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921.
Decision makers responsible for natural resource management often complain that science delivers fragmented information that
is not useful at the scale of implementation. We offer a way of negotiating complex problems by putting forward a requisite
simplicity. A requisite simplicity attempts to discard some detail, while retaining conceptual clarity and scientific rigor,
and helps us move to a new position where we can benefit from new knowledge. We illustrate the above using three case studies:
elephant densities and vegetation change in a national park, the use of rules of thumb to support decision making in agriculture,
and the management of salt in irrigation. We identify potential requisite simplicities that can allow us to generate new understanding,
lead to action and provide opportunities for structured learning. 相似文献
922.
Accident investigation manuals are influential documents on various levels in a safety management system, and it is therefore important to appraise them in the light of what we currently know – or assume – about the nature of accidents. Investigation manuals necessarily embody or represent an accident model, i.e., a set of assumptions about how accidents happen and what the important factors are. In this paper we examine three aspects of accident investigation as described in a number of investigation manuals. Firstly, we focus on accident models and in particular the assumptions about how different factors interact to cause – or prevent – accidents, i.e., the accident “mechanisms”. Secondly, we focus on the scope in the sense of the factors (or factor domains) that are considered in the models – for instance (hu)man, technology, and organization (MTO). Thirdly, we focus on the system of investigation or the activities that together constitute an accident investigation project/process. We found that the manuals all used complex linear models. The factors considered were in general (hu)man, technology, organization, and information. The causes found during an investigation reflect the assumptions of the accident model, following the ‘What-You-Look-For-Is-What-You-Find’ or WYLFIWYF principle. The identified causes typically became specific problems to be fixed during an implementation of solutions. This follows what can be called ‘What-You-Find-Is-What-You-Fix’ or WYFIWYF principle. 相似文献
923.
事故调查分析方法与技术述评 总被引:1,自引:0,他引:1
根据事故的原因结果模型、过程模型、能量模型、逻辑树模型、SHE管理模型将事故调查分析技术方法归纳为5大类,介绍了广泛使用的事故调查分析技术方法的特点,并按一定的标准进行分析和比较。分析表明:每种方法都有其不同的应用领域和优缺点,应针对不同领域问题选用合适的分析方法,多种调查技术组合分析适用于复杂事故的调查;考虑事件次序及其影响因素的调查方法,便于提出预防事故再次发生和减少风险的建议,图表阐述有利于鉴别信息缺陷,并使调查组之间的沟通有力;笔者在调查过程中注重于非正常分析方法得出的结果,宜采用更为先进的事故分析技术方法以保证事故调查的客观性。 相似文献
924.
采用Claassen的养分吸收机理模型探讨了玉米与大豆幼苗磷吸收过程中的参数敏感性,结果表明:在一般土壤与施肥条件下,玉米与大豆幼苗吸收磷的高度敏感性参数或重要限制因素为根系伸长速率与根半径;在相同土壤供磷条件下,供试大豆幼苗根系的磷摄取能力远低于玉米幼苗根系的磷摄取能力,其原因归结于两者在根系最大养分流Imax与根系伸长速率K两个敏感性参数上的差异;玉米与大豆幼苗磷吸收过程中三种根毛参数的敏感性均较低,这主要与土壤供磷水平较高有关;土壤含水量在玉米幼苗磷吸收过程中表现了极高的敏感性,当土壤含水量降低时,土壤养分供应参数对玉米幼苗磷吸收的敏感性与限制作用均增大。 相似文献
925.
Marcelo Enrique Conti Domenico Cucina Mauro Mecozzi 《Environmental Modeling and Assessment》2008,13(4):553-565
A regression model is proposed for studying the relationship between trace metals concentrations and weights of individuals
of Monodonta turbinata (Born), a gastropod mollusc used as a trace metal biomonitor of marine coastal areas. The model herein presented was developed
including sites as reference factors and showed very good correlations. The prevision model of contamination gave good results
for this kind of pollutants, and it can be used as a tool for monitoring programmes. 相似文献
926.
