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排序方式: 共有506条查询结果,搜索用时 125 毫秒
1.
以左云长春兴煤业公司301综放工作面扇形收尾施工工艺为背景,介绍了在工作面受地质构造或者井田边界影响,工作面两顺槽与盘区大巷斜交布置时,为了多回收煤炭资源,提高经济效益,采取大角度扇形收尾的施工工艺,为厚煤层放顶煤大角度扇形收尾提供了借鉴和理论依据。 相似文献
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本文介绍预应力混凝土技术在某工程地下室顶板的设计思路以及预应力的应用优势,为相近工程提供一些参考。 相似文献
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上海环球金融中心结构设计简析 总被引:1,自引:0,他引:1
上海环球金融中心是一座多功能、先进智能型的摩天大厦,建成后总高度达492米,为世界第一高楼。设计建造这一超级摩天大厦是一项复杂的系统工程,尤其在结构设计方面,如何选用最有效的结构体系,如何建立完善的计算模型,以及如何进行全面的计算分析都是结构设计的关键问题。本对上海环球金融中心的结构设计及施工方案进行了较全面的介绍。 相似文献
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混凝土厚板广泛应用于石化装置的设备基础及混凝土构筑物中。由于板受力特殊,内力分布复杂,尚无精确的内力分析方法。重点介绍如何使用等代框架法、有限元法设计板柱结构,通过SAFE、SLABCAD等有限元分析软件对低温储罐底基础顶板进行内力分析比较,并结合有限元分析结果,结合实际经验,给出基础顶板合理配筋范围。 相似文献
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This study focuses on the relationship and identity changes within and between a project team and its organization following top management intervention in the context of a large international construction project. The study follows the project-as-practice orientation, examining the actions and behaviors of the project team through participant ethnography in the “praxis” of the project site over its entire duration. The longitudinal case allows the examination of the way the transition process established a new governance culture undermining the initial trust-based one and changed it from a virtual absence of mechanisms toward far more potent mechanisms of control, monitoring, and punishment. Simultaneously, the initial stewardship relationships and collectivist identity of the project team shifted toward agency relationships and individualistic identity. The triggers for the transformation process were identified as CEO succession, project failure, top management intervention driven changes in governance mechanisms, and perception of organizational betrayal of the project team. 相似文献
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J. Kurobe 《Science and Technology of Advanced Materials》2013,14(4):251-259
The motions of top and bottom dross in a continuous hot dip plating bath were investigated using a transparent cold model vessel with a reduced scale of one-tenth. The flow field in the model bath was classified into three regions as usual; the entry region, the exit region, and the region enclosed with a belt. This belt was used as a model for a strip. Polystyrene particles were used as models both for the top and bottom dross while NaCl aqueous solutions of different densities were used as models for plating melts. The motions of model particles were observed by eye inspection and by using a high-speed video camera. Local particle frequency and particle holdup were measured with a newly developed sensor. Typical streak lines for the top and bottom dross particles were similar to main stream lines in the bath. Both the top and bottom dross particles were rich in the region enclosed with the belt. A lot of top dross particles floated on the bath surface near the side walls, while many bottom dross particles stayed on the bottom wall in the entry region. 相似文献
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A double-gate (DG) fin field effect transistor (FinFET) is discussed as new label-free ion and biological sensor. Simulations as function of channel doping, geometrical dimensions, operation point and materials investigated the device response to an external potential difference which provides a body threshold voltage modulation. The simulation results presented in this work clearly state the key features for an ultrasensitive FET based sensor: an enhancement low doped and partially gated transistor operating in weak-moderate inversion regime. The optimized sensitivity, obtained when the width of the fin is equal to the gate height (wNW ∼ hg), reaches a value of 85% for an extraction current, Id, of 0.1 μA. These results pave the way for the fabrication process of an innovative CMOS compatible sensing system. 相似文献
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为帮助电信运营商在与OTT运营商的竞合中赢得主动权,文章通过分析通讯行业发展趋势,结合OSS/BSS领域的最新技术能力,为运营商指明在OSS/BSS层面需要着力把控的三个重要发展方向:1)提高快速、动态响应用户需求和新商业模式的能力,2)具备与用户、合作方、网络实时交互的能力,3)简单、灵活的OSS/BSS架构体系。 相似文献