• Journal of the Korea Society of Computer and Information
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• v.13 no.7
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• pp.239-246
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• 2008

The supplier selection has a direct effect on the organization's efficiency, effectiveness and competitiveness, so the right supplier selection is the most important decision of a company. In order to select the best suppliers, both qualitative and quantitative factors should be considered. To decide which suppliers are the best and how much should be purchased from each selected supplier, many models which considered a single objective and multiple objectives have been proposed. But they have problems in considering qualitative factors which are very important in supplier selection. So in this article an integration model of an analytical hierarchy process and linear programming is proposed to consider both qualitative and quantitative factors in choosing the best suppliers and placing the optimum order quantities among them. This integrated model can be applied effectively and easily any organization and management circumstances.

• Korea Trade Review
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• v.43 no.3
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• pp.147-168
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• 2018

Korean foreign direct investment (FDI) firms procure cheap raw materials, produce goods in developing countries featuring low rent and labor costs, and sell goods in world market. In this regard, global supply chain management is important to Korean FDI firms. The objective of this study is to analyze gaps in the performance of reliability and quality of supply chain orientations. To achieve this objective, this study confirms theoretical relationships between variables through prior research, selects measuring variables, and analyzes data collected from Korean FDI firms. Results are as follows; First, there is a gap in reliability performance among the levels of supply chain orientation. Managers should check the level of their supply chain orientation and make strategic and structural efforts to improve reliability performance. Second, there is a gap in quality performance among the levels of supply chain orientation. To improve quality performance, managers should identify the level of their supply chain orientation. In addition, managers can enhance quality performance on the basis of strategic and structural efforts.

• Journal of Digital Convergence
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• v.11 no.7
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• pp.83-95
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• 2013

Supply chain management for engineering project focuses on planning acquisitions, identifying and choosing the right suppliers and subcontractors, planning and negotiating appropriate contracts, and administering the collaboration with the suppliers and subcontractors. This paper aims to identify the determinants of SCM performance of the suppliers and subcontractors participating in the project-based supply chain. This study proposes the absorptive capacity, fairness of suppliers' evaluation, the quality of collaboration and incentives as major research variables, and collected the survey responses from the suppliers and subcontractors having experiences with major engineering projects. The statistical results indicate that the incentives, absorptive capacity and the quality of collaboration influence SCM performance of suppliers, and that the fairness of suppliers' evaluation has some impact on the incentives and the absorptive capacity. But on the contrary to our expectation, the incentives have no significant impact on the level of absorptive capacity.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.65-65
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• 2020

기후변화에 관한 IPCC 제5차 평가보고서에 따르면 최근 나타난 기후 관련 극한 현상인 폭염, 홍수, 가뭄 등의 영향에 대해 생태계가 현재의 기후 변동성에 상당히 취약하게 반응하며, 기후변화를 위험에 초점을 맞추어 평가함으로써 대응책을 마련해야 한다고 강조하였다. 기후변화에 따라 강수량 패턴과 수문학적 시스템이 변하면서 수자원의 미치는 영향과 취약성, 적응에 대한 연구의 필요성이 요구되고 있으며, 농업용수를 비롯한 수자원 관리 기술 및 적응역량을 강화하는 것이 필요하다. 수리답 면적에 대한 농업용수 공급의 61%를 차지하는 농업용 저수지의 경우 과거 10년 한발빈도로 설계되어 최근의 연속적인 가뭄 사상으로 인한 낮은 저수율을 나타내어 가용 수자원의 부족이 발생하였다. 이에 따라 저수지 설계 당시와 상이한 환경 및 기후의 변화로 농업용수 공급체계의 상황변화에 따른 용수공급능력 및 이수안전도의 재평가가 요구된다. 일부 가뭄대책지구에 대하여 기후변화에 따른 현장여건 변화 (논면적, 영농패턴, 작부시기 등)를 반영한 이수안전도를 재평가함으로써 농업용 저수지의 용수공급에 대한 정량적 분석이 수행되었다. 저수지별로 기후변화 및 현장여건 변화에 따른 영향이 다르므로 전국 농업용 저수지를 대상으로 확대, 적용하기 위해서는 저수지 특성을 분석하여 비슷한 패턴을 갖는 저수지로 유형화하기 위한 작업이 필요하다. 본 연구에서는 농어촌공사 관할 3,394개의 농업용 저수지를 대상으로 지역에 따라 인자별 군집분석을 실시하여 국내 농업용 저수지의 이수안전도 변화에 따른 물 공급 잠재능을 재평가하고자 한다. 본 연구의 결과는 기후와 영농방식, 지역별 특성 등 상호간의 관계를 고려한 농업용수관리와 유사한 특성을 갖는 지역계획의 추진단위를 결정하거나 지역간의 비교우위를 고려한 한해 대책 등과 같은 농촌지역개발계획 등에 활용할 수 있을 것으로 기대한다.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.470-478
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• 2016

