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911.
回顾 1.需求 在中国政府持续的宏观经济调控政策的影响下,10月份国内固定资产投资增长继续回落,但经济增长依然旺盛,特别是出口增长出乎意料地强劲.大多数地区工农渔业生产处于旺季,但受国庆长假的影响,估计10月份石油平均消费水平比上月略有下降,至93.97万吨/日,同比增长6.96%.从油品市场看,由于高温天气全面结束以及煤炭运输计划的缩减,汽油需求较9月份有所回落;农业、渔业及工程建设用柴油需求进入高峰季节,但个别地区柴油市场受到国庆长假和走私油的影响.估计10月份国内汽油需求为14.10万吨/日,比上月下降0.89%,同比增长8.42%;柴油需求为32.76万吨/日,比上月上升2.50%,同比增长6.29%;需求的柴汽比为2.27(见表1). 相似文献
912.
913.
The effects of consumer education and information treatments on choice of alternative products are described. Knowledge of upholstery serviceability and flammability before and after these treatments is measured as well as simulated purchase behavior of 448 Canadian consumers. Subjects show an increase in knowledge between pre- and posttests. The choice of fire resistant upholstery differs among consumer information treatments but not among education treatments. The policy implications of these findings are discussed. 相似文献
914.
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
915.
An Incident Investigation system based on a combination of Fault Tree Analysis logic and the Deming Principles of Systems and Quality was developed during a three-year period. The system was given an excellent test in the investigation of the explosion of a tank car filled with methacrylic acid. In this case, the Event Tree constructed during the investigation was easily converted into a Fault Tree. The Fault Tree so constructed was then used to evaluate the effectiveness of proposed corrective changes to the production, loading, and analytical systems before the changes were actually implemented. By making use of these tools to guide the addition of feedback loops (“And” Gates in fault Tree terminology), the intrinsic safety of the methacrylic acid production and shipping system was greatly enhanced at a relatively low cost. 相似文献
916.
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
917.
Sigal Kaplan Igor Mikolasek Hana Bruhova Foltynova Kira H. Janstrup 《International Journal of Sustainable Transportation》2019,13(5):350-362
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
918.
John E. McCarthy 《英国劳资关系杂志》2019,57(1):182-201
I find that school union representatives’ ‘boundary spanning’ communications throughout the school district predict the diffusion of knowledge between schools. Hence, my data reveal school union representatives as critical conduits for improvement‐related knowledge transfer and innovation. Yet, I also find that these external networks interact strongly with the level of workforce participation characterizing each school: The effects of external networks on internal knowledge diffusion are considerably stronger in more participative schools compared to less participative schools. This research contributes to industrial relations scholarship by demonstrating how union‐related institutions can foster unique social structures that directly strengthen innovation‐related capabilities, as well as how the efficacy of these networks depends on managerial norms at different areas of the organization. This study is also of timely practical relevance at a time when labour unions are increasingly painted as obstacles to, rather than potential facilitators of, improvement and innovation. 相似文献
919.
Past research has reported that learning processes in early stage R&D are either chaotic, or absent. We challenge this finding by elaborating Van de Ven et al.’s trial‐and‐error learning model and explore an alternative conceptualization. We explored the combinations of positive and negative outcomes and action course continuation and modification. We use data gathered in an R&D setting of a 4‐years pre‐competitive knowledge generation project in the Dutch paper and board industry. Whereas the Van de Ven and Polley (1992) approach applied on our data also would lead us to conclude that ‘no learning’ would happen, our decomposed model identified three distinct learning patterns: (1) a virtuous pattern of positive outcomes resulting in continuations of action courses; (2) a vacuous pattern of negative outcomes resulting in modifications of action courses; and (3) a verification pattern of positive outcomes resulting in modifications of action courses. We observed the virtuous and verification patterns during the first 2 years and virtuous and vacuous learning in the second 2 years. These results might be useful for R&D managers since they provide insight into how an early stage R&D project can develop and where managers might intervene and adjust action courses. 相似文献
920.
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