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1.
Bauxite supply and demand equations for the largest producers and consumers are estimated with 1958–1982 data. In specifications that include industrial activity indexes, substitute prices and energy costs, these regressors improve the fits and are statistically significant. The own price variable, the Koyck-Nerlove lagged dependent variable, or both, become insignificant, or their estimated coefficients are substantially altered, in relation to their values in price-only models, which overestimate the own price impact and the gap between long- and short-term effects. Industrial activity is the main determinant, followed by the other new regressors. The Jamaican response to price is perverse and significant.  相似文献   

2.
In financial time series, persistence or inertia is a feature usually observable in absolute returns, i.e., a proxy for volatility. Moreover, asset return series should be essentially unpredictable according to the efficiency market hypothesis (EMH) in its weak form. Surprisingly, recent literature has found evidence of anti-persistence in technology stocks and commodity futures returns. Anti-persistence would be indicative of an overreaction of asset prices to incoming information.  相似文献   

3.
4.
In this article the evolution of the aluminium and copper industries is examined, with a view to deriving policy options open to Third World copper producers, which face a declining rate in the growth of consumption. Market structure, company behaviour and performance are analysed for both industries. The impact of energy and general economic crisis in copper and aluminium industries is assessed and market concentration trends are discussed. We conclude that Third World copper producers must change their basic orientation and become seriously involved in market development.  相似文献   

5.
Appropriate assessment of firm sustainability facilitates actor-driven processes towards sustainable development. The methodology in this paper builds further on two proven methodologies for the assessment of sustainability performance: it combines the sustainable value approach with frontier efficiency benchmarks. The sustainable value methodology tries to relate firm performance to the use of different resources. This approach assesses contributions to corporate sustainability by comparing firm resource productivity with the resource productivity of a benchmark, and this for all resources considered. The efficiency is calculated by estimating the production frontier indicating the maximum feasible production possibilities. In this research, the sustainable value approach is combined with efficiency analysis methods to benchmark sustainability assessment. In this way, the production theoretical underpinnings of efficiency analysis enrich the sustainable value approach. The methodology is presented using two different functional forms: the Cobb–Douglas and the translog functional forms. The simplicity of the Cobb–Douglas functional form as benchmark is very attractive but it lacks flexibility. The translog functional form is more flexible but has the disadvantage that it requires a lot of data to avoid estimation problems. Using frontier methods for deriving firm specific benchmarks has the advantage that the particular situation of each company is taken into account when assessing sustainability. Finally, we showed that the methodology can be used as an integrative sustainability assessment tool for policy measures.  相似文献   

6.
This article examines develop-for-import projects financed by development loans and mixed credits supplied by export-import banks and other financial institutions of the central governments of France, Japan and the Federal Republic of Germany. The projects discussed are those producing bauxite, alumina, aluminium, chromium, copper, iron, manganese, molybdenum, nickel and tungsten, in developing market economies, Australia and Canada. The article estimates the volume of these metals committed to France, Japan and FRG to pay for loans and credits, examines the types of financial arrangement involved in develop-for-import projects, and considers the compatibility of these arrangements with the multilateral liberalized world trading system developed by the General Ageement on Tariffs and Trade (GATT) over the past 40 years. To the extent that these arrangements do not fully reflect changes in international market forces, world trade in metals will tend to be distorted and discriminatory.  相似文献   

7.
For sustainable wastewater management, it is essential to consider social, environmental, geological and technical features as well as economic feature in the decision-making process. A limitation of many of the earlier works on wastewater management is that they take into account only financial criteria to make a decision for a given problem. Moreover, the decision-makers’ (DMs) attitude to risk, or optimism degree, when faced with uncertainty is not considered. In this paper, we study the application of risk-based multi-attribute decision-making (RB-MADM) methods to achieve sustainable wastewater management. Consideration of uncertainty, value tradeoffs, and different risk attitudes of decision makers are the important features of the developed methodology. A case study on the Iranian city of Niasar is presented to illustrate how this methodology can be applied to select the most preferred alternative for wastewater management among a set of options. The most preferred option is selected with respect to nine attributes under different optimism/pessimism degrees, using six different MADM methods. The results show that the ranking of options is sensitive to the optimism degree of the DMs. The proposed approach may help policy makers to achieve sustainable wastewater management.  相似文献   

