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一种新的L-集表现定理 总被引:1,自引:1,他引:0
在隶属度值格仅为完备格的条件下,研究了L-集轮和L-开集轮的特征性质,并以2种集轮为工具给出基于L-集轮和L-开集轮的L-集表现定理.由于隶属度值格仅为完备格,得到的L-集表现定理更有一般意义. 相似文献
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Tunnel blasting techniques in difficult ground conditions 总被引:1,自引:0,他引:1
Summary The quality of tunnelling can be improved by proper blast design which takes into account the rock mass conditions. The effects of different rock mass properties on tunnel blast performance need to be assessed. The strength of the formation and joint orientation critically affected fragmentation and overbreak in a model study of blasting. Similar effects were noted in situ when the performance of a blast pattern in different rock mass conditions in the Tandsi inclines (Bihar, India) were analysed. Accordingly, the on-going blast pattern was modified for the poor ground conditions prevailing in the rest of the inclines. Improved fragmentation and smooth profile were obtained as a result; the rate of drivage improved considerably and the cost of excavation was reduced. Based on the observations in the model studies and the investigations at Tandsi, some guidelines for optimum blast design in difficult ground conditions are suggested. 相似文献
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国内外的台网中总是一些台站,其极性读取似乎是由大量台站P波初动的整体分布确定的震源机制相矛盾,这些矛盾通常被作为坏读(bad reading)处理,造成台站的极性问题的复杂原因究竟是什么,利用NEIC的核爆资料,文中给出两种可能推测:台站仪器本身的不可和地震本身的复杂性。 相似文献
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Summary An overview of economics and design consideration for explosive overburden casting is given and the criteria for the successful application of this technique are discussed. These criteria are: blast design, economic considerations and environmental considerations. Explosive overburden casting may effect considerable cost savings if the market for increased production is available. However, if a fixed sales constraint exists the economic benefits of explosive overburden casting may be marginal and an extensive economic analysis is warranted. 相似文献
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焊齿破岩滚刀钻头适应多种地层钻进。本文主要介绍了焊齿破岩滚刀钻头的钻进工作原理,在桩基施工中的钻进技术参数,滚刀刀齿的修复及应用效果。 相似文献
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The effect of the long‐period filter cut‐off, Tc, on elastic spectral displacements is investigated using a strong ground‐motion database from Europe and the Middle East. The relation between the filter and oscillator responses is considered to observe the influence of Tc for both analogue and digital records, and the variations with site classification, magnitude, filter order and viscous damping. Robust statistics are derived using the re‐processed European data to generalize the effects of the long‐period filter cut‐off on maximum oscillator deformation demands as a function of these seismological and structural features. Statistics with a 95% confidence interval are derived to suggest usable period ranges for spectral displacement computations as a function of Tc. The results indicate that the maximum period at which spectral displacements can be confidently calculated depend strongly on the site class, magnitude and filter order. The period range where reliable long‐period information can be extracted from digital accelerograms is twice that of analogue records. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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