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771.
合肥市夏季热岛特征研究   总被引:8,自引:1,他引:8  
根据2002牟夏季高温期间合肥市城市小气候考察的资料,分析了合肥市夏季城市热岛特征以及热岛强度的历史变化。结果表明:1)合肥市夏季热岛强度的日变化与冬季明显不同,夏季晴天一天中热岛强度只出现一个峰值,其基本特征与Oke提出的理想状态下的城市热岛强度日变化的模式曲线非常相似,而冬季与高纬地区的加拿大卡尔加里城市的热岛强度日变化特征接近。这反映了冬、夏两季人类活动、能源消耗量的不同;2)随着城市范围的扩大和城市绿化工程的实施,合肥市热岛面积、分布形状有了一定的改变,但主要分布特征和强度基本没有变化。  相似文献   
772.
青海气候条件对牧草再生性影响的研究   总被引:2,自引:0,他引:2  
祁如英  汪青春  陈芳 《气象》2005,31(5):21-25
选取1994~2001年河南、甘德两站牧草再生草资料及同期气象资料,通过分析同一地区不同时期及同一时期不同地区气候条件对牧草再生性的影响,建立了牧草再生草产量气候模式,讨论了再生草增、减产的气候条件。研究得出:同一地区不同时期和同一时期不同地区因气候条件不同,割草不一定能增产。  相似文献   
773.
房产测绘平面图系统的实现研究   总被引:1,自引:0,他引:1  
陈洋  张宏  蒋文明  乔延春  温永宁 《现代测绘》2005,28(3):15-16,19
随着城市规划管理的不断发展.使得城市房产测绘单位采用大型空间数据库管理测绘平面图资料成为必然。通过建立房产测绘平面图系统,可以有效地解决数据标准不一致.图数不能互访,测绘各部门无法协调一致等问题,充分发挥网络功能,提升整个城市的房产管理水平.达到房产管理和房产服务一体化的目标。本文详细论述了房产测绘平面图系统的概念、设计原则和系统功能.在南京数字房产共享平台的建设中得到了实现.并取得了良好的效果。  相似文献   
774.
方萍  赵卫  陈勇 《现代测绘》2005,28(1):29-30
介绍了利用全球定位系统(GPS)静态定位技术,如何为滆湖公路大桥建立控制网,延伸出时控制网平差方案的确立上,以及如何使控制网中的成果与公路主线控制网中的成果互相兼容,从而为工程的设计与施工提供必要的控制资料。  相似文献   
775.
Present methodological research on geographically weighted regression (GWR) focuses primarily on extensions of the basic GWR model, while ignoring well-established diagnostics tests commonly used in standard global regression analysis. This paper investigates multicollinearity issues surrounding the local GWR coefficients at a single location and the overall correlation between GWR coefficients associated with two different exogenous variables. Results indicate that the local regression coefficients are potentially collinear even if the underlying exogenous variables in the data generating process are uncorrelated. Based on these findings, applied GWR research should practice caution in substantively interpreting the spatial patterns of local GWR coefficients. An empirical disease-mapping example is used to motivate the GWR multicollinearity problem. Controlled experiments are performed to systematically explore coefficient dependency issues in GWR. These experiments specify global models that use eigenvectors from a spatial link matrix as exogenous variables.This study was supported by grant number 1 R1 CA95982-01, Geographic-Based Research in Cancer Control and Epidermiology, from the National Cancer Institute. The author thank the anonymous reviewers and the editor for their helpful comments.  相似文献   
776.
The FORMOSAT-3/COSMIC mission is a microsatellite mission for weather forecast, climate monitoring, and atmospheric, ionospheric and geodesy research. This mission is a collaborative Taiwan-USA science experiment to deploy a constellation of six microsatellites in low Earth orbits. The mission life is 2 years with a goal of 5 years. The final mission orbit has an altitude of 750–800 km. Each satellite consists of three science payloads: global positioning system (GPS) occultation experiment (GOX) payload, tiny ionospheric photometer (TIP) and tri-band beacon (TBB). The GOX will collect the GPS signals for the study on atmosphere, ionosphere, and geodesy. The TIP and TBB can provide the electron distribution information for ionospheric research. The deployment of the FORMOSAT-3 constellation and the resulting influence on the occultation sounding distributions are reported. Details are also given on GOX, TIP, and TBB payload operations and the contributions of the Taiwan Science Team.  相似文献   
777.
