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61.
油水层快速识别改进的CP网络方法初探   总被引:1,自引:0,他引:1  
CP网络具有分类快速、准确等优点。文中详细介绍了CP网络的算法,并对其进行了部分改进,增加了误差检验和网络测试功能;使用VisualBasic6.0开发了相应仿真软件,并将其用于某油田的油、水层快速识别。实际应用表明:改进的CP网络训练周期短、识别准确率高,完全可以用于油、水层等的快速识别,具有广阔的应用前景。  相似文献   
62.
通过对频率测深理论的研究,提出了水平电偶极场视电阻率改进滤波算法,并编制了正演计算的实用程序。理论模型计算表明,改进滤波算法 效果好,计算速度快。  相似文献   
63.
小兴安岭地区黑河-北安段多年冻土分布特征   总被引:7,自引:4,他引:7  
张艳  吴青柏  刘建平 《冰川冻土》2001,23(3):312-317
对于寒区公路工程,查清冻土工程地质条件是至关重要的,利用地质雷达和探孔来研究多年冻土的分布,为路基设计和处理提供依据,研究结果表明,黑北段分布有17段岛状年冻土,总长度为3.165km,主要分布于沼泽化湿地、泥炭层和草炭层极为发育低洼地带、多年冻土上限约1.5-2.0m,多年冻土厚度3-6m,主要发育有多冰冻土、富冰冻土、饱冰冻土,多年冻土地温较高,热稳定性较差,多年冻土处于强烈的退化状态。  相似文献   
64.
Considering the fact that there is only one pair of fixed potential poles in one direction used to monitor the resistivity changes under the observatory station which may indicate process of earthquake preparation, based on the precondition that the resistivity structure is 1-dimensional under the observatory station, and by way of equivalent model put forward by the authors, this paper suggests a kind of method trying to separate the resistivity changes in deep layers from that of the shallow layer. Analysis shows that, to obtain the same measured data with the same array, any a multi-layered geo-electrical structure can be equivalently taken as a two-layered one, we call it equivalent model. In this paper, the resistivity and thickness of the upper layer of the equivalent model are equal to that of the first layer of the original one, the resistivity of the lower layer of the equivalent model is obtained with calculation according to the requirement of equivalence, its value is relevant with the resistivities and thicknesses of all layer of the original model except for the first one, so the resistivity change of the equivalent layer can indicate the synthetic effect of variation of all layers of the original model except for the first one. The primary research results show that this method can work well. Foundation item: Chinese Joint Seismological Science Foundation (100146).  相似文献   
65.
INTRODUCTIONSeveMmethdsdPOtential analyslsfor medium-and short-termpredlctlon dl’l;lln shocks weredevelopedbaseduponthe pnnclpledInaccufatemeasurementoffOCfOCustheoryaMthepattemdmainshocks.These analytic methods can be used to predict strong earthop拙es In shallow layers on thesubducting plate boundeq In squeezed zones.More than a half of strong earthquakes In the world。located inthe shallow depth tthe suMuctingplate boundw In s仰eezed zones.This paPerfirst Statesthe philoso…  相似文献   
66.
湖南洞庭坳陷大地电磁测深研究   总被引:1,自引:0,他引:1  
魏文博  张先觉 《现代地质》1996,10(4):532-542
介绍了大地电磁测深在湖南洞庭坳陷的主要研究成果。详细分析、推断了洞庭地区的区域构造格局,深部电性结构及壳、幔高导层的分布特点  相似文献   
67.
