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61.
Zhong C Zhuo Y Xia J Hu S Li C Jiang Z Wang S 《Computer methods and programs in biomedicine》2011,101(3):282-296
The reinforced urn processes (RUPs) approach can estimate the target dose on the basis of the prior distribution function precisely and conveniently without the requirements about the explicit-estimated dose-response curve and the posterior complicated inference. The application of the RUPs approach was not discussed from the perspective of phase I clinical trial in the previous studies which just focused on the theory and methodology. And the modification of the traditional RUPs design should be considered for the purposes of ethnics and efficiency. A SAS macro was designed to explore the appropriate parameter settings according to the simulation outcomes in different situations and apply the RUPs approach for two state processes in phase I clinical trail with the modified RUPs design. The posterior estimation can be obtained precisely and efficiently with application of SAS program following the appropriate workflow and determination rule which were described in the example. 相似文献
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PI You-guo LIANG Tian-cai YUE Rong 《通讯和计算机》2008,5(5):28-31
A method of spam detection, based on cognitive pattern recognition, had been proposed. The connection between Email category and cognition of Email user interest within life and work, had been analyzed. Under the guidance of cognitive pattern recognition theory, the mechanism of spam detection, based on intelligent cognition of Email user interest within life and work, had been discussed. Then the spam detection algorithm and its concrete implementation was given. Experimental results demonstrate that the spare detection algorithm has a good learning ability, scalability, and a good ability to achieve high recognition accuracyn 相似文献
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针对视频交通图像的特点,提出了一种将灰度判断与边缘检测相结合来检测交通参数的方法;综合了灰度检测和边缘检测的优点,采用帧平均法来处理视频流,可以减小由于摄像头抖动或背景微小变化而产生的误差;分析了小波变换的特点,应用小波变换对交通图像进行车辆边缘检测,对不同尺度小波变换后的水平方向、垂直方向和对角线方向的高频信息,用互能量交叉的方法进行噪声抑制,突出主要边缘,最后,在车辆边缘识别基础上获得车流量、车速等相关交通参数;实验结果表明,此方法简单、有效,获得了较满意的检测结果。 相似文献
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针对一种新型双级贯流式水轮机,推导了一级导叶、一级转轮、二级导叶和二级转轮的参数设计公式。利用数值模拟商业软件Fluent分析了水轮机在设计工况下的数值性能。数值计算时控制方程采用雷诺时均N-S离散方程,湍流模型选择标准k-ε模型,得到了水轮机的流线图、导叶和转轮叶片的压力面和吸力面的压力分布图,以及中心对称面x=0.083 5的速度矢量图,数值计算结果证明了水轮机设计的正确性。 相似文献
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Infections due to Lancefield group F and related Streptococci (S. milleri, S. anginosus) 总被引:1,自引:0,他引:1
DM Shlaes PI Lerner E Wolinsky KV Gopalakrishna 《Canadian Metallurgical Quarterly》1981,60(3):197-207
We can no longer accept classification of streptococci solely on the basis of hemolytic reactions or Lancefield agglutinations. While the "viridans" streptococci cannot be serologically differentiated, physiological separation of the species offers a satisfactory method of classifying human isolates. We review the microbiology of Lancefield group F and related streptococci (S. milleri, S. anginosus), emphasizing microbial ecology and current taxonomic considerations. A series of 28 patients infected with these organisms is presented. There was a striking male predominance in the series (6:1) as well as an obvious association with underlying diseases and/or antecedent trauma. The most remarkable feature of these pathogens is their predilection for abscess formation, confirming their overdue recognition as the most common "viridans" streptococcus recovered from abscesses within internal organs. We observed purulent disease of the nervous and skeletal systems, oral cavity, lung and pleural space, abdomen and subcutaneous tissues. Microbial synergy (i.e. polymicrobic infection) was not a requisite for abscess formation. Four of the five deaths in this series occurred in patients 60 years of age of older. Some degree of variability in antimicrobial susceptibility was noted, so speciation alone may not always provide sufficient information on which to base a therapeutic decision. 相似文献
70.
Vinyl triethoxysilane grafted high density polyethylene (HDPE-g-YDH151)/Bentonite (BT) composites were prepared via melt compounding and compared with HDPE/BT composites. FTIR proved that HDPE-g-YDH151 is chemically bonded to BT sheets. XRD, SEM and TEM results indicated that the introduction of YDH151 promoted the dispersion and intercalation of BT into HDPE. Consequently, HDPE-g-YDH151/BT composites show satisfied mechanical properties, e.g., the composite with 2phr BT has an elongation at break 29% higher and Young’s modulus 32% higher than that of HDPE-g-YDH151.Comparatively, BT aggregated in HDPE/BT composites and all the mechanical properties decreased. Because of high interfacial adhesion between HDPE-g-YDH151 matrix and exfoliated BT, which reduces the mobility of crystallizable PE chain segments, and subsequently reduces the crystallization ability. In comparison, the addition of BT to HDPE did not affect the crystallization behavior of the later. 相似文献