Annual amphidromes: a common feature in the ocean?   总被引:1,自引:0,他引:1  
The scientific term "amphidrome" is usually associated with tides in oceanography. The dozen tidal amphidromes observed in the ocean are critical points that determine the fundamental pattern of the global tidal system. Exploration of recently available satellite data with an unprecedented 1-2 decades duration suggests that an amphidrome is not a tide-only phenomenon in the ocean. Analysis of altimeter-derived sea level anomaly (SLA) data and radiometer-derived sea surface temperature (SST) data allows ten amphidromic points to be clearly identified in annual SLA and SST variations. These amphidromes are located in the tropical areas of the Pacific, Atlantic, and Indian oceans. Their existence implies that the annual cycle (in time) of the atmosphere-ocean system is translated into a rotary variation (in space) for many of the geophysical parameters. It can be concluded that annual amphidromes are common, the knowledge of which is of particular interest, given their annually "constant" nature, for the monitoring and understanding of oceanic, climatic, as well as biological variabilities at seasonal to decadal scales, which strongly affect many aspects of the natural and societal activities on the globe.  相似文献   
778.
Geocomputation, Geodemographics and Resource Allocation for Local Policing   总被引:1,自引:0,他引:1  
The field of geodemographics is one of the most fertile applications areas of geocomputation research. Geodemographic profiles of the characteristics of individuals and small areas are pivotal to tactical and strategic resource management in many areas of business, and are becoming similarly central to efficient and effective deployment of resources by public services. In this context, this paper describes research that has been developed in partnership with the Devon and Cornwall Constabulary and Institute of Criminal Justice Studies (ICJS) at the University of Portsmouth to assess the potential use of geodemographics as a policing tool. Crime, the fear of crime and the efficacy of public services are issues that have moved to the top of the UK political agenda and have long been matters of serious public concern. This paper considers the ways in which police forces might use geodemographics to better deploy resources at a variety of spatial scales in England and Wales.  相似文献   
779.
Although cliffs form approximately 75% of the world's coastline, the understanding of the processes through which they evolve remains limited because of a lack of quantitative data on the morphological changes they undergo. In this paper the combination of terrestrial time-of-flight laser scanning with high-resolution digital photogrammetry is examined to generate high-quality data-sets pertaining to the geomorphic processes governing cliff development. The study was undertaken on a section of hard rock cliffs in North Yorkshire, UK, which has been monitored over a 12-month period. High-density, laser-scanned point clouds have been used to produce an accurate representation of these complex surfaces, free from the optical variations that degrade photographic data. These data-sets have been combined with high-resolution photographic monitoring, resampled with the fixed accuracies of the terrestrial laser survey, to generate a new approach to recording the volumetric changes in complex coastal cliffs. This has led to significant improvements in the understanding of the activity patterns of coastal cliffs.  相似文献   
780.
为解决城市边界层中大气O3浓度的预报问题,选用一种简明有效的光化学反应方案建立光化学模式, 并与大气平流扩散的箱格预报模型进行了嵌套,从而将大气化学过程引入到城市空气污染数值预报系统 (CAPPS) 中。同时,根据实际需要研究了VOC (Volatile Organic Compounds) 浓度及NOx源排放量等参数缺测时,根据前期监测浓度采用遗传算法反演未知参数的具体方法。利用2001年9月8~17日在北京舞蹈学院监测的O3、NOx资料及相应的气象数据,用改进后的CAPPS模式进行了单箱预报试验。预报试验结果表明,嵌套后的模式对O3浓度的变化具备一定的预报能力。  相似文献   
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