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121.
���ھ�������ʵ��۲�ȶ�   总被引:2,自引:0,他引:2  
???FG5???????????????????????2008??1?????й??????????о?????3053????????????????????????о?????????????????FG5-214??FG5-232???н???????????????????????????????????????н????????????????????????????????????2~3????10 -8 ms -2??  相似文献   
122.
由于存在部分泥岩井眼垮塌,东海春晓气田测井曲线砂泥岩阻抗部分叠置。针对这一现象,采用未垮塌段泥岩伽马与密度拟合关系校正垮塌段泥岩密度,声波时差经本区伽德那公式拟合后求取。通过泥岩垮塌测井数据校正前后对比、直方交会、岩石物理、正演及反演效果分析,认为校正后的测井数据比较真实地反映垮塌段扩径泥岩地层特征,储层与围岩波阻抗差异明显,为储层反演、砂体空间展布分析提供了有力依据。  相似文献   
123.
数码相机检验中出现的问题及解决方法   总被引:1,自引:0,他引:1  
数码相机的检验是近景摄影测量中经常碰到的问题。最常用的主要还是基于共线方程的后方交会法。但由于普通数码相机存在较大的镜头畸变,内方位元素也未知,所以仅用单片进行后方交会求取有关参数时,法方程可能会出现病态现象,从而影响最后的检验结果。文中对此现象进行了讨论,并给出了一些实用的解决方法。  相似文献   
124.
??10???????FG5-112?????????????й???????????????????о?????嶯??????????????????????68??????????ι????????????С??2??10 -8 ms -2???????????????????????С?????????????;????????????????????????????????????仯?????1??10 -8 ms -2 /a??????????λ???????-0.38 cm/a;??????????λ?仯??????????????????????????????  相似文献   
125.
��������ұ궨�Զ�����ϵͳ   总被引:1,自引:0,他引:1  
?????Я????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????  相似文献   
126.
??FG5??112?????????????й?????????????硱????????? ??JZ06????????4?ξ?????????????????????????????????????????????????????????????????????1??2001??2008??3?ι?????????????????20??10-8ms-2???????????????????????????????????????????15.4??10-8ms-2??????6.7??10-8??ms-2????2?????????仯??????????????????????????????????仯?????0.61??10-8ms????-2??/a???????????λ???????-0.18cm/a??????????????????仯??????????????????????????????????????????????????????  相似文献   
127.
Artificial neural networks are used to predict the micro‐properties of particle flow code in three dimensions (PFC3D) models needed to reproduce macro‐properties of cylindrical rock samples in uniaxial compression tests. Data for the training and verification of the networks were obtained by running a large number of PFC3D models and observing the resulting macro‐properties. Four artificial networks based on two different architectures were used. The networks used different numbers of input parameters to predict the micro‐properties. Multi‐layer perceptron networks using Young's modulus, Poisson's ratio, uniaxial compressive strength, model particle resolution and the maximum‐to‐minimum particle ratio showed excellent performance in both training and verification. Adding one more variable—namely, minimum particle radius—showed degrading performance. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
128.
现今绝对板块运动   总被引:1,自引:0,他引:1  
根据热点假设,热点对于中间层是固定的.相对热点的板块运动叫做绝对板块运动.绝对板块运动模型可以通过反演火山链传播的速率和走向数据以确定相对板块运动在角速度空间的原点来得到.利用一组近来(0~7.8 Ma)全球分布的热点的迁移速率和走向数据,结合板块运动模型NNR-NUVEL1A,已研制出一个叫做APM2的现今绝对板块运动模型.按照该模型,太平洋板块围绕60.063°S、102.210°E处的极以(0.833 0°±0.013 3°)/Ma的速率运动,非洲板块围绕46.849°N、44.372°W的极以(0.101 5°±0.013 4°)/Ma的速率运动,南极板块的运动则以46.871°N、146.942°E为极,速率为(0.084 6°±0.017 7°)/Ma,欧亚板块的运动更慢,极为27.291°N、171.925°W,速率为(0.065 5°±0.020 6°)/Ma.这一模型表明,岩石圈相对深部地幔有一个以49.423°S、90.625°E为极,速率为(0.198 3°±0.013 5°)/Ma的净旋转.表明太平洋热点同印度-大西洋热点不一致,显示太平洋热点的运动也不一致.为了分析和比较,还给出了仅用全球分布的热点的走向数据和仅用印度-大西洋热点的走向数据得到的板块绝对运动的角速度.  相似文献   
129.
The first application of the SHETRAN basin‐scale, landslide erosion and sediment yield model is carried out for a major landsliding event in the upper 505 km2 of the Llobregat basin, in the eastern Spanish Pyrenees, in November 1982. The model simulates the spatial distribution of shallow landslides and their sediment yield. Acknowledging uncertainty in the model parameter evaluation, the aim of the application was not to reproduce the observed occurrence of landslides as accurately as possible with one simulation, but to bracket the observed pattern with several simulations representing uncertainty in the key input conditions. Bounds on the landslide simulations were thus determined as a function of uncertainty in the vegetation root cohesion (used in the model factor of safety calculations). The resulting upper bound considerably overestimates the observed pattern (17 000 landslides compared with an observation of around 700), but it reproduces several of the principal clusters in the observed pattern. The lower bound contains around 500 landslides. The sediment yield estimates (2670–14 630 t km?2) are comparable to measurements elsewhere in the Pyrenees for extreme events. The results demonstrate an ability to simulate the basin‐scale landslide response to a rainfall event and the resulting sediment yield. They also highlight the need for further research in setting the uncertainty bounds and in avoiding large overestimates of landslide occurrence arising in part from a current inability to model small‐scale controls for a basin of the given size. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
130.
SARAL/AltiKa has a Dual Frequency Microwave Radiometer (DFMR), and Jason-2 has an Advanced Microwave Radiometer (AMR). Both microwave radiometer sensors include a 23.8 GHz primary water sensing channel. The measurement consistencies between DFMR and AMR are important for establishing a consistent altimetry data set between SARAL/AltiKa and Jason-2 in order to accurately assess sea level rise in a long-term time series. This study investigates the measurement consistency in the 23.8 GHz channel between DFMR and AMR at the Simultaneous Nadir Overpasses (SNO's) between the two satellites and also at coldest ocean brightness temperature locations. Preliminary results show that while both instruments show no significant trends over the one year since the launch of SARAL, a consistent relative bias of 2.88 K (DFMR higher than AMR) with a standard deviation of 0.98 K is observed. The relative bias at the lowest brightness temperature from the SNO method (-3.82 K) is consistent with that calculated from coldest ocean method (-3.74 K). The relative bias exhibits strong latitude (and scene temperature) dependency, changing from -3.82 K at high latitudes to -0.92 K near the equator. There also exists an asymmetry between the northern and southern hemisphere. The relative bias increases toward the lower end of brightness temperature.  相似文献   
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