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Overview on Zero-watermarking Techniques

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Overview on Zero-watermarking Techniques

Grey Problems of a mechanical Transmission System in a Reliability Study

2.12.International Conference on mechanical engineering and Automation(ICMEA2.12.

作者： YaYa Wang1 a Ke Luo2.b Wei Gao3.4 c 1 Department of Information engineering Binzhou Polytechnic Binzhou Shandong {2. 2.Shaoyang University Library Shaoyang University Shaoyang Hunan 42.000 P.R. china 3.Department of Information Yunnan Normal University Kunming Yunnan {2. 4 Department of Mathematics Soochow University Jiangsu Suzhou 2.5006 P.R. china

Digital watermarking, the technology of embedding special information into multimedia data, is a topic that has recently gained increasing attention all over the world. The watermark of digital images, audio, video, and other media product s in general has been proposed for resolving copyright ownership and verifying the integrity of content. The characteristics and applications of watermark techniques are first introduced, and then the basic concepts and evaluation criteria are expatiated. For further understanding, the zero-watermark techniques from the various aspects are classified and some conventional watermark techniques and algorithms are analyzed in detail. At the same time, their security and performance are compared. Finally, the possible research directions of zero-watermark technology are pointed out.

关键词： Zero-watermarking Digital watermark Copyright protection

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International Journal of Plant engineering and Management 2001年第2期6卷 104-109页

作者： LUO You-xin, CAI An-hui, ZHANG Long-ting, GUO Hui-xin Department of mechanical engineering, Changde Normal {2., Changde 415003. P. R.{3. Department of mechanical engineering Changde Normal CollegeChangde 415003 P. R. China

In the light of the Grey characters of reliability on a mechanical transmission system, Grey problems that could assist in the study on mechanical transmission system were analyzed. For example, the factors of time function，the factors of environment and the factors of people have some relationships with the system in this paper. And then, the methods and procedures, which were based upon the theory of Grey system, were elaborated.

关键词： mechanical transmission system reliability Grey system factor

Natural Convection Heat Transfer From a Hot Rectangular and a Square Corrugated Plate to a Cold Flat Plate

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Journal of Thermal Science 2000年第3期9卷 243-248页

作者： M. A. R. Akhanda F. M. Chowdhury (Department of mechanical engineering, Bangladesh University of engineering and Technology (BUET), Dhaka- 1000, Bangladesh) Department of mechanical engineering Bangladesh University of Engineering and Technology (BUET) Bangladesh

Experimental study of natural convection heat transfer across air layers bounded by a lower hot rectangular and a square corrugated plates to an upper cold flat plate has been carried out. The surroundings of this space are adiabatic. The effect of the angle of inclination, the aspect ratio, the temperature potential and the Rayleigh number on average heat transfer coefficients are investigated within a range of 0°≤75°,, 2.3.≤A≤6.3., 10°≤T ≤3.°, and 3.2.xl04≤RaL≤ 2.2.x106. The developed correlation predicts well the experimental data within an error of ±15%.

关键词： natural convection heat transfer corrugation.

Friction and Cutting Properties of Hot-Filament Chemical Vapor Deposition Micro-and Fine-grained Diamond Coated Silicon Nitride Inserts

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Journal of Shanghai Jiaotong university(Science) 2010年第5期15卷 519-525页

作者：杨国栋沈彬孙方宏 School of mechanical engineering Shanghai Jiaotong University

The micro-crystalline diamond (MCD) and fine-grained diamond (FGD) films are deposited on commercial silicon nitride inserts by the hot-filament chemical vapor deposition (HFCVD) method. The friction andcutting properties of as-deposited MCD and FGD films coated silicon nitride (Si3.4) inserts are comparatively investigated in this study. The scanning electron microscopy (SEM) and Raman spectroscopy are adopted to studythe characterization of the deposited diamond films. The friction tests are conducted on a ball-on-plate typereciprocating friction tester in ambient air using Co-cemented tungsten carbide (WC-Co), Si3.4 and ball-bearing steel (BBS) balls as the mating materials of the diamond films. For sliding against WC-Co, Si3.4 and BBS,the FGD film presents lower friction coeffcients than the MCD film. However, after sliding against Si3.4, the FGD film is subject to more severe wear than the MCD film. The cutting performance of as-deposited MCD and FGD coated Si3.4 inserts is examined in dry turning glass fiber reinforced plastics (GFRP) composite materials,comparing with the uncoated Si3.4 insert. The results indicate that the lifetime of Si3.4 inserts can be prolonged by depositing the MCD or FGD film on them and the FGD coated insert shows longer cutting lifetime than the MCD coated one.

