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1.
The bauxite-aluminium industry structure is reviewed to illustrate the character of the threat posed by the formation of the International Bauxite Association (IBA). Bauxite price is a transfer price internal to vertically integrated firms, but Caribbean governments' fiscal revenue needs provoked a consistent tendency towards price increases. Australia is not interested in this or in a bauxite cartel, but rather in developing smelting capacity, exploiting its energy resources, and the elimination of barriers to Australian aluminium imports. Some elasticity estimates previously presented for demand and supply, together with their estimation method and policy implications, are strongly criticized.  相似文献   

2.
Toxic Release Inventory (TRI) data were used to compare average releases (kilograms per metric ton) of paper mills using primarily recovered wastepaper versus mills using primarily virgin wood fiber. Annual releases, for 79 mills, of chlorine, chlorine dioxide, chloroform, acids (hydrochloric and sulfuric), volatile organics (methyl ethyl ketone, methanol, and acetone), and ammonia were compared over the years 1987–1992. Both types of mills reported generally lower toxic releases in 1992 than in 1987; however, toxic releases in all categories were significantly lower from mills using recovered wastepaper than from mills using virgin wood fiber, strongly demonstrating that recycling has added benefits beyond reduced resource consumption. These results suggest that environmental policy should concentrate as much on increasing demand for recycled paper and developing wastepaper collection infrastructure as it does on end-of-pipe pollution abatement.  相似文献   

3.
ABSTRACT: This study proposes that demand management through pricing policies can be used in conjunction with supply management to solve water supply problems. Economic principles are shown to apply to rural residential water use. A demand function for water was developed based on cross-sectional water use data collected in Kentucky. Price was found to be a significant determinant of the quantity of water demanded. A constant price elasticity of -0.92 was found. The demand function was used in a simulation analysis to determine reservoir capacity needed to supply water needs of a rural community. The simulation revealed that price can significantly affect required reservoir storage.  相似文献   

4.
The USA and Canada are each considering measures to reduce general exposure to asbestos. Product bans and workplace exposure rules may each reduce general exposure by reducing domestic asbestos demand. The effectiveness of demand-reducing measures will depend upon the elasticity of asbestos supply to the domestic market. This paper provides calculations of this elasticity for three fibre grade groupings, using a framework that recognizes international trade in asbestos and the joint product nature of most asbestos fibre production. The results suggest that reductions in North American demand result in relatively substantial changes in asbestos use but very small changes in price.  相似文献   

5.
The paper considers the degree to which declining market power explains modifications in pricing behaviour observed since the late 1970s in the North American aluminium, copper, lead and zinc industries. More precisely, it relates those changes in pricing policies to the price elasticity of demand facing the dominant strategic group in each industry, the cost elasticity of supply and to the management's ability to coordinate or internalize conduct decisions. The results suggest that the firms in the copper and lead industries do not hold as a group any form of market power. In the case of the aluminum industry, a notable increase in the price elasticity of demand since the end of the 1970s, a sustained decrease in the concentration ratio and a rigid production process are weakening the presence of market power in that industry. The results are inconclusive in the case of the zinc industry since the determinants of market power move in opposite directions.  相似文献   

6.
ABSTRACT: Prediction of future water demands depends on the degree to which conservation effects can be anticipated. A model developed for the Corps of Engineers shows that choosing a numerical conservation target to be achieved is more meaningful and yields more predictable results than price or price elasticity manipulations. The method developed and then applied to the Kaneohe Bay region of Oahu considers the following determinants of demand: geographic distribution of the users, indoor and outdoor requirements, time - by year and month of the year, precipitation, historical unit usage rates, gross and irrigable acreage of land uses, price for water, elasticity of demand with respect to price, source of the water supply (local private supplies vs. agency supplies), and the percentage conservation savings anticipated in each future period in indoor and outdoor uses of water in each of 40 possible land uses. While developed for use in Hawaii, the model is applicable generally.  相似文献   

