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1.
Abstract

The concept of GRASS (Geographic Resources Analysis Support System) as an open system has created a favourable environment for integration of process based modelling and GIS. To support this integration a new generation of tools is being developed in the following areas: (a) interpolation from multidimensional scattered point data, (b) analysis of surfaces and hypersurfaces, (c) modelling of spatial processes and, (d) 3D dynamic visualization. Examples of two applications are given-spatial and temporal modelling of erosion and deposition, and multivariate interpolation and visualization of nitrogen concentrations in the Chesapeake Bay.  相似文献   

2.
CAG '74     

Houses in inner-city areas, because of their age, suffer the depredations of functional obsolescence and decay. Some, however, have sound locations and are able to assemble economic forces that precipitate rehabilitation by both renters and owners. Accompanying restoration is a concomitant increase in market value and in population density, the corollary of which is a reduction in lot size. This process is modeled by graphically synthesizing elements of location theory, urban growth theory, and principles of economics.  相似文献   

3.
This paper considers the appropriateness of typologies of urban retailing areas based on multivariate functional data. The findings of a case study in which statistical and graphical methods were employed within the framework of multivariate ordination are presented. It is shown that the functional attributes of retail areas are closely associated with their location, accessibility, quality, morphology, size, period of development, and socioeconomic character.  相似文献   

4.

This paper examines the need to carry out primary health care administration, programming and planning beyond the established 110 districts in Ghana. The framework for delimiting the sub-districts is offered by the availability of digital data such as the district boundary, site location, road network and population. Using the specified travel distance from predetermined sites, network analysis generates approximate polygons around the health centres to create functional areas ? the health sub-districts. Additional sites are proposed based on a set of criteria which includes proximity, centrality, population and existing level of infrastructural development in an attempt to improve coverage and bring the total utilization of health facilities closer to 100% in the study area.  相似文献   

5.
Abstract

The multidimensional nature of many types of data in modern geography calls for creative and innovative approaches to their analysis. Statisticians have recently developed methods for exploring and visualizing large, multivariate datasets, but cartographers and geographers in general have only recently begun to integrate these methods for use with spatial and spatiotemporal datasets that are multivariate in character. This article will present an example of such an integration—an environment for visualization of health statistics—as a case study to demonstrate the philosophical and practical advantages of geovisualization systems for the exploration of complex spatiotemporal information. Emphasis is placed on the encouragement of creative thinking about geographic phenomena through the use of such data-rich graphical tools.

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6.
Abstract

Growth of industrial/office parks in metropolitan areas is the result of the truck-auto freeway complex, changes in technology, increased i market orientation of activity, and the desire for facilities with favorable public images. This article reviews the historical development of industrial and office parks, and speculates about their behavioral characteristics at the national and metropolitan scale, including the process of decentralization. The locational and functional characteristics of these parks in Atlanta, Georgia are treated as being typical of those in a regional capital. Readers no doubt will be familiar with similar developments in their own communities and can use this paper as a resource to guide their investigations.  相似文献   

7.
ABSTRACT

Studies on the riding modes of shared bicycles have aimed to heighten the understanding of cycling characteristics. This paper analyzes the spatiotemporal riding modes of shared bicycles based on tensor decomposition in Beijing, China. Two third-order tensors are constructed for the origin and destination points of shared bicycles in the day, hour, and space dimensions. Three factor matrices explicitly reveal two modes, three modes, and six modes in the day dimension, hour dimension, and space dimension, respectively. The relationships among the different modes in the three dimensions are demonstrated in an interaction table. Further, the density for different types of points of interest (POIs) are calculated to further analyze the potential riding purpose for different riding modes. Notably, the main POI types for the areas of O2 and D2 modes are consistent with the areas of D3 and O3 modes, which reflects the tidal characteristics of the commuting activities of shared bicycles. The main functional areas are inferred according to the riding modes and POIs, which enables verification of the correctness of the obtained riding modes to some extent. By method comparison, tensor decomposition shows the advantage of being able to reveal the spatiotemporal modes among multiple dimensions.  相似文献   

