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21.
根据移动地图服务的特点以及SVG的子集MobileSVG在移动设备中应用的优点,首先讨论了传统SVG地图组织模式在移动地图服务中的缺点,在此基础上提出一种新的适合移动地图服务的利用MobileSVG组织地图数据的方式,并对其组织与编码方式进行了详细的说明。  相似文献   
22.
我国目前正处于工业化中期,发展劳动密集型产业对促进就业、提高劳动者收入、发挥潜在经济增长力、实现社会稳定等方面都具有重要的意义。我国目前发展劳动密集型产业符合比较优势,但比较优势并不等于竞争优势。当前我国劳动密集型产业仍然存在附加值低、劳动生产率低、企业自身竞争力弱、贸易磨擦频发、价格贸易条件恶化等一系列问题,严重影响了我国外贸的可持续发展。通过对上述问题的剖析,阐述了劳动密集型产业与技术进步、资本技术密集型产业以及国际贸易之间的关系,认为应该实现劳动密集型产业的比较优势向竞争优势的转换,并从不同的角度提出了政府、企业为实现这种转变应采取的措施。  相似文献   
23.
考虑资源三号卫星轨道、姿态数据和光学传感器内部结构,构建合适的内方位模型和外方位模型描述内方位元素和外方位元素的误差变化,选取合适的平差模型进行自检校区域网平差。实验结果表明正确的平差模型能显著提高资源三号卫星的立体几何定位精度。  相似文献   
24.
LOCATION AND ECONOMIC GROWTH: CASE STUDY IN CHINA   总被引:2,自引:0,他引:2  
This paper explores how location could affect economic growth and it has always been omitted in economic analysis. Geographic factors can affect economic activities. Three mechanisms of location affecting economic growth have been studied: consumption, production and migration. The initial superior location will take such advantages as lower transport costs and lower price level, so it could have higher consumption utility, higher productivity, and attract more human capital, then lead higher growth. Those regions with the superior location will have higher utility due to more product varities and the comparative lower price, and higher wage due to the production technology, and it would attract more individuals with higher human capital to move to this location. It is a kind of agglomeration, meaning the superior location will hold more advantages and higher growth rate, otherwise those locations with poor geographic factor will be even worse. Based on Chinese provincial economic growth experiences of these years, this paper does some empirical analysis by regressing on some variables including the geographic ones. In this paper, the dummy variables and population density are used to measure the location factor. And we find evidences supporting the view that dominant locations such as coastal areas grow faster, on the contrary,middle and western provinces grow slower. Location does affect economic growth.  相似文献   
25.
重点介绍黑龙江省位置服务中心十年建设过程与研究成果,就中心硬件配备、平台建设进行阐述;对位置服务平台的逻辑组成、功能架构、终端产品接入及服务接口情况作详细说明;针对中心在北斗领域的研究应用、多年来探索的服务模式,以及位置服务标准化建设所做工作进行探讨。文末对黑龙江省位置服务中心下一步的新技术研究与产品化、市场化策略予以展望。  相似文献   
26.
This article studies how burglars select a house to burglarize. We draw on the rational choice perspective to investigate how burglars select a target by relying on house-related attributes to optimize a combination of perceived rewards, efforts and risk. It extends current applications of the discrete spatial choice framework to burglary target selection by adopting the house as the spatial unit of analysis and studies burglars' target selection process in a larger and more diverse study area than that of earlier studies. Using data on 650 residential burglaries and on approximately 500,000 residential properties in the Belgian province East Flanders, we consider a discrete spatial choice model of burglary target selection to establish which house-related attributes influence burglars' target selection process. Our findings demonstrate that terraced houses, houses without a garage, houses that have not been outfitted with a central heating and/or air-conditioning system and houses nearby burglars' residences are more likely to be selected. Overall, our analysis suggests that burglars rely on effort-related attributes to distinguish between targets while higher perceived rewards actually decrease the odds of a house being burglarized. Risk-related attributes are unimportant for burglars' target choice.  相似文献   
27.
本文通过对天体测量仪器光子计数模拟资料的处理,比较了13种不同的平滑模型和两种定心算法对最终精度的影响;提出了利用频率域滤波和修正矩方法相结合的最佳处理方法;并对比较结果进行了多方面的讨论。  相似文献   
28.
Racial/ethnic diversity in the United States has increased significantly in recent decades, with minority groups now accounting for almost one-third of the total population. At the same time, growing diversity has spread into rural and non-metropolitan areas. Research suggests that changing diversity in the ‘New South’ has seen growth of non-Black communities. The question, however, is the degree to which increasing diversity equates with increasing intermixing or, alternatively, whether racial/ethnic clusters retain their prominence. This paper examines the geographic manifestations of growing racial/ethnic diversity within intra-urban context, using census-tracts as scale of analysis in the metropolitan statistical area (MSA) of Knoxville in Tennessee. The statistics used for analyzing intra-urban variations include Diversity Score, Theil Entropy Index, and Location Quotient. Tract and Block-group data for White, Black, American Indian, Asian, All Others and Hispanic are used for computing these indices. This paper concludes that diversity has increased during 1990-2000, and has dispersed into suburban counties. However, segregation and clustering for certain minority groups has also increased, in particular African-Americans still remain the most segregated and most clustered community confined to specific geographic locations. This research holds significance as local economic development patterns are very much guided by the geographic variability of human and social capital. Applied research can suggest avenues for growth and can help rebuild local communities. This paper will also contribute to literature focusing on methodological challenges in measuring diversity and its geographic manifestations.  相似文献   
29.
The construction of regional advantage has recently been emphasized by scholars as a new way of increasing firms’ competitiveness in a globalizing and learning economy. This article compares the construction of regional advantage and the development paths of specific industries in two different types of non-metropolitan regions, La Pocatière in Canada and Tromsø in Norway. The authors observe a higher level of industrial dynamism in La Pocatière than in Tromsø. They find four explanations for this variation: (1) a narrower regional innovation system (RIS) in Tromsø; (2) the fact that the target industry in Tromsø (marine biotechnology) is, in general, more difficult to develop outside metropolitan regions than the diverse mechanical engineering industry found in La Pocatière; (3) a biased focus on the development of research-based knowledge and academic spin-offs in Tromsø compared with a more varied set of strategies used in La Pocatière; and (4) La Pocatière's location in proximity to the Quebec metropolitan region.  相似文献   
30.
东亚副热带西风急流位置变化与亚洲夏季风爆发的关系   总被引:1,自引:0,他引:1  
张耀存  况雪源 《湖北气象》2008,27(2):97-103
利用1961~2000年的NCEP/NCAR候平均再分析资料,初步探讨了季节转换期间东亚副热带西风急流南北和东西向位置变化与亚洲季风爆发之间的联系。结果表明,亚洲夏季风爆发伴随着东亚副热带西风急流轴线的北跳和急流中心西移,急流轴北跳至35°N以北的青藏高原上空,南支西风急流消失,亚洲季风环流形势建立。南海季风爆发早年,低纬的东风向北推进的时间早,到达的纬度偏北,中纬的西风急流强度偏弱,季风爆发晚年则相反。同时,南海夏季风爆发早年,青藏高原上空急流核出现较早,西太平洋上空急流核减弱较快,急流中心“西移”较早。而在南海夏季风爆发晚年,西太平洋上空的急流核减弱较迟,青藏高原上空急流核形成偏晚,急流中心“西移”较迟。此外,急流中心东西向位置和强度变化与江淮流域梅雨的开始和结束也有密切关系。  相似文献   
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