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1.
A.D. Owen 《Resources Policy》1983,9(2):110-121
The major characteristics of the demand for uranium are identified, and a number of factors which determine the actual level of uranium requirements of the nuclear power industry are discussed. Since the role of inventories is central to the process of short-term price formation, by comparing projections of uranium production and apparent consumption, the relative level of total inventories is calculated and an assessment is made of its likely impact on the uranium market during the 1980s. 相似文献
2.
Western mine production of gold has been declining in the past five years — at the same time as the price of gold has risen dramatically. Predictions of a continued high demand for gold and the current US interest in adopting some form of ‘gold standard’ have focused attention on the supply of new gold. This paper discusses the structure of gold supply and demand, the present pattern of production of new gold and the possible effect of future price changes on Western gold mine production in the 1980s. 相似文献
3.
C. Suan Tan 《Resources Policy》1977,3(4):281-291
This paper presents a predictive model for the world tungsten economy, disregarding short-term speculative activity. The study provides a framework for exploring investment and optimal pricing policies and stabilizing mechanisms. The author discusses the rationale for the formulation of the structural equations, and presents estimates of a simultaneous equation model purporting to explain the structure of the tungsten ore economy. Both ex post and ex ante simulations testify to the model's predictive ability. 相似文献
4.
Robert G. Skinner 《Natural resources forum》1993,17(3):181-190
Non-OECD countries will account for the greatest share of growth in future energy demand. Policy-makers, in response to public concern that the continued use of fossil-fuels could bring about global climate change have sought out policies which will reduce future energy demand. However, economic instruments which can do so, such as carbon taxes, provoke significant distributional and equity issues. Most OECD governments have set CO2 reduction targets, but few of those targets are backed up by effective legislation and programmes. Instead, most governments seem to count on increasing energy efficiency, seemingly 'spontaneously', to bring about CO2 reductions. Realization of OECD CO2 reduction targets would be insignificant on a global scale, but they are nevertheless very ambitious when compared to recent changes in the OECD's energy-derived CO2 emissions. Reliance on market forces alone may therefore not be enough. 相似文献
5.
Irrigation pricing policies and its impact on agricultural inputs demand in Tunisia: a DEA-based methodology 总被引:1,自引:0,他引:1
Frija A Wossink A Buysse J Speelman S Van Huylenbroeck G 《Journal of environmental management》2011,92(9):2109-2118
This paper estimates farmers' individual irrigation water demand functions employing the information hidden in individual farmers' technical efficiency. This information is extracted through the development of a new deductive methodology based on inverse Data Envelopment Analysis (DEA) models. The empirical results for Tunisia show that farmers who are more technically efficient have less elastic irrigation water demand functions; these farmers would adjust demand only to a limited extent and they can afford the water price. In contrast, water pricing significantly affects those that are less efficient. These farmers shift towards a different cropping pattern using significantly less water and more land when the price of water increases. Thus, higher water prices would threaten this category's livelihood if their efficiency is not improved. However, if the technical efficiency of these farmers were to improve, then it would be more difficult to reach water saving objectives since their demand will also become highly inelastic. The findings have important implications in view of the objectives of Tunisia water policy which include:full cost recovery, continuity of the irrigation activity, and water saving at the national level. 相似文献
6.
This paper investigates the scope for stabilizing commodity prices by buffer stock interventions. Optimal control is used, rather than simulation, to evaluate the scope for intervention at best. Applications to a world copper market model show that substantial but extensive gains to stabilization are possible. These gains cannot be realised by traditional bandwidth decision rules. An important difficulty is setting the level at which prices should be stabilized. The lack of this information severely reduces the achievable gains. 相似文献
7.
There is no place like England to witness the role of pubs as a social networking hotspot. Social networks lie at the foundations of most of the social and economic interactions of individuals. The aim of this paper is to assess the importance of pubs as natural locations for the development of social networks and how their presence affects the socio-economic activity of a given area or region. The econometric analysis conducted on rural parishes in Cumbria, a peripheral county in Northern England, reveals that village pubs have a positive influence on the socio-economic activity of local communities. 相似文献
8.
