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41.
HE Yiping~ 《四川大学学报(工程科学版)》2005,(Z1)
Stream blockage by the debris flow from tributary valleys is a common phenomenon in mountainous area,which takes place when large quantities of sediment transported by debris flow reaches a river channel causing its complete or partial blockage.The dam formed by debris flow may causes upstream and downstream flooding,and presents great threat to people and property.Because of the catastrophic influence on people and property,debris-flow dam has attracted many attentions from the researchers and local administration.But,lit- tle attention has been given to the quantitative interrelationships of the potential influential factors.In this pa- per,the interrelationships of important influential factors caused the stream blockage by debris flow were ana- lyzed through flume experiment,and a model to predict the blockage was presented. 相似文献
42.
通过制造4台我国特大型非标冶炼回转炉的实践,以详实的实例,总结性地介绍了在特大型非标设备的制造中,怎样运用技术确定“停工检测点”、“质量见证点”,完成设备制造的成功经验。 相似文献
43.
中国近海海域环境放射性水平调查 总被引:6,自引:0,他引:6
总结中国在过去40年中对近海海域环境放射性的调查结果,介绍了中国近海海域中天然和人工放射性核素的水平,海洋生物对放射性核素的吸收与累积,以及海洋沉积物对放射性核素的吸附。 相似文献
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J. Pohlus 《Progress in Nuclear Energy》2003,43(1-4):27-34
The nuclear reactor core design and the nuclear fuel management have been changed remarkable during the last few years. This development was initiated by increasing costs for the fuel recycling and nuclear waste storage. The fuel material, the fuel pellet fabrication, the fuel assembly structure and the core composition have been varied to get an effective fuel exploitation. Based on advanced core process conditions the reactor power and the fuel burn-up have been increased at German plants in recent years. Improved dynamic process monitoring procedures are required to get more information about the varied core process behaviour during the reactor operation. Since several years ISTec has been performed investigations to the process monitoring based on process signal measurements in German nuclear power plants. Using the standard instrumentation of the plants process signals have been measured and analysed by means of the digital data acquisition system SIGMA. The measured time signals are influenced by core process transients, global and local process fluctuations and by signal line transfer functions. Advanced time series analysis methods have been applied to separate different process effects in the multiple signal matrix. The separation of different process influences can improve significantly the information about the process condition in the reactor core. 相似文献
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Matthias M. Müller 《Empirical Software Engineering》2004,9(4):335-351
From the first presentation of extreme programming on, pair programming has attracted a wide range of programmers to work together in front of one display. The proposed advantages of pair programming are a faster development cycle and code with higher quality. However, the nearly doubled personnel cost when compared to single developers seems to outweigh these advantages. Instead of showing the superiority of pair programming, we seek an alternative. Can a single developer be assisted by an already known technique with which he produces the quality of pairs with only a fraction of the cost? The answer with some restrictions is: yes, he can. Reviews are a reasonable candidate with respect to code quality and cost. 相似文献
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