• Korean Journal of Metals and Materials
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• v.49 no.2
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• pp.174-179
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• 2011

We investigated the surface morphology changes of a lithium/sulfur battery using multi-walled canbon nanotube added sulfur electrode during charge-discharge cycling. The Li/S cell showed the first discharge capacity of 1286 mAh/g-S, which utilized is 71% of the theoretical value. It decreased to 328 mAh/g-S at the 100th cycle, which corresponds to about 19% utilization of the total sulfur in the cathode. The spherical lumps of the reaction product were observed on the surface of the sulfur electrode. This material was verified as lithium sulfide by X-ray diffraction measurement. The pores in the separator were filled with reaction product. Thus the diffusion of the $Li^+$ ion decreased, which resulted in the decreased capacity of the Li/S cell.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.6
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• pp.322-330
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• 2020

This study deals with underwater explosion (UNDEX) characteristics of various non-explosive underwater shock sources for the development of non-explosive underwater shock testing devices. UNDEX can neutralize ships' structure and the equipment onboard causing serious damage to combat and survivability. The shock proof performance of naval ships has been for a long time studied through simulations, but full-scale Live Fire Test and Evaluation (LFT&E) using real explosives have been limited due to the high risk and cost. For this reason, many researches have been tried to develop full scale ship shock tests without using actual explosives. In this study, experiments were conducted to find the characteristics of the underwater shock waves from actual explosive and non-explosive shock sources such as the airbag inflators and Vaporizing Foil Actuator (VFA). In order to derive the empirical equation for the maximum pressure value of the underwater shock wave generated by the non-explosive impact source, repeated experiments were conducted according to the number and distance. In addition, a Shock Response Spectrum (SRS) technique, which is a frequency-based function, was used to compare the response of floating bodies generated by underwater shock waves from each explosion source. In order to compare the magnitude of the underwater shock waves generated by each explosion source, Keel Shock Factor (KSF), which is a measure for estimating the amount of shock experienced by a naval ship from an underwater explosionan, was used.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.2
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• pp.98-107
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• 2002

An experimental and numerical study of aerodynamic charateristics of KSR-III and jet impingement on a deflector during launch has been conducted. To investigate aerodynamic characteristics of KSR-III configuration, wind tunnel tests using 6.4% scale model were performed by 4x4 feet ADD trisonic wind tunnel on the Mach number range of 0.4~3.8. Solutions of Three dimensional Euler equations were also obtained and compared with test result. For the study of KSR-III jet impingement flowfield on a deflector during launch operation, unsteady computation using CFD-FASTRAN was performed.

• The Optical Journal
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• s.158
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• pp.52-54
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• 2015

최근 무인항공기를 지칭하는 드론 관련 산업이 미래를 이끌 신산업으로 부상하고 있다. 드론은 20세기 초에 군사용으로 개발되어 정찰 감시 및 폭격과 같은 군사임무를 수행하여 왔으나 최근 들어 독일 DHL, 아마존, 구글 등과 같은 다국적 기업들이 상업적 용도로 활용을 선언하며 연구 개발에 뛰어 들면서 그 시장이 예상보다 빨리 커지고 있다. 미국 틸 그룹의 보고서에 의하면 2013년 세계 드론 시장의 규모는 66억 달러였고 그 중 군사용이 90% 이상을 차지하고 있으나 향후 민수용 시장 비율이 상당히 커질 것으로 예상된다. 2022년에는 114억 달러 규모로 커질 것으로 예상하고 있다. 현재 민수용으로 사진 촬영용 소형 드론으로부터 정밀농업, 인프라 관리, 택배 및 화물 수송 등으로 운용 범위를 확대하고 있다. 국내 드론 산업은 군수 위주로 시작되어 세계 7위권의 기술력을 확보한 것으로 평가되고 있다. 무인기 분야의 연구개발은 국방과학연구소와 한국항공우주연구원 등 정부출연연구소가 주도하는 가운데, 한국항공우주산업, 대한 항공이 주로 체계종합(System Integrator) 및 비행체 개발을 담당하고 LIG넥스원, 삼성탈레스, 삼성테크윈 등의 대기업을 포함한 중소업체들이 부체계 기술을 개발하고 있다. 최근 소형 드론을 중심으로 시장형성이 가시화되는 민수 시장에서는 가격, 기술 경쟁력의 열위에 있어, 국내 산업 경쟁력 확보와 미래 시장을 선도할 핵심 제품 개발이 시급한 실정이다. 또한 무인기의 비행체 국산화는 상당한 수준으로 진행되었으나, 광학(EO) 적외선(IR) 카메라 등 핵심 부가가치를 구성하는 탑재 임무장비의 경우 원천기술의 부족으로 해외에 의존하고 있다.

