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181.
阐述了TBM(隧道掘进机)半个世纪以来的发展及其在国内外隧道建设中的应用,指出优先采用TBM掘进技术进行隧道开挖已成为未来隧道建设总的发展趋势;并在分析大量国内外工程实例的基础上,结合TBM施工中的经验及教训,对TBM掘进过程中存在的诸如断层破碎带、挤压地层、地下水、岩溶等相关工程地质问题进行了探讨,并提出了相应的处理措施。  相似文献   
182.
The central theme of this paper is the issue of the governance of cooperation within the Chilean wine industry. The effects of the internationalization of this industry for the importance and the quality of governance of intra-cluster cooperation involving firms and other actors are analysed. Two questions stand central. First, what has been the relative importance of external and internal factors in improving the export performance of the Chilean wine industry over the past 20 years? Second, to what extent have collective actions and investments played a part in this growth, and what has been the quality of the various governance regimes dealing with the associated collective action problems? Empirical evidence suggests that world-market developments and upgrading efforts by individual wineries largely explain the good export performance of the Chilean wine industry until the year 2000. The evidence also shows that the industry’s success in world markets is stimulating cooperation between firms and other actors in areas where the industry needs to improve: marketing and promotion, internationalization, innovation and training. The enhanced cooperation has not only stimulated cluster development, but has also turned the quality of cluster governance into a central variable for future export growth. Nevertheless, several collective action problems await resolution before essential intra-cluster cooperation can develop. Overall, the evidence suggests that, in the case of the Chilean wine industry, industrial and cluster development do not automatically follow enhanced integration in world markets, but depend on the strategic skills of actors within the industry, in particular their ability to identify, prioritize, and realize collective investments while effectively managing the associated collective action problems. Internationalization stimulates firms to consider such investments, however, and provides them with an incentive to upgrade strategic skills at the local level as new opportunities arise and the pressure is there to exploit them in world markets.  相似文献   
183.
滨海城市环境工程地质问题发育特点分析   总被引:1,自引:0,他引:1  
本文分析了我国滨海城市环境工程地质问题的主要类型,研究了环境工程地质问题的发育特点。  相似文献   
184.
受控自回归滑动平均模型是用来描述随机现象中输入与输出关系的一类线性动态模型。本文以大柳塔井田双沟泉域为例,应用该模型分别对双沟泉域在天然条件和矿井疏水条件下的泉流量进行预测,并据此评价矿井疏水对泉流量的影响。  相似文献   
185.
Numerical computations concerning geochemical processes in porous media require a knowledge of the values of the macroscopic parameters. In the context of the interpretation of leaching tests one such parameter is the apparent macroscopic diffusivity. In this paper, a mathematical model for dissolution in the presence of diffusion is considered. It is shown that the constant diffusion coefficient can be identifiable when the time integral of the flux is known. Moreover, a practical algorithm for computing the diffusion coefficient is proposed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
186.
我国矿泉水开发过程中一些问题的思考   总被引:2,自引:0,他引:2  
针对我国矿泉水生产过程中出现的问题,提出矿泉水生产的工艺流程设计必须考虑自身水质特点;输水采用卫生级不锈钢管、接管配件及卫生级传输泵;洁净车间的洁净度必须达到药品(针剂)生产净化级次的要求。建议矿泉水业加强行业管理,重视质量,以市场为导向开发稀有的特殊矿泉水,包装和产品品种向系列化方向发展。  相似文献   
187.
河南省地处中原,交通发达,人口稠密,人类工程经济活动强烈。全省地貌类型齐全,岩土体类型复杂。在水库建设、矿产开发和铁路公路建设中出现了一系列环境工程地质问题,岩土体类型不同,其工程地质特性各异,产生的环境工程地质问题亦不尽相同。分析岩土体类型及其工程地质特征,是治理环境工程地质问题、防治人为灾害的基础。本文介绍了河南省岩土体类型及其主要工程地质特征。对水库区、采矿区及交通建设中出现的环境工程地质问题进行了详细论述,为治理环境工程地质问题、防治人为灾害提供了地学依据。  相似文献   
188.
We investigate the use of general, non- l 2 measures of data misfit and model structure in the solution of the non-linear inverse problem. Of particular interest are robust measures of data misfit, and measures of model structure which enable piecewise-constant models to be constructed. General measures can be incorporated into traditional linearized, iterative solutions to the non-linear problem through the use of an iteratively reweighted least-squares (IRLS) algorithm. We show how such an algorithm can be used to solve the linear inverse problem when general measures of misfit and structure are considered. The magnetic stripe example of Parker (1994 ) is used as an illustration. This example also emphasizes the benefits of using a robust measure of misfit when outliers are present in the data. We then show how the IRLS algorithm can be used within a linearized, iterative solution to the non-linear problem. The relevant procedure contains two iterative loops which can be combined in a number of ways. We present two possibilities. The first involves a line search to determine the most appropriate value of the trade-off parameter and the complete solution, via the IRLS algorithm, of the linearized inverse problem for each value of the trade-off parameter. In the second approach, a schedule of prescribed values for the trade-off parameter is used and the iterations required by the IRLS algorithm are combined with those for the linearized, iterative inversion procedure. These two variations are then applied to the 1-D inversion of both synthetic and field time-domain electromagnetic data.  相似文献   
189.
珲春经济开发区环境地质问题研究   总被引:1,自引:0,他引:1  
珲在经济开发区,在大力发展经济的同时,地质环境开始恶化,作者在系统调查的基础上,将全区划分为两个环境地质和五个环境地质亚区,详尽地记述了全区主要环境地质问题的现状,成因和发展趋势,同时有针对性地提出了一系列的防治对策和可行的建议。  相似文献   
190.
本文对环境工程地质这的理论问题,重大环境工程地质问题及典型实例,环境保护,减灾对策和灾害损失评价等方面进行了系统的分析,总结,最后,对环境工程地质学的发展提出了4点建议。  相似文献   
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