Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of Korea Water Resources Association
Journal Basic Information
Journal DOI :
Korea Water Resources Association
Editor in Chief :
Volume & Issues
Volume 31, Issue 6 - Dec 1998
Volume 31, Issue 5 - Oct 1998
Volume 31, Issue 4 - Aug 1998
Volume 31, Issue 3 - Jun 1998
Volume 31, Issue 2 - Apr 1998
Volume 31, Issue 1 - Feb 1998
Volume 21, Issue 3 - 00 1998
Selecting the target year
A Study on Velocity-Log Conductivity, Velocity-Head Cross Covariances in Aquifers with Nonstationary Conductivity Fields
Seong, Gwan-Je ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 363~373
In this study, random flow field in a nonstationary porous formation is characterized through cross covariances of the velocity with the log conductivity and the head. The hydraulic head and the velocity in saturated aquifers are found through stochastic analysis of a steady, two-dimensional flow field without recharge. Expression for these cross covariances are obtained in quasi-analytic forms all in terms of the parameters which characterize the nonstationary conductivity field and the average head gradient. The cross covariances with a Gaussian correlation function for the log conductivity are presented for two particular cases where the trend is either parallel or perpendicular to the mean head gradient and for separation distances along and across the mean flow direction. The results may be of particular importance in transport predictions and conditioning on field measurements when the log conductivity field is suspected to be nonstationary and also serve as a benchmark for testing nonstationary numerical codes. Keywords : cross covariance, nonstationary conductivity field, saturated aquifer, stochastic analysis.
A Study on the Effects of the Type of Rainfall Distribution upon the Variation of the Critical Storm Duration : Sanbon Watershed
Yun, Yeo-Jin ; Jeong, Sun-U ; Jeon, Byeong-Ho ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 375~384
In determining design runoff for the design of drainage systems, the concept of critical storm duration is applied. However, rainfall distribution is usually determined without well-defined standards. In this paper, through the application of ILLUDAS model to Sanbon basin, which is a small urbanized watershed, effects of various rainfall distributing types upon the determination of critical storm duration are throughly analyzed. As a result, it is revealed that peak discharge rates as well as critical storm duration are greatly influenced by the applied of rainfall distributions such as uniform, triangular, trapezoid, huff, central type using IDF curve. Keywords : critical storm duration, rainfall distribution, urban runoff, design storm, ILLUDAS.
A Practical Research for Mode Efficient Utilization of Estuary Reserviors in the South-Western Part of Korea
Kim, Hyeon-Yeong ; Seo, Yeong-Je ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 385~396
The south-western part of Korea is situated in an unbalance of water supply and demand relating to the Keum, Mankyung, Dongjin and Youngsan River and their estuary reservoirs. For example, the Keum River estuary reservoir is discharging the larger amount of yearly runoff into the sea due to the small storage capacity, while Saemankeum estuary reservoir which is under construction, has the smaller runoff comparing with its strorage capacity. And the downstream area of the Youngsan River, such as Youngkwang, Youngam are deficient in water due to larger demand and smaller supply. In order to solve the above unbalanced water supply and demand and also to improve the water use effciency, the Hierarchical Operation Model for Multi-reservoir System(HOMMS) has been developed and applied to analyze the multi-reservoir operation assuming that the above reservoirs were linked each other. The result of this study shows that
of annual additional water requirement for agricultural and rural water demands are required in this region at 2011 of target year, and these demands can be resolved by diverting and reusing
of the released water from the estuary reservoirs into the sea.
Hydraulic Investigation of Pyokkolche Reservoir
Lee, Jang-U ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 397~406
The Pyokkolche Reservoir was constructed as a major public project of the ancient agricultural society, 1600 years ago. From a hydraulic point of view, it is considered to have been carried out with a distinguished technology. It should be in particular noticed that for a consecutive banking the main stream was diverted and drained to the Yonpo stream and the dam with same sea levels on its top along the whole length was built in a nearly straight line in spite of the different sea levels between both ends on the bottom. These suggest that the carrying out artifice and surveying technigue of those days were considerably excellent. However, the insufficient plan and design at the time of the construction, the temporary management and the repeated repair works in the later ages caused the Pyokkolche to lose its function. The Changsaenggeo and Kyungjanggeo gate sites being the facilities for sluices composed of a simple span and a vertical lift hand-operated sing a pully. The advantage of the geographical characteristics at both ends of the main dam was scientifically taken to these sites which also functioned as a spillway against a flood. The gate site of Suyogeo must have been located in an entrance to Suwolri, the northern end of the Pyokkolche and Yutonggeo is presumed to have been located on the right of Sangsori, the southern end of the Pyokklche. Keywords : Pyokkolche Reservoir, construction technology, gate site location.
