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71.
基于EMD与神经网络的机械故障诊断技术   总被引:2,自引:0,他引:2  
经验模式分解 (EMD)是分析非线性、非平稳信号的有力工具 ,它将信号分解为突出了原信号的不同时间尺度的局部特征信息的内在模函数 (IMF)分量。本文通过将各 IMF分量输入到 BP网络中进行训练学习和故障诊断 ,比直接输入原信号可以提高 BP网络对故障诊断的准确率 ,而且减少了训练时间。  相似文献   
72.
以 CG2 0潜山为例 ,从建立地质模型入手 ,包括地层模型、构造模型、储集模型、储盖组合模型、速度模型等 ,认识到各套地层分布和储层物性的差异均与地震响应密切相关 ,因此可以利用地震波的信息 ,预测潜山储层的发育及分布情况。在对 CG2 0潜山进行精细全三维构造解释的基础上 ,探讨性地应用了测井约束反演、吸收系数、相干分析及三维模式识别等技术 ,对潜山储层进行了预测 ,从而提高了潜山勘探的效益 ,并为类似断阶型潜山带的勘探提供了成功的经验 ,具有一定的指导意义。  相似文献   
73.
青岛胶州湾3.2级地震构造背景与控震断裂   总被引:1,自引:0,他引:1  
本文应用构造分析的方法 ,对青岛胶州湾 3.2级地震发生的地震地质背景和构造背景进行分析。结果表明 :胶州湾 3.2级地震主要受 NEE向郝官庄断裂和 NNW向大沽河断裂控制 ,并根据现代活动断裂的标志 ,对上述 2组断裂活动性特征作了阐述  相似文献   
74.
Morphologic studies of an oceanic transform, the Blanco Transform Fault Zone (BTFZ), have shown it to consist of a series of extensional basins that offset the major strike-slip faults. The largest of the extensional basins, the Cascadia Depression, effectively divides the transform into a northwest segment, composed of several relatively short strike-slip faults, and a southeast segment dominated by fewer, longer faults. The regional seismicity distribution (m b 4.0) and frequency-magnitude relationships (b-values) of the BTFZ show that the largest magnitude events are located on the southeast segment. Furthermore, estimates of the cumulative seismic moment release and seismic moment release rate along the southeast segment are significantly greater than that of the northwest segment. These observations suggest that slip along the southeast segment is accommodated by a greater number of large magnitude earthquakes. Comparison of the seismic moment rate, derived from empirical estimates, with the seismic moment rate determined from plate motion constraints suggests a difference in the seismic coupling strength between the segments. This difference in coupling may partially explain the disparity in earthquake size distribution. However, the results appear to confirm the relation between earthquake size and fault length, observed along continental strike-slip faults, for this oceanic transform.  相似文献   
75.
台湾海峡及其西边地区正常地震动态及危险性特征   总被引:1,自引:2,他引:1  
柯龙生  林世敏 《台湾海峡》1994,13(2):190-197
本文从地震的时,空分布特征,区域应力场动态,能量释放方式,b值及震群特征6个方面研究了台湾海峡及其西边地区地震活动的正常动态及异常特征。结果表明,具有前兆意义的变化模式表现为区域地震活动在时间,空间及功能方面的有序性变化,即:(a)地震空间分布由分散转为集中,形成条带或空区;(b)断裂活动由多组转为单一,应力场趋向一致;(display status  相似文献   
76.
Since the beginning of formation of Proto-Taiwan, the subducting Philippine (PH) Sea plate has moved continuously through time in the N307° direction with respect to Eurasia (EU), tearing the EU plate. The subducting EU plate includes a continental part in the north and an oceanic part in the south. The boundary B between these two domains corresponds to the eastern prolongation of the northeastern South China Sea ocean-continent transition zone. In the Huatung Basin (east of Taiwan), the Taitung Canyon is N065° oriented and is close and parallel to B. Seismic profiles show that the southern flank of the canyon corresponds to a fault with a normal component of a few tens of meters in the sediments and possible dextral shearing. Several crustal earthquakes of magnitude >%6 are located beneath the trend of the Taitung Canyon and focal mechanisms suggest that the motion is right-lateral. Thus, faulting within the sedimentary sequence beneath the Taitung Canyon is a consequence of underlying dextral strike-slip crustal motions. As the continental part of the EU slab located north of B has been recently detached, some subsequent dextral strike-slip motion might be expected within the EU slab, along the ocean-continent transition zone, which is a potential zone of weakness. We suggest that the dextral strike-slip motion along the ocean-continent boundary of the EU slab might trigger the observed dextral strike-slip motion within the overlying PH Sea crust and the associated faulting within the sediments of the Huatung Basin, beneath the Taitung Canyon. An erratum to this article is available at .  相似文献   
77.
