• Journal of the Korean Geophysical Society
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• v.2 no.2
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• pp.91-99
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• 1999

A high-resolution seismic profile acquired across the northeastern boundary of the Pungam Basin, one of the Cretaceous sedimentary basins in Korea, has been interpreted to delineate subsurface geological structures across the basin boundary. We identified boundary faults and unconformity surfaces of the basin and divided sediment body into three seismic depositional units (Units I, II, and III from youngest to oldest). Inferred from fault geometry and type, northeastern part of the Pungam Basin has been formed by a strike-slip fault whereas the normal faults near the boundary were formed by transtensional movement along a fault zone. A 350-400 m thick sediment layer is overlying the Precambrian gneiss. Bedding planes of Unit III are dipping westward and are closely related to an anticline in the acoustic basement. Unit II is also tilted westward, suggesting that the eastern part of the fault zone was uplifted after deposition of lower part of the sedimentary body. Afterward, the uplifted sediment layers were eroded and transported to the western part of the basin. Chaotic reflection pattern of sedimentary Units II and III may suggest that strike-slip movement along the fault zone deformed basin-filled sediments.

• Journal of Korean Society of Water and Wastewater
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• v.14 no.3
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• pp.240-250
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• 2000

In this study, DWTP Advisor developed from U.S. EPA was adapted for performance assessment in small water treatment plant and studied for improvement advice about the problem. From results of performance assessment, the ability of each major unit process meets to Peak Instantaneous Flow(PIF) as Type I (above 95% of PIF) in N WTP. But, outlet condition in the sedimentation basin are permitting the loss of solids from the basin and the lack of proper solids removal is degrading the performance in N WTP. From results of the hydraulic analysis using fluoride tracer, flow rate in sedimentation basin is rapidly more lower than upper. The Reynolds number, Re, and Froude number, Fr which are used to predict flow condition in sedimentation basin is calculated to be 3159.98 and $2.06{\times}10^{-7}$, respectively. There is possibility of occurrence of short-circuiting and turbulence. Also, the different type of effluent trough makes unstable flow in sedimentation basin and increases carry-overing of sedimented solids.

• Journal of Korea Water Resources Association
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• v.43 no.6
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• pp.559-569
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• 2010

This study proposes an empirical method for estimating the concentration time and storage coefficient of a basin using the Nash unit hydrograph. This method is based on the analytically derived concentration time and storage coefficient of the Nash model. More fundamentally, this method recursively searches convergent number of linear reservoirs and storage coefficient of linear reservoir representing the basin given. This method is to overcome the problem of HEC-HMS to use an optimization technique to estimate the basin concentration time and storage coefficient. The proposed method was applied to the Bangrim station of the Pyungchang river basin, also found to estimate physically reasonable values.

• Journal of Korea Water Resources Association
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• v.42 no.1
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• pp.75-92
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• 2009

The development of the method for flood runoff analysis representing Korean mountain basins have been one of big concerns for Korean hydrologists for several decades. Several traditional methods dealing with unit hydrograph have been restricted to be used in Korea basins, because of its drawbacks due to its originality from other countries and the uncertainties of control parameters as well as its linearity assumption between rainfall and runoff relationship. In this paper, several geomorphological similarity relationships for Korean mountain basins was developed by using the experimental data over 40 Korean basins. Then those were applied directly to geomorphological unit hydrograph theory to meet Korean geomorphological unit hydrograph. The developed method was applied to Andong Dam basin. The results show the applicability and simplicity of the developed Korean geomorphological unit hydrograph generally for Korean mountain basins in future. It might be needed for more validations and applications of this method over Korean regions.

• Journal of Environmental Impact Assessment
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• v.22 no.6
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• pp.557-568
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• 2013

In this study, Calculated the nonpoint sources(NPS) load per unit area about various rainy events in vineyard of Nakdong River basin. NPS monitoring and calculation for NPS load per unit area were estimated from 'Investigation method of precipitation discharge(National Institute of Environmental Research, 2007)'. The evaluation of applicability for NPS load per unit by compared with prior research data and Total Maximum Daily Load(TMDL) data. Five target areas were each $2000m^2$, $1800m^2$, $1943m^2$, $2484m^2$, $864m^2$ and located in Gyeongsangbukdo Gyeongju, Gyeongsangbukdo Sangju, Gyeongsangnamdo Hapcheon in Korea. Since fruits were the only crop on the target area, the characteristics of stormwater discharge at survey sites could be evaluated independently. A total of 115 rainfall events in the Orchard area during five years(2008-2012) was surveyed, and 38 of them became stormwater discharge. In the Nakdong River watershed, average of event mean concentrations(EMCs) in Orchard area for biochemical oxyzen demand(BOD), Chemical oxyzen demand(COD), total nitrogen(T-N), total phosphorus(T-P) were 2.0mg/L, 10.1mg/L, 3.195mg/L, 0.578mg/L, respectively. NPS load per unit area in Orchard area showed BOD : $2.0kg/km^2{\cdot}day$, COD : $10.2kg/km^2{\cdot}day$, T-N : $3.220kg/km^2{\cdot}day$, T-P : $0.606kg/km^2{\cdot}day$.

