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考虑水库调蓄影响的设计洪水计算方法
Design Flood Estimation at Downstream Section by Considering the Impact of Upstream Reservoir Regulation
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章君, 郭生练,天元, 徐长江
Journal of Water Resources Research (JWRR) , 2012, DOI: 10.12677/JWRR.2012.14029
Abstract: 水库的调蓄作用,改变了其下游天然洪水的水文情势,直接影响下游断面的设计洪水。以清江流域梯级水库为例,通过基于Copula函数的条件期望和最可能地区组成,结合规范采用的同频率地区组成方法,拟定了五种水布垭水库和区间流域洪水组合方案,推求受水布垭水库调蓄影响的隔河岩断面设计洪水。计算结果表明:与天然情况相比,考虑水布垭水库调蓄的不同重现期隔河岩断面设计洪水均减小。削减最大的是条件期望组合方案,最小的是条件期望组合方案。规范采用的同频率方法有一定的代表性,但它既不是最可能发生的,也不是对隔河岩断面防洪最不利的情形。研究成果可以供清江梯级水库防洪调度与运行管理参考,同时为水库下游断面设计洪水计算提供了一条新思路。
The hydrological regime of the natural flood has been changed because of the reservoir storage and regulation, which directly impact on design flood in the downstream section. The Shuibuya-Geheyan cascade reservoirs in the Qingjiang basin were chosen as the case study. Five schemes based on the conditional expectation, most likely composition and same frequency methods were used to analyse flood regional combination of the Shuibuya reservoir and interval basins. The design floods of the Geheyan section were estimated by considering the impact of the Shuibuya reservoir regulation and compared with that of natural condition. The results show that design peak discharges of five schemes are reduced; the maximum and minimum values are estimated by the conditional expectation I and the conditional expectation II schemes respectively. The same frequency methods are neither the most likely to occur, nor the most unfavorable circumstances for flood control of Geheyan section. This study not only can provide references for the Qingjiang cascade reservoirs operation and management, but also provide a new way for design flood estimation at reservoir downstream section.
基于Copula函数的梯级水库设计洪水地区 组成研究
Regional Flood Composition of Cascade Reservoirs Based on Copula Function
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章君, 郭生练,天元, 徐长江
Journal of Water Resources Research (JWRR) , 2014, DOI: 10.12677/JWRR.2014.32018
Abstract: 目前工程设计中常用的同频率地区组成带有一定的人为性,统计理论基础不足。利用Copula函数推导了两种考虑空间相关性的梯级水库设计洪水地区组成,即条件期望组成和最可能组成。以清江流域为例,对三种地区组成进行比较研究,分析了上游水布垭-隔河岩梯级水库的调蓄对高坝洲断面设计洪水的影响。结果表明:同频率组成计算的设计结果系统偏小,可能会增加设计断面的防洪风险。基于Copula函数的两种组成充分考虑了各分区洪水的随机性和空间相关性,设计成果比较合理。受上游梯级水库调蓄的影响,高坝洲断面千年一遇设计洪水的削峰率为40%左右
The equivalent frequency regional composition method is widely used in practice. However, this method is based on artificial hypothesis and lacks the statistical basis. Two statistical composition methods, i.e. the conditional expectation method and the most likely method are proposed and derived based on Copula function. The Qingjiang cascade reservoirs are selected as the case study and the impact of Shuibuya-Geheyan cascade reservoirs regulation on the design flood of Gaobazhou dam site is analyzed. It is demonstrated that the results of equivalent frequency method are systematically smaller than those of the two proposed methods, which may lead to increasing the hydrological estimation risk. The proposed methods with strong statistical basis can capture the spatial correlation of flood events for each contributing watershed area, and the estimated design flood values are more reasonable than those
梯级水库设计洪水方法及研究进展
Review of Design Flood Estimation Methods for Cascade Reservoirs
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天元, 郭生练, 李妍清, 章君
Journal of Water Resources Research (JWRR) , 2012, DOI: 10.12677/JWRR.2012.12003
Abstract: 流域上游修建水库后将改变下游河道的洪水特性,直接影响下游断面的设计洪水,因此应该考虑上游水库的调洪影响及设计断面以上各部分洪水的地区组成。针对我国目前主要采用同频率组成法和典型年组成法来拟定设计洪水地区组成的现状,综述梯级水库设计洪水的研究进展,分析现有方法的优缺点,探讨推求梯级水库设计洪水的新途径,并提出进一步开展研究工作的建议。
The construction of upstream reservoirs will certainly change the flood characteristics and affect the design floods in the downstream river. As a result, the reservoir operation and regional composition of upstream and inter-basin inflows should be considered when estimating design flood in the downstream controlled sections. The equivalent frequency and typical year synthesis are the most frequently used regional composition analysis methods in China, the research advancement of design flood estimation methods for cascade reservoirs are summarized and reviewed. New approaches of design flood derivation for cascade reservoir are also discussed by assessing the advantage and disadvantage of these methods. The research directions of design flood for cascade reservoir are also suggested.
