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991.
隧道火灾的防治一直是火灾科学研究的热点和难点.通过对公路隧道灭火技术的比较,指出细水雾灭火技术是适用于公路隧道消防保护的灭火技术.并在此基础上介绍了西欧一种新型的隧道型细水雾灭火系统,该系统采用模块化设计,每个保护区模块长18-20m,额定工作压力为1MPa,设计可靠、安装方便、维护成本低.在挪威Runehamar隧道开展了全尺寸实验,结果表明系统可成功控制和熄灭高达100MW的火灾.在全尺寸隧道火灾实验的基础上,进行了公路隧道内隧道型细水雾灭火系统的典型设计,为公路隧道细水雾灭火系统的应用及发展提供参考. 相似文献
992.
从教学资源、实训基地、实训项目、学生管理、评价体系五个方面对影响艺术设计专业实践教学规范管理因素进行分析,总结出艺术设计专业实践教学独特性与规律性并存的特点,在此基础上进一步阐明了艺术设计专业实践教学在教学资源管理、实训基地管理、实训项目管理、学生管理等方面的具体作法,并且对艺术设计专业实践教学规范化管理的实效性进行了深入探讨。 相似文献
993.
William D. Shuster Dennis Lye Armah De La Cruz Lee K. Rhea Katharine O'Connell Amanda Kelty 《Journal of the American Water Resources Association》2013,49(4):753-765
The collection, storage, and reuse of rainwater collected in rain barrels from urban rooftop areas assists municipalities in achieving stormwater management objectives and in some areas also serves as an adjunct resource for domestic water supplies. In this study, rainwater reuse and levels of select microbial indicators were monitored for six residential rain barrels located in the Shepherd Creek watershed of Cincinnati, Ohio. Water from rain barrels typically had poor microbial quality and was used for watering indoor and outdoor plants. Rain barrel water chemistry was slightly acidic, exhibited wide ranges in conductivity, turbidity, and total organic carbon (TOC) concentrations and gave no evidence of the presence of cyanobacterial microcystin toxins. Selected microbial water‐quality indicators indicated that counts of total coliform and enterococci were consistently above U.S. Environmental Protection Agency standards for secondary recreational contact water‐quality standards. Residential rain barrels can provide water appropriate for low‐contact reuses (such as plant watering), although there may be transient periods of high levels of indicator bacteria in the collected water. 相似文献
994.
Roger A. Nichols Gary L. Ketcheson 《Journal of the American Water Resources Association》2013,49(6):1367-1384
A federal, state, and private partnership leveraged resources and employed a long‐term, systematic approach to improve aquatic habitat degraded by decades of intensive forest management in Finney Creek, a tributary to the Skagit River of Northwest Washington State. After more than a decade of work to reduce sediment sources and the risk of landslides within the watershed, log jam installation commenced in 1999 and progressed downstream through 2010. Log jam design was adapted as experience was gained. A total of 181 log jams, including 60 floating log ballasted jams, were constructed along 12 km of channel. The goal was to alter hydraulic processes that affect aquatic habitat formation along 39 km of stream with emphasis on 18.5 km of lower Finney Creek. Aquatic habitat surveys over a five‐year period show an increase in the area of large pools and an accompanying increase in residual and maximum pool depth in the lower river reach. Channel cross sections show a generally deeper channel at the log jams, better channel definition in the gravel deposits at the head of the log jams, and improved riffle and thalweg development below the log jams. Stream temperature in the upper river decreased by 1.0°F in the first three years, and 1.1°F in the lowest treated reach over nine years. There is a trend of less stream heating over the restoration time period. Photo points show that riparian vegetation is recolonizing gravel bars. 相似文献
995.
Jafar Mahmoudi 《International Journal of Green Energy》2013,10(3):219-237
With the trend towards increasing the speed of processors in smaller sized of computers, there has been considerable interest in heat sink technologies with higher levels of performance and further miniaturization. This work addresses the fundamental heat transfer augmentation question of how to design a copper-based heat sink, when the overall dimensions of the bottom plate or fan are specified. A three-dimensional finite-volume model has been developed and applied to investigate flow and conjugate heat transfer in the copper-based heat sink. The model was produced with the commercial program FLUENT, which allows this nonlinear, highly turbulent problem to be simulated using the k-ε turbulence model. The theoretical model developed is validated by comparing the model predictions with available experimental data. The thermal performance and temperature distribution for the heat sink were analyzed and a procedure for optimizing the geometrical design parameters based on less space occupation and more efficient heat transfer coefficient is presented. Several design examples with different types of cooling methods and manufacturing processes have been analyzed. The reliability and effectiveness in heat spreading of those has been compared. It has been shown that the copper-based heat sink with louvered fins (case No.3) has an optimum design configuration. 相似文献
996.
997.
一家酒店发展前景与这家酒店现状息息相关,酒店发展需在现实基础上扬长避短,也就需要对现状因素进行整合,使之形成推动酒店发展的合力.于是首先对国林大酒店现状进行即时调查,并进行SWOT分析,在此基础上进行了酒店MI设计. 相似文献
998.
小流域地段景观生态设计研究——以大别山巴河上游地段为例 总被引:1,自引:0,他引:1
陈剑中 《长江流域资源与环境》1996,(1)
在实地调查研究的基础上,分析了巴河上游流域地段的景观结构功能与演替及流域治理存在的问题,切中流域生态环境变化的要害——水土流失问题。在区内景观带自然分异的基础上,进行了流域景观生态设计。 相似文献
999.
通过对比分析,阐述了FP型盘管空调器在盘管排数、管径、肋片型式等结构设计对热工性能的影响,以及合理设计水流速度。 相似文献
1000.