Use of Nash's IUH and DEMs to identify the parameters of an unequal‐reservoir cascade IUH model

Under the assumption that hydrograph generation was affected by n linear reservoirs with the same value of storage coefficient k, Nash proposed the formulation of the Instantaneous Unit Hydrograph (IUH), which has been widely used in rainfall–runoff simulation and flood forecasting. However, the assumption of the parameter k having the same value in all reservoirs is obviously unphysical as it results in the estimated value of n not being integral. In this study, for parameter n integral, the different k value for each reservoir was derived using the Laplace transform and developing a general rule for the equation of the IUH of any order. The relationship between parameter k and the slope of the river channel estimated using digital elevation model (DEM) data is established, the parameter estimation procedures are given. As in most unit hydrograph studies, only isolated storm events are considered here. Seventeen flood events in three catchments were selected for the case studies. Application results show that the proposed method is slightly better than Nash's IUH with higher model efficiency and smaller absolute relative errors. This work provides a new methodology for the formulation of the IUH. Copyright © 2008 John Wiley & Sons, Ltd.     

Quantitative Analysis of Micro-structural Changes in a Bituminous Coal After Exposure to Supercritical CO2 and Water

Natural Resources Research - High-volatile bituminous coal samples were reacted in deionized water with supercritical CO2 (ScCO2–water) under simulated in situ pressure and temperature...     

论渔业法之未取得或违反船网工具指标造船违法行为的法律责任

船舶是渔业生产、水上运输的重要工具,我国对渔业船舶借助船网工具控制指标管理模式达到对渔船数量和功率数控制的“双控”管理,但实践中碍于很多因素还存在未取得或违反船网工具指标造船的现象,这一行为对水域交通安全、渔业生产安全、渔业资源保护3个方面都存在安全隐患。文章主要梳理现行法律法规对这一行为的规定并简要分析其法律责任,建议在处罚幅度中增加处罚下限。     

包头西6.4级地震临震前宏观异常的研究

通过对包头６．４级地震临震前动物、地下水等宏观异常时、空、强分布特征的研究,提出了利用动物、地下水震前宏观异常加强短临追综研究,进行短临预报的思路和方法。     

平庄盆地六家立井地区找铀目标层岩石学特征及其找矿意义

六家立井地区位于平庄盆地北缘,白垩系下统阜新组上段是该区砂岩型铀矿床目标层位,具有较好找铀前景。为深入了解该区砂体的岩石学特征,通过野外钻探工作、岩心编录、样品采集及岩矿测试方法,详细研究了目标层碎屑岩类型、碎屑岩成分、结构构造等岩石学方面特征。结果表明目标层碎屑岩成分成熟度和结构成熟度均较低,具有搬运距离短、沉积速度快的特点,其物源较单一,初步判断物源来自盆地东北部和西北部隆起带酸性花岗岩,同时也为铀成矿提供了良好的铀源。     

含铀物质对有机质生烃的实验研究

采用密闭容器水热模拟实验方法,考察含铀物质对有机质热解生烃过程的影响。对热模拟实验产物分析发现,在暗色泥岩和煤岩样品中加入含铀物质后,气态烃和液态烃的生烃量都有比较明显的增加。其中煤岩的气态烃产量平均增加值为34%,而泥岩样品平均增加值也达到了30%以上。液态烃产率分析表明,含铀矿物也促进了泥岩和煤岩的液态烃产率。从泥岩氯仿沥青‘A’族组成分析表明,加入催化剂后泥岩的饱和烃和芳烃在高温阶段具有规律性的明显增大的趋势,反映出非烃和沥青质,甚至不溶有机质向相对稳定的饱和烃转化以及芳烃随演化程度增加的高聚合作用。综合以上分析,认为放射性铀对油气生成具有氧化催化作用。     

Pulsatory characteristics of wind velocity in sand flow over typical underlying surfaces

Pulsatory characteristics of wind velocity in sand flow over Gobi and mobile sand surface have been investigated experimentally in the wind tunnel. The primary goal of this paper is to reveal the relation- ship between pulsatory characteristics of instantaneous wind speed in sand flow and the motion state of sand grains. For a given underlying surface, pulsation of wind velocities in sand flow on different heights has a good correlation. As the space distance among different heights increases, fluctuation of instantaneous wind speed presents a decreasing trend and its amplitude is closely related to the mo- tion state of sand grains and their transport. Pulsatory intensity increases with the indicated wind speed, but its relative value does not depend on it, only agrees with height.     

岩溶含水介质渗透性空间结构分析的模型及其应用

岩溶含水介质渗透性的空间分布具有随机性与结构性的双重性质,本文探讨了运用区域化变量理论研究岩溶含水介质渗透性空间结构特征的数学模型及多数的物理意义,并阐述了具体的应用方法。为了综合表征岩溶含水介质渗透性的空间变异特点,给出了方向综合变异指标Ｄｖ。      

Earthquake magnitude estimation using the τc and Pd method for earthquake early warning systems

Earthquake early warning （EEW） systems are one of the most effective ways to reduce earthquake disaster. Earthquake magnitude estimation is one of the most important and also the most difficult parts of the entire EEW system. In this paper, based on 142 earthquake events and 253 seismic records that were recorded by the KiK-net in Japan, and aftershocks of the large Wenchuan earthquake in Sichuan, we obtained earthquake magnitude estimation relationships using the τe and Pa methods. The standard variances of magnitude calculation of these two formulas are ±0.65 and ±0.56, respectively. The Pd value can also be used to estimate the peak ground motion of velocity, then warning information can be released to the public rapidly, according to the estimation results. In order to insure the stability and reliability of magnitude estimation results, we propose a compatibility test according to the natures of these two parameters. The reliability of the early warning information is significantly improved though this test.