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101.
相似度量是图像检索的关键,EMD是一种有效的度量距离,但其计算比较复杂,而且赖于基本距离的选择。采用Lloyd聚类算法对图像进行高斯混合建模,并以聚类失真作为基本距离提出了两种近似EMD的方法计算相似度。实验结果验证了该方法的有效性,其检索效率与EMD方接近,而且计算复杂度比EMD方法低,基本距离的选择不敏感。 相似文献
102.
We adapted a model in organizational theory to determine whether organizational citizenship behaviors (OCBs) of system implementation teams influenced that organization's integration climate and improved their project management, resulting in successful system implementation. Surveys were elicited from 254 system users in various business organizations that had implemented large-scale IS in the previous year; the analysis of their responses provided support for our model, suggesting that the OCB of the implementation team created a higher level of integration climate and more effective project management, and that these in turn influenced information system success. Implications for researchers and managers are discussed and limitations are identified. 相似文献
103.
Although there have been a number of studies of the determinant factors of Electronic Data Interchange (EDI) implementation, most studies were carried out in the United States or Europe. The purpose of this study is to identify the determinant factors which affect implementation of EDI systems by Korean companies. Decentralization, EDI standards, technical compatibility, technical support by EDI vendors, education and training and participation of trading partners positively affect the extent of EDI usage. Formalization, technical compatibility, user involvement and participation of trading partners affect EDI integration with internal applications. Top management support and the participation of trading partners promote the extent of EDI operations. This study provides evidence of the effect of important determinant factors such as participation of trading partners and technical compatibility replicating previous EDI studies conducted in that US and Europe. For policy makers ad EDI developers, this study provides insights as to appropriate measures and incentives system designed to encourage EDI and B2B implementation. 相似文献
104.
以创新扩散理论与文献为依据构建了企业电子商务采纳与应用关键影响因素模型,并以长三角地区企业为主体进行了问卷调查。在利用SPSS对调查结果进行信度分析的基础上,采用结构方程模型对假设模型进行了实证,研究结论有助于企业认清自身所处的环境与条件,了解电子商务技术采纳行为形成的机理,有效管理电子商务技术采纳与应用活动。 相似文献
105.
This study was designed to answer several key questions regarding the service injustice customers perceived during the service delivery. Using the critical incident technique, the authors collected 195 unfair incidents from a variety of service organizations. The initial sorting of the incidents resulted in four major groups: information asymmetry, unfair procedure, inappropriate attitudes and manners of the service personnel, and unfair outcomes. Within the four major classifications of critical incidents, 13 secondary categories were identified. A further analysis was conducted to discover the underlying reason why customers feel unfair in the service encounters. Finally, some implications for service managers were discussed. 相似文献
106.
基于MATLAB/Simulink的PID参数整定 总被引:4,自引:0,他引:4
针对PID参数整定过程的复杂性,基于MATLAB/Simulink仿真环境,模拟临界比例度法PID参数整定的方法和步骤,给出了一种简单有效的PID参数整定方法。与通常的整定方法比较,其优点是非常直观、可以随意修改仿真参数,节省了大量的计算和编程工作量。通过仿真实例验证了该方法的有效性。 相似文献
107.
为了系统地确定软件测试性影响因素,提出一种基于因果图的分析方法.方法首先确定软件类型,分析软件特点;接着确定测试性的具体表现形式,通过对具体形式的原因分析构造因果图,分析因果图中的最小因素;最后整理出影响因素.方法能全面、系统地得到测试性影响因素,对嵌入式软件的成功分析表明了方法的可行性. 相似文献
108.
胡春艳 《数码设计:surface》2009,(6):163-165
工业设计就是信息为主导的行业:设计师要分析现存事物和设备的状态然后设计出更为优越的产品。因而信息技术的革命对产品设计的过程带来了重大的影响,我们有必要对信息技术所取得的成就做出评估。此文将探讨这一新兴技术中的新潮流。信息技术所带来的新潮流包括:产品的情感要素的强化,人与产品和界面的情景交融中产生感情互动的趋势,艺术的创造方法成为产品创新和产品设计与互联网紧密结合。 相似文献
109.
周继平 《数码设计:surface》2009,(11):193-195
要使完全没有色彩知识与造型意识的高等职业学校的学生,在不多的色彩课时计划内比较全面地了解和初步掌握色彩的基本表现技法,授课教师不但要有较深的色彩理论知识和过硬的色彩造型功底,还必须具有灵活多样的教学方法与实训指导技巧,更需要进行强化有效的实训教学手段。 相似文献
110.
A. Z. Panagiotopoulos 《International Journal of Thermophysics》1994,15(6):1057-1072
Abstact The subject of this paper is the investigation of finite-size effects and the determination of critical parameters for a class of truncated Lennard-Jones potentials. Despite significant recent progress in our ability to model phase equilibria in multicomponent mixtures from direct molecular simulations, the accurate determination of critical parameters remains a difficult problem. Gibbs ensemble Monte Carlo simulations with systems of controlled linear system size are used to obtain the phase behavior in the near-critical region for two- and three dimensional Lennard-Jones fluids with reduced cutoff radii of 3, 3.5, and 5. For the two-dimensional systems, crossover of the effective exponent for the width of the coexistence curve from mean field ( = 1/2 in the immediate vicinity of the critical point to Ising-like (= 1/8) farther away is observed. Critical parameters determined by fitting the data that follow Ising-like behavior are in good agreement with literature values obtained with finite-size scaling methods. For the three-dimensional systems, no crossover to mean field-type behavior was apparent. Extrapolated results for the critical parameters are consistent with literature estimates for similar fluids. For both two- and three-dimensional fluids, system size effects on the coexistence curves away from the critical point are small, normally within simulation statistical uncertainties.Invited paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24, 1994, Boulder. Colorado, U.S.A. 相似文献