해양경찰청 경비함정의 선박용 디젤기관은 MTU와 Pielstick사의 고출력 엔진으로 윤활유의 성능이 매우 중요하다. 경비함정 엔 진의 부하변동이 많고 운행시간 등이 증가되면서 열에 의한 산화 및 연료유, 수분 등 혼입으로 동점도 등 윤활유 성질이 변할 수 있다. 본 연구에서는 윤활유의 열화요인 및 영향을 파악하기 위해 경비함정 윤활유를 사용 시간별(100, 200, 300, 400 hr)로 채취하였다. 채취된 윤활유로 열화요인 분석 위해 연료 혼입량 등을 측정하였다. 또한 열화 영향 분석을 위해 동점도 등을 측정하였다. 특히 윤활유의 산화 여부를 분석하기 위해 산화 안정도 등을 확인하였다. 열화의 외부요인인 연료 혼입량의 경우 사용 시간이 늘어나면서 5.1%에서 14.0%로 증가하였으며, 이에 따라 동점도는 낮아지는 결과를 보였다. 윤활유의 사용 시간이 늘어나면서 열 및 수분 혼입에 의한 산화는 확인할 수 없었다.

This study proposes a construction plan for the Korea Navy's next-generation TSCE(Total Ship Computing Environment) based destroyers to address rapidly evolving maritime threats and decreasing military manpower. It focuses on system integrated ship construction based on TSCE for quick response time with fewer operators, improving the efficiency of systems and Equipments installed in the ship. The methodology includes analyzing TSCE-based system integration theories and levels. also analyze system integration in U.S. Navy’s Zumwalt destroyers and Littoral Combat Ships, conducting expert surveys to build consensus on system integration methods, proposing operational efficiency improvements through TSCE-based system integration. Additionally, we propose an architecture of TSCE with real time OA(Open Architecture) from both functional and physical perspectives, verified through Python simulations. The study suggests optimal crew sizes for next-generation destroyers through comparative analysis of TSCE based integration types. It emphasizes the importance of system integration in naval ship construction, presenting specific measures to enhance operational efficiency and optimize crew operations. The findings are expected to contribute significantly to enhance the future naval capabilities of the Korea Navy.

This paper aims to introduce a case of improving the performance of aged naval ships' Identification Friend or Foe(IFF) equipment from Mode 4 to Mode 5, thereby enhancing operational capabilities and overcoming integration limitations. Since 2019, South Korea has been conducting a project to replace IFF equipment across the entire military, categorized into naval ship, air force aircraft, surveillance and reconnaissance, and protection. Among these, three naval classes without combat systems required not only an upgrade of their IFF equipment from Mode 4 to Mode 5 but also an integration capability that would allow them to maintain the same fire control procedures by linking with existing naval gun fire control systems. To implement this integration function, the signal processing methods of the existing IFF equipment were analyzed, and based on this, the integration function was implemented in a signal converter module. This paper is expected to serve as an important resource for future performance upgrades of internal equipment in aged naval ships.

Reducing underwater radiated noise from a ship is a critical issue for ensuring the survivability of the vessel. As high-speed signal processing and interlocking algorithms become more sophisticated, the heat intensity of shipboard equipment is increasing per unit volume. When designing shipboard equipment, it is necessary to consider the trade-off between heat dissipation and noise reduction. Following an analysis of the trade-offs, it was determined that the arrangement of Fan Ass'y A and B exhibited excellent noise and heat dissipation characteristics. Based on this, PWM control operating zones were derived. It was determined that the placement of Fan Ass'y A and B in the operating zone would increase the PWM duty cycle from 33% to 58% using a signal frequency of 25kHz band with guaranteed reliability. This would increase the noise by approximately 9dB(A) but reduce the internal board reference temperature by up to 15℃.

As technologies have been more quickly developed in this 4th Industry Revolution era, their application to defense industry has been also growing. With these much advanced technologies, we attempt to use Manned-Unmanned Teaming systems in various military operations. In this study, we consider the Location-Routing Problem for reconnaissance surveillance missions of the maritime manned-unmanned surface vehicles. As a solution technique, the two-phase method is presented. In the first location phase, the p-median problem is solved to determine which nodes are used as the seeds for the manned vehicles using Lagrangian relaxation with the subgradient method. In the second routing phase, using the results obtained from the location phase, the Vehicle Routing Problems are solved to determine the search routes of the unmanned vehicles by applying the Location Based Heuristic. For three network data sets, computational experiments are conducted to show the performance of the proposed two-phase method.

Maintaining sea superiority through successful mission accomplishments of warships is being proved to be an important factor of winning a war, as in the Ukraine-Russia war. in order to ensure the ability of a warship to perform its duties, the survivability of the warship must be strengthened. In particular, among the survivability factors, vulnerability is closely related to a damage assessment, and these vulnerability data are used as basic data to measure the mission capability. The warship's mission capability is usually measured using a wargame model, but only the operational effects of a macroscopic view are measured with a theater level resolution. In order to analyze the effectiveness and efficiency of a weapon system in the context of advanced weapon systems and equipments, a warship's mission capability must be measured at the engagement level resolution. To this end, not the relationship between the displacement tonnage and the weight of warheads applied in the theater level model, but an engagement level resolution vulnerability assessment method that can specify physical and functional damage at the hit position should be applied. This study proposes a method of measuring a warship’s mission capability by applying the warship vulnerability assessment method to the naval engagement level analysis model. The result can be used as basic data in developing engagement algorithms for effective and efficient operation tactics to be implemented from a single unit weapon system to multiple warships.

