• Title/Summary/Keyword: Inflows

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Adaptation Capability of Reservoirs Considering Climate Change in the Han River Basin, South Korea (기후변화를 고려한 한강유역 저수지의 적응능력 평가)

  • Chung, Gunhui;Jeon, Myeonho;Kim, Hungsoo;Kim, Tae-Woong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.5B
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    • pp.439-447
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    • 2011
  • It is a main concern for sustainable development in water resources management to evaluate adaptation capability of water resources structures under the future climate conditions. This study introduced the Fuzzy Inference System (FIS) to represent the change of release and storage of reservoirs in the Han River basin corresponding to various inflows. Defining the adaptation capability of reservoirs as the change of maximum and/or minimum of storage corresponding to the change of inflow, the study showed that Gangdong Dam has the worst adaptation capability on the variation of inflow, while Soyanggang Dam has the best capability. This study also constructed an Adaptive Neuro-Fuzzy Inference System (ANFIS) for the more accurate and efficient simulation of the adaptation capability of the Soyanggang Dam. Nine Inflow scenarios were generated using historical data from frequency analysis and synthetic data from two general circulation models with different climate change scenarios. The ANFIS showed significantly different consequences of the release and reservoir storage upon inflow scenarios of Soyanggang Dam, whilst it provides stable reservoir operations despite the variability of rainfall pattern.

Transfer of Marketing Knowledge within Multinational Corporations and Its Impact on Performance: Moderating Effects of Absorptive Capacity, Socialization, and Local Knowledge

  • Lee, Byung-Hee
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.4
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    • pp.277-306
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    • 2008
  • Knowledge1 is considered to be a key element of understanding how organizations gain and sustain competitive advantages. But very few firms are capable of creating the requisite knowledge and thus, firms should acquire and exploit new knowledge through knowledge transfer processes. The empirical part of this study involves examining relationships among adaptability of knowledge and knowledge transfer and marketing performance and testing the moderating roles of absorptive capacity, socialization and local marketing knowledge. This study is organized as follows: (1) Previous literature on knowledge, knowledge transfer and absorptive capacity is summarized, followed by the development of hypotheses derived from the knowledge-based view and absorptive capacity. (2) The hypotheses are tested with data collected from MNCs' subsidiaries performing marketing activities in Korea.Thestudyisclosedwithfindings,implications,andconclusions. Following six research hypotheses are drawn from literature review in related areas: H1: Adaptability of knowledge transferred from the MNCs' headquarters and other subsidiaries is positively associated with knowledge inflows into the receiving subsidiary. H2: The level of marketing knowledge transferred from the MNCs' headquarters and other subsidiaries is positively associated with marketing performance of the receiving subsidiary. H3: Increases in potential absorptive capacity will enhance the relationship between adaptability of knowledge and the level of marketing knowledge transfer. H4: Increases in realized absorptive capacity will enhance the relationship between the level of knowledge transfer and marketing performance of the receiving subsidiary. H5: Increases in socialization activity among the headquarters and subsidiaries will enhance the relationship between adaptability of knowledge and the level of marketing knowledge transfer. H6: Increases in the level of locally developed marketing knowledge will enhance the relationship between the level of knowledge transfer and marketing performance of the receiving subsidiary. The research framework that illustrates the proposed hypotheses is presented in figure 1. The unit of analysis for this study is knowledge transfer from the MNCs' headquarters and other subsidiaries to their subsidiaries operating in South Korea. The population for this study consists of subsidiaries established either as joint ventures or as wholly-owned subsidiaries. A group of 603 foreign firms were drawn from diverse industry organizations and business societies. After personal contact, telephone, fax, and e-mail to request that the respondents complete the questionnaire, 282 valid questionnaires from 133 initial sample companies were collected. The results of the empirical analyses significantly support all of the proposed hypotheses except hypothesis 3. Adaptability of external knowledge promotes knowledge transfer and the relationship is moderated by a firm's potential knowledge absorptive capacity. On the other hand, knowledge transfer improves a firm's marketing performance and a firm's realized knowledge absorptive capacity and local marketing knowledge moderate the relationship. The theoretical and practical implications of the findings in this study are as follows: (1) firms must take seeking, transferring, sharing and exploiting of external knowledge into serious consideration, while simultaneously creating knowledge to support the necessary business operations, remain competitive, and achieve superior performance. (2) Firms should continuously seek to develop their knowledge absorptive capacity (both potential and realized capacity) to absorb, learn and utilize valuable external knowledge. (3) Firms should emphasize not only absorptive capacity, but also development of local knowledge. Firms with strong absorptive capability and local knowledge can learn and transfer more external knowledge, which can be translated into greater levels of competence and performance.

