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1.
Judith A. Rees 《Geoforum》1981,12(3):211-225
Conventional economic appraisals of the water industry have concentrated on economic efficiency defined almost entirely in allocative terms, the key issues being the efficiency with which available water resources are allocated between users and with which factors of production are invested in new facilities. Since marginal cost pricing has been viewed as the mechanism theoretically capable of bringing about optimality in resource allocation, assessments of water industry practices have all too often been reduced to reiteration of the extent to which current pricing practices diverge from the theoretical optima. This paper, based on empirical work on water suppliers in both Britain and Australia, questions the relevance of this conventional approach.First, it is argued that the concentration on allocative efficiency has diverted attention from the equally crucial issue of whether the industry is efficient in managerial, technical and product terms. Since technological efficiency must exist in an industry before a Pareto optimal allocation of resources can occur, the presupposition, in papers which argue that the introduction of optimal pricing rules will ensure allocative efficiency, must be that the industry is already producing an appropriate product using least cost production methods. No such presupposition can be made in an industry where the profit motive and competitive forces do not operate.Second, it is argued that optimal pricing policies can only produce optimal resource allocations if consumers act in a prescribedly rational way to the prices set. Although it is well known that ‘second-best’ pricing rules may be needed to counter inefficient conditions prevailing in other sectors of the economy, the effect of market imperfec- tions on the way consumers react to prices has been less well analysed. Using results from a study of firms' reactions to trade effluent charges, it is shown that the structure of companies and the way they operate their revenue and capital budgets may severely limit the effectiveness of the price mechanism in ensuring allocative efficiency.Finally, the paper considers the ‘equity’ with which the costs of water services are distributed between consumers. Once again it is argued that the issue has been neglected since the distribution of income is irrelevant to the achievement of allocative optimality in Paretian terms. Evidence is presented that contradicts the popular myth that, although current pricing arrangements may be less than efficient, they are at least ‘broadly fair’. It is shown that, in practice, price discrimination against low income consumers is widespread, and this can hardly be regarded as equitable, whatever definition of equity is used.  相似文献   

2.
大庆油田西部地区地下水动态监测网优化设计   总被引:2,自引:1,他引:2  
大庆油田地下水动态监测,网(用水文地质定性方法建立)历经30多年的开采,需要进行定量优化设计,本次研究采用卡尔曼滤波技术与地下水流系统确定--随机性数值模型相耦合的方法,首先对现有监测网进行质量评价,计算结果表明:监测网在漏斗区(地下水集中开采区)应增加监测孔的数目,调整监测孔的位置,为此,我们拟订了6套12个备选方案,从中选取了由88个监测孔组成的监测网,此监测网无论从监测目标上还是经费上都是最优的。  相似文献   

3.
In contrast to overpopulated Java the neighbouring island of Sumatra still provides huge unused land reserves. However, by far not all of these reserves can be regarded as real agricultural potentials, e.g. for resettlement projects. Especially the poor soils often prove an agricultural handicap. Besides soil fertility the existing vegetation has to be conidered. Thus, for example, the so called “alang alang grass savannas” in general show better potentialities than forest areas, while most of the swamps prove rather unsuitable for agricultural development. With regard to the already existing landuse types the cultivation of perennial bush- and tree crops, for instance rubber, seems to be best suited for further expansions. An expansion of annual food crops would be feasible too, however only be applying heavy capital inputs; here wet rice cultivation would be more appropiate than the permanent cultivation of annual upland crops like cassava, maize, etc. The traditional shifting cultivation does not serve as an alternative any longer. Animal breeding will have its difficulties, with the exception of certain highland areas. Taking into account all ecological, social, and economic reservations it is concluded that, in spite of considerable restrictions, a good part of the land reserves in southern Sumatra could still be opened and used successfully for agricultural purposes.  相似文献   

4.
Accurate prediction of settlement for shallow footings on cohesionless soil is a complex geotechnical problem due to large uncertainties associated with soil. Prediction of the settlement of shallow footings on cohesionless soil is based on in situ tests as it is difficult to find out the properties of soil in the laboratory and standard penetration test (SPT) is the most often used in situ test. In data driven modelling, it is very difficult to choose the optimal input parameters, which will govern the model efficiency along with a better generalization. Feature subset selection involves minimization of both prediction error and the number of features, which are in general mutual conflicting objectives. In this study, a multi-objective optimization technique is used, where a non-dominated sorting genetic algorithm (NSGA II) is combined with a learning algorithm (neural network) to develop a prediction model based on SPT data based on the Pareto optimal front. Pareto optimal front gives the user freedom to choose a model in terms of accuracy and model complexity. It is also shown how NSGA II can be effectively applied to select the optimal parameters and besides minimizing the error rate. The developed model is compared with existing models in terms of different statistical criteria and found to be more efficient.  相似文献   

