河网

Under the inspiration of one-dim river-network computational pattern, was put forward the basic computing element concept of two-dim river-network.

受一维河网计算模式的启发，提出了河网二维基本计算单元的概念。

Based on the Saint-venant equations describing the channel flow movement, the nonlinear algebraic equations derived by the use of Preissmann weighted implicit four-point scheme are solved with the Netwon-Raphson method. A combined Gauss main-element elimination method with compress-storage technique is proposed. The relaxation iterative method for solving branch river networks is extended, which can turn the problem of any complex river networks into the problem of a series of single rivers. The coupling of hydraulic model with water quality model is built up. The combined model was applied to a large complicated river networks with numerical hydraulic structure which influenced by strong tide, storm and heave rain. Visualization of computational results is realized by means of MapInfo, which displays the computational results in fast, convenient and accurate way.

水力模型以描述河道洪水波运动的Saint-Venant方程组为基础，用Newton-Raphson方法直接求解按Preissmann加权四点格式进行离散所得的非线性代数方程组，提出了压缩存贮形式的Gauss列主元消去法并对数值解的收敛性进行了讨论；将支流流量的松弛迭代方法从树状河系推广到了环状河网，使任意复杂河网水力计算的问题都可化为一系列的单一河道的水力计算问题；建立了水力模型与水质模型的联接，初步应用于既有洪水、暴雨、强潮等综合影响，又存在多种水工建筑物及水力调度问题的大型复杂河网中的非恒定流水力、水质计算问题；利用MapInfo对计算结果的可视化进行了研究，有利于决策者快速、方便、准确地作出决策。

Considering the difference of runoff characteristics on different underlying surface in the area of plain tidal river network, four kinds of surface is divided,namely, waters paddy field-, dry land and central urbanized area,and suitable method is adopted separately in each surface to simulate runoff process. Xinanjiang Model usually applicable for mountain areas is introduced to river network area, furthermore, the paper researches runoff calculation of central urbanized area, the underlying surface is divided into pervious and imperviousness areas.In perviousness areas, Hoton Infiltration formula and corresponding spatial infiltration rate curve are used to establish the relationship between infiltration rate and soil moisture in order to decide the infiltration. According to practical situation.

根据平原河网区城市下垫面产汇流方式的不同，分成水面、水田、旱地、城镇四类，分别采用相对应的产流汇流计算方法，将适用于山丘区的新安江模型引入到平原河网区城市，同时对于城镇这类下垫面，从下渗角度考虑，划分成透水和不透水两种类型，根据霍顿下渗公式和下渗率空间分布曲线，建立下渗率和土壤含水量的关系，进而研制出城镇透水面的产流计算方法，城镇汇流根据实际情况可结合城市管道排水计算。

On the basis of scaleless transform of DEM data, this paper introduces a method of extracting stream network after the generalization, and the fractal transformation of square root model, which is the same with the quantity-fixed generalization model of the stream networks.

本文在DEM数据无级变换的基础上，从DEM中提取出综合前后的河网，并引入分形扩展的方根模型，得到适用于河网的定量综合模型，从而评估出变换后DEM的比例尺。

There existed significant relationship between stream structure and its function.

河网水系的结构与功能参数之间具有显著的相关水平，说明河网地区水系形态结构与功能密切相关。

It shows through the calculation of topographic shaping of typical regions and channel shaping of the river system of the middle Yellow River and preliminary analysis on interrelationship with gravity erosion that it is feasible to reflect the integrated factor of topography and geomorphy...

对黄河中游典型区域地形分形和河网沟道分形的计算及其与重力侵蚀相互关系的初步分析表明：通过分形来反映流域地形地貌综合因素是可行的；地形分形与重力侵蚀的关系较为紧密，可以用于重力侵蚀的宏观预测；河网分形与重力侵蚀的关系较弱。

In this paper divided the river network into two types: treelike network and annular network,and use time sequence observations on few observation points as the inversion of information, verified use of genetic algorithm inverse of the entire river networks roughness is feasible.

本文将河网分为环状和树状两种不同复杂的情况，把河网中部分观测点的时序列数据作为反演资料，验证了利用遗传算法反演整个河网中所有河段的糙率是可行的。

In this Paper analysis several different complexity of the river network, found that the more complex the river network, laid on the location of the observation points higher demand,and theannular network high sensitivity than the treelike network in the Observation points layout.

论文中分析了几个不同复杂情况的河网，发现对于越复杂的河网，对观测点的布设位置要求越高，环状河网的对监测点空间布置的敏感性比树状河网高。

And it's also pointed out that the factions such as configuration of complex networks, charactristics of flood, impounding of lakes or reservoirs, structuralized method in compiling programme etc.

第一章较为系统地介绍了河网数值模拟的发展状况，分析了河网模拟的两种方法，即水文学方法和水动力学方法的特点、演进以及优缺点。

The main works of this paper are as follows.First, according to the three-step method, 1-D unsteady flow model in river network is introduced. A new topological structure is presented to describe and store the topology information and data in river network ,which realises the connection between GIS and the numerical program of hydraulic calculating and turns the program into a universal one .A new formula of internal boundary conditions with double-recursion algorithm is deduced, and the relationship of recursive coefficient between imaginary channel length and non-imaginary channel length is presented ,which makes sure that the model can comprise the numerical simulation of the internal boundaries such as side pipe outflow ,barrage, slice gate and drainage pump station.

主要工作如下：(1)根据三级解法建立了一维河网非恒定流模型，并提出了一种新的数据结构来描述和储存河网拓扑信息，方便了GIS平台和数值计算程序的衔接，实现了三级解法程序的通用性；从河段方程组出发，根据虚设河段法推导出了内边界条件的双追赶法公式，指明了虚设河段的追赶系数和非虚设河段追赶系数的关系，从而使模型可以模拟集中旁侧入流、堰、闸、水泵等内边界对行洪过程的影响。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。