汶川震区清平乡文家沟泥石流灾害特征分析

2010年8月13日凌晨在四川省绵竹市清平乡暴发了16条泥石流,其中1条特大型(文家沟泥石流),1条大型(走马岭沟泥石流),9条中型,5条小型。清平乡场镇暴发的文家沟泥石流规模最大,泥石流冲出固体物质总量达310×104 m3,文家沟泥石流将清平乡老场镇的大部分区段淤埋。由于这场泥石流灾害发生在汶川地震高烈度区,是地震与降雨共同作用的结果,研究其形成原因,对于进一步认识强震区泥石流发育特征具有重要的意义。根据现场调查,从物源条件、地形条件、降雨条件分析了泥石流形成原因,并分析了泥石流成灾特征及成灾过程机制,以及泥石流运动特征等。     

R410A与R22在家用空调中的应用比较(2)

本文部分（2）利用Bin参数分析法对R410A与R22空调的全年运行耗电进行计算,采用寿命期气候性能（LCCP）指标对R410A与R22的温室效应总体影响进行考查,同时对R410A与R22空调的生产成本进行比较。结果表明R410A空调由于运行效率高,在使用过程中可以显著节约耗电和运行费用,而且随着原材料价格的上涨和R410A压缩机生产能力的扩大,R410A与R22空调具有相近的生产成本;同时,通过减小温室间接效应以及空调的制冷剂充灌量或泄露量,与R22相比,R410A反而还会有利于降低对气候变暖的影响。     

金属风暴武器阻拦射击面与分布密度关系

为提高金属风暴武器系统射击效能,根据舰载金属风暴武器系统的特点,建立了金属风暴武器系统饱和阻拦射击面和毁伤效能计算的数学模型并进行了实例仿真计算,研究了弹丸总数有限情况下的弹丸分布密度、阻拦射击面与毁伤效能之间的关系.实例仿真结果表明,在弹丸总数有限的情况下,目标命中平均弹丸数与必须毁伤命中数相等时,对应的阻拦射击面和弹丸散布密度能使毁伤概率最大.     

平潭综合实验区10kV电网架设方式选择

合理选择10 k V电网架设方式,对确保平潭综合实验区可靠性供电具有重要的意义。本文借助全寿命周期成本分析方法,综合考虑了10 k V电网工程建设投资和运维费用,选择年费用最小且可靠供电的10 k V电网架设方式。     

Assessing the mitigation effect of deep tunnels on urban flooding: a case study in Guangzhou,China

ABSTRACT

There are growing demands of deep tunnels to mitigate the severe urban flooding by providing a large storage capacity for excess storm runoff. This study aims to assess the flooding mitigation effect of a deep tunnel system proposed in the old downtown of Guangzhou, China, and to quantify the flooding volume difference by two storm hyetographs, the Chicago curve and the Improved Huff curve. Results show that the flooding volume is significantly reduced by a minimum of 19% and a maximum of 42% under design storms of 10- and 0.5-year return periods, respectively, when the deep tunnel system is constructed. There is a distinct spatial pattern for the mitigation effect. The best mitigation is in the west and the immediate north of the main tunnel, whereas the east does not show significant mitigation. Moreover, the actual flooding risk is likely underestimated when the Chicago curve is employed to design the storms.     

Statistical evaluation on storm sewer design criteria under climate change in Seoul,South Korea

This study conducted statistical analysis under both stationary and non-stationary climate using rainfall data measured in Seoul, South Korea. The 50 year annual maximum rainfall data were analysed with generalised extreme value distribution and Gumbel distribution. Possible rainfall changes were predicted with nonstationary forms of the two distributions, considering time variable location parameters. The current storm sewer design criteria were assessed by reflecting climate change implications and expected lifetime performance. Expected return periods were reduced to 4.67, 8.66, 19.16 and 23.53 years for the current 10 min - 5, 10, 30 and 50 years. The newly suggested design criteria of 5, 10, 30 and 50 yr return period storm events were 5.3, 12, 48 and 107 years for the 10 min duration for a 50 year lifetime expectancy.     

变压精馏分离甲苯-乙醇体系的经济最优化设计

甲苯-乙醇体系的共沸组成与相对挥发度对压力比较敏感,可用变压精馏分离该体系。利用Aspen化工流程模拟软件,以年度总费用最小为目标函数,以NRTL为热力学计算模型,采用序贯迭代法确定普通、部分热集成和完全热集成的变压精馏最优工艺参数。结果表明完全热集成更具有优势。     

柴河水库"05.8"暴雨洪水及调度

本文对柴河水库“05.8”暴雨洪水及其调度方式的选择进行了分析。分析表明,“05.8”洪水防洪预报调度方式,依据的信息量多,即可提高防洪安全,又能增加可利用洪水资源。     

逻辑斯谛模型在预测油气田可采储量中的应用

逻辑斯谛模型是一个属于增长类型的模型,经过简单的推导得到了开发时间、原始储量、可采储量的采出程度,以及采出程度与开发时间之间的关系。矿场实例运用表明：该模型计算简单、预测精度较高,可作为油田制定中、长期开发规划的依据。