7.
The analysis shows the impact of the 'New International Energy Order' on Jamaica, a developing country almost totally dependent on imported oil for satisfying national energy demand. The energy supply/demand situation between 1961 and 1976 and the structure of energy consumption by major sectors of the economy are discussed. The high income elasticity of commercial energy demand and the increase in the energy intensity of the economy is directly related to expansion of the alumina industry. The structural problems of decoupling GDP and energy growth are indicated. In particular, the impact of the 'New Energy Order' on the development prospects of major bauxite/alumina producing countries which are deficient in indigenous primary energy resources is assessed. Finally, the indigenous resource base is outlined and the major elements of the five-year (1978–1982) national energy plan summarized.  相似文献   

8.
This study develops a modelling framework within which the effects of technology choice and policy on the sustainability of cities may be assessed. A life cycle accounting system for environmental impacts is combined with systems analysis, to represent the flows of resources into cities, the wastes and pollution generated and the technological choices available in an urban environment. The approach is demonstrated through a case study of the demand for paper and management of wastepaper. The case study questions the applicability for paper of the accepted 'hierarchy' of waste management techniques; incineration imposes lower environmental costs than recycling, and consequently lower total costs under some circumstances.  相似文献   

9.
ABSTRACT: An integral part of evaluating the net benefits generated by an existing or proposed irrigation project is the assessment of the associated impacts in commodity markets. Traditionally, these impacts have been measured by either assuming no change in commodity prices and calculating net returns to project farmers, or by allowing commodity prices to fall in accordance with a given elasticity of demand and subtracting commodity production costs from the associated area under the commodity demand curve. In either case, it is implicitly assumed that supply is perfectly inelastic. This article establishes that traditional approaches to measuring direct benefits are biased. Formulae are presented for calculating the maximum absolute and relative error which may result from using these techniques as a function of project size. Direct benefit estimates are then evaluated for three irrigation projects in Nebraska, illustrating how these results can be used to improve project evaluation procedures.  相似文献   

10.
ABSTRACT: The income and proce elasticity of demand for domestic water is estimated for Penang Island, Malaysia. A cross-sectional analysis of a random sample of 1400 households indicated an income-elasticity of zero for low-income families (per capita income less than US$300) and an elasticity of 0.2-0.4 for higher-income families. A time-series analysis of a subsample of individuals of varying income levels suggests a short-run price elasticity of -0.1 to -0.2. The implications of these results for demand forecasting are discussed.  相似文献   

11.
ABSTRACT: An econometric demand function is estimated for residential water use in Metropolitan Manila. Regression results using annual time series data from 1970 to 1981 show that residential water consumption responds to changes in economic variables. Residential demand showed an income (household) elasticity of 0.542 and a combined price elasticity of -0.287. Implications for planning and management are discussed.  相似文献   

12.
ABSTRACT: This study examines water consumption characteristics in Casablanca and analyzes approaches for sustainable water demand management. Research procedures involve the development and estimation of water demand models for the residential/commercial, industrial, and institutional sectors; forecasts of water demand to 2010; and simulation of the effects of a complex of water conservation methods on the forecasted demands. The results indicate that residential/commercial water demand is weakly responsive to price changes (elasticity =?0.448) while institutional water demand is slightly more responsive (elasticity =?0.648). The conservation approaches used in the simulations included public education, plumbing code revisions to require use of water conservation devices, leak detection and repair, pricing policy, metering, and pressure reduction. The results indicate that considerable saving in water use can be attained through a comprehensive water demand management program.  相似文献   

13.
ABSTRACT: This paper develops a model that can be used to forecast the residential elasticity of demand for water within a district. Long-term water conservation programs and revenue and cost decisions hinge crucially on a determination of this elasticity. This study then pools cross-sectional (census) and time series data to generate elasticity forecasts for the Oakland urban area.  相似文献   

