• 항공우주기술
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• 제2권1호
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• pp.140-152
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• 2003

발사를 위해 로켓과 지상 장비를 작동시키고 제어하는 과정에서 시나리오는 운영 및 통제의 지침 역할을 한다. 따라서 시나리오를 작성하는 것은 로켓 발사 작업을 준비하는 첫 번째 작업으로서, 발사를 성공적으로 수행하기 위한 핵심적인 임무 중 하나이다. KSR-III 비행시험 시나리오는 발사를 준비하기 위해 로켓과 지상 장비를 작동시키는 순차적인 작업 명령의 시퀀스이다. 본 논문에서는 발사 시나리오 개발에 UML 객체 모델링 방법을 적용한다. 먼저, 발사 시스템의 각 서브시스템을 객체로 모델링하고 각 두 서브시스템 간의 인터페이스를 association link로 모델링한다. 이를 통해 얻어진 최종적인 KSR-III 발사 시스템 객체 다이어그램은 데이터와 명령의 흐름, 통제, 상호작용 등을 분석하는데 사용된다. 전체 시나리오는 사전 시나리오, 본 시나리오, 비상시 조치사항 등으로 구성된다.

• 한국물환경학회지
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• 제35권6호
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• pp.470-480
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• 2019

The Doam lake watershed was designated as a non-point pollution management area in 2007 to improve water quality based on watershed management implementation. There have been studies of non-point source reduction with respect to the watershed management impacting the pollutant transport of the reservoir. However, a little attention has been focused on the impact of water quality improvement by the management of the dam operation or the guidelines on the dam operation. In this study, the impact of in-lake management practices combined with watershed management is analyzed, and the appropriate guidelines on the operation of the dam are suggested. The integrated modeling system by coupling with the watershed model (HSPF) and reservoir water quality model (CE-QUAL-W2) was applied for analyzing the impact of water quality management practices. A scenario implemented with sedimentation basin and suspended matter barrier showed decrease in SS concentration up to 4.6%. The SS concentration increased in the scenarios adjusting withdrawal location from EL.673 m to the upper direction(EL.683 m and EL.688 m). The water quality was comparably high when the scenario implemented all in-lake practices with water intake at EL.673 m. However, there was improvement in water quality when the height of the water intake was moved to EL.688 m during the summer by preventing sediments inflow after the rainfall. Therefore, to manage water quality of the Doam lake, it is essential to control the water quality by modulating the height of water intake through consistent turbidity monitoring during rainfall.

• 대한조선학회논문집
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• 제59권5호
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• pp.252-261
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• 2022

The present study concerns assessing the operability of a surface combatant, based on the Percent-Time-Operable (PTO). For validation of the seakeeping analysis in the regular waves, the model test is first conducted in a towing tank. The seakeeping analysis results in the regular waves are expanded to the irregular waves, considering the wave spectra around the Korean peninsula and in North Pacific. The seakeeping criteria of the surface combatant in transit, combat, replenishment operation, and survival condition are defined by the literature review. An annual operation scenario of the surface combatant in two operation areas, i.e., advance speed and wave direction, are combined with the seakeeping analysis results to assess PTO. The main constraints of operability of the surface combatant are identified as the pitch angle and vertical velocity at the helicopter deck.

• 한국가스학회지
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• 제21권1호
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• pp.34-42
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• 2017

도시가스 정압기 안전 운영을 위한 운전원 안전훈련시스템의 주요 구성 요소 중 하나인 안전훈련 시나리오를 설계하고 구현함에 있어서, 단일 시나리오가 일방적으로 진행되는 기존 훈련 방식을 개선한 훈련 방안을 연구하였다. 안전훈련시스템과 운전원간의 상호 작용을 통해 훈련 시나리오의 다양성을 향상시켜 훈련 효과를 올리는 방안으로 플랜트 안전훈련 플랫폼 상에서 적용 가능한 Finite State Machine 모델 기반의 인터랙티브 훈련 방안을 개발하였다. 본 훈련 시나리오 시스템으로 인해 향후 확장된 대상 플랜트에의 안전훈련시스템 적용 가능성을 기대해볼 수 있었다.

• 항공우주시스템공학회지
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• 제16권5호
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• pp.49-56
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• 2022

S-STEP 은 관심 지역의 시한성 긴급 표적 및 군사적 이상 징후를 감시하기 위한 초소형 SAR 위성 임무로, 고도 510 km의 저궤도에 32 대의 위성군을 배치하여 관심 지역에 대해 평균 재방문 주기를 30 분 이하로 달성한다. S-STEP의 임무 운용 모드는 표준 모드, 관측 모드, 통신 모드, 궤도유지 모드 등으로 구분되며, 이에 따라 자세 기동 모드 역시 초기 각속도 안정화, 태양 지향, 목표지점 및 지상국 지향, 추력 방향 유지 등으로 세분화된다. 이 연구에서는 S-STEP 임무 운용 시나리오의 예비 설계 결과와 위성체의 특성을 바탕으로 초기 각속도 안정화 및 태양 지향 모드와 관측 궤도 운용 모드에서의 자세 성능을 분석하였다. 분석 결과, 할당된 시간 이내에 필요한 자세 제어를 완료하여 각 모드에서 요구되는 자세 제어 정확도를 달성함을 확인하였다.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2002년도 학술대회 논문집
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• pp.56-59
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• 2002

Since the KSTAR magnet structure should be maintained at cryogenic temperature of about 4.5 K, even a small amount of heat might be a major cause of the temperature rising of the superconducting magnet structure. The Joule heating by eddy current induced on the magnet structure during the KSTAR operation was found to be a critical parameter for designing the cooling scheme of the magnet structure as well as defining the requirements of the refrigerator for the cryogenic system. Based on the Joule heating calculation, it was revealed that the bulk temperature rising of the magnet coil structure was less than 1 K. The local maximum temperature especially at the inboard leg of the TF coil structure increase as high as about 21 K for the plasma vertical disruption scenario. For the CS coil structure maximum temperature of 8.4 K was obtained from PF fast discharging scenario.

