• Korean journal of applied entomology
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• v.47 no.4
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• pp.435-445
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• 2008

Due to internal feeding behavior, the oriental tobacco budworm, Helicoverpa assulta ($Guen\acute{e}e$), infesting hot pepper has been regarded to be effectively controlled by targeting egg and neonate larval stages just before entering the fruits. This study aimed to develop an efficient biological control method focusing on these susceptible stages of H. assulta. An egg parasitoid wasp, Trichogramma evanescens Westwood, was confirmed to parasitize the eggs of H. assulta. A mixture of Gram-positive soil bacterium, Bacillus thuringiensis subsp. kurstaki, and Gram-negative entomopathogenic bacterium, Xenorhabdus nematophila ANU101, could effectively kill neonate larvae of H. assulta. A sex pheromone trap monitored the occurrence of field H. assulta adults. The microbial insecticide mixture was proved to give no detrimental effects on immature development and adult survival of the wasp by both feeding and contact toxicity tests. A combined treatment of egg parasitoid and microbial pesticide was applied to hot pepper fields infested by H. assulta. The mixture treatment of both biological control agents significantly decreased the fruit damage, which was comparable to the chemical insecticide treatment, though either single biological control agent did not show any significant control efficacy. This study also provides morphological and genetic characters of T. evanescens.

• Asian Journal of Turfgrass Science
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• v.21 no.1
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• pp.51-67
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• 2007

Survey was initiated on insect pest species damaging the landscaping trees in golf courses to get the basic information for the development of insect management program. Four country clubs were selected as survey sites; Tongue Country Club and Youngwon Country Club in Gyeongnam, Daegu Country Club in Gyeongbuk, and Dongrae Benest Golf Club in Busan. We found that 60 species of 44 genera in 34 families of six orders from 88 species of 54 genera in 33 families of 22 orders surveyed. Most landscaping trees were damaged by one or two species of insect pests, but tree species such as Robinia pseudoacacia, Prunus leveilleana var. pendula, Castanea crenata, Quercus dentata, and Q. variabilis were damaged by more than five species of insects. Most insect species damaged one or two tree species. However, Adoretus tenuimaculatus(Coleoptera: Scarabaeidae) damaged 67 tree species of 41 genera. The Coleoptera and Honmoptera species were 36.4% and 36.3% of the total insect species, respectively. Insect pest occurring in high frequency was 9% of total insect species, while infrequent one was 73%. The insect species with chewing and sucking mouth part types were 49% and 51%, respectively.

• Korean Journal of Social Welfare
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• v.37
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• pp.357-379
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• 1999

In recent years, the subject of peer rejection in school settings has received increased attention in the massmedia and counseling literature. This study focused on the effect of individual and environmental factors on peer rejection. Dependent variable was the number of perpetrating peer rejection and independent variables were psychological, behavioral, familial factors, exposure of peer rejection and perception about school policies. Ordered Probit model was employed because of the nature of limited dependent variable. The data were collected from 714 middle-school student in Seoul. Major findings were as follows. First of all, the adolescents who has aggression and problematic behaviors in school were more likely to participate in peer rejection. Second, negative parent-children relationships and the family structure didn't have significant effects on peer rejection. And there were not a significant effect of attitude toward academic value and academic achievement on peer rejection. Third, environmental risk factors such as negative peer relationship and the exposure to rejection had a significant increasing effect on peer rejection. But consistent school policies didn't have a significant effect. In conclusion, this study confirmed that peer rejection in school settings was affected by school environment such as negative-peer relationship, and exposure to rejection. Therefore, comprehesive and systematic intervention programs should be required to ensure that all the pupils at school have a right to learn in a safe and fear-free environment.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.469-477
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• 2012

Ostrinia larvae feed the pods and stem of red bean and seriously damage the bean production from farmers. In this study we investigated biological and developmental characteristics including field collection, host feeding preference, artificial rearing diet, morphological and molecular taxonomical identification, and pheromone analysis for an Ostrinia sp. in Korea. The male adults have massive tibia in the middle legs and 3-lobed uncus in the genitalia. The partial nucleotide sequences of mitochondrial cytochrome oxidase I (COI) and II (COII) were not corresponded to those DNA sequences from other Ostrinia species reported previously in Japan and China. Host plants for this species are also different from the previous species reported. In the gas chromatography (GC) analyses, (Z)-9-tetradecenyl acetate was not detected from the pheromone gland of our species while the component as a sex pheromone was found in O. zaguliaevi and O. zealis, With taken results, we conclude this Ostrinia species in Korea is Ostrinia scapulalis or closely related species. When larvae collected in a fall were incubated in the outdoor condition, they emerged to adult between June and July in the next year. The result indicates that the winter diapause could be started in late larval stage. In addition, we developed a semi-synthetic artificial diet adopted for mass rearing of the O. scapulalis in laboratory.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.269-277
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• 2003

