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51.
陈关荣 《数学建模及其应用》2013,2(1):7-11
简介了互联网的现状和结构以及互联网数学建模的历史和现状,并且实证比较了一些代表性网络模型的结构参数与功能表现。 相似文献
52.
Ellen?van?Berkel Nick?BoleyEmail author Steve?Ellison Jean-Claude?Libeer Irma?M?kinen Sverre?Sandberg Dan?Tholen Barry?Tylee Cas?Weykamp 《Accreditation and quality assurance》2006,11(8-9):446-450
Working group (WG) discussions on proficiency testing and external quality assessment held at the Eurachem workshop, Portorož, Slovenia 26–27 Sept 2005 are summarised. The discussions focused on performance criteria (WG 1), different aspects of accreditation (WGs 2–3), the revised international harmonised protocol (WG 4), pre- and post-analytical schemes (WG 5), Internet applications (WG 6), experience from the CoEPT project (WG 7), and future aspects (WG 8). Current status, problems and future directions were identified. The WG contained a mix of participants with different expertise. This was done to promote cross-fertilisation of ideas between sectors. The WG issues reflected the content of the keynote lectures and some issues were covered from different perspectives by more than one WG.Presented at the Eurachem PT Workshop September 2005, Portorož, Slovenia. 相似文献
53.
54.
如何浏览Internet上的化学信息资源 总被引:1,自引:0,他引:1
作为一个普通的化学工作者如何浏览Internet的上化学信息资源呢?笔者通过学习和实践,总结了几种方法。 相似文献
55.
卓仁杰 《宁波大学学报(理工版)》2005,18(2):276-278
详细介绍Internet上免费的毒理学数据库网站TOXNET所提供的毒理学文献数据库和其他事实数据库的功能、特点、检索方法和技巧. 相似文献
56.
Hanene Azzag Gilles Venturini Antoine Oliver Christiane Guinot 《European Journal of Operational Research》2007
In this paper is presented a new model for data clustering, which is inspired from the self-assembly behavior of real ants. Real ants can build complex structures by connecting themselves to each others. It is shown is this paper that this behavior can be used to build a hierarchical tree-structured partitioning of the data according to the similarities between those data. Several algorithms have been detailed using this model (called AntTree): deterministic or stochastic algorithms that may use or not global or local thresholds. Those algorithms have been evaluated using artificial and real databases. Our algorithms obtain competitive results when compared to the Kmeans, to ANTCLASS, and to Ascending Hierarchical Clustering. AntTree has been applied to three real world applications: the analysis of human healthy skin, the on-line mining of web sites usage, and the automatic construction of portal sites. 相似文献
57.
Internet的应用——介绍国外化学重点期刊网上投稿 总被引:3,自引:0,他引:3
介绍国外一些重要化学期刊的信息资源及其网址,重点介绍了如何进行网上投稿。 相似文献
58.
In this article, we consider mirror nodes, which are widely used to reduce local burden, and present two models that are practical for the Internet and probably some other networks. One model introduces an upper limit to the number of links that a node can have, beyond which the node will share the total links with a newly introduced one. Similarly, in the second model, if the number of links exceeds a limit, a new node will be introduced. Unlike the first model, the new node shares with the old one the chance of receiving new links but not the existing links. These models are analytically treated, and from the degree distribution, we can see that the number of nodes with medium links (half the upper limit) increases at the expense of the loss of highly connected nodes. By reducing the burden, this may improve the robustness of the networks. 相似文献
59.
本文应用量子方法和半经典方法计算了表征锂(6Li,7Li)原子和钾(39K,40K,41K)原子间超冷碰撞特性的散射参数,如s波散射长度,有效力程,p波散射长度等.超冷温度下6Li-39K单重态和三重态原子间的弹性散射截面主要为s波贡献,随着碰撞能量的增加散射截面有丰富的形状共振出现,计算发现单重态和三重态散射截面均存在显著的i波形状共振.此外,本文应用简并内态近似获得了超精细态相互作用时的s波散射长度. 相似文献
60.
On-line pseudo-dynamic network testing on base-isolated bridges using Internet and wireless Internet 总被引:2,自引:0,他引:2
D -U. Park C -B. Yun J -W. Lee K. Nagata E. Watanabe K. Sugiura 《Experimental Mechanics》2005,45(4):331-343
In this paper we present the results of the online pseudo-dynamic network testing using the Internet that were jointly conducted
by several institutions in Korea and Japan. Example studies were performed on base-isolated bridges with four continous spans.
Test facilities located at several institutions were interactively used to test the non-linear behaviors of the base isolators.
At first, a series of international network tests was carried out between Japan and Korea, and the performance of two system
configurations with different data communication schemes was compared. Then, network tests were repeated on a similar bridge
structure between two institutions in Korea, and the overall performance was discussed. A web-based Java monitoring system
was developed for checking the partners' testing conditions and for sharing the test results with the authorized observers.
Wireless Internet technology using mobile phones was also investigated. The results indicate that the time to execute a single
step varies widely, depending on the data communication/sharing schemes and the testing hardware, e.g., 0.2–15 s for data
communication and 1–10 s for execution of the pseudo-dynamic tests for each time-step. The time required additionally for
data communication in the on-line network testing is judged as reasonable in comparison with the time for the pseudo-dynamic
test. The results also show that the wireless communication is very attractive for on-line network testing, owing to the mobility
and Internet security. 相似文献