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71.
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The Internet is a set of interconnected domains in which different QoS technologies can be deployed. The dynamic provision of end-to-end QoS over heterogeneousip networks assumes the negotiation of mutually acceptablesla. This paper presents the concept of intra-, inter- and multiple-domain service level negotiation using thecops-sls protocol. The negotiation process gives different parties in the negotiation the ability to agree upon the service level that a data stream can obtain, along with the permissible pricing of the service.  相似文献   
73.
Good performance of optical coatings depends on the appropriate combination of optical and mechanical properties. Therefore, successful applications require good understanding of the relationship between optical microstructural and mechanical characteristics and film stability. In addition, there is a lack of standard mechanical tests that allow one to compare film properties measured in different laboratories. We give an overview of the methodology of mechanical measurements suitable for optical coatings; this includes depth-sensing indentation, scratch resistance, friction, abrasion and wear testing, and stress and adhesion evaluation. We used the techniques mentioned above in the same laboratory to systematically compare the mechanical behavior of frequently used high- and low-index materials, namely, TiO2, Ta2O5, and SiO2, prepared by different complementary techniques. They include ion-beam-assisted deposition by electron-beam evaporation, magnetron sputtering, dual-ion-beam sputtering, plasma-enhanced chemical-vapor deposition, and filtered cathodic arc deposition. The mechanical properties are correlated with the film microstructure that is inherently related to energetic conditions during film growth.  相似文献   
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75.
The introduction of full-body controllers has made computer games more accessible and promises to provide a more natural and engaging experience to players. However, the relationship between body movement and game engagement is not yet well understood. In this article, I consider how body movement affects the player's experience during game play. I start by presenting a taxonomy of body movements observed during game play. These are framed in the context of a body of previously published research that is then embedded into a novel model of engagement. This model describes the relationship between the taxonomy of movement and the type of engagement that each class of movement facilitates. I discuss the factors that may inhibit or enhance such relationship. Finally, I conclude by considering how the proposed model could lead to a more systematic and effective use of body movement for enhancing game experience.  相似文献   
76.
Networks-on-Chip (NoC) is an interesting option in design of communication infrastructures for embedded systems. It provides a scalable structure and balanced communication between the cores. Parallel applications that take advantage of the NoC architectures, are usually are communication-intensive. Thus, a big deal of data packets is transmitted simultaneously through the network. In order to avoid congestion delays that deteriorate the execution time of the implemented applications, an efficient routing strategy must be thought of carefully. In this paper, the ant colony optimization paradigm is explored to find and optimize routes in a mesh-based NoC. The proposed routing algorithms are simple yet efficient. The routing optimization is driven by the minimization of total latency during packets transmission between the tasks that compose the application. The presented performance evaluation is threefold: first, the impact of well-known synthetic traffic patterns is assessed; second, randomly generated applications are mapped into the NoC infrastructure and some synthetic communication traffics, that follow known patterns, are used to simulate real situations; third, sixteen real-world applications of the E3S and one specific application for digital image processing are mapped and their execution time evaluated. In both cases, the obtained results are compared to those obtained with known general purpose algorithms for deadlock free routing. The comparison avers the effectiveness and superiority of the ant colony inspired routing.  相似文献   
77.
The initial fouling rates of four crude oils were determined at a nominal bulk temperature of 315°C, an initial heated wall shear stress of 13 Pa, and initial surface temperatures between 375 and 445°C. These initial fouling rates ranged from 1.3(10? 6) to 7.8(10? 5) m2 K/kJ. Corresponding Arrhenius plots were linear with the initial fouling rates passing through an isokinetic temperature of 407.5°C. A plot of the natural logarithm of the pre-exponential factors [7.6(104)–5.2(1015) m2 K/kJ] versus the apparent activation energies (128–269 kJ/mol) was also linear, confirming the validity of the isokinetic temperature and the presence of the compensation effect. Below the isokinetic temperature, the relative fouling rates were Crude Oil C > Crude Oil A > Crude Oil D > Crude Oil B; above the isokinetic temperature, the relative fouling rates were reversed (Crude Oil B > Crude Oil D > Crude Oil A > Crude Oil C). Chemical characterization of a fouling deposit suggested that the dominant fouling mechanism at these conditions was coking, with significant contributions from sedimentation (iron sulfide) and corrosion (~ 340 μ m/yr) of the 304 stainless steel test material.  相似文献   
78.
Although beef tallow (BT) has been considered a hard low-trans fat convenient to be used in several bakery applications, it has some undesirable characteristics like fatty acid composition, crystallization behavior, graininess formation and poor plastic range. This work studied the modification of BT by blending at different percentages with high oleic sunflower oil (HOSFO) followed by the enzyme-catalyzed interesterification of the blends. The reduction in the solid fat content achieved by the simple blending was enhanced by the interesterification process, as a result of the increase in the concentration of the diunsaturated monosaturated type triacylglycerols. Interesterification strongly impacted too on the crystallization behavior of the blends, since products showed more homogeneous and regular crystals than the starting mixture. Results show that lipase catalyzed interesterification of BT with HOSFO offers a useful tool for the design of fats with adjustable physicochemical properties, improved with respect to that of the starting fats.  相似文献   
79.
We give a quadratic algorithm for the following structure identification problem: given a Boolean relation R and a finite set S of Boolean relations, can the relation R be expressed as a conjunctive query over the relations in the set S? Our algorithm is derived by first introducing the concept of a plain basis for a co-clone and then identifying natural plain bases for every co-clone in Post's lattice. In the process, we also give a quadratic algorithm for the problem of finding the smallest co-clone containing a Boolean relation.  相似文献   
80.
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