8.
This paper describes the application of exergy and extended exergy analyses to large complex systems. The system to be analysed is assumed to be at steady state, and the input and output fluxes of matter and energy are expressed in units of exergy. Human societies of any reasonable extent are indeed Very Large Complex Systems and can be represented as interconnected networks of N elementary "components", their Subsystems; the detail of the disaggregation depends on the type and quality of the available data. The structural connectivity of the "model" of the System must correctly describe the interactions of each mass or energy flow with each sector of the society: since it is seldom the case that all of these fluxes are available in detail, some preliminary mass- and energy balances must be completed and constitute in fact a part of the initial assumptions. Exergy accounting converts the total amount of resources inflow into their equivalent exergetic form with the help of a table of "raw exergy data" available in the literature. The quantification of each flow on a homogeneous exergetic basis paves the way to the evaluation of the efficiency of each energy and mass transfer between the N sectors and makes it possible to quantify the irreversible losses and identify their sources. The advantage of the EEA, compared to a classical exergy accounting, is the inclusion in the system balance of the exergetic equivalents of three additional "Production Factors": human Labour, Capital and Environmental Remediation costs. EEA has an additional advantage: it allows for the calculation of the efficiency of the domestic sector (impossible to evaluate with any other energy- or exergy-based method) by considering the working hours as its product. As implied in the title, an application of the method was made to a model of the province of Siena (on a year 2000 database): the results show that the sectors of this Province have values of efficiency close to the Italian average, with the exception of the commercial and energy conversion sectors that are more efficient, in agreement with the rather peculiar socio-economic situation of the Province. The largest inefficiency is found to be in the transportation sector, which has an efficiency lower then 30% in EEA and lower than 10% in classical exergy accounting.  相似文献   

9.
Recent years have witnessed a proliferation of studies on public perceptions of carbon capture and storage (CCS), accompanied by efforts to translate such knowledge into toolkits for public engagement and communication. At the same time, both literature and toolkits have paid little attention to the organisational dynamics and views of project implementers with regard to public engagement. Here we investigate the views of project development consortia employees in five European CCS projects, focusing on their experience of organisational norms and structures relating to engagement. Finding that planning for this engagement has, in several cases, been hampered by a lack of shared internal vision on engagement and communication within the project consortia, at least initially, we draw upon the socio-technical approach to technology embedment and new institutional theory, to observe that internal organisational alignment is crucial in multi-organisational projects when seeking effective public engagement and communication. We observe that this aspect of internal organisation is not yet reflected in the toolkits and guidelines designed to aid engagement in CCS projects. Engagement guides need to direct the attention of project implementers not only in specific outward directions, but also towards reflexively considering their own internal structures, perspectives, motivations, expectations and aims in relation to engagement and communication practice.  相似文献   

10.
《Resources Policy》2005,30(2):101-106
The purpose of this paper is to construct and empirically test a model designed to determine the link between market concentration and price with separate effects of market-power and cost-efficiency in change of industrial concentration. The analysis is conducted within the context of a single oligopoly, specifically, the US primary aluminum industry. Using time-series data, the model indicates that both market-power and cost-efficiency effects are significant resulting in unwavering prices despite diminishing market concentration in the industry throughout the sample period.  相似文献   

11.
Supply to electrical pumpsets for irrigation purposes accounts for about 25% of the total electricity sold in India. The number of electrical pumpsets is expected to increase from 8.5 million in 1989–90 to 10.5 million in 1994–95. Low load factors (10–12%) and low densities (1–4 pumpsets/km2) mean large investments for the electric utility in order to supply electricity for irrigation. It is reported that there exists a potential to save at least 10% of the electricity supplied to this sector by means of simple retrofit measures. However, conditions in the field pose constraints to such retrofits. Some of those constraints are highlighted in this paper. It is also suggested that immediate attempts be made to ensure that all new connections are energy efficient. This paper suggests that the additional cost incurred to ensure new energy efficient connections and to maintain retrofit energy efficient pumpsets must be looked on as a necessary cost for energy efficiency.  相似文献   

12.
This paper presents potential energy savings by installing high-efficiency motors instead of existing ones and their impact on greenhouse gases emissions reductions. This research study of the energy efficiency of electric motors has been performed in a typical thermal power plant. In the literature, the focus has been mainly on separate and away electric motors from operating facilities. The important advantage of this paper over other studies is that it uses the actual motors’ efficiency in the evaluation. The gains both in terms of electrical energy savings and in terms of financial economy by using high-efficiency motors have been discussed. As a result, the energy saving can be expected as 12.6% at the operating rate. This excellent result also reduces greenhouse gas emission by 1,423 tons every year. The analysis of the data provided an overview on energy losses often generated by the degradation and rewinding of electrical motors. This study represents very encouraging results that will help energy managers of industrial plants to become more involved in energy efficiency strategies.  相似文献   

13.
Each National Park Service unit in the United States produces a resources management plan (RMP) every four years or less. The plans commit budgets and personnel to specific projects for four years, but they are prepared with little quantitative and analytical rigor and without formal decision-making tools. We have previously described a multiple objective planning process for inventory and monitoring programs (Schmoldt and others 1994). To test the applicability of that process for the more general needs of resources management planning, we conducted an exercise on the Olympic National Park (NP) in Washington State, USA. Eight projects were selected as typical of those considered in RMPs and five members of the Olympic NP staff used the analytic hierarchy process (AHP) to prioritize the eight projects with respect to their implicit management objectives. By altering management priorities for the park, three scenarios were generated. All three contained some similarities in rankings for the eight projects, as well as some differences. Mathematical allocations of money and people differed among these scenarios and differed substantially from what the actual 1990 Olympic NP RMP contains. Combining subjective priority measures with budget dollars and personnel time into an objective function creates a subjective economic metric for comparing different RMP’s. By applying this planning procedure, actual expenditures of budget and personnel in Olympic NP can agree more closely with the staff’s management objectives for the park.  相似文献   

