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1.
A new Swiss TIMES (The Integrated MARKAL–EFOM System) electricity model with an hourly representation of inter-temporal detail and a century-long model horizon has been developed to explore the TIMES framework’s suitability as a long-term electricity dispatch model. To understand the incremental insights from this hourly model, it is compared to an aggregated model with only two diurnal timeslices like in most MARKAL/TIMES models. Two scenarios have been analysed with both models to answer the following questions: Are there differences in model solutions? What are the benefits of having a high number of timeslices? Are there any computational limitations? The primary objective of this paper is to understand the differences between the solutions of the two models, rather than Swiss policy implication or potential uncertainties in input parameters and assumptions. The analysis reveals that the hourly model offers powerful insights into the electricity generation schedule. Nevertheless, the TIMES framework cannot substitute for a dispatch model because some features cannot be represented; however, the long model time horizon and integrated system approaches of TIMES provide features not available in conventional dispatch models. The methodology of the model development and insights from the model comparison are described.  相似文献   

2.
为满足《水污染防治行动计划》近岸海域水质考核要求,根据目前近岸海域环境监测工作的实际情况,在考核范围、评价方法、目标分解、计分方法等方面进行了比较,在保证公平、公正的前提下,以一致性、可比性和适应性为原则,提出的考核评价方法以单因子评价法和点位评价法为基础,在未达标情况下,按照水质目标完成比例计分;达标情况下,在达标分值基础上按水质的保持和改善给予不同程度的加分,通过实例研究分析能够适应近岸海域水质状况变化的考核工作要求。  相似文献   

3.
Marginal abatement cost (MAC) curves are a useful policy tool to communicate findings on the technological structure and the economics of CO2 emissions reduction. However, existing ways of generating MAC curves do not display consistent technological detail and do not consider system-wide interactions and uncertainty in a structured manner. This paper details a new approach to overcome the present shortcomings by using an energy system model, UK MARKAL, in combination with index decomposition analysis. In addition, this approach allows different forms of uncertainty analysis to be used in order to test the robustness of the MAC curve. For illustration purposes, a sensitivity analysis concerning fossil fuel prices is applied to the transport sector of the UK. The resulting MAC curves are found to be relatively robust to different fuel costs at higher CO2 tax levels. The new systems-based approach improves MAC curves through the avoidance of an inconsistent emissions baseline, the incorporation of system-wide interactions and the price responsiveness of demand.  相似文献   

4.
Using similarity measures in benthic impact assessments   总被引:5,自引:0,他引:5  
Eleven similarity measures were used to assess the impacts of clam digging on the infauna of one intertidal mud-flat. When the similarity matrices were clustered using a divisive polythetic algorithm two different conclusions were possible from the dendograms produced. Dendograms generated by 3 coefficients indicated digging had an impact on areas dug more than once, while the 8 others did not. In addition, existing data from an impact analysis of a power plant effluent were re-analyzed using 5 different coefficients. In this case, three of the five coefficients gave results which indicated that the benthic community at the effluent pipe was different from that present at the control. Two coefficients gave the opposite conclusion — the populations were not different.These results indicate that the objectivity of cluster analysis, as it has come to be used in impact studies, is only apparent, not real. Too many subjective choices are made in selecting algorithms and methods of interpretation. Objective criteria need to be developed for the choices made, based on the intrinsic and ecological properties of the quantitative methods. Some criteria that have been developed are discussed, and used to determine which coefficients are best suited for the two data sets analyzed. To reduce the number of subjective choices made an analysis of variance of the similarity matrix is presented as an alternative to clustering.  相似文献   

5.
A method is presented for the design of multi-pollutant air quality monitoring networks (AQMN). This technique leads to an optimal network, i.e. a network providing a maximum of information with a minimum of measurement devices. The spatial correlation analysis technique is used to compare the information given by the potential sites that may form the network. The concept of potential of violation is defined to take into account the number of times that the maximum emission values tolerated by law are exceeded. Both objectives are weighted automatically through an adjustable parameter, b, for which an estimation procedure has been developed in this study, depending on the purpose of the network. Several methods are described, allowing simultaneous consideration of different pollutants. As an illustration of these methods, a number of air quality monitoring networks is designed to perform an analysis of the environmental impact due to a hypothetical potash processing plant and two thermal power stations.  相似文献   

6.
头屯河流域在主要河道上修建2处拦河水库及多处引水工程,虽然每年不同程度,周期性向拦河控制性工程以下河段下泄河道生态水量,但是尚未分析论证下泄的河道生态水量及下泄周期是否满足全年河道生态需求。尤其在枯水季节头屯河水库下游往往干涸断流,洪水季节易发污染事故,河道生态达不到预期保护效果。河道生态基流分析计算及提出头屯河流域生态保护的保障措施已经到了非解决不可的地步,河道生态基流分析计算成果作为流域水行政主管部门提出头屯河流域生态保护的保障措施的重要技术支撑,从水资源合理利用与节约,河道两库联合调度、合理利用,维护水生态、保障河道基流量等方面进行工程、调度及制度建设。  相似文献   

