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1.
The estimation of the link capacity and its available bandwidth in an end-to-end path is crucial for network management, admission
control and flow control for adaptive applications. This paper introduces an estimation mechanism able to accurately estimate
the available bandwidth of all links in an end-to-end path, through its capacity and cross-traffic estimation. The estimation
procedures resort to the dispersions of packet pairs and trains using the concepts of ICMP Timestamp and Traceroute that,
efficiently used together, enable the measurement of the dispersions in all links in the path. These mechanisms were evaluated
through simulation experiments, where we analyzed the influence of the several network parameters on each estimation mechanism.
The results show that these estimation methods are able to accurately estimate both the capacity and the cross-traffic of
all links in a path with moderate length and with low overhead. 相似文献
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阐述了视觉符号语言在版面设计中的编码与各种表现形式,强调信息社会的来临,以视觉为形态的符号语言将有效加速信息的传递。 相似文献
5.
Astrid Labidi Marie-Christine Salon Alessandro Gandini Hervé Cheradame 《Polymer Bulletin》1985,14(3-4):271-278
Summary 2-Furyl vinyl ketone was polymerised using anionic, cationic and free-radical initiators. Yields and molecular weights varied with the type of activation. Whereas radical polymerisation gave a product possessing a regular vinylic structure, other kinds of units were detected in the polymers prepared with anionic and cationic catalysts. 相似文献
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7.
We compare two link analysis ranking methods of web pages in a site. The first, called Site Rank, is an adaptation of PageRank to the granularity of a web site and the second, called Popularity Rank, is based on the frequencies of user clicks on the outlinks in a page that are captured by navigation sessions of users through
the web site. We ran experiments on artificially created web sites of different sizes and on two real data sets, employing
the relative entropy to compare the distributions of the two ranking methods. For the real data sets we also employ a nonparametric
measure, called Spearman's footrule, which we use to compare the top-ten web pages ranked by the two methods. Our main result
is that the distributions of the Popularity Rank and Site Rank are surprisingly close to each other, implying that the topology
of a web site is very instrumental in guiding users through the site. Thus, in practice, the Site Rank provides a reasonable
first order approximation of the aggregate behaviour of users within a web site given by the Popularity Rank. 相似文献
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川西平原属沉积平原,不到2m厚的表土下面全是沙卵石,沙卯石厚度达二、三十米。地面覆盖农田,沟垄纵横,限制了车载钻机的进入。以往地震勘探多采取浅井组合方式激发,所获得的地震资料能量差、面波强,对农田破坏面积大。若使用SH30—2A型轻便工程钻机,配上自制的冲击管,采取冲击钻进,从管中下药柱的方式,可实现沙卵石地区的深井激发,提高资料采集质量,且效率高、成本低。 相似文献
10.
Sebastián López Gustavo M. Callicó Félix Tobajas Valentín de Armas José F. López Roberto Sarmiento 《ETRI Journal》2008,30(6):862-864
This letter presents a novel approach for organizing computational resources into groups within H.264/AVC motion estimation architectures, leading to reductions of up to 75% in the equivalent gate count with respect to state‐of‐the‐art designs. 相似文献