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181.
The authors analysed a proportional valve with electrical position feedback for its failure behaviour. Severalfailures were introduced into the feedback loop, especially into the 2 solenoids and the inductive positiontransducer. The behaviour of the valve for square and ramp reference signals was recorded and systematicallyanalysed. It was shown that failures could be detected by monitoring the residual signal from the equipmentunder control or the residual signal from the sensor. It was possible to achieve the safe position within twice thenormal response time of the valve by switching off the current of both solenoids. The application of these resultsfor a new generation of safe proportional valves is discussed. The use of the results of these investigationsobviates the need for redundancy of the electrical position monitoring arrangement in a safe proportionalvalve.  相似文献   
182.
One of the dimensions treated as part of a company’s safety culture or climate is workers’ attitudes towards risk and safety. In the present study these personal aspects are defined as workers’ safety culture, which is understood as a way of acting focused on life and taking care of one’s health. A questionnaire on safety culture was filled out by 200 employees of a metallurgical enterprise. Factor analysis was used to determine empirical scales of the questionnaire, whereas variance analysis was used to test hypotheses. The results confirmed the hypotheses that people who experienced accidents, dangerous situations, and—to a lesser extent—health problems had a lower level of safety culture. Nevertheless not all of the scales determined during factor analysis turned out to be significant as far as all kinds of those undesirable situations are concerned. Proposals for future studies are formulated in the conclusion.  相似文献   
183.
The management of municipal waste is one of the most emotive local environmental issues in the UK at present and represents a key sustainability “battleground” as local authorities seek to reduce waste arisings and encourage the reuse and recycling of materials among households. Within the literature on household waste management, a broad range of disciplinary perspectives and practical recommendations exist and it is the aim of this paper to step back and take stock of the role of households and communities in resource consumption and waste generation patterns across the UK within recent decades. By exploring the household in this context, trends in consumption and waste generation are outlined in addition to key influencing factors such as lifestyles and well-being, demographics and environment. Finally, key lessons learnt, challenges faced going forward and approaches for developing more sustainable practices at the household, community and national levels are discussed.  相似文献   
184.
Abstract

This paper addresses the relevance of the demand side for the achievement of sustainable transport in urban areas. The underlying thesis is that a better understanding of user habits, perceptions and attitudes with its specific dynamics is essential for a successful design of targeted transport policies. In line with this, the paper at hand is based on research that aims at improving the knowledge of urban-transport-related habits and attitudes of young adults. The results of three interview meetings that were held in Karlsruhe, Budapest, and Copenhagen with participants aged between 20 and 30 are presented. Background of the interviews is a range of studies that indicate that young people in urban areas seem to be less interested in cars than the generation before. And indeed, the interview meetings reveal that participants had a rather pragmatic attitude towards transport modes. They wished a transport system that is flexible, convenient and cheap. Despite many differences, most participants showed rather positive attitudes towards policies supporting alternatives to car-based transport. However, it will be crucial for policy shaping to what extent the observed behaviour patterns and attitudes will persist over time.  相似文献   
185.
Understanding how private landholders make deforestation decisions is of paramount importance for conservation. Behavioural frameworks from the social sciences have a lot to offer researchers and practitioners, yet these insights remain underutilised in describing what drives landholders’ deforestation intentions under important political, social, and management contexts. Using survey data of private landholders in Queensland, Australia, we compare the ability of two popular behavioural models to predict future deforestation intentions, and propose a more integrated behavioural model of deforestation intentions. We found that the integrated model outperformed other models, revealing the importance of threat perceptions, attitudes, and social norms for predicting landholders’ deforestation intentions. Social capital, policy uncertainty, and years of experience are important contextual moderators of these psychological factors. We conclude with recommendations for promoting behaviour change in this deforestation hotspot and highlight how others can adopt similar approaches to illuminate more proximate drivers of environmental behaviours in other contexts.Supplementary informationThe online version of this article (10.1007/s13280-020-01491-w) contains supplementary material, which is available to authorized users.  相似文献   
186.