7.
The empirical mode decomposition method is applied to analyze fluctuating periods and local features of the annual drought index and the drought index in the irrigation and non-irrigation periods from 1956 to 2010 in the Yinchuan irrigation district. In order to understand the uncertainty between these variables, the set pair analysis method is used to present the identity, discrepancy, and contrary of the drought index with multi-time scales. The results reveal that the annual drought index and the drought index in the irrigation and non-irrigation periods have a complex relationship which may be related to El Niño, the air–sea intersection, and the long period of solar activity. The drought index in the irrigation and non-irrigation periods presents mainly the contrary and the discrepancy; the fluctuating shapes of the annual drought index and drought index in the irrigation period are the same on their different period levels. The original annual drought index and its intrinsic mode function components have a certain connection degree; they mainly present the discrepancy.  相似文献   

8.
Tools and methods to improve current practices and quality in the healthcare building sector are necessary to support decision-making at different building life cycle phases. Furthermore, Healthcare Building Sustainability Assessment (HBSA) Methods are based on criteria organised into different levels, such as categories and indicators. These criteria highlight aspects of significant importance when designing and operating a sustainable healthcare building. To bring more objectivity to the sustainability assessments, the standardisation bodies (CEN and ISO) proposed core indicators that should be used in the evaluation of the environmental, societal and economic performances of buildings. Nevertheless, relying on state of the art analysis, it is possible to conclude that there are aspects of major importance for the operation of healthcare buildings that are not considered in the HBSA methods.Thus, the aim of this paper is to discuss the context of sustainability assessment methods in the field of healthcare buildings and to present a proposal for the incorporation of Sustainable-Effective Design (SED) criteria in a new HBSA method. The used research method is innovative since in the development of the list of sustainability criteria it considers the opinion of main healthcare buildings' stakeholders, the existing healthcare assessment methods and the ISO and CEN standardisation works in the field of the methods to assess the sustainability of construction works. As a result, the proposed method is composed of fifty-two sustainability indicators that cover the different dimensions of the sustainability concept to support decision making during the design of a new or retrofitted healthcare building in urban areas.  相似文献   

9.
In recent decades, the rapid development of the global society and economy has brought serious environmental problems, such as air pollution, greenhouse effect, and ecosystem degradation, all of which have attracted wide attention. Simultaneously, the use of Information Communication Technology (ICT) has been on the rise since the 1980s, which stimulates the growth of the economy and has a certain degree of impact on the ecological environment. Accordingly, the scientific community's interest in assessing this impact has grown considerably, and econometric methods are widely used as evaluation tools. However, the research results are often different in different regions, periods, environmental proxies, and ICT. Some studies indicate that the development of ICT is beneficial to environmental improvement, while others state that it is not. Therefore, a comprehensive analysis of the methods, mechanisms, and relative policy suggestions of this topic is desiderated. To address this gap, this paper carries out a systematic literature review of the usage of econometric methods in the assessment of the environmental impact of ICT. Among the 472 articles retrieved from scientific literature databases, 46 met the inclusion criteria and were analyzed in detail. This study aims to provide scholars with a mental picture of the current state of scientific research, identify the factors that influence the direction of ICT's impact on the environment, and enable future researchers to use more reliable and accurate estimation methods. The methods used in selected articles were divided into two main groups (i.e., time series models and panel data models), and panel data models were further subdivided into five categories. The detailed flow of these methods is summarized, and new advanced pre-test methods and estimators are highlighted. Furthermore, the analysis also indicates that among all the countries and regions involved in the selected articles, there is a non-strict inverted U-shaped curve between the level of socio-economic development and the direction of the impact of ICT on the environment. Finally, current research challenges are discussed, and potential directions for future research on this topic are also projected.  相似文献   

10.
Interests in the determination of different arsenic species in natural waters is caused by the fact that toxic effects of arsenic are connected with its chemical forms and oxidation states. In determinations of water samples inorganic arsenate (As(III), As(V)), methylated metabolities (MMAA, DMAA) and other organic forms such as AsB, AsC, arsenosugars or arsenic containing lipids have the most importance. This article provides information about occurrence of the dominant arsenic forms in various water environments. The main factors controlling arsenic speciation in water are described. The quantification of species is difficult because the concentrations of different forms in water samples are relatively lowcompared to the detection limits of the available analytical techniques. Several hyphenated methods used in arsenic speciation analysis are described. Specific advantages and disadvantages of methods can define their application for a particular sample analysis. Insufficient selectivity and sensitivity of arsenic speciation methods cause searching for a new or modifications already existing techniques. Some aspects of improvement and modifications of the methods are highlighted.  相似文献   

11.

