• Defense and Technology
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• no.7 s.233
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• pp.60-69
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• 1998

독일 HDW조선소의 Bonn 지사장으로 근무중인 Udo Ude씨는 209급 잠수함 해외수출 성공사례를 다음과 같이 분석하였다. -1970년 독일해군용 206급 계약시 잠수함을 해군에 인도하기 전까지의 모든 과정을 조선소가 직접 책임지고 수행토록 하는 General Contractor Principle(총괄계약자 원칙)에 의해 확보된 기술인력, 자재/장비 공급원 발굴, 축적된 장비간 연동과 체계통합 기술 및 경험 –대부분의 탑재 장비를 국내 방산업체로부터 조달할 수 있는 탄탄한 국내 기술력 –매 신규사업마다 성능향상을 위한 과제선정 및 계속적인 연구 –정부 소유 시험시설 및 장비 활용과 제반 기술관리에 있어서 민.관.군의 적극적이고 긴밀한 지원체제 구축 이러한 성공사례 분석에 독일 현지에서 느낀 필자의 경험소감을 추가하면 다음과 같다. –규정을 잘 지킬 뿐만 아니라 타인의 잘못을 즉시 일깨워 주는 준법정신 및 고발정신 -2-3년 후의 휴가계획까지 수립하여 준비할 정도의 처절한 사전계획 및 준비정신 –불결한 것과 게으름을 참지 못하는 청결성 및 근면성 –누구든지 원하면 경제적인 부담없이 평생동안 공부할 수 있는 교육제도 –게르만족이 우월하다는 내면적 자부심 –작은 일이라도 모여서 토의하고 결론을 도출하기 좋아하는 공동체 의식 –약속을 철저히 지키는 정직성 –과거의 사실이나 유물을 철저히 보존하는 역사의식 –모든 분야에서 철저하게 운용되는 Meister(장인)제도 등

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.2 s.25
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• pp.20-25
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• 2006

Low frequency towed line array with high array gain and beam resolution is a long range surveillance sensor for anti-submarine warfare. The beam characteristics is however deteriorated due to the distorted line array sensor caused by low towing speed, wind, current, and towing ship maneuvering. An adaptive beamforming method is utilized in this paper to enhance the distorted line array beam performance by estimating and compensating the nonlinear array shape. A polynomial curve fitting in the least square sense is used to estimate the array shape iteratively with the distributed heading sensors data along the array. Real time array shape estimation and nonlinear array beam calculation is applied to a very long towed line array sensor system and the beam performance is evaluated and compared to the linear beamformer for the simulation and sea trial data.

• The Journal of Engineering Geology
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• v.16 no.1 s.47
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• pp.23-30
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• 2006

This study was carried out to understand the relationship between orientation of tecto-lineaments obtained from aero-photograph and orientation of discontinuities measured at field for the rock types of igneous, sedimentary and metamorphic rocks in Andong area. Total 847 tecto-lineaments were extracted from the aero-photographs and total 1,940 discontinuities including joints, foliations and faults were measured during geologic survey. By using the software DIPS, preferred trends of tecto-lineaments were deduced as N30E-N40E for igneous rocks and N50E-N60E for both sedimentary and metamorphic rocks, while the trends of discontinuities were found as N40E-N50E for igneous rocks, N50E-N80E for sedimentary rocks and N50E-N60E for meta morphic rocks. Even though both orientations for a given rock type showed relatively good agreement in its trend, some discrepancy is also appeared. Since construction safety of geo-structures such as tunnel and slope, etc., is significantly affected by the orientation of discontinuities in rock masses, it is highly recommended to perform a detailed geologic survey as well as an aero-photograph interpretation at a design stage.