Some species of true bugs have become serious problems in rice, upland crops, and tree fruits. It would be meaningful to understand research status by reviewing articles on those true bugs in Korea. Articles on those bugs published in several scientific Korean journals were reviewed, except articles on true bugs on rice plants; CD Part 1 included classification and morphological studies on eggs and larvae of Piesma spp., on external genitalia of Gonopsis affinis, and on spermathecae of some Podopinae and Asopinae species. $\circled2$ Development and growth analysis of Piesma sp., P. maculata, and 2 species of Coreidae were reviewed in part 2. $\circled3$ In part 3 we reviewed with major pest bug species on soybean, sweet persimmon, yuzu, citrus, chrysanthemum, and Cynanchum wilfordii, and insect fauna in mountain areas. $\circled4$ In part 4, damage levels in soybean, sweet persimmon, yuzu, grapes were reviewed. $\circled5$ ID In part 5 we reviewed seasonal occurrence patterns of Halyomorpha halys, Plautia stali, Riptortus clavatus in sweet persimmon orchards, of some species in soybean fields, of Nysius plebejus on chrysanthemum, and of Tropidothorax cruciger on Cynanchum wilfordii. $\circled6$ Chemical control methods in a sweet persimmon orchard, in grapevine yards, in a soybean field, and in a chrythansemum field were introduced in part 6. Some laboratory bioassay on insecticides against R. clavatus were mentioned, too. $\circled7$ Finally in part 7, researches on transmission by Halyomorpha halys and Cyrtopeltis tenuis of micoplasma-like organism which is a pathogen of paulownia withces' -broom to Catharanthus roseus were reviewed.

• Korean journal of applied entomology
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• v.33 no.2
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• pp.114-121
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• 1994

Population densities of intermediate nymphs and egg saw of Matsucoccus thunbergianae, a major insect pest of Pinus thunbergiona in southern coastal area of Korean peninsula, were est~mated. Tree samples of ca. 10cm D.B.H. were collected from old infestation area and newly invaded area. The numben of plimaly branches per tree were not significantly different by the locality, but those of secondaly and smaller branches were smaller in old infestation area The numbers of intermediate nymphs per tree in old infestation area and in newly invaded area were 10.8 and 13.1 times more than those on the trunk, respectively Approximately between 4, 200 and 208, 500 nymphs per tree were estimated. Men secondaw and smaller bmnch samples collected from the basal part of middle crown height, or from the central or the basal part of lower crown height, the number of samples required for the emr range of 20% were 21 and 11 far 10-20cm and 20-3 crn long branches, respectively. Approx~mately 63.6% of egg sacs of the whole tree were on the trunk. The node/intemode bearing the largest branch had the highest egg sac density; including that, four adjacent nodes/intemodes had ca. 37% of egg saw on the trunk.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.185-191
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• 2014

Corythucha marmorata (Uhler) belonging to the family Tingidae (Hemiptera) has been reported in Korea. In 2013, surveys were conducted to study its morphological characteristics, geographical distribution, and host plants. The adult is brown white and 2.77-3.28 mm in length, and the mature nymph is yellowish brown. Heavily infested trees appear yellowish white because they are fed on by the nymphs on the under surface of host plants. C. marmorata were found between early June and late October, and their numbers peaked in early July to late August. In 2013, the occurrence of C. marmorata was confirmed in 27 cities and counties nationwide, and 8 families and 24 species of host plants were identified. C. marmorata feeds on the following major host plants: Conyza canadensis, Aster pilosus, Helianthus annuus, Artemisia princeps, Rudbeckia bicolor, and Solanum melongena.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2001.04a
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• pp.76-76
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• 2001