The selection of a best alternative method to minimize air pollution and energy consumption for mine sites is a critical task because it encompasses evaluation of different techniques. The aim of this paper is to select most suitable technology for mining system which helps in reducing air pollution and carbon footprints by implementing the multicriteria decision analysis (MCDA) method. The existing methods or frameworks in the mining sector, which have been used in the past to select the sustainable solution, are lacking aid of MCDA, and there is a need to contribute more in this field with a promising decision system. The MCDA method is applied as a probabilistic integrated approach for a mine site in Canada. The analysis involves processing inputs to the Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) method which assists in identifying the alternatives, defining the criteria, and thus outranking of the final choice. Moreover, criteria weighting has been determined using analytical hierarchical process (AHP) method. Three categories: reduction of dust/fugitive emission control strategies, reduction in fuel consumption to minimize carbon footprint, and cyanide destruction methods are selected. The probability distributions of criteria weights and output flows are defined by performing uncertainty analysis using the Monte Carlo simulation (MCS). The sensitivity analysis is conducted using Spearman’s rank correlation method and walking criteria weights. The results indicate that the integrated framework provides a reliable way of selecting air pollution control solutions and help in quantifying the impact of different criteria for the selected alternatives.

  相似文献   

12.
Many types of methods to assess land use impact have been developed. Nevertheless a systematic synthesis of all these approaches is necessary to highlight the most commonly used and most effective methods. Given the growing interest in this area of research, a review of the different methods of assessing land use impact (LUI) was performed using bibliometric analysis. One hundred eighty seven articles of agricultural and biological science, and environmental sciences were examined. According to our results, the most frequently used land use assessment methods are Life-Cycle Assessment, Material Flow Analysis/Input–Output Analysis, Environmental Impact Assessment and Ecological Footprint. Comparison of the methods allowed their specific features to be identified and to arrive at the conclusion that a combination of several methods is the best basis for a comprehensive analysis of land use impact assessment.  相似文献   

13.
Simulation models are used to aid the decision makers about water pollution control and management in river systems. However, uncertainty of model parameters affects the model predictions and hence the pollution control decision. Therefore, it often is necessary to identify the model parameters that significantly affect the model output uncertainty prior to or as a supplement to model application to water pollution control and planning problems. In this study, sensitivity analysis, as a tool for uncertainty analysis was carried out to assess the sensitivity of water quality to (a) model parameters (b) pollution abatement measures such as wastewater treatment, waste discharge and flow augmentation from upstream reservoir. In addition, sensitivity analysis for the “best practical solution” was carried out to help the decision makers in choosing an appropriate option. The Delhi stretch of the river Yamuna was considered as a case study. The QUAL2E model is used for water quality simulation. The results obtained indicate that parameters K 1 (deoxygenation constant) and K 3 (settling oxygen demand), which is the rate of biochemical decomposition of organic matter and rate of BOD removal by settling, respectively, are the most sensitive parameters for the considered river stretch. Different combinations of variations in K 1 and K 2 also revealed similar results for better understanding of inter-dependability of K 1 and K 2. Also, among the pollution abatement methods, the change (perturbation) in wastewater treatment level at primary, secondary, tertiary, and advanced has the greatest effect on the uncertainty of the simulated dissolved oxygen and biochemical oxygen demand concentrations.  相似文献   

14.
在简要回顾APEC期间的空气质量情况的基础上,从多方面较系统的分析了APEC期间北京市空气质量的变化特征,包括各项污染物浓度水平的同比分析、不同区域不同类别站点小时浓度的百分数分布及变化情况分析、污染物日变化规律变化特征分析、空气质量改善效果的空间分布特征分析、颗粒物组分变化特征分析、污染来源解析模型、数值污染模型等方法,力求从多个方面深入了解APEC控制措施对北京市污染水平、污染特征造成的影响,并利用组分、模型等方法定性定量的评估主要空气质量影响因素、不同的污染控制措施对APEC期间空气质量改善的作用及贡献。结果表明,APEC期间,北京市空气质量得到明显改善,空气质量基本处于优良级别,各项污染物浓度大幅下降,APEC污染控制期各项污染物的百分位数浓度与无控制期出现明显分离特征,污染物的日变化低浓度持续时间更长且增长更缓慢。  相似文献   

15.
The environmental impacts of various hydrogen production processes are evaluated and compared, considering several energy sources and using life cycle analysis. The results indicate that hydrogen produced by thermochemical water decomposition cycles are more environmentally benign options compared to conventional steam reforming of natural gas. The nuclear based four-step Cu–Cl cycle has the lowest global warming potential (0.559 kg CO2-eq per kg hydrogen production), mainly because it requires the lowest quantity of energy of the considered processes. The acidification potential results show that biomass gasification has the highest impact on environment, while wind based electrolysis has the lowest. The relation is also investigated between efficiency and environmental impacts.  相似文献   

