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M. Piraveenan M. Prokopenko A. Y. Zomaya 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,70(2):275-285
Local assortativity has been recently proposed as a measure to analyse complex networks. It has been noted that the Internet
Autonomous System level networks show a markedly different local assortativity profile to most biological and social networks.
In this paper we show that, even though several Internet growth models exist, none of them produce the local assortativity
profile that can be observed in the real AS networks. We introduce a new generic growth model which can produce a linear local
assortativity profile similar to that of the Internet. We verify that this model accurately depicts the local assortativity
profile criteria of Internet, while also satisfactorily modelling other attributes of AS networks already explained by existing
models. 相似文献
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Wei-Wen Wu Lawrence W. Lan Yu-Ting Lee 《European Journal of Operational Research》2012,218(1):230-238
The Global Information Technology Report released by the World Economic Forum (WEF) has employed networked readiness index (NRI) to measure the global competitiveness of a country’s information and communication technologies (ICT) diffusion. The final NRI overall scores were measured by an arithmetic mean aggregation of the composite pillars scores, which implicitly assumed that all the pillars have constant weights. The Report did not explore the critical pillars and causal relations for better decision making. To add values to this Report, the objective of this paper is to propose an innovative approach by using data mining techniques and partial least squares path modeling to scrutinize the critical pillars within the NRI and to further explore the causal relations amongst them. An empirical analysis based on the latest Report (2009-2010) is carried out. The results show that “business usage,” “business readiness,” and “market environment” are the three root drivers—critical pillars to manipulate the NRI overall scores; whereas “government readiness,” which is further mostly affected by the “government usage,” is the foremost enabler to the NRI overall scores. Based on the results, policy makers are suggested to allocate limited resources with priority to the three root drivers and one foremost enabler to frog-leap the global competitiveness of national ICT diffusion. 相似文献
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Persistent organic pollutants (POPs) are major environmental concern due to their persistence, long-range transportability, bio-accumulation and potentially adverse effects on living organisms. Analytical chemistry plays an essential role in the measurement of POPs and provides important information on their distribution and environmental transformations. Much effort has been devoted during the last two decades to the development of faster, safer, more reliable and more sensitive analytical techniques for these pollutants. Since the Stockholm Convention (SC) on POPs was adopted 12 years ago, analytical methods have been extensively developed. This review article introduces recent analytical techniques and applications for the determination of POPs in environmental and biota samples, and summarizes the extraction, separation and instrumental analyses of the halogenated POPs. Also, this review covers important aspects for the analyses of SC POPs (e.g. lipid determination and quality assurance/quality control (QA/QC)), and finally discusses future trends for improving the POPs analyses and for potential new POPs. 相似文献
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Teles FS 《Analytica chimica acta》2011,(1):28-42
The past decades have witnessed enormous technological improvements towards the development of simple, cost-effective and accurate rapid diagnostic tests for detection and identification of infectious pathogens. Among them is dengue virus, the etiologic agent of the mosquito-borne dengue disease, one of the most important emerging infectious pathologies of nowadays. Dengue fever may cause potentially deadly hemorrhagic symptoms and is endemic in the tropical and sub-tropical world, being also a serious threat to temperate countries in the developed world. Effective diagnostics for dengue should be able to discriminate among the four antigenically related dengue serotypes and fulfill the requirements for successful decentralized (point-of-care) testing in the harsh environmental conditions found in most tropical regions. The accurate identification of circulating serotypes is crucial for the successful implementation of vector control programs based on reliable epidemiological predictions. This paper briefly summarizes the limitations of the main conventional techniques for biomolecular diagnosis of dengue disease and critically reviews some of the most relevant biosensors and rapid diagnostic tests developed, implemented and reported so far for point-of-care testing of dengue infections. The invaluable contributions of microfluidics and nanotechnology encompass the whole paper, while evaluation concerns of rapid diagnostic tests and foreseen technological improvements in this field are also overviewed for the diagnosis of dengue and other infectious and tropical diseases as well. 相似文献
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科幻文学并非单纯的通俗文学,具有严肃的一面。中国科幻文学的发展困境源于中国科幻缺乏科学精神。《科幻世界》和其主要作家群的发展与流变反映出杂志自身理念上的范式转换,也反映出严肃的科幻文学在逐渐走向商品化和大众化,这是100年来人文关怀的衰落所导致的。中国的幻想文学应当有严肃的文化操守。 相似文献
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上海世博会影响力的定量评估 总被引:1,自引:0,他引:1
2010年上海世博会的成功举办,对我国影响很大,而且涉及方面很广,采用大家比较重视的旅游业这一侧面做为切入点,选择能很好的反映旅游业状况的入境旅游人数,根据近30年上海入境旅游人数的相关数据,建立曲线模型预测在自然状态下2010年世博会期间的入境旅游人数.用预测值与实际值对比,反映出世博会的影响力将持续85年. 相似文献
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Lawrence Badash 《Physics in Perspective (PIP)》2005,7(2):138-149
Social responsibility in science has a centuries-long history, but it was such a minor thread that most scientists were unaware of the concept. Even toward the conclusion of the Manhattan Project, which produced the first nuclear weapons, only a handful of its participants had some reservations about use of a weapon of mass destruction. But the explosions over Hiroshima and Nagasaki not only made society more aware of the importance of science, they made scientists more aware of their responsibility to society. I describe the development of the concept of social responsibility and its appearance among American scientists both before and after the end of World War II.Expanded version of a talk in Hiroshima, Japan,August 10, 2003.Lawrence Badash is Professor Emeritus of History of Science at the University of California, Santa Barbara. 相似文献