• 한국광학회지
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• 제6권1호
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• pp.1-7
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• 1995

열상장비용 줌망원경계통을 설계하였다. 대물경계는 4배로부터 14배까지 배율이 변화할 수 있는 줌광학계통으로 설계하였고 접안경은 초점거리 25mm의 삼중렌즈계통으로 설계하였다. 처음에는 대물경계와 접안경을 구분하여 설계하고 후에 이를 통합하여 무초점계로 설계하였다. 1st order optics에 의해 계통을 확립하고 3rd order optics에 의해 초기설계를 얻었으며 후에 유한광선추적으로 모든 고차수차를 포함하는 ray aberration 또는 angular aberration이 최소가 되도록 최적화 하였다. 최종설계를 회절광학적 MTF를 계산하여 성능을 평가하였다.

• 한국추진공학회지
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• 제8권4호
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• pp.26-35
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• 2004

터보펌프 공급방식 액체추진제 로켓엔진시스템의 추력제어기술 연구의 일환으로 터보펌프의 저주파 동특성에 대한 연구가 진행되었다. 터보펌프는 1차 지연요소를 가지는 시스템이며, 회전수 변화에 대하여 펌프의 모멘트 변화와 터빈의 모멘트 변화의 차가 양일 때 1차 지연요소의 시정수는 양의 값을 가지게 되고, 따라서 시스템은 안정하였다. 또한 이 값이 양의 큰 값을 가질수록 응답성은 향상되었으며, 제어성은 감소하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.301-306
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• 2000

Small passenger and car carrier ships are mainly used as a connection way between land and small islands. And these ships should be designed to enlarge the capacity of passenger and car loading within limited space and draft. So the resonances of various vibrations exist in normal operation range of engine and propulsion shafting. In this paper, hull's superstructure vibration which was especially induced by the 1st order excitation of whirling vibration on the 2-engines and 2-propulsion shafting systems is introduced. Also these are verified via the theoretical analysis using transfer matrix method and FEA software ANSYS and its vibration measurement.

• 한국군사과학기술학회지
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• 제24권2호
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• pp.187-196
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• 2021

The Network-Centric warfare over weapon data link networks has been developed for the recent decade. Since the US navy had begun to develop tactical digital information chain, it has gradually transformed into weapon data link technology. As data link network system and its protocol have been advanced into high-technology, focusing and targeting on moving targets become possible in net-enabled environments. However, it is difficult to identify the primary information from numerous battlefields and understanding approaches to damage a target in a timely manner. In this paper, to better understand the targeting assessment, we suggest a specific solution: Bomb Hit Indication(BHI) using information in weapon data link messages. In order to prove our suggestion, we implement the BHI solution and apply it into the weapon data link integrating system.

• 한국전기전자재료학회논문지
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• 제18권1호
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• pp.43-49
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• 2005

Temperature stabilities of resonance frequencies of the substrates are very important in piezoelectric ceramics oscillators and fitters. In this study, it was investigated thermal resisting property of the length-extensional vibration mode of PZT ceramics. The mode can be utilized in fabricating ultra-small 55 kHz IF devices. We fabricated the ceramic specimens with x = 0.51, 0.52, 0.53, 0.54, and 0.55 in the Pb(Zr$\sub$x/Ti$\sub$1-x/)O$_3$ system. And their resonance frequencies were measured before 1st thermal aging, after 1st and 2nd thermal aging. In order to investigate the influence of thermal aging on thermal resisting properties, thermally aged specimens were once mote thermally aged. Before 1st thermal aging, the specimens of the compositions with morphotropic phase, x = 0.53 and rhombohedral phase, x = 0.54 have weak thermal resisting property of resonance frequency, while tetragonal phase, x = 0.51 has robust thermal resisting property of resonance frequency. 1st thermal aging improved thermal resisting property of resonance frequency in all specimens.

• 한국멀티미디어학회논문지
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• 제22권7호
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• pp.815-821
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• 2019

This paper presents the design and implementation of a Mission Planning System(MPS) for multiple ballistic missiles. MPSs are also a kind of M&S systems in defense domain, and these provide important computations on the ground before flights of flying objects. The proposed MPS in this paper has a new concept which is far from generating a set of waypoints of a flying object and proving the set. In this paper, we firstly discuss the research motivation of our own MPS; then, we introduce the design of our MPS and its functionalities. In order to prove the practicality of our MPS, we have conducted a case study.

