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并行程序设计是并行计算的难点之一,基于模式的并行程序设计方法为程序员提供了并行程序的框架,比使用并行库(PVM和MPI)具有更高的抽象程度和通用性。本文简单地介绍了目前国际上三种应用此方法所开发的模型或项目以及我们所研究的SRVRT模型,并做出了比较。 相似文献
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《Journal of Cultural Heritage》2014,15(2):128-135
Many whale (baleen whale or toothed whale) skeletons still contain residual lipids even after an initial osteological preparation. This paper examines the different possibilities of re-treatment. Before a conservation intervention, it was necessary to determine the materials of which bones are made up. The samples were analyzed by Raman spectroscopy. Different compounds were identified: a mineral part (apatite), an organic part (collagen) and lipids. Chromatography analysis yielded a detailed composition of the lipids. It was in fact degraded fat with saturated and unsaturated fatty acids. To remove these lipids, several techniques were identified and tested: enzymatic treatments, supercritical CO2, and green or organic solvents. Esterification catalyzed by lipases could be suitable for a degreasing treatment since the solubility of esters is higher than that of the corresponding fatty acids. The enzymatic treatment acted only on the surface and did not appear to be very efficient. The use of supercritical CO2 was even less effective. Some green solvents can partially extract lipids but prove difficult to eliminate after treatment. The best results for degreasing were achieved using organic solvents. Different solutions were evaluated at hot or ambient temperature and in simple immersion or with agitation (Soxhlet or pulsed pressure): hexane, heptane, a mixture of hexane/isopropanol, or an azeotropic mixture of methanol/chloroform. Only the mixture of methanol/chloroform succeeded in extracting the overall fat content, but this treatment degraded the organic part of the bones. The other organic solvents extracted mainly colored fat, which generally corresponded to a weight loss of 20 to 50%. The majority of fat was extracted during the first bath. Thus the treatment selected is that of immersion in heptane at ambient temperature. The degreasing of whole bones is less effective because of the film of sticky degraded fat on the bone's surface. A pre-cleaning is necessary to eliminate this film. 相似文献
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以铁盐和l,3,5-均苯三甲酸为原料,按照一定的配比在不同的溶剂中合成一系列铁骨架配合物凝胶,并进行SEM和红外光谱（IR）表征;以吡啶和苯硼酸的suzuki-Miyaura交叉偶联反应及苯乙炔和芳烃的加成反应为例,研究铁骨架配合物凝胶催化性能。结果表明,以合成的铁骨架配合物凝胶作催化剂,反应产率高,廉价且绿色环保,无需昂贵的配体、强碱环境、高温及气体氛围等条件。 相似文献
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SONG Chao ZHANG Hong-xin HUANG Jin BAO Hu-jun 《浙江大学学报(A卷英文版)》2006,7(9):1596-1602
INTRODUCTION Physical simulation is an important area for creating realistic character animations. In the film industry, animators require detailed control of the motion of their characters. Many techniques have been developed for automatically simulating charac- ters’ motion. The skeleton driven elastic deformation is paid much attention in these techniques, since many motions and deformations in character animations are mainly driven by skeleton. In general, however, it is not easy to … 相似文献
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杜洁 《河北体育学院学报》2010,24(2):87-90
测定了石家庄市成年人的肥胖发生率,探讨了身高和胯宽比与体脂百分比之间的关系,并计算出其相关度,旨在为超重和肥胖的重新界定提供新的依据,并为大众健身提供理论指导。 相似文献
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九华山金地藏信仰中,费冠卿所说"经云:菩萨钩锁、百骸呜矣"其实有着深厚的经典依据,但长期以来未深入探考。实际上佛典中对从凡夫到至诸象狮及十住菩萨与佛的骨骸结构与力量大小有一套说法,亦说骨骸声鸣能反映其五趣六道所在。这些经典说法对灵验故事僧俗传记都产生了影响,在金地藏信仰中也起到重要作用。 相似文献
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简要分析了嵌入式Linux下的硬件驱动程序结构,研究了Linux下的USB骨架驱动程序,具备很强的实用性。 相似文献
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In the present work we perform compressed pattern matching in binary Huffman encoded texts [Huffman, D. (1952). A method for the construction of minimum redundancy codes, Proc. of the IRE, 40, 1098–1101]. A modified Knuth–Morris–Pratt algorithm is used in order to overcome the problem of false matches, i.e., an occurrence of the encoded pattern in the encoded text that does not correspond to an occurrence of the pattern itself in the original text. We propose a bitwise KMP algorithm that can move one extra bit in the case of a mismatch since the alphabet is binary. To avoid processing any bit of the encoded text more than once, a preprocessed table is used to determine how far to back up when a mismatch is detected, and is defined so that we are always able to align the start of the encoded pattern with the start of a codeword in the encoded text. We combine our KMP algorithm with two practical Huffman decoding schemes which handle more than a single bit per machine operation; skeleton trees defined by Klein [Klein, S. T. (2000). Skeleton trees for efficient decoding of huffman encoded texts. Information Retrieval, 3, 7–23], and numerical comparisons between special canonical values and portions of a sliding window presented in Moffat and Turpin [Moffat, A., & Turpin, A. (1997). On the implementation of minimum redundancy prefix codes. IEEE Transactions on Communications, 45, 1200–1207]. Experiments show rapid search times of our algorithms compared to the “decompress then search” method, therefore, files can be kept in their compressed form, saving memory space. When compression gain is important, these algorithms are better than cgrep [Ferragina, P., Tommasi, A., & Manzini, G. (2004). C Library to search over compressed texts, http://roquefort.di.unipi.it/~ferrax/CompressedSearch], which is only slightly faster than ours. 相似文献
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三维引擎中人体动画的研究 总被引：1，自引：0，他引：1
针对项目中对三维引擎的要求对骨骼动画进行了研究。提出了一种实现动画共享的方法,通过运用顶点索引法,大大降低了运算量。结果证明,所用的方法有良好的准确性和较好的实时性。 相似文献
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Barbara S. McClanahan Kenneth D. Ward Chris Vukadinovich Robert C. Klesges Linda Chitwood Stephen J. Kinzey 《Journal of sports sciences》2013,31(6):463-469
There is evidence from previous cross-sectional studies that high volumes of certain sports, including running, swimming and cycling, may have a negative impact on bone mineral density. The aim of the present study was to evaluate prospectively the effects of high athletic training in individuals who engage in high volumes of all three of these activities (triathletes). Bone mineral density for the total body, arms and legs was determined by dual-energy X-ray absorptiometry in 21 competitive triathletes (9 men, 12 women) at the beginning of the training season and 24 weeks later. Age, body mass index, calcium intake and training volume were also recorded to examine potential mediators of bone mineral density change. Men had greater bone mineral density at all sites than women. No significant changes were observed over the 24 weeks for either total body or leg bone mineral density. Bone mineral density in both arms increased by approximately 2% in men ( P ? 0.03), but no change was observed for women. Change in bone mineral density at all sites was unrelated to age, body mass index, calcium intake and training volume. The results suggest that adverse changes in bone mineral density do not occur over the course of 6 months of training in competitive triathletes. 相似文献