종이가 가지는 공극 특성은 종이의 광학적 특성에 지대한 영향을 미칠 뿐만 아니라 인쇄용 지로서 사용될 때 잉크의 다공성 기질로서 잉크의 잔류 특성에도 큰 영향을 미친다. 특히 다공성 기지의 표변에 유동성이 뛰어난 물질이 가해 질 때, 이들의 유동 특성은 기질이 지 니고 있는 공극율과 공극의 분포에 따라 큰 차이를 나타내는 것으로 알려져 있다. 이러한 공극성은 백상지의 경우 사용된 펄프의 혼합 비율과 충전제의 사용량 그리고 펄프의 고해 정도에 따라 종이의 공극울이 달라진다. 종이의 공극성이 광학적 특성과 밀접한 연관성을 지니는 것은 종이의 광산란 계수를 결정하기 때문이다. 잘 알려진 바와 같이 종이의 광산란 계수는 빛의 산란과 관계되어 백색도와 백감도에 영향을 미친다. 그러나 도공지가 인쇄 용 지로 사용 될 경우, 도공지 표면에 도피되는 영크층은 도공지가 가지고 있는 구조적 특성을 변화시킬 수 있는 제3의 요인으로 간주 될 수 있다. 결국, 인쇄가 완료된 종이의 경우 원지층, 도공층 그리고 잉크층으로 구성된다. 따라서 다양 한 공극 구조를 가지는 기질위에 잉크가 도피될 경우 기질의 공극 특성에 따라 잉크 조성분 의 침투 거동에도 많은 차이가 있을 것으로 예측된다. 잉크의 구성 요소를 살펴보면 잉크의 색상을 결정하는 안료, 단일의 각 안료 입자를 도포하여 인쇄판으로부터 종이까지 운송시키 는 기능과 인쇄기에서 잉크의 유동성을 유지하고 종이 또는 기타 피인쇄체에 전이된 후에는 건조막을 형성하는 비히클 그리고 각종 기능성 첨가제로 구성되어 있다. 동일한 성분으로 구성된 잉크를 사용하여 각각 공극성이 다른 피인쇄체 위에 인쇄 될 경우 이들 조성분의 이 동과 표면 잔류 특성에 변화가 있을 것으로 생각된다. 즉 공극성이 풍부한 기질에 도피된 잉크는 반대의 경우와 비교하여 보다 많은 조성분이 종이의 공극 속으로 침투하게 될 것이 다. 이 과정에서 특히 미세한 안료 입자의 경우 피인쇄체의 표면 공극을 채우고, 비히클의 경우 미세한 공극속으로 침투되어 경화됨으로써 피인쇄체가 지니고 있는 공극량을 감소시커 게 될 것이다. 그리고 피인쇄체의 각종 형태의 공극으로 침투된 잉크의 양에 반비례적으로 피인쇄체의 표변에 잉크가 잔류하게 될 것이다. 따라서 본 연구에서는 여러가지 안료를 사용하여 각각 다른 공극 특성을 지니는 도공지를 제조한 후 이들이 가지는 공극 특성과 잉크의 잔류 거동에 대해 고찰해 보고자 하였다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.2
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• pp.313-321
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• 2000

This paper deals with a kind of the half-space interfacial problem in time domain, requiring the calculation of the horizontal electric field generated by a tiny impulsive current source located horizontally at the interface between an isotropic upper half-space and a uniaxially anisotropic lower half-space. With the Cagniard-de-Hoop method adapted for our interfacial case, we obtain the explicit-form solution for this electric field. We also investigate the impulse radiation in the radial direction. The impulse components of Dirac $\delta$-function type in transient waveforms are important for the understanding of the interfacial far-field characteristics. The uniaxial case is a generalization of the isotropic one, and the explicit solutions of the uniaxial problem in this paper reduce to the solutions of the isotropic problem if the anisotropy is removed.

• The Korean Journal of Pesticide Science
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• v.8 no.3
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• pp.162-167
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• 2004

In recent years, the diamondback moth (DBM), Plutella xylostella has become one of the most important pests for cruciferous plants in the world. A new type of the thiophosphoryl pyrazole insecticide, called KH502. Its outstanding insecticidal activity could be effective alternative against DBM. We investigated, using the comparative molecular field analysis (CoMPA) method, The structure-activity relationship of various thiophosphorylpyrazole derivatives and structure requirement for insecticidal activity. We found, the key substructures in pyrazole derivatives, the trifluoro-methyl group and the thiophosphoryl group. Both play an important role in insecticidal activity with the binding site. The three dimensional Quantitative Structure Activity Relationship (QSAR) analysis could provide useful information for the structural requirements of pyrazole insecticide as an insecticidal and the design of a new insecticide.