• 대한기계학회논문집A
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• 제38권2호
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• pp.219-225
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• 2014

폰 카메라용 렌즈모듈을 구성하는 각 단렌즈의 방향성을 고려한 자동 조합시스템을 개발하였다. 먼저 유동해석을 통하여 렌즈모듈의 조합성 도출 영향인자인 복굴절과 사출성형 조건의 상관성 및 조립 방향성에 따른 수율의 관계를 조사 하였다. 하나의 조립모듈에서 렌즈와 스페이서의 한 세트를 조립하도록 설계하여 생산성 향상 및 장비크기를 최소화하여 기존 장비의 약 25 %정도로 축소가 가능하였다. 또한, 기구적인 정렬기구인 센터링 기구 및 배럴가이드 적용하여 추가적인 비전시스템 없이 사이클 타임의 단축이 가능하였다. 개발한 시스템은 모듈러 설계를 통하여 픽커 및 가이드 등 일부 부품만의 교체로 생산모듈 변경에 대응 가능하도록 하여 급변하는 시장변화 및 소량생산에도 적용 가능하도록 제작되었다.

• Journal of Advanced Marine Engineering and Technology
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• 제40권9호
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• pp.799-804
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• 2016

광대역 전력선 통신은 전류의 흐름과 함께 효과적인 양방향 통신을 얻기 위하여 전력선 분배망을 통신 매체로 이용한다. 그러나 전력선은 통신에 최적화된 채널이 아니므로 인터넷, 음성 및 데이터 서비스에 대한 통신 시스템의 개발은 시뮬레이션에 의한 성능 분석에 적합한 측정 기반의 전송 모델을 필요로 한다. 본 논문에서는 복잡한 전달 함수를 기술하는 분석 모델을 다중 전력선 모델의 감쇠 및 경로 파라미터를 획득하는데 이용하였으며 이를 바탕으로 주파수 응답특성을 계산하였다. 계산된 결과는 다중경로에 의한 주파수 선택성 페이딩과 주파수에 대한 신호의 감쇄를 보여주었으며 이는 실험 결과와 잘 일치하였다. 이론모델에 적용한 배전선을 실험적으로 구성한 후 배전선에 전기적인 신호를 인가하는 방법으로 비접촉식 결합을 위한 페라이트 코어로 구성된 유도 결합 장치를 사용하였다. 신호 결합 손실은 커플러에 감긴 권선수에 의해 최소화 될 수 있다. 3회 권선 결합 효율은 일회 권선 결과보다 6dB 이상 개선됨을 보였다.

• 산업경영시스템학회지
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• 제39권2호
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• pp.64-71
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• 2016

Recently, nanotechnology has grown as one of the leading science technology along with other converging technologies such as biology, information, medicine etc., bringing the continuous investment of the government in nano-related field. However, it is difficult to measure and evaluate the performance of the national research and development programs because of the multidimensional character of the expected outcomes. This study aims to measuring efficiency of the national nanotechnology research and development programs using DEA model. The decision making units are nine nano-related ministries including the Ministry of Science, ICT and Future Planning. The input variables are total expenditure, number of the programs and average expenditure per program. The output variables are science, technology and economic indicator, and the combination of these outputs are respectively measured as seven different DEA cases. The Ministry of Science, ICT and Future was the first efficient ministry in total technical efficiency. Ministry of Agriculture, Food and Rural Affairs and the Ministry of Food and Drug Safety were efficient in pure technical efficiency, when the Ministry of Commerce Industry and Energy took the first in the scale efficiency. The program efficiency was affected by organizational characteristics such as the institution's scale, the concentration of the research paper or the patent, technology transfer or the commercialization. The result of this study could be utilized in development of the policy in the nanotechnology and the related field. Furthermore, it could be applied for the modification of expenditure management or the adjustment of the research and development programs' input and output scale for each ministry.

