• 한국광학회지
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• 제11권4호
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• pp.294-298
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• 2000

반도체레이저로 단면 여기시킨 Nd:VAP 레이저의 내부공진기 제2고조파 출력특성을 조사하였다. 유도방출 단면적과 형광수명의 곱이 커 낮은 발진문턱 특성을 갖는 Nd:S-VAP 매질은 컴팩트한 마이크로칩 레이저에 적합하다. 내부공진기를 이용한 제2고조파 발진문턱에너지가 81 uJ로 측정되어 쉽게 발진됨을 확인하였다. 여기에너지 $2\mu\textrm{J}$에서 제2고조파 에너지 $126\mu\textrm{J}$을 얻었고, 내부공진기 제2고조파의 출력을 계산하여 이론적인 해석 근거를 제시하였다. Q-스위치된 제2고조파 출력은 펄스폭 26ns에 펄스당 에너지 $15\mu\textrm{J}$로 저출력에서도 시.공간적으로 깨끗한 펄스를 얻었으며, $M^2$도 1.47로 우수한 빔 특성을 나타내었다.

• 한국세라믹학회지
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• 제47권2호
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• pp.189-194
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• 2010

Compared with organic fluorophores, semiconductor quantum dots (QDs) have the better properties such as photostability, narrow emission spectra coupled to tunable photoluminescent emissions and exceptional resistance to both photo bleaching and chemical degradation. In this work, CdSe/ZnS QDs nanobeads were prepared by the incorporation of CdSe/ZnS QDs with mesoporous silica to use as the optical probe for detecting toxic and bio- materials with high sensitivity, CdSe/ZnS core/shell QDs were synthesized from the precursors such as CdO and zinc stearate with the lower toxicity than pyrotic precursors. The QD-nanobeads were characterized by transmission electron microscopy, FL microscopy, UV-Vis and PL spectroscopy, respectively.

• 정보보호학회논문지
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• 제9권1호
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• pp.47-56
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• 1999

역할기반 접근통제는 사용자의 역할에 기반을 둔 접근통제 방법으로 기존의 임의적 접근통제나 강제적 접근통제에 비하여 다양한 컴퓨터.네트워크 보안분야에 있어서 유연성과 적용성을 제공한다. 본 논문에서는 Ravi S. Sandhu가 최초로 제안한 역할기반 접근통제 기본 모델인 RBAC$_{0}$ 모델에 주체 및 객체의 역할을 추가로 고려하여 확장된 역할기반 접근통제(ERBAC$_{0}$:Extended RBAC$_{0}$) 모델을 새롭게 제안하였다. 제안된 ERBAC$_{0}$ 모델은 기존의 RBAC$_{0}$ 모델에 비하여 주체 및 객체 수준에서의 역할기반 접근통제를 보다 정교하게 제공할 수 있다.

• 한국의류학회지
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• 제47권4호
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• pp.684-695
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• 2023

The Korean Volunteer Corps (KVC) and the Korean Independence Army (KIA) were Korea's main armed forces that led the independence movement against Japan. KVC members were partly merged into the KIA as the army's first branch in 1942. This study examines two different styles of KVC military uniforms: one that complies with the Uniforms Act of the Army of the Chinese Nationalist government and one that uses the same style without a field cap and a belt. The KIA's first branch had three different uniforms: one similar to that of the KVC, one belonging to the KIA and following the Army Uniform Protocol, and one influenced by the U.S. Army. The KVC and the KIA's first branches had insignias representing their identity. The former wore a distinctive insignia with the corps' name, whereas the latter had a cap badge with Korean national symbols under the Army Insignia Protocol. KVC members who may have initially worn their previous uniform in the early days of joining the KIA later adopted the KIA style. This study is expected to offer basic resources to reproduce KVC and KIA military uniforms and verify the authenticity of related artifacts.

• 무역학회지
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• 제47권2호
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• pp.31-46
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• 2022

The purpose of this study is to measure the degree of discrepancies in the bilateral trade data between South Korea and its five major trade partners and to identify the key factors causing the discrepancies. By analyzing statistics based on the CIF/FOB ratio estimation and taking into consideration the trade flow via Hong Kong, the study finds that the discrepancies in South Korea's trade data with the US, Vietnam, and Japan are insignificant. In case of Hong Kong, however, the value of South Korea's import from Hong Kong is extensively inconsistent with Hong Kong's export to South Korea(i.e. the mirror data) while the value of South Korea's export to Hong Kong generally corresponds to its mirror data. Such discrepancies are caused by differences in recording re-exports, which are often found in the trade flow via entrepôt economics including Hong Kong. Meanwhile, discrepancies in reported bilateral trade flows between South Korea and People's Republic of China(PRC) remain relatively marginal. The discrepancy of statistics between South Korea as the exporter and PRC as the importer is mainly caused by the trade flow via Hong Kong. On the other hand, the discrepancy of statistics between South Korea as the importer and PRC as the exporter is assumably due to the differences in attribution of trade partners.

• 한국항공우주학회지
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• 제46권4호
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• pp.297-305
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• 2018

UCAV는 적진 중심으로의 침투, 공격 등 적대적 상황에서 임무를 수행하는 것을 목표로 한다. 일차적으로 적의 레이더에 포착되지 않아야 하므로 RF 스텔스 기술의 적용이 필수적이다. 최신 RCS 저감 기술이 적용된 대표적인 비행체로는 Blended Wing Body 형태의 X-47B UCAV이다. 본 연구에서는 X-47B와 유사한 모델 UCAV 형상을 설계한 다음, Ray Launching Geometrical Optics(RL-GO) 기법을 활용하여 모델 UCAV의 고주파수 영역에서의 RCS 특성을 분석하였다. 특히 IR 저감이 고려된 UCAV 형상이 RCS에 미치는 영향성을 조사하였다. 마지막으로 모델 UCAV의 공기 흡입구에 최적화된 RAM을 적용하였을 때의 RCS 변화를 분석하였다.

