• Title/Summary/Keyword: air defense

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The Multi-Net Performance Evaluation of Link-16 in the L-Band Sharing with Radars (L-대역 내 레이더 주파수 공동사용 환경에서 멀티넷을 통한 Link-16 운용 가능성 성능 평가)

  • Choi, Seonjoo;Yu, Jepung;Lim, Jaesung;Baek, Hoki;Kim, Jaewon;Choi, Hyogi
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.7
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    • pp.738-746
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    • 2016
  • As the trend of future war has been changed to network centric warfare, tactical data link should be needed for fast and accurate situation awareness. Nowadays, Korean air force conducts military operations by using aircrafts equipped with Link-16. The Link-16 can conduct multiple mission at the same time because it supports multi-net capability. Due to lack of frequency resource, the way to share the frequency with other systems has been studied and using L band with radar is considered as one of the candidates bands. However, the data link can be affected by the interference from radars when it shares the L-band because the L-band in Korea is already assigned to long-range detection radars. In this paper, we evaluate operational possibilities of tactical data link in the L-band based on Link-16.

Effect of Operating Condition of Airblast Atomizer on Twin spray characteristics and interaction (공기충돌형 연료분사장치의 운용조건이 이중분무특성과 간섭효과에 미치는 영향)

  • Park, S.G.;Han, J.S.;Kim, Y.;Park, J.B.
    • Journal of the Korean Society of Propulsion Engineers
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    • v.3 no.1
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    • pp.9-14
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    • 1999
  • The effect of operating condition was studied experimently on the characteristics of twin sprays ejected from two airblast atomizers, within the range of the mass air-fuel ratio 1.36∼3.54. Water and nitrogen gas were used as test fluids for the experiments. Spray characteristics of liquid spray were measured with measurement of mass distribution and instantaneous image of the spray cone. Experimental results show that the maximum specify of the distribution were lowered but distributed over the larger area when the ROA ratio increased, Center of mass position did not change with increasing water mass flow, Increase of the nozzle distance has an small effect on mass distribution of interaction area but distributed over the larger area. It was also conformed that the effect of interaction near central point of collision decreased with the increase of the ROA ratio on interaction area from comparison using superposition method

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The Study on the Woman Soldier Human Affairs Operation Systems. (여군 인사운영시스템에 관한 연구)

  • Jung, Jae-Keak
    • Convergence Security Journal
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    • v.15 no.3_1
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    • pp.31-39
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    • 2015
  • The Female workforces opened the combatants which was not allowed so far including the artillery in the army, air defense, and etc. to the woman soldier in 2014. I exceeded 10,000 people in 2015 and it is in the plan to be expanded to 4,450 officers, 6,374 noncommissioned officers in 2017. A navy is the plan which selects the woman officer to board a submarine since 2017 and which I board over 3,000 t level in a submarine. But the institutional supplementation about this is insufficient although the woman soldier increased depending on the policy's decision. The role of the woman soldier was expanded and it was the time when the system developmental about the woman soldier management which is consistent with the future war aspect will have to be guaranteed, and the clear standard including the post circulation to the starting in advance of the woman soldier and human resource expansion and treatment, and etc. is required. I supplement the current regulation which I am applying as man soldier Army and the same standard although the woman soldier and man soldier Army has a difference and I analyze the phenomenon and the developmental solution should be suggested about the woman soldier people management.

Design of the 1.5kVA Class Wireless Power Transfer Device for Battery Charging of Integrated Power Control System in MSAP (군 이동기지국시스템(MSAP) 통합전원제어장치 배터리 충전용 1.5kVA급 무선전력전송기기의 설계)

  • Kim, Jin-Sung;Kim, Byung-Jun;Park, Hyeon-Jeong;Seo, Min-Sung
    • The Journal of the Korea institute of electronic communication sciences
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    • v.15 no.3
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    • pp.413-420
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    • 2020
  • The Tactical Information and Communication Network system provides real-time multimedia services such as voice and data by utilizing the Mobile Subscriber Access Point. At this time, an external transmission path is constructed through the Low Capacity Trunk Radio and the High Capacity Trunk Radio system. The communication devices of each wireless transmission system are mounted on a tactical vehicle and a secondary battery is used to prevent a power interruption when the supply power to the tactical vehicle is transferred to the integrated power control device. In this paper, the basic design of the Wireless Power Transfer device for charging the battery of the integrated power control system of the mobile base station system using the Loading Distribution Method and checking the number of primary windings and the core material selection by the air gap through the Finite Elements Method.

