• KDI Journal of Economic Policy
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• v.27 no.2
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• pp.89-121
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• 2005

This paper investigates the empirical relationship between investment and uncertainty using the firm level data of Korean manufacturing sector. Empirical results show that uncertainty is negatively correlated with investment only for the post-crisis sample period. In particular, the negative effect of uncertainty on investment is more significant for low interest coverage ratio firms, high debt-asset ratio firms and small firms. The results are consistent with the claim that firms act in a more risk-averse manner after the financial crisis. This paper also finds a significant sensitivity of investment to cash flows only for the pre-crisis sample period, suggesting that financial constraint is not relatively important in explaining low investment after the financial crisis.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.1
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• pp.55-62
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• 2020

It is necessary to develop digital flight control system by digital control technology to ensure stability and maneuverability of rotary helicopter. It is important to meet functional requirements of helicopter flight control system OFP and verify system reliability directly linked to flight safety as a core technology that avoids the transfer of technology by overseas advanced helicopter manufacturer. In this paper, we studied how to perform FMET for operational flight program of rotary automatic flight control system.

• The Journal of Korean Association of Computer Education
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• v.6 no.3
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• pp.207-216
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• 2003

An instructor in education generally takes the objective-type evaluation for grading. The subjective-type evaluation has the merit that it can estimate the high-recognition ability, but the problem of the objectivity and reliability of the evaluation. This paper proposes the model which grades for the subjective-type evaluation. and designs and implements the evaluation system using the synonym thesaurus. This system can process the diverse and wide subjective-type questions and provide the easy usage for a beginner. It also can reduce the time and endeavor for evaluation and provide the objectivity of the evaluation. The system results the 73% success rate. We expect that this system will become a basis of the research on the subjective-type evaluation.

• The Korean Journal of Pesticide Science
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• v.4 no.2
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• pp.56-62
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• 2000

Effects of sublethal dose of imidacloprid on biological characteristics, such as longevity, fecundity and excretions from brown planthopper (BPH) and its repellency to imidacloprid were examined. Topical application of imidacloprid to BPH at the dose of $LD_{10}$ and $LD_{30}$ (These values were determined at 48 hours after topical application of imidacloprid) was remarkably increased the mortality from 3 days after application and showed over 90% mortality on 4 days after application. Topical application of imidacloprid at dose of $LD_{10}$ (16 days) showed no difference compared to the control (16.9 days) in the longevity, while application of $LD_{30}$ was reduced the longevity of BPH to 13.5 days. Application of sublethal dose of imidacloprid to BPH adults reduced the number of eggs laid per day and for adult stage, and the hatchability of their eggs. By root zone application at the dose of $LC_{30}$, 50% longevity and 40% fecundity was reduced respectively, but showed no effect on number of eggs laid per day. The day on which BPH laid 50 % of eggs in number were 7.6 days at the $LC_{10}$ and 5.9 days the of $LC_{30}$ respectively. Hatchabilities of the groups treated with imidacloprid were lower than that of the control. Topical application to BPH at the dose of $LD_{10}$ did not reduce the amount of excretes, but application at the dose of $LD_{30}$ was reduced 26.5% of excretion compared to the control. Leaf dipping into the solution of concentration of $LC_{10}$ and $LC_{30}$ was reduced 96.4% and 98.0% of excretion, respectively. And root zone treatment at the concentration of $LC_{10}$ and $LC_{30}$ reduced 79.5% and 96.6% of excretion, respectively. Repellency rates of BPH to imidacloprid were 20% regardless of the dose of application.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.9-19
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• 2001

This study was carried out to investigate natural insectifuge materials from tree extractives in order to substitute for organic synthetic insecticides for food wrapping corrugated board. Tree samples were collected, extracted, fractionated with hexane, $CH_2Cl_2$, ethylacetate(EtOAc) and $H_2O$, and then freezed dried for further study. EtOAc or $H_2O$ fractions were chromatographed on a Sephadex LH-20 column for isolation and purification, and the isolated compounds were characterized by spectroscopic tools such as NMR and MS. Crude extractives of EtOAc and $H_2O$ fractions were added to the printing ink for corrugated board with the concentration of 2% or 3% based on the weight of the ink, then the prepared ink was printed on the corrugated board to be used for evasion test using larva of indian meal moth(Plodia interpunctella(Hubner)). Robtin, dihydrorobinetin and leucorobinetinidin were isolated from the wood extractives of black locust(Robinia pseudoacacia) and the bark of poplar(Populus alba $\times$ glandulosa) contained many kinds of compounds such as (+)-catechin, naringenin, aromadendrin, eriodictyol, sakuranetin and its glycoside, taxifolin, neosaturanin, salireposide, p-coumaric acid and aesculin. Much of (+)-catechin was isolated from the bark extractives of willow(Salix koreensis) in addition to (+)-gallocatechin and p-coumaric acid and the bark of weeping willow(Salix babylonica) also contained (+)-catechin, (+)-gallocatechin, dihydromyricetin and myricetin.

