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811.
采用CuCl2对循环流化床锅炉飞灰进行改性,在固定床反应器上对CuCl2改性飞灰进行了气相零价汞(Hg0)吸附实验。考察了CuCl2负载量和吸附温度对改性飞灰Hg0吸附能力的影响,并结合颗粒内扩散模型、准一阶动力学模型、准二阶动力学模型和耶洛维奇模型拟合结果分析该过程的控制步骤。结果表明: CuCl2改性飞灰的Hg0穿透时间远大于未改性飞灰,对Hg0的吸附量随CuCl2负载量的增加而增加;CuCl2改性飞灰的Hg0吸附能力随吸附温度的升高先增大后减小,150 ℃为最佳吸附温度;准二阶动力学模型的拟合值与实验值相关系数最高,且该模型初始吸附速率与实验值最为接近,即准二阶动力学模型更适合于描述CuCl2改性飞灰的Hg0吸附过程。 相似文献
812.
关于城市公共安全可持续发展理论的初步研究 总被引:14,自引:6,他引:8
针对城市公共安全的复杂性与动态性 ,创造性地将可持续发展理论应用到城市公共安全研究中 ,概述城市公共安全可持续发展系统的基本组成 ,结合实际进行系统的结构特征分析 ;运用可靠度理论 ,探讨了系统可持续发展指标的量化及其模型建立 ;以Logistic修正模型为例 ,提出了系统评价预测研究的方法论 ,共同构建城市公共安全可持续发展理论的基本框架。为城市公共安全的进一步研究提供理论依据。 相似文献
813.
基于神经网络的煤层自然发火的非线性预测 总被引:3,自引:2,他引:1
煤炭自燃是一典型的非线性现象。笔者论述了煤炭自燃的危害 ,从非线性理论的角度分析了煤炭自燃的本质特征 ;应用神经网络中BP网络这一高度非线性关系映射建立了自然发火预测模型 ,克服了传统预测方法的不足并在山东枣庄矿业集团公司柴里煤矿进行了预测分析 ,预测结果与验证结果基本吻合 ,取得了满意的效果 ,为解决煤炭自燃的预测提供了一条良好的思路和方法 ,具有较大的理论意义和应用价值。 相似文献
814.
Co-management of Natural Resources: A Proposed Framework 总被引:3,自引:1,他引:2
Co-management acknowledges pragmatic developments and progression of institutional choice theories in natural resource management. This innovative concept embraces a pluralistic management approach based on the principle of subsidiarity and creates opportunities for the reconciliation of competitive property claims. This article reviews definitions of co-management, distinguishes it from other property rights regimes, and develops an organizational structure of the major elements involved. Synthesis of both experiences and literature leads to the development of a conceptual framework. Co-management is structured in terms of context, components, and linking mechanisms. In concert, these elements offer insight into the practice of co-management, address the shortcomings of institutional theories, and respond to critical issues raised in related literature. The framework contributes to natural resource management by acting as a means of identification and evaluation for such arrangements, as well as a systematic guide for future inquiries. 相似文献
815.
A Multiattribute Index for Assessing Environmental Impacts of Regional Development Projects: A Case Study of Korea 总被引:1,自引:0,他引:1
Evaluating environmental impacts has become an increasingly vital part of environmental management. In the present study,
a methodological procedure based on multiattribute utility theory (MAUT) has been applied to obtain a decision-maker's value
index on assessment of the environmental impacts. The paper begins with an overview of MAUT. Next, we elicited strategic objectives
and several important attributes, and then structured them into a hierarchy, with the aim of structuring and quantifying the
basic values for the assessment. An environmental multiattribute index is constructed as a multiattribute utility function,
based on value judgements provided by a decision-maker at the Korean Ministry of Environment (MOE). The implications of the
results are useful for many aspects of MOE's environmental policies; identifying the strategic objectives and basic values;
facilitating communication about the organization's priorities; and recognizing decision opportunities that face decision-makers
of Korea. 相似文献
816.
区域火灾风险评估模型研究的理论与实践 总被引:18,自引:8,他引:10
首先立足于风险研究这个大背景下,在理论上对风险的概念进行了比较分析。然后针对水灾的风险根据其研究与实践中的侧重点不同,分为“损失可能性”学派、“未来损失”学派以及“损失不确定性”三个学派。在此基础上,分析了水灾风险的不确定性,从而提出了易于概率论和可能性理论的水灾风险定义,并将此定义应用于区域水灾风险评估的模型中。最后,探讨了水灾风险评估研究的问题与对其未来的展望。 相似文献
817.
This paper presents a GA-based compromise programming technique for assessing the relocation strategy of urban air quality monitoring network with respect to the multi-objective and multi-pollutant design criteria. While the impact of conservative, quasi-stable, and reactive pollutants are considered in the design principles via a simulation analysis, cost, effectiveness, and efficiency characteristics are postulated in the optimization process. Therefore, technical coverage for illustrating the needs of siting air quality monitoring stations (AQMS) includes both the air quality simulation and optimization modeling analyses in a two-stage analytical framework simultaneously. It starts from determining the spatial interrelationship among those candidate sites using various types of air quality simulation models as an integrated means. And the outputs drawn from the simulation models can then be used as the required inputs in the compromise programming model in order to screen all those siting alternatives that may satisfy the planning goals subject to the essential constraints throughout the multi-objective optimization process. For the illustrating purposes, a series of technical settings for finding the optimal relocation scenarios of AQMS were examined in the case study for the city of Kaohsiung in South Taiwan where the long-term violations of official standards of ozone and particulates turn out to be critical. It not only expresses the ideas of relocation strategy but also indicates how to utilize those alternatives in the decision-making process for improving the functionality of air quality monitoring in the urban environment. Experience gained in this study clearly indicates that the more the number of pollutants and objectives considered simultaneously, the higher the number of candidate sites to be selected in the relocation strategy. 相似文献
818.
Floris Frederik van Ogtrop Arjen Y. Hoekstra Frank van der Meulen 《Journal of the American Water Resources Association》2005,41(3):607-619
ABSTRACT: The aim of this paper is to compare two views of flood management and thus add to the present thinking of living with floods as opposed to the traditional approach of flood control. The traditional pathway has widely been adopted in developed countries and aims to control floodwaters by means of dams and dikes. The alternative pathway tends towards a policy whereby society lives with the floods by being prepared and having the right damage reduction measures in place. In this paper two pathways are tentatively compared for the Lower Incomati Basin, Mozambique. In the design cultural theory is considered, as is how the design of each path may look according to different management perspectives. The Lower Incomati Basin provides an interesting case study as it is in a relatively undeveloped state. Hence, it is an ideal area for conducting research into the application of alternative flood management strategies. The preliminary results suggest that both pathways are feasible. However, considering recent hydrological extremes such as the 2000 floods, the resilient pathway may ultimately be a more appealing flood management strategy. 相似文献
819.
820.
灰色系统理论在岩崩,滑坡监测中的应用 总被引:2,自引:0,他引:2
本文根据灰色系统理论,利用1990~1993年的GPS观测结果,建立了岩崩、滑坡的预测模型GM(1.1)。同时进行了灰色关联度分析,从而求得新滩滑坡区的地壳形变规律。由于该区地处长江三峡工程的重要地段,因此进行长期监测是非常必要的 相似文献