14.
The flows of paper are analyzed throughout the papermaking processes, with the year 2007 and Korea defined as the system boundaries. In practice, the statistical data on the production, import and export of paper or pulp can be collected with relative ease from the government and industrial associations. However, the input data regarding the volumes of pulp and wastepaper used in different paper products, such as newsprint, printing papers, sanitary and household papers, specialty papers, and corrugating board base, are difficult to obtain because such information is generally kept confidential in the course of corporate operations.The production processes of paper products in Korea are modeled using information on raw materials, their compositions and production yields of products in order to identify and quantify the amounts of pulp and wastepaper used in each paper product. The material flows of paper are then analyzed based on the calculation model derived from the correlation of input and output flows between the individual processes throughout the entire paper lifecycle. Accuracy analysis using both mean absolute error (MAE) and mean absolute percent error (MAPE) is conducted to verify the amounts of pulp and wastepaper calculated from the proposed model against the volumes of domestically consumed pulp and wastepaper provided in the national statistics. Although the calculated values for the past (i.e., the 1980s and 1990s) differ to some degree from the statistical values, the data for the 2000s have a relatively higher level of accuracy, with the MAPE of the total pulp and recycling volume at 5.39% and 5.30%, respectively, thus validating the adequacy of the proposed modeling method. The proposed calculation model can be effectively used in the material flow analysis (MFA) of paper to reduce the burden of data collection and obtain relatively accurate results.  相似文献   

15.
ABSTRACT: Accurately estimating the price elasticity of demand for irrigation electricity is important to major electricity suppliers such as the Bonneville Power Administration (BPA) of the Pacific Northwest. The BPA has a revenue maximization objective, and the elasticity of demand is central to its rate setting process. Several studies have attempted to estimate demand for irrigation electricity, but none has explicitly included federal agricultural policy and program variables. Tins paper discusses how agricultural programs may influence farmers irrigation decisions and thus their demand for irrigation electricity. It suggests that existing programs serve to make farmers more responsive to electricity rate increases than would otherwise be the case. Thus, studies that fail to include them may underestimate the responsiveness of farmers to electricity rate increases.  相似文献   

16.
Ensuring an adequate, reliable, clean, and affordable water supply for citizens and industries requires informed, long-range water supply planning, which is critically important for water security. A balance between water supply and demand must be considered for a long-term plan. However, water demand projections are often highly uncertain. Climate change could impact the hydrologic processes, and consequently, threaten water supply. Thus, understanding the uncertainties in future water demand and climate is critical for developing a sound water supply plan. In Illinois, regional water supply planning attempts to explore the impacts of future water demand and climate on water supply using scenario analyses and hydrologic modeling. This study is aimed at developing a water supply planning framework that considers both future water demand and climate change impacts. This framework is based on the Soil and Water Assessment Tool to simulate the watershed hydrology and conduct scenario analyses that consider the uncertainties in both future water demand and climate as well as their impacts on water supply. The framework was applied to water supply planning efforts in the Kankakee River watershed. The Kankakee River watershed model was calibrated and validated to observed streamflow records at four long-term United States Geological Survey streamflow gages. Because of the many model parameters involved, the calibration process was automated and was followed by a manual refinement, resulting in good model performance. Long-range water demand projections were prepared by the Illinois State Water Survey. Six future water demand scenarios were established based on a suite of assumptions. Climate scenarios were obtained from the Coupled Model Intercomparison Projection Phase 5 datasets. Three representative concentration pathways (RCPs), RCP2.6, RCP4.5, and RCP8.5, are used in the study. The scenario simulation results demonstrated that climate change appears to have a greater impact on water availability in the study area than water demand. The framework developed in this study can also be used to explore the impacts of uncertainties of water demand and climate on water supply and can be extended to other regions and watersheds.  相似文献   