Stephen Wright 《Resources Policy》1977,3(4):261-267
This paper argues that there has been insufficient analysis of long-term forecasting methods for resource demand at national level, compared with the attention devoted to supply factors. It suggests several important issues which need to be understood about the nature of demand projection and its pitfalls. Some significant and widely used resource demand models are summarized, all of which are particularly vulnerable to the uncertainty of macroeconomic modelling. 相似文献
9.
Byeong Gyu Gang 《International Journal of Green Energy》2016,13(12):1224-1231
Constant hydrogen generation via a hydrogen generator is evaluated from the methanolysis of sodium borohydride (NaBH4) using Co/Al2O3 and MnOx/Al2O3 catalysts. Chemical borohydrides coupled with catalysts can be used for compact storage and to create efficient generation systems. Thus, we first report the catalytic activity of MnOx/Al2O3, which is synthesized using the simple wet-impregnation method, for the methanolysis reaction. The results indicate that both catalysts can effectively accelerate the methanolysis reaction and provide constant hydrogen generation rates. Thus, we integrate this hydrogen generation system into a proton exchange membrane fuel cell stack (PEMFC) to determine whether it can be used as a portable power supply. As a result, this fuel cell system operates at 40 W for 1 hr using the hydrogen source supplied from the catalytic methanolysis reaction. 相似文献
10.
An alternative method of estimating relative demand among nonconsumptive uses of wildlife and among wildlife species is proposed. A demand intensity score (DIS), derived from the relative extent of an individual's involvement in outdoor recreation and conservation activities, is used as a weighting device to adjust the importance of preference rankings for wildlife uses and wildlife species relative to other members of a survey population. These adjusted preference rankings were considered to reflect relative demand levels (RDLs) for wildlife uses and for species by the survey population. This technique may be useful where it is not possible or desirable to estimate demand using traditional economic means. In one of the findings from a survey of municipal conservation commission members in Massachusetts, presented as an illustration of this methodology, poisonous snakes were ranked third in preference among five groups of reptiles. The relative demand level for poisonous snakes, however, was last among the five groups. 相似文献
11.
David E. Hojman 《Resources Policy》1984,10(3):177-189
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
12.
Hesseln H Loomis JB González-Cabán A Alexander S 《Journal of environmental management》2003,69(4):359-368
We use a travel cost model to test the effects of wild and prescribed fire on visitation by hikers and mountain bikers in New Mexico. Our results indicate that net benefits for mountain bikers is $150 per trip and that they take an average of 6.2 trips per year. Hikers take 2.8 trips per year with individual net benefits per trip of $130. Both hikers' and mountain bikers' demand functions react adversely to prescribed burning. Net benefits for both groups fall as areas recover from prescribed burns. Because both visitation and annual recreation benefits decrease to these two types of visitors, this gives rise to multiple use costs associated with prescribed burning. With respect to wildfire, hikers and mountain bikers both exhibit decreased visitation as areas recover from wildfires, however, only hikers indicate an increase in per trip net benefits. Bikers' demand effectively drops to zero. These results differ from previous findings in the literature and have implications for efficient implementation of the National Fire Plan and whether prescribed burning is a cost effective tool for multiple use management of National Forests. Specifically, that fire and recreation managers cannot expect recreation users to react similarly to fire across recreation activities, or different geographic regions. What is cost effective in one region may not be so in another. 相似文献
13.
Sümer Gülez 《Environmental management》1996,20(1):113-122
The study consists of two parts. One part deals with recreation and vacation demands; the other investigates the relationship
between recreation demand and some natural landscape elements preferred in the eastern Black Sea coastal zone of Turkey, which
has traditionally a rich recreational culture. Home interview surveys were conducted during the summer of 1992. The recreation
demand of the study area has been found to be 89.3% including potential demand. The landscape element "sea and seaside" preferred
for recreation has been rated the highest in all groups of each of the five variables, namely, age, education, income, occupation,
and marital status. The research reported here represents an empirical contribution to the field of landscape preference studies
for recreation, especially in the developing countries. 相似文献
14.