Incorporating Climate Change Scenarios into Water Resources Management
Kim, Yeong-O ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 407~413
This study reviewed the recent studies for the climate change impact on water resource systems and applied one of the techniques to a real reservoir system - the Skagit hydropower system in U.S.A. The technique assumed that the climate change results in ±5% change in monthly average and/or standard deviation of the observed inflows for the Skagit system. For each case of the altered average and standard deviation, an optimal operating policy was derived using s SDP(Stochastic Dynamic Programming) model and compared with the operating policy for the non-climate change case. The results showed that the oparating policy of the Skagit system is more sensitive to the change in the streamflow average than that in the streamflow standard deviation. The derived operating policies were also simulated using the synthetic streamflow scenarios and their average annual gains were compared as a performance index. To choose the best operating policy among the derived policies, a Bayesian decision strategy was also presented with an example. Keywords : climate change, reservoir operating policy, stochastic dynamic programming, Bayesian decision theory.
Numerical Model for Flood Inundation Analysis in a River(I) : GIS Application
Lee, Hong-Rae ; Han, Geon-Yeon ; Kim, Sang-Ho ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 415~427
FIAS (Flood Inundation Analysis System) using Arc/Info is developed and applied to the South Han River basin. The DWOPER model is revised and expanded to handle simultaneous multiple overtopping and/or breaking and to estimate the inundation depth and extents. The model is applied to an actual levee overtopping case, which occurred on August 23~27, 1995 in the South Han River. Stage hydrographs inside and outside of the levee are compared, then inundated discharges from overbank spilling are computed. The Graphic User Interface is developed with AML(Arc/Info Macro Language). Two-and three-dimensional inundation maps by Arc/Info are presented. The computed inundation extends agree with observations in terms of inundation depth and flooded area. Keywords : River, Floodwave, Flood Inundation, Geographic Information System.
Numerical Model for Flood Inundation Analysis in a River(II) : Uncertainty Analysis
Lee, Hong-Rae ; Han, Geon-Yeon ; Kim, Sang-Ho ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 429~437
The numerical model named "DWOPER-LEV" for the uncertainty analysis of flood inundation is developed. DWOPER model is expanded to compute overtopping risks of levee and to predict the range of the possible flood extent. Monte-Carlo simulation is applied to examine the uncertainties in cross section geometry and Manning's roughness coefficient. The model is applied to an actual levee break of the South Han River. The risks of overtopping are computed and the possible range of inundated area and inundated depth are estimated.
Applications of Graph Theory for the Pipe Network Analysis
Park, Jae-Hong ; Han, Geon-Yeon ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 439~448
There are many methods to calculate steady-state flowrate in a large water distribution system. Linear method which analyzes continuity equations and energy equations simultaneously is most widely used. Though it is theoretically simple, when it is applied to a practical water distribution system, it produces a very sparse coefficient matrix and most of its diagonal elements are to be zero. This sparsity characteristic of coefficient matrix makes it difficult to analyze pipe flow using the linear method. In this study, a graph theory is introduced to water distribution system analysis in order to prevent from producing ill-conditioned coefficient matrix and the technique is developed to produce positive-definite matrix. To test applicability of developed method, this method is applied to 22 pipes and 142 pipes system located nearby Taegu city. The results obtained from these applications show that the method can calculate flowrate effectively without failure in converage. Thus it is expected that the method can analyze steady state flowrate and pressure in pipe network systems efficiently. Keywords : pipe flow analysis, graph theory, linear method.
Calculation of Run-up Height on a Conical island with Variable Transverse Lengths of Incident Waves
Jo, Yong-Sik ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 449~457
Using a numerical model solving the shallow-water equations, unusual huge run-up heights observed in the lees of both Babi and Okushiri islands were investigated in detail. The effects of incident tsunami widths were particularly examined by adjusting the transverse length of the wave-maker in laboratory and numerical experiments. The calculated run-up heights were compared with the laboratory experimental data. It has been found that the run-up heights in the lee of a conical island are strongly dependent on the ratio of a transverse length of incident tsuanmis to a base diameter of the island. Keywords : shallow-water equations, tsunami, run-up height, conical island.