In this study, we performed thermal safety design of the electric module of a heat-loaded equipment with consideration of its heat dissipation performance. Initially, we calculated the heat dissipation of natural convection to choose a cooling method. Based on this, we found that some modules required forced convection and selected an air-cooling method with an outdoor temperature of 43 degrees Celsius, which is the maximum temperature in Korea. Prior to module production, we performed thermal analysis of each module and proceeded with a design to increase the thermal conductivity of the module as a primary step, and subsequently proceeded with Heat Sink design to maximize the heat dissipation performance. After considering various constraints according to the system requirements and designing the cooling path, we experimentally and analytically secured thermal safety at the operating temperature of the equipment.

수많은 함정용 채프들은 폭발에 의해 확산되어 채프운을 형성하며, 채프운은 허위 레이더 반사 단면적을 생성하여 적의 레이더를 기만한다. 본 논문에서는 전산유체역학-이산요소법 단방향 연동 기법을 기반으로 공기 중에 분포하는 함정용 채프운의 시공간 분포 를 해석하는 수치적 프레임워크를 구축하고 바람의 방향과 속도, 채프 카트리지의 초기 각도와 폭발 압력이 채프운 분포에 미치는 영 향을 분석하였다. 채프운의 확산은 폭발에 의한 방사형 확산, 난류와 충돌에 의한 전 방향 확산, 낙하 속도 차이에 의한 중력 방향 확산 과 같이 세 단계로 구분되는 것을 확인하였다. 바람은 채프운의 평균 위치를 이동시켰으며, 항력에 의한 확산 효과는 나타나지 않았다. 카트리지 초기 각도에 따라 폭발에 의한 방사형 확산 방향이 달라졌으며, 각도가 지면과 수직에 가까울수록 더 넓게 확산되었다. 폭발 압력이 증가할수록 채프운은 더 넓게 확산되었으나 중력 방향으로는 분포 차이가 작았다.

Gas turbine engines are widely used as prime movers of generator and propulsion system in warships. This study addresses the problem of designing a DS-based PID controller for speed control of the LM-2500 gas turbine engine used for propulsion in warships. To this end, we first derive a dynamic model of the LM-2500 using actual sea trail data. Next, the PRC (process reaction curve) method is used to approximate the first-order plus time delay (FOPTD) model, and the DS-based PID controller design technique is proposed according to approximation of the time delay term. The proposed controller conducts set-point tracking simulation using MATLAB (2016b), and evaluates and compares the performance index with the existing control methods. As a result of simulation at each operating point, the proposed controller showed the smallest in , which means that the rpm does not change rapidly. In addition, IAE and IAC were also the smallest, showing the best result in error performance and controller effort.

Naval weapons systems of the Republic of Korea are acquired through the Defense Planning Management System. Recently, acquisition of some naval ships have been delayed, and the causes of the delays have been recognized as inappropriate project management at the Execution Phase. However, we argue that the delay problem in naval ships acquisition should be approached, with due regard for the entire Defense Planning Management System. That is, We should try to investigate from Planning Phase to those of Programming, Budgeting and Execution Phases. Therefore, in this study, we investigated the actual cases of the delay in naval acquisition at all phases of the Defense Planning Management System. Based on the investigation, we tried to identify the naval ship Acquisition Delay Factors and find out the Weights of those factors. As the next step, we calculated the Influence Measures on the naval missions, including the Cost of Naval Capability Gap derived from the delays in acquisition of naval ships. As a final step, we calculated the Acquisition Delay Measures based on the interrelationship between the Acquisition Delay Factors and the Influence Measures. Then we evaluated and analyzed what the results stand for. Finally, we made suggestions for future improvement. The improvement suggestions we made for preventing delay in acquisition of naval ships in this study are as follows. First, we need a shift in perception. It is necessary to measure the Acquisition Delay Factors in acquiring naval ships and manage them from the Planning Phase. Second, resolution must be concerted efforts. All relevant agencies, not just a few, should work together to resolve the problems of acquisition delay. Third, analysis must be based on the accumulation of data. This allows the elaborating of naval ship Acquisition Delay Factors and Delay Measures. If this research method is applied to other military weapons systems in the future, we may be able to not just identify the Acquisition Delay Factors in acquisition of other military weapons systems, but also pursue improvement in those cases.

In a series of recent launch tests, North Korea has been improving the firepower of its missiles that can target South Korea. North Korea’s missiles and submarines are capable of threatening targets in South Korea and are likely faster and more covert than the systems previously seen in North Korea. The advanced threats require that ROK Navy should not only detect them earlier than ever but also response quicker than ever. In addition to increasing threats, the number of young man that can be enlisted for military service has been dramatically decreasing. To deal with these difficulty, ROK navy has been making various efforts to acquire a SMART warship having enhanced defense capability with fewer human resources. For quick response time with fewer operators, ROK Navy should improve the efficiency of systems and control tower mounted on the ship by promoting the Ship System Integration. Total Ship Computing Environment (TSCE) is a method of providing single computing environment for all ship systems. Though several years have passed since the first proposal of TSCE, limited information has been provided and domestic research on the TSCE is still in its infancy. In this paper, we apply TSCE with open architecture (OA) to solve the problems that ROK Navy is facing in order to meet the requirements for the SMART ship. We first review the level of Ship System Integration of both domestic and foreign ships. Then, based on analyses of integration demands for SMART warship, we apply real time OA to design architecture for TSCE from functional view and physical view. Simulation result shows that the proposed architecture has faster response time than the response time of the existing architecture and satisfies its design requirements.