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Outlook of Discharge for Daecheong and Yongdam Dam Watershed Using A1B Climate Change Scenario Based RCM and SWAT Model (A1B기후변화시나리오 기반 RCM과 SWAT모형을 이용한 대청댐 및 용담댐 유역 유출량 전망)

  • Park, Jin-Hyeog;Kwon, Hyun-Han;No, Sun-Hee
    • Journal of Korea Water Resources Association
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    • v.44 no.12
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    • pp.929-940
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    • 2011
  • In this study, the future expected discharges are analyzed for Daecheong and Yongdam Dam Watershed in Geum River watershed using A1B scenario based RCM with 27 km spatial resolutions from Korea Meteorological Agency and SWAT model. The direct use of GCM and RCM data for water resources impact assessment is practically hard because the spatial and temporal scales are different. In this study, the problems of spatial and temporal scales were settled by the spatial and temporal downscaling from watershed scale to weather station scale and from monthly to daily of RCM grid data. To generate the detailed hydrologic scenarios of the watershed scale, the multi-site non-stationary downscaling method was used to examine the fluctuations of rainfall events according to the future climate change with considerations of non-stationary. The similarity between simulation and observation results of inflows and discharges at the Yongdam Dam and Daecheong Dam was respectively 90.1% and 84.3% which shows a good agreement with observed data using SWAT model from 2001 to 2006. The analysis period of climate change was selected for 80 years from 2011 to 2090 and the discharges are increased 6% in periods of 2011~2030. The seasonal patterns of discharges will be different from the present precipitation patterns because the simulated discharge of summer was decreased and the discharge of fall was increased.

Analyzing Spatial Pattern by moving Factors of out-migration people Related moving to the Provinces of Capital Region Firms (수도권 유출인구의 공간적 패턴분석 및 이동영향 요인 분석 - 수도권 기업의 지방이전과 관련하여 -)

  • Hong, Ha-Yeon;Lee, Kil-Jae
    • Journal of Cadastre & Land InformatiX
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    • v.44 no.2
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    • pp.155-175
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    • 2014
  • This study targets to recognize needs of spatial pattern analysis and to draw the relationship between relocation of Capital Region firms and population outflow in Capital Region through the regression analysis. The population outflow in Capital Region has moved to and around Yesan-gun and Asan-si. Also, such outflow is found to compose mostly one or two household members for their jobs. In addition to this study has analyzed to find effect factors through the Geographically Weighted Regression. The results of the analysis has confirmed that the most decisive factors affecting population flow from Capital Region to Chungcheongnam-do were population factors and transportation factors and others. Thus, the below policy implications could be derived and also may be applied toward Sejong City which are currently experiencing the relocating of Public sectors and new constructions. Firstly, the effect of Capital Region firms movement on population inflows could be better observed in small-scale towns like "kun" than larger-scale towns like "si.". On the other hand, people in Capital Region moved to larger-scale towns like "si" unlike the Capital Region firms. This difference implicates that people select their residence according to not only their jobs but also residential environment. Secondly, moving people from Capital Region to another region for their jobs are expected to appear more in a form of family units rather than individual units. Sejong city, where public organizations are being relocated, should recognize this particular Chungcheonnam-do phenomenon and be prepared to be more effectively used in perspectives of land use as well as urban planning.

Analysis of RCSTP And MWTP Pollutants Treatment Efficiency in Bong-Hwa Gun (봉화군 마을하수도 및 하수처리장의 오염물질 처리 효율 분석)

  • Park, Minsoo;Im, Jiyeol;Gil, Kyungik
    • Journal of Wetlands Research
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    • v.19 no.1
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    • pp.69-79
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    • 2017
  • Protected area of water for supply source is located mostly of rural area in Korea. Normally, sewage treatment system is poor to manage in rural, because low population and density. Rural area need sewage treatment system to supervise supply source of water. In this study, analysis on operation result of 4 RCSTP and MWTP is located at the rural area. Higher concentration of pollutant were inflows to MWTP than RCSTP, and effluent quality standard is satisfaction. However, RCSTP effluent pollutant concentrations was researched higher than MWTP. The organic matter(BOD, COD) were about 5% of a high treatment efficiency to a median. The nutrient(T-N, T-P) were detected Up to high 30%. Also, we analyzed to effect reactor operational parameters on the pollutant treatment efficiency like mixed liquer suspended solid(MLSS), dissolved oxygen(DO) and sludge retention time(SRT). As a result, pollutant treatment efficiency showed fluctuation in accordance with operating condition. Thus, it is necessary to manage the reactor operation condition for management of rural area sewage treatment.