• Spatial Information Research
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• v.14 no.1 s.36
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• pp.15-27
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• 2006

This paper is about the threshold discharge computation using GIUH(Geomorphoclimatic Instantaneous Unit Hydrograph) on ungauged small basin. GIUH is one of the possible approaches to predicting the hydrograph characteristics. This study is calculated the various ways which are hydrologic characteristics, bankfull flows, unit peak flows(the Clark, the Nakayasu and the S.C.S) as well as threshold runoffs on about $5km^2$ scale at Kyungbuk gampo in subbasin. We are estimated propriety that peak discharge calculated the GIUH from acquiring data by GIS(Geographic Information System) compared to observed peak discharge. And, the threshold discharge was calculated by NRCS(Natural Resources Conservation Service) for a flash flood standard rainfall.

• Journal of Environmental Impact Assessment
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• v.17 no.1
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• pp.47-56
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• 2008

Total Maximum Daily Load(TMDL) is a core basin management system to assign total emissions of pollutants to unit basin and emission source within a limit of the target water quality and to secure sustainability. considering "Environment and development" together. By current technical guidance of TMDL, the water quality in the riverbed of which the target water quality is noticed, must achieve the target; and the water quality standard for evaluating achievement of the target should be prescribed as non-excessive probability quality of water on the basis of the pertinent water quality documents. Therefore, the study calculated the target water quality by each unit basin which the target water quality must be noticed through the analysis of probability for water quality documents in rivers at the time of establishing a plan, and the study evaluated the achievement possibility of the target water quality by analyzing and comparing the target water quality plan with the standard water quality to evaluate the achievement of the target water quality. As the result, applying the proposed method to Mihocheon River system, it is concluded that selected the target water quality (Each BOD 3.3mg/1 and BOD 3.0mg/1) in Miho A and Musim A is available. Of course, it showed that the target water quality: BOD 2.5mg/1 in Miho A and BOD 3.0mg/1 in Musim A, could be achieved if the small reduction in B unit area was implemented.

• Journal of Korean Society for Geospatial Information Science
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• v.14 no.2 s.36
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• pp.15-22
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• 2006

Runoff Characteristics has been Analysis Using geomorphologic Instantaneous Unit Hydrograph(GIUH) and geomorphoclimatic unit hydrograph(GCUH) on an ungaged vary small basin about $5km^2$ scale in Kyungbuk gampo area. First, we estimated hydrology Factor using Geographic Information System(GIS) tool and then, calculated the characteristic velocity using the real rainfall-runoff data. It is compared with several velocities derived from GCUH theory and several other concentration time formulae. Kerby and Braby-Williams seems to be more applicable as characteristic velocity formula. Second, We compared the GCUH peak discharge with the probable flood, also compared the unit hydrograph as like the Clark, the Nakayasu and the S.C.S and GCUH with the observed discharge using the real rainfall events. The comparison results showed that GCUH could be applicable on an ungaged vary small basin. We expected that the result can be used as for estimation of a flash flood standard rainfall as well as emergency management plan.

• Journal of the Korean association of regional geographers
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• v.12 no.2
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• pp.202-214
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• 2006

In this paper Gumho drainage basin is divided into six geomorphic units (Bohyeon, Palgong, Biseul mountainous areas and Yeongcheon, Gyeongsan, Daegu basin), and physical geographical background and distributional characteristics of geotourism resources in each geomorphic unit are examined. Most(32 sites, 78%) of geotourism resources in Gumho basin reflect geomorphological environment, rest(7 sites, 17%) of them reflect geological environment. There are three geomorphological resources in Bohyeon mountainous areas, eight geomorphological resources in Palgong mountainous areas, and five geomorphological resources and one cultural resource in Biseul mountainous areas. There are two geomorphological resources, one geological resource, one biological resource, and two cultural resources in Yeongcheon basin. Among them one biological resource and and one cultural resource reflect local geomorphological environment. In Gyeongsan basin are there one geomorphological resource, three geological resources, and one biological resource, but one biological resource reflects local geomorphological environment. There are eight geomorphological resources, two geological resources, and three biological resources in Daegu basin. But two biological resources among them reflect local geomorphological environment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3B
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• pp.241-251
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• 2006

This study analyzed the topographical characteristics by extracting property factors of stream (stream order, number of stream, stream length, mean stream length) and property factors of basin (basin area, basin length, total stream length, total number of stream, basin mean width, form factor, maximum stream order, basin density, stream frequency, relief ratio, mean elevation, mean, slope, maximum elevation) from DEM (digital elevation model) and stream network generated by 1:5,000 NGIS (national geographical information system) data for the Bukhan-river basin. In addition, topographical factors for upper, mid stream and lower stream were analyzed and the mutuality of the factors by linear and nonlinear regression curve was identified.