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351.
1978-2015年东莞豪华酒店时空演变与制度重构   总被引:1,自引:1,他引:0  
蔡晓梅  刘美新 《地理学报》2016,71(8):1436-1455
东莞豪华酒店作为社会文化地理现象备受学术界与理论界的关注。本文采用深度访谈和文本分析方法,援引制度与空间的相关理论,探讨东莞豪华酒店时空演变背后的制度根源,试图解释在国家与地方的制度环境下,显性正式与非正式制度、隐性正式与非正式制度是如何成为一种内在的力量影响东莞豪华酒店的时空演变。研究发现:① 在地方尺度下,东莞豪华酒店经历了酝酿期(1978-1993年)、投资和投机探索期(1994-1999年)、腾飞发展和扭曲变异糅合期(2000-2004年)3个阶段,分别呈现出制度推动空间发展、制度与空间磨合、空间反作用于制度重构3个不同的特征;② 在区域尺度下,东莞豪华酒店迎来平行和稳步建构期(2005-2012年),体现出权力空间从东莞流向外围。空间变化暗示权力关系的变化,表明东莞豪华酒店从深层次影响制度重构已经迫在眉睫;③ 在国家尺度下,东莞豪华酒店进入自上而下的整顿和转型重构期(2013-2015年),显性正式制度迫使空间行为选择进入理性阶段。研究完善了制度与空间关系的理论,提出空间的发展最终受制于显性正式制度,中间经历了空间尺度的转换,经历了各种显性与隐性、正式与非正式制度的博弈,最终回归到显性正式制度。空间演变是一个被制度化的过程,制度在空间权力关系中不断完善与变迁才能形成符合空间景观与空间形态规律的制度体系。  相似文献   
352.
通过对潘谢矿区几起典型出水事故案例的分析,总结出工作面顶板砂岩出水具有出水时间短,水量迅速增大,储量以静储量为主等特点,分析了影响顶板砂岩涌水的主要因素(砂岩的发育厚度、埋藏深度、地质构造的影响、地下水对其补给的条件、煤层采动对覆岩的破坏程度、工作面的推进速度、钻孔的封闭质量等),并提出防治煤层顶板砂岩水害的综合措施.  相似文献   
353.
This paper takes Zhexi hydraulic region in Taihu Basin as a study area. On the basis of hydraulic analysis function of Arcgis8.3, the drainages were delineated by selecting the monitoring points and discharge stations as outlets. The landuse map were finished by denoting the TM/ETM image. The precipitation map was finished by spatial interpolation according to the rainfall monitoring records. Overlaying the drainage boundary, landuse map and precipitation map, the rainfall, different landuse type area, and runoff pollution concentration and runoff were calculated. Based on these data in different sub-watersheds, by Origin7.0 regression tool, an equation is established to predict runoff using the relationships between runoff, precipitation depth and land use patterns in each of the sub-watersheds. Selecting the sub-watershed which is mainly composed of forest landuse type, the mean runoff concentration (MRC) from sub-watershed has been estimated. The mean runoff concentration of farmland has been estimated by the same methods after the contribution of forest landuse type was removed. The results are: for the forest landuse type, the mean runoff concentrations of COD, BOD, Total N and Total P are 2.95 mg/l, 1.080 mg/l, 0.715 mg/l, and 0.039 mg/l, respectively; for the farmland, the mean runoff concentrations of COD, BOD, Total N and Total P are 5.721 mg/l, 3.097 mg/l, 2.092 mg/l, and 0.166 mg/l, respectively. By using these results, the agriculture non-point pollution loads have been assessed. The loads of COD, BOD, Total N and Total P in Zhexi region are 14,631.69 t/a, 6401.93 t/a, 4281.753 t/a and 287.67 t/a, respectively.  相似文献   
354.
广西大厂锡多金属矿床硅质岩和层状矿体氧硅同位素研究   总被引:1,自引:0,他引:1  
姚晓梅  丁悌平 《地球学报》1994,15(Z1):124-130
作者对大厂地区泥盆纪地层中的不同成历的硅质岩进行了系统的硅氧同位素研究。其中一种是与矿化无关的浅海放射虫硅质岩,其硅质来自海水的溶解硅,表现出低的负δ30Si值和变化较大的δ18O值;另一种岩石可能属海底喷气成因,表现出你的负δ30Si值和均一的δ18O值,与硫化物成矿作用有密切关系。  相似文献   
355.
利用常规气象观测资料、NCEP/NCAR再分析资料和多普勒天气雷达资料,对2016年8月6—8日潍坊一次强对流天气的成因和预报误差进行了分析,结果表明:1)500 hPa冷涡底部低槽、850 hPa低涡切变线和地面倒槽是主要影响天气系统, 数值预报对此次天气过程的影响系统预报偏差大,而预报员对数值预报依赖程度高是此次预报失误的主要原因;2)850 hPa以下强的水汽辐合是强降水发生的重要条件,低层辐合和高层辐散配置导致的强垂直上升运动是暴雨产生的动力机制,位势不稳定因中高层的冷空气入侵下沉得以加强;3)列车效应和强回波维持少动是造成短时强降水的重要回波特征,逆风区的发展和移动对于判断强降水的落区有指示作用,多普勒雷达反演风场中的中尺度辐合线是导致局地强降水发生的直接原因;4)风廓线雷达水平风场可以连续地反映降水过程中风场垂直结构及其变化,降水发生前探测高度明显升高,中高层冷空气侵入时间与强降水的时段相对应。  相似文献   
356.
