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91.
依据资本观、能力观等相关理论,构建了以情绪智力为中介变量的施工企业内社会资本与安全绩效关系的理论模型,并以156家施工企业为调查对象而获取的数据进行多元回归分析。研究结果表明:员工情绪智力在施工企业内社会资本的结构维度、关系维度与安全绩效之间起到完全中介作用,在认知维度与安全绩效之间起到部分中介作用。因此,施工企业应该重视企业内社会资本的积累,同时加强员工情绪智力的提升,提高安全绩效。  相似文献   
92.
人工神经网络模型在水质预警中的应用研究进展   总被引:1,自引:0,他引:1  
水质预警模型是大数据时代构建环境智能决策与管理体系的关键技术.近年来,水质自动化监测能力的提升以及测管协同对环境模型的强烈需求,激发了研究人员探索新的建模方法并努力提高模型预测性能.其中,人工神经网络(Artificial Neural Network, ANN)模型发展迅速.本文综述了3大类ANN模型的发展历史和模型结构特点,梳理了ANN模型在水质数据软测量、数据异常检测和时间序列预测等方面的研究进展,归纳了一般建模流程、技术建议和常用的模型性能指标,发现ANN模型的应用依赖于监测数据质量,存在模型可解释性差、模型运行硬件资源要求较高等不足,提出未来水质预警模型的研发思路和重点,需要加快推进水环境监测技术与预警模型的协同发展和业务化应用,通过多种应用场景检验实现技术迭代,形成大数据驱动的水质在线监测-智能预警-应急管理支撑体系,助力我国环境治理能力现代化.  相似文献   
93.
根据作者在仪器使用和维修过程中的一些经验,介绍TH880Ⅳ型智能烟尘平行采样仪在实际应用中遇到的问题,并提出相应的解决方法及建议。  相似文献   
94.
Evolving policies to regulate pollution from animal feeding operations   总被引:2,自引:0,他引:2  
Due to concentrations of animals at large facilities, animal feeding operations (AFOs) have emerged as a major potential source of water pollution. The federal government regulates concentrated animal feeding operations under its point-source pollution permitting regulations. A major determinant of whether an operation must apply for a permit is the number of animals at an individual lot or facility. This paper examines federal mandatory controls and voluntary guidelines that seek to reduce contaminant pollution from AFOs. Land treatment practices are delineated due to their importance in reducing the injurious by-products of agricultural production. An evaluation of proposed revisions to federal regulations on confined animal feeding operations suggests they diverge from their goal of controlling water pollution. Federal regulations focus on the size of operation and amount of manure governed by the permitting process to the exclusion of other criteria related to the impairment of water quality. Given the uncertainties about the amount of pollution from AFOs, lack of enforcement of existing regulations, localization of problems, and possible alternatives for addressing the pollution, more demanding federal regulations may not form an appropriate response.  相似文献   
95.
Recent policy developments in the area of livestock husbandry have suggested that, from the perspective of optimizing animal welfare, new animal husbandry systems should be developed that provide opportunities for livestock animals to be raised in environments where they are permitted to engage in “natural behavior.” It is not known whether consumers regard animal husbandry issues as important, and whether they differentiate between animal husbandry and other animal welfare issues. The responsibility for the development of such systems is allocated jointly between farmers, regulators, different actors in the food chain, and consumers. This research focuses on understanding consumer attitudes and preferences regarding the development and introduction of such systems, to ensure that they are acceptable to consumers as well as producers, regulators, and scientists. Consumer perceptions of animal welfare and animal husbandry practices were evaluated using quantitative consumer survey, which focused on two animal husbandry issues – farmed pigs and farmed fish. Following pilot work, 1000 representative Dutch consumers were sampled about their attitudes to either pig or fish husbandry. The results indicated that consumers think about animal welfare in terms of two broad categories related to their health and living environment, but do not think about welfare issues at a more detailed level. Greater concern was expressed about the welfare of pigs compared to fish. Consumer trust in labeling also emerged as an important issue, since consumers need to trust different food chain actors with responsibility for promoting animal welfare, and are reluctant to consider the details of animal husbandry systems. As a consequence, a transparent, enforceable, and traceable monitoring system for animal welfare friendly products is likely to be important for consumers.  相似文献   
96.
We synthesize findings from neuroscience, psychology, and behavioral biology to show that some key features of cognition in the neuron-based brains of vertebrates are also present in the insect-based swarm of honey bees. We present our ideas in the context of the cognitive task of nest-site selection by honey bee swarms. After reviewing the mechanisms of distributed evidence gathering and processing that are the basis of decision making in bee swarms, we point out numerous similarities in the functional organization of vertebrate brains and honey bee swarms. These include the existence of interconnected subunits, parallel processing of information, a spatially distributed memory, layered processing of information, lateral inhibition, and mechanisms of focusing attention on critical stimuli. We also review the performance of simulated swarms in standard psychological tests of decision making: tests of discrimination ability and assessments of distractor effects.  相似文献   
97.
西湖与青山水库底栖动物群落的研究   总被引:4,自引:0,他引:4  
通过对杭州市的两个主要水体西湖和青山水库的底栖动物群落包括种类组成、优势种群、生物量等的比较研究。西湖和青山水库底栖动物群落主要由寡毛类和摇蚊幼虫组成 ,存在适应低溶氧、耐有机污染的种群。从底栖动物群落生态学角度评价了西湖和青山水库水体的营养化程度。  相似文献   
98.
Animals’ contest performance is influenced by their recent contest experiences. This influence could either be exerted by individuals re-estimating their own fighting ability (self-assessment) or by their opponents responding to status-related cues (social-cue mechanism) or both. Individuals of Kryptolebias marmoratus, a hermaphroditic killifish, were given different contest experiences to examine how two opponents’ prior experiences combined to determine their contest interaction and to test both of these mechanisms as potential causes of the observed experience effect. Our data showed that losers’ decisions to retreat at different stages of a contest were influenced by their own but not by the winners’ contest experience—a result consistent with self-assessment but not with the social-cue mechanism. An association between the fish initiating and winning contests thus probably arose because both were correlated with an individual’s assessment of its fighting ability, but not because initiating contests made opponents more inclined to retreat.  相似文献   
99.
The study described in this paper developed a model of animal movement, which explicitly recognised each individual as the central unit of measure. The model was developed by learning from a real dataset that measured and calculated, for individual cows in a herd, their linear and angular positions and directional and angular speeds. Two learning algorithms were implemented: a Hidden Markov model (HMM) and a long-term prediction algorithm. It is shown that a HMM can be used to describe the animal's movement and state transition behaviour within several “stay” areas where cows remained for long periods. Model parameters were estimated for hidden behaviour states such as relocating, foraging and bedding. For cows’ movement between the “stay” areas a long-term prediction algorithm was implemented. By combining these two algorithms it was possible to develop a successful model, which achieved similar results to the animal behaviour data collected. This modelling methodology could easily be applied to interactions of other animal species.  相似文献   
100.
畜牧业的生产和发展推进了社会的发展,但同时也造成了生态环境的污染,给人类及其他生物的健康生存构成了很大威胁( 危害) ,况且这一问题已日趋突出。本文旨在介绍畜牧污染的危害及其特点,以期引起全社会的广泛关注,并提请有关方面给予高度重视  相似文献   
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