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Document caching and connection caching are extensively studied problems. In document caching, one has to maintain caches containing documents accessible in a network. In connection caching, one has to maintain a set of open network connections that handle data transfer. Previous work investigated these two problems separately while in practice the problems occur together: In order to load a document, one has to establish a connection between network nodes if the required connection is not already open. In this paper we present the first study that integrates document and connection caching. We first consider a very basic model in which all documents have the same size and the cost of loading a document or establishing a connection is equal to 1. We present deterministic and randomized online algorithms that achieve nearly optimal competitive ratios unless the size of the connection cache is extremely small. We then consider general settings where documents have varying sizes. We investigate a FAULT model in which the loading cost of a document is 1 as well as a BIT model in which the loading cost is equal to the size of the document.  相似文献   
63.
The effect of cyclic stressing on the strength of single lap adhesive joints has been studied and a considerable reduction in strength observed when the maximum stress exceeds about 40% of the ultimate tensile strength, but whether or not a true endurance limit exists is not proven. Fallacies are shown in some of the techniques which have been proposed for studying the fatigue behaviour of adhesive joints.  相似文献   
64.
Excessive power supply noise during test can cause overkill. This article discusses two models for supply noise in delay testing and their application to test compaction. The proposed noise models avoid complicated power network analysis, making them much faster than existing power noise analysis tools. can cause performance degradation and  相似文献   
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Zusammenfassung  Aus der Sicht eines informationstechnischen Laien scheinen Denial of Service-Angriffe mit Online-Demonstrationen in keinem Zusammenhang zu stehen. Das Gegenteil ist der Fall, wenn durch derartige Angriffe der Anbieter einer Webseite buchst?blich lahm gelegt wird. Ob die an sich lautere Intention einer kritischen Meinungs?u?erung derartige Angriffe rechtfertigen kann, ist fraglich und besch?ftigt die Justiz. Der Verfasser dieses Beitrages bewertet den Sachverhalt eines Denial-of-Service-Angriffes strafrechtlich. Dr. jur. Jan Eichelberger, LL.M.oec. Rechtsreferendar am Kammergericht Interessenschwerpunkte im Gewerblichen Rechtsschutz, im Kapitalmarktrecht und im Recht der neuen Medien  相似文献   
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This work discusses the potential of three multistage zeolite drying systems (counter-, co-, and cross-current) with a varying number of stages. The evaluation showed that for 2-4 stages with heat recovery the efficiency of the systems ranges between 80 and 90%. Additionally, by introducing a compressor, the latent heat in the exhaust air from the regenerator is recovered and used to heat the inlet air for an additional drying stage. As a result, for the counter-current drying system and compressor pressure 1.5-2 bar, a maximum energy efficiency of 120% is achieved, which results in halving the energy consumption compared to conventional drying systems.  相似文献   
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This paper presents a new approach to the blind deconvolution and superresolution problem of multiple degraded low-resolution frames of the original scene. We do not assume any prior information about the shape of degradation blurs. The proposed approach consists of building a regularized energy function and minimizing it with respect to the original image and blurs, where regularization is carried out in both the image and blur domains. The image regularization based on variational principles maintains stable performance under severe noise corruption. The blur regularization guarantees consistency of the solution by exploiting differences among the acquired low-resolution images. Several experiments on synthetic and real data illustrate the robustness and utilization of the proposed technique in real applications.  相似文献   
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An unpackaged microchip is used as the sensing element in a miniaturized gaseous proportional chamber. This letter reports on the fabrication and performance of a complete radiation imaging detector based on this principle. Our fabrication schemes are based on wafer-scale and chip-scale postprocessing. Compared to hybrid-assembled gaseous detectors, our microsystem shows superior alignment precision and energy resolution, and offers the capability to unambiguously reconstruct 3D radiation tracks on the spot.  相似文献   
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