• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.79-82
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• 2003

스위치 박스는 건축물의 전선관용으로 사용되는 금속제 박스이다. 이 박스를 제조할 때는 제 1차 프레스에서 성형을 하고, 제 2차～5차 프레스로 박스의 4측면 가공을 하게 되므로 프레스 4대, 금형 4벌, 작업자 4명을 필요로 한다. 이 때문에 기계 사용료와 금형비, 인건비 둥 제조원가의 상승 요인이 되고 있으며 특히 프레스의 굉음과 진동 및 안전사고의 위험성 등으로 작업자들이 직무를 기피하고 있다. 이러한 현상을 해소하기 위하여 금형 4벌에 의한 가공을 1벌의 금형에 통합시킨 캠금형 개발과 자동이송장치를 개발하였다. 그 결과, 프레스 1대와 금형 1벌로 무인화 작업을 할 수 있게 되어 직무기피요인을 해소하게 되고 제조원가 절감효과를 얻게 되었다

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.331-336
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• 2005

Four mosquito repellents, product A (aerosol), product B (liquid), product C (aerosol) and product D (lotion) were tested for their persistent repellency and quantity of DEET remained with the lapse was analyzed. In shirt term test with human (or 8 hours, product A (aerosol), product B (liquid), product C (aerosol) and product D (lotion) appeared over 95% repellency for eight, five, six and six hours. respectively. In long-term tests with shirt piece for 16 days, product A (aerosol) and product C (aerosol) showed 100% repellency for 10 days. In the assay of quantity of DEET remained in shirt pieces with the lapse of time, two products was decreased to the same pattern.

• Proceedings of the KAIS Fall Conference
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• 2005.05a
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• pp.287-289
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• 2005

Repellent effcacies of two natural aroma compounds. citronella and citronellal, against mosquitoes were evaluated both in field and in vitro. In vitro, the experiment was conducted with three controlled bands impregnated with $30\%$ citronella extract, $15\%$ citronella extract and $30\%$ citronellal extract, and with band impregnated $30\%$ citronella in field. Raw data was obtained by the means of counting numbers bitten by mosquitoes per unit time, namely human bait method. Comparative repellent efficacies of above three controlled bands were calculated at $86\%$, $73\%$, and $78\%$, respectively in vitro, and $80\%$ in field, showing high repellent effectiveness against mosquitoes. This estimation was also confirmed by t-test compared between control group and each experimental group.

• Korean journal of applied entomology
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• v.61 no.2
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• pp.369-376
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• 2022

Five different methanol extracts of plants were evaluated as a mosquito repellent against Aedes albopictus in nude mice model. The volatile components of plants were analyzed with GC-MS. The effective dose was the highest in Nepeta cataria with 72.9, 83.7, 86.4, and 97.3% efficiencies at 10, 50, 100, and 200 ㎍/mL, respectively. Nepeta cataria, Actinidia polygama, and Artemisia annua extracts were the most effective in duration time test. And there was no difference compared to negative control in the low mosquito repellent efficiency from 30 minutes. As a result of analyzing the volatile components of each plant, a total of 28 components in Mentha suaveolens, 19 components in Actinidia polygama, 27 components in Artemisia annua, 26 components in Nepeta cataria, and 19 components in Taraxacum platycarpum were detected. Especially, nepetalactone known as an effective ingredient of a mosquito repellent was identified (27.95 mg/Kg) in one of volatile components of Nepeta cataria. Overall, our results provide the possibility to develop mosquito repellents material using natural plants which contain various volatile components.

• Journal of the Korea Society of Computer and Information
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• v.27 no.2
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• pp.99-106
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• 2022

In this paper, We propose a method for identifying objects by setting inscriptions and landmarks of dogs. The phenomenon of abandoning dogs is on the rise, and the number of abandoned individuals is also rapidly increasing. These abandoned dogs are becoming wild animals, causing a lot of damage to people's daily life, causing serious problems. As a solution to this problem, the animal registration system is being implemented, but there is a phenomenon that some dog owners avoid the registration method that inserts a chip, so the complete registration system is not settled. When registering a dog, removing the avoidance of dog owners will help establish the companion animal registration system. In this paper, we present a technique to identify objects by setting inscriptions and landmarks of dogs so that dog owners can register their dogs in a friendly way to eliminate this avoidance phenomenon.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.3
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• pp.121-125
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• 2003

A switch box is metal box for electric wire pipes in building. In manufacturing this box, the first press is used to mold and the second to fifth presses are used to process four-sides of a box. So four presses, four molds and four workers are needed. This leads to raise the manufacturing cost including machine lease rent, molding fee, and wages. To make matters worse, the roaring sound, vibration, and dangers of safety accidents make employees avoid from working that job. To solve this problem, a new Handling Mechanism and a cam die which combined four-die-involving processes into one die process were developed. That results job automation of the Job with one press and one die. The job avoidance problem is solved and manufacturing cost is reduced as well.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.287-292
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• 2008