• Journal of National Security and Military Science
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• s.9
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• pp.191-206
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• 2011

This study is presented a scheme that information security research institutions located within the central area can be participated actively m national defense information security industry. The many of information security company are located in the central region(Daejeon) and there are many research institutes. However, the participation rate of the Defense Information Security Industry is not high compared to other provinces. Although a variety of reasons, there are no the Defense Privacy Office that could have a role in protocol and the information about the industry. In addition, the Department of Defense related to national defense information security industry have not information about research institutions in the central region and are not well to identify the characteristics of institutional technology and research. So in this paper we presented some of the alternatives. 1) Building Pool involved in information security research according to the characteristics of each agency 2) Constitute the research community between Research institutions and the company 3) Build the technology cooperation between research institutions and the defense research institutes 4) Utilization of industry/university/research institutes related to Information Security Industry 5) Make strategic alliances among research institutes based on technical expertise.

• Journal of National Security and Military Science
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• s.13
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• pp.43-81
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• 2016

Security environment we face in the Korean Peninsula is unexpectable. Tensions between Seoul and Pyeongyang and its threats are continuously evolving. Kim Jung Un will keep on conducting provocations and DPRK's isolation will result uncertainty to their objective and intention. KPA is centered on ground forces with conventional weapons but they possess modernized missiles and nuclear capabilities. What's more concerning is that North Korea continuously pursue and develop nuclear weapons and missile capabilities. Pursuing defense reform is inevitable for the ROK to deal adequately against the security threats posed by the North and to prepare for the environment of future warfare. If we are satisfied with the current capabilities then our military capabilities and security status will retrogress. We have to reorganize our units to make a small but FMC, smart military organization. Organization analysis is an urgent issue for reorganizing units. However, it isn't an easy task to reform an organization. There are vague parts for analysis and strong resistance from the people within the organization. Therefore should not focus on the reduction of people and the organization. Organization reform should be done with the acknowledgement of most of the personnel and should focus on the task and its method. These should be reflected to the organization analysis.

• Journal of National Security and Military Science
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• s.3
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• pp.35-72
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• 2005

The purpose of this paper is to recommend the Ministry of Defense(MOD) for revolutionizing the current defense education system. As an instructor and an education planning officer of the ROK Army College, for last dozen months, the author has been embarrassed whenever tried to figure out what would be the role, functions, and educational goals of the college. In a nutshell, there has not been any general guidance for educating field grade officers. This unbelievable defect mainly comes from the absence of a responsible organization in the MOD. Even though it has the education branch under the department of personnel affairs, it doesn't have capabilities to design and implement the consistent and valuable education policy. Therefore, the development of defense education should begin with reinforcing the organization and functions of the MOD education branch. We need more experts on education( i.e. Ph.Ds of Education) and experienced specialties on defense education so that we could develop the overall guidance for military professional education. In addition, we need to enact the "defense or military education act" in a tentative name. This will ensure the legitimacy and continuity of defense education guidance initiated by the MOD. In a conclusion, it is senseless to think the blueprint for the Army College out until the preconditions mentioned above are matured. We must begin with rectifying the higher educational system.

