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1.
组合优化的能源消费量预测模型   总被引:1,自引:0,他引:1  
田峻山  俞奇勇  张帆 《资源开发与市场》2007,23(10):893-895,954
针对非等间距灰色系统预测中存在误差较大的问题,结合序列本身的特点,利用世界能源消费的历史数据,采用3种灰色预测模型与神经网络进行组合优化,建立了灰色神经网络的能源消费量组合预测模型。实证分析结果表明,提高了模型的拟合和预测精度,拓宽了应用范围。该模型可对能源的消费趋势进行预测,为科学分析能源结构提供依据。  相似文献   

2.
灰色系统方法在城市生活垃圾量预测中的应用   总被引:2,自引:0,他引:2  
利用灰色关联分析方法分析了影响城市生活垃圾量的因素,建立了生活垃圾量的GM(1,1)预测模型,预测了未来的城市生活垃圾量。该法具有较高的精度,简便,可行。  相似文献   

3.
This paper discusses how world steel production and seaborne iron ore trade have grown since 1950. The role of steel production forecasts in determining investment in the iron ore industry is examined. Forecasts for world steel production and the demand and supply of seaborne iron ore in the 1990s are presented. It is predicted that world steel production will increase by 64 million tons between 1991 and 2000. This increase will be located principally in the developing countries and China. The corresponding increase in seaborne iron ore trade will be approximately 55 million tons. Expansion projects will be located mainly in Australia and Brazil, but no greenfield iron ore projects will be undertaken. By the end of the decade, the demand for seaborne iron ore will be equal to its supply.  相似文献   

4.
The magnitude of the ‘economic rent’ and its distribution among producing countries, mineral exploitation companies and consumers has become a dominant issue in national and international policy formulation, but the difficulties in measuring the rent add to the problems of determining its equitable distribution. This paper examines the nature of the rent and estimates its incidence in bauxite, copper, iron ore, phosphate rock, tin and petroleum. Rents were found to be low for bauxite and iron ore. Bauxite, phosphates and petroleum producers have increased their share of the rent, though this trend now seems to be reversing for bauxite and phosphates. Only in tin, and to a lesser extent petroleum, have the exporting countries captured significant shares in total rent. Otherwise, the rent is largely concentrated at the processing stage, which suggests that processing plant would have to shift to the producing countries if they are to claim a larger share.  相似文献   

5.
Japan is the world's largest steel producing country, and around half of its total input requirements for coking coal and iron ore are sourced from Australia. Moreover, around half of Australia's total coking coal and iron ore exports go to Japan each year. Therefore, changes in the demand for these two inputs are likely to have a significant impact on Australia. The purpose of this paper is to investigate the production structure of the blast furnaces in Japan and factors affecting the demand for iron making raw materials. The empirical study is based on the generalized Leontief cost function. Because of its functional flexibility, the model allows testing various hypotheses regarding pig iron production from blast furnaces. Based on the data from 1974 to 1991, the modelling results show that the Japanese ironmaking technology, when considered as an aggregate production process using fuel and iron ore as major inputs, could be characterized by fixed factor proportions, constant returns to scale and technical changes that can be explained by systematic changes in input mix. Moreover, while there is little variation in the iron ore usage rate, variations in fuel usage rate can be explained largely by changes in the make-up of iron ore charge and blast furnace production capacity over the sample period.  相似文献   

6.
以1997-2012年《中国林业统计年鉴》的全国森林火灾成灾面积为依据,应用BP神经网络模型对成灾面积进行了预测,对预测方法进行了检验.在此基础上,利用残差提出了修正的BP神经网络模型,并对预测方法进行了改进.研究结果表明,修正的BP神经网络预测精度高于BP神经网络,预测相对误差平均为7.2%,可应用于森林火灾成灾面积的预测.  相似文献   

7.
This paper examines the profile of the global mining equipment supply industry, looking at the largest producers and consumers of mining equipment, tracking the changes in global flows of such equipment over the past decade. This paper shows that while the conventional producers of mining equipment (United States, Germany and Japan) have increased exports over the mining boom, the greater gain has been made by countries in the South (particularly China). The destination market for mining equipment has also begun to change, increasingly moving towards new mining sites (in Africa, East Asia and Latin America) and away from the traditional mining countries (Europe and North America). In SSA, China increasingly accounts for a rapidly growing share of mining equipment imports, but this trend is associated with the general increase in imports from China rather than China's resource specific engagement with SSA.  相似文献   