Repellent and acaricidal activities of eucalyptus oil, permethrin, and DEET against Leptotrombidium pallidum larvae, which are a vector transmitting tsutsugamushi disease, were evaluated under laboratory conditions using a filter paper impregnated method. The $LD_{50}$ values of eucalyptus oil and DEET were 0.025 and 0.018 $mg/cm^2$, respectively while that of permethrin was higher than 0.2 $mg/cm^2$. In the repellency test of these materials at 6.14 $mg/cm^2$, eucalyptus oil gave complete repellency, and the larvae crossed the treated zone killed. But permethrin showed 60% repellency at 9.20 $mg/cm^2$ and the mites croosed the zone were not killed. The percent repellency of DEET at 0.53 $mg/cm^2$ was 8.3 and 2.8 times higher than that of permethrin and eucalyptus oil, respectively. The acaricidal activities of emulsifiable concentrates-pump sprayers containing the eucalyptus oil as an active ingredient were assayed. The emulsifiable concentrates containing 1% and 3% eucalyptus oil showed weak mortality at 1 hour after treatment, while all ones containing more than 6% oil produced 100% activity against L. pallidum larvae. The mortality also increased as exposure time to the concentrates increase. These results suggest that the potential of eucalyptus oil highly expected to be used as a control or repellent agent against L. pallidum larvae may be very high.

• Journal of The Korean Association For Science Education
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• v.6 no.2
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• pp.63-72
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• 1986

과학교육은 학생들이 장차 과학 기술분야의 직업을 추구하도록 하는 것을 그 중요한 결실의 하나로 잡고 있다. 현재 한국은 과학과 기술의 발전을 교육의 주요목표의 하나로 삼고 있으며, 정부에서는 보다 많은 영재를 과학 기술분야로 유치하려고 여러 가지 정책을 펴고 있다. 그러나 이러한 정책도 결국은 학생이 과학 기술분야로 모여들지 않으면 그 효과가 없게 된다. 그런 점에서 학생들이 어떤 이유로 과학 기술분야를 선택하는지 혹은 기피하는지 그 원인을 아는 것을 중요한 과제라고 할 수 있다. 본 연구는 과학 및 기술분야의 직업을 갖게 되는데 결정적인 역할을 하는 고교생의 문 이과반 선택에 있어 그 진로결정에 영향을 주는 제 요인들을 규명하는데 목적을 두고있다. 연구대상은 대구시내외 남 녀 고교 1학년생 109명(문과 56명, 이과 53명)이었으며 조사방법은 설문지법을 사용하였다. 조사결과는 학생들의 문 이과반 선택에는 장래직업, 대학전공, 적성, 학과목에 대한 능력, 흥미 선호도, 가족 및 주위의 권유 등이 주요요인임을 보여주고 있다. 그중 문과를 지원한 학생들은 대체적으로 자신의 적성 이과과목에 대한 능력부족 인식, 내신 및 학력고사에서의 성적취득용이성 등 주로 자신의 내적 동기와 관련된 요인들을 들고 있는데 비해, 이과를 지원한 학생들은 밝은 직업전망, 가족 및 주위의 권유 등 외적인 동기도 큰 작용을 하고 있음을 보여 대조를 이루고 있다. 또 문과를 지원한 학생은 이과가 공부하기가 어렵고 성적을 올리기도 힘들어 이과를 기피한 경향을 보이는데 반해 이과 지원자는 문과를 기피하여 이과로 왔다는 응답은 별로 없는 점이 대조를 보였다. 본 논문은 이러한 결과가 던져주는 시사점과 과학교육의 개선책에 관한 제언을 제시하면서 결론을 맺고 있다.

• Journal of Environmental Policy
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• v.7 no.4
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• pp.57-73
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• 2008

This short paper considers the situation where an environmental policy could play a source of an exogenous background risk at an individual's wealth and analyzes the effect of such a background risk on the individual's decision making in a simple chance-improving model. Our analysis shows that risks at initial wealth generated by an environmental policy could be regarded as an exogenous background risk in many cases and that such a risk makes a risk averse person behave more risk aversely in some restricted decision making situations. A policy maker considering an environmental policy which would affect individuals' initial wealth should take into account that the environmental policy could affect an individual's seemingly irrelevant economics decisions via his or her wealth.

• 주택과사람들
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• s.220
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• pp.58-59
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• 2008

분양가 상한제에 전국적으로 13만 가구에 달하는 미분양 사태. 최근에는 공공 주택 용지 미분양 현상도 뚜렷하게 나타나고 있다. 건설 업계 전반에 주택을 지어도 사업성이 없다는 인식이 확산되면서 사업을 축소하거나 기피하는 업체들이 늘고 있어, 앞으로 주택 공급 부족 사태가 우려된다.