• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.124-124
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• 2022

가뭄시 유역 수문량은 하천수/지하수 취·배수, 하·폐수방류량, 용수재이용 등 복잡한 물이용체계에 따른 영향이 크지만 기존 가뭄시 수문량 평가는 이러한 복잡한 물이용체계를 고려하지 않아 정도 높은 예측에 어려움이 있다. 따라서 가뭄시 유력 내 상세물이용체계 및 수문환경특성 인자들의 상호작용 규명을 통한 정도 높은 수문량 평가 기술의 개발이 시급하다. 대하천 주변 광역상수도 공급지역은 가뭄 발생시에도 안정적으로 물이용이 가능하나, 중소하천을 수원으로 하는 하천의 상류지역은 가뭄시 물공급 안정성이 취약하다. 따라서 중소하천을 대상으로 가뭄시 물 공급시설의 효율적 운영, 물부족 위험도 평가, 가용수자원의 최적이용 등 종합적인 대책 마련을 위해서는 신뢰성 높은 수문량(하천유출량 및 수자원가용량) 예측이 필요하다. 가뭄에 따른 중소하천유역의 수문학적 유출거동을 평가하기 위한 해석 모형으로는 국내의 복잡한 유역 수문환경특성을 평가하기 위해 개발된CAT (Catchment hydrologic cycle Assessment Tool)(김현준 등, 2012)을 이용하였다. CAT은 기후변화나 토지이용변화에 따른 유역의 수문환경특성 변동성을 정량적으로 평가하기 위해 개발된 모형이다. CAT은 인위적인 물이용체계 즉, 광역급수, 용수재이용, 지하수 취수, 하천수 취·배수 등을 분석하기 위한 툴을 제공하므로 가뭄시 상세물이용체계에 따른 시·공간적 수문환경특성 분석 및 수문량 평가를 위한 최적의 모형으로 선정하였다. 본 연구에서는 중소하천유역의 수문량 예측기술 실용화 기반을 마련하기 위하여 낙동강, 금강, 영산/섬진강 중권역을 대상으로 정밀 시공간 수문량을 평가하였다. 각 권역별 보정지점을 기준으로 관측유량 자료와 모의자료의 1:1비교를 통해 수문량 예측정확도를 산정하였으며, 모형효율(Nash Sutcliffe Efficiency, NSE) 및 결정계수(Coefficient of Determination, R²)의 권역별 평균은 NSE 72%, R2 79%로 나타났으며, 대부분의 지점에서 70% 이상을 나타내어 환경부 및 지자체의 가뭄시 물관리 정책을 지원하기 위한 실용화 기반을 마련하였다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.23 no.2
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• pp.50-68
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• 2024

This study developed a bus route sketch (BRS) methodology for utilizing bus route design and operation steps in practice and evaluated the feasibility of the method. The BRS methodology consists of three steps: transportation zoning suitable for the provider and users of bus transit service; determining the bus operation route based on established transportation zones and path combination; optimizing the operation route based on the estimation of route alternatives in terms of the multi-performance measures from the standpoints of bus-transit service provider and user. The results of a case study showed that the estimation scores from the perspectives of provider and user were improved significantly from 8.83 and 7.13 to 9.50 and 9.89, respectively. Because the BRS method was designated and developed to be suitable for field application for route planning and operation, the method can be used instantly and directly to estimate and adjust the on-operation bus transit line and route design.

• Korean Journal of Agricultural Science
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• v.36 no.1
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• pp.99-109
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• 2009

This study was performed to evaluate the effect of increasing instream flow at Nonsancheon stream of Nonsan city by securing water storages in upstream reservoirs; Ge-ryong, Gyoung-cheon, Dae-dun, and Tab-jeong. The paralleled and cascaded upstream reservoir operations for 8 storage securing scenarios were considered to simulate daily streamflows at Nonsan station. Using Tab-jeong reservoir water storage, the DAWAST model's parameters were determined, and the verified result showed Nash-Schcliffe's coefficient of 0.666. Instream flows were analyzed to supply maximum $59.85Mm^3$ on an annually average from upstream reservoir storage securing scenarios. The storage securing set of 2 m heightened Ge-ryong, 5 m Dae-dun, and 1 m Tab-jeong showed that the additional secured water storages were $17.132Mm^3$ and instream flow at Nonsan station was increased to $2.183m^3/s$, 2 times of present condition.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3304-3310
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• 2010

This study solves the decision making problems for TFT-LCD manufacturing supply chain with demand and price uncertainties by establishing robust production and distribution strategies. In order to control the decisions regarding production graded by quality, inventory level and distribution, this study develop scenario model based stochastic mixed integer linear programs (SMILPs) that consider demand and price uncertainties as well as realistic constraints such as capacities etc. The performance of the solution obtained from the SMILPs using robust algorithms will be evaluated through various scenarios.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.5C
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• pp.512-521
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• 2002

Recently, conventional superscalar RISC processors arrive their performance limit, and many researches on the next-generation architecture are concentrated on SMT(Simultaneous Multi-Threading). In SMT processors, multiple threads are executed simultaneously and share hardware resources dynamically. In this case, it is more important to supply instructions from multiple threads to processor core efficiently than ever. Because SMT architecture shows higher IPC(Instructions per cycle) than superscalar architecture, performance is influenced by fetch bandwidth and the size of fetch queue. Moreover, to use TLP(Thread Level Parallelism) efficiently, fetch thread selection algorithm and fetch bandwidth for each selected threads must be carefully designed. Thus, in this paper, the performance values influenced by these factors are analyzed. Based on the results, an optimal instruction fetch strategy for SMT processors is proposed.

