• Title/Summary/Keyword: Outflow

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Runoff Analysis for Urban Unit Subbasin Based on its Shape (유역형상을 고려한 도시 단위 소유역의 유출 해석)

  • Hur, Sung-Chul;Park, Sang-Sik;Lee, Jong-Tae
    • Journal of Korea Water Resources Association
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    • v.41 no.5
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    • pp.491-501
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    • 2008
  • In order to describe runoff characteristics of urban drainage area, outflow from subbasins divided by considering topography and flow path, is analyzed through stormwater system. In doing so, concentration time and time-area curve change significantly according to basin shape, and runoff characteristics are changed greatly by these attributes. Therefore, in this development study of FFC2Q model by MLTM, we aim to improve the accuracy in analyzing runoff by adding a module that considers basin shape, giving it an advantage over popular urban hydrology models, such as SWMM and ILLUDAS, that can not account for geometric shape of a basin due to their assumptions of unit subbasin as having a simple rectangular form. For subbasin shapes, symmetry types (rectangular, ellipse, lozenge), divergent types (triangle, trapezoid), and convergent types (inverted triangle, inverted trapezoid) have been analyzed in application of time-area curve for surface runoff analysis. As a result, we found that runoff characteristic can be quite different depending on basin shape. For example, when Gunja basin was represented by lozenge shape, the best results for peak flow discharge and overall shape of runoff hydrograph were achieved in comparison to observed data. Additionally, in case of considering subbasin shape, the number of division of drainage basin did not affect peak flow magnitude and gave stable results close to observed data. However, in case of representing the shape of subbasins by traditional rectangular approximation, the division number had sensitive effects on the analysis results.

Evaluation of Ground Thermal Conductivity by Performing In-Situ Thermal Response test (TRT) and CFD Back-Analysis (현장 열응답 시험(TRT)과 CFD 역해석을 통한 지반의 열전도도 평가)

  • Park, Moonseo;Lee, Chulho;Park, Sangwoo;Sohn, Byonghu;Choi, Hangseok
    • Journal of the Korean Geotechnical Society
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    • v.28 no.12
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    • pp.5-15
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    • 2012
  • In this study, a series of CFD (Computational Fluid Dynamics) numerical analyses were performed in order to evaluate the thermal performance of six full-scale closed-loop vertical ground heat exchangers constructed in a test bed located in Wonju. The circulation HDPE pipe, borehole and surrounding ground formation were modeled using FLUENT, a finite-volume method (FVM) program, for analyzing the heat transfer process of the system. Two user-defined functions (UDFs) accounting for the difference in the temperatures of the circulating inflow and outflow fluid and the variation of the surrounding ground temperature with depth were adopted in the FLUENT model. The relevant thermal properties of materials measured in laboratory were used in the numerical analyses to compare the thermal efficiency of various types of the heat exchangers installed in the test bed. The simulation results provide a verification for the in-situ thermal response test (TRT) data. The CFD numerical back-analysis with the ground thermal conductivity of 4 W/mK yielded better agreement with the in-situ thermal response tests than with the ground thermal conductivity of 3 W/mK.

Various Meanings of Wolji Pond Construction in Shilla Dynasty (월지 조성 목적의 중의성(重意性) 고찰)

  • Hong, Kwang-Pyo
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.34 no.3
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    • pp.67-77
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    • 2016
  • This study was initiated from question raised on existing study achievement that purpose for Wolji construction simply was to build gardens. In this research, after raising a question on existing theory about the Wolji construction, another purpose of Wolji construction is investigated. Study result is as follows. First, two questions raised on Wolji construction are "Was Wolji constructed as a garden from the beginning?" and "Was Wolji region available land as now at time of creation?" However, it was verified that the purpose of Wolji construction was to use not as a garden but as a detention pond, and the land of such region was unserviceable at time of Wolji construction. Second, in terms of locations and Topography, it was confirmed that Wolji has a favorable condition for undercurrent function as it is positioned at the end point of flow path formed by gushout water spurting from the water flooded from Bukcheon, or low and wetland. Third, from hydraulic point of view, Bukcheon always has a possibility of flooding occurrence before completing river bank build up, and such flooding damage was curved at Guhwangdongwonji, and at Wolji once again in order to prevent the damage spread into the center of Wanggyeong. Fourth, from urban planning point of view, it was confirmed that urban functions were not established in Wolji region before Wolji construction, and urban planning was completed through the opening of roads and others, after Wolji construction. Fifth, it was confirmed that inflow and outflow device of Wolji, and vertical stone platform at western side of Wolji were the facilities to provide sufficient functions as detention ponds.

