• 한국유체기계학회 논문집
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• 제15권6호
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• pp.18-24
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• 2012

This study simulated the operation of a steam injected gas turbine combined heat and power (CHP) system. A full off-design analysis was carried out to examine the change in the turbine blade temperature caused by steam injection. The prediction of turbine blade temperature was performed for the operating modes suggested in the previous study where the limitation of compressor surge margin reduction was analyzed in the steam injected gas turbine. It was found that both the fully injected and partially injected operations suggested in the previous study would cause the blade temperature to exceed that of the pure CHP operation and the under-firing operation would provide too low blade temperature. An optimal operation was proposed where both the turbine inlet temperature and the injection amount were modulated to keep both the reference turbine blade temperature and the minimum compressor surge margin. The modulation was intended to maintain a stable compressor operation and turbine life. It was shown that the optimal operation would provide a larger power output than the under-firing operation and a higher efficiency than the original partially injected operation.

• 한국군사과학기술학회지
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• 제13권6호
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• pp.1099-1105
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• 2010

The purpose of this paper is to propose a methodology that can estimate optimal requirement of attack helicopter Korea army will be operating in future. For estimating optimal requirement, attack helicopter's operation concept, performance, battlefield environment and enemy threat are considered. We use a wargame model, AAsim(Army Aviation simulation), as a analytic simulation model which is used to analyze DOTMLPF and operation in army aviation field. In this paper, we conduct battle experiment for anti armored corps operation which reflects attack helicopter's combat effectiveness very well. As a result of simulation, the destructive rate for enemy armored corps per each attack helicopter can be calculated. In this paper, we propose optimal requirement of attack helicopter using that destructive rate for enemy armored corps.

• Korean Chemical Engineering Research
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• 제46권1호
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• pp.147-155
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• 2008

대부분의 화학공장에서는 유틸리티의 운용에 따라 경제성이 크게 좌우된다. 공장에서 이용되는 유틸리티는 중앙 집중화된 유틸리티 시스템에 의해 제공되는데 유틸리티 가운데 가장 큰 비중을 차지하는 것은 수증기로서 이의 효율적인 관리는 공장의 전력 및 용수의 수급에도 직접적인 영향을 미치게 된다. 이에 따라 대학교 4학년 학생 및 회사의 신입사원들이 유틸리티의 효율적 분배에 대한 개념을 바르고 신속하게 정립하고 실제 운전에 활용할 수 있도록 하는 것이 중요하다. OOUS(optimal operation of utility system)는 빠른 시간 내에 유틸리티, 특히 수증기의 효율적 생산과 최적 배분방법들을 학생들이나 신입사원들에게 교육시킬 수 있도록 구성된 시스템이다. OOUS에서는 다양한 유틸리티 관련장치 및 공정들을 다루고 있으며 유틸리티 관련 장치 모델과 운전지식 베이스를 기반으로 최적 운전조건이 제시되도록 함으로써 전체 유틸리티 플랜트의 조업 경비가 절감될 수 있도록 하였다.

• 전기학회논문지
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• 제60권8호
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• pp.1467-1472
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• 2011

This paper presents an optimal operation of microgrid systems and considering a tie-lines capacities that concerned each grid. The microgrid system consists of a wind turbine, a diesel generator, and a fuel cell. An one day load profile and wind resource for wind turbine generator were used for the study. For the grid interconnection, tie-line capacities were applied as constraints. The capacity constraints of tie-lines in production cost analysis are very important issues in the operation and planning of microgrid. In optimization, the Harmony Search (HS) algorithm is used for solving the problem of microgrid system operation which a various generation resources are available to meet the customer load demand with minimum operating cost. The application of HS algorithm to optimal operation of microgrid proves its effectiveness to determine optimally the generating resources without any differences of load mismatch.

• 한국지열·수열에너지학회논문집
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• 제14권1호
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• pp.16-21
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• 2018

This work aims to develop a platform to investigate the effect of operation schedules on the building energy consumption and to derive a simulation model based optimal start and stop daily strategy. An open-source building energy simulation tool DOE2 is used for the engine, and the developed simulation model is validated using ASHRAE guideline 14. The effect of late-start/early-stop operation of HVAC system on the daily building energy consumption was analyzed using the developed simulation model. It was found that about 10% of energy consumption cut was possible using the control strategy for an hour of advance of the stop operation, and about 3% per an hour of delay of the start operation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.360-362
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• 2003

In operation of distribution system, DGs(Distributed Generations) are installed as an alternative of extension and establishment of substations, transmission and distribution lines according to increasing power demand. Optimal capacity and allocation of DGs improve power quality and reliability. This paper proposes a method for determining the optimal number, size and allocation of DGs needed to minimize operation cost of distribution system. Capacity of DGs for economic operation of distribution system can be estimated by the load growth and line capacity during operation planning duration. DG allocations are determined to minimize total cost with failure rate and annual reliability cost of each load point using GA(Genetic Algorithm).

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.431-436
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• 2002

Train driving should be satisfied to run fixed distance within given time, and it is desirable to minimize energy consumption. Minimizing energy consumption depends on the train operation modes by driver or automatic operation. In this article, an optimal operation to minimize energy consumption by changing modes of train operation by a driver is investigated. First, powering model, braking model and consumed energy calculation model are introduced by using Matlab software. The accuracy of the model established by simulation is compared with the real experimental data, which is obtained from an authorized institution. Second, several simulations under a variety of operations in the ideal track are executed, and then the optimal pattern of train driving is found.

• 전력전자학회논문지
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• 제14권5호
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• pp.365-371
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• 2009

국내에서는 풍력 발전 기술 집약에 전력하고 있지만 풍력 발전 단지에 대한 운영 경험은 매우 제한적이며, 연계 기준 수립에 대한 기초가 부족한 실정이다. 따라서 국내 계통의 특성을 고려한 연계 기준 및 최적 운영 방안 수립을 위하여 여러 국가에서 적용하고 있는 풍력 발전 단지의 연계기준 및 최적 운영 방안에 대한 검토가 필요하다. 이에 본 논문은 제주계통을 대상으로 한 모의를 통하여 대규모 풍력 발전 단지의 최적 운영 방안에 대한 필요성을 확인하고 제안한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 A
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• pp.102-105
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• 1993

The objective of this study is to solve the operation scheduling problem of plural battery energy storage systems (BESS), and to find useful intonation from its result. Unlike conventional energy storage system, BESS has on hardware characteristics such as high efficiency, fast-acting response and operational loss. Considering rate constraints of thermal unit power as well as hardware characteristics of BESS, the operation scheduling has an intricated problem. In order to solve this optimization problem, we use successive approximations dynamic programming. In two types of operation, the proposed algorithm is applied to test system. one is daily optimal operation, the other weekly optimal operation.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
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• pp.105-106
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• 2012

This study is numerical analysis about optimal conditions of GDICI (gasoline direct injection compression ignition) engine operation using intake preheating. Numerical modeling was performed by using the KIVA-3V Release2 code integrated Chemkin chemistry solver II. For validation of numerical model, experiments were performed on a single-cylinder engine. Throughout the numerical simulations under variable conditions, the ranges of optimal conditions were found.