• The Journal of the Korea institute of electronic communication sciences
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• v.3 no.4
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• pp.276-281
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• 2008

Because the distribution systems experience frequently the fault by several causes, the identification task of fault location plays very important role in the view point of power supply reliability. The distribution systems are designed as radial structure with three-phase and single-phase branch line to supply the electric power to the widely dispersed loads, and it have a several load taps within each line segment. it makes the accurate fault distance determination difficult. Accordingly in this papers, the existing fault point determination methods are surveyed and analyzed, and then a fault distance determination method for distribution feeder is adopted which can be executed effectively in DAS center. Finally, the adopted method is verified using EMTP simulation.

• Journal of Korea Society of Industrial Information Systems
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• v.5 no.3
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• pp.10-17
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• 2000

This paper focuses m the measurement of increased work efficiency and competitive advantage expected from the implementation of information systems through random interactions of the organizational behavioral factors whose attributes can be changed with. Specifically, the work reported here is concerned with modeling and analyzing the interrelationships among the organizational behavioral factors which a university information system can have impact on throughout the time horizon of its implementation in terms of productivity. In addition, it is also concerned with developing a continuous simulation model to be used to assess the impact of the information system.

• Proceedings of the Korean Society of Computer Information Conference
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• 2021.01a
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• pp.201-204
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• 2021

본 연구에서는 휴대 할 수 있는 선형 LED 전광봉으로 2차원 LED 전광판 효과의 구현을 시도하였다. 전광봉을 회전하면 전광판의 효과가 나도록 구성한 것으로, adafruit의 스트립(strip) 형 네오픽셀(NeoPixel) 1 × 16 LED으로 형성되는 구조물을 만들고, 이를 제어 할 수 있는 회로와 제어 프로그램을 설계하고 구현하였다. 구현한 전광봉은 큰 전력 소모에도 문제없도록 리튬 이온 충전지를 이용하여 전원이 공급되도록 하여 휴대성을 구현하였고, 블루투스 칩이 부착된 아두이노를 이용하여 하드웨어 구성을 완료하였다. 아두이노에는 C++를 이용하여 전광봉으로 전광판 효과를 볼 수 있도록 LED들을 통제하는 제어용 프로그램을 구성하였을 뿐 아니라 블루투스를 이용한 스마트 폰과 통신할 수 있는 프로그램을 구현하였다. 대략 6도 단위로 LED가 제어 되도록 하여 1회전에 16 × 60 정도의 전광판 효과를 볼 수 있다. 스마트 폰에는 원하는 전광판을 구성할 수 있도록 색상 팔레트 형성 기능과, 통제용 전광판의 크기를 결정 기능, 크기가 결정된 전광판에서 원하는 색으로 홍보용 내용이 불이 켜질 수 있도록 전광판 구성 기능, 구성된 전광판 자료를 CSV(Comma Separate Value) 파일로 저장하고, 전광봉으로 보낼 수 있는 기능을 구성하였다.

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.5
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• pp.360-370
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• 2009

Using solar power in wireless sensor networks requires a different approach to energy optimization from networks with battery-based nodes. Solar energy is an inexhaustible supply which can potentially allow a system to run forever, but there are several issues to be considered such as the uncertainty of energy supply and the constraint of rechargeable battery capacity. In this paper, we present SolarSS: a reliable storage system for solar-powered sensor networks, which provides a set of functions, in separate layers, such as sensory data collection, replication to prevent failure-induced data loss, and storage balancing to prevent depletion-induced data loss. SolarSS adapts the level of layers activated dynamically depending on solar energy availability, and provides an efficient resource allocation and data distribution scheme to minimize data loss.

• Journal of Korea Port Economic Association
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• v.35 no.3
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• pp.125-150
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• 2019

The Hunchun area is the only development and opening line in Jilin Province and the Changchun-Jilin-Tumen Developmental Plan area, and as a hub area for regional logistics, promoting the logistics competitiveness of the Hunchun area is an important factor in promoting economic development in the Northeast region. The purpose of this study is to derive the factors for activating logistics competitiveness in Hunchun area by applying SWOT analysis and to present them to policy-makers by drawing priority of factors for promoting logistics competitiveness in Hunchun area through AHP survey of Chinese and Korean logistics experts. According to the analysis, the weighting was high in order of opportunity factors and strength factors, and the priority was high in order of factors such as promotion and expansion of One Belt, One Road policies, active support through national policies, construction of international logistics center cities, construction of logistics centers, and supply of bulk cargo. Finally, from a comprehensive perspective, this study presented policy implications such as SO Strategy (Strength-Occupancy Strategy) and ST Strategy (Strength-War Strategy) focusing on the strengths of the Hunchun Region for the strategy of strengthening the logistics competitiveness of the Hunchun area.