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1.
Abstract

This paper covers the development of a GIS instructional module centered on the reintroduction of the Mexican Gray Wolf in the Southwest, United States. This module is used in an undergraduate geography course on the United States. The paper also reports on how forty‐one students applied the module in trying to find an appropriate location to reintroduce the wolf.  相似文献   

2.
Estimates of solar radiation distribution in urban areas are often limited by the complexity of urban environments. These limitations arise from spatial structures such as buildings and trees that affect spatial and temporal distributions of solar fluxes over urban surfaces. The traditional solar radiation models implemented in GIS can address this problem only partially. They can be adequately used only for 2‐D surfaces such as terrain and rooftops. However, vertical surfaces, such as facades, require a 3‐D approach. This study presents a new 3‐D solar radiation model for urban areas represented by 3‐D city models. The v.sun module implemented in GRASS GIS is based on the existing solar radiation methodology used in the topographic r.sun model with a new capability to process 3‐D vector data representing complex urban environments. The calculation procedure is based on the combined vector‐voxel approach segmenting the 3‐D vector objects to smaller polygon elements according to a voxel data structure of the volume region. The shadowing effects of surrounding objects are considered using a unique shadowing algorithm. The proposed model has been applied to the sample urban area with results showing strong spatial and temporal variations of solar radiation flows over complex urban surfaces.  相似文献   

3.
Abstract

Results of a survey to find out whether the GIS program in the Department of Geography at Southwest Texas Stare University (SWT) has served its graduates well are presented. In recent years, a considerable amount of effort has been given to the development of strategies for expanding the existing horizon of GIS education, integrating existing programs, and improving the ways in which GIS education is delivered. This study takes a different approach and seeks to get input from geography graduates who have secured a job in the real world for improving a university GIS program. Based on 26 responses to the survey, employment categories of SWT geography graduates are examined first. Then, geography courses that are considered most helpful in career development by the survey participants are identified. Third, useful GIS courses and essential skills required by the marketplace in the real world as suggested by the survey participants are discussed. It is clear from the results of the survey that the geography program at SWT in general has served its graduates well. Results from the survey also clearly indicate that GIS skills are useful in the career development of most geography graduates, particularly for those who have a concentration area in either GIS/Cartography, Resource and Environmental Studies, or Urban and Regional Planning.  相似文献   

4.
ABSTRACT

The cartographic identification and characterization of urban settlements is problematic, particularly in varied areas or in large geographical extensions. This is due to the divergence between morphological area structures and data attribution, which is generally available at the level of administrative units. Most existing experiences focus on small regions or use indirect data, from which only indirect information can be derived. This paper proposes an identification of urban settlements in the European Union space, which combines urban population and shape through geographic information system (GIS) techniques. For that purpose, 1 km2 cells with associated population data are used. A procedure is developed establishing three different types of urban settlements, according to population and population density values: high-density urban clusters, small and medium-sized towns, and very small towns. A validation of this procedure is performed using direct survey from local experts in 10 selected study areas. The final results show that 78,307 urban settlements can be identified: 88.17% of them are classified as “very small towns,” 10.75% as “small and medium-sized towns,” and 1.08% as high-density urban clusters. This exercise generates new information for the European Union and surrounding countries, and yields the basis for further research. All GIS operations are performed using vector layers, which is not usual in large-area regional studies.  相似文献   

5.
Abstract

Navigation around urban areas is often constraining for the mobility-impaired due to the fabric of the urban landscape, and there is a need to provide maps tailored to individual abilities. Barriers to effective navigation, such as slope, surface type and dropped kerbs, differ for able-bodied pedestrians and wheelchair users. This study identifies and quantifies such differences, and develops a Geographical Information Systems (GIS) network model for the creation of accessibility maps for wheelchair users. The measurement of barriers uses Digital Elevation Models, calculation of rolling resistance, and surveys in the field using hand-held GIS. A spatial database has been constructed which contains the pedestrian route network and barriers to navigation. A GIS application runs the model, providing a user-friendly interface to define and calculate routes through the pedestrian route network that take account of impedances to accessibility. The model, application and interface has been tested with wheelchair users and the route selection provides a good correspondence with patterns of route finding already established through experience. The interface and individually tailored maps generated, provide a tool suitable to assist wheelchair users new to an area; to enable better navigation for existing users, and a means for planners to consider the way in which access is restricted for wheelchair users in their designs for more inclusive urban environments.  相似文献   

