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991.
给出了川- 20 地下水综合观测井井下仪器探头可能存在机械部分相互干扰的现场研究结果。所得结果对于正确区分各种手段今后的异常与干扰具有参考意义。  相似文献   
992.
崔俊山 《海岸工程》1999,18(4):74-80
从人们交换农业、手工业产品的“市”到店铺林立的商业一条街,商业和商业建筑的发展与社会和经济的发展密不可分,现代商业建筑的发展更与人们生活和消费水平分不开。因此,必须研究人们的职业与消费习惯、消费心理、做好市场调查和预测,把握市场机遇,创造适合经济和社会发展各阶段的商业间环境,研究国外现代商业建筑的发展,借鉴其经验,使我国商业建筑沿着正确的道路发展。  相似文献   
993.
安徽省地震宏观异常日报集成系统是由Android的App、MySQL数据库和PHP网站组合而成的应用管理系统。从设计思路、框架及主要技术实现出发,介绍集成系统的应用成效。  相似文献   
994.
There exist different response characteristics in the resistivity measurements of dual laterolog (DLL) and logging while drilling (LWD) electromagnetic wave propagation logging in highly deviated and horizontal wells due to the difference in their measuring principles. In this study, we first use the integral equation method simulated the response characteristics of LWD resistivity and use the three dimensional finite element method (3D-FEM) simulated the response characteristics of DLL resistivity in horizontal wells, and then analyzed the response differences between the DLL and LWD resistivity. The comparative analysis indicated that the response differences may be caused by different factors such as differences in the angle of instrument inclination, anisotropy, formation interface, and mud intrusion. In the interface, the curves of the LWD resistivity become sharp with increases in the deviation while those of the DLL resistivity gradually become smooth. Both curves are affected by the anisotropy although the effect on DLL resistivity is lower than the LWD resistivity. These differences aid in providing a reasonable explanation in the horizontal well. However, this can also simultaneously lead to false results. At the end of the study, we explain the effects of the differences in the interpretation of the horizontal well based on the results and actual data analysis.  相似文献   
995.
The Ediacaran Doushantuo Formation with well-preserved fossil record in South China provides a rare window for our understanding of biological evolution,global carbon cycle,and oceanic redox states.Prominent negativeδ~(13)C anomalies(i.e.,the Shuram excursion)in Ediacaran successions worldwide fundamentally challenge the traditional models of isotopic mass balance.Additionally,conflicting opinions of both oxic and anoxic conditions have been proposed for the deep waters during this period.Here,we present a detailed study of pyrite morphology and carbonate carbon isotope data documented from drill core samples at Songtao County,northeastern Guizhou.Framboid aggregates are the dominant pyrite form in black shale and they can transfer to euhedral crystals through continuous growth of the constituent microcrystals.A positive correlation between microcrystal sizes(d)and framboid diameters(D)is observed,while the different D/d ratios of framboids in argillaceous dolostone and black shale reflect different substrate availability.Electron microprobe analyses reveal no consistent compositional patterns between framboidal and euhedral pyrites.Framboid size distributions of the investigated drill core,in combination with previously published redox data from the intra-shelf Jiulongwan section,shelf margin Zhongling section,and lower slope Wuhe section,suggest that three episodes of marine euxinia have been established throughout the deposition of the Doushantuo Formation.The time lag between the uppermost euxinic interval and the Shuram excursion may arise from the depression of sulfate reduction maintained by other oxidants.  相似文献   
996.
This paper presents the changes of crust thickness and Poissons ratios distribution in the Binchuan region,where the first air-gun transmitting station and its a small dense array were deployed.From September 2011 to January 2014,more than 239 teleseismic events of M≥6.0 were recorded in 16 stations in the Binchuan region.Their P-wave receiver functions were analyzed respectively.The high spatial resolution result shows that the average crust thickness of Binchuan region is 45.3km,it follows the rule of"deeper in the north and east part,shallower in the south and west part."The deepest region is in Xiaoyindian Station;the crust thickness is 47.9km;the shallowest region is in Paiying Station,it has the thickness of 42.1km.It shows that the deeper Moho surface nearby the Chenghai fault and shallower nearby the Honghe fault;the isoline distribution of thickness changes greatly nearby the Chenghai fault and slowly nearby the Honghe fault.From the distribution of Poissons ratios,it is unevenly in the study area with a great difference from the north part to the south part,which shows a characteristic of"lower in the north,higher in the south".The Poissons ratio nearby the Honghe fault is medium too high(0.26≤σ≤0.29);lower nearby the Chenghai fault(σ≤0.26).This paper concludes the possible reason of different characteristic between Poissons ratio and crust thickness is thicker in the upper crust in the Binchuan region.  相似文献   
997.
The time-lag effects of droughts on vegetation responses vary significantly across a large-scale river basin. The spatio-temporal response characteristics obtained are important for decision making processes on the allocation and transportation of regional water resources in mitigating drought impacts. Here we consider the Xijiang (West River) basin in South China as a case study, which has experienced severe drought events since the beginning of the 21st century. A threshold level approach is employed to identify the major drought events over the basin in the first decade of this century. The vegetation responses to land soil water evolution are examined, particularly for the severe drought events occurred. The time-lag effects of the vegetation responses within the basin range within 0–96 days. The lower reaches of the headwater sub-basins in the west part of the Xijiang basin are identified as the regions with short time-lag effects. The enhanced vegetation index (EVI) shows consistent responses to the soil water evolution in conjunction with the climate aridity in this area, which is the drought-vulnerable area in the Xijiang basin.  相似文献   
998.
A three‐dimensional transmitting boundary is formulated in the Cartesian co‐ordinate system. It is developed for the dynamic soil–structure interaction problems of arbitrary shape foundations in laterally heterogeneous strata overlying rigid bedrock. Dynamics of a rectangular rigid surface foundation on a homogeneous stratum is analysed by a hybrid approach in which the finite region including foundation is modelled by the conventional finite element method and the surrounding infinite region by the newly developed transmitting boundary. To demonstrate its strength, the present method is applied to a rectangular foundation in a horizontally heterogeneous ground consisting of two distinct regions divided by and welded along a vertical plane. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
999.
基于kernel城镇集聚区密度的计算方法,借助于ArcGIS软件的计算和空间分析功能,分析河南省城镇密集区的历史演变和空间变化,进一步探讨河南省城镇密集区和中原城市群的关系。  相似文献   
1000.
基于GIS的甘肃省区域经济时空差异研究   总被引:2,自引:0,他引:2  
王世杰  赵军 《测绘科学》2010,35(2):170-172
区域经济差异研究一直是区域经济学、发展经济学研究的核心问题之一,也是世界各国经济发展过程中的一个普遍性问题。一直受到各国学术界和政府决策部门的普遍关注。地处中国西北地区的甘肃省,经济社会发展较为落后,省内区域经济差异问题突出。深入分析甘肃省区域经济差异演变规律及其原因对于探索落后地区经济协调发展道路具有重要的理论和实践意义。本文在总结前人研究成果的基础上,采用一系列定量测度指标,运用GIS和空间统计分析方法,研究了2000-2006年间甘肃省区域经济差异及其演变规律。基于ESDA全局和局部空间自相关分析,在GIS软件和GeoDA空间统计软件的支持下,利用甘肃省2000-2006年各市、州和县域人均GDP数据,对甘肃省县域经济的总体和局部空间差异进行了实证分析。  相似文献   
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