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961.
文中描述了华南暴雨试验多普勒天气雷达数据的处理方法,建立了一套集图像显示、数据预处理及风场反演分析为一体的多普勒天气雷达的分析应用系统。该系统生成了三维正方形网格和经纬度网格的回波强度值,以及经噪声控制和速度扩展的径向速度风场,提交了华南暴雨试验雷达数据库。该文以1998年6月9日08:00(北京时) 探测数据为例,给出了华南暴雨试验区内4部多普勒天气雷达的反演雨强图和两部雷达的风场反演拼图,并进行了暴雨中尺度风场结构的初步分析。 相似文献
962.
Structural fabric of the Central Metasedimentary Belt of southern Ontario, Canada, from deep seismic profiling 总被引:1,自引:0,他引:1
The Central Metasedimentary Belt boundary tectonic zone (CMBbtz) is a 10–20-km-wide zone of intense structural deformation within the 1.3–1.0 Ga Grenville orogen of southeastern Canada. The crustal structure of the exposed CMBbtz has been well studied, but its sub-Phanerozoic location and geometry beneath the urban development and nuclear stations of the Toronto region are not well known. A new 75-km Lithoprobe reflection profile acquired close to Toronto provides a clear image of the CMBbtz as a panel of southeast-dipping reflections that extends with moderate dip (<25°) to mid-crustal depth (25 km). These dipping reflections truncate and (or) overprint a subhorizontal band of reflectivity at 21 km depth. The seismic line is oblique to the major structural trends; cross-dip analysis shows that the southeast-dipping reflections have a strike and dip of N13°E and 25°, whereas the “subhorizontal” reflections strike and dip at N65°E and 20°, respectively. Both of these bands of reflectivity can be correlated to magnetic anomalies in the CMBbtz or its immediate footwall. Magnetic anomalies with similar strike directions are well expressed within a distinct rhomboid-shaped region (106×109 km) in the subsurface of western Lake Ontario, herein named Mississauga domain. Taken together, the seismic and magnetic data are inconsistent with existing models, in which the CMBbtz is extrapolated beneath Lake Ontario along a linear magnetic anomaly. We propose a revised subsurface trace of the CMBbtz along the western edge of the Mississauga domain. Small earthquakes in western Lake Ontario appear to cluster along trends co-linear with ENE magnetic anomalies, suggesting a possible degree of basement tectonic control on local intraplate seismicity. 相似文献
963.
Jennifer Mack 《Singapore journal of tropical geography》2004,25(2):156-179
Batam Island, Indonesia, located a short ferry ride away from Singapore, is a place where tourism and industry have been developed simultaneously and a border area where “developed” and “developing” nations meet. Government officials, investing international corporations and the “factory women” who work in the island's industrial estates arrive in Batam ‐ native to none of them ‐ with their own preconceptions and goals. When challenges not foreseen through master planning arise, the authorities cling ever more tightly to their physical and structural development model: the nearby city‐state of Singapore. Conversely, the factory workers who travel intranationally to work in this export processing zone (EPZ) find their objectives contested in the face of the Master Plan, corporate agendas and ethnic fusions characterising this transnational capitalist space. Entering into the homes of three groups of women migrants living and working in Batam, the relationship between the private realm that they inhabit and the social contexts in which they participate publicly is investigated. Some of the choices that women make at and about home are identified, and their ability to “micro‐resist” these external structures is explored. At home, the dynamic relationship between the Batam development project and the women's own hopes and visions of the place ‐ sometimes parallel and sometimes incongruous ‐ are revealed. As they experience life on Batam, their “social imaginaries” of it are shaped into various new realities, and their homes, removed from the confines of the factory floor, thus become spaces of release from these tensions. 相似文献
964.
965.
扎赉诺尔煤业集团铁北矿勘探区目的层埋藏浅,地表条件复杂,成孔困难,很难到达激发层位,反射波能量及高频成分衰减大,对地震资料的信嗓比和分辨率降低。为此,经多次试验,在野外数据采集中采用合理的观测系统及相应的技术措施,资料处理和资料解释方法、流程得当,在勘探区钻孔资料少的情况下,保证了目的层速度场反演的准确性,取得了较好的地质效果。经矿井和生产实际验证,三维地震资料的精度较高。 相似文献
966.
967.
对受洪水涨落率影响、下游支(干)流洪水顶托影响及人工水利工程影响的水位流量关系,提出了用计算机综合处理的校正因数一落差指数拟合法,较好地解决了水位流量关系单值化的问题,满足现行的《水文资料整编规范》要求,具有一定的推广价值。 相似文献
968.
969.
数字图像处理技术在钢坯在线检测系统中的应用 总被引:4,自引:0,他引:4
介绍了钢坯在线测宽测厚系统的基本原理和系统组成。同传统的接触式测量相比,本系统利用红外热成像,通过计算和寻找梯度最大值进行钢坯边缘检测,根据梯度对边缘进行亚像素细分,对钢坯宽度和左右厚度尺寸进行实时测量。提出了非接触式钢坯尺寸测量中一种新的边缘检测方法,并从理论和生产实践上证明了该方法的可行性和正确性。 相似文献
970.
测绘专业《计算方法》课程教学方法初探 总被引:1,自引:0,他引:1
数据处理是测绘专业学生必须掌握的技术,测绘专业的《计算方法》课程就是为了加强学生这种技术能力的培养所开设。本文针对测绘专业的计算方法课程所存在的一些问题,在教学内容取舍,习题布置,上机实践以及考试方式等方面进行了探讨。 相似文献