• 한국양식학회지
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• 제9권2호
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• pp.179-186
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• 1996

실험실에서 부화시킨 도화새우의 zoea 유생발달에 따른 섭식, 성장, 탈피 및 대사에 관한 에너지수지를 분석하였다. 도화새우의 zoea 전 유생기간중 섭식에 의한 총에너지는 140.88 J이었다. 이중 체성장에 사용된 에너지는 17.07 J이었고 호흡, 탈피 및 배설에 사용된 에너지는 각각 16.22 J, 1.19 J 및 106.40 J이었다. 섭식한 먹이에 대한 동화효율(assimilation efficiency, A/I)은 $24.47\%$였다. 성장으로 전환된 에너지의 총섭식에너지에 대한 백분률인 총성장효율(gross growth efficiency, $K_1$)과 성장으로 전환된 동화에너지에 대한 백분률인 순성장효을 (net growth efficiency, $K_2$)은 각각 $12.96\%$와 $52.96\%$ 였다. 동화에너지가 체성장과 대사에너지에 사용된 것은 각각 $49.51\%$와 $47.04\%$였다.

• 한국작물학회지
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• 제32권4호
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• pp.462-465
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• 1987

서광벼/밀양5004, HR 1619-6-2-1-2-2 /밀양5004 및 55061/IR 19735-5-2-3-2-1등 3개 조합의 F$_1$ 잡종과 이들 양친품종들의 혼묘를 각각 도열병 race IA-61, IB-47, IC-13 및 IH-1 등의 단독 race와 IC-13과 IA-61, IC-13과 IB-47 및 IC-13과 IH-1 등 2 race씩의 혼합 inoculum으로 접종시켜 이들의 잎도열병 발병반을을 검토하였다. 3개 조합의 양친품종들은 단독 race에 대해서 서로 다른 반응을 보여 각각 서로 다른 저항성 유전자의 지배를 받는 것으로 나타났다. 이들 서로 다른 정항성 유진자를 가진 양친품종들은 반응이 다른 2 race 씩의 혼합 inoculum에 대해서 모두 이병성이었으나 이들간의 F$_1$ 잡종은 모두 저항성이었다. 저항성 유전자가 서로 다른 양친품종간의 F$_1$ 잡종은 저항성 유전자의 집적효과로 인해 양친보다 광범한한 저항성을 나타내었다.

• 가정과삶의질연구
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• 제8권1호
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• pp.83-100
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• 1990

The purposes of the study are to understand of rural family life cycle(FLC) and to get a FLC model for the twentieth in rural area. Data for the study were collected from 603 farm households in rural area. The major findings are as follows; 1) The age of first marriage was 21.5 years old(urban : 22.4), the first bearing 23.2(24.2), the last bearing 31.7(32.6), the first child marriage 47.2(46.5), and the last child marriage 59.7(52.7). The number of child and interval were 3.9 persons and 2.9 years respectively. From the survey results, the rural family life cycle was established. Establishment stage(from the marriage to the 1st child birth) : 21-23 yrs. Extension stage(from the 1st child birth to the last child birth) : 23-32 yrs. Complete extension stage(from the last child birth to the 1st child's marriage) : 32-47 yrs. Shrinking stage(from the 1st child's marriage to the last child's marriage) : 47-60 yrs. Complete shrinking stage(from the last child's marri ge to the death of husband) : 60-63 yrs. Dissolution stage(from the death of husband to the death of wife) : 53-75 yrs. 2) In general, the older the age, the younger the first marriage age, the greater the number of child, and the longer the interval of child bearing. The last child's marriage was too last to have the period of recovery stage. In terms of FLC by marital chorts, the later the year of marriage, the older the age of the first marriage and first baby bearing, the smaller the number of child, and the faster the launching stage. The higher the educational level, the older age of the first marriage and the first baby bering, the smaller the number of child, and the shorter the interval of child bearing. 3) Two types of rural FLC model for the twentieth were formulated. Type A was formulated based on the survey results and type B was formulated based on 『'88 population dynamics survey』 of Economic Planning Board(EPB). 「TYPE A」*Establishment stage(from the marriag to the 1st child birth) : 22.5-23.5 yrs. one child : the 1st child's marriage(49.5yrs), the death of husband(64.2yrs), the death of wife(71.7yrs) two children : the last child's birth(25.7yrs), the last child's marriage(51.7 yrs) three children : the last child's birth(27.9yrs) the last child's marriage(53.9yrs) 「TYPE B」*Establishment stage(from the marriage to the 1st child birth) : 25.3-26.3 yrs. one child : the lst child's marriage(52.3yrs), the death of husband(67.0yrs), the death of wife(74.5yrs) two children : the last child's birth(27.8yrs), the last child's marriage(53.8 yrs.) three children : the last child's birth(29.3yrs), the last child's marriage(55.3yrs).

• ETRI Journal
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• 제9권2호
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• pp.36-47
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• 1987

We have developed three types of muldexes; they are 140Mbit/s muldex, 565Mbit/s muldex and monitor & control muldex for a 565Mbit/s optical fiber transmission system. The frame format of our own type has been constructed for the M&C muldex, and new direct and parallel reframe techniques have been invented for 140Mbit/s, and 565Mbit/s muldex. Their functions, configurations and perform ance evaluations are described here.