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991.
Jianzhong Qi Rui Zhang Yanqiu Wang Andy Yuan Xue Ge Yu Lars Kulik 《World Wide Web》2014,17(6):1261-1293
We propose and study a new type of location optimization problem, the min-dist location selection problem: given a set of clients and a set of existing facilities, we select a location from a given set of potential locations for establishing a new facility, so that the average distance between a client and her nearest facility is minimized. The problem has a wide range of applications in urban development simulation, massively multiplayer online games, and decision support systems. We also investigate a variant of the problem, where we consider replacing (instead of adding) a facility while achieving the same optimization goal. We call this variant the min-dist facility replacement problem. We explore two common approaches to location optimization problems and present methods based on those approaches for solving the min-dist location selection problem. However, those methods either need to maintain an extra index or fall short in efficiency. To address their drawbacks, we propose a novel method (named MND), which has very close performance to the fastest method but does not need an extra index. We then utilize the key idea behind MND to approach the min-dist facility replacement problem, which results in two algorithms names MSND and RID. We provide a detailed comparative cost analysis and conduct extensive experiments on the various algorithms. The results show that MND and RID outperform their competitors by orders of magnitude. 相似文献
992.
Traditional Byzantine consensus in distributed systems requires n ≥ 3f + 1, where n is the number of nodes. In this paper, we present a scalable and leaderless Byzantine consensus implementation based on gossip, requiring only n ≥ 2f + 1 nodes. Unlike conventional distributed systems, the network topology of cloud computing systems is often not fully connected, but loosely coupled and layered. Hence, we revisit the Byzantine consensus problem in cloud computing environments, in which each node maintains some number of neighbors, called local view. The message complexity of our Byzantine consensus scheme is O(n), instead of O(n 2). Experimental results and correctness proof show that our Byzantine consensus scheme can solve the Byzantine consensus problem safely in a scalable way without a bottleneck and a leader in cloud computing environments. 相似文献
993.
Guofeng Zhao Minchang Yu Chuan Xu Hong Tang 《通讯和计算机》2014,(1):59-65
Generating web traffic is of great importance to analyze performance of new designed network, test new equipment, and verify new protocols, etc.. However, most existing traffic generation systems tend to simulate the overall characteristics of network traffic, while neglecting of the behavior of the individual users. Nevertheless, in principle, the emerged characteristics of overall traffic originate from the aggregation of individual users' access behavior. In this paper, we propose an innovative web traffic generating method based on user browsing behavior. Our method simulates the real users' accessing behavior, and visits the real web servers. Then, we design and develop a web traffic generating system. Because our system accesses the real websites, it can produce almost the real network traffic. The test results show that the traffic generated by our system has characteristics of burstiness and self-similarity, which are widely found and characterized in many real networks. In addition, our system can better reflect real user's web browsing behavior. 相似文献
994.
4G时代的到来给智能电视行业带来了极大的变革.如何有效利用4G技术,迎接新技术带来的机遇和挑战,成为智能电视企业发展的重要课题.结合4G技术发展带来的行业变革,调查了智能电视商业模式现状,并有针对性地提出了智能电视商业模式的发展措施. 相似文献
995.
996.
Conclusions Breaking loads and deformation properties of complex viscose yarns containing elementary filaments of different linear density have been studied.The change in structural nonuniformity over a cross-section of viscose textile filaments of different linear density has been quantitatively evaluated.Translated from Khimicheskie Volokna, No. 3, pp. 47–48, May–June, 1985. 相似文献
997.
998.
G. É. Solovushkova Yu. A. Polonskii I. Ya. Dol'nikov N. K. Arkhipova V. V. Kolomeitsev D. B. Min'kov B. V. Parkhaev 《Refractories and Industrial Ceramics》1980,21(7-8):333-334
Conclusions A technology was developed for stabilizing quartz slip for making immersion sheaths at the Podolsk refractories factory using electrolytes, enabling us to reduce the slip preparation time by 19–22 h, reducing its viscosity with a reduction in the water content from 22 to 17–20%, reducing the loss of greenware. In the conditions of KTs-2 of the Novolipetsk plant, the experimental nozzles showed a resistance similar to that of nozzles obtained by the traditional method used at Podolsk.Translated from Ogneupory, No. 7, pp. 5–6, July, 1980. 相似文献
999.
Conclusion We have attempted to analyze the synthesis of the diamond phase during, the detonation of secondary explosives by comparing the results of an explosion experiment with data obtained by studying preserved UDD powders.These data show that during detonation the growth in the UDD particles is a strongly limited process that is essentially independent of the size of the explosive charge or the external cooling conditions. The size distributions of diamond particles formed during direct synthesis from the carbon contained in the molecular structure of the explosive and during dissociation of inert organic substances are in satisfactory agreement with a lognormal distribution. The thermodynamic conditions during synthesis determine the dispersivity of the product UDD particles and this must be taken into account in thermodynamic detonation calculations. The effect of the different constituents of the, explosive on UDD synthesis (heat and mass transfer) is strongly limited.These data may support the concept of detonation in secondary explosives as a set of relatively fast and much slower reactions [25, 26] where, in the case of composites, the coagulation of carbon released during decomposition of each component separately and diffusion processes among the components may both act as slow exothermic reactions.Novosibirsk. Translated from Fizika Goreniya i. Vzryva, Vol. 29, No. 1, pp. 120–128, January–February, 1993. 相似文献
1000.