• 全国中文核心期刊
  • 中国科技核心期刊
  • 美国工程索引(EI)收录期刊

1996 Vol. 7, No. 1

Display Method:
Computation and Study of the Tidal Chart in Chinese Offshore Waters
Han Xiaohong, Zhao Mingcai
1996, 7(1): 1-7.
Abstract:
The practial formulae with more perfection for the solution of tidal differential equations are presented in this paper. Then the tidal charts in a 30'×30' grid,with the boundary points as the known condition and the tide gauge in the sea as the control and check,are computed in the Chinese offshore waters. With the comparisons of in-situ data,it is concluded that the accuracy of amplitude (H) of the partial tide is ±15cm and the accuracy of lag angle (g) is ±20º,meeting completely the requirements of tidal corrections for the hydrographic survey in the sea. Finally,tidal charts and non-tidal points location are given,some propagation features of tidal wave in the Chinese offshire waters are also investigated and analysed. Meanwhile,some useful conclusions are obtained.
Numerical Simulation for Rainfall Infiltration with the Effect of Air Pressure
Tang Haixing, Su Yishen
1996, 7(1): 8-13.
Abstract:
The relationship between saturated hydraulic conductivity Ks and air pressure within rainfall infiltration experiment is investigated by a numerical simulation based on a one-dimensional infiltration model. The numerical analysis indicats that the computation method may be improved by decrement of Ks with saturation at the soil surface in consideration of air pressure formed in rainfall infiltration. Finally,the computation results in simulation of infiltration experiments show that the improved method is more accurate than normal.
Soil Moisture Monitoring at Field Scale
Yang Shixiu, Lei Zhidong, Wu Wanru, Duan Xingjie
1996, 7(1): 14-19.
Abstract:
Soil moisture monitoring at field scale is discussed in this paper. The characteristics of space and time-dynamic variance of soil moisture are analyzed on the base of in situ data,and accordingly,the rational sampling number of soil moisture monitoring can be determined. This study is aimed at improving the level of water-saving irrigation and field water use mamagement.
Senstive Index of Jensen’s Water Production Function Model of Wheat
Guo Qunshan, Lei Zhidong, Yang Shixiu
1996, 7(1): 20-25.
Abstract:
This paper calculates the actual and potential evaportranspiration of wheat based on the field water balance. furthermore,the sensitive index of Jensen's water production function model is analyzed. the result shows that the sensitive index is related to the growing stage duration of the crop and the ratio of each stage to the whole growing period. The accumulated sensitive index of each grow stage after green can be expressed as a function of time,but it is not related to the stage devision. Sensitive index of each stage can be easily calculated from the stage deviion. Sensitive index of each stage can be easily calculated from the function. The result also shows that the relation between crop water consumption and crop yield can be expressed by the jensen's model quite well.
Impact of Climate Change on Water Resources of Jing-Jin-Tang Region
Wang Jiansheng, Zhang Shifa, Huang Guobiao, Li Jiangqiang, Mao Fenglian
1996, 7(1): 26-36.
Abstract:
The effect of global climate change on water resources of Jing-Jin-Tang region in North China was studied using basin hydrological model and the comprehensive evaluation model for the water resources utilization of the region,diagnostic analysis of historic data was made and the GCMs output of climate change scenarios in the future was adopted. The study includes the impact of climate change on water resources quantity and its temporal and spatial variation and on water supply,water demand and sectoral water deficit in the region. The possible economic loss due to climate change impact was estimated.
Diagnostic Analysis of Historic Temperature and Precipitation in Beijing and Tian jin
Mao Fenglian
1996, 7(1): 37-41.
Abstract:
In this paper the trends of temperature and precipitation in North China and Northeast China and their relationshop are analysed using observed data in the past 100 years in Beijing,Tianjin,Shenyang and Haerbin stations. The result indicats that in the past 100 years annual mean temperature and monthly mean temperature in January in winter have a increase trend. And the magnitade of increase is greater in Northeast China than that of in creast in North China,the magnitade of the monthly mean temperature in Jan in winter is greater than that of the annual mean temperature. The monthly mean temperature in July in summer is a decrease trend in some regions. There is a inverse correlation between monthly mean temperature and precipitation,especially for May,June,July.
Effect of Rainfall on Hydraulic Resistance of Shallow Flow
Chen Guoxiang, Yao Wenyi
1996, 7(1): 42-46.
Abstract:
The hydraulic resistance of shallow water flow under the influence of rainfall has been investigated through the flume experiment with artificial rainfall. The effect of rainfall on the flow characteristics of shallow water has been analysed,the concepture of "False-laminar flow" has been suggested,and the formula of Darcy-weisbach resistance coefficient has been eastablished. The results of the study can be used in overland flow routing and soil erosion simulation.
Study on Sediment Yield Model of Basin
Tang Liqun
1996, 7(1): 47-53.
