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171.
In mountainous areas, it is the undulant terrain, various types of geomorphic and land use that make the remote sensing images great metamorphism. Moreover, due to the elevation, there are many areas covered with shadow, clouds and snow that make the images more inaccurate. As a result, it would be very difficult to carry out auto-classification of RS images in these areas. The study took Southwest China as the case study area and the TM images, SPOT images as the basic information sources assisted by the a... 相似文献
172.
主要对以色列野生二粒小麦赫尔蒙种群中分离获得的一个抗条锈病基因进行了分子定位研究 ,将源于赫尔蒙山具抗杀锈病的种系 T.dicoccides H52与普通的栽培种 Langdon进行杂交并创建了 F2 代遗传图。研究发现 H52种系抗条锈病的能力由一种显性基因控制 ,将其暂定名为 Yr H52。从 1 2 0个微卫星标记中 ,已经检测到来自亲本 91 %的多态性 ,而且从其中 56个微卫星分子标记中产生了 79个分离的位点 ,有 9个位点显示出了与 Yr H 52基因连锁 ,其重组率 0 .0 2~ 0 .3 5,遗传距离 2 .0 0~ 4 3 .3 7cm之间 ,L OD值 3 .56~ 54.2 2。由 1 0个微卫星位点和 Yr H52构建的染色体 1 B遗传图 ,其图距全长为 1 0 1 .5cm。Yr H52基因位于 Xgwm2 64 a和 Xgwm2 64 c之间 ,且与 Xgwm2 64 a、Xgwm1 8紧密连锁 ,两侧依次分别与 Xgwm1 3 1 a、Xgwm63 6b、Xgwm2 64 c、Xgwm4 0 3 a、Xgwm1 53、Xgwm550 a和 Xgwm1 2 4连锁。同时 ,Yr H52也与 REL P标记物 N or1紧密连锁 ,图距 1 .4 cm,L OD2 9.62。这显然与野生二粒小麦另一个抗条锈病基因 Yr1 5不同 ,研究证明 Yr1 5与 N or1图距是 1 1 .0 cm。 相似文献
173.
A numerical wave flume is constructed based on the Reynolds Averaged Navier-Stokes (RANS) equations with turbulence closure by a modified k-ε model to study the viscous interactions of waves with vertical breakwaters for different overtopping cases. The governing equations,the turbulence model,boundary conditions,and solution method for the numerical wave flume are introduced briefly. The reliability of the numerical wave flume is examined by comparing the numerical results with the experimental measurement... 相似文献
174.
A total of 34 thunderstorms around Shanghai and Wuhan of China are analyzed in order to determine the relationship between total lightning activity and precipitation particle characteristics.Precipitation particle concentration data are obtained from the 2A12 product of TRMM/TMI(Tropical Rainfall Measuring Mission/TRMM Microwave Image) and lightning activity data are from the TRMM/LIS(Lightning Imaging Sensor) and SAFIR3000(Surveillance et Alerte Founder par Interferometric Radioelectirque).On a spatial ... 相似文献
175.
本文介绍由重磁资料计算上海地区居里面、莫霍面、均衡重力异常及地幔流应力场的方法和成果,并在对成果初步分析的基础上,探讨了深部地质构造特征及其与地震活动趋势的关系,其中着重讨论了居里面及其与地震活动的关系。文章最后提出了对上海地区地震活动趋势的几点认识。 相似文献
176.
简述了原国家重力基本网(57网)的历史和技术要点,详细地分析了57网的各类误差和产生原因,提出了新、旧系统转换的方法。本文研究表明,57网基本点相对观测的实际精度约为±0.06mgal,仪器平均值误差为1.6×10~(-4)。基本点重力值含-13.56mgal的基准误差和1.9×10~(-4)的尺度差,并含有±0.1~0.2mgal的非线性系统误差。对基本点实行新、旧系统转换误差为±0.05mgal,基本不损失其观测精度。 相似文献
177.
Guo XuequanSoutheast Hubei Geological Party Hubei Bureau of Geology Mineral Resources Daye Hubei 《《地质学报》英文版》1994,68(3)
This paper discusses geological-geophysical-geochemical models of such typical deposits as the Tieshan-type Fe-Cu deposit, the Tonglushan-type Cu-Fe deposit, the Yehuaxiang-type Cu deposit, the Jiguanzui-type Cu-Au deposit, and the Tongshankou-type Cu (Mo) deposit. The models were established based on practical data of the polymetallic deposits dominated by copper ore in southeastern Hubei. These models, which are graphically illustrated in the paper, systematically summarize the metallogenic geological conditions and the geophysical-geochemical characteristics of copper deposits in this area. The models are of practical significance for studying copper deposits, predicting mineral resources, choosing exploration methods, and searching for ore deposits based on existing ones in the study area. 相似文献
178.
Huang Liren Zhao Chengkun Hu Huimmg Yang Guiye Cao XiangchunFirst Land Deformation Monitoring Center SSB Tianjin China Surveying Mapping Bureau of Tianjin Municipality Tianjin China 《中国地震研究》1994,(3)
In this paper,a study of the principal characteristics of the ground deformation disasters in the city of Tianjin caused by the Tangshan earthquake is based on the results from the recent remeasurements of the geodetic controlling network of Tianjin and from on-site investigations after the earthquake.These results show that only the ground deformation in the Ninghe and Hangu areas near the epicenter reflect directly the co-seismic crustal stress,while the serious ground deformation and the engineering earthquake damages in the urban districts of Tianjin are controlled to a great extent by the local engineering geological structures,showing a kind of secondary disaster.Several suggestions are also proposed in the paper concerning the counter-measures for reducing the earthquake damage in big cities. 相似文献
179.
You Lilan Liu Dajie Huang Jia'na Liu Xue Zhou KechangInstitute of Crustat Dynamics SSB Beijing China Wuhan Technical University of Surveying Mapping Wuhan China National Center for Seismic Data Inforraanon SSB Beijing China 《中国地震研究》1994,(3)
This paper makes a probe into the application of the Kalman filtering method to the data processing of across-fault measurements.On the basis of statistical regression,the mathematic and stochastic models of filtration are established by combining the regression method with Kalman filtering.In the filtering computation,not only the randomness of fault movements but also the time-dependent variation of environmental effects have been taken into consideration.By use of the adaptive filtering method,an estimation of the dynamic noise variance matrix is obtained through iteration.Models for one measuring line(leveling line or baseline),two measuring lines(both leveling lines or both baselines)and four measuring lines(two leveling lines and two baselines)are derived and established systematically.By means of these models,the data of across-fault measurements can be processed dynamically in real-time to provide the filtered values of height difference between benchmarks or baseline length at different time in 相似文献
180.
Zhao Yanlai Sun Ruomei Mei ShirongCenter for Analysis Prediction SSB Beijing China Institute of Geophysics Academia Simca Beijing China 《中国地震研究》1994,(4)
In this paper a method of relocating hypocenter in inhomogeneous medium is introduced.Based on the velocity from the latest results on the crust and mantle structure of the Bohai Sea and its adjacent areas,by using the data recorded in Shandong,Hebei,Beijing,and Liaoning networks around the Bohai Sea we apply the method to relocate hypocenter parameters of 598 events occurring in the Bohai Sea and its adjacent areas.The accuracy of hypocenter relocation is discussed.We present the results of events ML≥4.0 in the Bohai Sea in recent years and discussed the distribution of focal depths. 相似文献