• 한국공간구조학회논문집
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• 제19권1호
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• pp.53-64
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• 2019

The objective of this study is to investigate the earthquake response for the design of 100m spanned single-layer lattice dome. The plastic hinge analysis and eigenvalue buckling analysis are performed to estimate the ultimate load of single-layered lattice domes under vertical loads. In order to ensure the stability of lattice domes, it is investigated for the plastic hinge progressive status by the pushover increment analysis considering the elasto-plastic connection. One of the most effective methods to reduce the earthquake response of large span domes is to install the LRB isolation system of a dome. The authors discuss the reducing effect for the earthquake dynamic response of 100m spanned single-layered lattice domes. The LRB seismic isolation system can greatly reduce the dynamic response of lattice domes for the horizontal and vertical earthquake ground motion.

• 한국환경보건학회지
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• 제19권4호
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• pp.14-24
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• 1993

The present study was accomplished from October, 1992 to June, 1993 in order to examine the seasonal community structure of aquatic insects and the biological estimation of water quality by the aquatic insects of the Jungneung and Gokneung streams in the Mt. Bukhan. The obtained results are as follows: 1. The total taxa of aquatic insects appeared as 77 species, 45 genera, 28 families in 7 orders. 2. Seasonal occurrence species numbers showed the highest in the autumn of the Jungneung stream (19 species) and in the spring of the Gokneung stream (41 species). Seasonal occurrence individual numbers showed the highest in the summer of the Jungneung and Gokneung streams (5,901, 3,180 individuals) and the lowest in the autumn of Jungneung stream (612 individuals) and in the winter of the Gokneung stream (1,764 individuals). 3. Annual dominance indices showed 0.52 (stJ1)~1.00 (st.J3) range in the Jungneung stream, and 0.47 (st. G1)~0.76 (G2) range in the Gokneung stream. 4. Seasonal species diversity indices showed 0.00 (st J3, whole seasons)~3.12 (st.J1, Spring) range in the Jungneung stream and 0.69 (st. G2, summer) ~3.10 (st. G4, spring) in the Gokneung stream. 5. Biological saprobic system based on species diversity indices of aquatic insects appeared as oligosaprobic area: site J3, $\alpha$-mesosaprobic area: site J2, G2, G3 and $\beta$-mesosaprobic area: site J1, G1, G4.

• 공업화학
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• 제8권3호
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• pp.347-356
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• 1997

스티렌(St)과 n-부틸메타크릴레이트(n-BMA)를 용매인 톨루엔에서 과산화벤조일(BPO)를 개시제로 사용하여 $80^{\circ}C$에서 연속반응기를 사용하여 용액공중합을 행하였다. 반응물 부피, 체류시간은 각각 0.6L, 3시간으로 하였다. 단량체 반응성비 $r_1$(St)과 $r_2$(BMA)는 Kelen-Tudos방법 (또는 Fineman-Ross방법)으로 결정하였다. : $r_1$=0.75(0.67), $r_2$=0.61(0.56). 공중합체의 가교정지인자, $\phi$값은 스티렌의 전체 조송에 대해 0.44~0.78값을 가지고 공중합체내 스티렌 조송이 증가할수록 $\phi$값도 증가하고 있다. 스티렌과 부틸메타크릴레이트의 공중합반응은 2차 반응속도식에 따랐으며 시뮬레이션한 전환율과 공중합 속도를 실험결과와 비교하였다. 동족인 정상상태에 도달하는 평균시간은 체류시간의 3.5배였다.

• 한국군사과학기술학회지
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• 제17권4호
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• pp.404-412
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• 2014

We proposed a design method for squib current supply & interlock circuits in guided-missile fire control systems. In order to design squib current supply circuits, various missile squib loads including line resistance and squib devices have to be considered in advance minimizing probability of redesign of circuits and reducing the development cost by implementing the most proper squib current supply circuit. Also, we presented a hardware interlock logic instead of the commonly used software safety logic to improve the safety of guided-missile fire control systems. The proposed squib interlock circuit enhances safety requirements of guided-missile fire control systems. We confirmed that simulation and measurement results of the proposed design method are the same as theoretical analysis results.