• 한국가금학회지
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• 제39권1호
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• pp.27-32
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• 2012

This experiment was conducted to investigate the dietary effects of turmeric powder (TP) on laying performances, egg qualities and its transfer into eggs. A total of two hundred, 60-wk-old, Lohmann Brown layers were divided into 4 groups, placed in to 5 replicates per group (10 layers each) and fed each one of four diets containing 0% TP (control), 0.10, 0.25 or 0.50% TP, respectively, for 7 wks. Egg production in the all groups fed diets containing TP were significantly higher than that in control (P<0.05). No differences in feed intakes, egg and eggshell qualities were observed among the treatments, but Roche color fan number (yolk color) in group fed diet with 0.5% TP was significantly higher than in control (P<0.05). In the groups fed diets containing TP, Haugh units after 2 wk of storage were significantly higher than that of control (P<0.05). The curcumin content of egg yolk in the groups fed diet containing 0.50% TP was significantly higher than those in the other groups (P<0.05). The cholesterol levels of egg yolk were not influenced by dietary TP. It was concluded that dietary TP was effective in improving laying performance and internal egg qualities. TP can be also used as a feed additive for the production of value-enhanced eggs with increased yolk color and curcumin content.

• 한국초지조사료학회지
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• 제12권3호
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• pp.30-40
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• 1992

The area of grassland established and the arable land in forage production have been decreased recently in Korea. As a result, forages available from the grassland and the arable land provided only 40% of the total roughage consumed by cattle in 1991, compared with 54% in 1989. The decreasing trend of the forage production has been impinged on by a number of legislative. socio-economic. technical and other constraints negatively affecting grassland and forage development. Consequently. effective systems and strategies are quite necessary to have sustainable grassland farming in Korea. In spring and autumn, temperatures are too low for subtropical forage crops, and the summer monsoon climate is another serious limitation to the use of cool-season species. Therefore it is an imperative that not only the research-based grassland development but also the forage crop production should be strongly supported by the government authorities to overcome such climatic limitations. Private forest land holdings are of relatively small units in Korea. Accordingly. it is necessary and important to enlarge the forest land holdings per farm to develop as economic units of grassland. For this the government should introduce new policy measures such as for example: long-term leases of Sorest land and the idle arable land of absentee owners ; rational rental system of national and public forest lands; integrating livestock and forest production. All the laws and regulations standing in the way of the grassland development in forest lands should be modified and revised to open the way for much easier development of grassland. It is also proposed that a high level of financial incentives -hould be provided for structural improvements for the grassland development. They may be: mechanization facilitation, construction of new roads relating to grassland, and land exchange and consolidation. And it is basically necessary that financial enumeration or profits must be garanteed in order to motivate farmers to keep up farming continuously. For more efficient grassland development in mountainous areas, reorganization of Alpine Experiment Station and NAB1 Namwon Branch Station may be needed. Research should be strengthened for completion of pasture mixtures, development of maximum forage production methods with a view to saving labor and reducing production costs, introduction of grazing and forage conservation techniques. and utilization of rice straw as more palatable and nutritious forage source. In order to have more efficient and effective transfer of advanced forage production technologies to livestock farmers the user-clients. it is also essential that special training measures should be given to livestock farmers through making greater use of specialized research and extension workers.

• 대한기계학회논문집B
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• 제38권11호
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• pp.925-933
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• 2014

오늘날 고성능컴퓨터로 인해 많은 산업분야에서 전산해석이 사용되고 있다. 하지만 정해진 컴퓨터자원과 시간에 의해 3 차원 풀 스케일 해석에서는 많은 어려움 등이 있다. 본 연구에서 ${\varepsilon}-NTU$ 식과 열교환기 성능의 데이터베이스를 이용해 열교환기의 성능예측프로그램을 개발하였다. 다양한 타입의 열교환기 형상정보와 성능데이터베이스를 구축하였고, 이를 바탕으로 정해진 작동 조건에서 열교환기의 성능을 계산하였다. 계산된 정보를 바탕으로 최적의 사이즈를 갖는 형상을 찾기 위해 유전알고리즘(Genetic Algorithm)을 이용하였다. 계산을 위해 상용 소프트웨어인 MATLAB 과 REFPROP 이 사용되었다.

