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201.
In the management literature, heuristics are often conceived of as a source of systematic error, whereas logic and statistics are regarded as the sine qua non of good decision making. Yet, this view can be incorrect for decisions made under uncertainty, as opposed to risk. Research on fast and frugal heuristics shows that simple heuristics can be successful in complex, uncertain environments and also when and why this is the case. This article describes the conceptual framework of heuristics as adaptive decision strategies and connects it with the managerial literature. We review five classes of heuristics, analyze their common building blocks, and show how these are applied in managerial decision making. We conclude by highlighting some prominent opportunities for future research in the field. In the uncertain world of management, simple heuristics can lead to better and faster decisions than complex statistical procedures. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
202.
Chemical manufacturing is a long-process industry, where an end product may pass through numerous dangerous and complex steps. In such long chains of coordinated activity, accidents remain common. This study made loss-prevention recommendations for the chemical industry after conducting a review of accident reports and creating a complex network model. A human factor analysis and classification system (HFACS) was used to classify data from 109 investigation reports from the Chinese mainland (2015–2020). Levels Ⅱ and Ⅲ of the HFACS output were fed into a complex network model to generate a map of causes and chains of risk. It was shown that most accidents were directly or indirectly caused by human action, and human factors played a decisive role in occurrence, evolution, and resolution. The model used was visualized in Gephi, and the key cause nodes were identified by their topological characteristics. A modularity algorithm was used to derive the community structures and segment the network map. Crucial nodes in each community were compared with factors for each class in the HFACS model. It was also found that there was a biasing factor in the causal processes of explosive accidents and poisoning and asphyxiation accidents according to the associations classified by modularity. Risk abatement strategies were proposed for the crucial factors.  相似文献   
203.
秦皇岛市宏观环境战略及协调因子分析   总被引:2,自引:0,他引:2  
结合秦皇岛市实际,论述了宏观环境战略及协调因子,主要分两个方面:①该市的经济发展与环境是否协调,以及明确存在的主要问题;②协调经济与环境的关系,解决矛盾的协调因子。   相似文献   
204.
Micronutrient malnutrition is a major health problem in China. According to a national nutritional survey, approximately 24% of all Chinese children suffer from a serious deficiency of iron (Fe) (anemia), while over 50% show a sub-clinical level of zinc (Zn) deficiency. More than 374 million people in China suffer from goiter disease, which is related to iodine (I) deficiency, and approximately 20% of the Chinese population are affected by selenium (Se) deficiency. Micronutrient malnutrition in humans is derived from deficiencies of these elements in soils and foods. In China, approximately 40% of the total land area is deficient in Fe and Zn. Keshan and Kaschin-Beck diseases always appear in regions where the soil content of Se in low. The soil–plant system is instrumental to human nutrition and forms the basis of the “food chain” in which there is micronutrient cycling, resulting in an ecologically sound and sustainable flow of micronutrients. Soil-plant system strategies that have been adopted to improve human micronutrient nutrition mainly include: (1) exploiting micronutrient-dense crop genotypes by studying the physiology and genetics of micronutrient flow from soils to the edible parts of crops; (2) improving micronutrient bioavailability through a better knowledge of the mechanisms of the enhancers’ production and accumulation in edible parts and its regulation through soil-plant system; (3) improving our knowledge of the relationship between the content and bioavailability of micronutrients in soils and those in edible crop products for better human nutrition; (4) developing special micronutrient fertilizers and integrated nutrient management technologies for increasing both the density of the micronutrients in the edible parts of plants and their bioavailability to humans.  相似文献   
205.
Following the signing of the Second Sulphur Protocol in 1994 under the 1979 Convention on Long-range Transboundary Air Pollution, preparations are now underway for a new multi-pollutant multi-effects protocol, under the auspices of the United Nations Economic Commission for Europe (UN ECE). A number of scientific models have been used to provide policy makers involved in these preparations with sound scientific information. These include the Abatement Strategies Assessment Model (ASAM). ASAM has recently been extended to cover abatement strategies for NH3 and NOx as well as SO2, in order to address the amelioration of acidification and eutrophication in the ECE region. It is important to be able to demonstrate that the scientific information provided to policy makers is robust to uncertainties, and hence there is a need for a thorough sensitivity analysis. In this study ASAM is used to demonstrate a large degree of robustness of derived abatement strategies to uncertainties in critical loads, meteorological data and cost information. This is based on a comparison of strategies at the same overall abatement cost. Systematic changes in data are shown to influence model results more profoundly than random changes.  相似文献   
206.
