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32.
键级和化合价的分子轨道理论   总被引:1,自引:0,他引:1  
本文译自美国《Journal of chemical Education》1988年第8期.作者简介了密立根布居数分析法,并以此为基础讨论了键级和化合价,应用了别致的原子轨道线性组合分子轨道理论(LCAO—MO)的矩阵公式.最后给出了一些简单分子的计算结果,以说明这个理论的应用.  相似文献   
33.
浅谈现代健美操的健、力、美   总被引:1,自引:0,他引:1  
本文从编排和训练的角度,详细论述了健美操的三个核心要素——健、力、美,并指出了影响健美操效果的各种因素,以及健美操中音乐的“灵魂作用”、操与舞的关系、形体美与心灵美的关系等等,为广大健美操工作者及爱好者提供了健美操编排及训练的理论依据。  相似文献   
34.
The Franklin Institute, Philadelphia, Pennsylvania awarded the 2001 Benjamin Franklin Medal in Life Science to Judah Folkman for his founding of the field of angiogenesis research and demonstration that angiogenesis is a necessary factor in the conversion of abnormal cells to malignant tumors.  相似文献   
35.
Although often downplayed and instrumental, there is evidence that communication in projects is essential in achieving value creation. Our main interest in this paper is on temporary continuity, a situation where the temporary becomes a permanent condition in social systems. The question that we have address is: What characterizes project communication in a situation with temporary continuity?We argue for the need to transform communication processes into communication capabilities. In a situation with temporary continuity, there is a need to connect to a large number of value-creating processes, and communicating capabilities need to be a part of a communication system, where the aim is to bind together value-creating processes and communication capabilities. We construct a viable system consisting of five sub-systems. To become a viable system, projects in the form of temporary continuity, must handle the potential conflict between a culture of performance and a culture of innovation. This involves developing social mechanisms for coordination and interaction, with a focus on developing communication capabilities, in parallel with focusing on all of the five value-creation processes.  相似文献   
36.
The Franklin Institute, Philadelphia, Pennsylvania, awarded the 2001 Benjamin Franklin Medal in Earth Science to Rob Van der Voo for his outstanding contributions to the field of paleomagnetism and his reconstruction of ancient continental positions that have lead to a better understanding of plate tectonic processes for the past billion years of Earth history.  相似文献   
37.
U.S. federal websites are required to be accessible for people with impairments. However, despite the existing regulations and guidelines, many federal websites continue to be inaccessible, and accessibility policy statements available on federal websites often do not provide any useful information. This paper provides three contributions to the research literature: (1) an accessibility evaluation of 100 federal home pages using both human and automated methods, (2) a content analysis of existing website accessibility policy statements, and (3) a discussion of the relationship between actual Section 508 compliance and the existing accessibility policy statements on a website. The paper concludes with recommendations for improving policy related to Section 508 compliance for websites.  相似文献   
38.
The web visibility of politicians has substantial implications for the internet and politics. In this regard, the present paper examines the web visibility of South Korea's 18th National Assembly members. This study identifies those members with the highest web visibility and determines the factors affecting their web visibility by using a set of socio-demographic variables indicating web visibility. The concept of web visibility is operationally defined as the number of web mentions of each congressional member. Web mentions of the name of each congressional member were collected across many platforms, including blogs, images, news, and websites, by using a Naver search tool based on the API, and relationships between the web visibility of the members and their socio-demographic attributes (their gender, age, term, constituency, and party affiliation) were analyzed using Kruskal–Wallis, Median, and Mann–Whitney U tests. The most visible politicians in the Korean webosphere had highly qualified political careers and prominence, and the difference in politicians' web visibility depended on their political attributes (their term, constituency, and party), not on their demographic attributes (their gender and age). These findings suggest that politicians who build political power and influence through their political career in the offline world are likely to be more visible in the webosphere. Further, an integrated indicator based on politicians' web visibility status can reflect their “ubiquitous presence” in Korea's digitalized society.  相似文献   
39.
E-Government has received significant attention as digital technologies transcend private businesses and serve as a basic source of transformation in government functions. One most notable project is the United Nations Public Administration Network (UNPAN) that assesses the e-Government readiness of the 192 member nations according to a quantitative composite index involving website assessment, telecommunication infrastructure, and human resource endowment. However, the UNPAN index, though rich in depth and breadth of data collection, relies on a method that is a simple mathematical average of the values of the variables measured. This paper revisits the UNPAN index and proposes alternative indices based on principal components analysis (PCA). Using the UNPAN survey data, four different versions of the index are presented and the resulting rankings of the nations are examined vis-à-vis the existing ranking. The theoretical and policy implications of the proposed methodology and its results are discussed.  相似文献   
40.
Assessing e-government responsiveness is one of the major gaps in the currently dominant e-government maturity models. While we have a relatively large pool of models focusing on technological and organizational integration from a supply side perspective, measures of responsiveness of e-government systems from a user perspective are still lacking. Replicating a study from New Zealand and Australia, this study explores the response time and quality of e-mail response in Danish local and central governments (N = 175). Despite that Denmark is high ranking in international benchmark studies, we find that one third of central government agencies did not respond at all, and close to 80% of the ministries provided none or incomplete answers. Local government responds faster and provides answers that are more complete and accurate than those provided by central government. Implications for e-government are discussed.  相似文献   
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