• 한국군사과학기술학회지
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• 제14권5호
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• pp.788-797
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• 2011

This paper analyzes the accuracy on the approach and landing of aircraft to an airport through comparison with airbase Precision Approach Radar and aircraft track data of DGPS equipped in aircraft. The proposed analysis result could be a basis for verifying the possibility that DGPS can be utilized in Airbase precision approach and landing. Position identification capability of widely used commercial DGPS is fairly accurate on latitude and longitude, while there is a slight error for being used in an airbase accurate approach and landing of Category I precision when it comes to altitude. Thus, we tested accuracy by analyzing actual flight track data of high performance aircraft to verify the accuracy of the airbase approach and landing using DGPS. Through the research, we developed instrumentation to compare PAR track data with DGPS track data, which can be used in reducing the number of PAR verification Flight utilizing it as a system measuring PAR accuracy at PAR installation phase.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 추계학술대회 논문집
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• pp.217-218
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• 2012

A load motor used for warship or submarine is with limited volume and weight, also specific environmental tests like impact, vibration, noise, temperature and EMC/EMI have to be satisfied. Induction motors, synchronous motors, BLDC motor and etc, are used depending on the purpose of using military equipment. Induction Motors are used for a number of military equipment more commonly due to the robust structure and simple maintenance. Domestic and foreign warships have a wide range of voltages as the DC voltage sources with battery are mainly used for them. The ${\Delta}-connection$ operation of the induction motor is required to make the maximum power in a low voltage level. But the elements' temperature of the inverter increases due to high input current when it is in the ${\Delta}-connection$ operation. Therefore, the induction motor must be driven with the Y-connection. The lack of voltage needs to be with the field weakening control. This paper suggests the optimum field weakening control algorithm to drive the induction motor with maximum power in a limited thermal and DC voltage condition.

• 한국국방경영분석학회지
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• 제3권1호
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• pp.109-114
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• 1977

There are some factors which cause the profits from the production to be decreased or increased. They are, for example, the rise in efficiency of production facilities resulting from the development of the scientific technique, the changes of purchase price of those, and the drop in efficiency of those owing to there long-term operation. In this connection, an manager can get the highest profit by deciding the proper time of new facilities replacement for those in operation or in being planned, which leads to good management planning of his manufactaring business for a given period or a long time. Main purpose of this is the study of how we decide the optimal time or facilities replacement in order to maximize the total profits for a given period by considering them as continous function as to the time in the case where a machineng is set. The results are following: 1. The definition of profit function is in duced in consideration of the breakdowns caused from continous operation of the machinery. 2. The necessary conditions are obtained for the optimal time of replacement and find out the methods of its solution. 3. Comparing between the 'Short cut' method and method in this paper, we obtained that our method is more realistic.

• 한국국방경영분석학회지
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• 제32권1호
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• pp.36-50
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• 2006

한국군은 전시 상당량의 전략물자를 미국으로부터 항공수송을 통해 도입하고자 한다. 이 연구는 항공수송 모델을 형성하고 전시 동원될 민간 항공기를 포함한 동원자원의 항공수송 능력을 평가하는 것이다. 전략 항공수송계획은 국군수송사령부에 의해 매년 조정 수립되고 있으나 항공수송 과정의 불확실성으로 인해 시뮬레이션을 통해 실현가능성을 평가할 필요가 있다. 불확실한 요인은 미국 공항에서의 전략물자 도착에 대한 불확실성, 적하역 시간, 동원령 발령시 항공기 최초 위치 지점 등이다. 시뮬레이션은 두 개의 시나리오 하에서 실행되었으며 결과에 대한 민감도 분석을 수행하였다. 시뮬레이션 결과, 항공수송 능력에 가장 큰 영향을 미치는 요인들은 미국 공항에서의 물자 도착 불규칙성과 항공기 동원 대수이었다.