我国农田农药流失现状及减控策略   总被引:1,自引:0,他引:1  
农业面源污染已经成为全球水污染的主要来源,其中具有生物毒性的农药污染物对人体健康和生态环境安全构成了严重威胁。分析了我国农田农药流失现状,指出流失的主要农药品种与用药历史和特点密切相关,水体中检出的有机氯农药主要源于早期农药残留,检出的有机磷农药和长残效除草剂部分种类目前仍在使用。提出从影响农药流失的各个环节入手,制定严密的减控策略。植物缓冲带是拦截农药流失的常用措施,可以实现对农业面源污染的可持续治理。建议实行生态功能区划,严格限制高毒农药的施用,减少化学农药施用量,规范农药喷洒器械和施药技术,从源头上控制农药流失,从而降低农业非点源污染带来的危险。  相似文献   
207.
Modelled and measured indicator species ratios of O3/NOz, O3/NOy, H2O2/HNO3, HCNO/NOy for the Lower Fraser Valley were compared with VOC-NOx-O3 sensitivity threshold values reported in previous studies. Modelled region - specific indicator ratio thresholds derived from 50% NOx and 50% VOC reduction scenarios are provided. They show strongest agreement with the H2O2/HNO3 ratio values found elsewhere. A clear transition region for the LFV from VOC to NOx sensitivity could not be identified, but there is evidence that O3 concentrations in the western valley, dominated by metropolitan Vancouver, are VOC sensitive, and the more rural eastern valley O3 concentrations exhibit greater NOx sensitivity. The UAM-V Process Analysis utility was used to identify physical and chemical mechanisms which contributed to O3 formation and destruction and indicate the key importance of entrainment from elevated layers generated by the highly complex meteorological conditions in determining near surface O3 concentrations.  相似文献   
208.
Thirteen pairs of blue-footed boobies (Sula nebouxii) were observed on their colony. Pairs courted frequently and, on average, copulated 24 times during the 30 days before laying, with 38% of those copulations occurring in the last 5 days (presumed fertile period). Males and females increased attendance at the nest site as laying approached. Seven females performed an average seven extra-pair copulations, with 1–2 paired male neighbors, but these were less concentrated in the presumed fertile period than within-pair copulations, and the last two copulations of all 7 females were with their social mates. Rates of female extra-pair copulations were six times lower when their social mate was present, and during the presumed fertile period, no female performed an extra-pair copulation in the presence of her mate. Males did not respond to infidelity of social mates with aggression, prompt copulation, retaliatory copulation, or increase in copulation. Seven of 13 males performed an average of five extra-pair copulations, with 1–3 paired female neighbors, before their own mates began egg-laying. The males' extra-pair copulations represented only 4% of their total copulations during their own mates' presumed fertile periods. Females, the larger sex, apparently control sexual access and copulate with extra males to achieve extra-pair fertilization. Males pursue a mixed strategy: they copulate with extra females, mostly outside their own mate's presumed fertile period, and they copulate increasingly with their social mate as laying approaches, probably assuring some paternity by mate guarding, involving attendance and courtship. Behavior of males and females is also consistent with other hypotheses for extensive joint nest site attendance: pairbonding, copulation access, and territory acquisition. Received: 14 November 1997 / Accepted after revision: 16 May 1998  相似文献   
209.
中国生物多样性保护适应气候变化的对策   总被引:1,自引:0,他引:1  
基于气候变化对生物多样性影响的总结分析,初步提出了我国生物多样性保护适应气候变化的对策。气候变化对生物物候、分布、迁移活动、群落结构、栖息地质量、生态系统和景观多样性都产生了一定影响,未来将产生更深刻的影响。我国生物多样性保护适应气候变化需要从物种有效保护、自然保护区规划与管理、灾害防御等方面进行。  相似文献   
210.
A decision support tool aiming to facilitate discussion and transparency in land-use planning processes has been developed. It includes process steps initiating with an analysis of the current situation, identification of relevant actions and sustainability analysis steps. The sustainability was subdivided into human health and environment, resources, and social and economic impacts. The main difference between this risk analysis tool and others is the allowance of comparisons of present risks and consequences of measures early in the process. It also includes assessments from short- and long-term perspectives, such as taking into account climate change. It combines classic risk analysis with life-cycle assessment procedure. It has been developed and tested in co-operation with municipalities. The tests show that the tool is applicable and can be relevant in the planning process. It offers an iterative discussion framework that is systematic, condensed and yet a simplistic way of describing consequences. The criticism is that it is regarded as time demanding, but this can be managed by preparatory work.  相似文献   
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