• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.600-606
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• 2019

The study site was the camping area in the Hwarang Amusement Park in Danwon-gu, Ansan-si. Study activities were conducted three times a week from July 20, 2018, to August 1, 2018. A control site, natural enemy site, and Bti(Bacillus thuringiensis israelensis) site were selected. The analyses included habitat environment and species composition analyses, community analysis, correlation analysis, and similarity analysis. The water quality analysis found no significant difference in water quality over the study period (p>0.05). A total of 4,818 individuals, 38 species, 22 families, and 11 orders were observed during the study period. The natural enemy site observed during the study period had a similar species composition as the control site. The Bti site differed from other sites by the low number of species and individuals present. According to the community analysis, the natural enemy site was a stable community and the Bti site was an unstable community during the study period. Diptera showed negative associations with temperature and water temperature and mosquito larvae showed significant correlations with temperature and water temperature. The similarity analysis showed that the control site and the natural enemy site were 61.11-73.68% and the Bti site showed 30.77-56.00% similarity.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.29-30
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• 2000

오늘날 수중가청음을 이용하여 어류의 유집과 구집에 많은 활용도를 보여주고 있다. 어류는 소리에 대하여 민감한 반응을 보이는데, 대표적으로 천적이 내는 소리에 의한 도피 행동, 같은 어류가 내는 식이음에 따른 색이 행동, 그리고 음원 주변에 모이는 유집 행동 등이 있다. 소리는 내는 어종들은 여러 수종이 알려져 있으며, 어류의 가청범위는 16∼13,000Hz 범위에서 가장 민감한 반응을 나타낸다고 한다.(전촌; 1977, 김;1981) (중략)

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.8
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• pp.15-21
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• 2020

We improved the sound pressure of the speaker and allowed the speaker to rotate 360 degrees to improve the effectiveness of the acoustic type bird repellent system. The prototype of the bird repellent system was developed by evaluating sound pressure characteristics by distance and direction and installing orchards. As a result of the evaluation, the extermination sound pressure increased from a distance of about 30 m to a maximum of 60 m, and through the rotary speaker, the extermination distance could be widened in all directions without specific direction.

• Korean Journal of Organic Agriculture
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• v.17 no.2
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• pp.227-236
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• 2009

This research was carried out to investigate the seasonal occurrence of major pests and the effects of releases of natural enemies for biological control of the major pests in eggplant greenhouse. A total of 8 pest species in 7 families were identified. Among these pests, Myzus persicae, Aphis gossypii, Frankliniella occidentalis, Tetranychus urticae and Trialeurodes vaporariorum were the dominant species in eggplant greenhouse. Two aphid species occurred mainly from May to June, but their populations decreased rapidly from July. The population density of F. occidentalis was high from June to July and T. urticae and T. vaporariorum were abundant from July to September during the growing season of eggplant. In the trials of biological control of pests, aphids could be suppressed within the range of $87{\sim}97%$ by two times releases of Chrysopa pallens eggs. F. occidentalis and T. urticae could be suppressed within the range of $76{\sim}90\;and\;87{\sim}91%$ by three times releases of Orius sauteri adults, respectively. The releases of C. pallens eggs and O. sauteri adults were as effective as three times applications of insecticides for the control of aphids, F occidentalis and T. urticae from May to September.