8.
ABSTRACT

Time-series and machine-learning methods are being strongly exploited to improve the accuracy of short-term load forecasting (STLF) results. In developing countries, power consumption behaviors could be suddenly changed by different customers, e.g. industrial customers, residential customers, so the load-demand dataset is often unstable. Therefore, reliability assessment of the load-demand dataset is obviously necessary for STLF models. Hence, this paper proposes a novel and unified statistical data-filtering method with the best confidence interval to eliminate unexpected noises/outliers of the input dataset before performing various short-term load forecasting models. This proposed novel data-filtering method, so-called the data pre-processing method, is also compared to other existing data-filtering methods (e.g. Kalman filter, Density-Based Spatial Clustering of Applications with Noise, Wavelet transform, and Singular Spectrum Analysis). By using an SCADA system?-based database of a typical 22kV distribution network in Vietnam, NYISO database, and PJM-RTO database, case studies of short-term load forecasting have been conducted with a conventional ARIMA model, an ANN forecasting model, an LSTM-RNN model, an LSTM-CNN combined model, a deep auto-encoder (DAE) network, a Wavenet-based model, a Wavenet and LSTM hybrid model, and a Wavelet Neural Network (WNN) model, which are to validate the novel and unified statistical data-filtering method proposed. The achieved numerical results demonstrate which the accuracy of the aforementioned STLF models can be significantly improved due to the proposed statistical data-filtering method with the best confidence interval of the input load dataset. The proposed statistical data-filtering method can considerably outperform the existing data-filtering methods.  相似文献   

9.
Silver (Ag) is a precious metal of increasing importance. Besides its classical use as a valuable, it is applied in an increasing number of industrial products due to its advantageous chemical properties. As silver is considered a non-renewable resource, it is becoming more and more relevant for individual countries to gain a better understanding of their domestic silver material flows. In our study, a material flow analysis (MFA) of silver in Austria for the period 2012 was carried out, the results of which reveal the major silver flows in the country as well as the imports and exports outside the country. As there is no extraction of silver ore in Austria, the country is depending on silver imports and recycling. Furthermore, the role of the silver coin production that is of considerable importance in Austria is highlighted. The results may help, on a policy level, to determine silver use indicators and support the development of strategies for resource, waste and environmental management of silver. On a modeling level, the results may function as an example for future silver MFA studies in different countries.  相似文献   

10.
青龙县部分铁矿企业的无序开采给水土保持、生态环境带来了严重危害。落实科学发展观,以生态科学为指导,建设资源节约型、环境友好型的铁矿开采企业迫在眉睫。为此提出以下防治对策:加大执法力度,加强对铁矿企业的监管;编报水土保持方案,严格审批服务;因地制宜,采取水土保持措施;强化铁矿企业生态环境保护,推广尾矿综合利用。  相似文献   

11.
我国是世界上13个贫水国之一,水资源紧缺的问题在一些地区已制约经济和社会的发展。中水主要是指城市污水或生活污水经处理后达到一定的水质标准,可在一定的范围内重复使用的非饮用杂用水。中水的水质介于上水和下水之间,是水资源有效利用的一种形式。开展中水回收工作,已经显现出开源和减轻水污染的双重功能。  相似文献   

12.
To examine the impact of the change in forward pricing mechanism on the volatility of iron ore spot prices, we model the iron ore daily price of Platts IODEX from October 7, 2008 to September 21, 2012. The identified iron ore spot price tends to be less volatile after the introduction of quarterly pricing mechanism. Our main approaches are as follows: (i) to decompose the spot price of Platts IODEX into two subsamples and relate the result of the structural break to the date of the switch in the iron ore forward pricing mechanism; (ii) to apply the EGARCH (1, 1) model to simultaneously capture the long memory and the asymmetric effect on the volatility of the iron ore spot price; and (iii) to delineate the news impact curve to further interpret the asymmetric effect.  相似文献   

13.
The paper studies and applies the approaches to forecast long-term (LT) real prices of iron ore. This price is crucial for valuation of investments in Greenfield iron ore projects on the horizon of more than 5 years. The forecast is obtained by three different approaches which are usually used by investment bank analysts: marginal costs approach and 2 approaches based on calculation of incentive price. The paper concludes that there has been a structural shift on the iron ore market and LT iron ore prices will be higher by 20–30% than the average of industry forecasters suggest. This is related to the 2 key factors which were taken into account in this study—depletion of existing iron ore deposits and targeted return on investments for new projects. In addition, escalated industry costs inflation is claimed to be the factor which will bolster nominal iron ore prices at high levels in the long-term. Using a Monte-Carlo simulation approach, confidence interval for future iron ore price was estimated.  相似文献   

14.
China     
For the first time since the mid-1960s, China became a net oil importer in 1993. That the country will remain a net oil importer is inevitable and probably irreversible for the foreseeable future. In the period to 2000, its crude oil production is projected to increase only 2% annually, while demand for refined oil products is expected to grow at 6.6% per annum. As a result, China's net oil imports are expected to reach 1.3 million barrels per day in 2000, accounting for almost one-third of its projected oil consumption. Most of the imports will come from the Middle East, and China's dependence on Middle Eastern oil is expected to increase significantly in the future .  相似文献   

