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1.
The application of composite suitability mapping integrated with a geographic information system is progressing at a much faster rate than the methodological improvements necessary for optimal use in the public planning context. The use of value functions is suggested as an alternative scaling procedure that is scientifically and operationally preferable to existing procedures. Value functions limit the operational subjectivity and enhance the potential for replication and verification of the analysis. Value functions are conducive to increased automation of the land planning and decision process while being comprehensible to non-expert decision-makers and the public.  相似文献   

2.
The application of composite suitability mapping integrated with a geographic information system is progressing at a much faster rate than the methodological improvements necessary for optimal use in the public planning context. The use of value functions is suggested as an alternative scaling procedure that is scientifically and operationally preferable to existing procedures. Value functions limit the operational subjectivity and enhance the potential for replication and verification of the analysis. Value functions are conducive to increased automation of the land planning and decision process while being comprehensible to non-expert decision-makers and the public.  相似文献   

3.
新疆土地详查历经八年,至今未完。为降低劳动强度,提高工作效率,针对叶城县山区土地利用类型多样,耕地分散等特点,进行了微机制图的探讨。本文着重介绍了(1)微机制图的软硬件工作环境;(2)图形编辑和编码技巧;(3)图形量化方法,建立图形库;(4)属性数据输入、更新、修改;(5)错误信息检查,建立点线面的相互关系;(6)面积计算与机助制图。  相似文献   

4.
ABSTRACT. City maps are among the oldest and most popular forms of cartographic representation, yet urban cartography has received only limited scholarly attention. A review of the early history of city mapping suggests a progression of representational forms from profile to perspective to plan, a progression that parallels urban growth. The history of urban mapping reflects a desire to comprehend the geography of the city for reasons of curiosity and practical necessity, but the map also may become an icon that engenders a sense of pride and belonging, if not allegiance and control. An examination of Chicago maps indicates that, in addition to evolution in representational styles, the subjects of maps change to serve demands of the moment. City maps not only constitute a rich historical archive but also are dynamic agents in urban development. The urban landscape is shaped by cartographic vision.  相似文献   

5.
In this article I reexamine Alexander Hamilton Rice's seventh expedition to Amazonia (1924–1925) in order to highlight the ways in which the image of the modern explorer was constructed through various technologies of visualization, including maps, still photography, and film. The Rice expedition was equipped with the latest surveying instruments, among them a hydroplane especially adapted for taking aerial photographs, and it was the first to attempt shortwave radio communication in the Tropics. However, the expedition's efforts to reach the headwaters of the Rio Branco ended in failure. I investigate Rice's heavy investment in making a visual record of the expedition in the context of his academic ambitions. Despite his influence in learned societies in the United States and Europe, his questionable reputation within academic circles was difficult to overcome: His reliance on publicity to enhance his academic career had adverse consequences. The retelling of Rice's tale here also sheds light on the role of indigenous local knowledge and agency in the history of exploration. All the modern surveying technology employed notwithstanding, local support remained crucial for Amazonian exploration.  相似文献   

6.
非连续分布面状地理现象的图形自动概括方法   总被引:8,自引:3,他引:8  
齐清文  刘岳 《地理研究》1996,15(1):1-10
本文首先阐述了图斑概括过程中应遵循的原则,即正确处理几何精确性与地理真实性、清晰性和详细性两对矛盾,继而提出了自动化制图综合的设计策略。然后探讨了非连续分布面状地理现象(即图斑)的自动取舍、化简、夸大和移位、以及合并等算法,介绍了上述算法的实现方法,并给出几种地物图形自动概括的应用技术流程。  相似文献   

7.
基于栅格数字高程模型提取特征地貌技术研究   总被引:71,自引:0,他引:71  
闾国年  钱亚东 《地理学报》1998,53(6):562-570
本文对近年来基于栅格数字高程模型提取特征地貌技术进行了详细的研究,认为该技术的关键在于两个方面:一是如何定义地貌形态结构,二是提取算法的设计。本文提出了基于地貌学角度来定义地貌形态结构的方法,利用有限个数的形态要素的空间组合和对比分析来获取特征地貌,并可以对各种特征地貌形态进行符合物理意义的改进。  相似文献   

8.
9.
Historical first‐generation frontier roads in America's trans‐Appalachian West often evolved from buffalo and Indian trails into pioneer routeways such as Daniel Boone's Trace and, eventually, into twentieth‐century hard‐surface highways. Period cartographers found these routes difficult to document accurately, and present‐day scholars often depict them only on small‐scale maps, which simply illustrate connections between origin and destination points. Accurately mapping Kentucky's first‐generation roads at large scale requires detailed site and contextual topographic information over long distances, but historical maps, diaries, surveyors' reports, and other period documents often lack sufficient detail for route‐related sites to support mapping. Use of gis software enables positioning historical routes onto U.S. Geological Survey contour‐ and hill‐shaded base maps by mapping verifiable locations and linking them through interpretation of best‐choice routes that consider frontier migrants' transportation priorities, such as direction, distance, gradient, and land‐surface character.  相似文献   