6.
从操作对象、数据管理、分析模型、系统功能、GIS应用等五方面对地理信息系统所具有的或所表现出的地理学特性作了初步的探讨,认为:地理学是GIS的理论依托,地理学特性、地理区域分析方法、地理思维方式渗透在GIS的整个工作流程中,成为GIS区别于其他信息系统的本质特征,而计算机等相关技术作为实现GIS功能的技术支持。不应该成为GIS的理论根本。GIS是地理科学体系的重要组成部分,是现代地理研究的重要手段和工具,具有显著的地理性,GIS专业学生应当重视地理学理论的学习。  相似文献   

7.
Abstract

Urban integration is an increasingly popular phenomenon. It is important to characterize the dynamic processes of urban integration from the perspective of geography. However, previous studies mainly focussed on the overall characteristics of a single entity and failed to consider inter-city influences. Therefore, this study aims to systematically investigate this phenomenon. Firstly, spatial clustering technique and landscape metric were used to analyze the temporal change of spatial layout. Secondly, we built multiple ring buffers of city boundary to reveal the directional differences in urban expansion. Lastly, we compared the observed land use data with the results simulated by cellular automata model. These experiments have shown that the urban expansion characteristics during the urban integration process are rather different from those of a single city, and the above methodology can effectively characterize the urban integration phenomenon. The successful example of Guangzhou–Foshan integration could also provide practical experience for other similar attempts.  相似文献   

8.
The role of GIS in Digital Earth education   总被引:2,自引:0,他引:2  
Abstract

A growing number of educators worldwide have become convinced that geotechnologies – including geographic information systems (GIS), global positioning systems (GPS), and remote sensing – are key technologies to prepare students to be tomorrow's decision makers. Grappling with local, regional, and global issues of the 21st century requires people who think spatially and who can use geotechnologies. Some educators teach geotechnologies as a discipline, emphasising skills. Other educators use geotechnologies as a tool to teach content, such as geography, history, environmental studies, Earth Science, biology, mathematics, economics and other disciplines. Issues such as traffic, population growth, urban sprawl, energy, water, crime, human health, biodiversity and sustainable agriculture are growing in complexity, exist at every scale and increasingly affect people's everyday lives. Each of these issues has a spatial component. Drivers for geotechnology education include educational content standards, constructivism, the school-to-career movement, active learning, citizenship education, authentic practice and assessment, interdisciplinary education, community connections and a sustained, increasing demand for GIS professionals. Digital Earth is an ideal framework for contextualising domains of inquiry. The Digital Earth community can have a significant impact on the growth of geotechnologies in education, and conversely, the growth of geotechnologies in education and society can foster the forward movement of Earth systems concepts.  相似文献   

9.
GIS技术在杭州市江干区规划编制中的应用研究   总被引:1,自引:0,他引:1  
在城市规划编制工作中,充分利用GIS技术充实规划的空间内涵,强化规划的空间指导和约束功能,是树立和落实科学的发展观、促进区域经济社会的协调发展的必然要求。首先对传统规划方法的不足进行了总结,接着以杭州市江干区经济地理信息系统辅助江干区“十一五”规划编制的建设为例,说明了GIS技术在规划编制中的应用,最后总结了GIS技术在提高规划的科学性和有效性方面广阔的应用前景。  相似文献   

