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161.
尹翠芝 《常州信息职业技术学院学报》2013,(6):86-88,91
泛珠三角区域经济发展差异很大,利用多元统计中的因子分析法对其进行分析,提取了地区发展的三个因子:工业发展因子、效益发展因子和农业发展因子.利用因子得分对不同具体地区进行排序,解释其原因,分析泛珠三角中各地区的发展差异,并提出相应的进一步合作发展对策. 相似文献
162.
Mechanical Seal Failure Analysis 总被引:1,自引:0,他引:1
This article presents a study on failure analysis of mechanical face seals using reliability tools such as the Weibull and WeiBayes techniques. The Weibull tool is used when a reasonable number of failure data are available, whereas the WeiBayes approach is employed when the failure data are scarce or nonexistent. Results from this study have been used in determining the characteristic life and slope used in assessing warranty cost as well as for selecting the best design from a pool of different designs. Weibull and WeiBayes techniques have been applied to analyzing failures of a wide variety of machines and machines components. This study is an example of the application of the techniques to failure analysis of mechanical face seals. 相似文献
163.
Jian-Hai Zhang Jiang-Da He Jing-Wei Fan 《International Journal of Rock Mechanics and Mining Sciences》2001,38(8):1081-1090
A rigid body–spring element method is used to evaluate the static and dynamic stability of slopes or dam foundations. The versatility of the method applies well to both static and dynamic problems for blocks of arbitrary polyhedral shape with various re-entrant surface features. Examples show that the safety factor obtained in this way agrees well with theoretical solutions. The dynamic safety factor determined with this method varies with time, which differentiate it from the results of the limit equilibrium method or the finite element method. The method also makes it possible to search for the most probable sliding mass. 相似文献
164.
针对新桥硫铁矿矶山东部边坡第四系土层厚,透水性强,新沟距边坡近(仅50m),形成直接补给,临近边坡的专用线位于边坡上方,边坡安全稳定要求高等总是以了帷幕注浆、疏干排水等综合治理措施,取得了显著成效。 相似文献
165.
Artur Palha Loureno Mendes Conceio Juana Fortes Ana Brito-Melo Antnio Sarmento 《Renewable Energy》2010,35(1):62-77
This paper describes the study of the impact of energy absorption by wave farms on the nearshore wave climate and, in special, the influence of the incident wave conditions and the number and position of the wave farms, on the nearshore wave characteristics is studied and discussed. The study was applied to the maritime zone at the West coast off Portugal, namely in front of São Pedro de Moel, where it is foreseen the deployment of offshore wave energy prototypes and farms between the 30 m and 90 m bathymetric lines, with an area of 320 Km2. In this study the REFDIF model was adapted in order to model the energy extraction by wave farms. Three different sinusoidal incident wave conditions were considered. Five different wave farm configurations, varying the position of the wave farm, its number and the width of the navigation channels at each wave farm were analysed. The results for each configuration in terms of the change of the wave characteristics (wave height and wave direction) at the nearshore are presented, compared and discussed for three representative wave conditions. 相似文献
166.
介绍在露天矿边坡的导线测量中,应用PC-E500微机进行观测记录、平差计算及内业成果事理的程序编制。 相似文献
167.
Centrifuge model tests of geotextile-reinforced soil embankments during an earthquake 总被引:6,自引:0,他引:6
The behavior of geotextile-reinforced embankments during an earthquake was investigated using centrifuge model tests, considering a variety of factors such as gradient of slope, water content of soil, geotextile spacing, and input shaking wave. The geotextile-reinforcement mechanism was revealed on the basis of the observations with comparison of the unreinforced embankment. The geotextile significantly decreases the deformation of the embankment and restricts sliding failure that occurs in the unreinforced embankment during an earthquake. The displacement exhibits an evidently irreversible accumulation with a fluctuation during the earthquake which is significantly dependent on the magnitude of input shaking. The peak strain of the geotextile exhibits a nearly triangular distribution in the vertical direction. The embankment can be divided into two zones, a restricting zone and restricted zone, where the soil and geotextile, respectively, play an active restriction role in the soil-geotextile interaction. The soil restricts the geotextile in the restricting zone, and this restriction is transferred to the restricted zone through the geotextile. The strain magnitude of the geotextile and the horizontal displacement of the geotextile-reinforced embankment decrease with increasing geotextile layers, with decreasing water content of the soil, with decreasing gradient of the slope, and with decreasing amplitude of the earthquake wave. 相似文献
168.
探讨Birla Excel纤维赛络针织纱的纺纱工艺.根据纤维断裂强度较高、伸长率较大且卷曲自然持久等特性,制定了合理的生产工艺,开清棉工序主要采取“多松少打、减少落棉、大隔距”的工艺原则,梳棉工序采用“轻定量、慢车速、隔距适中”的工艺原则,细纱工序采取优化工艺配置并选用J463型胶辊、重加压等措施提高成纱质量,同时采用低温蒸纱等措施解决成纱捻接强力不高的问题.通过实施一系列措施,生产的Birla Excel纤维赛络针织纱各项质量指标均达到了使用要求. 相似文献
169.
Slope stability problems of the weak rocks in the Asarsuyu pass of the Anatolian motorway 总被引:5,自引:0,他引:5
S. Dalgıç 《Bulletin of Engineering Geology and the Environment》1998,57(2):199-206
The Anatolian motorwaythrough the Asarsuyu Valley passes across landslides formed in amphibolites, metagranites and metadiorites
which have been extensively disturbed by past fault movements. The investigations indicated that the instabilities in the
valley could affect the proposed motorway. An attempt was made to establish the shear strength values of the 1200×750×130 m
Kom Rock Slide using the Hoek and Brown equation. The work indicated that this was not applicable in the highly sheared material
along the major fault zones.
28 February 1998 · Accepted: 9 June 1998 相似文献
170.
陕甘宁盆地中部大气田成藏条件分析 总被引:6,自引:0,他引:6
陕甘宁盆地大气田的发现既是天然气勘探上的突破又是对盆地天然气成藏条件认识上的转折,认识到受风化侵蚀的古台地才是盆地天然气勘探的目标。气田主要边界受夹持古台地的沟槽发育的控制:沟槽中早期充填石炭系煤系地层并成为煤成气向古台地溶孔运移的通道,燕山运功后,台地东侧的沟槽抬升成为天然气向东运移的天然屏障。文中论述了中部大气田两套气源岩、岩相与岩溶、风化壳地貌及靖边气田成藏、形成高产区的基本地质条件。最后对勘探远景作出评价。 相似文献