Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of The Korean Society of Civil Engineers
Journal Basic Information
Journal DOI :
Korean Society of Civil Engeneers
Editor in Chief :
Volume & Issues
Volume 18, Issue 3_6 - Nov 1998
Volume 18, Issue 2_6 - Nov 1998
Volume 18, Issue 1_6 - Nov 1998
Volume 18, Issue 3_5 - Sep 1998
Volume 18, Issue 2_5 - Sep 1998
Volume 18, Issue 1_5 - Sep 1998
Volume 18, Issue 3_4 - Jul 1998
Volume 18, Issue 2_4 - Jul 1998
Volume 18, Issue 1_4 - Jul 1998
Volume 18, Issue 3_3 - May 1998
Volume 18, Issue 2_3 - May 1998
Volume 18, Issue 1_3 - May 1998
Volume 18, Issue 3_2 - Mar 1998
Volume 18, Issue 2_2 - Mar 1998
Volume 18, Issue 1_2 - Mar 1998
Volume 18, Issue 3_1 - Jan 1998
Volume 18, Issue 2_1 - Jan 1998
Volume 18, Issue 1_1 - Jan 1998
Selecting the target year
Numerical Analysis of Hydraulic Jump by the Flux Splitting Method
Oh, Seong-Taek ; Hwang, Seung-Yong ; Lee, Kil-Seong ;
Journal of The Korean Society of Civil Engineers, volume 18, issue 2_3, 1998, Pages 215~215
Upwind schemes based on the flux splitting method promise the stable solution for solving the hyperbolic partial differential equations with different characteristic directions. In these methods Roe's method and Steger and Warming method were selected for testing the applicability on the hydraulic jump. Their results were compared with the experiments of Gharangik and Chaudhry (1991). Two methods, employed in this study, simulated well the hydraulic jump regardless of their first order in accuracy. Two methods had little difference in prediction of location of hydraulic jump while Steger and Warming method gave relatively realistic results for predicting the length of hydraulic Jump.
Entrainment Across a Density Stratified Interface
Oh, Young-Min ;
Journal of The Korean Society of Civil Engineers, volume 18, issue 2_3, 1998, Pages 223~223
A floating bottomless containment has been considered to keep a freshwater separated from seawater in an estuary or coastal area. This system is advantageous to reduce a water deterioration by allowing water flowing underneath and costs less than a fixed structure system. The optimal design of the structural system and installation methods are necessary to carry out this project successfully, however, it is a prerequisite to study entrainment rate across a density stratified interface between the freshwater and the saltwater flowing underneath the bottomless containment in order to assess the function viability of such a system. Some earlier research works have considered this topic both theoretically and experimentally. In this study the commercial computational fluid dynamics modelling package called FLUENT. which is able to calculate turbulent motion. is used to simulate the entrainment phenomena and the results are compared with the earlier theoretical and experimental findings. The entrainment rate synthesised numerically in this study has been shown to be capable of yielding good agreement with the test data.
A Modeling of Daily Precipitation Series using the Poisson Cluster Process
Kim, Jae-Han ; Lee, Jung-Sik ; Lee, Jae-Joon ; Son, Kwang-Ik ;
Journal of The Korean Society of Civil Engineers, volume 18, issue 2_3, 1998, Pages 231~231
The precipitation occurrence process is modelled by the Neyman-Scott cluster process which is a stochastic model of point process. To analyze the cluster of the precipitation occurrence process in daily precipitation series, normalized spectrum of precipitation counts and log survivor function of interarrival time are applied by the Poisson process and Poisson cluster process. As the result of analysis of normalized spectrum and log survivor function Poisson cluster model is more fitted than Poisson model. The discrete probability distributions : TBD, TPD, TNBD, and LSD, are used to determine optimal probability distribution of the cluster size and the precipitation amounts of given wet day is estimated by the continuous probability distributions: Gamma, Pearson Type-III, Extremal Type-III. and 3 parameter Weibull distribution. It is shown that the cluster size is fitted by the TNBD in general. and the precipitation amounts is fitted by the TE3, PT3, Gamma in order.
