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991.
992.
基于多枢纽城际应急管理网络资源调度鲁棒优化 总被引:1,自引:2,他引:1
为了降低由于应急突发事件随机性带来的应急资源需求不确定性,在对基于Multi-HUB(多枢纽)城际应急管理网络机制研究的基础上,分析基于Multi-HUB城际应急管理网络信息传递和资源调度方式,建立以时间最小为目标的资源优化调度模型并鲁棒性地选择一级HUB点,通过Matlab7.0对优化调度模型及一级HUB点鲁棒性选择进行了数值仿真。研究表明:对Multi-HUB城际应急管理网络中的一级HUB点进行鲁棒性选择,能很好地对"都市圈"内应急资源进行优化调度,降低需求不确定性所带来的"都市圈"内资源无法有效整合的风险,从而有效地提高城市应急资源利用效率。 相似文献
993.
本文介绍了大型吹砂吹尘综合试验系统的设备构成和系统设计应考虑的关键技术。阐述了主要功能和技术指标,论述了砂尘浓度、试验段风速、试验段温度和相对湿度等主要试验参数的调节技术,并给出了应用结果。能够为大型吹砂环境试验设备的设计和试验应用提供参考借鉴。 相似文献
994.
Lisa M. Kurian Laura K. Lautz Myron J. Mitchell 《Journal of the American Water Resources Association》2013,49(2):264-283
Abstract: More than 85% of NO3? losses from watersheds in the northeastern United States are exported during winter months (October 1 to May 30). Interannual variability in NO3? loads to individual streams is closely related to interannual climatic variations, particularly during the winter. The objective of our study was to understand how climatic and hydrogeological factors influence NO3? dynamics in small watersheds during the winter. Physical parameters including snow depth, soil temperature, stream discharge, and water table elevation were monitored during the 2007‐2008 winter in two small catchments in the Adirondack Mountains, New York State. Snowpack persisted from mid‐December to mid‐April, insulating soils such that only two isolated instances of soil frost were observed during the study period. NO3? export during a mid‐winter rain‐on‐snowmelt event comprised between 8 and 16% of the total stream NO3? load for the four‐month winter study period. This can be compared with the NO3? exported during the final spring melt, which comprised between 38 and 45% of the total four‐month winter NO3? load. Our findings indicate that minor melt events were detectable with changes in soil temperature, streamflow, groundwater level, and snow depth. But, based on loading, these events were relatively minor contributors to winter NO3? loss. A warmer climate and fluctuating snowpack may result in more major mid‐winter melt events and greater NO3? export to surface waters. 相似文献
995.
On the Role of Spatial,Temporal, and Climatic Forces on Stream Sediment Loading from Rural and Urban Ecosystems 下载免费PDF全文
Audrey L. Squires Jan Boll Erin S. Brooks 《Journal of the American Water Resources Association》2017,53(5):1195-1211
In this study, we characterize the greatest sediment loading events by their sediment delivery behavior; dominant climate, watershed, and antecedent conditions; and their seasonal distribution for rural and urban land uses. The study area is Paradise Creek Watershed, a mixed land use watershed in northern Idaho dominated by saturation excess processes in the upstream rural area and infiltration excess in the downstream urban area. We analyzed 12 years of continuous streamflow, precipitation, and watershed data at two monitoring stations. We identified 137 sediment loading events in the upstream rural section of the watershed and 191 events in the downstream urban section. During the majority of these events conditions were transport limited and the sediment flush occurred early in the event, generally in the first 20% of elapsed event time. Statistical analysis including two dozen explanatory variables showed peak discharge, event duration, and antecedent baseflow explained most of the variation in event sediment load at both stations and for the watershed as a whole (R2 = 0.73‐0.78). In the rural area, saturated soils combined with spring snowmelt in March led to the greatest loading events. The urban area load contribution peaked in January, which could be a re‐suspension of streambed sediments from the previous water year. Throughout the study period, one event contributed, on average, 33% of the annual sediment load but only accounted for 2% of the time in a year. 相似文献
996.
997.
脉冲清灰系统是袋式除尘器和电袋除尘器的关键技术之一。通过理论估算的方法确定系统关键参数的初值,并依靠在脉冲喷吹试验平台试验的方法来获得最优的设计参数。 相似文献
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999.
Source apportionment studies of TSP(atmospheric particulate matter with aerodynamic diameters≤100μm)and PM10(atmospheric particulate matter with aerodynamic diameters≤10μm)have revealed that soil dust is all important source of these particulates in China In this study, the contamination of soil dust was assessed through the use of a geoaccumulation index(Igeo). The mass concentration profiles ofl7 elements(Na, Mg, AI, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br, Ba, andPb)were establishedforurban soil dusts. Geochemical cOmpositions of soils from 15 cities were used to represent background urban soil compositions. The results of this Studv indicated that a number of cities are severely polluted by particulates containing Ca, Cr, Ni, and Cu in both size fractions(TSP and PM10). Contamination with Zn, Pb, Co, and Br was moderate to severe(Igeo>2). The AI and Fe concentrations were not high enough for them to be considered contaminants. 相似文献
1000.