Greenhouse gas (GHG) emissions caused by fossil fuels consumption is one of the challenging issues worldwide. Renewable energy source (RES)-based energy supply system can be a promising alternative to the current fossil fuel-based system. In this study, we propose an optimization approach for designing a stand-alone hybrid energy supply system using RES and evaluating economic performances of the energy systems. The suggested approach is used to answer the questions; i) what technology is suitable to various demand sectors in different regions, and ii) how does it cost to meet the demand in term of the levelized costs of energy (LCOE). We illustrate the applicability of the proposed approach by applying to the design problem of energy supply systems for residential, agricultural and commercial sectors of Korea. As the results of LCOE analysis, for the residential sector has the LCOE ranging of $0.37~$0.44/kWh, the agricultural sector of $0.15~$0.61/kWh and the commercial sector of $0.12~$0.28/kWh.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.437-437
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• 2021

새만금유역의 용수이용체계는 농업용수를 중심으로 이루어져 있고, 대규모 관개시스템을 통해 하천수가 농업용수로 공급되고 있어 하천의 수질관리와 수생태계 보전에 어려움을 겪고 있다. 특히, 농업용수와 공업용수 대부분을 하천으로부터 확보하고 있는 만경강은 용담댐과 금강호와 같은 외부 공급원에 의존하고 있으며, 유역내 위치하고 있는 수원인 대아저수지와 경천저수지는 관개기에 대부분 유량을 농업용수로 공급하고 있어 하천유지유량 유지에 어려움을 겪고 있다. 본 연구는 만경강유역의 용수별 공급 및 이용체계에 따른 용수 확보방안을 검토하고 수질에 미치는 영향을 평가하고자 한다. 이를 위해 유역내에서 용수 확보방안에 따른 시나리오를 구성하였고, 수역의 기작 등을 합리적으로 구현할 수 있는 수질예측 모델을 구축하여 본류구간의 수질변화를 예측하였다. 수질모의시 유황조건은 하천수질환경기준의 설정근거인 저수량(Q₂₇₅)과 평수량(Q₁₈₅)을 기준으로 하였고, 각 구간별 수리입력계수와 수질입력계수를 입력하여 보정하였으며, 보정 및 검증자료는 환경부 자료에서 기준유량의 ±20 % 내에 측정된 시기의 값을 활용하였다. 수치해석 결과, 저수량 조건에서 시나리오별 확보되는 유량증가에 의해 주요지점에서의 수질개선율이 평균 BOD 12.1 %, T-N 4.9 %, T-P 10.1 %, 평수량 조건에서 평균 BOD 4.7 %, T-N 4.1 %, T-P 5.6 %로 평가되어 본류구간의 유량이 증가할수록 수질이 개선되는 것으로 나타났다. 따라서 유역내 용수별 공급 및 이용체계에 따라 확보되는 유량을 효율적으로 이용한다면, 외부 수자원에 의존하지 않고 유역내에서 자체적으로 만경강 및 새만금호의 유입량을 확보뿐만 아니라 수질개선에도 기여할 것으로 판단된다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.5
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• pp.477-484
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• 2020