关键词： silicon nitride hot-filament chemical vapor deposition(HFCVD) friction and wear glass fiber reinforced plastics(GFRP)

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微重时矩形容器内静液面形状研究

水动力学研究与进展（A辑） 2003年第1期18卷 38-41页

作者：程绪铎南京经济学院食品科学与工程系江苏南京210003 安庆师范学院物理系安徽安庆246011

本文由力学平衡方程导出了微重时矩形容器内静液面方程 ;通过变换 ,导出了求解静液面形状的迭代公式 ;计算得出了数值结果 ;

关键词：微重接触角 Bond数静液面形状

Typhoon Cloud Image Enhancement by Fuzzy Technique

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Typhoon Cloud Image Enhancement by Fuzzy Technique

Equivalent Simplifying of Tower Structure and Its Application in Overall Analysis of Offshore Platform

第2.届中国气象学会年会灾害天气事件的预警、预报及防灾减灾分会场

作者： Changjiang Zhang1,2. Juan LU1 (1. college of Mathematics, Physics and Information engineering, Zhejiang Normal University, Jinhua,{2. 3.1004 2. State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing,{2. 100081)

A new kind of image measure function is proposed by combing fuzzy theory with other some measures. We use it as the overall fitness function of genetic algorithm to adaptively optimize the nonlinear transform parameters in the nonlinear transform function. Thus an optimal gray transformation curve is obtained to enhance the region of interest for a typhoon cloud image. Experimental results show that the proposed method has higher adaptability and intelligence. The proposed method is better than the classical image enhancement methods in overall performance. Enhanced typhoon cloud images by the proposed method can be used to accurately locate the center and predict intensity of the typhoon.

关键词： typhoon cloud image enhancement genetic algorithm fuzziness

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china Ocean engineering 1995年第4期10卷 365-374页

作者： Zhao Deting Senior Engineer, china Offshore Oil Development and engineering Corporation, Beijing 10002.

Based on some mechanical principles, this paper presents a new way for simplifying the tower structure on the platform, i. e., substituting the three-dimensional tower structure by using beam elements. For the overall analysis of offshore platform, this method can not only save man- power and computer time, but also get better results. This paper introduces the equivalent-simplifying method and its application in engineering.

关键词： tower structure equivalent-simplifying beam element offshore platform

System Identification of Bilinear State-space Models by Modified Gradient Search Method

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System Identification of Bilinear State-space Models by Modi...

Size and support effects for CO oxidation on supported Pd catalysts

第二十九届中国控制会议

作者： ZHONG Lusheng 1,2.FAN Xiaoping 1,YANG Hui 2.1.college of Information Science and engineering,Central South University,Changsha 41008{2.P.R.china2.college of Electrical and Electronic engineering,East china Jiaotong University,Nanchang Jiangxi {2.001{2.P.R.china

The problem of estimating parameter of bilinear state-space system is considered in this paper.A gradient based search algorithm is proposed to the optimization of output error cost *** nonuniqueness of the fully parameterized bilinear state-space is considered and the parameter update is restricted to the directions that are perpendicular to the manifold of input-output equivalent *** addition,the convergence rate is also ***,numerical simulation is implemented and the results show the improved performance of the proposed method.

关键词： System Identification Parameter Estimation Nonlinear Least Square Bilinear State-Space Model

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Science china Chemistry 2010年第9期53卷 2047-2056页

作者： WANG ZhaoWen,LI Bin,CHEN MingShu,WENG WeiZheng & WAN HuiLin State Key Laboratory of Physical Chemistry of Solid Surfaces National engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters Department of Chemistry,college of Chemistry and Chemical engineering,Xiamen University,Xiamen 3.1005,{3. 1. State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen University Xiamen 361005 China2. National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters Xiamen University Xiamen 361005 China3. Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

Supporting Pd catalysts characterized significant different size distribution were obtained using PdCl2.[Pd(NH3.4](NO3.2.and Pd(acac)2.as ***-resolution transmission electron microscopy(TEM),X-ray diffraction(XRD),in-situ Fourier transform infrared spectroscopy(FTIR) and Raman spectroscopy were used to examine the dispersion of *** performance measurements show that the activities for CO oxidation increase as the Pd particle size decreases and the O2.CO ratio *** activities under oxygen rich conditions are significantly higher than those at near the stoichiometric *** on TiO2.prepared by the Pd(acac)2.precursor is highly dispersed,leading to a considerable activity for CO oxidation at near room *** oxidation on the 1 wt% Pd/TiO2.and under an O2.CO ratio of 1 characterized an apparent activation energy of 3..7 kJ/mol,which is closed to those reported for CO oxidation on the supported Au *** present work demonstrates a high catalytic activity of highly dispersed noble metals,and suggests a promising approach of using noble metals as catalysts with exceeding high efficiency.

关键词： noble metals supported palladium CO oxidation size effect support effect