• Journal of Korean Medical classics
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• v.18 no.4 s.31
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• pp.15-26
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• 2005

통과연구(通過硏究)${\ulcorner}$의학입문(醫學入門)${\lrcorner}$중대어삼음삼양각자이육기배속원리(中對於三陰三陽各自以六氣配屬原理), 육기납지(六氣納支), 절기방위(節氣方位), 표본음양속성(標本陰陽屬性), 경맥납지(經脈納支), 맥체(脈體), 치법(治法), 중기등진행분류급고찰(中氣等進行分類及考察), 득출결론여하(得出結論如下) : 1. 삼음삼양적속성여지지적배속불일치(三陰三陽的屬性與地支的配屬不一致). 태양화궐음수연이지지여진술화사해(太陽和厥陰雖然以地支與辰戌和巳亥), 인신상배속(寅申相配屬), 단시실제상표본적음양속성여납지적원리시부동적(但是實際上標本的陰陽屬性與納支的原理是不同的). 인차(因此), 재구별표본음양적특성상(在區別標本陰陽的特性上), 절기(節氣), 방위등불능성위일정기준(方位等不能成爲一定基準). 2. 삼음삼양본기적오행속성화경맥납지(三陰三陽本氣的五行屬性和經脈納支), 유가능불일치(有可能不一致). 양명조금지본(陽明操金之本), 불시수양명대장(不是手陽明大腸), 실제상족양명위재시본(實際上足陽明胃才是本), 소양상화지본(少陽相火之本), 역불시수소양삼초(亦不是手少陽三焦), 실제상족소양담재본(實際上足少陽膽才本). 3. 삼음삼양안조종화규율기치법각이(三陰三陽按照從化規律其治法各異). 제일(第一), 표여본적음양속성상반시용반치법(標與本的陰陽屬性相反時用反治法). 소음본열표한(少陰本熱標寒), 태양본한표열(太陽本寒標熱), 차한열부정(且寒熱不定), 고태양열인한용(故太陽熱因寒用), 이소음한인열용(而少陰寒因熱用). 제이(第二), 표여본적음양속성상동시용정치법(標與本的陰陽屬性相同時用正治法). 태음표본균한(太陰標本均寒), 소양표본균열(少陽標本均熱), 고태음한인한용(故太陰寒因寒用), 색인색용(塞因塞用), 이소양통인통용(而少陽通因通用). 제삼(第三), 표여본적음양속성상반(標與本的陰陽屬性相反), 차여중기적음양속성부동시(且與中氣的陰陽屬性不同時), 불능용정치혹반치법(不能用正治或反治法), 응구종어중진행치료(應驅從於中進行治療). 즉불능구니어궐음화양명적소정치법(卽不能拘泥於厥陰和陽明的所定治法), 응수기종중진행치료(應隨機從中進行治療). 4. ‘소음태양(少陰太陽) 종본종표(從本從標)’ 재응용어치료시(在應用於治療時), 가해석여하(可解釋如下): 제일(第一), 혹자종본(或者從本), 혹자종표(或者從標). 제이(第二), 혹자종본(或者從本), 혹자종표(或者從標), 단치료상유기선후지별(但治療上有其先後之別). 제삼(第三), 소음한인열용(少陰寒因熱用). 태양열인한용(太陽熱因寒用), 고동시구종어표본(故同時驅從於標本). 5. 재(在)‘양명궐음(陽明厥陰) 부종표본(不從標本) 종호중(從乎中)’적(的)‘종호중(從乎中)’, 가이해위재치법운용중가이(可理解爲在治法運用中可以)‘수기취중(隨機取中)’지의(之意).

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.9
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• pp.735-738
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• 2018

The accuracy of extracting the azimuth angle of a target is significantly affected by the error in the mono-pulse ratio of the air-borne antenna hybrid mono-pulse Radar system. This error is strongly induced by the phase imbalance between the channels of the system. In this paper, a method is proposed for effectively calibrating the phase imbalance caused by physical differences between the RF channels from the antenna to the $180^{\circ}$ hybrid. Through a flight test, it was confirmed that the accuracy of the azimuth angle of the target is improved by using the proposed method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.6
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• pp.1167-1173
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• 2005

