion categories and their transitions,and the fine level mainly captures different motion *** interpolation space method is used to improve the graph connectivity at the fine *** structure guides the establishment of a faster and more realistic graphical *** the building process,this structure also helps with searching the motion graph,by performing a traverse search and placing the findings into a direct look-up table or local search ***,when there is no direct link between the different motions,a navigation map is introduced to conduct an appropriate search path via a series of transition motion *** experimental results indicate that our approach could lower the computation time in construction and searching,while simultaneously providing a richer variety of motion styles.

关键词： motion graph structure table registration curve motion interpolation

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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

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车载激光点云海量数据的管理与快速显示

系统仿真学报 2008年第S1期20卷 33-35,39页

作者：李婕钟若飞赵文吉首都师范大学三维信息获取与应用教育部重点实验室北京100037

就提高车载三维信息采集与获取系统中海量点云数据的管理与显示问题,提出了一种数据访问效率的优化方案。该方案采用磁盘映射方式读取数据并引入分块索引的方法进而在VC++环境下成功编写调度模块,可为三维数据的显示过程点云数据管理软... 详细信息

就提高车载三维信息采集与获取系统中海量点云数据的管理与显示问题,提出了一种数据访问效率的优化方案。该方案采用磁盘映射方式读取数据并引入分块索引的方法进而在VC++环境下成功编写调度模块,可为三维数据的显示过程点云数据管理软件调用。将所有的点云数据分块,通过块号查找,快速提高点云数据的查找速度,为结合OpenGL函数库以实现数据的显示提供基础,其算法思路简单且耗时少。

关键词：车载测量数据采集海量数据激光点云

Discoticnematic Triphenylene Derivertives and their application to an Optically Anisotropic Film

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Discoticnematic Triphenylene Derivertives and their Applicat...

Video retargeting using optimized crop-and-scale

Fifth International Conference on Surface Engineering

作者： Chunxiu Zhang1 2.Jialing Pu1 Zhiqun He2.1 information Recording Materials Lab beijing Institute of Graphic Communication beijing102.00 china 2.Key laboratory of Luminescence and Optical information ministry of education Institute of Optoelectronic Technology beijing Jiaotong University beijing 100044 china

The triphenylne derivatives are chosen as one of negative birefringent materials to form a compensator for widening the viewing *** liquid crystal molecules have positive birefringence in refractive *** anisotropy causes light leakage and results in narrow range of the viewing angle of the *** our study,a series of novel discotic triphenylene derivertives bearing one triphenylene discogen as core and three cyano-biphenyl moities was synthesized and their thermal behaviors were studied using polarizing optical microscope,differential scanning calorimeter and X-ray *** was found that those molecules containing even numbers of methylene spacers showed nematic *** being mixed with MMA（methyl methacrylate）,they also showed nematic phase at the mesophase temperature *** hybrid mode alignment of the molecules can be fixed by photopolymerization of acryloyl *** the alignment of the discotic molecules can be freely controlled,a new area of optically anisotropic film will be produced.

关键词： discotic liquid crystal triphenylene derivertives discoticnematic optically anisotropic film

来源： cnki会议评论

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Journal of Shanghai University(English Edition) 2011年第4期15卷 331-334页

作者：薛银珠杜欢刘志张兆杨 School of Communication and information Engineering Shanghai University Key laboratory of Advanced Display and System application (Shanghai University) Ministry of EducationShanghai 200072P.R.China

Mobile devices are increasingly powerful in multimedia transmitting and browsing. However, the small screen and different aspect ratios of mobile devices lower visual quality while watching images or videos. Video retargeting is aim at fitting an existing video into arbitrary size and aspect ratio. Previous content-aware retargeting methods are mostly high computational cost, which limits their applications on the portable devices with low computation ability. In this paper, a new crop-and-scale approach is presented to adapt video to better suit the target display. We automatically find the optimal parameters of cropping window using the dynamic programming method,, and then scale it to fit the target display. The cropping window can smoothly shift during a shot to follow the movement＇of important objects. The retargeting results using our approach introduce no deformation and jitter effects over the whole video. Experimental results show the success of our approach on adapting a variety of source videos to small display sizes.

关键词： crop-and-scale dynamic programming video retargeting

A novel key pre-distribution scheme for wireless distributed sensor networks

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Science china(information Sciences) 2010年第2期53卷 288-298页

作者： PEI DingYi 1 , DONG JunWu 1 & RONG ChunMing 2.1 College of Mathematics and information Science, Guangzhou University, Guangzhou 510006, china 2.University of Stavanger, N-4036, Stavanger, Norway 1. College of Mathematics and information Science Guangzhou University Guangzhou 510006 China2. University of Stavanger N-4036 Stavanger Norway

A novel key pre-distribution scheme for sensor networks is proposed, which enables sensor nodes to communicate securely with each other using cryptographic techniques. The approach uses the rational normal curves in the projective space with the dimension n over the finite field F q . Both secure connectivity and resilience of the resulting sensor networks are analyzed. By choosing the parameters q and n properly, this key pre-distribution scheme has some advantages over the previous known schemes. In addition, if the number of the rational normal curves in the scheme becomes too large for an application, the size may be reduced by choosing a part of the curves randomly. This reduction has, shown by our experiments, only minimal impact on secure connectivity and resilience of the resulting sensor network.

关键词： sensor network key pre-distribution scheme combinatorial design rational normal curve projective space finite field

Low-power design and application based on CSD optimization for a fixed coefficient multiplier

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Science china(information Sciences) 2011年第11期54卷 2443-2453页

作者： LIU HongXia & YUAN Bo Key laboratory of ministry of {2. for Wide Band-Gap Semiconductor Devices,School of Microelectronics,Xidian University,Xi’an 710071,china 1. Key laboratory of ministry of {2. for Wide Band-Gap Semiconductor Devices School of Microelectronics Xidian University Xi’an 710071 China

This paper presents a low-power design for a fixed coefficient multiplier,based on the canonic signed digit (CSD) *** proposed technology overcomes the defects of the general CSD method by reducing system power and area substantially without additional *** theoretical basis and a design method are explained in detail in this *** design technology was used to optimize a radio-frequency *** test results show that logic utilization is reduced by 2.%,the total number of registers used is reduced by 2..02.,and the total block memory bits utilization is reduced by 2.%.These results show that the proposed low-power design is an effective method.

关键词： canonic signed digit optimization coefficient of multiplication system power system area logic cell number FPGA test results