15.
China has embarked on major economic and social changes to revitalize the Chinese economy, increase labor productivity, and improve the material standard of living of the Chinese people. This paper assumes that China will achieve its goal of a per capita income of US$800 in 2000, open-door policies will be maintained, and nonfuel mineral commodity consumption will increase as GDP per capita increases. Projections are made of production, trade and consumption of 14 nonfuel minerals for the period 1985–2005. China is projected to increase its net imports to these 14 minerals from about US$5000 million in 1985 to about US$12000 million in constant dollars in 2005. China's investment climate will become more favorable for those multinational companies that bring with them clear comparative advantages in minerals exploration, mining and processing technologies and marketing, and are prepared to develop in-depth Chinese expertise.  相似文献   

16.
Qiang Ye   《Resources Policy》2008,33(2):83
Western Australia is a resource-rich province. Since the 1890s, resources booms have played a key role in the development of the state's economy. In the last few years, Western Australia's resources industry has continued to enjoy exceptional conditions created by strong international demand for commodities. This paper aims to examine the likely impact of this commodity boom in the iron ore sector on the Western Australian economy, using a general equilibrium approach. The modeling results indicate that the Western Australian economy will benefit from the expansion in iron ore exports and investment in terms of rising consumption and employment, although at the industry level there will be losers as well as winners.  相似文献   

17.
2035年美丽中国建设目标及路径机制研究   总被引:3,自引:3,他引:0  
建设美丽中国,建设人与自然和谐共生的现代化,是中国特色社会主义现代化建设的重要基础与主要内容。本文通过文献分析、对标分析、模型预测等方法,识别了美丽中国建设的科学内涵及特征要求,分析美丽中国建设中长期面临的形势,基于到2035年达到中等发达国家水平、人均GDP翻一番的目标,对标发达国家以及浙江、广东等国内先进地区,构建了美丽中国建设的目标指标体系框架,并从绿色发展、气候变化、生态环境质量、环境治理体系与治理能力等方面,设计美丽中国建设生态环境保护的总体框架与主要路径,提出美丽中国建设的规划建议。  相似文献   

18.
Can China control the side effects of motor vehicle growth?   总被引:2,自引:0,他引:2  
Motor vehicle growth in China is the fastest in the world. This is placing great strain on the urban environment and causing a rapid increase in oil imports and motor vehicle carbon dioxide emissions. To deal with the environmental and health effects of air pollution, China has adopted a strong motor vehicle pollution control programme and imposed limits on fuel consumption of new light duty vehicles. The article will review these problems and programmes. Special focus will be given to the need to reduce sulphur levels in both gasoline and diesel fuel.  相似文献   

19.
The impact of consumption of renewable energy on CO2 emissions was investigated, in five MERCOSUR’s countries from 1980 to 2014. The autoregressive distributed lag (ARDL) in the form of Unrestricted Error Correction Model to decompose the total effect of variables into it is the short- and long-run components. The results of preliminary tests showed the presence of cross-sectional dependence between the variables, the stationarity of all variables in the first differences, and the homogeneity in panel data. Moreover, the specification tests pointed to the presence of cross-sectional dependence, non-correlation between the crosses, serial correlation in the panel data model, and the existence of heteroskedasticity. The results of semi-elasticities (short run) and elasticities (long run) of ARDL model pointed that the economic growth and consumption of fossil fuels increase the CO2 emissions in the short and long run, while the consumption of renewable energy reduces them. Despite the consumption of renewable energy reducing the environmental degradation in the MERCOSUR countries, its impact is small. Finally, this study proved that the consumption of renewable energy is able to reduce the CO2 emissions, which is responsible for the environmental degradation in the MERCOSUR countries, and that the economic growth of these same countries increases the CO2 emissions, along with the fact that all MERCOSUR countries are highly dependent of fossil fuels.  相似文献   

20.
The increasing construction and demolition (C&D) waste causes both cost inefficiency and environmental pollution. Many countries have developed regulations to minimize C&D waste. Implementation of these regulations requires an understanding of the magnitude and material composition of waste stream. Construction waste generation index is a useful tool for estimating the amount of construction waste and can be used as a benchmark to enhance the sustainable performance of construction industry. This paper presents a model for quantifying waste generation per gross floor area (WGA) based on mass balance principle for building construction in China. WGAs for major types of material are estimated using purchased amount of major materials and their material waste rate (MWR). The WGA for minor quantities of materials is estimated together as a percentage of total construction waste. The model is applied to a newly constructed residential building in Shenzhen city of South China. The WGA of this project is 40.7 kg/m2, and concrete waste is the largest contributor to the index. Comparisons with transportation records in site, empirical index in China and data in other economies reveal that the proposed model is valid and practical. The proposed model can be used to setup a benchmark WGA for Chinese construction industry by carrying out large-scale investigations in the future.  相似文献   

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