Geographical Characteristics and Patients' Determinants of Online Referrals : A Case Study of Choongbook, Korea (온라인 협진에 대한 지리적 특성과 환자의 결정에 관한 연구 : 충청북도 사례를 중심으로)

  • Park, Soo-Kyung
    • Journal of the Korean association of regional geographers
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    • v.17 no.5
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    • pp.617-637
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    • 2011
  • This study employs qualitative approaches to examining geographical characteristics and patients' determinants of online referrals in terms of regionalization. In this light, I conducted interviews with 20 patients receiving online referrals in Choongbook, Korea, and investigated their behaviors regarding these referrals between July and August 2009. I found that many patients who suffered from various levels of illness preferred tertiary care centers outside of Choongbook and did not enjoy their experience with the local medical institutions as the online referral service sites. This result might be because patients choose online referrals for psychological considerations such as quality and level of health care services, personal stakes in online referral service sites, acceptability and credibility of good tertiary care centers, and easy access to and use of medical institutions. Meanwhile, immediate benefits with regard to the technological value of online referrals, such as convenience, utility, and original purpose associated with regionalization, did not influence patients' decision-making. Therefore, the social and public networks affiliated with online referrals plus the effect of Korean medical laws play hostage to private decisions made by citizens, who prefer high-level medical institutions. Accordingly, the technological contribution of online referrals does not halt the outflow of patients from local, tertiary care centers. Especially, the existing health care system and patients' behaviors are deeply related to referrals in the online system. To protect regionalization, the improvement of health care services from the present state of affairs is required.

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Study on Phosphorus Removal in the Secondary Effluent by Flotation Using Microbubble Liquid Film System (미세기포 액막화 부상법을 이용한 하수 2차 처리수의 인 제거에 관한 연구)

  • Lee, Shun-Hwa;Kang, Hyun-Woo;Lee, Se-Han;Kwon, Jin-Ha;Jung, Kye-Joo
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.1
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    • pp.42-48
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    • 2012
  • In this study, experiment on phosphorus removal was performed by using microbubble liquid film flotation tank with microbubble module. After dissolving gas and liquid in dissolving tank, microbubble liquid film system created microbubbles in equal size under fixed low pressure. After being passed through $A_2O$ and m-$O_3$ process, secondary treatment wastewater was used as influent in phosphorus removal process. When the T-P concentration of influent was 2.89 mg/L, alum(8%, 30 mg/L) was injected into a microbubble flotation tank, the treatment resulted 94% of T-P removal rate. Remaining T-P concentration was less than 0.2 mg/L, which is in accord with the effluent quality standard. Seasonal variations in water temperature showed no differences in T-P removal property. When the inflow concentration of SS was 1.0 mg/L or more, it served as coagulation nuclei in the coagulation process. In that condition, average T-P removal rate was higher than 97%. When 50% of floated scum was returned, coagulator Al included in scum assisted the injected coagulator and maximized the coagulation efficiency of pollutant. In such treatment, the T-P concentration was measured as 0.18 mg/L and satisfied the outflow water quality standard, which is 0.2 mg/L or less.

A Study on Evaluation of Target Region for the Agricultural Non-point Sources Management (새만금 유역 농업비점오염원 관리를 위한 우선지구 선정연구)

  • Jang, Nam-Jung;Kim, Bo-Guk;Im, Seoung-Hyun;Kim, Tae-Kyun
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.1
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    • pp.23-31
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    • 2012
  • Measures against non-point sources pollution in Saemangeum watershed should be established to control water quality of Saemangeum lake, because non-point sources pollution discharge portions of BOD (Biological Oxygen Demand) and TP (Total Phosphorous) in the watershed were 68.4 and 61.4%, respectively. In this study, target regions for the non-point sources pollution control were selected to apply BMP (Best Management Practices) for the agricultural area of Saemanguem watershed in terms of TP that caused eutrophication at the lake. Target regions were selected by the NPSI (Non-point source index) that was calculated by the total 12 indexes at the steps of non-point source production, emission and outflow. Weights of the indexes were determined by the watershed management experts oriented AHP (Analytic Hierarchy Process) analysis. The target region was selected at the unit of Korean basic administrative district 'Dong/Li'. At the results of NPSI calculations through the GIS (Geographical Information System) tools, two sets of 5 regions were selected in the Man-kyung River and Dong-gin River. The main reason for the selected target regions was livestock activity in the district. The results of this study can be useful for implementing the reduction projects of agricultural non-point sources pollution to control water quality in Saemangeum lake.

Numerical Simulation for Net-water Flux of the Cross-sectional area in the Nakdong River Estuary (낙동강 하구역내 사주간의 단면유량플럭스 수치모의)

  • Yoon, Han-Sam;Lee, In-Cheol;Ryu, Cheong-Ro
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.8 no.4
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    • pp.186-192
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    • 2005
  • We investigated the deposition characteristics and mass transport flux estimation of the Nakdong estuary, Korea. To understand the effects of the tidal current circulation that influences estuary terrain changes, we used a 2D numerical model to map seawater circulation under three different situations, with the level of river flow being set as none or flood. The net-water flux of the cross-sectional area between sandbars (known as dung) was estimated. From our review of previous research, we know that the development of local sandbars shifted from the west to the east side of the estuary after the construction of the Nakdong River dike. Current development is occurring mostly at the Bakhap-dung near Tadea. The seawater circulation pattern over this large-scale area of tidal na is brings changes related to the quantity of the outflow from the Nakdong River. Based on the calculated results for the net-water flux of the cross-sectional area, we see very strong accumulation in local waters around Jangjiado, Bakhapdung, and Tadae under flood river flow conditions, but accumulation in local waters around Jinudo under the other states of flow. Consequently, in the Nakdong estuary, the main sensitive regions that are affected by changes in the flow of river discharge are the local waters around Jangiado, Bakhapdung, Tadae, and Jinudo.