鄱阳湖与长江干流洪水遭遇规律及风险分析
Flood Coincidence Risk Analysis for the Middle Yangtze River and Poyang Lake
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天元, 郭生练, 章君, 刘国强, 曾思栋
Journal of Water Resources Research (JWRR) , 2014, DOI: 10.12677/JWRR.2014.36062
Abstract:
本文引入von Mises分布及其混合形式拟合年最大洪水发生时间与间隔时间,应用Copula函数分别构造汉口、湖口两站年最大洪水发生时间二维联合分布和年最大洪水发生时间(间隔时间)与洪水量级的三维联合分布,分析了研究两站年最大洪水在时间、量级及过程三个方面的遭遇风险。结果表明:鄱阳湖和长江年最大洪水在7月16日遭遇的可能性最大,约为0.058%,鄱阳湖和长江年最大7d洪水过程发生遭遇的概率为7.31%。研究可为鄱阳湖流域防洪规划制定和生态经济区建设提供科学依据。
The von Mises distribution was used to fit the series of annual maximum flood occurrence and in-terval dates. The Copula functions were used to establish the bivariate joint distribution of annual maximum flood occurrence dates and the multivariate joint distribution of interval dates and flood magnitude. The flood coincidence risk of annual maximum flood occurrence date, flood magnitude and flood process were analyzed based on the data series of Hankou and Hukou hydrological stations. The results show that the highest flood coincidence risk of annual maximum flood occurrence date and 7-day flood process between the middle Yangtze River and Poyang Lake may reach to 0.058% (on July 16th) and 7.31% respectively during the flood season. The research can provide scientific basis for Poyang Lake basin on flood prevention planning and ecological- economic zone construction.
水库对下游断面的防洪作用分析
Impact of Reservoir on Downstream Flood Prevention
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章君, 郭生练,天元, 熊立华
Journal of Water Resources Research (JWRR) , 2014, DOI: 10.12677/JWRR.2014.36067
Abstract:
流域上游建库蓄水改变了水库下游断面洪水的情势,必须定量地评价水库对下游断面防洪形势的影响。建立了水库对下游断面的防洪作用评价模型,以清江流域为例,分析水布垭水库对隔河岩断面的防洪作用。研究结果表明:水布垭水库和区间均发生千年一遇洪水,隔河岩断面洪峰流量在无水布垭水库时为22,880 m3/s,有水布垭水库时为21,570 m3/s,洪水重现期从1000年减小为550年。水布垭水库和区间均发生二百年一遇洪水,经水布垭水库调蓄后,相当于天然情况下水布垭水库和区间均发生百年一遇洪水。水布垭水库的修建提高了下游隔河岩断面的防洪能力。
The hydrological regime of the natural flow at the downstream site has been changed after the reservoir was built. The quantitative evaluation of reservoir’s flood prevention function for the downstream site is very important and an assessment method is established. The Shuibuya reservoir in the Qingjiang basin was chosen as the case study. The flood prevention function at the Geheyan site with or without reservoir was compared and analyzed. If 1000-year flood both occurred at Shuibuya reservoir and interval basin, the peak discharges at Geheyan site were equal to 22,880 m3/s and 21,570 m3/s without and with Shuibuya reservoir respectively, and the return period was reduced to 550 years. If 200-year flood both occurred at Shuibuya reservoir and interval basin, it was equivalent to 100-year natural flood condition after reservoir storage regulation. This study indicates that the flood protection standard of the Geheyan site is greatly improved when the Shuibuya reservoir has been built.