Abstract:
According to the dynamic balance condition of the soil particle on the sloping land,the critical shear stress of the fine silt on the sloping land is deduced. Based on the surplus transport capacity of the overland flow,a calculation formula of the soil erosion of the overland flow is obtained. With the calculation formula of the rainfall splash in the reference four,a mathematical model with clear conception and definite process and complete structure of sediment yield from watershed is developed. Sediment yield depends on the comparison relation of the transport capacity of flow and supply sediment. If transport capacity of flow less than supply sediment,the seiment yield is equal to the transport capacity of flow. Otherwise,the soil will be eroded by the overland flow,and the sediment yield is addtion of the supply sediment and runoff erosion. Therefor, the sediment yield from sloping land and watershed can be calculated. The model is verified with measured data of Chabagou catchment and the results are satisfactory.
Influence of Turbulence on Sediment Coagulation
Zhang Xingnong
1996, 7(1): 54-59.
Abstract:
In this paper the influence of turbulence on sediment coagulation is studied. The author discusses some theories of flocculation dynamics presented in many researches about wastewater treatment.and thinks that these theories fit to research of sediment coagulation. Based on the test of fine sand and compared with othors,the result shows that there are two periods in fines flocculation in turbulent flow in which the influence of trubulence on the flocculation is different.
A New Interactive Multiobjective Optimization Method and Its Application in a Water Resourse System
Wang Jianqun, Ye Bingru
1996, 7(1): 60-65.
Abstract:
A new interactive decision-making method to solve multiobjective optimization problems is presented. Some. theory about the method is given. The method can solve general multiobjective optimization problems,and can provide the decision maker with helpful trad-off information. The interactive in the method is practical,clear,and is more efficient to find the preferred solution. The method has used to solve optimized planning of a water resources system.
Probabilistic Planning Model of Water Pollution
Wang Deguan, YU Bo
1996, 7(1): 66-72.
Abstract:
This paper presents a stochastic waste water quality management model. This model finds the economically optimized treatment efficiency for each discharge source along a river while maintains the risks of water quality in the river below prescribed bounds..It takes into account over all the amount of effluent waste,diffusion,mixing processes of the waste in water,and especially,the stochastic property of the river flow,and gives the optimal beneficial result both environmently and economically. This model was applied to Tuojiang basin in Sichuan Province.
Rainfall Characteristic in the East Region of the Yellow River of Gansu Province
Peng Suqing, Yang Xingguo Lanzhou, Ke Xiaoxin, Zhang Xudong
1996, 7(1): 73-78.
Abstract:
Applying the automatical recording rainfall data of recently 15 year on 19 meteorology stations in the east region of the Yellow River of Gansu Province,the paper analyzes the scattering characteristic and occring number of rainfall under different rainfall-duration and-intensity between June and September. It is also made preliminary analysis about the comprehensive effect of rainfall-duration and-intensity on the rainfall.
Design and Application of the Flood Control Expert System to Fenhe River
Weng Wenbin, Luo Quang, Wang Xixi
1996, 7(1): 79-84.
Abstract:
The flood control decision support system for the midstream of Fenhe River (FCDSSMFR) is a artificial intelligence interaction network between user and computer,which is based on the theories of management science,operations research,control theory and social science,solves problems in terms of computer simulation and information techniques and has assisting functions to the flood control decision makers. FCDSSMFR consists of the following eight sub-systems:Graphical information sub-system,historical storm flood simulation sub-system, storm water forecasting sub-system,real time flood forecasting and regulating sub-system,artificial storm water simulation sub-system,artificial intelligence sub-system,database management sub-system and sensitive help. The flood control expert system for the midstream of Fenhe (FESOF) is the artificial intelligence (AI) analysis part of FCDSSMFR,which is the first practical model of expert system for flood control field in China. This paper discusses the main ideas of the designing of FESOF's system softwares and building of flood control expert knowledge bases, and describes FESOF's execution and expansion.
Introduction to Preferential Flow in Unsaturated Soil
Yaping Liu, Chuan Chen
1996, 7(1): 85-89.
Abstract:
Preferential flow is applied to describe heterogeneous flow phenomena through porous media. Under certain conditions,water and chemical movement in unsaturated soil is not just a simple one dimensional movement,instead often a heterogeneous flow situation,due to soil structures or wetting front instability. Preferential flow consists of macropore flow,funnel' flow,and finger flow. This paper reviews and summarizes studies on three types of preferential flow phenomena in theory,experiment and modeling.
ENCYCLOPEDIA OF LIFE SUPPORT SYSTEMS WATER,ENERGY, ENVIRONMENT, FOOD & AGRICULTURE
1996, 7(1): 90-91.
Abstract:
There is much present need for a knowledge source that presents an authoritative,comprehensive and integrated approaches to the science,technology and management of four essential natural resources necessary for life support:water,energy,environment and food & agriculture. Not only are these natural resources, together with air and land,necessary for life support on our planet;they must be orchestrated and enhanced through human engineering efforts to ensure that the resulting resources are truly sustainable and that they can be utilized for life quality enhancement. The Encyclopedia of Life Support Systems (EOLSS) is a source document for this knowledge,as well as document that contains encompassing discussions on the interactions and interplay in human activities,and associated infrastructure needs,that results in sustainable life support systems. As a source book for students,researchers and professional practitioners in efforts related to integrated approaches to sustainable development through systems management of natural and human engineered resources,the EOLSS will satisfy five critical needs.