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141.
The question of tank failure is addressed for both cryogenic (LFG) and atmospheric (Crude Oil) designs. An analysis of the consequences of an assumed axisymmetric mode of failure of a liquid storage tank is presented in an effort to answer the question.  相似文献   
142.
Safety related problems encountered in the production and handling of materials using monomers in water based polymerization reactions are covered. It must be noted that the author's experience is specifically in acrylic monomers.  相似文献   
143.
While the magnitude of potential consequences might vary, most hazards encountered in pilot plant operations are the same as those experienced in full scale commercial facilities. For example, safeguarding hazardous chemicals storage and transfer, protecting reaction vessels against catastrophic failure or runaways, all require careful consideration regardless of scale. We, however, want to address some aspects of pilot plants which can introduce hazards unique or more common to their operation. To illustrate, we present some case histories from our own pilot plant experience in BASF's Chemical Engineering Department, and include a brief discussion of some corresponding safeguards to mitigate these situations.  相似文献   
144.
145.
Transient processes important to understanding technical change are modeled using a time-varying version of the Sequential Interindustry Model, SIM. A simple process of technical change is explored, where a new production technique replaces an old one for one of an industry's production processes. Using several measures internal and external to the industry the model can help in understanding the complex processes of technical change, point to difficulties in their analysis, and suggest guidance to further examinations. An earlier version of this paper was presented at the Eighth International Conference on Input-Output Techniques, Sapporo, Japan, July 1986.  相似文献   
146.
There has been a great deal of investment in development of design criteria and design and construction of heavily reinforced, blast-resistant control rooms. This remains the best option for protective construction against severe blast loading experienced close in to a vapor cloud or other explosion hazard. However, most structures encountered at chemical plants and contemplated for future construction are conventional steel frame, metal clad buildings. In this paper we look closely at the response of such buildings to explosion loads and their ability to undergo large deformations without structural failure. The types of structural elements evaluated include metal decking of various gauge and shape along with a variety of girt and purlin sections. Building frames or bents are also evaluated, although the date base for these is much more limited. The work is based on observations made during investigations of large explosion accidents along with analytical predictions and test measurements. To conclude, we offer specific design criteria and connection recommendations for enhancing the overall strength of a building through the use of conventional components in unconventional construction.  相似文献   
147.
Cycling-inclusive urban planning is attracting attention worldwide because of the environmental, health, economic, and transport benefits inherent to cycling from the individual and the societal perspectives. The Czech Republic is one of the emerging cycling countries that are trying to promote and support cycling, but cycling mode shares are low because of the poor quality of the scarce infrastructure and the psychological barrier of the perceived lack of safety when cycling in mixed traffic. This study takes a multimodal approach based on the Theory of Planned Behaviour and focuses on the factors underlying the willingness to share the road from the perspective of cyclists and drivers: positive attitudes toward cycling, positive attitudes toward cyclists’ behavior, social norms toward cycling and anxiety to share the road. A web-based questionnaire was tailor-designed and administered in the Czech Republic via social networks, web forums, and the Civinet network, and a hybrid bivariate-ordered model tested the behavioral framework. Results show that the willingness to share the road as a cyclist or as a driver relates positively to positive attitudes towards cycling and cyclists’ behavior, and negatively to the anxiety of sharing the road. Moreover, mediator effects are observed and a clear relation emerges between the experience on the road as both a cyclist and a driver on the willingness to share the road as a cyclist. Lastly, results show that the factors underlying road sharing intentions are related significantly to gender, travel habits, and perceived personal and infrastructure-related barriers to cycling.  相似文献   
148.
The purpose of this study was to develop an instrument to measure adult awareness of consumer product/service information sources, consumer protection laws and channels of recourse. The process included identification of prevalent consumer problems, development of test items based on the identified problems, and assessments of the content validity and the reliability of the instrument. The process of construct validity was initiated by developing and testing hypotheses concerning the relationships between scores on the instrument and selected socio-economic characteristics of consumers. Low consumer awareness scores were predominant, supporting the need for consumer education for adults.  相似文献   
149.
Before embarking on the development of rural areas or regions it seems necessary to answer the following key questions: what goals of the parties involved can be realized, and where, when and how? To tackle these questions we have developed a ‘roadmap’, as part of an overall sustainable development procedure for physical planning and spatial management in rural areas. The roadmap is a tool for the process manager and the people involved. It helps to find the way in the exploration of the potential social, economic and ecological benefits of developing the area or region. The purpose of using the roadmap is to alleviate doubts about the advantages of cooperating in pursuit of sustainable development. A back-casting approach is applied to create appealing visions of the future and visualize mutual opportunities worth implementing. In this article we first describe the need for this new roadmap. We then describe its use, step by step and in some detail. An example of the exploration process is described and the strengths and weaknesses of the roadmap are discussed.  相似文献   
150.
The Core-Walras Equivalence is examined in a finite or infinite economy in which the competitive gap is bounded by the size of the atoms in the economy. The economy is represented by a Boolean algebra of coalitions, and coalitions rather than individual agents are taken as a primitive concept. Coalition arbitrage plays the central role in our analysis.  相似文献   
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