中国东北地区4个活火山群的火山灾害
,隋维国,天元
地质论评 , 1999,
Abstract: 东北地区有4个活火山群,它们是长白山火山群、五大连池火山群、龙岗火山群和镜泊湖火山群。这些活火山群中的活火山有潜在的喷发危险,一旦再次爆发,由火山喷发空中降落堆积物、火山泥流、火山碎屑流、火山碎屑崩塌和熔岩流等造成的灾害和环境污染将是巨大的。当务之急是重塑火山喷发历史和模式,编制火山灾害预测图。东北地区火山灾害类型如此之多,影响范围如此之广,进行专项火山灾害调查研究是必须的。
长白山天池地区全新世以来火山活动及其特征
,隋维国,天元,王锡魁
第四纪研究 , 2004,
Abstract: 长白山火山全新世规模最大的喷发活动发生在公元1199-1200年,即800年前的大爆发,被确定为普林尼或布里尼(Plinian)式喷发。这次大爆发形成体积巨大的、分布广泛的以空中降落堆积物为主的火山喷发碎屑堆积物,在长白山火山周围,远至日本都留下了地质记录。文章辨认并划分了这次大爆发火山碎屑物的成因类型:火山喷发空中降落堆积物(airfalltephra)、火山碎屑流(pyroclasticflow)状堆积物和火山泥流(lahar)堆积物,并且点、面结合,近、远和国内、国外兼顾,分析了这些火山碎屑物的主要特征、分布和相互关系,进而确定这些火山碎屑物分别属于两次普林尼式爆发。第1次(早期)普林尼式爆发称赤峰期,火山喷发模式为:普林尼式喷发柱(赤峰空落浮岩层)-火山碎屑流(长白山火山碎屑流层),随即主要由火山碎屑流诱发火山泥流(二道白河火山泥流层);第2次(晚期)普林尼式爆发称园池期,喷发模式为:普林尼式喷发柱(园池空落浮岩火山灰层)-火山碎屑流(冰场火山碎屑流层)。在层序上将气象站期碱流岩置于800年前大爆发火山碎屑物之下是正确的,其时代为晚更新世-全新世早期。
涟邵矿区的槽波特征
天元
煤田地质与勘探 , 1990,
Abstract:
茶多酚鞣化柞蚕丝素粉的抑菌作用研究
天元
食品科学 , 2001,
Abstract: ?采用不同的方法对柞蚕丝素粉进行鞣化处理,通过抑菌实验发现,以茶多酚为鞣化剂的柞蚕丝素粉对口腔中主要致病、致菌有较强的抑制作用。最低抑菌浓度对微小消化链球菌3×103cfμ/ml,mic为0.075mg/ml,对致主要菌变异链球菌3×106cfμ/ml,mic为0.15mg/ml,提示该种丝素粉可用于口腔防。
紫苏酱贮存期化学热力学动力学分析
天元
食品科学 , 2002,
Abstract: ?紫苏子皮的防止油脂及食品氧化功能,为其广泛应用开辟了良好前景。本研究在实验基础上,用理论分析、计算方法阐明了其防腐作用的化学动力学规律,并指出了其应用的条件与动力学性质的关系。
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