Effective Method for Analysis of Heterogeneous Porous Media
Park, Chang-Geun ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 459~467
The existing methods to analyze the heterogeneous porous media based on the similar media concept are the microscopic Miller similitude(MiS), the macroscopic Miller similitude(MaS) and the Warrick similitude(WS). The inter-relationship is found such that MiS ⊂ MaS ⊂ (⊂:subset). The proposed method is based ont eh assumption that the scale variables
=w and the moisture content is dimensionless by introducing the effective degree of saturation instead of the degree of saturation into WS. The method, without the loss of generality in view of the inspectional analysis, can explain the heterogeneity of the media by using the scale variable
only. The media of
=1 (average of
) means the equivalent media corresponding to the heterogeneous media, while the standard deviation of
may explain the degree of the heterogeneity of the media under consideration. The hydraulic conductivity of the media with
>1 is greater than that of the equivalent media, and the effective moisture content of the media with
>1 is also greater. Based on these properties of the scale variable
, the ideal vertical one-dimensional heterogeneous porous media is generated by using the technique of random number generation.
Point Frequency Analysis for Determining the Design Flood at Indogyo Site
Yun, Yong-Nam ; Won, Seok-Yeon ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 469~481
A point frequency analysis is carried out for the Indogyo site at the Han river using 68 annual maximun flood data for the period of 1918-1992. Computed frequency discharges using the three parameter log-normal, type-I extreme value, type-III extreme value, and Pearson type-III computed as 35,500 m3/sec and 39,000 m3/sec, respectively, 33,500 m3/sec and 37,500 m3/sec of corresponding return periods are computed when the flood control effect of the dams are taken into account. The resulting flood discharge of 37,500 m3/sec is similar to the current design flood of 37,000 m3/sec in downstream reach of Han river, so, it could be desirable to keep the the current design flood, considering the increasing tendency of the flood due to the climate change. Keywords : frequency analysis, flood discharge, Han river.
A Study of Water Transfer between Han River and Nakdong River Basins
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 483~490
The possibility of water transfer from Han river basin to Nakdong river basin by connecting them is studied as an alternative to solve water shortage problem in Nakdong river basin. After estimating the amount of water shortage from Nakdong river basin, the amount of water surplus from Han river basin is estimated by using simulation and optimization techniques. HEC-5 is used to study small to medium size reservoirs as a simulation technique and dynamic programming is used to study multi-purpose reserviors as an optimization technique. Also, the cost of the interbasin water transfer from Han river basin to Nakdong river basin is also compared with that of constructing new reserviors in Nakdong river basin. If new reservoirs are constructed in Nakdong river basin as planned, water supply can satisfy various water demands until 2021 without the interbasin water transfer. In economic point of view, constructing new reserviors has an advantage over the interbasin water transfer. Keywords : interbasin water transfer, simulation, optimization, dynamic programming, HEC-5, water right conflict.
Two-Dimensional Flow Analysis of Approach Channel for the Design of Spillway Guidewall
Lee, Gil-Seong ; Kim, Nam-Il ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 491~501
Numerical simulations were performed to analyse the flow pattern of the approach channel and to design the spillway guidewall for stable flow conditions. RMA-2, two dimensional finite element model which can easily represent complicated geometry was used, and model parameters were estimated from the observation data of hydraulic model test. Numerical experiments were made separately for the approach region and for the upstream region, and upstream boundary position of the hydraulic model beyond which the boundary effects are negligible was determined from the numerical results. For the stable flow condition in approach channel, alternative designs for guidewall were developed, and flow analysis for alternative designs was done through the numerical simulation. From the analysis of alternative design, we can see that the flow pattern in the approach channel is stable and the lateral stage difference disappears mostly before the spillway crest. Keywords : Spillway, Guidewall, Flow analysis, RMA-2
Daily Runoff Simulation at River Network by the WWASS(Watershed Water balance And Streamflow Simulation) Model
Kim, Hyeon-Yeong ; Hwang, Cheol-Sang ; Gang, Seok-Man ; Lee, Gwang-Yang ;
Journal of Korea Water Resources Association, volume 31, issue 4, 1998, Pages 503~512
When various elements of water balance are displayed at several points of a river network, the runoff amounts at an estuary especially tidal influenced are affected from the elements. This problem can be solved by a model that can generalize and formulate the elements and simulate daily runoff and water requirement. The WWASS model was built using DIROM for the simulation of daily runoff and water requirement, and the water balance elements were modeled to be balanced at the each control point of river network. The model was calibrated, verified and applied to the watershed for the Saemankeum tidal land reclamation development project. It showed that the results from the streamflow simulation at the Mankyung and Dongjin estuary were acceptable for the design of the Saemankeum estuary reservoir.