17.
国土空间规划是统筹区域资源空间配置、开发管理和布局优化的总体方案,在引领区域协调发展上具有重要意义。国土空间规划必然导致土地利用类型及布局的改变,从而引起经济、社会、生态环境等方面的供给与需求变化。本研究从三生空间耦合协调的角度,通过生态系统服务和人类福祉需求的供需关系,揭示三生空间的供需连接与耦合关系。本研究借助 InVEST模型和生态服务价值当量法对生态系统服务供给与需求进行定量分析,同时引入耦合协调度模型与相对发展度模型,通过对生态系统服务供需变化进行耦合协调类型分析,探究国土空间用地结构调整所产生的供需间的协调关系,并用耦合协调状况对国土空间规划效益进行评价。研究发现,在规划期内宜宾市翠屏区生态系统服务供需总体耦合协调度呈现减小态势。2020-2035年耦合协调度从 0.60降低到 0.59,相对发展度由 1.05减小至 1.01。生态系统服务总体供给盈余明显,但由于供需分布空间差异,城镇地区为主要的供给赤字区域。影响生态系统服务需求的主要因素为环境净化需求,城市化指标对生态系统服务供需相对发展度具有较为普遍的负面影响。  相似文献   

18.
One of the most challenging tasks of water supply utilities is planning the timing and quantity of new water supply sources as demand for water consumption grows. Many water supply utilities target on meeting 100% of their customers' needs based on scenario‐based deterministic demand projections numbers even though there are uncertainties in both supply and demand values. This may result in under or overly conservative approach in assessing future needs. In this article, a level‐of‐service concept is introduced to capture a utility's willingness to accept a given level of risk, plan for it, and invoke a management strategy during extreme events than build a facility to accommodate those in planning for new water supply sources. Accounting for uncertainties in both supply and demand help quantify reliability by achieving a prescribed level of service. The major benefit of such an approach for planning future water supply is that it allows policy makers to evaluate the use of adaptive water management strategies and develop supply in an incremental fashion as demand warrants it. For example, if a given level of service cannot be reliably met with the existing system at a future time t, an incremental water supply project would come online to bring the required reliability level up but no more.  相似文献   

19.
Targets to cut 2050 CO2 emissions in the steel and aluminium sectors by 50%, whilst demand is expected to double, cannot be met by energy efficiency measures alone, so options that reduce total demand for liquid metal production must also be considered. Such reductions could occur through reduced demand for final goods (for instance by life extension), reduced demand for material use in each product (for instance by lightweight design) or reduced demand for material to make existing products. The last option, improving the yield of manufacturing processes from liquid metal to final product, is attractive in being invisible to the final customer, but has had little attention to date. Accordingly this paper aims to provide an estimate of the potential to make existing products with less liquid metal production.Yield ratios have been measured for five case study products, through a series of detailed factory visits, along each supply chain. The results of these studies, presented on graphs of cumulative energy against yield, demonstrate how the embodied energy in final products may be up to 15 times greater than the energy required to make liquid metal, due to yield losses. A top-down evaluation of the global flows of steel and aluminium showed that 26% of liquid steel and 41% of liquid aluminium produced does not make it into final products, but is diverted as process scrap and recycled. Reducing scrap substitutes production by recycling and could reduce total energy use by 17% and 6% and total CO2 emissions by 16% and 7% for the steel and aluminium industries respectively, using forming and fabrication energy values from the case studies. The abatement potential of process scrap elimination is similar in magnitude to worldwide implementation of best available standards of energy efficiency and demonstrates how decreasing the recycled content may sometimes result in emission reductions.Evidence from the case studies suggests that whilst most companies are aware of their own yield ratios, few, if any, are fully aware of cumulative losses along their whole supply chain. Addressing yield losses requires this awareness to motivate collaborative approaches to improvement.  相似文献   

20.
This study primarily assesses rainwater supply and demand for Taipei City elementary school to develop a method to derive the rainwater reuse system. This work will help planners build water reuse systems for the sites, and facilitate the water demand of school. This study also analyzes rainfall records from fifteen weather stations in Taipei City to evaluate the rainfall changes in the region's morphology, and measures the rainfall supply in the sub-district of Taipei. The effect of water demand factors is also analyzed with linear regressions applied to estimate the change in monthly water demand for Taipei elementary schools. This work assumes that 35% of total water demand can replaced with rainwater. This work creates an active model for comparisons of each Taipei elementary site rainwater supply trend, demand drift, and maximum rainwater use percentage based on the rainwater reuse system. The efficacy of implementing rainwater reuse in Taipei is identified.  相似文献   

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