In this paper, the use of an antenna array is considered for code timing acquisition of DS-CDMA signals. The probabilities of acquisition are evaluated by applying multiple narrow fixed-beams to the conventional MUSIC acquisition approach in the multiuser environment on the time-varying Rayleigh fading channel. Each fixed-beam for spatial filtering is dedicated to an individual angular sector that is formed by dividing the entire angular domain by the number of antenna elements. The fixed-beams with a capability of interference suppression provide the additional degrees of freedom,. Hence, the multibeam-based MUSIC estimator can be used to synchronize to more users than the conventional MUSIC algorithm for one antenna. The multibeam-based subspace method is evaluated to significantly improve the performance of a single antenna based MUSIC technique in multiuser scenarios.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.181-184
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• 2016

This study is to compensate for inaccuracies in accordance with the change in the deviation correction value due to the movement and location of the ship cargo, equipment of the vessel, and eliminating the inconvenience of hand. By modifying the deviation through the simplification and automation was planned for accuracy and ease of modification of the modified value. The main method used is charted by measuring 24 direction and inputting the value of magnetic compass direction in automatic deviation-correcting apparatus manually or automaticallyThe measured values are exhibited in Table data and made it possible to calculate accurate correction value deviation. From this it can make deviation table having the margin of error within ${\pm}3^{\circ}$in all regions of the world And this table will help to navigational safety and economy under the unavailable or limited gyro contion.

• Journal of Software Engineering Society
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• v.28 no.1
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• pp.7-12
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• 2019

Recently, as the weight of software in the weapon system increases, the quality of the software becomes a very important factor. In order to improve the quality of the weapon system software, DAPA(Defense Acquisition Program Administration) has institutionalized software reliability in Weapon System Software Development and Management Manual. The manual presents specific methods and procedures to improve the weapon system software quality. In order to meet the required reliability test standards specified in the manual, it is necessary to continuously detect and correct defects throughout the entire development period. However, it is difficult to build proper reliability test environment due to the cost of software reliability tools, setting up secured and separated network environment, and etc. Therefore, in this study, we propose an efficient environment construction method for software reliability test of defense industry field in restricted development environment and limited resources.

• The Journal of the Acoustical Society of Korea
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• v.38 no.3
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• pp.302-307
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• 2019

In modern Anti-Submarine Warfare, there are various ways to locate a submarine in a two-dimensional space. For more effective tracking and attack against a submarine the depth of the target is a critical factor. However, it has been difficult to find out the depth of a submarine until now. In this paper a possible solution to the depth estimation of submarines is proposed utilizing DIFAR (Directional Frequency Analysis and Recording) sonobuoy information such as contact bearings at or prior to CPA (Closest Point of Approach) and the target's Doppler signals. The relative depth of the target is determined by applying the Pythagorean theorem to the slant range and horizontal range between the target and the hydrophone of a DIFAR sonobuoy. The slant range is calculated using the Doppler shift and the target's velocity. the horizontal range can be obtained by applying a simple trigonometric function for two consecutive contact bearings and the travel distance of the target. The simulation results show that the algorithm is subject to an elevation angle, which is determined by the relative depth and horizontal distance between the sonobuoy and target, and that a precise measurement of the Doppler shift is crucial.

• The Journal of the Acoustical Society of Korea
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• v.41 no.2
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• pp.192-198
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• 2022

As an effective weapon system for anti-submarine warfare, DIrectional Frequency Analysis and Recording (DIFAR) sonobuoy detects underwater targets via beamforming with three channels composed of an omni-direcitonal and two directional channels. However, ambient noise degrades the detection performance of DIFAR sonobouy in specific direction (0°, 90°, 180°, 270°). Thus, an ambient noise redcution technique is proposed for performance improvement of acoustic target detection of DIFAR sonobuoy. The proposed method is based on OTA (Order Truncate Average), which is widely used in sonar signal processing area, for ambient noise estimation and Wiener filtering, which is widely used in speech signal processing area, for noise reduction. For evaluation, we compare mean square errors of target bearing estmation results of conventional and proposed methods and we confirmed that the proposed method is effective under 0 dB signal-to-noise ratio.