5.
This paper raises questions regarding the desirable sizes of retail facilities within an existing urban system. We address questions of efficiency by reference to a social welfare function and by reference to profit maximization by developers. To this end we utilize a gravity-type simulation model and apply it in the case of Haifa, Israel based on a unique data base. Based on simulations of a single developer who owns all the retail facilities the optimal locations yield large retail facilities away from residential areas and smaller ones in the locations closer to the buying power. In the case that each facility is owned separately, stepwise optimization yields optimal order of development, first at locations in close proximity to the buying power. In the early stages of the development of a retail system the revenues are expected to be high and the sizes of retailers moderate. The total amount of retail space supplied by the modern retailers in reality is significantly higher than the amount suggested by the optimization tests.  相似文献   

6.
岳传明 《山东地质》2014,(10):84-86
当前在国家稳增长、调结构、扩内需的背景下,深挖潜力,节约集约用地已成为土地利用工作的当务之急。利津县通过严格按照产业政策供地、加强农村集体建设用地流转、实施城乡建设用地挂钩项目等措施,提高了用地效率,促进了节约集约用地。但工作中应就土地节约集约利用水平不高、用地空间组织形式相对落后等问题,严格用地管理,优化用地模式,强化土地集约利用。  相似文献   

7.
朱宁  施建勇  陈海丰 《岩土力学》2006,27(2):257-260
在静压桩贯入问题的研究中,常用无限土体中圆孔扩张法来模拟桩端对土体的扩张。实际上,压桩问题属于半无限问题,必须考虑从无限问题转化到半无限问题后地面边界处应力的差异。针对半无限问题中地表应力的修正,在现有研究的基础上引入了应力函数解答来求解弹性条件下半无限问题,很好地修正了地表应力,得到了相应的解答。与原有的解答相比,提出的解答能够更好地反映半无限的特性,为进一步分析压桩问题奠定了基础。  相似文献   

8.
在物探工作设计阶段,主要参考测区的地质图和地形图,进行控制点的选取和测网的布置.但这些地形图往往是七十年代、八十年代绘制的,随着自然环境的变化,人类活动的改造,可能发生了很大的变化,如湖泊水位变化,居民点变迁、城市的扩建、地质灾害等.随着"3S"集成技术的不断成熟,可以利用带地理参数的遥感影像对地形图的变更部份进行修正...  相似文献   

9.
Conclusion Despite its uniqueness, the vitality inherent in the rural structure of Israel is of particular interest to other developing regions with a predominant rural-agricultural population. Latin American countries, for example, are investing considerable resources in the development of new lands through construction of penetration roads and other infrastructure. Several countries have created regional development authorities; some have policies designed to attract private investments into virgin areas.13) The general emphasis tends increasingly toward state-initiated and planned settlement, often in conjuction with agrarian reform programs — an approach dictated both by economic efficiency and welfare criteria.Past experience has shown that the rural population has to be organized in viable communities in order to become amenable to economic and cultural integration. Communities must likewise be spatially organized in an optimal way that will make it possible to provide them with amenities and so direct their production for the purpose of achieving economic status. At the same time, maximum flexibility must be preserved to fit varying developmental stages, since physical plans once carried into effect are extremely difficult to modify.In order to reduce the social and economic pull of existing urban centers it may be advisable to develop new settlement areas as self-sufficient enclaves, independent to some extent from the facilities existing in the region. The settlements would share the national infrastructure of communications and public services, but would gear their production to regional as well as extra-regional demand, bypassing the traditional local market place. Then, as the new communities consolidate as social and economic entities, the options for collaboration or competition with existing central places can be laid open on a more equitable basis.Admittedly such sheltered development may affect the role of the local intermediary and lessen the commercial activities of the urban sector, but it would also stimulate the development of an independent framework of handling, marketing, and an increasing degree of processing the settlements' produce. These complementary activities would help to retain part of the added value of the production and generate new sources of employment for successive village generations. The delay in the growth for the region's total output may well be worthwhile for achieving that social and economic transformation which in turn may lead to a more balance and sustained development of the entire region.14)  相似文献   

