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莎士比亚全集

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用蒙特卡罗方法求取广义线性混合模型之最大似然估计:应用于求取乳癌死亡率之小区域估计（英文）

作者： w.·莎士比亚 w.·Shakespeare

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应用概率统计 2006年第1期22卷 69-80页

作者：陈永成 Stephen w.Raudenbush 密西根州立大学教育学院测量及数量方法美国48824 密西根大学教育学院及社会研究协会美国***

本文使用蒙特卡罗方法,求得广义线性混合模型之最大似然估计,并提供用来评估统计参数之收敛和精确度之实用方法．仿真研究显示无偏之固定效应参数估计,而方差分量估计之误差则相近于前人结果．应用举例为使用泊松分布求取乳癌死亡率之... 详细信息

本文使用蒙特卡罗方法,求得广义线性混合模型之最大似然估计,并提供用来评估统计参数之收敛和精确度之实用方法．仿真研究显示无偏之固定效应参数估计,而方差分量估计之误差则相近于前人结果．应用举例为使用泊松分布求取乳癌死亡率之小区域估计．

关键词：广义线性混合模型最大似然估计泊松分布蒙特卡罗 EM算法

A model of deformation of thin-wall surface parts during milling machining process

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Journal of Central South University 2018年第5期25卷 1107-1115页

作者：王凌云黄红辉 Rae w.wEST 李厚佳杜继涛 Department of Manufacturing Engineering and Technology Shanghai University of Engineering Science College of Engineering University of Nevada-Las Vegas

A three-dimensional finite element model was established for the milling of thin-walled parts. The physical model of the milling of the part was established using the AdvantEdge FEM software as the platform. The aluminum alloy impeller was designated as the object to be processed and the boundary conditions which met the actual machining were set. Through the solution, the physical quantities such as the three-way cutting force, the tool temperature, and the tool stress were obtained, and the calculation of the elastic deformation of the thin-walled blade of the free-form surface at the contact points between the tool and the workpiece was realized. The elastic deformation law of the thin-walled blade was then predicted. The results show that the maximum deviation between the predicted value and the actual measured machining value of the elastic deformation was 26.055 μm; the minimum deviation was 2.011 μm, with the average deviation being 10.154 μm. This shows that the prediction is in close agreement with the actual result.

关键词： thin-walled surface parts milling force elastic deformation finite element model

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雷击风机叶片的跃变击距特性与定量表征

电工技术学报 2017年第15期32卷 216-224页

作者：任瀚文郭子炘马宇飞李庆民 Siew w H 新能源电力系统国家重点实验室(华北电力大学) 北京102206 The University of Strathclyde

风机叶片对雷电的接闪是风机防雷研究中的关键内容,合理分析接闪时的击距特性意义重大。基于雷击过程的物理机制,将雷击发生时上、下行先导头部间的距离定义为跃变击距,并分析了多上行先导竞争对风机接闪和跃变击距的影响。基于先导起... 详细信息

风机叶片对雷电的接闪是风机防雷研究中的关键内容,合理分析接闪时的击距特性意义重大。基于雷击过程的物理机制,将雷击发生时上、下行先导头部间的距离定义为跃变击距,并分析了多上行先导竞争对风机接闪和跃变击距的影响。基于先导起始和发展理论,根据下行先导的等效模型和稳定上行先导的判定方法建立了风机叶片接闪模型,利用该模型得到了随雷电流幅值变化的跃变击距公式,指出侧面距离等参数对跃变击距没有影响,实验和观测结果证明了模型的正确性。最后利用接闪模型提出了考虑稳定上行先导对周围电场畸变作用的对地击距公式,与其他学者计算的结果进行对比指出,现有对地击距公式或不适用于风机背景的防雷计算。

关键词：风机叶片跃变击距多先导竞争对地击距接闪模型

Deposition and Magnetic Properties of Fe_3O_4/Fe/Fe_3O_4 Tri-layer Films

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Journal of Materials Science & Technology 2000年第2期16卷 191-194页

作者： T.S.Chin and w.C.Yang (Department of Materials Science and Engineering, Tsing Hua University 101, Section 2, Kuang-Fu Rd., Hsinchu, 30043, Taiwan-China) Department of Materials Science and Engineering Tsing Hua University 101 Kuang-Fu Rd. Hsinchu 30043 Taiwan

The Fe_3O_4/Fe/Fe_3O_4 (MIM) tri-layer films (200 nm/12-93 nm/200 um) were prepared on Si(100) by DC-magnetron reactive-sputtering followed by air- or vacuum-annealing at 280-400℃ for 1.5 h, respectively. Magnetic properties and phases under different sandwich and annealing conditions were studied. In MIM structure, the incorporation of the interlayer iron does increase the magnetization measured under 8 kOe (M_8K), but reduce coercivity (H_c). The H_c of asdeposited films decreases from 354 Oe to 74 Oe; while M_8K increases from 254 to 392 emu/cc. By annealing in air, the whole MIM tri-layer film becomes γ-F_e2O_3, H_c is about 550 O_e and M_8K is around 250 emu/cc. The coercivity mechanism of as-deposited and annealed MIM trilayer films belongs to domain-wall pinning type. δM plots show that when the interlayer Fe thickness is 12 um, the Fe and Fe_3O_4 layers are decoupled in the as-deposited and annealed states; while it is coupled in the as deposited state when the Fe thickness increases to 23 um. Vacuum annealing of the MIM films leads to increase in both coercivity and magnetization, and to enhance the exchange coupling between layers.