Application of Hydraulic Model Experiment to Improve the Tranquility of Kampo Harbor
Kim, Se-Woong ; Chun, In-Sik ; Lee, Hong-Jae ;
Journal of The Korean Society of Civil Engineers, volume 18, issue 2_3, 1998, Pages 243~243
This experiment is intended to test the various layouts for the improvement of the tranquility of Kampo Harbor and to decide the best one through the analysis and comparison. The model of Kampo Harbor is an undistorted model with the Froude's similitude rule. For the quantitative comparison. the wave height ratios with respect to the deep water wave height are determined, which give the distributions of equal wave height ratios in each layout. The comparison is done for three different wave directions for which design waves are separately selected.
Runoff Model based on the Stream Path Type
Jeon, Min-Woo ; Cho, Won-Cheol ; Jung, Sae-Hee ;
Journal of The Korean Society of Civil Engineers, volume 18, issue 2_3, 1998, Pages 251~251
This paper represents a spatially distributed model to simulate the rainfall-runoff process based on a system analysis approach for the watershed system. Based on the Horton's stream order laws, the watershed can be divided into a number of subwatersheds according to the different stream path type The linear reservoir model was applied to the subwatersheds and the rainfall excess process of each subwatershed is represented by a unit step function. The Laplace transform of rainfall excess on all of the subwatersheds were substituted into the Laplace transform of the watershed system. Finally, the analytical model for the runoff hydrograph is obtained by taking the inverse of Laplace transform. Characteristics of the parameters for the derived rainfall-runoff model were analysed and this model was applied to Sansung station in Bocheong stream for verification.
Characteristics of Precipitation and River Water-Quality Variation by the Factor Analysis Method
Lee, Yong-Hwan ; Baek, Kyung-Won ; Han, Kun-Yeun ; Song, Jai-Woo ;
Journal of The Korean Society of Civil Engineers, volume 18, issue 2_3, 1998, Pages 263~263
Most of the studies for interpreting water quality in a river are performed based upon the data obtained on no-rainy period. But on rainy days, due to the inflow of nonpoint-pollution loads into river, the variations of river water quality are very complicate and water quality reaction time is relatively short. Therefore. the analysis performed based on the data collected during the long time period. which is monthly or annual average water quality data, leads to a wrong result. In this paper, in order to interpret the characteristics of rainfall and water quality variation, the hourly data at 4 monitoring stations of the Tama River at Tokyo in Japan collected from April 1995 to March 1996. was analyzed by the factor analysis method. Factor analysis reveals that the antecedent storm days and water quality can be grouped in same category.
Boundary Element Method for Predicting Breaking Waves on the Sloping Boundary
Chun, In-Sik ; Shim, Jae-Shul ; Lee, Hong-Sik ;
Journal of The Korean Society of Civil Engineers, volume 18, issue 2_3, 1998, Pages 277~277
In the present study a numerical method using boundary element method is developed to analyze nonlinear wave fields occurring on the sloping boundary. The kinematic free surface boundary condition is perfectly incorporated in the method, which can then be applied to the strongly nonlinear waves showing severe asymmetrical profile like plunging breakers. The application of the method shows that the wave evolution including breaking waves on a sloping boundary are well reproduced. Both the height and depth of the breaking waves appeared to overally agree with existing experimental results. The water particle velocities under breaking waves show their maximal values on the vertical side faced to the land. In a qualitative sense, the directional property of both the velocity and acceleration of the water particles also shows very similar pattern to that from linear wave theory.
A Study of System Development for the Detection of Toxic Materials into the Source of Water Supply
Lee, Hyung-Ki ; Lee, Young-Ho ;
Journal of The Korean Society of Civil Engineers, volume 18, issue 2_3, 1998, Pages 289~289
To secure clean water, we need to monitor water quality and detect out harmful materials, if any contained in the water. as early as possible. In general. fishes are believed to be more sensitive to water quality than human beings are to be. When fishes are moving slowly in a cluster, the water quality is believed to be good or normal enough. However, fishes keep afloat on the water or they behave wildly when poisonous materials are introduced into the water. This paper describes the system which visually inspects water quality by analyzing the motionality of fishes. The motionality features are defined by characterizing changes of behavioral patterns of fishes. These features are then used in making a fuzzy decision about the inclusion of toxic materials into the source of water supply. Tn order to verify the reproducibility of system, the sensitivity analyses for three types of toxic materials such as cyanide. phenol and chrome were performed and the quantitative test results could be obtained according to the change in types and concentration of toxic materials. The methodology described in this paper is expected to be reliable, and to enable us to make quick and accurate detection or assessment of hazardous chemicals contained in the water.
