• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.3
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• pp.3848-3859
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• 1975

The author attempted to find most suitable formulas for probable rainfall intensities with analysis and consideration for characteristics of rainfall intensities according to the short and long period return periods at Cheong-Joo district. Above mentioned formulas induced by this study can be contributed to the credibility of runoff estimation for urban sewerage system, drainage works in small catchment area and embankment works in the rivers. The results of this study are summarized as follows: 1 Calculation values by Gumbel-Chow method were selected as a mean values for the calculation of probable rainfall intensities according to return periods in the short period. 2. Calculations for probable rainfall intensities for long period are based upon to the result by Iwai's method. Talbot type, {{{{I= {a} over {t+b} }}}} is confirmed as a most suitable formula for probable rainfall intensities among calculation methods in the short periods at Cheong-Joo district. 4. Specific coefficient method, I24=RN24${\beta}$N was selected as a means of calculation for suitable formulas of probable rainfall intensities according to return periods in case of long period. 5. Runoff estimation with high credibility by rational formula can be anticipated by establishment for the most suitable probable rainfall intensities at Cheong-Joo district.

• Journal of Environmental Impact Assessment
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• v.10 no.3
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• pp.245-255
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• 2001

The management of water, both the quantity and the quality, has been one of the most important issues in the public investment and it is equally true in the field of sustainable development. Nevertheless, the jurisdiction of local governments has been delineated without much attention to the issue of the water management. In the planning of wide areas such as cities, countries, the metropolis, and the megalopolis, it is necessary to well arrange the geographical jurisdiction of local governments as a unit of region. The river water system, including small streams to large rivers, should be given its due share in the planning and jurisdictional delineation. The traditional concept of the local government's jurisdiction emphasizing the accessibility may be fading away. Instead, the efficiency of the public management would be the main concept in determining the jurisdiction of local governments. The river improvement, the waterworks, the sewage, the maintenance of water quality, the space of water recreation, are relatively important in the efficient management of that area. This paper argues for the equalization between the geographical jurisdiction of local governments and watersheds. To this end, I do case studies of the local governments areas such as Ri(里), Eup Myon(邑 面), Si Gun(市 郡), KyangyokSi Do(廣域市 道). The study interprets ARS will be one of the principles of land use and the reorganization of the local jurisdiction in the future as a geo-systematic and the eco-systematic criteria.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.862-864
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• 2013

Recently unstable weather condition has been going on then the damage by heavy rains, typhoons and stream flooding has been increasing continuously. In particular, the urban damage by flooding of rivers or roads has been occurred frequently. It could block all the transportation facilities within cities for restricting traffic. In this study, we suggest the method of utilization of the information about event and accident on roads through the real-time traffic information to cope with dangerous situation of roads.

• The Korean Journal of Ecology
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• v.24 no.4
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• pp.253-258
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• 2001

Land use pattern in the Wangsuk river watershed was investigated on the bases of physiognomic vegetation maps made from the aerial photograph interpretation and field check. Landscape structure was analyzed using a GIS program supported by ArcView. Landscape structure depended on the geographical position of the river, such as the upper, middle and lower river. Watersheds of the upper and middle rivers were dominated by forests composed of secondary forest and plantation. But agricultural fields dominated that of the middle and lower river. Urban area and agricultural fields increased in from the upper toward the lower river watersheds. In addition to, a transformation of agricultural pattern into an institutional agriculture was characteristic in the middle and lower river basins. Water qualities of the Wangsuk river were usually better in the order of the upper, middle, and lower river, but they were fluctuated according to the site. Such fluctuation would due to self-purification of the river and land use pattern of the watershed as the non-point source. In this viewpoint, a strategy to manage the water quality in the level of watershed is urgently required.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.1
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• pp.67-74
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• 2001

Now that importance of landscape planning unique to each area is emphasized, it is necessary to conduct landscape planning by taking advantage of natural environments unique to each ares, because its natural environments are regarded as one of the assets the area possesses. This study targets at Kawachinagano City, Osaka, one of the residential areas that I not only rich in natural and historical elements, but also has been rapidly growing. The purposes of this study are to evaluate change in landscape structure over time by analyzing relation between landform and pattern of expanding the built-up area at three time points of 1932, 1967, and 1994 with GIS (ARC/INFO 7.0.3, ARC/View 3.0 (ESRI)), as well as to make some suggestions for planning landscape unique to the area. Data on main ridges, sub ridges, main rivers, and other landform were read from the elevation map, and data on woodland, and parks and open spaces (having more than 3 ha area) were read from the existing land use map. The data were used to understand the natural structure of the city from topographic viewpoint. Next, the existing land use map prepared with data on the built-up area and urban axes consisting of roads and streets were overlaid on the elevation map in order to understand relation between pattern of expanding the built-up area and the natural structure.