关键词： Fe Deposition and Magnetic Properties of Fe3O4/Fe/Fe3O4 Tri-layer Films

Temperature-controlled mode selection of Er-doped random fiber laser with disordered Bragg gratings

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Photonics Research 2016年第3期4卷 102-105页

作者： w.L.Zhang Y.B.Song X.P.Zeng R.Ma Z.J.Yang Y.J.Rao Key Laboratory of Optical Fiber Sensing & Communications (Education Ministry of China) University of Electronic Science & Technology of China

In this paper, we proposed a way to realize an Er-doped random fiber laser(RFL) with a disordered fiber Bragg grating(FBG) array, as well as to control the lasing mode of the RFL by heating specific locations of the disordered FBG array. The disordered FBG array performs as both the gain medium and random distributed reflectors, which together with a tunable point reflector form the RFL. Coherent multi-mode random lasing is obtained with a threshold of between 7.5 and 10 mw and a power efficiency between 23% and 27% when the reflectivity of the point reflector changes from 4% to 50%. To control the lasing mode of random emission, a specific point of the disordered FBG array is heated so as to shift the wavelength of the FBG(s) at this point away from the other ***, different resonance cavities are formed, and the lasing mode can be controlled by changing the location of the heating point.

关键词： mode Temperature-controlled mode selection of Er-doped random fiber laser with disordered Bragg gratings

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莎士比亚全集

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Parvovirus B19 induced hepatic failure in an adult requiring liver transplantation

作者： w.·莎士比亚 w.·Shakespeare

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world Journal of Gastroenterology 2009年第32期15卷 4067-4069页

作者： Darin S Krygier Urs P Steinbrecher Martin Petric Siegfried R Erb Stephen w Chung Charles H Scudamore Andrzej K Buczkowski Eric M Yoshida Division of Gastroenterology Department of MedicineVancouver General HospitalVancouverBC V5Z 1M9Canada British Columbia Center for Disease Control VancouverBC V5Z 4R4Canada Department of Surgery Faculty of MedicineVancouver General HospitalVancouverBC V5Z 1M9Canada

Parvovirus B19 induced acute hepatitis and hepatic failure have been previously reported, mainly in children. Very few cases of parvovirus induced hepatic failure have been reported in adults and fewer still have required liver transplantation. we report the case of a 55-year-old immunocompetent woman who developed fulminant hepatic failure after acute infection with Parvovirus B19 who subsequently underwent orthotopic liver transplantation. This is believed to be the first reported case in the literature in which an adult patient with fulminant hepatic failure associated with acute parvovirus B19 infection and without hematologic abnormalities has been identified prior to undergoing liver transplantation. This case suggests that Parvovirus B19 induced liver disease can affect adults, can occur in the absence of hematologic abnormalities and can be severe enough to require liver transplantation.

关键词： Parvovirus B19 Fulminant hepatic failure Orthotopic liver transplant Fulminant hepatitis

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社会学和现代系统论

世界社会科学 1989年第6期 25-30+36页

作者： w.巴克莱 ,鲁品越

我们不打算在给系统概念的下正式定义上兜来兜去。我们的重点将置于用结构布局和动力机制来规定主要系统类型的划分,并放在由此产生的社会分析方法论问题上。我们感兴趣的系统类型可以一般地描述为以直接或间接的因果关系网而相联的各... 详细信息

我们不打算在给系统概念的下正式定义上兜来兜去。我们的重点将置于用结构布局和动力机制来规定主要系统类型的划分,并放在由此产生的社会分析方法论问题上。我们感兴趣的系统类型可以一般地描述为以直接或间接的因果关系网而相联的各元素的复合体,这些元素间的联系方式至少在任何一段时间内是多少稳定的。而各元素可以是较简单稳定的,也可是相对复杂和变动的。它们可以在一两个性质上相异,也可采取许多不同形态。它们间的关系可以是双向的,也可是单向的,可以是线性的,也可是非线性的或间断性的,并且可在因果功效或优

关键词：结构种类实体性概念思维形式外部信息目标状态程序状态现代系统论机械系统文化系统文化体系社会学张力状态信息论适应性系统驱动力广义