The Effects of Operating Parameters on In-Line Filtration
Choi, Suing-Il ; Hwang, Moon-Hyun ;
Journal of The Korean Society of Civil Engineers, volume 18, issue 2_3, 1998, Pages 299~299
The effect of flash mixing methods combined with various filter media composition on the direct filtration have been investigated. The strength of in-line mixing was measured by the headless casued by in-line mixer. Three mixers causing headless of 30 cm. 50 cm, and 90 cm have been used. Three variations of detention time from flash mixing to filter were 1. 5. and 10 minutes. Five media composition were 60 cm of sand, 50 cm anthracite above 25 cm sand. 50 cm anthracite above 30 cm sand, anthracite 30 cm above 30 cm sand, and 30 cm anthracite above 25 cm sand. Although the in-line mixer causing 90 cm of headless resulted in the longest filtration duration, the in-line mixer of 50 cm headless showed almost similar filtration duration. After flash mixing 1 minute detention time before filtration showed longer filtration than 10 minutes detention. Flocculation by slow mixing after flash in-line mixing produced big, settlable flocs resulting in the shorter filtration duration for all filter media combination. Among the media compositions. the longest filtration period has been observed at the composition of 50 cm anthracite above 30 cm sand.
Chlorine Decay in Water Distribution Network
Park, No-Suk ; Joo, Dea-Sung ; Park, Hee-Kyung ; Ahn, Chang-Jin ;
Journal of The Korean Society of Civil Engineers, volume 18, issue 2_3, 1998, Pages 307~307
To effectively maintain residual chlorine above 0.2mg/L. it is necessary to have more detailed and comprehensive understanding of the physico-chemical behavior of chlorine in the network. This study thus attempts to look at it and to build models for the chlorine decay in the network. Several parameters including iron, total organic carbon (TOC), temperature and time are related into the chlorine decay models by conducting the batch and simulated distribution system experiments. According to the experiment results, the initial concentration is shown to be negatively related to the concentration of chlorine and other parameters including the iron concentration, TOC. temperature and time positively to it. The prediction models are developed based on the results. For evaluation, they are compared to the Smith model proving of their superior capability and applicability.
Reuse of Wastewater using Microfiltration (MF) under Agitator-induced Flushing of Membranes and Intermittent Suction of Effluent
Song, Kyung-Guen ; Ahn, Kyu-Hong ; Hong, Jin-Mo ;
Journal of The Korean Society of Civil Engineers, volume 18, issue 2_3, 1998, Pages 317~317
This study investigated a new microfiltration wastewater-reuse system utilizing agitator-induced flushing of the membrane to prevent fouling. The system aimed at treating low-strength building wastewater by single-step, without adopting biological treatment concepts. A hollow fiber membrane module was immersed in the tank and permeate was filtered through the membrane by intermittent suction using a pump. In the tank, an agitator was operated at 350 nm, with clockwise (4 seconds) - stop (1 second) - counter-clockwise (4 seconds) rotation cycle. The microfilter membrane had a pore-size of
. For full-scale implementation. some key operational parameters such as flux and length of suction were studied. The optimal operational setting was determined to be 0.02m/hr flux, with 10-minute-suction and 2-minute rest permeate pumping cycle. Such setting was capable of 77 days of continuous operation. With chemical washing of the membrane every 3 months. long-term operation beyond several years would be possible. Effluent contained. in average, below 20mg/L of COD, below 3.5 mg/L of TOC, below 0.2NTU of turbidity, and nearly no suspended solids, and was adequate for the reuse of wastewater for secondary applications such as in toilet flushing.