10.
Abstract

Landsat Thematic Mapper (TM) data have been used to monitor land cover types and to estimate biophysical parameters. However, studies examining the spatial relationships between land cover change and biophysical parameters are generally lacking. With the integration of remote sensing and Geographic Information Systems (GIS), these relationships can be better explored. The research reported in this paper applies this integrated approach for detecting urban growth and assessing its impact on vegetative greenness in the Zhujiang Delta, China. Multi‐temporal Landsat TM data were utilized to map urban growth and to extract and identify changes in vegetative greenness. GIS analyses were conducted to examine the changing spatial patterns of urban growth and greenness change. Statistical analyses were then used to examine the impact of urban growth on vegetative greenness. The results revealed that there was a notably uneven urban growth pattern in the delta, and urban development had reduced the scaled Normalized Difference Vegetation Index (NDVI) value by 30% in the urbanized area.  相似文献   

11.
基于GIS的呼和浩特市区街道信息变迁分析   总被引:1,自引:0,他引:1  
基于人文地理学、城市地理学理论,运用历史文献和统计分析方法,运用GIS,并参阅呼和浩特市地名志、呼和浩特市新城区志等资料,对近百年来的呼和浩特市街道信息变迁进行分析。研究结果表明,近百年呼和浩特市街道数量明显增多;新建街道主要向东南方向扩展;街道名称的变化反映了不同时期的社会背景。  相似文献   

12.
Abstract

A decline in water quality in the Okatie River, a coastal estuary located in Beaufort County, SC, has resulted in the closure of several shellfish beds. Continuing urban development within the watershed has altered land cover conditions and may be contributing to the recent decline in water quality. Remote sensing and geographic information system (GIS) technology, coupled with a water quality model were used to spatially model stormwater runoff to understand the relationship between recent changes in land cover and watershed runoff characteristics. High spatial resolution imagery acquired in 1994 and 1996 spatially documented pre‐ and post‐development land cover conditions within the watershed. The water quality model Agricultural Nonpoint Source Pollution (AGNPS) evaluated land characteristics such as soil type, topography, and land cover to simulate surface water flow and sediment transport over past and current land cover conditions. Results of the model were used to locate net increases of fresh water discharge and to suggest best management practices (BMP).  相似文献   

13.
基于GIS的城市内涝灾害分析模型研究   总被引:9,自引:0,他引:9  
根据气象、水文、水利等专业知识,利用GIS的空间分析技术,结合城市地理数据库和数学计算模型及城市暴雨强度经验公式,建立城市内涝灾害分析模型。该模型是城市内涝积水计算和模拟的基础,能够根据城市降雨分布情况,模拟和预测城市的内涝灾害有关特征数据,如内涝积水的空间分布、深度分布、淹没面积和淹没时间等,模拟结果可为防灾减灾部门制定防灾减灾措施提供依据。  相似文献   

14.
如何实现GIS网络数据在Oracle中的存储、管理、应用与开发是GIS的一个重要研究内容。基于Oracle10g SDO网络实现GIS网络数据的存储与管理,不需要人为设计存储方案,并利用MapViewer完全支持SDO网络的特点,快速实现GIS网络的Web GIS开发,为建立与开发更为复杂的GIS网络系统提供基础支持和保障。  相似文献   

15.
城市化研究的GIS方法   总被引:4,自引:1,他引:3  
城市化作为现代化进程中的一个普遍现象,历来为研究者所重视。城市化的研究方法处于不断丰富和发展的过程中。本文结合地理信息系统的可视化技术、空间分析功能、地理信息系统建模方法,根据中国城市化特点提出了城镇人口比与城镇人口绝对规模相结合的城市化水平测度模型,在人口地理信息系统集成该模型,将中国城市进行了城市化测度分级;在总结现有研究成果的基础上提出以距离为选择要素,多指标综合的城市群分析模型,在人口地理信息系统中为分析城市化进程中的城市群现象提供了一种灵活工具。  相似文献   