14.
This article investigates the impact that the electricity tariff reform is likely to have on investments in renewable energies (i.e., photovoltaics) and the adoption of energy efficiency measures (i.e., installation of heat pumps and efficient home appliances) in the residential market in Italy. The study develops detailed cost comparisons and simulations considering two different investment scenarios (before and after the reform) to conclude that the reform will: (i) have a negative impact on investments in photovoltaic systems; (ii) favor the adoption of energy efficiency measures, such as efficient home appliances.  相似文献   

15.
Water reuse is an emerging and promising non-conventional water resource. Feasibility studies are essential tools in the decision making process for the implementation of water-reuse projects. However, the methods used to assess economic feasibility tend to focus on internal costs, while external impacts are relegated to unsubstantiated statements about the advantages of water reuse. Using the concept of shadow prices for undesirable outputs of water reclamation, the current study developed a theoretical methodology to assess internal and external economic impacts. The proposed methodological approach is applied to 13 wastewater treatment plants in the Valencia region of Spain that reuse effluent for environmental purposes. Internal benefit analyses indicated that only a proportion of projects were economically viable, while when external benefits are incorporated all projects were economically viable. In conclusion, the economic feasibility assessments of water-reuse projects should quantitatively evaluate economic, environmental and resource availability.  相似文献   

16.
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   

17.
In developing countries, large dam projects continue to be launched, primarily to secure a time-stable freshwater supply and to generate hydropower. Meanwhile, calls for environmentally sustainable development put pressure on the dam-building industry to integrate ecological concerns in project planning and decision-making. Such integration requires environmental impact statements (EISs) that can communicate the societal implications of the ecological effects in terms that are understandable and useful to planners and decision-makers. The purpose of this study is to develop a basic framework for assessing the societal implications of the river ecological effects expected of a proposed large dam project. The aim is to facilitate a comparison of desired and potential undesired effects on-site and downstream. The study involves two main tasks: to identify key river goods and services that a river system may provide, and to analyze how the implementation of a large dam project may alter the on-site capacity and downstream potentials to derive river goods and services from the river system. Three river goods and six river services are identified. River goods are defined as extractable partly man-made products and river services as naturally sustained processes. By four main types of flow manipulations, a large dam project improves the on-site capacity to derive desired river goods, but simultaneously threatens the provision of desirable river goods and services downstream. However, by adjusting the site, design, and operational schedule of the proposed dam project, undesirable effects on river goods and services can be minimized.  相似文献   

18.
This paper assesses the potential of selected efficient electrical appliances for avoiding power generation and for mitigation of selected air pollutants from the power sector in Pakistan from technical as well as national, utility and user perspectives. The study shows that about 14, 21 and 35% of the total CO2, SO2and NOxemissions in the business as usual (BAU) case could be avoided by the adoption of selected efficient appliances during 1997–2015 from the national perspective, while the corresponding figures from the user perspective are 12, 17 and 29%, respectively. All selected efficient appliances would be cost effective to the users if electricity prices were set at the long-run marginal cost of supply.1998 Academic Press  相似文献   

19.
Sustainability embraces socio-economic and bio-ecological dimensions or attributes. This paper presents a conceptual framework for quantifying sustainability on the basis of efficiency theory commonly used in economics. The conceptual model is implemented using Data Envelopment Analysis (DEA). Sustainability is measured for a sample of Dutch sugar beet growers. The average technical efficiency was only 50%. A positive correlation was found between technical efficiency and sustainable efficiency. Differences in efficiency among farmers were persistent within and between years. We conclude that there is considerable scope for improving the sustainability of arable farming by better management.  相似文献   

20.
Removal of cadmium from aqueous solutions using 20 species of plant leaves and combinations of these leaves have been studied. Several factors affecting the removal efficiency have been studied. The most efficient types of plant leaves for the removal of cadmium are those of styrax, plum, pomegranate and walnut. The interaction effect of the combined leaf samples on the efficiency of removal of cadmium has been found to be additive in combinations involving styrax plant leaves but seems to be antagonistic in all other combinations. The optimum experimental conditions for removal of cadmium have been found to be at pH 4.1, using high concentrations of naturally dried plant leaves, using ground leaves and to remove cadmium from agitated aqueous solutions. The percentage of metal removed at an initial cadmium concentration of 10mg/l by the most efficient types of leaves have been found to be 85% for styrax leaves, 85% for plum leaves, 80% for pomegranate leaves, 78% for walnut leaves and 77% for meddler leaves. The presence of foreign ions or complexing agents has been found to reduce the efficiency of removal of cadmium by plant leaves. About 80-85% of the cadmium in charged plant leaves has been released under the influence of changing the pH of the solution, addition of competing ions and the addition of EDTA. The results of removal of cadmium by plant leaves have been found to follow the Freundlich adsorption isotherm, first-order reaction with respect to cadmium and to have intra-pore diffusion as the rate-limiting step.  相似文献   

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