10.
城镇污水处理设施的建设和维护,对现代城市的可持续发展、确保水环境不受污染具有重要意义。以江苏省淮安市为例,以乡镇为评价单元,分析污染源的空间格局、变化趋势及其环境影响、污水处理设施需求,研究城镇污水处理能力与废污水排放的空间匹配格局。综合考虑废污水排放特征、污水处理厂的实际能力与设计能力,利用ArcGIS空间分析工具,将研究区划分为治污潜力释放类型区、治污增强类型区和维持现状类型区,对比分析废污水排放与治理能力缺口,提出污水处理设施建设与运营导向,为城镇污水处理厂建设选址与布局优化提供科学依据。  相似文献   

11.
J. Connell Dr. 《GeoJournal》1979,3(6):587-598
The PNG cattle industry grew slowly until after 1963 when both expatriate-owned ranches and locally-owned smallholder schemes expanded with the assistance of foreign aid. This expansion continued throughout the country until the mid-1970's when the number of cattle in both sectors began to decline and production stabilised. Ranches faced a future of political uncertainty whilst the prestige associated with being the owner of a smallholder scheme was not reflected in increased incomes for those involved; demands on labour were high, management skills lacking and incomes from cash crops were usually higher. The economic and social differentiation that followed cattle smallholding emphazised existing disparities. Increased local demands for beef imports have encouraged a revised national policy directed at producing beef on locally owned but principally expatriate managed ranches on a limited number of available grassland sites. This policy which is now being implemented may also minimise both local economic defferentiation and regional inequalities.Fieldwork was completed in 1979 during secondment to the institute of Applied Social and Economic Research in Port Moresby, Papua New Guinea. I am grateful to them for logistical and financial support.  相似文献   

12.
The expansion of multinational corporations into agricultural production around the world is resulting in new forms of engagement in specific places. In the context of neoliberal restructuring, these engagements are tied to shifting landscapes of societal, governmental and industry-based perceptions on the role of corporations in labor regimes. But how are these engagements developed and how do they connect to the everyday lives of workers? In India, when Monsanto expanded into hybrid cotton seed production in the early 2000s, the corporation came under pressure to address concerns over the widespread employment of children and young workers for seed pollination. In response, the corporation developed an approach to child labor that, I argue, works to reinforce generalized and problematic notions of childhood and work. Corporate engagements in global agriculture need to be situated in time and space, and alongside the experiences of workers. Children experience attempts to shape their patterns of work and mobility as a series of surmountable obstacles, disconnected from the process of deciding whether or not they will engage in this work. Drawing on qualitative fieldwork in Gujarat and Rajasthan, and documentary analysis of public documents, I outline the development of a corporate response to child labor and place it within the context of the rise of corporate social responsibility, global ideas of child labor, and in the specific case of cotton seed production in western India. I demonstrate that contextualized geographies of working children in globalized agriculture reveal the nature of multinational corporations’ engagements in specific places.  相似文献   

13.
地下水观测井网优化设计   总被引:1,自引:0,他引:1  
本文比较系统地论述克立金方法的基本思想,结合数学规划方法,推导出克立金方程组,并以现有的神头电厂贮灰场地下水观测井网的质量评价为基础,考虑观测井网优化设计中目的和经费投入量,拟定备选方案,分别计算出估计误差方差分布,经比较分析,选取一个最佳方案,分析结果表明,应用克立金方法可以解决地下水观测井网的优化问题。  相似文献   

14.
Following the catastrophic and devastating Atlantic Hurricane seasons in 2004 and 2005, there has been increased interest in formulating planning directives and policy aimed at minimizing the societal impacts of future storms. Not all populations will evacuate an area forecast to be affected by a hurricane, so emergency managers must plan for these people who remain behind. Such planning includes making food, water, ice, and other provisions available at strategic locations throughout an affected area. Recent research has tackled problems related to humanitarian and relief goods distribution with respect to hurricanes. Experience shows that the torrential rains and heavy winds associated with hurricanes can severely damage transportation network infrastructure rendering it unusable. Scanning the literature on hurricane disaster relief provision, there are no studies that expressly consider the potential damage that may be caused to a transportation network by strong storms. This paper examines the impacts of simulated network failures on hurricane disaster relief planning strategies, using a smaller Florida City as an example. A relief distribution protocol is assumed where goods distribution points are set up in pre-determined locations following the passage of a storm. Simulation results reveal that modest disruptions to the transportation network produce marked changes in the number and spatial configuration of relief facilities. At the same time, the transportation network appears to be robust and is able to support relief service provision even at elevated levels of hypothesized disruption.  相似文献   