8.
Abstract

The agricultural system in West Pakistan is largely subsistence-oriented, and extensive areas are devoted to produce the low-value crops. Only a small portion of the total cropped area is used to raise cash crops. However, there are regional differences in cropland use in the province. The study focuses on regional variations in the cropping patterns in West Pakistan by establishing the crop combination areas. The crop combination areas also point out a land-use distinction between the areas. Also, the changes in some of the important crops in terms of their land occupancy in the area during the fifteen-year period have been analyzed.  相似文献   

9.
ABSTRACT

As a tribute to the massive contribution of our friend and colleague Graeme Hugo to the population and settlement geography of Australian rural areas, this paper presents a longitudinal study from his home State. It forms part of a wider study of the long-term demographic relationships between Australia’s rapidly growing regional cities and their surrounding functional regions. Of particular interest is the question of what effect the accelerating concentration of population and economic activity into a given regional city will have for the longer term demographic sustainability of its functional region as a whole. Taking the case of Port Lincoln, regional capital of most of South Australia’s Eyre Peninsula, it examines the nature of change in the functional region over the period 1947–2011, and investigates the forces feeding, and partly counteracting, the population concentration process, informed by concepts of evolutionary economic geography. In particular it traces the demographic impact (particularly differential migration and ageing trends) of exogenous shocks to the region’s essentially primary productive economic base during the period of major change from 1981 to 2011.  相似文献   

10.

Data from transportation studies are used to examine changes in accessibility to employment opportunities in the Milwaukee urban area from 1927 to 1963. Low-status areas of the city tended to experience the greatest decreases in employment accessibility compared with other parts of the urban area. Furthermore, increasing levels of employment accessibility were associated with greater amounts of new housing, whereas decreases in housing vacancies and population occured in areas with declining accessibility to employment.  相似文献   

11.

Because of its species-rich hay meadows and old pollards that are traditionally managed, Ulvund in Myrkdalen, Voss, is one of 14 areas in Hordaland county that are considered to be of special interest for cultural landscape conservation. The spatial patterns of species richness were investigated in hay meadows at Ulvund. Two main types of vegetation were recognised in managed meadows. Unfertilised and species-rich areas with a rather short field layer were situated in the steep parts of the meadows. Fertilised and species-poor areas with a high field layer were situated on flat or gently sloping areas. This spatial pattern is recognised in other west Norwegian hay meadows as well and is very likely linked to historical differences in land management; the flatter areas were formerly used as heavily fertilised permanent tilled fields for grain production, while the steep areas were used for hay production. As the conservation value largely lies in small, localized parts of the farms, conservation management actions can also be localized and thus feasible under modern conditions.  相似文献   

12.
ABSTRACT

Peri-urban areas are the interface between urban and rural regions, with these regions traditionally acting as foodbowls for adjacent urban areas. This peri-urban agriculture provides a diverse suite of benefits to urban areas. Increasingly, however, peri-urban areas are being converted to residential uses, driven in part by higher land values secured for land converted for residential development. In Sydney, planning and development has tended to treat peri-urban areas as ‘suburbs in waiting’. Using a Foucauldian governmentality approach, this paper investigates the prevailing rationalities in metropolitan-level strategic planning documents—in particular A Plan for Growing Sydney and the Draft South West District Plan—and how these rationalities relate to peri-urban agriculture. Our analysis shows that the three overarching rationalities—the global city, the compact city and the sustainability agenda—frame the urbanisation of peri-urban agricultural lands as necessary and inevitable, and only integrate agriculture as part of the future of the city of Sydney when it can be rationalised within the ‘global city’ narrative. As a result, peri-urban areas are not considered to have unique planning needs, but are imagined as latent spaces that will enable Sydney to meet its housing and job targets through their future development.  相似文献   