通过对兵团土地利用空间格局变化分析,选择合适的土地利用政策保护生态环境。运用RS和GIS技术对兵团近10年土地利用/覆被变化及景观格局空间变化进行分析,并在此基础上运用Markov模型对未来30年土地利用变化进行预测。2000—2010年,新疆生产建设兵团景观多样性升高,连通性增强,形状愈来愈简单,景观格局整体变化不大;草地、灌丛、湿地、荒漠和冰川/永久积雪面积减少,耕地和城镇面积增加,森林保持稳定;人为干扰对土地利用结构的变化具有重要作用,土地利用强度受人为活动影响的同时受土地利用政策影响;在未来30年间耕地和城镇面积继续增加,除森林基本保持不变外其他土地利用类型均减小。兵团城镇用地与草地和耕地之间的矛盾逐渐显现,势必引起兵团生态格局的变化。因此,必须实行合适的土地利用政策保护环境。 相似文献
927.
Stefanie Hellweg Thomas B. Hofstetter Konrad Hungerbühler 《Environmental Modeling and Assessment》2001,6(4):219-235
This paper proposes a mathematical model for life-cycle inventory analysis (LCI) of waste incineration in Switzerland. In order to model conventional and new incineration technologies adequately, fundamental aspects of the different technologies relevant for the LCI are discussed. The environmental impact of these technologies strongly depends on the assessment of the long-term emissions of the solid incineration residues and is therefore related to value based decisions about the time horizon considered. The article illustrates that the choice of the landfill model has a significant influence on the results of life-cycle assessment of waste incineration. 相似文献
928.
F.S. Wang 《Environmental Modeling and Assessment》2001,6(4):249-260
The SWIM model is the first systems model in Australia that deals with integrated waste management systems. The main modelling approach adopted is simulation, which is based on both deterministic and stochastic models for collection systems.These models are described in this paper, after a number of modelling approaches are reviewed. An example of the application of the SWIM model is given, and planned extensions to the SWIM model are briefly outlined. 相似文献
929.
Extraction of Crotalaria juncea (Sunn hemp) oil from its seeds is important to study because of its proven promising clean fuel characteristics. Soxhlet-based solvent extraction with some modification has been tried to extract the oil. In a fluid-solid mass transfer system, where, solids are present as packed bed, dynamic behavior of bed can be described in terms of concentration of solute in solids/solvent-time profile. Some of the well-known semi-empirical models of adsorption dynamics are modified and applied since leaching of oil is just the reverse of the phenomenon of adsorption in porous media. Modified Bohart-Adams model (non-linear), modified Bed Depth Service Time (BDST) (linear), and modified Thomas model (non-linear forms) are applied. It is found that these models fit to the experimental result reasonably well. Results suggest that higher bed height, with proper shape (annular) of the bed, having a higher solvent velocity will work best. Comparing the error values (SSE, SAE, and ARE) in the four cases, it is very clear that the modified BDST model is the most suitable. In the light of transient study it is established that the modified Soxhlet apparatus with cylindrical and annular beds, performs best while leaching Crotalaria juncea oil from their seeds. 相似文献
930.
Evridiki Papahristou Nikolaos Bilalis 《International Journal of Sustainable Engineering》2017,10(4-5):207-214
AbstractIn this paper, coming out of a broader research project on how the digital prototype can be effectively integrated in the product development process of the clothing industry, the authors investigate the relationship between Corporate Social Responsibility (CSR) and Collective Actions on Sustainability and the environmental impact of the new model of fast and accelerating fashion. Extensive research was contacted with personal interviews and analysed primary data shows how new technology solutions like Product Lifecycle Management (PLM), 3D visualisation or 3D prototyping can work with and across supply chain partners to reduce the environmental footprint of their processes. The final phase of the paper involves the conceptualisation of a new apparel product development model, encompassing various digital tools which aim at addressing fit problems, extending the useful life of clothes and reducing the environmental impact of clothing in use through design and services. 相似文献