• Transactions of Materials Processing
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• v.23 no.2
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• pp.110-115
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• 2014

Low cycle fatigue characteristics are very important in the development of automobile suspension parts. Fatigue properties using the strain life approach are usually obtained from low cycle fatigue tests. However, low cycle fatigue testing requires a lot of time and cost. In the current study, an attempt to estimate low cycle fatigue properties of high strength steel sheet from tensile test and tensile simulations is performed. In addition, low cycle fatigue testing was conducted to compare the fatigue properties obtained from tensile testing and simulations. In conclusion, the results effectively predict the low cycle fatigue properties. However, some deviations still exist.

• 한국경영정보학회:학술대회논문집
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• 2007.06a
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• pp.991-993
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• 2007

충북지역의 C대학은 국립대 최초로 경영정보학과를 개설하여 20년 동안 관련 분야의 인재를 양성해 왔다. 하지만, 최근 학부제로 통합되어 운영되고, 기술기피 현상에 따른 전공 지원인력이 감소하고, 정보기술의 보편화로 경영정보의 정체성이 모호해지며, 국내외 경영교육 인증 실시로 인해 교과과정 재검토의 필요성이 제기되고, 지역 관련 업체에 진출하는 졸업생 수가 감소하게 되어 중장기적인 관점에서 학부과정 교과과정의 재검토를 실시하게 되었다. 관련 분야 실무종사자들을 대상으로 경영정보 분야의 지식수요를 파악하고, 재학생/졸업생 대상으로 교육서비스의 만족도를 분석하고, 국내외 전문가를 대상으로 자문을 받고, 경영교육 인증 관련 규정을 검토하는 등의 업무를 수행하여 교과과정 개편 기본방향을 설정하고, 교과과정과 교과운영방향을 제작하는 것을 목표로 작업을 수행하고 있다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.04a
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• pp.64-69
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• 2003

노동 집약적이던 농업은 급속한 기계화로 인하여 노동력의 절감은 여러 분야에서 활성화되고 있지만, 농업은 수익성이 높지 않아 여전히 사람들이 노동을 기피하는 산업중의 하나이다. 온실 자동화는 특용 작물 등의 고부가가치 상품에만 한정되어 있으므로 이를 개선해야 한다. (중략)

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2002.04a
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• pp.25-26
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• 2002

가스터빈 엔진의 성능모사는 개발단계에서의 개발위험도 감소나 개발비용 절감의 목적뿐만 아니라 운용단계에서 최적의 정비를 위한 엔진의 상태 진단을 위해서도 그 필요성이 매우 크다. 가스터빈 엔진의 성능모사를 위해서는 "각 구성품의 성능은 구성품 성능선도를 따라야 한다"는 제약조건을 만족해야 하며 이를 위해서는 구성품의 특성을 나타내는 성능선도가 매우 중요하다. 구성품 성능선도는 다양한 조건에서의 성능시험을 통해 얻는 것이 당연하나 이는 엔진 개발사에서나 가능하며 대부분 공개를 기피한다. 따라서 일반 구매자나 가스터빈 엔진의 성능을 연구하는 사람들은 일부 공개된 성능도를 축척하여 이용하고 있다.여 이용하고 있다.

• 기계와재료
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• v.23 no.1
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• pp.6-13
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• 2011

우리나라는 2000년에 고령화 사회에 공식적으로 진입하였으며 고령화는 더욱 가속화될 전망이다. 노인의 경우 신체적, 인지 및 심리적, 사회적 기능이 저하되어 올바른 사회활동을 하기가 어려울 뿐만 아니라 특성상 새로운 활동을 기피하고 쉽게 지루해 하며 소극적인 성격으로 인해 운동참여 유도가 어렵다. 노인의 건강 증진을 위해 운동 실천률을 높이는 것이 필요하며 쉽게 접근할 수 있고 상해의 위험성이 적은 환경이 제공되어야 한다. 가상현실을 기반으로 한 스포메디 융복합 기술은 스포츠를 가상현실로 구현하여 의료적 효과를 극대화 할 수 있는 기술로써 사용자의 흥미를 유발하고 운동 및 치료의 효과를 동시에 가능하게 하는 기술이다. 본 논문에서는 노인의 특징을 분석하여 가상현실 스포메디 융복합 기술이 갖춰야할 특성에 대해 제시하고, 관련 개발 기술의 연구 및 개발 동향과 스포메디 관련 시장 동향 및 정부 정책 방향에 대해서 분석하였다.