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This paper explores the quantitative relationship between knowledge sharing and performance, with contextual factors in consideration. First, we argue that both knowledge sharing and its contextual factors should be associated with performance. Then, we analyze the multi-dimensional characteristics of knowledge sharing and propose six measures for it. Next, we model the relationship between knowledge sharing and performance, integrating various contingent factors with the model framework, some of which have significant influences on the relationship between knowledge sharing and performance. After that, we propose four alternative models and corresponding propositions for knowledge sharing-contingent variables relationship, and present a quantitative formulation of the relationship between knowledge sharing and performance. Finally, we conduct a survey of 249 organizations in Xi’an, China, and show the empirical results. Our propositions about the knowledge sharing-performance relationship and contingent factors are supported by the survey. The empirical results suggest that managers have to pay attention to some contingent factors while they commit to knowledge sharing. This study adds to the understanding of the effects of knowledge sharing on performance, and gives implications to the practice of knowledge sharing.  相似文献   
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In order to know the maximum mining ground deformation of arbitrary surface point, directions of the maximum surface tilt, curvature,horizontal displacement and horizontal deformation caused by multi-working faces were deduced based on probability integral method. The distribution forms of surface deformations in all direction φ∈[0, 2π] were obtained and also equations of maximum deformations were given based on calculation of mining ground deformation in direction φ. A mining subsidence analysis system was developed with VB6.0. The system implements the probability integral mining subsidence prediction with direct integration method, and it can avoid errors of arbitrary shaped working face subdivision of traditional method, and accuracy of mining subsidence prediction can be improved with the direct integral method. The system implements the contour chart and profile chart and also data analysis automation by manipulation of the SURFER kernel function and it complements the defect of existing subsidence prediction software. Calculation of maximum deformations caused by multi-working faces mining in a coal mine of Xuzhou, China was shown as application example. Engineering application indicates that maximum deformation of mining ground surface can be calculated and analyzed by the system. The research provides a theoretical basis and calculation tool for mining subsidence prediction and analysis.  相似文献   
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采用热活化过硫酸钠技术处理亚甲基蓝模拟染料废水,考察了反应温度、过硫酸钠用量、溶液pH以及溶液离子强度对亚甲基蓝模拟染料废水脱色效果的影响.研究结果表明:升高反应温度和增大过硫酸钠的质量浓度会提高亚甲基蓝的去除率,80℃,n(过硫酸钠)∶n(亚甲基蓝)=50∶1时,反应3 h,亚甲基蓝去除率可达90%以上;在pH=2~10时,溶液pH越低,亚甲基蓝的去除效率越高,碱性条件会明显地抑制亚甲基蓝的去除;溶液离子强度影响反应体系的反应速率,离子强度增大(0.11~0.25 mol/L)会降低过硫酸钠氧化亚甲基蓝的反应速率.  相似文献   
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陕北地区黍米黄酒与江浙地区传统黄酒在品质上形成差异的主要影响因素有酿酒原辅料特性、地域环境、生产工艺、微生物种类和数量等。风味成分和氨基酸分析结果表明,2种黍米黄酒中氨基酸总量、各种氨基酸含量高于稻米黄酒;两者的风味物质存在明显差异,苯乙醇和苯乙酸乙酯是体现黍米黄酒酒体风格的重要风味物质。  相似文献   
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《Fire Safety Journal》2001,36(5):477-489
A two-dimensional model to simulate the flow and temperature fields in underground coal fires has been studied. The model is based on the theory of natural convection in porous media. A numerical solution procedure is used. Its predictions are compared with the limited field temperature data available. It is found from the model predictions that fractures or higher permeability are necessary to enhance natural convection. The air penetrates in the area behind the fire where many fractures of higher permeability occur due to subsidence. Air flows out from the hot area or cold area in front of the fire. In a shallow depth fire convection plays an important role, whereas in a deep fire convection velocities are smaller. Moreover, secondary combustion of volatiles produced from coal seam in the fracture or crack can markedly increase the convection.  相似文献   
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《Materials & Design》1987,8(2):89-92
The author first describes some of the basic ferrous PM materials in production and then outlines a novel computer-based program which has been developed specifically to aid the process of their selection.  相似文献   
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