利用鲁中地区2001—2016年伴随瞬时风力不低于8级的所有强对流天气个例共106次进行分析,总结其气候特征,并通过箱须图的形式研究了分类强对流天气相关环境参数的分布特征和预报阈值。结果表明:2001—2016年强对流天气分布呈山区多、平原少、中部多、北部和西南部少的特点;6月和6月中旬是主要月份和旬份;地面辐合线是最主要触发机制类型;雷暴大风型、冰雹雷暴大风型和强降水混合型对应的地面和850 hPa的平均温度露点差,0~1 km和0~3 km垂直风切变,SWEAT指数、LI指数、K指数、风暴相对螺旋度、高度指数等环境参数各有不同的最低阈值;鲁中地区易发生强对流天气的0 ℃层高度为4.1 km左右;对于伴随冰雹的强对流天气,其融化层高度比0 ℃层高度低0.6 km左右。根据以上环境参数的分布特征、高低空垂直风切变的强弱变化可对3类强对流天气进行一定程度的区分。  相似文献   
357.
The change of sea surface temperature(SST) in the southern Indian Ocean(SIO) during the recent six decades has been analyzed based on oceanic reanalysis and model, as well as atmospheric data. The results show that a thermal regime shift in SIO during the 1960 s, which is not caught enough attentions, has been of equal magnitude to the linear warming since 1970. Empirical Orthogonal Function(EOF) analyses reveal that a thermal shift is combined with atmospheric changes such as the weakening of westerly during the period of 1960–1967. Inner dynamic connections can be defined that when the westerly winds turn weak, the anticyclonic wind circulation between westerly winds and the trade winds decreases, which further reduces the SST to a negative peak in this period. It is noted that the shifts in the 1960 s are also evident for Southern Hemisphere. For example, subtropical high and the entire westerly winds belt at high latitudes both change dramatically in the 1960 s. This large-scaled process maybe link to the change of southern annular mode(SAM).  相似文献   
358.
在地震资料采集时,受地表条件、震源等因素的影响,几乎无法采集到近偏移距数据,不利于后续数据的处理。针对这一问题,研究了一种利用多次波和二维匹配滤波的近偏移距数据重构方法。首先给出了由表层多次波构建准一次波的互相关方法;然后在时间-空间滑动窗口内利用准一次波计算二维匹配滤波器,并用该滤波器重构近偏移距数据;最后使用均方根振幅校正方法校正重构数据的振幅。整个数据重构的过程在频率域进行,避免了基于维纳滤波方法求取滤波器的大量计算;同时使用快速傅里叶变换算法,提高了计算效率。与一维匹配滤波的近偏移距重构方法相比,采用二维匹配滤波方法的重构数据在空间上连续性更好。通过对Sigsbee 2B数据的处理及实际资料的测试,验证了该方法的正确性和有效性。  相似文献   
359.
A group of statistical algorithms are proposed for the inversion of the three major components of Case-Ⅱ waters in the coastal area of the Huanghai Sea and the East China Sea. The algorithms are based on the in situ data collected in the spring of 2003 with strict quality assurance according to NASA ocean bio-optic protocols. These algorithms are the first ones with quantitative confidence that can be applied for the area. The average relative error of the inversed and in situ measured components‘ concentrations are: Chl-a about 37%, total suspended matter (TSM) about 25%, respectively. This preliminary result is quite satisfactory for Case-Ⅱ waters, although some aspects in the model need further study. The sensitivity of the input error of 5% to remote sensing reflectance (Rrs) is also analyzed and it shows the algorithms are quite stable. The algorithms show a large difference with Tassan‘s local SeaWiFS algorithms for different waters, except for the Chl-a algorithm.  相似文献   
360.
A large number of primary oil and gas reservoirs have been discovered in Proterozoic strata all over the globe.Proterozoic sequences are widely distributed in China, and the discovery of large Sinian-aged gas reservoirs in the Sichuan Basin and Mesoproterozoic liquid oil seepages in North China shows that attention should be paid to the exploration potential of Proterozoic strata. In this paper, the main controlling factors of Proterozoic source rocks are discussed. Principally, active atmospheric circulation and astronomical cycles may have driven intense upwelling and runoff to provide nutrients; oxygenated oceanic surface waters could have provided suitable environments for the organisms to thrive; volcanic activity and terrestrial weathering caused by continental break-up would have injected large amounts of nutrients into the ocean, leading to persistent blooms of marine organisms; and extensive anoxic deep waters may have created ideal conditions for the preservation of organic matter. Additionally, the appearance of eukaryotes resulted in diversified hydrocarbon parent material, which effectively improved the generation potential for oil and gas. Through the comparison of Formations across different cratons, seven sets of Proterozoic organic-rich source rocks have been recognized in China, which mainly developed during interglacial periods and are also comparable worldwide. The Hongshuizhuang and Xiamaling Formations in North China have already been identified previously as Mesoproterozoic source rocks. The early Proterozoic Changchengian System is highly promising as a potential source rock in the Ordos Basin. In the Upper Yangtze area, the Neoproterozoic Datangpo and Doushantuo Formations are extensively distributed, and represent the major source rocks for Sinian gas reservoirs in the Sichuan Basin. Moreover, the Nanhuan System may contain abundant shales with high organic matter contents in the Tarim Basin, although this possibility still needs to be verified. Indeed, all three cratons may contain source rocks of Proterozoic strata; thus, these strata represent major exploration targets worthy of great attention.  相似文献   
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