10.
基于栅格数字高程模型自动提取黄土地貌沟沿线技术研究   总被引:34,自引:2,他引:34  
闾国年  钱亚东 《地理科学》1998,18(6):567-573
从数字高程模型中提取具有精确定位特征的连续的沟沿线是构建黄土沟壑丘陵地区土壤侵蚀,泥沙搬运和径流过程的空间分布式机理-过程模型的关键技术。本文提出了基于地貌形态学特征的地貌提取技术,在提取具有代表性的黄土丘陵沟壑区山西离石王家沟流域汇流网络的基础上,自动提取了该流域完整的沟沿线,得到了满意的结果。  相似文献   

11.
ABSTRACT. When drawing and painting were the only ways to create visual documentation of new discoveries, artists played a central role in geographical exploration. The legacy of expeditionary art offers opportunities for building stronger linkages between art and geography. A framework is laid out for classifying expeditionary art, describing how it can be appraised as pictorial information. The work of two artists of the nineteenth century, Richard Kern and Frederick Catherwood, exemplifies key aspects of expeditionary art.  相似文献   

12.
Access to the sun for space heating of structures is controlled, in part, by topographic shadowing in high-relief regions. A simple graphic procedure is presented for mapping shadows on topographic maps for any date and time of day. Comparisons of computed shadows and shadows measured from aerial photography confirm that the mapping procedure is reliable and accurate. Use of the procedure as a solar access inventory tool is illustrated in an area of the Green Mountains, VT.  相似文献   

13.
本文叙述了面状符号系统软件的结构特点,阐明了面状符号软件设计的逻辑思路和算法原理,指出了符号软件在专题自动制图中应用的广阔前景。  相似文献   

14.
ABSTRACT. Landscape diversity has increased with the surprising postfire establishment of aspen at upper elevations (700–945 meters above sea level) in the High Peaks of Adirondack Park in upstate New York. Tree seedlings returned quickly to the charred slopes west of Noonmark Mountain after an accidental fire consumed the forest in 1999. Aspen stands have replaced the spruce‐fir‐birch forests in the burned area even though mountain paper birch is expected to colonize burned sites at these elevations. Environmental conditions, historical events, and unique circumstances help explain why quaking aspen and bigtooth aspen rather than paper birch blanket the burned mountainside. Climate change over the past century to warmer, wetter conditions may have fostered this marked shift in species composition. In the unburned firebreak that people cleared to contain the flames, pin cherry has regenerated from seeds stored in the soil for nearly a century. The history of pin cherry on the site suggests that large fires or severe windthrow may have been more common in the region than was previously documented.  相似文献   

15.
鄂栋臣  张胜觊 《极地研究》2011,23(3):226-231
首先绘出常用的几种坐标系,包括空间直角坐标系、大地坐标系、站心坐标系及平面坐标系的定义,然后举例介绍几种常用的大地架标系统,如WGS72和WGS84,及国际地球参考框架ITRF2000和ITRF2005.简要回顾国际南极大地坐标系统的发展,重点论述中国南极地区大地坐标系统的建立及发展过程.最后,讨论不同坐标系统之间的转...  相似文献   

16.
Most existing work on residential mobility has assumed that the household relocation decision is an intrinsically significant object of inquiry. In contrast, we argue that mobility derives its significance primarily from the particular historical and locational contexts within which it occurs. We suggest, therefore, that future mobility research should be directed away from the development of a theory of mobility per se and toward a more explicit articulation of mobility studies to existing theories of urbanization and social change.  相似文献   

17.

The freestanding ambulatory surgery center (FASC), also known as an outpatient or day surgery center, is one of several modern health care providers which are currently challenging the dominance of traditional medical professionals. This paper examines the location and distribution of FASCs in the United States for the period 1987–1992. FASCs tend to be concentrated in the states of the South and West, and have exhibited increasing concentration in these regions during the five-year study period. In addition, FASCs are found mostly in metropolitan areas and appear to be moving toward more suburban locations, although central city sites still dominate. Future research should concentrate on more micro-scale locations of the FASC and other nontraditional health care providers.  相似文献   

18.
19.
黄河上中游产水产沙系统与下游河道沉积系统的耦合关系   总被引:33,自引:4,他引:33  
许炯心 《地理学报》1997,52(5):421-429
本文在黄河为例,动用数理统计方法,研究了河流流域系统中产水产沙子系统与河道沉积子系统之间的关系,得到了描述这种耦合关系的多元回归模型。运用这一模型,可以定量回答来自上中游不同来源区的泥沙,各有多大比例淤在下游河道中的问题。  相似文献   

20.
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