提出了一种断层处理新方法——分块法与断层恢复法合成算法,这种方法兼有分块法与断层恢复法的优点同时又克服了其不足,较好地解决了含逆断层时煤层底板等高线自动绘制及任意边界的构网问题,使绘出的等值线图误差较小,更加符合实际。  相似文献   
78.
Cap-rock seals can be divided genetically into those that fail by capillary leakage (membrane seals) and those whose capillary entry pressures are so high that seal failure preferentially occurs by fracturing and/or wedging open of faults (hydraulic seals). A given membrane seal can trap a larger oil column than gas column at shallow depths, but below a critical depth (interval), gas is more easily sealed than oil. This critical depth increases with lower API gravity, lower oil GOR and overpressured conditions (for the gas phase). These observations arise from a series of modelling studies of membrane sealing and can be conveniently represented using pressure/ depth (P/D) profiles through sealed hydrocarbon columns. P/D diagrams have been applied to the more complex situation of the membrane sealing of a gas cap underlain by an oil rim; at seal capacity, such a two-phase column will be always greater than if only oil or gas occurs below the seal.These conclusions contrast with those for hydraulic seals where the seal capacity to oil always exceeds that for gas. Moreover, a trapped two-phase column, at hydraulic seal capacity will be less than the maximum-allowed oil-only column, but more than the maximum gas-only column. Unlike membrane seals, hydraulic seal capacity should be directly related to cap-rock thickness, in addition to the magnitude of the minimum effective stress in the sealing layer and the degree of overpressure development in the sequence as a whole.Fault-related seals are effectively analogous to membrane cap-rocks which have been tilted to the angle of the fault plane. Consequently, all of the above conclusions derived for membrane cap-rocks apply to both sealing faults sensu stricto (fault plane itself seals) and juxtaposition faults (hydrocarbon trapped laterally against a juxtaposed sealing unit). The maximum-allowed two-phase column trapped by a sealing fault is greater than for equivalent oil-only and gas-only columns, but less than that predicted for a horizontal membrane cap-rock under similar conditions. Where a two-phase column is present on both sides of a sealing fault (which is at two-phase seal capacity), a deeper oil/water contact (OWC) in one fault block is associated with a deeper gas/oil contact (GOC) compared with the adjacent fault block. If the fault seal is discontinuous in the gas leg, however, the deeper OWC is accompanied by a shallower GOC, whereas a break in the fault seal in the oil leg results in a common OWC in both fault blocks, even though separate GOC's exist. Schematic P/D profiles are provided for each of the above situations from which a series of fundamental equations governing single- and two-phase cap-rock and fault seal capacities can be derived. These relationships may have significant implications for exploration prospect appraisal exercises where more meaningful estimates of differential seal capacities can be made.The membrane sealing theory developed herein assumes that all reservoirs and seals are water-wet and no hydrodynamic flow exists. The conclusions on membrane seal capacity place constraints on the migration efficiency of gas along low-permeabiligy paths at depth where fracturing, wedging open of faults and/or diffusion process may be more important. Contrary to previous assertions, it is speculated that leakage of hydrocarbons through membrane seals occurs in distinct pulses such that the seal is at or near the theoretically calculated seal capacity, once this has been initially attained.Finally, the developed seal theory and P/D profile concepts are applied to a series of development geological problems including the effects of differential depletion, and degree of aquifer support, on sealing fault leakage, and the evaluation of barriers to vertical cross-flow using RFT profiles through depleted reservoirs. It is shown that imbibition processes and dynamic effects related to active cross-flow across such barriers often preclude quantitative analysis and solution of these problems for which simulation studies are usually required.  相似文献   
79.
Risk Assessment for Tuzla Naval Base Breakwater   总被引:5,自引:0,他引:5  
1 .IntroductionTurkeywasstruckbytwomajorearthquakeeventsonAugust 1 7thandNovember 1 2th ,1 999,namedIzmit (Mw=7.4 )andD櫣zce (Mw=7.2 )earthquakes,respectively .ThestationsoperatedbytheGeneralDirectorateofDisasterAffairs,theKandilliObservatoryandEarthquakeResearchInstituteofIstanbulTechnicalUniversitymeasuredatleast 2 7stronggroundmotionsfortheIzmitearthquakewithin 2 0 0kmofthefault.AsignificantsegmentofthefaultrupturedintheareabetweenthewestofGolcukandtheeastofLakeSapanca .Inthesou…  相似文献   
80.
Study on Key Technology of Using Shell Sand as Backfill for Sea Reclamation   总被引:1,自引:0,他引:1  
1 .IntroductionEpicontinental sea or land could formfromcontinental shelf because of the decreasing sea levelduring Quaternary.There is a large-area shell sand deposit more than ten meters thick in the neriticzone of China .To use the abundant marine shell sandresource as engineering material for ocean engi-neering and port engineeringis veryimportant .Sand (Gred and Bjorn,1999) ,fine sand (Zhangetal .,2002) , mediumand coarse sand (Qiuet al .,1995) ,highly weathered stone ballast (Zhanetal…  相似文献   
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