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41.
42.
起重机用减速器承载能力和选用方法探讨 总被引:1,自引:0,他引:1
本文对起重机减速器的承载能力和选用方法的分析表明,工作级别M1-M8中,其相邻级别按1.12的比例折算功率稍大但比较接近于理论值,把M5的额定功率确定为连续工作状况的2倍则与理论值相差过大,因此,硬齿面齿轮减速器没有必要再去划分工作级别,通用的选用2方法同样适用于志重机减速器的选用。 相似文献
43.
自然通风潜力的多标准评估方法 总被引:1,自引:0,他引:1
自然通风技术是建筑可持续发展的一个重要发展方向,而自然通风潜力是评价自然通风的重要指标。自然通风潜力应综合考虑热压、风压、空气质量、环境噪声对自然通风应用效果的影响。本文采用Qualiflex矩阵对我国八大城市的自然通风潜力进行了多标准评估分析。其中引入自然压差帕时数来表征热压、风压潜力影响值,建立了自然通风潜力与压差帕时数、空气质量、环境噪声之间的函数模型,并通过计算分析,得到八大城市的自然通风潜力最优排列及综合比较结果。 相似文献
44.
Helen Clare Lingard Keith Townsend Lisa Bradley Kerry Brown 《Construction Management & Economics》2013,31(10):1101-1112
Project‐based construction workers in the Australian construction industry work long and irregular hours and experience higher levels of work‐to‐family conflict and burnout than office‐based workers, giving rise to an interest in alternative work schedules as a means of supporting work–life balance. Alternative work schedules were implemented in four case study construction projects in Australia. Interventions differed between projects, with two implementing a compressed work week, and the others introducing reduced hours schedules (one of which was optional). Data were collected from each case study project, using various combinations of focus groups, surveys, interviews and daily diary collection methods. The results were mixed. The compressed work week appears to have been favourably received where it was introduced. However, waged workers still expressed concerns about the impact on their weekly ‘take‐home’ pay. Attempts to reduce work hours by changing from a six‐ to a five‐day schedule (without extending the length of the working day between Monday and Friday) were less favourably received. Waged workers, in particular, did not favour reduced hours schedules. The results confirm the existence of two distinct labour markets operating in the Australian construction industry and markedly different responses to alternative work schedules, based upon whether workers are waged or salaried. The results clearly show that attempts to improve work–life balance must take the structural characteristics of the industry's labour markets into consideration in the design of interventions. The impact of alternative work schedules is likely to be moderated by institutional working time regimes within the construction industry. 相似文献
45.
推行"阳光规划",能进一步增强城乡规划工作的透明度,有效地监督城乡规划的实施,维护百姓的正当利益.当前规划公示过程中存在的诸多问题,是由于阳光规划制度与体制上存在不足,从机制建设上完善科学合理的阳光规划制度,旨在全面有力地推进我国城市规划决策的公开化、民主化、科学化进程. 相似文献
46.
本文结合福州市城市规划管理技术规定(暂行)以及规划局日照要求提出了如何在不同日照标准下的总平面布局及建筑户型的选择,提高了地块容积率,保证了人们享受日光的权利。 相似文献
47.
“阳光规划”的实践与探索 总被引:4,自引:0,他引:4
“阳光规划”是浙江省率先在全省城乡规划领域推行的一项新的规划公众参与制度。通过建章立制.注重配套基础设施建设、加强监督等措施,将规划公众参与机制落到实处,提出了赋予公众参与的法律地位、拓展公众参与规划的层次及探索新型的公众参与方式的设想。 相似文献
48.
Lockridge RS Kjellstrand CM 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(2):211-218
Nightly home hemodialysis (NHHD) has been reported to have a much better survival than the excessive mortality of thrice-weekly in-center dialysis, but the factors influencing survival of NHHD have not been investigated in detail. We studied the association of survival in a 12-year study of 87 NHHD patients from a single center evaluating demographic, sociologic, and anthropomorphic factors, diagnosis, comorbidity, vintage, and dialysis performance and efficiency. Secondly, we compared the survival of the 87 NHHD patients with that reported by the United States Renal Data System (USRDS) using standardized mortality rate (SMR). The average patient age was 52 ± 15 years, and 59% were males, 51% African Americans, and 25% had diabetes. The patients dialyzed 40 ± 6 hours weekly with a stdKt/V of 5.25 ± 0.84. Thirteen patients died. The cumulative survival was 79% at 5 years and 64% at 10 years. Using Cox proportional hazards univariate analysis, 7 of 26 factors studied were associated with mortality: less than high school education, hour of each dialysis, comorbidities, secondary renal disease, congestive heart failure, Leypoldt's eKt/V, and Daugirdas Kt/V. In backward stepwise Cox analysis, education and hour of dialysis were the only factors independently associated with survival. The standardized mortality rate was only 0.30 of that reported by the United States Renal Data System for patients on thrice-weekly hemodialysis adjusted for age, gender, race, and diagnosis. The influence of education was the most significantly associated with survival, and the duration of each dialysis treatment was important. The survival rate of NHHD patients appeared to be superior to intermittent hemodialysis. 相似文献
49.
Vingilis E McLeod AI Seeley J Mann RE Beirness D Compton CP 《Accident; analysis and prevention》2005,37(3):549-556
PURPOSE: On 1 May 1996, Ontario, Canada amended the Liquor Licence Act to extend the hours of alcohol sales and service in licensed establishments from 1 to 2 a.m. The purpose of this study was to evaluate the road safety impact of extended drinking hours in Ontario. METHOD: A quasi-experimental design using interrupted time series with a nonequivalent no-intervention control group was used to assess changes. The analyzed data sets are total and alcohol-related, monthly, traffic fatalities for Ontario, for the 11-12 p.m., 12-1 a.m., 1-2 a.m. and 2-3 a.m. time windows, for Sunday through Wednesday nights and for Thursday through Saturday nights, for 4 years pre- and 3 years post-policy change, compared to neighbouring regions of New York and Michigan. RESULTS: The blood alcohol concentration positive driver fatality trends reflected downward trends for Sunday-Wednesday 12-2 a.m. and Thursday-Saturday 1-2 a.m. for Ontario and downward trends for Thursday-Saturday 12-1 a.m. and 2-3 a.m. for New York and Michigan after the extended drinking hour policy change. Ontario total fatality data showed similar trends to the Ontario blood alcohol positive trends. CONCLUSIONS: The multiple datasets converge in suggesting little impact on BAC positive fatalities with extension of the closing hours. These observations are consistent with other studies of small changes in alcohol availability. 相似文献
50.