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FRP 聚合物 1

中国铁路“走出去” 1

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Self-generation of machining precision and its realization in lapping of super precision solid balls

ZHANG Bopeng

《机械工程前沿（英文）》 2008年第3卷第3期页码 348-353 doi: 10.1007/s11465-008-0065-7

摘要： This paper presents the principle of self-generation of machining precision by explaining its basic concept and five necessary conditions for forming a system with self-organization capability. A self-generation system is a kind of system with self-organization capability. The self-generation of machining precision for solid balls with super precision is emphatically explained. From the viewpoint of self-organization, there are three types of systems including system 1 with the self-regulation capability, 2 with the self-determination capability of goals, and 3 with the self-organization capability. Although they are all closed loop control systems, they have different constructions and functions. Necessary conditions for achieving self-generation of machining precision are given. Establishment of the system for machining solid balls with super precision is discussed. Self-generation of machining precision for solid balls with super precision on the basis of the capability of self-removal of errors is presented. Self-generation includes the ability of self-removal of errors for solid balls, convergence of self-removal of errors, self-generation of precision, and self-generating system for the given.

关键词： self-generation necessary self-regulation capability viewpoint Necessary

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To restrict indication for stenting of the inferior vena cava and liver transplantation in patients with Budd-Chiari syndrome

WANG Zhonggao

《医学前沿（英文）》 2007年第1卷第2期页码 130-135 doi: 10.1007/s11684-007-0025-3

摘要： The Budd-Chiari syndrome (BCS) used to be a very rare disorder and lacked a means of relieving. However, various shuntings and radical procedures have emerged in the last three decades with quite encouraging outcomes. Recent minimally invasive therapies, such as stenting of the inferior vena cava (IVC), are simple and easy to handle. However, it has been realized that the IVC stent may compromise the hepatic veins and cause catastrophic consequences, thus the indication for IVC stenting should be reevaluated and especially not to be overused. Instead, it should be applied by percutaneous transangiography (PTA) only, which may be repeated when necessary. The BCS in China predominantly belongs to the IVC type rather than the intrahepatic type in Western; the outcome from its conventional therapy, at least for the moment, is better than that of liver transplantation. It is thus suggested that, before liver transplantation is decided, the conventional means for managing BCS be considered. The final suggestion is to restrict the indication both for stenting of the IVC and liver transplantation. In this paper, ten examples are given with figures.

关键词： Budd-Chiari syndrome conventional intrahepatic percutaneous transangiography necessary

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Analysis of the dynamic hysteresis characteristic of finger seal

LEI Yanni, CHEN Guoding

《机械工程前沿（英文）》 2007年第2卷第1期页码 32-36 doi: 10.1007/s11465-007-0005-y

摘要： The research about hysteresis characteristic of finger seal (FS), which was carried out based on the model with static loads, could not reflect the dynamics behavior of FS system when the rotor runs at high speed. To solve this problem, the relations between the dynamics parameters, structure parameters as well as working parameters in the system were given out through the analysis of finite element analysis result. A mass spring damper dynamics model of FS system was proposed and the hysteresis characteristic of the FS system was analyzed. This work shows that the dynamics characteristic analysis of the FS is necessary and the dynamics model proposed in this paper is valid. This dynamics model is the basis for the optimization design of FS system.

关键词： FS necessary hysteresis characteristic optimization spring

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Error analysis of the parameters for non-coaxial grazing X-ray microscope

ZHAO Lingling, HU Jiasheng, LI Xiang

《机械工程前沿（英文）》 2007年第2卷第3期页码 323-329 doi: 10.1007/s11465-007-0057-z

摘要： A non-coaxial grazing X-ray microscope, consisting of four spherical mirrors, is designed for diagnosis of inertial confinement fusion (ICF). The aberrations and imaging quality of the microscope are analyzed. To acquire excellent imaging quality, suitable tolerances for manufacturing and assembling the microscope are necessary. This paper researches the changes of Gauss parameters and aberrations due to component and subsystem parameters (such as the radius of the mirror, angle between mirrors, grazing angle, object distance, etc.). Here, spot diagrams and modulation transfer function (MTF) are first adopted to quantitatively evaluate the imaging quality of the microscope. Suitable manufacturing tolerances of components and assembly tolerances of the system are established on the basis of the discussion and analysis. A set of non-coaxial grazing X-ray microscopes is manufactured based on the tolerances. In site tests of ICF, the images with high resolution are obtained by the microscope.

关键词： non-coaxial spherical manufacturing necessary diagnosis

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A case of big substernal goiter resection

SONG Jiangping, LIAO Hongying, YU Chao, ZHANG Jian, Li Yun, GU Lijia

《医学前沿（英文）》 2008年第2卷第4期页码 410-413 doi: 10.1007/s11684-008-0079-x

摘要： Substernal goiter is considered to be a diagnostic differential for all anterosuperior mediastinal masses. For a substernal goiter, surgical removal is suggested when it is large in size, with a possibility for malignancy or has local compression of adjacent structures. This can be performed through the neck or by the addition of a partial or complete sternotomy if necessary. A 58-year-old Chinese man from Guangdong Province had had dry cough for a year. A subsequent CT scan in our hospital suggested “ectopic intrathoracic thyroid”. Fine needle percutaneous mass biopsy also suggested “ectopic intrathoracic thyroid”. We performed a standard median sternotomy to remove the mass. It measured 13 cm × 8 cm × 6 cm in size, and weighed 2.8 kg. The pathological diagnosis confirmed a benign thyroid adenoma. The patient had no hoarseness, dyspnea or hypocalcemia and was quickly extubated in the operating room. Recently, we encountered a big substernal goiter and had performed successful resection, which is reported here for reference.

关键词： percutaneous diagnostic differential necessary compression intrathoracic

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混凝土结构性干预所必需的材料力学性能 Article

Tamon Ueda

《工程（英文）》 2019年第5卷第6期页码 1131-1138 doi: 10.1016/j.eng.2019.02.012

摘要：

结构性干预包括修复和（或）改善结构性能。除了混凝土和钢材这两种典型的混凝土结构材料外，各种纤维增强复合材料（FRP），混合纤维、聚合物和黏合剂的黏结材料也常被用于结构性干预。为了预测结构性能，有必要开发一种不仅适用于钢材，而且适用于其他材料的通用方法。这种通用模型可以提供有关改善结构性能所需的力学性能的信息。外部黏结是一种典型的结构干预方案，在新结构中没有得到应用。为了在基体混凝土和外部黏结材料的接合点上获得更好的黏结强度，我们有必要阐明材料的性能和结构细节。本文介绍基体混凝土的力学性能和相关干预材料用于以下目的：①获得更高的抗剪强度和减少构件在结构性干预后的极限变形；②使外部黏结获得更高的黏结强度。本文得出的结论是，在有结构干预的结构中，为了提高结构的力学性能，干预材料的一些力学性能和结构细节是新的，且不同于没有干预的结构。例如，在无结构性干预的结构中，高强度和高刚度是材料的重要性能，而高断裂应力和低刚度是结构干预材料的重要性能。

关键词：结构性干预高断裂应力无屈服低刚度粗糙度 FRP 聚合物