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201.
在CDSN台站用数字滤波方法对数字地震仪进行抑制噪声滤波,方法简单易行。通过震例检验,把本人新创造的滤波器用ARS软件中含有的滤波器相结合,对地震信号的识别有一定的参考意义,有助于提高编辑地震报告的P波利用率。 相似文献
202.
Wilfried Heller 《GeoJournal》1998,46(3):199-205
This study evaluates some aspects of the socio-economic transformation of rural Romania with reference to the views of representative
organisations (at national, regional and local levels) and other experts. Interviews conducted in ten communes of nine Romanian
counties (‘judete’) focus attention on the advantages and disadvantages of system change experienced since 1989; the most
important problems and constraints for future socio-economic change; and appropriate policies and perspectives for development
in the immediate future. Wherever appropriate the claims of interviewees are substantiated through reference to statistics,
drawn in many cases from Chambers of Commerce & Industry (CCI). Local level representatives presented much more negative views
on recent change than their national and regional level counterparts, but all agreed on the crucial problem of capital shortage.
Thus while specific programmes to assist rural areas are justified, they cannot fully succeed until the national economy is
able to grow more rapidly and attract greater foreign investment.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
203.
由于数字地震记录仪具有记录频带宽,分辨率高,动态范围大以及易于用计算机处理等优点,所以数字地震台网产出的数字地震资料成为地震活动性,震源机制,地球内部研究,地震监测及预报等的最基本数据源。 相似文献
204.
《Marine Policy》2015
What have been the moral values and practices allowing equitable economic opportunities and a sense of fairness in North American small-scale fisheries? How have these “moral economies” been affected by neoliberal policies with their emphasis on efficiency, rational self-interest, and wealth accumulation? Focusing especially on the salmon and halibut fisheries in British Columbia, Canada, this discussion summarizes key findings on the manner in which small-scale fisheries and their moral practices tend to be marginalized and undervalued under neoliberal regimes. The paper considers the value of these moral economies for promoting social, economic, and ecological welfare as grounds for the expansion of small-scale fisheries. 相似文献
205.
This article presents the developments of an ongoing research aimed at modelling the influence of fissuring on the behaviour of clays. In particular, it recalls the main results of an extensive laboratory investigation on a fissured bentonite clay from the south of Italy and presents the data of a new investigation on the evolution with shearing of the strain fields developing within the clay, resulting from Digital Image Correlation (DIC). Element test results are analysed in the framework of continuum mechanics and linked to the clay fissuring features, once characterised using the Fissuring IDentity (F‐ID) chart. This article compares the bentonite behaviour with that of other fissured clays of different F‐IDs, highlighting the common behavioural features. Thereafter, the soil response at the macro level is related to the DIC‐derived strain fields evolving within the clay with loading. For this purpose, DIC was successfully used to investigate the deformation processes active in the fissured clay and the sources of the localisation phenomena. DIC is shown to provide indications of the extent to which highly to medium fissured clays element test results can be of use to model the clay behaviour according to continuum mechanics. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
206.
207.
The post depositional thermal maturity and its related chemical changes induce the sporomorphs color alteration, which is a common useful tool in the optical microscopy of the organic matters (OM) and their pre-geochemical studies. The present contribution uses the modern available opportunity of digital technology to achieve a quantifying system technique, which includes color measurements and their possible graphic presentation. The normal digital images of sporomorphs from several ages and geological settings are used to obtain color measurements in the form of digital Red, Green and Blue triple color system (RGB). These measurements were accomplished using some software programs such as Photoshop™© or ImageJ with employing average microscope setup. The triple RGB color readings are plotted on a ternary diagram, which is divided into three fields. These fields express the maturity levels. The presented new RGB-based quantifying technique is economic and provides a simple examination for maturity, which is linked to the hydrocarbon generation. This can partially replace or walk side by side with the vitrinite reflectance microscopy. 相似文献
208.
随着“数字城市”建设的推进,地理信息系统建设进入全面发展阶段,加快基础空间数据更新频率的需求日趋强烈。如何有效的使用基础空间数据,为城市建设增砖加瓦成为政府部门关注的问题。该文主要阐述某个城市的系统方案设计、体系架构、网络架构与实现功能,为其他三维数字城市管理平台的建设提供一定的参考依据。 相似文献
209.
在被动型氢原子钟数字伺服电路中,使用FPGA对误差信号进行数字信号处理。设计了一种简单的低通滤波器,与传统的FIR滤波器相比,节省了FPGA的使用资源,并且性能优于传统滤波器,能够很好地应用于被动型氢钟。 相似文献
210.