• 한국전자통신학회논문지
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• 제11권8호
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• pp.729-734
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• 2016

현재 국내 철도 무선통신망은 구간별로 VHF, TRS-ASTRO, TRS-TETRA 등의 서로 상이한 통신방식을 사용하여 정보를 송수신하고 있다. 최근에는 다양한 서비스를 제공하고 신뢰성을 향상시키기 위해 LTE방식을 철도 무선통신에 적용하는 연구가 진행 중에 있다. 다양한 통신방식을 사용하는 철도 무선통신망에서 끊김 없는 정보전송을 제공하기 위해서는 기존 통신방식과 새로운 통신방식 간의 연동이 필수적이다. 본 논문에서는 두 가지 망 연동방안, 즉 단말기 중심의 연동방안 및 망 중심의 연동방안에 대해 소개한다. 두 가지 연동방안을 이용한 운용시나리오에 대해 알아보고 두 가지 방안의 차이점을 비교한다. 또한 실제 시스템 적용시 고려사항에 대해서도 논의한다.

• 상하수도학회지
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• 제31권5호
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• pp.409-414
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• 2017

In this study, we divided the process operation scenarios into three categories based on raw water temperature and turbidity. We will select and operate the process operation scenario according to the characteristics of the raw water. The number of algae in the DAF treated water has been analyzed to be less than 100 cells/mL. These results indicated that the DAF process is effective in removing the algae. In addition, the scenario of the integrated management decision algorithm of the DAF process was developed. DAF pilot plants ($500m^3/day$) process has shown a constantly sound performance for the treatment of raw water, yielding a significantly low level of turbidity (DAF treated water, 0.21~1.56 NTU).

• 한국국방경영분석학회지
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• 제28권1호
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• pp.29-46
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• 2002

This study focuses primarily on the construction of the wartime sealift operation model from US to Korea. There are some uncertainties in the process of sealift operation such as the procurement rate of materiel in US, the distribution of KFS on four initial position locations at the start of the activation, and the number of ports and berths in the SPOES and SPODS. The sealift capability, based on the allocation of sealift assets such as the number of vessels, berths, and ports, is evaluated through simulation. The simulation is executed with a baseline wartime scenario and then the results are analyzed through a sensitivity analysis. The military planner may use of this model as a standard for establishing effective and concrete sealift operation plan in the near future.

• 한국환경복원기술학회지
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• 제22권5호
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• pp.27-43
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• 2019

This study applied the LANDIS-II model to the forest vegetation of the study area in Yeongdong-gun, Korea to identify climate effects on ecosystems of forest vegetation. The main purpose of the study is to examine the long-term changes in forest aboveground biomass(AGB) under three different climate change scenarios; The baseline climate scenario is to maintain the current climate condition; the RCP 4.5 scenario is a stabilization scenario to employ of technologies and strategies for reducing greenhouse gas emissions; the RCP 8.5 scenario is increasing greenhouse gas emissions over time representative with 936ppm of $CO_2$ concentration by 2100. The vegetation survey and tree-ring analysis were conducted to work out the initial vegetation maps and data for operation of the LANDIS model. Six types of forest vegetation communities were found including Quercus mongolica - Pinus densiflora community, Quercus mongolica community, Pinus densiflora community, Quercus variabilis-Quercus acutissima community, Larix leptolepis afforestation and Pinus koraiensis afforestation. As for changes in total AGB under three climate change scenarios, it was found that RCP 4.5 scenario featured the highest rate of increase in AGB whereas RCP 8.5 scenario yielded the lowest rate of increase. These results suggest that moderately elevated temperatures and $CO_2$ concentrations helped the biomass flourish as photosynthesis and water use efficiency increased, but huge increase in temperature ($above+4.0^{\circ}C$) has resulted in the increased respiration with increasing temperature. Consequently, Species productivity(Biomass) of trees decrease as the temperature is elevated drastically. It has been confirmed that the dominant species in all scenarios was Quercus mongolica. Like the trends shown in the changes of total AGB, it revealed the biggest increase in the AGB of Quercus mongolica under the RCP 4.5 scenario. AGB of Quercus mongolica and Quercus variabilis decreased in the RCP 4.5 and RCP 8.5 scenarios after 2050 but have much higher growth rates of the AGB starting from 2050 under the baseline scenario. Under all scenarios, the AGB of coniferous species was eventually perished in 2100. In particular they were extinguished in early stages of the RCP 4.5 and RCP 8.5 scenarios. This is because of natural selection of communities by successions and the failure to adapt to climate change. The results of the study could be expected to be effectively utilized to predict changes of the forest ecosystems due to climate change and to be used as basic data for establishing strategies for adaptation climate changes and the management plans for forest vegetation restoration in ecological restoration fields.