Reservoir operation affects the sustainability of a water supply. However, the increase in the temporal and spatial variability of rainfall, attributed to climate change, has led to severe droughts and increased difficulty in maintaining a sustainable discharge at certain locations in a reservoir system operation. In this study, water yield was evaluated using reservoir simulation with varied water supply. Three reservoir system models were simulated for nine reservoirs in the Han River basin. The time-based reliability, volumetric reliability, and resiliency were used to evaluate the results. Each case was simulated by applying firm supply, deficit supply, and deficit supply with historical power release of the Hwacheon Reservoir. As a result of the simulation, all indexes were increased when the deficit supply was applied. In particular, the time-based reliability increased by more than 30%, and the supply reliability increased by about 4%. The result showed that the water supply of the entire water system could be increased when all reservoirs in the water system were operated to supply water and maintain sustainable discharge at the same downstream point. The deficit supply was an efficient reservoir operation method for responding to climate change, especially increased rainfall variability.

• The Journal of the Korea Contents Association
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• v.9 no.8
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• pp.99-112
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• 2009

The research is to develop U-IT Technology Transfer Re-auction System Model for technology transfer enable transactions of buyer-oriented. The buyer sends condition technology parts and data informations to provider. The First step, The buyer sends condition technology parts and data informations to provider. The Second step, the buyer's technology and conditions in the First step will be transferred to the DB of a provider who can provide that technology. The Third step, a provider can bid after inputting the conditions. The Fourth step, the buyer decides the ranking of successful bids in condition-optimized auction process. The Fifth step, the buyer invites a provider to be a successful bidder. The last step, if there's no successful bid within the period, the sale considered failed. The buyer-oriented re-auction system is that the deal will become extinct automatically when its sale failed more than two times.

• Journal of Korea Water Resources Association
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• v.45 no.4
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• pp.361-371
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• 2012

For a basin with existing reservoirs, the necessity of additional water demands has been proposed, as well as a reevaluation of existing reservoir yield has been proposed. The objective of this study is to reevaluate a multipurpose reservoir yield and to assess the possibility of additional water supply according to increase of downstream water demands. Andong and Imha Reservoirs are selected for reevaluation. The standard reservoir operation rule model and the HEC-ResSim model were used for reservoir simulation for 30 years (1979~2008). In this study, water supply reliability was set up as 96.7% and 95.0% with yearly and monthly evaluating unit. In case of 95% water supply reliability with yearly evaluating unit, water supply capability of Andong reservoir was evaluated as 893MCM and water supply capability of Imha reservoir was evaluated as 382MCM, and that results showed that water yields for both reservoirs are less than the original designed yields.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.232-241
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• 2017

This paper presents an automated cow-feeding system based on an AGV and screw conveyor for domestic livestock farms, which are becoming larger and more commercialized. The system includes a hopper module for loading pellet-type mixed feed at the top of the system, a transfer module mounted with a screw conveyor to transfer feed from the hopper module to the outlet module, an outlet module composed of belt conveyors, and an electromagnetic guided driving-type AGV. The weight of the loaded feed is measured by a load cell located under the transfer module. The system reads the feed discharge information stored in RFID tags installed in each cowshed cell, and a predetermined amount of feed is discharged while the AGV is moving. A cow-feed test system was constructed to determine the design parameters of the screw conveyor in the transfer module that determine the feeding capacity. These parameters include the screw's outer diameter, the screw shaft outer diameter, and screw pitch. The parameters were applied to the finalized cow-feed system construction. A DSP-based main controller and cow-feeding algorithm for different scenarios were also developed to control the system. Experimental results confirmed that the system could supply a total of 21 kg of feed uniformly at 420 g/s for a cowshed cell which has 7 cows. The driving distance was 5 m and the speed was 0.1 m/s. Thus, the proposed system could be applied to standardized domestic livestock farms.