The lack of flood measurement data due to complex and changeable landform brings about many incon-veniences to hydro-project construction in southwest China. According to data of design flood peak discharge (Qp) and collecting area(F) at 66 hydrologic stations in 11 basins in the southwest region of China,the relationship be-tween Qpand F is researched by statistical analysis. Results show the Qp-F relationships in the Jialing River basin, Tuojiang River basin, Fujiang River basin, Minjiang River basin and Lancang River basin follow linear relation-ship;while in the Dadu River basin,Qingyi River basin and Yalong River basin,the Qp-F relationships match well with exponential relationship;and in the Jinsha River basin,Nujiang River basin and Yarlung Zangpo River basin the relationships conform well to power function. The research results offer reference for obtaining the Qp-F relation-ships in ungauged river basins.

The manage-flood, a new concept, is firstly proposed for reservoirs engineering management, and compared with the design-flood. The same and differences between the two kind floods have been analyzed in detail. Two standards for judging the rationality of the manage-flood has been proposed in this paper, one is about such condi-tions that are satisfied to some management demands, and the other is about flood control safety that is satisfied to the standards. This paper summarized two kinds of analysis methods about the manage-flood. One method is based on the maximum of seasonal flood, and the other based on the maximum of the annual flood. The two methods have respective advantages and disadvantages. The results of the former can′t conform completely to the flood control standards while the former has lower requirements for observed data. The results of the later can conform the flood control standards but the later has higher requirements for observed data and no application experiences.

从确定性与不确定性的角度,探讨了相似预测的基本理念并论述其应用于水文学的基础,以此提出了从选取特征矢量到构造预测量的完整算法.重点分析构造预测量的方法,通过分析未来出现的数值可能围绕均值左右摆动的特性,并促使应用者主动考虑预测值的不确定性,提出平均区间和序位区间的概念,为区间预测方法研究提供参考.将此理念及方法应用于宜昌站1890-2010年的年平均流量资料进行检验,结果表明:该方法对宜昌站年径流量的预测效果较好,能较好地描述径流在年尺度的变化,又能促使应用者发挥主观能动性,主动考虑预测值的不确定性.

论述以下几个关键问题:①涉水工程防洪安全设计零风险理念导致极限洪水新概念;②极限洪水的四大特性;③可能极限洪水的新见解;④极限洪水和万年一遇洪水既对立又统一,不能孤立地对待;⑤在敲定极限洪水采用值时合理性分析至关重要.

The nearest neighbor method ( NNM) based on hydrological similarity is a data?driven prediction method, the use of which allows for avoiding making certain assumptions about the dependence and probability distribution forms of objects of study. One of the key factors that affect the quality of the predicted results using this method is the selection of the measure of the similarity in eigenvectors. In order to give consideration to the information about“direc?tion” and “quantity” while measuring similarity, this paper tries to couple Cosine distance and Euclidean distance to the technical indicator for similarity after thoroughly analyzing their differences and similarities. The nearest neighbor method based on coupled similarity indictor was used for the annual runoff prediction of Yichang hydrological station and Tangnaihai hydrological station, and the annual runoff data for different hydrological characteristics were used for checking. The results show that the nearest neighbor method based on the coupled indicator can appropriately predict annual runoff. It is an effective, feasible method.