• 한국군사과학기술학회지
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• 제21권6호
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• pp.767-775
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• 2018

To develop and check a Radar Processor Unit, checking the function and performance of the requirement is very important factor in developing Radar. General methods for verifying the Radar is simulation test, environment linkage test and field operation test, firstly, in case of requirement analysis phase, verify Radar algorithm and design by using mathematical method based simulation test method, and secondly, in case of unit test and integrated test phase, Test Equipment is set to simulate radar environment in the lab to verify radar function and performance. Lastly, field operation test phase is carried out to confirm the function and performance after it is mounted on the actual equipment. To successfully develop Radar Processor Unit, using the method of field operation test method after sufficient test cases are tested in radar environmental interlocking method in order to save cost and testing period and because of this reason, development of the Radar Processor Unit Test Equipment is becoming very important factor. In this paper, we introduce the concept of test equipment development and important factors in test equipment, which are target simulation, data processing and device interlocking.

• 시스템엔지니어링학술지
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• 제18권2호
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• pp.117-125
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• 2022

In the early 2000s, the rapid decline in the fertility rate resulted in a decrease in military resources to maintain the conscription system. In addition, there has been a further decline in the fertility rate in recent years. So, it is necessary to efficiently utilize military resources to prepare for future problems. The Republic of Korea Navy is planning to reduce the number of crew to operate the newly built warships to prepare for this trend of decreasing in troop resources. However, if the number of crew is reduced without reviewing the appropriate number of crew for the operation of the warship, a bigger problem may be encountered in the future. In order to solve this problem, research is being conducted to examine whether the number of crew aboard a warship is appropriate using simulation. However, it is difficult to create a crew simulation model due to the lack of detailed data related to crew operation. In this study, to solve this problem, a method of generating quantitative data using qualitative survey results was suggested, and the process of creating a crew simulation model was performed using this.

• 문화기술의 융합
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• 제9권3호
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• pp.287-292
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• 2023

미국 항공우주국(NASA)은 저고도의 공중을 새롭게 구축하고자 도시의 단거리 항공 운송 생태계를 새로운 개념의 도심항공모빌리티(Urban Air Mobility, UAM)을 제시하여 현재 UAM이라는 용어가 전 세계적으로 통용되고 있다. 이러한 패러다임은 우리나라 정부에서도 2025년까지 도심항공교통 서비스 상용화를 목표로 추진하고 있는 실정이며 더 나아가 급변하는 미래 작전환경 및 전장 공간의 확장으로 공중기동·수송능력 확보 필요성이 대두되고 있어 우리나라 군 조직에서도 필요성이 제기되는 부분이다. 즉, 본 연구는 미 공군의 'Agility Prime' 프로그램을 소개하여 군사적 필요성과 군사적 운용방안에 대해 제시하고자 출발한 연구이며 연구의 체계는 도심항공 모빌리티 배경 및 개념, 한국형 도심항공 모빌리티 발전 추세, 미 공군의 'Agility Prime' 프로그램 분석 순으로 구성하였으며 본 연구에 이어서 후속연구로 진행되길 기대한다.

• 한국정보시스템학회지:정보시스템연구
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• 제31권3호
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• pp.177-195
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• 2022