15.
Present development and future planning of Canberra, the Australian National Capital, is described as an example of modern town planning emphasising the spatial and functional organisation of the urban area. Canberra is a rapidly growing city and is being expanded by the creation of new dispersed satellite towns which are grouped around Inner Canberra in three growth corridors. The towns are structured into a hierarchical order of centers and provide a large range of services and facilities as well as a concentration of employment opportunities. Although the towns are self-supporting to a great degree, they remain integral parts of the metropolis with the City center providing the greatest range of services and facilities, as well as employment. One of the main problems facing the Capital is the inefficiency of public transport and accordingly the strong reliance on private motor vehicles, which will be difficult to overcome If present population densities are not substantially increased.  相似文献   

16.
Sharma  Madhuri  Abhay  Rajesh Kumar 《GeoJournal》2022,87(4):797-819

One out of three people in India is urban. In 2011, there were about 53 urban agglomerations larger than 1 million population as against only 35 in 2001. Much of this urban expansion has been occurring in the country’s largest metropolises including the National Capital Territory of Delhi which has expanded horizontally and vertically both. This has also added to overall decline in its already dilapidated housing stock and quality of life. Delhi, a historical hub for regional, national, and international commerce, and a place for the socio-political elites, has failed to provide basic life amenities to its average citizens. This research critiques the (un)sustainable elements of Delhi’s urbanization and concomitant decline in basic amenities pertaining to quality-of-life by examining the growth and expansion of its urban-built-up areas during 2001–2011–2020 and provides nuanced insights into its ‘livability’ by examining select quality-of-life attributes. The LANDSAT imageries for 2010 and 2020 are used to measure NDB-Index that assesses its built-up area and change, which are later corroborated with Census household data to examine change in its ‘livable’ and ‘dilapidated’ housing structures. Significant sub-regional disparity exists in the availability of good and livable homes, with almost 20–30% of several districts still without drinking water source inside premises. However, significant progress is also noted for basic amenities like lighting, latrine and bathing facilities, and majority of Delhi’s built-up area has expanded along newer developments and transportation corridors. This calls for goal-oriented strategic interventions by policymakers to help achieve the SDG-11 on Sustainable Cities.

  相似文献   

17.
The historical processes of industrialization and urbanization have caused a variety of urban patterns in the largest conurbation of Central Europe, the Ruhr region, that now has to pass a period of economic recession and stagnation.After an outline of the historical development the existing economic regionalization is enlarged by a system of subregional areas which is based on the various urban patterns of the region. This system shows striking coincidence with the present central place structure. Small scale population trends can be explained by and future planning objectives may be derived from it.  相似文献   

18.
D.R. Diamond 《Geoforum》1984,15(1):33-38
This paper notes the recent growth of public policy evaluation studies and pays particular attention to those policies with avowed spatial objectives. It seeks to establish the general nature of these diverse studies and their relationship to geographical analysis. A case study examining the evaluation of regional policy in the U.K. is used to demonstrate the nature of the issues in public policy evaluation and to explore the role of geography in the rapidly growing domain, known most commonly as ‘policy analysis’.  相似文献   

19.
James W. Harrington Jr   《Geoforum》1985,16(4):349-356
Analysis of locational patterns and change within an industry may be assisted by division of industry participants into groups based on corporate and business strategies. These strategies reflect the assets of the companies and the characteristics of the industry. They affect the locational needs, behavior and impact of the companies. Hypothesized effects of strategy are explored in a brief study of U.S. semiconductor manufacturers. Of the possible strategic considerations, corporate diversification and integration, and business scale and cost/price position seem to be the most relevant for this industry.  相似文献   

20.
One of the most important objectives of a manufacturing firm is the efficient design and operation of its supply chain to maximize profit. Paper is an example of a valuable material that can be recycled and recovered. Uncertainty is one of the characteristics of the real world. The methods that cope with uncertainty help researchers get realistic results. In this study, a two-stage stochastic programing model is proposed to determine a long term strategy including optimal facility locations and optimal flow amounts for large scale reverse supply chain network design problem under uncertainty. This network design problem includes optimal recycling and collection center locations and optimal flow amounts between the nodes in the multi-facility environment. Proposed model is suitable for recycling/ manufacturing type of systems in reverse supply chain. All deterministic, stochastic models are mixed-integer programing models and are solved by commercial software GAMS 21.6/CPLEX 9.0.  相似文献   

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