The deformation of movable boundaries under the action of an applied turbulent shear stress is well known. The resulting bed forms often are highly organized and nearly two-dimensional, which makes them an intriguing focus of study considering that they are generated in both steady and oscillatory turbulent flows. Many past studies share a common approach in which an infinitesimal perturbation is prescribed and the resulting growth or decay patterns are examined. In this approach, the bed forms are usually sinusoidal and the perturbation analysis does not provide a theoretical prediction of equilibrium bed-form geometry. An alternative approach is suggested here in which the forcing terms (pressure and stress) are prescribed parametrically and the governing equations are solved for the flow velocity and the associated boundary deformation. Using a multilayered approach, in which the bottom boundary layer is divided into a discrete, yet, arbitrary number of finite layers, analytical solutions for the horizontal current and bed profile are derived. The derivations identify two nondimensional parameters, p0/u02 and 0/kh0u02, which modulate the amplitude of the velocity fluctuations and boundary deformation. For the case of combined pressure and stress divergence anomalies, the magnitude of the front face and lee slopes exhibit an asymmetry that is consistent with observed bed forms in steady two-dimensional flows.Responsible Editor: Jens Kappenberg  相似文献   
68.
We conducted a statistical analysis of the physical characteristics of the micropulsation activity (Pc3 and Pc4 range) detected, during the austral summer 1994/95, at Terra Nova Bay (Antarctica, corrected latitude 80.0°S), a station which is few degrees poleward of those where most of the Antarctic measurements in these frequency ranges have been performed. The emerging overview suggests that the correspondence between the pulsation power and the external parameters (solar wind speed, interplanetary magnetic field magnitude and orientation) is significantly stronger than at somewhat lower latitudes. The day-to-day power variability was found to be strictly related to the general level of the geomagnetic activity, and the power level sharply maximizes at local magnetic noon. In the Pc4 range peaks of correlation with the SW speed are found in the dawn and dusk sides of the Earths magnetosphere and the daily variation of the polarization pattern is closely consistent with that found at auroral latitudes and at lower frequencies. In the Pc3 range the correlation coefficient between the pulsation power and the SW speed has maximum values in the local morning, and the frequency of selected events reveals a strong IMF control during closed magnetospheric conditions. The local time dependence of the correlation coefficient between the pulsation power and the cone angle reveals an additional control by the IMF orientation, which becomes more explicit around local noon.  相似文献   
69.
通过对上海轨道交通9号线宜山路车站深基坑降水试验结果分析,得到不同土层受降水影响的岩土工程特征,并对个别土层的实测沉降与由室内试验参数进行估算的沉降进行比较,以获得真实的沉降影响状况,指导深基坑的设计和施工。  相似文献   
70.
张庆云  常蕊 《大气科学》2007,31(6):1160-1170
利用1971~2000年逐月SODA (Simple Ocean Data Assimilation) 同化资料(Carton等,2004)、1980~2000年逐月NCEP/NCAR再分析资料(Kalnay等,1996)探讨中部型(暖海水首先出现在120°W以西)和东部型(暖海水首先出现在120°W以东)El Ni?o事件赤道纬向风应力及洋流的异常变化与暖海水信号的传播特征。研究指出:(1)中部型和东部型El Ni?o事件发生时,太平洋上赤道海表最大西风应力距平在西太平洋地区都有显著的东传现象,但中部型El Ni?o事件西风应力距平强度强,造成西太平洋赤道表层的东向流可达东太平洋地区,这类El Ni?o事件强度偏强。(2)中部型El Ni?o事件,赤道表层洋流辐合区及其下沉运动由西太平洋向东太平洋传播,辐合下沉运动抑制了深层冷海水上翻,西太平洋暖水能够传到东太平洋与西太平洋赤道表层洋流辐合区及其下沉运动的东移有关。(3)东部型El Ni?o事件西太平洋赤道表层洋流辐合区及其下沉运动没能直接传到东太平洋地区,东太平洋暖水形成与局地(120°W以东)辐合下沉运动抑制深层冷海水上翻有关;东部型El Ni?o事件暖池次表层的暖水,不是沿着西太平洋赤道次表层向东传播到东太平洋地区,而是由南太平洋西边界流将暖池海水带到40°S左右的西风漂流区, 再由西风漂流平流到东太平洋。  相似文献   
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