Microemulsion polymerization is widely used as a cleaner alternative way to prepare intrinsically conductive polymers. We studied isothermal phase diagrams for microemulsions of the electropolymerizable heterocyclic aromatic oil 3,4-ethylenedioxythiophene (EDOT), aqueous LiClO4 solution and alkyl polyethoxylate. Our specific goal was to assess the effect of LiClO4 salt on the phase behaviour. The phase behaviour was characterized by stepwise titration and microscopic analyses. Here we found that the increase of the concentration of LiClO4 salt shifts the microemulsion region to lower surfactant content.  相似文献   
187.
The term “sustainability” has been a part of local, national, and international environmental discussions for well over a decade. First legitimized by the United Nations in 1987 with the release of the Brundtland Commission and Our Common Future (WCED, 1987), the term “sustainability” is now often used in more mainstream contexts. However, given our continued global ecological decline (Millennium Ecosystem Assessment, 2005), the question remains: do decision makers within organizations really have a clear idea of what sustainability is? Further, are they able to communicate that vision in such a way as it can be operationalized within their organizations?Organizations are faced with a high degree of uncertainty when attempting to move towards sustainability. The immense amount of literature and information available about the concept is daunting, especially for harried managers of small businesses who must respond to many competing needs and interests. Although many concepts, frameworks, and tools are available for business executives to use, there have been relatively less attempts to develop a rigorous, applied definition of sustainability that can be clearly understood, implemented, and measured within and across organizations. Given the abundance of concepts, frameworks, and tools, with the corresponding dearth of overarching frameworks, one may wonder what are executives learning from all this literature, and how it is being diffused into strategy, planning, and operations? This study aims to gain insight into executives’ thinking around definitions and the implementation of sustainability practices in Nova Scotia. The findings of this study indicate that there are three key relationships of significance in this area including: type of definition and ease of articulation; type of definition and type of experience; and type of definition, type of experience, and integration of strategic and operational planning.  相似文献   
188.
189.
Construction and demolition wastes are suitable for use in road construction. However, leaching characterization of recycled materials is required to determine their pollutant potential and the consequence of their application in different scenarios. The motivation of this paper is derived from the increasing use of different leaching test methods. In Europe, the confusion resulting from the wide variety of tests used to evaluate environmental properties of construction materials implies that an evaluation of the current practices and the attempt to consolidate the approaches are required.Two equilibrium-based leaching tests (the Dutch test and the European standard) were conducted to assess the environmental impact of four recycled aggregates. Three natural limestone aggregates were used as controls. Both tests measure the potential release of hazardous elements under extreme conditions using different leaching parameters (L/S ratio, pH value and contact time). The results proved that pH is the most relevant factor on the assessment of the differences between leaching methods due to its strong control on the pollutant release.To classify the materials according to their environmental effects, the concentration limit values of the metals imposed by Council Decision 2003/33/EC were used as a reference. The comparison allowed the classification of the recycled aggregates as inert wastes, with the exception of the MR-2 aggregate, which was classified as non-hazardous material.  相似文献   
190.
Three studies were designed to extend a combination of vested interest theory (VI) and the extended parallel process model of fear appeals (EPPM) to provide formative research for creating more effective disaster preparedness social action campaigns. The aim was to develop an effective VI scale for assessing individual awareness and ‘vestedness’ relevant to disaster preparedness. Typical preparedness behaviours are discussed with emphasis on earthquakes and tornados in particular. Brief overviews of VI and the EPPM are offered, and findings are presented from three studies (one dealing with earthquakes, and two with tornados) conducted to determine the factor structure of the key VI components involved, and to develop and test subscales derived from the two theories. The paper finishes with a discussion of future research needs and suggestions on how the new subscales may be applied in the design and execution of more effective disaster preparedness campaigns.  相似文献   
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