16.
Environmental risk refers to the possibility of environmental pollution events caused by natural causes or human activities. Environmental risks are transmitted through environmental media and can have destructive effects on human society and the natural environment. Understanding the current status and characteristics of environmental risks can effectively prevent and control environmental risks, which is essential for establishing the safety of ecological systems. Although many scholars have studied the environmental risk characteristics of different enterprises or regional scales and proposed corresponding control methods. However, the study of environmental risk characteristics in the national scale is still insufficient, which affects the accuracy of large-scale environmental impact assessment (EIA) and is not conducive to the formulation of the large-scale environmental management system. This paper attempts to use spatial statistical methods and geographically weighted regression (GWR) models to study the temporal and spatial evolution trends of environmental events in China and the spatial correlation characteristics of influencing factors and environmental events in different regions. The research results show that the focus of China's environmental risk is continuously shifting. At present, environmental pollution incidents are concentrated in the western region, and their spatial correlation with influencing factors varies from region to region. Spatial statistical analysis can help us understand the spatial characteristics of risk and identify the interrelationships of environmental risks in different areas. Therefore, spatial statistical analysis can provide a scientific basis for macro decision-making of large regional EIA and environmental risk management. In the future, it is recommended that the focus of environmental events in different regions should be different to reduce the risk of environmental events in China.  相似文献   

17.
18.
Intervention analysis techniques are described for identifying and statistically modelling trends which may be present in water quality time series. At the exploratory data analysis stage, simple graphical and modelling methods can be employed for visually detecting and examining trends in a time series caused by one or more external interventions. For instance, a plot of a robust locally weighted regression smooth through a graph of the observations over time may reveal trends and other interesting statistical properties contained in the time series. In addition, statistical tests, such as different versions of the nonparametric Mann-Kendall test, can be used to detect the presence of trends caused by unknown or known external interventions. To characterize rigorously and estimate trends which may be known in advance or else detected using exploratory data analysis studies, different parametric methods can be utilized at the confirmatory data analysis stage. Specifically, the time series modelling approach to intervention analysis can be employed to estimate the magnitudes of the changes in the mean level of the series due to the interventions. Particular types of regression models can also be used for estimating trends, especially when there are many missing observations. To demonstrate how intervention analysis methods can be effectively used in environmental impact assessment, representative applications to water quality time series are presented.Invited Paper for Presentation at The Workshop on Statistical Methods for the Assessment of Point Source Pollution, The Canada Centre for Inland Waters, Burlington, Ontario, Canada, L7R 4A6, September 12–14, 1988.  相似文献   

19.
Marine monitoring programmes are seldom planned and realized to fulfil the requirements of the statistical methods used. The shortcomings of these methods are rarely discussed in the literature. In this work two different methods for trend analysis are applied to a real case and attention is given to the possible violation of the underlying assumptions. Long-term changes in oxygen supersaturation in the Baltic Sea are the object of the study. Linear regression and non-parametric methods are those chosen. The linear regression gave significantly increasing trends of oxygen saturation in Arkona, Eastern Gotland basin and in the Bothnian Sea, but the tested assumptions turned out to be violated. The corresponding non-parametric trend test only confirmed the increasing trend in Arkona. It is suggested that non-parametric methods, like the one used in this work, should be favoured in the future for similar types of marine environmental data.  相似文献   

20.
To compare the results from two overlapping but unpaired synoptic surveys, a method using a geographic information system is proposed. The new method uses a GIS to create (i) minimum convex polygons (MCP) enclosing each set of survey data and (ii) Voronoi tesselations assigning area weights to each datum. The pairs of MCP and Voronoi maps are overlaid to produce a mosaic of polygons each with one datum assigned from each survey. The differences between the pairs weighted by the polygon areas provides the basis for statistical testing. Area-weighted means and variances of paired differences are computed and a z-statistic measures the significance of differences for the whole intersection area. A cross-product autocorrelation statistic provides an assessment of the spatial distribution of differences. Alternate, conventional methods are compared with the new method: analysis of variance (ANOVA), analysis of covariance (ANCOVA), and contour overlays. The four methods were applied to the comparison of two macrobenthic surveys conducted in Lake Erie. Measures for five different taxa were examined. The ANOVA and ANCOVA methods found many significant differences between surveys. Both methods were judged inappropriate as sampling data are not expected to be drawn from normally-distributed populations in spatial surveys. Differences between surveys were detected but were difficult to assess using contour overlays. The new method only found a significant difference in one taxon, an expected difference as members of that taxon were absent from most sites in one survey.  相似文献   

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