F. Roberts 《Resources Policy》1977,3(1):13-22
As national economies grow, requirements for physical resources increase. This paper attempts to forecast future world demand for lead, by deriving a relationship between the amount consumed per capita and the level of economic development, and then using this to generate world demand figures based on some predictions of future economic growth. Although the rate of increase in demand for lead may decline as high levels of GDP are reached, it is nevertheless predicted that world annual demand could continue rising exponentially over the next 50 or 60 years, in the absence of constraints due to lack of physical resources or very high differential prices. This is essentially because large areas of the world will still be increasing their GDP per capita over the range where the rate of increase in demand for lead is increasing steeply. 相似文献
15.
David Humphreys 《Resources Policy》1982,8(3):215-229
The production, price and economic resources profiles of a number of mineral commodities are examined and consideration is given to the theory that such profiles can be related to one another within the framework of a life-cycle model of development. While the behaviour of some of the commodities examined appears to lend support to the theory, that of others reveals fundamental problems with its underlying assumptions. It is concluded that, while the demand for a mineral commodity in specific uses may indeed manifest cyclical tendencies, as a general behavioural theory and as a basis for resource estimation the life-cycle model applied to minerals is of little value. 相似文献
16.
Solid waste poses a serious problem to government agencies and people in third world cities. Recycling as a way of managing waste has received relatively little attention. This paper examines the role of waste scavengers in the waste recycling process. The preliminary findings reported here indicate that the waste scavenger could be incorporated formally into the recycling process. Using plastic waste as an example, it is demonstrated that such recycling is economically viable. 相似文献
17.
In a recent article (Tilton, Humphreys, and Radetzki, 2011), Tilton et al. argue that even when investor stocks are declining an increase in investor demand can cause a commodity's price to rise. They contend that this conclusion, which is based on two hypothetical examples, is both contrary to conventional wisdom and counter-intuitive. In my comment on the article (Olle Östensson, 2011), I challenged this finding. In a reply to my article, Tilton et al. maintain that their original finding is valid: investor demand can be driving commodity prices higher even when stocks are falling. In my present reply, I contend that their argument with respect to the first example confuses the actions of a minority of investors with those of all investors and is well accommodated within the framework of traditional theory. I further argue that their second example rests on an assumption regarding investor behavior that is unproven and that in any case falls outside the framework of analysis of futures markets. 相似文献
18.
In a recent article (Tilton et al., 2011), we argue that even when investor stocks are declining an increase in investor demand can cause a commodity's price to rise, a conclusion that is both contrary to conventional wisdom and counter-intuitive. In his comment on our article, Olle Östensson (2011) challenges this finding. After assessing his concerns in this reply, we maintain that our original finding is valid: investor demand can be driving commodity prices higher even when investor stocks are falling. 相似文献
19.
20.
Approximately 40% of annual demand for steel worldwide is used to replace products that have failed. With this percentage set to rise, extending the lifespan of steel in products presents a significant opportunity to reduce demand and thus decrease carbon dioxide emissions from steel production.This article presents a new, simplified framework with which to analyse product failure. When applied to the products that dominate steel use, this framework reveals that they are often replaced because a component/sub-assembly becomes degraded, inferior, unsuitable or worthless. In light of this, four products, which are representative of high steel content products in general, are analysed at the component level, determining steel mass and cost profiles over the lifespan of each product. The results show that the majority of the steel components are underexploited – still functioning when the product is discarded; in particular, the potential lifespan of the steel-rich structure is typically much greater than its actual lifespan. Twelve case studies, in which product or component life has been increased, are then presented. The resulting evidence is used to tailor life-extension strategies to each reason for product failure and to identify the economic motivations for implementing these strategies. The results suggest that a product template in which the long-lived structure accounts for a relatively high share of costs while short-lived components can be easily replaced (offering profit to the producer and enhanced utility to owners) encourages product life extension. 相似文献