Automatic Calibration of Storage-Function Rainfall-Runoff Model Using an Optimization Technique (최적화(最適化) 기법(技法)에 의한 저유함수(貯留函數) 유출(流出) 모형(模型)의 자동보정(自動補正))

  • Shim, Soon Bo;Kim, Sun Koo;Ko, Seok Ku
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.12 no.3
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    • pp.127-137
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    • 1992
  • For the real-time control of a multi-purpose reservoir in case of a storm, it is absolutely necessary to forecast accurate flood inflows through a good rainfall-runoff model by calibrating the parameters with the on-line rainfall and water level data transmitted by the telemetering systems. To calibrate the parameters of a runoff model. the trial and error method of manual calibration has been adopted from the subjective view point of a model user. The object of this study is to develop a automatic calibration method using an optimization technique. The pattern-search algorithm was applied as an optimization technique because of the stability of the solution under various conditions. The object function was selected as the sum of the squares of differences between observed and fitted ordinates of the hydrograph. Two historical flood events were applied to verify the developed technique for the automatic calibration of the parameters of the storage-function rainfall-runoff model which has been used for the flood control of the Soyanggang multi-purpose reservoir by the Korea Water Resources Corporation. The developed method was verified to be much more suitable than the manual method in flood forecasting and real-time reservoir controlling because it saves calibration time and efforts in addition to the better flood forecasting capability.

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Dynamic Changes of Dissolved Oxygen during Summer Monsoon (하절기 장마동안 용존산소의 역동적 변화)

  • An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.33 no.3 s.91
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    • pp.213-221
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    • 2000
  • Seasonal oxygen content and deficit rates were evaluated from 17 sites of Taechung Reservoir during 1993${\sim}$1994. In 1993, river inflows peaked during the monsoon in July${\sim}$August and disrupted thermal stratification and anoxic layers in the headwaters, thereby confining the anoxia to the mid-lake and downlake reach. The volume of anoxic water with < 4 mg/l DO comprised only < 10% of the total lake volume in this period. In contrast, during monsoon 1994, 85% of total lake volume was subject to hypoxic conditions with oxygen concentrations < 30% saturation, resulting in massive fishkills (Hypomesus olidus). Relative areal oxygen deficit (RAOD) was -0.024mg O$_{2}$cm$^{-2}$d$^{-1}$ during monsoon 1993, whereas it rapidly decreased at the rate of 0.080mg O$_{2}$cm$^{-2}$d$^{-1}$ during monsoon 1994. Anoxic factor (AF) showed a same interannual pattern as the RAOD and was greater >50 d in 1994 (76.5 d) than 1993 (21.3 d). Thus, the reservoir showed a river-characteristics (6${\sim}$11 mg/l DO) in 1993 while lacustrine conditions (<4mg/l DO) dominated in 1994. Regression analysis showed that the variation of summer DO was mostly determined (R$^{2}$=0.99, p<0.0001) by inflow. These findings suggest that the primary factor regulating the oxygen content in this system during summer is an intensity of the monsoon rain.

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Land Bank Bond for the Diversification of Land Bank Financing Resources: Comparative Case Study and the Improvement of Legal, Accounting System (토지비축의 안정적 재원조달을 위한 토지은행채권 도입방안: 사례 비교를 통한 법·제도·회계처리 개선방안을 중심으로)

  • Lee, Jong-Kwon;Choi, Eun-Hee
    • Land and Housing Review
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    • v.3 no.4
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    • pp.333-341
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    • 2012
  • The financial resources for public land banking enacted by Public Land Banking Act (2009) are LH (Korea Land and Housing Corporation) contributions, LH Bond, Land Bank revenues, etc. But, in real, the efficient funding resource is mainly LH bond. In these days, LH has experienced deep financial distress, and difficulties in issuing it's bond. Therefore, Land Banking project also has been inactivated because of poor financial resources. As Land Banking project depending its financial resources mainly on LH Bond does not have financial sustainability, it is necessary to reform the fundamental funding structure. This is the starting point for the topic of this paper. This paper suggests to reform the funding structure, and to introduce Land Bank Bond guaranteed by Government, and also to modify the accounting method of Land Bank to separate the Land Bank accounts with LH accounts. The funding structure reform can be summarized as follows; In early stage of the Land Banking project, sufficient government support by guaranteeing the Land Bank Bond is necessary. Gradually, the portion of LH's contribution can be increased in company with LH's financial distress being solved and administration being normalized. When the project reached on the stage of maturity, cash inflows by selling the reserved land can exceed the cash outflows for reserve new land. To introduce the Land Bank Bond guaranteed by government, the Public Land Banking Act (2009) should be revised. Along with this, to modify the accounting method of Land Bank, the rule for public enterprise accounting system must be partially revised.

