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511.
A Systems Based Framework to Examine The Multi-contextural Application of the Sustainability Concept
Andrew K. Manderson 《Environment, Development and Sustainability》2006,8(1):85-97
A conceptual framework is generated through systems principles to explain sustainability’s wide diversity of interpretation
and contextual application. Sustainability is reduced to a literal interpretation as the ability to sustain, and then expressed in simple systems as the ability of one system to sustain another system over time. This reinforces the importance of time in the sustainability debate, and suggests the concept can be legitimately applied
to timeframes that have absolute limits. The framework is expanded to complex systems as the changing ability of one or many systems to sustain the changing requirements of one or many systems, over time. This accommodates multiple relations and system dynamics, and hints at the extraordinary complexity encompassed by the sustainability
concept. Practical implications relate to the evolving meaning of sustainability, the need for continual change to remain
sustainable, and that the sustainability concept can be validly applied to virtually any context or situation that exhibits
a dimension of continuity. Derived criteria useful for clarifying contextual applications of sustainability include stating
the how, what, why, who and for how long of sustainability, along with indicating the most appropriate hierarchical tier at which the concept is being applied. 相似文献
512.
建立与实施环境和职业健康安全管理整合体系有利于企业降低管理成本、提高管理效益。环境管理体系标准的改版加强了其与其他管理体系之间的协调性和兼容性,有利于进一步推动整合体系的建立与实施。在深入研究GB/T24001-2004版标准在结构框架、术语、要素名称及内容等方面变化情况的基础上,在环境和职业健康安全方针、目标、指标和方案的策划、资源,特别是基础设施的保障、合规性评价的完善、纠正措施和预防措施的实施以及一体化内部审核的开展等方面提出了建议对策,以供企业借鉴。改进环境和职业健康安全管理整合体系,以适应体系标准的发展变化,不断提高企业的现代安全健康管理水平是企业可持续发展的重要因素。 相似文献
513.
The Indo-Gangetic plain (IGP; including regions of Pakistan, India, Nepal, and Bangladesh) is generally characterised by fertile soils, favourable climate and an abundant supply of water. Nevertheless, the challenge of increasing food production in the IGP in line with demand grows ever greater; any perturbation in agriculture will considerably affect the food systems of the region and increase the vulnerability of the resource-poor population. Increasing regional production is already complicated by increasing competition for land resources by non-agricultural sectors and by the deterioration of agri-environments and water resources. Global environmental change (GEC), especially changes in climate mean values and variability, will further complicate the agricultural situation and will therefore, have serious implications for food systems of the region. Strategies to reduce the vulnerability of the region's food systems to GEC need to be based on a combination of technical and policy options, and developed in recognition of the concurrent changes in socioeconomic stresses. Adaptation options need to be assessed with regard to their socioeconomic and environmental efficacy, but a greater understanding of the interactions of food systems with GEC is needed to be able to do this with confidence. This paper discusses information needs relating to resource management and policy support to guide the development of research planning for increasing the robustness of IGP food systems to GEC. Further information is needed to develop a range of adaptation strategies including augmenting production and its sustainability, increasing income from agricultural enterprises, diversification from rice–wheat systems, improving land use and natural resource management, and instigating more flexible policies and institutions. 相似文献
514.
515.
This article reviews attempts by other workers to derive full economic evaluations of local authority waste paper recovery operations and proposals from government bodies to devise uniform costing systems for these schemes. In the light of this work a standard costing system for local authority waste paper recovery operations is proposed. Empirical data was obtained from a number of local authorities and analysed using this standard costing system. The viability of each scheme under the standard costing system and the Council's original costing system is compared. 相似文献
516.
基于遗传模拟退火算法的频率指配算法研究 总被引:2,自引:0,他引:2
在复杂电磁环境中进行频率指配是频谱管理中极为重要且困难的研究课题。提出了一种基于遗传模拟退火算法的频率指配算法,以基本遗传算法为基础,采用自适应的交叉概率和变异概率,将遗传操作和模拟退火操作相结合,从而克服了一般遗传算法的不足,可有效避免陷入局部最优并最终趋于全局优化。理论分析和仿真结果表明,该算法能够给整个无线电网络合理地指配频率,同时能有效地控制算法自身的收敛速度,与传统的指配算法相比,新算法在指配效果上有了很大的提高。 相似文献
517.
钙钛矿CaFeO_3光催化降解大红染料废水性能的研究 总被引:1,自引:0,他引:1
用柠檬酸络合法制备钙钛矿型复合氧化物CaFeO3,并以其为光催化剂对水溶性染料进行光催化降解实验。讨论了光催化反应时间、催化剂投加量、光照强度、pH值、以及外加氧化剂(H2O2)等因素对光催化活性的影响。实验结果表明:在催化剂投加量0.4g,降解时间180min,pH值2,光照强度200W,H2O2的投加量5mL时,大红染料的降解率可达99.83%。 相似文献
518.
An adaptive neuro fuzzy inference system was used for classifying water quality status of river. It applied several physical and
inorganic chemical indicators including dissolved oxygen, chemical oxygen demand, and ammonia-nitrogen. A data set (nine weeks,
total 845 observations) was collected from 100 monitoring stations in all major river basins in China and used for training and validating
the model. Up to 89.59% of the data could be correctly classified using this model. Such performance was more competitive when
compared with artificial neural networks. It is applicable in evaluation and classification of water quality status. 相似文献
519.
Upasna Sharma Anand Patwardhan 《Mitigation and Adaptation Strategies for Global Change》2008,13(8):819-831
Differences in impacts of climate hazards across exposed units are determined by many factors including the severity of the
hazard itself, the population that is exposed to the hazard and the coping capacity of the exposed units to the hazard. Coping
capacity or adaptive capacity results from a combination of development status (generic capacity) and interventions pertinent
to the hazard (specific capacity). This paper explores the extent to which the generic adaptive capacity may explain the variation
in tropical cyclone impacts. Therefore this paper offers an empirical approach by which adaptive capacity may be measured
and validated against actual outcomes. Results not only validate the role of generic adaptive capacity in explaining variations
in impact but also reveal that general development indicators are not very important as far as predicting outcomes is concerned.
Those indicators of development that can be linked to the impact process are significant in explaining and predicting impact.
This can help identify those aspects of generic adaptive capacity which are important from the perspective of policy action
for enhancing adaptive capacity to a particular climate hazard.
相似文献
Anand PatwardhanEmail: |
520.
Most colonial pinnipeds form extreme clusters of breeding females that cannot be entirely explained by the distribution of sites for reproduction. Avoidance of male harassment has been postulated as an important determinant of reproductive aggregation in this group of mammals. Female gregariousness can reduce harassment by resident males by two mechanisms; directly by the 'dilution effect' or indirectly because resident males that defend large female groups are less harassing. In order to investigate the relationship between male harassment and female gregariousness in relation to the size of breeding groups, we analysed the behaviour of dominant males and their females in a breeding colony of Otaria flavescens. Females in large breeding groups received less harassment by resident males due to dilution effects and because males that defended a large group interacted less frequently with females than males with small groups. 相似文献