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51.
52.
提出了一种新的双簇头分簇算法,该算法在单簇头分簇算法的基础上增加了一个备用簇头节点,在簇头节点能量耗尽或出现故障时,备用簇头节点能够实时升成簇头节点以维持簇稳定工作,从而减少网络重建的次数,提後高网络稳定性,仿真实验表明,双簇头分簇算法比单簇头分簇算法有更好的稳定性和公平性. 相似文献
53.
V. R. Pai Verneker K. Kishore C. B. V. Subhas 《Propellants, Explosives, Pyrotechnics》1979,4(4):83-86
Thermal decomposition studies on double-base propellants have been carried out in air and vacuum using differential scanning calorimetric, thermogravimetric and mass spectrometric techniques. Low temperature (90 °C–170 °C) decomposition seems to involve diffusion controlled process, the mechanism in air and vacuum being different. High temperature (170 °–205 °C) decomposition involves bond breakage. 相似文献
54.
Due to pollution caused by the expansion of human activities and economic development, water quality has gradually deteriorated
in many areas of the world. Therefore, analysis of water quality becomes one of the most essential issues of modern civilization.
Integrated interdisciplinary modeling techniques, providing reliable, efficient, and accurate representation of the complex
phenomenon of water quality, have gained attention in recent years. With the ability to deal with both numeric and nominal
information, and express knowledge in a rule-based form, the Rough Set Theory (RST) has been successfully employed in many
fields. However, the application of RST has not been widely investigated in water quality analysis. The reducts generated
by RST models become very time-consuming as the size of the problem increases. Using multinomial logistics regression (MLR)
techniques to provide reducts of RST models, this investigation develops a hybrid Multinomial Logistic Regression and Rough
Set Theory (MLRRST) model to analyze relations between degrees of water pollution and environmental factors in Taiwan. Empirical
results indicate that the MLRRST model could analyze water qualities efficiently and accurately, and yield decision rules
for the staff of water quality management. Thus, the proposed model is a promising and helpful scheme in analyzing water quality. 相似文献
55.
56.
M. SureshA. Srinivasan K.R. RaviU.T.S. Pillai B.C. Pai 《Materials Science and Engineering: A》2011,528(6):2502-2508
Significant grain refinement in Mg-3Al alloy is achieved with the addition of charcoal due to the formation of Al4C3 particles, which act as effective nuclei for magnesium grains. Addition of 0.5 wt% charcoal has lead to reduced grain size of Mg-3Al alloy from 500 to 80 μm and no substantial grain refinement is obtained on further addition of charcoal. The results further reveal that the prolonged holding of the melt after the addition of charcoal has not affected the grain refining efficiency of Al4C3. Steady increase in tensile properties observed with increasing amount of charcoal addition has been attributed to the grain refinement and the presence of fine Al4C3 particles. The strengthening mechanisms due to charcoal addition are discussed in terms of Hall-Petch relation and dispersion strengthening. The predicted values are in good agreement with experimental results. 相似文献
57.
<正>我们如何构建高密度建筑的理论?社区的概念能否与这种大都市建筑契合?亦即,当建筑周边土地价格和空间成本十分高昂,以至于在某种程度上可以说每一寸土地都在为资本主义服务的时候,应该如何实现建筑和社区的概念?这些问题当然不甚鲜见。在战后美国、欧洲和日本经济扩张的背景下,路易·康、十人小组、阿 相似文献
58.
Yu. P. Besshaposhnikov V. E. Kozhevnikov V. I. Chernukhin V. V. Pai 《Combustion, Explosion, and Shock Waves》2002,38(1):119-122
Plate acceleration by a gliding detonation wave is studied experimentally for detonation rates of 950–2000 m/sec. It is found that regular elastic waves occur at the surface of the projectile plate made of a rather strong material, which disappear upon attainment of the upper limit of the detonation rate. 相似文献
59.
The early 1990s saw several announcements of commercial shared-memory systems using processors that aggressively exploited instruction-level parallelism (ILP), including the MIPS R10000, Hewlett-Packard PA8000, and Intel Pentium Pro. These processors could potentially reduce memory read stalls by overlapping read latency with other operations, possibly changing the nature of performance bottlenecks in the system. The authors' experience with Rsim demonstrates that modeling ILP features is important even in shared-memory multiprocessor systems. In particular, current simple processor-based approximations cannot model significant performance effects for applications exhibiting parallel read misses. Further, recent shared-memory designs such as aggressive implementations of sequential consistency use the aggressive ILP-enhancing features of modern processors that simple processor-based simulators do not model. As microprocessor systems become more complex, the availability of shared infrastructure source code is likely to become increasingly crucial. The authors plan to release a new Rsim version shortly that will include instruction caches, TLBs, multimedia extensions, simultaneous multithreading, Rabbit fast simulation mode, and ports to Linux platforms 相似文献
60.
Dinesh K.Pai 《Computer Graphics Forum》2002,21(3):347-352
Strands are thin elastic solids that are visually well approximated as smooth curves, and yet possess essential physical behaviors characteristic of solid objects such as twisting. Common examples in computer graphics include: sutures, catheters, and tendons in surgical simulation; hairs, ropes, and vegetation in animation. Physical models based on spring meshes or 3D finite elements for such thin solids are either inaccurate or inefficient for interactive simulation. In this paper we show that models based on the Cosserat theory of elastic rods are very well suited for interactive simulation of these objects. The physical model reduces to a system of spatial ordinary differential equations that can be solved efficiently for typical boundary conditions. The model handles the important geometric non‐linearity due to large changes in shape. We introduce Cosserat‐type physical models, describe efficient numerical methods for interactive simulation of these models, and implementation results. 相似文献