• 한국컴퓨터정보학회논문지
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• 제16권5호
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• pp.41-50
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• 2011

본 연구에서는 안드로이드 플랫폼 기반에서 영어 프리젠테이션 학습을 위한 모바일 콘텐츠 제작 및 모바일 학습시스템을 개발하였다. 첫째, 안드로이드 플랫폼에서 영어 학습용 콘텐츠를 구동할 수 있게 해주는 콘텐츠 전송시스템을 포함하는 어플리케이션의 개발하였다. 본 연구에서 개발한 어플리케이션은 언어 선택, 학습 모드 선택, 재생, 퀴즈, 사전, 정지 또는 일지정지 그리고 이전 또는 다음 화면으로 이동하는 기능을 제공한다. 둘째, 영어 프리젠테이션 학습을 위한 콘텐츠의 제작하였다. 영어 프리젠테이션 학습을 위한 콘텐츠는 크게 2개의 part(기본 파트 그리고 고급 파트)로 구성되며, Part 1과 Part 2 각각은 9개의 unit 으로 구성되어 총 18개 unit으로 구성되고, 각 unit 별 2-5개의 chapter로 구성되어 총 51개의 chapter로 구성되었다. 본 연구에서 개발한 시스템을 사용해보도록 한 후 사용자가 인지하는 사용자 인터페이스(UI) 만족도와 학습 만족도를 평가를 실시하였다. UI 만족도에 대한 설문 분석 결과, 응답자의 85%가 보통 수준 이상 만족하는 것으로 나타났으며, 학습 만족도에 대한 설문 분석결과, 응답자의 95%가 보통 수준 이상으로 만족하는 것으로 나타났다.

• 한국언어정보학회지:언어와정보
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• 제9권2호
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• pp.49-68
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• 2005

Application of chunking to English and some other European languages has shown that it is a viable parsing mechanism for natural languages. Although a small number of attempts have been made to apply chunking to the analysis of the Korean language, it still is not clear enough what criteria there are to identify appropriate units of chunking, and how efficient and valid the chunking algorithms would be when applied to some authentic Korean texts. The purpose of this research is to provide an alternative set of algorithms for chunking Korean, and to implement them, and to test them against some English-Korean parallel corpora, which is English and Korean bibles matched sentence by sentence. It is shown in the paper that aligning related texts and identifying matched phrases between the two languages can be achieved through appropriate chunking and matching algorithms defined on the morphologically-tagged parallel corpus. Chunking and matching processes are based on the content words rather than the function words, and the matching itself is done in terms of the transfer dictionary. The implementation is done in C and XML, and can be accessed through the Internet.

• 대한화학회지
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• 제26권6호
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• pp.421-426
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• 1982

자유 라디칼 개시제에 의한 인산디에틸이소프로페닐(DEIPA)과 초산비닐(VAc) 및 아크릴로니트릴(An)의 혼성중합 연구를 행하여 단위체 반응성비를 얻었다. 개시제로는 과산화벤조일을 사용하였으며 중합온도는 $60^{\cric}C$이었다. 단위체 반응성비는${\gamma}_1$(VAc) = 1.56, ${\gamma}_2$(DEIPA) = 0.44: ${\gamma}_1$(AN) = 15.2, ${\gamma}_2$(DEIPA) = 0.031이었다. 이 값으로부터 DEIPA의 Alfrey-Price 상수 Q=0.015, e=0.39 및 Q=0.014, e=0.34를 얻었으며${\alpha}$ 위치에 있는 메틸기가 반응성을 감소시킴을 알았다. 공중합체중 DEIPA의 함량이 증가함에 따라 공중합체의 고유점성도 및 수평균 분자량이 감소함도 알았다.

• 임상간호연구
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• 제18권3호
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• pp.354-367
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• 2012

Purpose: This study was done to verify validity and reliability of a neonatal patient classification system (NeoPCS-1). Methods: An expert group of 8 nurse managers and 40 nurses from 8 Neonatal Intensive Care Units in Korea, verified content validity of the measurement using item level content validity index (I-CVI). The participants were nurses caring for 469 neonates. Data were collected from November 11 to December 14, 2011 and analyzed using descriptive statistics, ANOVA, intraclass correlation coefficient, and K-cluster analysis with PASW 18.0 program. Results: Nursing domains and activities included 8 items with 91 activities. I-CVI was above .80 in all areas. Interrater reliability was significant between two raters (r=.95, p<.001). Classification scores for participants according to patient types and nurses' intuition were significantly higher for the following patients; gestational age (${\leq}29$ weeks), body weight (<1,000 gm), and transfer from hospital. Six groups were classified using cluster analysis method based on nursing needs. Patient classification scores were significantly different for the groups. Conclusion: These results show adequate validity and reliability for the NeoPCS-1 based on nursing needs. Study is needed to refine the measurement and develop index scores to estimate number of nurses needed for adequate neonatal care.