• Journal of National Security and Military Science
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• s.2
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• pp.261-283
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• 2004

To build up the military strength based on information oriented armed forces, the Korean ministry of national defense (MND) promotes the defense CALS (Continuous Acquisition and Life cycle Support) initiative for the reductions of acquisition times, improvements of system qualities, and reductions of costs. These defense CALS activities are the major component of the underlying mid and long term defense digitization program and the ultimate goal of program is to bring a quick victory by providing real-time battlefield intelligence and the economical operations of the military. The concept of defense CALS is to automate the acquisition and disposition of defense systems throughout their life cycle. For implementing defense CALS, the technology for exchange and sharing CALS standard data that is created once and used many times should be considered. In order to develop an efficient CALS information exchange and sharing system, it is required to integrate distributed and heterogeneous data sources and provide systematic search tools for those data. In this study, we developed a content based search engine technology which is essential for the construction of integrated data environments. The developed technology provides the environment of sharing the CALS standard data such as SGML(Standard Generalized Markup Language) and STEP(Standard for The Exchange of Product model data). Utilizing this technology, users can find and access distributed and heterogeneous data sources without knowing its actual location.

• Electronics and Telecommunications Trends
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• v.30 no.4
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• pp.92-101
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• 2015

미래 전장은 정보 지식 기반의 첨단 전력체계를 확충하기 위해 향후 전력구조를 통합, 지휘통제통신(C4I) 체계와 생존성과 통합성이 향상된 전장의 네트워크중심전(NCW) 수행능력을 향상시킬 것이다. 사이버물리시스템(Cyber-Physical Systems: CPS)은 함정전투체계에 적용되고 있는 DDS를 포함하여 국방 M&S의 근간인 Live, Virture, Constructive(L-V-C) 체계의 큰 축을 형성하고 있다. 사물인터넷(Internet of Things: IoT) 기술은 센서네트워크, 통신, Radio Frequency Identification(RFID), Ubiquitous Sensor Network(USN), Machine to Machine(M2M), D2D 기술 및 상황인지, 지능서비스를 위한 정보수집/가공/융합/분석/예측기술을 포괄적으로 포함한 기술로서 미래산업을 이끌어 갈 차세대 선도 기술이며, 특히 군사적으로도 감시정찰 센서네트워크(USN), 견마형로봇, 경전투로봇과 무인기 기술 및 전술정보통신망체계(TICN) 등 첨단 통신네트워크 기술의 전력화 추세는 IoT 기술의 적용영역을 넓혀주고 있다. 감시정찰체계(Sensor)에서는 감시정찰 분야 영상정보 처리, 표적탐지 등과 관련된 IoT 기술 소요와 지휘통제통신(C4I) 체계의 상호운용성, 데이터링크, 지능형 통신체계 등 C4I 관련 IoT 기술 소요 및 타격체계(Shooter)의 내장형 SW 등 유 무인 무기체계 관련 IoT 기술의 소요가 증대될 것으로 예상된다. 본고는 CPS 및 IoT 기술의 군사적 활용방안 및 획득전략에 대한 적용기술 및 발전방향을 살펴본다.

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.5
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• pp.607-615
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• 2019

In this paper, the electromagnetic effects on the discontinuity structures of the frequency selective radome in manufacturing process based on the X-band were analyzed. In order to fabricate a curved radome using a planar frequency selective surface structure, it is assumed that gaps, slanted gaps, pattern damage, and pattern misalignment between FSS patterns, which are discontinuous elements that can occur at the joint surface of the FSS panel. FSS specimens including continuous elements were fabricated and the frequency transmission characteristics were measured in a free space measurement environment. From the measurement results, resonance frequency shift, transmission performance degradation, and bandwidth variations were found to be the largest when the damaged pattern was bonded to the junction of FSS panels.