• Journal of the Korean Institute of Landscape Architecture
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• v.24 no.4
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• pp.123-131
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• 1997

Since the industrial revolution. the growth of cities has been especially apid and the rate of ulbanization has been high. This urban development is encroaching on the natural environment because the cities are developed with not only residential estates, industrial area and buildings but also with infrastructure. The surface area of the city is sealed ,with pavement whereas nature is disturbed and modified. The hydrological cycle in the city is inf1uenced by the change of land use I. e., from forest to agricultural land, talc draining of wetlands and above all the increase of built-up areas. The surface retention and interception of precipitation in the city is reduced. because the surface area is now smooth and solid. The characteristics of the hydrological cycle in the city are increased runoff, reduced evapotranspiration and infiltraction . We have too much faith in technology although it may cause more unforseen problems. We build more river banks and 'emulation dams and straighten rivers and streams in order to protect ourselves from disasters.. However. the results of hose developments are often higher$.$ water levels, the disturbance of aquatic ecosystems and the reduction of biodiversity. Therefore, we should examine problems from the hydrological cycle in cities and study a natural system as close cities to nature as possible. This paper shows the problems caused by the hydrological cycle in the city. The ecology-oriented method and design must be used in order to protect our environment from dicturbance.

• Journal of Environmental Impact Assessment
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• v.20 no.3
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• pp.357-365
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• 2011

The QUAL2K has the same basic characteristics as the QUAL2E model, which has been widely used in stream water quality modeling; in QUAL2K, however, various functions are supplemented. The QUAL2Kw model uses a genetic algorithm(GA) for automatic calibration of QUAL2K, and it can search for optimum water quality parameters efficiently using the calculation results of the model. The QUAL2Kw model was applied to the Gangneung Namdaecheon River on the east side of the Korean Peninsula. Because of the effluents from the urban area, the middle and lower parts of the river are more polluted than the upper parts. Moreover, the hydraulic characteristics differ between the lower and upper parts of rivers. Thus, the river reaches were divided into seven parts, auto-calibration for the multiple reaches was performed using the function of the user-defined automatic calibration of the rates worksheets. Because GA parameters affect the optimal solution of the model, the impact of the GA parameters used in QUAL2Kw on the fitness of the model was analyzed. Sensitivity analysis of various factors, such as population size, crossover probability, crossover mode, strategy for mutation and elitism, mutation rate, and reproduction plan, were performed. Using the results of this sensitivity analysis, the optimum GA parameters were selected to achieve the best fitness value.

• Environmental Engineering Research
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• v.18 no.1
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• pp.9-20
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• 2013

In this paper, the rainfall elasticity of streamflow was estimated to quantify the effects of climate change on 5 river basins. Rainfall elasticity denotes the sensitivity of annual streamflow for the variations of potential annual rainfall. This is a simple, useful method that evaluates how the balance of a water cycle on river basins changes due to long-term climate change and offers information to manage water resources and environment systems. The elasticity method was first used by Schaake in 1990 and is commonly used in the United States and Australia. A semi-distributed hydrological model (SLURP, semi-distributed land use-based runoff processes) was used to simulate the variations of area streamflow, and potential evapotranspiration. A nonparametric method was then used to estimate the rainfall elasticity on five river basins of Korea. In addition, the A2 (SRES IPCC AR4, Special Report on Emission Scenarios IPCC Fourth Assessment Report) climate change scenario and stochastic downscaling technique were used to create a high-resolution weather change scenario in river basins, and the effects of climate change on the rainfall elasticity of each basin were then analyzed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.3
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• pp.219-227
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• 2021

Numerical simulation with Hwang's scheme, which can analyze shallow-water flow over discontinuous topography, was compared with a laboratory experiment of flooding on a perpendicular floodplain with dam-break flows. The simulation results were in good agreement with the results measured in an experimental flume with a reservoir, channel, and floodplain. The wetting and drying process on a perpendicular floodplain with a dam-break flow was particularly well simulated. The difference in simulation results according to the type of flow resistance was insignificant. The results of this study are expected to improve the accuracy of predicting inundation in urban rivers.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.3
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• pp.62-74
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• 2010

This study aims to examine what factors citizens value in urban parks and green spaces in terms of usage and aesthetic value and to find ways to deal with the changing patterns of user satisfaction for these various green elements. To achieve this, the study developed a dynamic model employing a transactional approach to evaluate environmental quality for 1999 and 2007 in Anyang City as well as a conceptual model of parks and greens satisfaction. This study relied on an empirical study method including the 1999 and 2007 green conditional survey and citizen questionnaires totaling 573 in the year 1999 and 982 in the year 2007. As a result, first, the factor 'urban parks' is the most important factor and 'cityscape' is the second most important factor in parks and greens satisfaction(PGS). Second, PGS in turn causes environmental quality satisfaction(EQS), which is related to two items--'urban livability' and 'aesthetic quality'--in the model. This means that PGS is the intervening variable of urban livability. Third, the factor analysis resulted in six factors: cityscape, urban green, linear facilities, urban parks, riverside green, and urban forest. 'Riverside green' emerged as a factor in 2007 as a result of public participation in the 'Anyang River Revitalization Project'. Fourth, through a transactional view, the environmental changes result in either a change in or stability of public attitude. The levels of satisfaction were elevated but patterns of satisfied-unsatisfied items remained unchanged for most factors. The perception of riverside a greenway and linear surface facilities(pedestrian walkways, biking and jogging trails, etc.) have changed positively. PGS changed significantly in 2007, as a result of urban events and development, including parks, rivers and greenways which were built through the joint effort of the local government and civic participation.