Physical-Chemical Properties of Graphite Foams Produced with Fluorinated Mesophase Pitch (불소화 메조페이스 핏치로 제조된 그라파이트 폼의 물리/화학적 특성)

  • Kim, Ji-Hyun;Kim, Do Young;Lee, Hyung-Ik;Lee, Young-Seak
    • Korean Chemical Engineering Research
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    • v.54 no.6
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    • pp.830-837
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    • 2016
  • In order to improve the compressive strength of graphite foams (GFms), mesophase pitch (MP) was stabilized in air atmosphere and then fluorinated at different conditions. The Fluorine/Carbon (F/C) in surface-chemical contents of fluorinated MP has range of 23.75%~61.48% according to the different fluorine partial pressure. The compressive strengths of GFms prepared from fluorinated MP were increased in proportion to the apparent densities. The compressive strength of the GFm produced from MP with 35.93% of F/C (%) showed maximum value in $2.93{\pm}0.06MPa$, which was increased up to 27.95% than that of the GFm prepared from un-fluorinated MP. This result was attributed that the interface bonding between of MPs due to fluorine functional groups with high surface energy helped to improve compressive strength of the GFm.

Pattern Analysis and Determination of Body Dimension for Flight Suit Design (비행복 설계를 위한 패턴 분석 및 인체치수 설정)

  • Jeon, Eun-Jin;Park, Ji-Eun;Jeong, Jeong-Rim;Park, Sei-Kwon;Park, Jang-Un;You, Hee-Cheon;Kim, Hee-Eun
    • Fashion & Textile Research Journal
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    • v.11 no.2
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    • pp.286-292
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    • 2009
  • The purpose of this study is to analyze the pattern of the present flight suit, to select variables of human body and key dimensions for making pattern of the flight suit, and to decide the most appropriate size of human body and rate of ease for designing an overall flight suit. For analyzing the pattern of flight suit, we used "M95Special" (men ; chest circumference 92-97 cm ; height : above 177 cm), which was indicated as the standard of the Ministry of National Defense. We analyzed general appearance and the actual dimensions of the pattern of the flight suit. As a result of analyzing the pattern, flight suit was front-opened overall style which had a flat collar with rounded edges, two-pieced sleeves with lower height of the sleeve's cap, 3cm-width belt on the waist and 8 pockets. To decide the most appropriate size of human body, we selected 20 variables of human body in the 359 variables of the Size Korea by referring the previous studies. The 20 variables of human body were 9 circumferences (chest, waist, hip, neck, armscye, wrist, thigh, knee, and ankle), 9 lengths (stature, back interscye fold, waist back, crotch height, crotch, body rise, arm, outside leg and total), and 2 breadths (biacromial and chest). We drew out the size of 20 variables from the Size Korea and US Army anthropometry data and decided the most appropriate values from the drawn data for applying to the pattern of flight suit.

A Case Study on Safety Analysis Procedure of Aircraft System using the Relex (Relex를 이용한 항공기 시스템 안전성 평가 절차 사례분석)

  • Lee, Dong-Woo;Kim, Ip-Su;Na, Jong-Whoa
    • Journal of Advanced Navigation Technology
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    • v.22 no.3
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    • pp.179-188
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    • 2018
  • In developing avionics systems, safety analysis and evaluation specified in SAE ARP4761 (Methods and Guidelines for Civil Aviation System and Equipment Safety Assessment Process) are carried out to prevent air accidents. Safety analysis requires knowledge of the abnormal state of the system, not its normal state, and its interrelationships with other standards. Therefore, a tool that automatically outputs data which proves compliance with safety certification standards is required. In this study,In this study, Schematized the safety analysis procedure of the specification and studied the method of applying the safety analysis CAD tools to individual procedure. As an example study, ARP4761 analysis was performed on the wheel brake system (WBS) of the ARP4761 appendix.