Characteristic Community Dynamics of Phyto- and Zooplankton in a Shallow Eutrophoic Reservoir (얕은 부영양 저수지의 동${\cdot}$식물플랑크톤 군집변화 특성)

  • Kim, Ho-Sub;Kong, Dong-Soo;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.38 no.1 s.110
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    • pp.18-29
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    • 2005
  • This study was conducted to understand seasonal dynamics of phyto- and zooplankton communities in a shallow eutrophic reservoir (Shingu reservoir) from November 2002 to February 2004. Cyanophyceae dominated throughout the year, except for spring (March ${\sim}$ May) when Bacillariophyceae (Melosira varians) and Chlorophyceae (Dictyosphaerium puchellum) were dominant. The change of dominant species in Cyanophytes occurred in June and December 2003, and the increase of phytoplankton cell density in July and November was observed when the P loading through two inflows was high. In May, Oscillatoria spp. and Aphanizomenon sp. were dominant, but replaced by Microcystis spp. in the end of May. Dominant Microcystis spp. sustained until December and shifted to Oscillatoria spp. and Aphanizomenon sp. TN/TP ratio ranged from 13 to 46 (Avg. $27{\pm}6$) from June to December when cyanobacteria (Microcystis spp.) dominated. Rotifers such as Keratella cochlearis, Keratella valga, Polyarthra spp., Conochilus unicornis, Pompholyx complanata dominated in average 67.8% of the zooplankton community. Abundance of zooplankton was the highest in June 2003, when Pompholyx complanata (12,388 ind $L^{-1}$) was dominant. In May, the significant increase of Conochilus unicornis biomass ($1,048{\pm}28\;{\mu}g\;C\;L^{-1}$) was observed with distinct improvement of transparency ($Z_{eu}/\;Z_m=\;1.1$). These results suggest that the seasonal variation of phytoplankton communities in this reservoir are to be understood as results of multi-interactive factors such as temperature, light condition and nutrients, and small-sized rotifers as important predator.

A Time Variable Modeling Study of Vertical Temperature Profiles in the Okjung Lake (옥정호의 연직 수온분포에 관한 시변화 모델 연구)

  • Park, Ok-Ran;Park, Seok-Soon
    • Korean Journal of Ecology and Environment
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    • v.35 no.2 s.98
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    • pp.79-91
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    • 2002
  • A time variable modeling study was performed for seasonal variations of vertical temperature profiles in the Okjung Lake located in upstream of the Sumjin River. Based on the model structure of the US Army Corps of Engineer's CE-QUAL-W2, the lake was divided into 3 branches, 50 longitudinal segments and 49 vertical layers and vertical profiles of water temperature and current velocity were simulated over one year. The model results were calibrated and verified against vertical profiles of water temperature measured every month from March 1998 to February 1999 at 5 different locations. The model results showed a good agreement with the field measurements. The hydrologic balance during this period was validated by comparing the simulated values of surface elevation level with the measured data. There was some discrepancy in July data between the model results and the fleld measurements. This could be attributed partially to the inadequacy of the model to the highly hydrodynamic nature of water body and partially to the lack of accuracy in local atmospheric temperature data during summer monsoon period. The model results have shown that there was no seasonal over-turn in most part of the Okjung Lake, where water temperature maintained above $4^{\circ}C$ over one year. In the upstream shal-low area (depth<20 meter), however, temperature at surface layer fell below $4^{\circ}C$ and water was frozen such that slight over-turn would occur during winter period. From this study, we concluded that the Okjung Lake is oligomictic. This conclusionis significantly different from the general pattern that the lakes located from $20^{\circ}C$ to $40^{\circ}C$ latitude would be warm monomictic. From the examination of simulated current velocity distribution, it was found that the upstream inflows would infiltrate into mesolimnion of the lake during hydrodynamic summer monsoon periods due to the thermal density of water.