Purpose This paper aims to prepare a full operational readiness by establishing an optimal flight plan considering the weather conditions in order to effectively perform the mission and operation of military aircraft. This paper suggests a flight prediction model and rules by analyzing the correlation between flight implementation and cancellation according to weather conditions by using big data collected from historical flight information of military aircraft supplied by Korean manufacturers and meteorological information from the Korea Meteorological Administration. In addition, by deriving flight rules according to weather information, it was possible to discover an efficient flight schedule establishment method in consideration of weather information. Design/methodology/approach This study is an analytic study using data mining techniques based on flight historical data of 44,558 flights of military aircraft accumulated by the Republic of Korea Air Force for a total of 36 months from January 2013 to December 2015 and meteorological information provided by the Korea Meteorological Administration. Four steps were taken to develop optimal flight prediction models and to derive rules for flight implementation and cancellation. First, a total of 10 independent variables and one dependent variable were used to develop the optimal model for flight implementation according to weather condition. Second, optimal flight prediction models were derived using algorithms such as logistics regression, Adaboost, KNN, Random forest and LightGBM, which are data mining techniques. Third, we collected the opinions of military aircraft pilots who have more than 25 years experience and evaluated importance level about independent variables using Python heatmap to develop flight implementation and cancellation rules according to weather conditions. Finally, the decision tree model was constructed, and the flight rules were derived to see how the weather conditions at each airport affect the implementation and cancellation of the flight. Findings Based on historical flight information of military aircraft and weather information of flight zone. We developed flight prediction model using data mining techniques. As a result of optimal flight prediction model development for each airbase, it was confirmed that the LightGBM algorithm had the best prediction rate in terms of recall rate. Each flight rules were checked according to the weather condition, and it was confirmed that precipitation, humidity, and the total cloud had a significant effect on flight cancellation. Whereas, the effect of visibility was found to be relatively insignificant. When a flight schedule was established, the rules will provide some insight to decide flight training more systematically and effectively.

• 한국시뮬레이션학회논문지
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• 제28권4호
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• pp.33-43
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• 2019

Link-16은 미 해군 및 공군, NATO에 합동 상호운용성을 제공하는 데이터링크로 국내 무기체계에서도 운용되고 있다. 현재 Link-16 운용을 위한 시험환경, 전술모의훈련 및 상호운용성 검증 시험은 해외 SW 및 도구를 통해 전적으로 의존하고 있다. 따라서 Link-16 기반의 운용환경시험 도구의 개발이 필요하다. 본 논문에서는 Link-16 해외도구 기능 분석을 통해 Link-16 네트워크 운용성능분석 시뮬레이터를 개발하였다. 또한 연동을 위한 SIMPLE 표준 인터페이스를 구현하였다. Link-16 네트워크 운용성능분석을 위한 기능모델은 사전분석, 실시간 운용분석, 사후분석 기능모델로 구성된다. 각 기능모델에 대한 시험은 해외 SW 및 도구와 SIMPLE 연동을 통해서 수행하였다. Link-16 네트워크 운용성능분석 시뮬레이터를 통해 해외 SW를 대체하게 된다면 우리 군에 맞는 전술훈련 및 네트워크 운용성능분석, 운용(시나리오)검증을 수행할 수 있을 것이다.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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• pp.468-476
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• 2001

The ROK TRANSCOM is trying to establish a concrete wartime sealift operation plan. But there are many problems to be solved for setting up the plan. The most serious problem is to procure war materiel to be shipped in U.S.A and next one is to determine the number of sealift assets and to allocate them. The process of sealift operation can be described as follows. Before the order of vessel mobilization, all vessels appointed for activation would be scattered in worldwide in the state of Beaded or unloaded. After the order of vessel mobilization, vessels would go to SPGE(seaport of embarkation) to load war materiel. Some loaded ships should offload the commercial cargo to the near port as soon as they are activated, before they would go to SPOE. All vessels would load procured materiel in SPOE and then go to SPOD(seaport of debarkation). They would offload war materiel in SPOD and then go back to SPOE to load war materiel again. We will simulate this process using ARENA(1), evaluate the sealift capability of ROK and find omit problems of the sealift plan. This model ultimately evaluates the sealift capability and provides planners with critical information far establishing and correcting the plan. This study can also provide military planners with a flexible and accessible decision support tool to provide advance planning under a variety of conditions on the sealift capability. The military planner is expected to make use of this model as a standard for establishing effective and concrete sealift operation in the near future. We can conclude how procurement capability significantly affects the result of sealift operation through this model. We could decide the appropriate levee of sealift asset such as the number of vessels and the number of available berth. So we could allocate effectively the resources for completing the sealift operation within the TGT(Target) time.