16.
ABSTRACT

The aim of this paper is to create and present a new archaeological predictive model via GIS, incorporating what archaeologists consider the most important criterion absent of similar past models, that of critical thinking. The new model suggested in this paper is named habitation Model Trend Calculation (MTC) and is not only integrates the archaeological questions with a critical view, but it can be easily adjusted, according to the conditions or the questions concerning the archaeological community. Furthermore, it uses new topographical and geomorphological indexes such as Topographical Index (TPI), Hillslope and Landform Classification that give a new sense of the topographical and geomorphological characteristics of the examined area; therefore this model is a more powerful tool compared to older models that did not use new topographical and geomorphological indexes. The success of the created model is checked as a case study in the region of Messenia, Greece during the Mycenaean era. The region of Messenia is considered as one of the most important Mycenaean regions of Greece due to the great number and the importance of Mycenaean sites identified. For the present paper, 140 habitation sites were divided into four hierarchical categories (centers, large villages, villages, and farms) based on the extent and the plurality of the tholos tombs that exist in the broader region and according to the hierarchical categorization used by the archaeologists who have studied the area. The new predictive model presented in this work can assist in solving a series of criticisms that have been expressed in the previous studies regarding such models. Additionally, in the case of Mycenaean Messenia, the model shows excellent results in relation to the habitats of the time.  相似文献   

17.
元胞自动机城市增长模型的空间尺度特征分析   总被引:4,自引:2,他引:2  
基于元胞自动机模拟城市系统的复杂行为时,空间尺度是一个非常重要的概念,模型的模拟结果往往会随着输入数据的空间尺度变化而发生变化。然而,目前的元胞自动机城市增长模型大多没考虑数据的空间尺度特征,本文拟通过改变模型中输入数据的空间尺度来验证元胞自动机城市增长模型对尺度的敏感性及其空间尺度特征,并以长沙市为例进行实证研究。研究结果表明:元胞自动机城市增长模型只有在一定的尺度范围内才具有较高的模拟精度,并且模型对尺度具有一定的敏感性,因此为了使模型能够具有较高的模拟精度,并较好地反映城市形态特征,应认真选择模型中输入数据的空间尺度。  相似文献   

18.
《测量评论》2013,45(96):81-87
Abstract

Several articles which deal with instruction in surveying at the university have appeared recently in the E.S.R., notably ones by P. N. Ray (xii, 89, 104–110), A. Stephenson (xii, 91, 217–222)and K. R. Peattie (xii, 94, 376–379). Particular attention is given in them to courses for engineering students. It may be of interest to readers of this Journal to hear of a survey course for geography students. Although the pattern varies at different universities, it is common to find instruction, for all geography students, in simple surveying, with practice in chain and compass surveys and the use of the plane table, while Honours students may select surveying at a late stage in the course as one of the branches of the subject in which they are to specialize. Below are set out details of a course given at University College, Ibadan, Nigeria.  相似文献   

19.
地理模型及GIS集成   总被引:4,自引:1,他引:3  
地理模型是揭示地理现象的过程、结构和地理现象之间联系的概念性和本质性的表示方式。地理信息系统的发展为地理模型的应用提供了手段和工具,同时地理模型的成熟和应用丰富了地理信息系统的空间分析功能。在地理信息系统中集成地理模型的方法有外部工具型、松散整合型、系统内嵌型。  相似文献   

20.
Abstract

The paper presents a GIS model for mapping soils in the semi arid region of Israel. The model is based on a priori knowledge of the soil generating factors in the study area, namely (1) the parent‐material (lithology) which determines the origin of the soil; and (2) the relief (including the drainage patents) which is responsible for erosion, deposition, and leaching processes along the catena. A special attempt was made to represent soil belts in small subwatersheds with different parent‐material. The width of these belts can be varied as a function of the local relief.

We believe that GIS techniques, in contrast to conventional survey and mapping methods, have the potential to overcome the manpower and fiscal restrictions which limit monitoring of large areas and areas which are for different reasons difficult to access. However, systematically generalizing a spatial model for a large area may introduce some errors, either due to local variations which were not taken into account, or regional variations.  相似文献   

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