13.
《The Journal of geography》2012,111(3-4):153-168
Abstract

This article examines key topics and concepts in the cities and urban land use section of the Advanced Placement human geography course. Among the topics discussed are definitions of urbanism, the origin and evolution of cities, functional character of contemporary cities, the built environment and social space, and responses to urban growth.  相似文献   

14.
21世纪中国主要粮食产区的空间格局特征   总被引：1，自引：0，他引：1  
Grain production is an important issue for the national economy and the livelihood of the Chinese people. It serves as the foundation of national development and social stability. China is a major grain producer as well as a major grain consumer. The grai…  相似文献   

15.
《The Journal of geography》2012,111(4):224-229
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16.

The diurnal course of large hail varies over the United States. The time of maximum of large hail changes from near 1500 hours on the east coast to between 1800 and 1900 hours on the Great Plains. The north-to-south differences are smaller except near the Gulf Coast, where secondary maxima occur. In some areas the time of maximum of large hail differs from the maxima times of tornadoes, heavy rain, and thunderstorms.  相似文献   

17.
《The Journal of geography》2012,111(5):230-237
Abstract

The connotations and meanings of the term “frontier” have undergone several transitions, mainly from border areas through advance settlement regions to developing regions. These transitions are highlighted in several ways: tracing the idea of the frontier back to its original meanings; providing a critical perspective on experiments for redefinitions of frontiers; and, finally, drawing some conclusions from these redefinitions, notably in light of the evolving global economy.  相似文献   

18.
《The Journal of geography》2012,111(5):275-284
Abstract

Disadvantaged migrants to metropolitan areas are segregated by race, ethnicity, or socioeconomic status within the residential areas of central city poverty neighborhoods. Whereas black migrants are generally restricted to ghetto space, regional cultural similarities and feedback in the social communication network are important to the residential location of lower class whites. The urban settlement patterns of a sample of recent disadvantaged white migrants to Indianapolis, Indiana, vary from the clusters of migrants from Appalachia and the South to the more dispersed pattern of migrants from Indiana, Illinois, and Ohio, and other metropolitan areas. The residential location of migrants from Appalachia and the South is geographically restricted by cultural constraints, and heavy reliance upon a limited network of friends and relatives in the housing search. However, the sociocultural resources of the Midwest group and the previous urban experience of metropolitan migrants increase the range of housing opportunities in Indianapolis that are available and known to them.  相似文献   

19.
This paper quantitatively explores farmers＇ vulnerability to flood in the Poyang Lake Region （PLR） with the supports of GIS spatial functions. The analysis consists of three major steps, which is based on the spatial unit of township. Firstly, the spatial extent and characteristics of flood risk areas were determined using a digital elevation model （DEM） derived from the 1：50,000 topographic map. Secondly, for each of the township, six indices indicating the economic activities of local farmers were calculated. These indices are： rural population proportion, cultivated land proportion, GDP per unit area, employment proportion of primary industry, net rural income per capita and agricultural income proportion. These six indices were then normalized and used for later vulnerability assessment. Thirdly, the normalized indices （as GIS data layers） were overlaid with the flood risk areas to produce the risk coefficient for each township and to calculate the overall vulnerability for each township. The analysis results show that in the PLR there are high flood risk areas where the farmers＇ livings are seriously influenced or threatened. About 55.56% of the total 180 townships in the flood risk areas have a high degree of flood vulnerability. The townships under flood risk are mainly distributed in the areas around the Poyang Lake and the areas along the ＂five rivers＂.  相似文献   

20.

Maps are an important source of data for planning and land use analysis of flood-prone areas. Map users with inadequate training are not aware that map errors can lead to ineffective decisions. Although inherent errors introduced by transformation, map construction, and symbolization are never identified on maps, they limit the effectiveness of maps as sources of data. Additional vertical and horizontal errors can be introduced during map use. Knowledge of the sources and amounts of such errors should result in more effective decisions regarding flood hazards.  相似文献   

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