A Methodology for Evaluating Mission Suitability of Manned-Unmanned Aircraft Teaming for SEAD Missions (SEAD 임무 수행을 위한 유x무인기 협업 체계의 임무적합도 평가 방법론 연구)

  • Seo, Wonik;Lee, Hyun Moo;Kim, Jeong-Hun;Choi, Keeyoung;Jee, Cheol-Kyu
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.48 no.11
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    • pp.935-943
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    • 2020
  • This paper presents a methodology for evaluating suitability of a manned-unmanned aerial vehicle team for a complicated mission. The study identified vehicle performance, equipment performance and level of autonomy as the key factors that affect the mission effectiveness. A manned and an unmanned aircraft were compared, and their performance was quantized in these respects. SEAD was chosen as a representative manned-unmanned team mission. The SEAD mission was broken down to a sequence of tasks. Mission experts evaluated the importance of each mark item for the mission legs. Combining the results showed proper type of aircraft for each leg depending on the complexity, safety, and importance of the task. Finally, the whole mission plan was laid out as a time-based sequence which alleviate pilot workload significantly.

Core Technologies of the X-51A SED-WR Program (X-51A 스크램제트 기술 실증기 개발 프로그램 핵심 기술)

  • Noh, Jin-Hyeon;Won, Su-Hee;Parent, Bernard;Choi, Jeong-Yeol;Byun, Jong-Ryul;Lim, Jin-Shik
    • Journal of the Korean Society of Propulsion Engineers
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    • v.12 no.5
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    • pp.79-91
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    • 2008
  • The present article is intended to introduce the X-51A Scramjet Engine Demonstrator-Wave Rider (SED-WR) program and its core technologies to the korean propulsion community. The X-51A program is lead by the U.S. Air Force Research Laboratory (AFRL) and is sponsored by the U.S. Defense Advanced Research Projects Agency (DARPA). Most of the contents is taken from the paper by Hank et al.[1] with the supplemental materials from additional references. X-51A is a hypersonic experimental vehicle for the flight test of the hydrocarbon fuel-cooled scramjet engine developed by the AFRL HyTech program. The scramjet engine and the hypersonic flight technologies may enter the era of practical use by the completion of the ground tests in 2008 followed by the flight tests scheduled in 2009.

Redox Behavior of Chromium Oxide-Zirconia Catalyst (산화크롬-질코니아 촉매의 산화-환원거동)

  • Sohn, Jong-Rack;Ryu, Sam-Gon
    • Applied Chemistry for Engineering
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    • v.3 no.4
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    • pp.663-669
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    • 1992
  • Chromium oxide/zirconia catalysts were prepared by dry impregnation of $Zr(OH)_4$ powder with aqueous solution of $(NH_4)_2CrO_4$ followed by calcining in air. The redox behavior of prepared catalysts were investigated by reacting cumene as test material over catalysts. As a result it was found that $Cr^{6+}$ species(as chromate) on the surface of catalyst was responsible for the formation of strong acid site and the catalytic activity for the dealkylation of cumene. However, much of the $Cr^{6+}$ species was reduced to $Cr^{3+}$ species by $H_2$ formed during the catalytic reaction of cumene and the reduced $Cr^{3+}$ species was an active site for dehydrogenation of cumene to form ${\alpha}$-methyl styrene. The reduced $Cr^{3+}$ species was also reoxidized to a $Cr^{6+}$ species after treatment with $O_2$ and consequently the deoxidized catalyst exhibited catalytic activity for the dealkylation reaction of cumene.

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