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Numerical Model for Spreading of Cochlodinium Bloom in the Southern Coastal Waters in Korea (한국 남해안에서 Cochlodinium적조 확산모델)

  • Kwon Chul Hui;Cho Ku Dae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.6
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    • pp.568-577
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    • 2002
  • The spreading Cocuoainim polykikoides bloom in the southern coastal waters of Korea was simulated using numerical model including the physical processes of water flow and the chemical processes of increasing cell of C. polykikoides by uptake of dissolved nutrients. The circulation of sea water was simulated by two dimensional tide model reflecting the main four tidal components of $M_2,\;S_2,\;K_1,\;O_1$, and permanent current was driven by inflow/outflow across open boundaries. According to the result of model which tidal and permanent current were reflected simultaneously, eastward flows entering the southern waters from the western waters of Korea are dominant but westward flows are weak relatively. These result suggest that it is difficult for initial C. polykikoides bloom generated in the coastal waters of Goheung to move to the western coast of Korea through Jeju Strait. For spreading model of C. poiyhikoides, the range of generating distribution and the generating time of C. polykikoides bloom in coastal area are similar to those of observation data in the field. Wind is the most important factor in moving and distribution of red tide. Permanent current flowing eastward is also considered to be important factor and tidal current was a little influenced.

Design and Implementation of an Intelligent Medical Expert System for TMA(Tissue Mineral Analysis) (TMA 분석을 위한 지능적 의학 전문가 시스템의 설계 및 구현)

  • 조영임;한근식
    • Journal of KIISE:Software and Applications
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    • v.31 no.2
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    • pp.137-152
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    • 2004
  • Assesment of 30 nutritional minerals and 8 toxic elements in hair are very important not only for determining adequacy, deficiencies and unbalance, but also for assessing their relative relationships in the body. A test has been developed that serves this purpose exceedingly well. This test is known as tissue mineral analysis(TMA). TMA is very popular method in hair mineral analysis for health care professionals in over 46 countries' medical center. However, there are some problems. First, they do not have database which is suitable for korean to do analyze. Second, as the TMA results from TEI-USA is composed of english documents and graphic files prohibited to open, its usability is very low. Third, some of them has low level database which is related to TMA, so hairs are sent to TEI-USA for analyzing and medical services. it bring about an severe outflow of dollars. Finally, TMA results are based on the database of american health and mineral standards, it is possibly mislead korean mineral standards. The purposes of this research is to develope the first Intelligent Medical Expert System(IMES) of TMA, in Korea, which makes clear the problems mentioned earlier IMES can analyze the tissue mineral data with multiple stage decision tree classifier. It is also constructed with multiple fuzzy rule base and hence analyze the complex data from Korean database by fuzzy inference methods. Pilot test of this systems are increased of business efficiency and business satisfaction 86% and 92% respectively.

Review of the Revised 2019 Trade Secret Protection Act and Industrial Technology Protection Act : Focusing on Civil and Criminal Remedies (2019년 개정 영업비밀보호법 및 산업기술보호법에 대한 검토: 민·형사적 구제를 중심으로)

  • Cho, Yongsun
    • Korean Security Journal
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    • no.61
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    • pp.333-352
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    • 2019
  • In January and August 2019, there were amendments to the Unfair Competition and Trade Secrets Protection Act (UCPA) and the Industrial Technology Protection Act(ITPA). These amendments will contribute to technology protection. But these amendments need to be supplemented further. In the area of civil remedies, despite the introduction of treble damages in the case of the UCPA and ITPA, the provisions related to the submission of supporting data have not been maintained. Therefore, it is necessary to recognize the claim of the other party as true if it is maintained at the level of the revised Patent Act and the scope of submission of supporting data. And the enforcement of the case of compulsory submission for the calculation of damages, and the order of filing documents are not followed. ITPA, on the other hand, has introduced the compensation for damages, but there is no provision for estimating the amount of damages. Therefore, it is necessary to estimate the amount of lost profits, profits, and royalties. In the area of criminal remedies, both the UCPA and ITPA have raised the penalty, but the sentencing regulations are not maintained. In addition, although the recent outflow of technology has expanded beyond organizational deviations to organizational outflows, amendments need to be made in relation to the serious consequence for the punishment of related juristic persons, such as companies involved in it. It should be noted that Japan and the United States have corporate regulations and regulations. In addition, in relation to the confiscation system, Act on Regulation and Punishment of criminal proceeds concealment require that domestic defenses be confiscated by defense industry technology, while trade secrets and industrial technologies are confiscated only by "foreign" outflows, and an amendment is necessary.