• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.4
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• pp.279-281
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• 2004

The pulp fabric impregnanted 100% natural insect repellent was evaluated in an environmental chamber (laboratory, mongsanpoo beach, taejo Mt, naksan and seolak beach) for their repellent efficacy against insects. The results showed significant average repellency of 91%, 78%, 90%, and 93% of laboratory, mongsanpoo beach, taejo Mt, naksan and seolak beach, respectively, during the 1hour of exposure period.

• Proceedings of the KAIS Fall Conference
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• 2004.06a
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• pp.285-287
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• 2004

$100\%$천연향을 이용하여 제작, 개발된 해충기피제의 기피력을 테스트하였다. 해충기피제를 착용한 그룹과 착용하지 않은 그룹으로 구분하여 실험실에서 사육한 모기와 서해안에 위치한 몽산포 해수욕장, 동해안에 위치한 낙산 및 선악 해수욕장과 천안에 있는 태조산에서 해충에 대한 기피력을 측정하였으며, 각 그룹별로 5명씩 5회에 걸쳐 각 회당 1시간동안에 흡혈개체로부터 물린 갯수를 확인하여 이들의 평균값을 계산하였다. 그 결과, 실험실에서는 $91\%$, 몽산포 해수욕장에서는 $78\%$, 낙산 및 설악 해수욕장에서는 $93\%$, 태조산에서는 $90\%$의 기피력을 보여주었으며, 이는 상당히 탁월한 기피 효과를 나타내었다.

• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.243-249
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• 2005

We investigated the repellency of eight mosquito repellents against Culex pipiens pallens and Aedes albopictus, and the quantity of DEETs were analysed by using gas chromatography. Ae. albopictus showed higher bloodsucking efficacy than Cx. pipiens pallens of the two subjects mouse and human hands, and human hand was more efficacious method for mosquito bloodsucking efficacy than mouse. Among the eight repellents were tested with mouse as subjects for eight hours, product C, G, and H were high repellency than others. In the case of human hands as subject, product C was highly effective than above other products. The DEET quantities of eight repellants varied from 7.31 g to 38.9 g in 100 g contents and we ascertained that there was a correlation between mosquito repellency and the DEET quantities remained after the treatments. It was evidenced from the long term test with shirt piece, in this test the Ae. albopictus attack was increased when the DEET quantity decreased below 40%.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.2
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• pp.81-85
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• 2013

The stored-product insects have been a serious problem during the entire process of distribution on the food industry. Especially, the Indian meal moth (Plodia interpunctella) is one of stored-product insects which causes harm through penetrating into the food packaging. The objective of this study was to develop the anti-insect packaging material with fennel (Foeniculum vulgare) oil (FO). The FO has been selected for insecticidal substance against P. interpunctella, which was tested by fumigant toxicity assay. An anti-insect sachet was prepared by FO and filterpaper placed in a small paper bag. Repellent test was performed to evaluate the repellent activity of anti-insect sachet. In addition, the controlled release of FO from the anti-insect sachet was determined at $28^{\circ}C$ by gas chromatography (GC). It was demonstrated that FO was an effective substance against P. interpunctella. The mortality of FO was 56% at 800 mg/0.5 L in 120 h. In repellent test, the FO sachet showed effective repellency against P. interpunctella. The developed anti-insect sachet could be a promising source for insect repellent materials in food packaging.

• 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 Life Science
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• v.23 no.5
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• pp.637-642
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• 2013

This study was performed to evaluate the rodent repellency and antimicrobial activity of natural oils. Thirteen natural essential oils were evaluated for repellent efficacy against rodent feed intake suppression activity. Salvia sclarea (sage), Cinnamomum zeylanicum (cinnamon) Cymbopogon citratus (lemon grass), and Syzygium aromaticum (clove) showed the best repellent efficacy among tested natural oils. Antimicrobial activity against Gram-negative (four strains) and Gram-positive (four strains) bacteria were evaluated using four natural oils, which showed high efficacy on the rodent repellent test. Syzygium aromaticum showed antimicrobial activity against all tested bacteria and Cymbopogon citratus, Cinnamonum zeylanicum, and Salvia sclarea showed antimicrobial activity against some tested bacteria.

• 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.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.877-880
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• 2017

Impeller blades in the centrifugal compressor are subjected to static loads due to the high-speed rotation and steady aerodynamic forces. At the same time, aerodynamic excitations by the interaction between the impeller and the diffuser vanes(DV) periodically excite the impeller blades in resonant conditions, which may lead to high cycle fatigue (HCF) and eventually result in failure of the blades. In order to predict the structural response accurately, the aerodynamic excitation and the major resonant conditions were predicted by performing the unsteady flow analysis and modal analysis using ANSYS. Next, a unidirectional forced vibration analysis was performed by using fluid-structure interaction (FSI) method, and the safety of HCF was evaluated based on the results.

• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.133-139
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• 1974

The objective of this study is to compare the effects of raw materials as method of speeding up mounting of matured silkworm, for reducing concentrated labor during mounting periods. The results obtained from this study are summarized as fellows： (1) Quercus acutissima Carrs showed the most remarkable effect of repellent. Persicaria blumei Gross and Artemisia asiatica Nakai were followed in order. The rest repellents were also expected to be applicable. considering known material (silk-up) with lower mounting percentage. (2) The effective methods of preparation of repellent were to make distillate. Decocted solution type was considered to be the easiest way of preparation. (3) It seemed to be that there was little effect of repellent on the qualities of cocoon and silk. (4) When a repellent was applied to a silkworm bed, immatured silkworms were observed to mount. Thus it suggests that the repellent will give remarkable effects only when the degree of matured of silkworms is uniform.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.325-329
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• 2012

In this study, 1, 2 and 4% aqueous extracts of common cocklebur (Xanthium strumarium) fruit were tested against pulse beetle (Callosobruchus chinensis) for development of an environmental friendly control methods of this pest. The common cocklebur fruit extracts showed effects on mortality, repellency, fecundity and adult emergence of C. chinensis and inhibited pulse grains from damage. The 4% extract showed the highest mortality (26%) and repellency rate (53.3%) at 2 day after treatment and 3 hours after treatment, respectively. The studied insects revealed lowest fecundity (113.7 female-1), highest percentage of adult emergence inhibition (37.0%) and lowest percentage (42.3%) of seed damage when they were reared on pulse grains mixed with 4% extract. This finding indicated that common cocklebur fruit extract may be used in the integrated management of pulse beetle for protecting stored grains.