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71.
This paper evaluates the interplay between intentionality of stakeholders, organizational power and information systems (IS) implementation in the context of an European firm implementing an Enterprise Resource Planning system. We found that the implementation coincided with significant restructuring of power relations within the firm. We also found that the intentions of various stakeholders came to bear in terms of how organizational power got manifested. Our findings suggest a complex interplay between individual intentions and organizational power. Specifically, our study contributes to the literature by providing insights into the systemic nature of organizational power regarding IS implementations and how it relates to individual intentions.  相似文献   
72.
The Internet appears to being going through some kind of temper tantrum at the moment. Whether this is childish petulance, teenage rebellion, or some form of adult behaviour problem is difficult to decide, but there are definite signs of trouble out on the backbone.  相似文献   
73.
It is universally admitted that hydrogen is one of the best energy media and its demand will increase greatly in the near future. However, little hydrogen exists naturally, so that how to generate hydrogen without bringing forth much CO22 will be very important research subject. Hydrogen generation from water using nuclear energy is one of the solutions for this problem. Especially, the high temperature gas cooled reactor (HTGR) has a possibility to generate hydrogen economically compared with other types of nuclear reactors. As for long-lived radioactive waste to be generated by nuclear reactors, it is expected to significantly reduce its burden to the human environment by applying transmutation technologies. This report describes the feature of the hydrogen generation with HTGR and the development of the accelerator-driven subcritical system to reduce radioactive waste ongoing at JAEA.  相似文献   
74.
合成孔径雷达(Synthetic aperture radar,SAR)图像因为相干斑现象和目标响应的空间变化呈现出一种纹理特性,局部二进编码等局部图像特征 在光学纹理描述中获得较好的结果,但光学纹理特征在描述SAR图像纹理特性中因为相干成像特性往往失效. 本文 在前期工作纹理特征框架的基础上,提出了一种局部重要性采样二进编码的SAR图像纹理特征(Feature extraction based on local important sampling binary,LISBF)描述方法:首先,利用样本图像对局部采样位 置进行随机自适应采样,基于重要性采样(Important sample,IS)方法输出递归学习位置结果;然后,利用学习出的纹理重要采样点对进 行二进特征编码;最后,通过映射和统计生成描述算子. 该特征较固定位置采样能够获取更大范围信息,同时能通 过采样避免特征维数的急剧增大;通过自适应学习重要性关键点较随机采样 更容易捕捉纹理固有信息;较好地适应了SAR图像极低信噪比和斑点现象的纹理. 本文将该特征用于真实图像和标准纹理库的分类研究,实验结果证明了该特征的有效性.  相似文献   
75.
76.
利用Rough Set方法分析时间序列,已经取得了成果。时态信息系统(TIS)是时间序列的形式化表示。将时态信息系统转化为传统的信息系统(IS),是将Rough Set方法应用于时间序列挖掘的基础。目前,已有的将TLS转换为IS的方法,依赖于固定的时间间隔,具有一定的局限性。本文在已有算法的基础上,提出了两种改进方法,并结合Rough Set理论,使之适用于一般的时间序列的挖掘。  相似文献   
77.
Operability of Very High Temperature Reactor (VHTR) hydrogen cogeneration systems in response to abnormal transients initiated by the hydrogen production plant is one of the important concerns from economical and safety points of views. The abnormal events in the hydrogen production plant could initiate load changes and induce temperature variations in a primary cooling system. Excessive temperature increase in the primary cooling system would cause reactor scrams since the temperature increase in the primary cooling system is restricted in order to prevent undue thermal stresses from reactor structures. Also, temperature decrease has a potential propagation path for reactor scrams by reactivity insertions as a consequence of the reactivity feedbacks. Since suspensions of reactor operation and electricity generation should be avoided even in case of abnormal events in the hydrogen production plant from an economical point of view, an establishment of a control scheme against abnormal transients of hydrogen production plant is required for plant system design.In the present study, basic controls and their integration for the GTHTR300C, a VHTR cogeneration system designed by JAEA with a direct Brayton cycle power conversion unit and thermochemical Iodine-Sulfur process hydrogen production plant (IS hydrogen production plant), against abnormal transients of IS hydrogen production plant are presented. Transient simulations for selected load change events in the IS hydrogen production plants are performed by an original system analysis code which enables to evaluate major phenomena assumed in process heat exchangers of the IS hydrogen production plant.It is shown that abnormal load change events are successfully simulated by the system analysis code developed. The results demonstrated the technical feasibility of proposed controls for continuous operation of the reactor and power conversion unit against load change events in the IS hydrogen production plant.  相似文献   
78.
Organizations are exploring the potential of inter-organizational information systems (IS1s) in greater numbers. Generally the incentives are cost reduction and/or productivity improvement. Gaining these potential benefits requires cooperation within the information exchange path. Potential barriers, however, are the recognition of an information processing problem and the readiness to accept automated solutions.  相似文献   
79.
Ethical theory, codes of ethics and IS practice   总被引:1,自引:0,他引:1  
Ethical issues, with respect to computer-based information systems, are important to the individual IS practitioner. These same issues also have an important impact on the moral well-being of organizations and societies. Considerable discussion has taken place in the Information Systems (IS) literature on specific ethical issues, but there is little published work which relates these issues to mainstream ethical theory. This paper describes a range of ethical theories drawn from philosophy literature and uses these theories to critique aspects of the newly revised ACM Code of Ethics. Some in the IS field on problematic ethical issues which are not resolved by the Code are then identified and discussed. The paper draws some implications and conclusions on the value of ethical theory and codes of practice, and on further work to develop existing ethical themes and to promote new initiatives in the ethical domain.  相似文献   
80.
研究了利用低温等温凝固技术实现Cu-Sn键合在MEMS圆片级封装中的应用.基于Cu-Sn二元平衡相图,对键合层结构进行了设计,同时设计了用于测试的键合图形,并对设计的键合结构进行了流片实验.通过对圆片制作及键合等工艺的一系列优化,在250℃的低温条件下生成了熔点为415℃的金属间化合物,获得了良好的键合层.得到的键合样品剪切力强度值达到了GJB548B-2005标准的要求.研究表明,Cu-Sn等温凝固键合技术具有实际应用的潜力.  相似文献   
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