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排序方式: 共有148条查询结果,搜索用时 15 毫秒
1.
通过对尚家—太平川地区构造演化、烃源岩特征、沉积特征、储盖组合、油水关系及油藏类型和油气成藏特征的分析,研究了本区的石油地质条件,认为烃源岩具有较好的生、排烃能力,分流河道砂体为油气聚集提供较好的沉积环境,良好的储盖组合有利于油气的聚集与保存。研究区没有统一油水界面,尚家地区以岩性—构造油藏为主,太平川地区以构造—岩性油藏为主。区内扶余—杨大城子油层油气成藏受有效性圈闭、优势运移通道、过剩压力、储集条件和构造诱导作用控制。据上述认识确定了研究区下一步的勘探方向,并已在指导勘探实践中取得了较好的效果。 相似文献
2.
Recently, multi-layered targets have become commonplace in both military and civilian applications, such as marine hulls, armored vehicle bodies, outside structures of bulletproof cars, and aerospace vessels. This paper studies the resistant performance of perforation in multi-layered targets. An estimation procedure is established based on the concepts of the conservation of momentum, impulse-momentum law, and conservation of energy. Experimental results of the test of Almohandes et al. are adopted to check the residual velocity of multi-layered targets. The results of the verification are good in terms of agreement for impact velocities ranging from 700 to 800 m/s, when the ratio of the projectile length to the projectile diameter (i.e. L/D) is 4.2, and the average residual velocity error of single, double- or triple-layered targets range approximately from 4.42 to 8.40%. The ballistic performance is best for the double target when the ratio of the first layer thickness to the total thickness (i.e. t1/(t1+t2)) is about 0.75, and the worse performance occurs when the ratio t1/(t1+t2) is 0.5. An air gap slightly influences the resistant performance of perforation in multi-layered targets. These results may serve as a useful reference for designers. 相似文献
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We report on an objective methodology, referred to as intrinsic sample methodology, for the delineation of exploration target areas or resource areas for assessment. Important features of the methodology include (1) identification of recognition criteria for critical genetic factors, (2) synthesis of new variables from enhanced geodata, (3) estimation of logit probability models, and (4) cutting of estimated logit probabilities to delineate exploration targets or resource areas. The methodology is demonstrated on the Walker Lake quadrangle of Nevada and California. 相似文献
6.
圆形标志中心子像素定位方法的研究与实现 总被引:18,自引:1,他引:18
黄桂平 《武汉大学学报(信息科学版)》2005,30(5):388-391
采用回光反射材料制作圆形回光反射标志,经摄影后得到标志的“准二值影像”;对标志的椭圆影像进行亚像素边缘提取,经最小二乘椭圆拟合后得到标志中心的子像素级位置。试验表明,可以达到0.02像素的定位精度。 相似文献
7.
采用RAMAC/GPR探地雷达对机场跑道传力杆进行探测试验,取得了令人满意的效果,为机场工程质量检测提供了一种有效手段。 相似文献
8.
甘肃桦树沟(铁)铜矿床的成因机制 总被引:4,自引:0,他引:4
矿床地质地球化学特征研究结果表明,随着古陆边缘弧-槽-盆体系的发生与发展,元古代基底火山(沉积)岩系经深循环水(海水)-热系统的作用,成矿物质被浸出和搬运,并经海底喷溢作用沉淀于海盆洼地中形成桦树沟矿床含铜建造,后期变质作用使成矿物质活化、转移和富集。桦树沟矿床为喷气(流)沉积-变质改造型(铁)铜矿床。 相似文献
9.
基于灰度形态学的高分辨率遥感影像预处理 总被引:6,自引:0,他引:6
提出了一种从高分辨率遥感影像中提取线性目标时影像预处理的方法。该方法基于灰度形态学的Top-Hat运算和灰度膨胀运算,用Top-Hat算子除去影像的噪声,再利用灰度膨胀增强影像目标和背景之间的对比度,使目标更易于识别。经过处理的遥感影像,能够更有效地提取影像的目标。 相似文献
10.
For surface features in short-wave infrared (SWIR, 1.3–3.0 μm) in remote sensing imagery, pixel values depict the total energy including reflection and emission. For surface features at normal temperature in SWIR band, emission energy can be ignored. While for surface features at high temperature in SWIR band, emission energy is equal to or even higher than the reflection energy. So remote sensing imagery of SWIR band can be used to separate emission and reflection energy as well as to realize temperature retrieval of high temperature targets. In this study, the seventh band (SWIR band) of Landsat8 OLI remote sensing imagery is used to perform the theoretical model research for temperature retrieval of high temperature targets. In the meantime, it is also used with the corresponding observation experiment of synchronization satellite to check the theoretical model. The result shows that the radiant flux density for mixed pixels with high temperature targets is higher than adjacent pixels without high temperature targets. Thus, the high temperature pixels can be identified in SWIR band. The retrieval results of temperature and fractional area for high temperature targets are consistent with reality. In the study, the result illustrates that it is effective to identify high temperature targets in remote sensing imagery of SWIR band and the model is appropriate for temperature retrieval use. 相似文献