• Title/Summary/Keyword: natural history

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Description of Osorius myujechinesis n. sp. (Coleoptera, Staphylinidae) from Korea (한국산 투구반날개 속(딱정벌레 목, 반날개 과)의 1신종)

  • Young Bok Cho
    • Animal Systematics, Evolution and Diversity
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    • v.14 no.2
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    • pp.99-103
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    • 1998
  • A new species, Osorius mujechinensis, is described based on SEM microphotographys of the extenal structures and illustrations of the aedeagus. This new species was collected at Mujechi Moor, Mt. Chongjoksan, Ulsan, Korea. The subfamily Osoriinae in Korea now comprises two recorded species of the genus Osorius.

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New Records of Three Yponomeutine Moths (Lepidoptera: Yponomeutidae) from Korea

  • Sohn, Jae-Cheon;Park, Kyu-Tek;Cho, Soo-Won
    • Animal Systematics, Evolution and Diversity
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    • v.26 no.2
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    • pp.153-156
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    • 2010
  • Two species of Yponomeutinae new to Korea, Euhyponomeutoides trachydeltus (Meyrick) and Thecobathra anas (Stringer), are reported. In addition, occurrence of Yponomeuta anatolicus (Stringer) in Korea is confirmed with proper collection of data. The adults and genitalia for the three species are illustrated.

Aphids, Plants nd Other Organisms

  • Eastop, V.F.
    • Korean journal of applied entomology
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    • v.34 no.1
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    • pp.1-8
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    • 1995
  • The relationships between aphids, plants, other organisms and some physical components of the environment are reviewed. Aspects considered include year cycles, polymorphism fecundity, relationship of different groups of aphids with particular groups of plants, honeydew, alarm pheromones, aposematic colouring, camouflage, colour variation within species, morphological variation within species, multivariate analysis and problems of its interpretation, parasitism, stridulating mechanisms, predators, coevolution of plants and aphids, plant galls, trapping aphids and the interpretation of trap catches, an curation of aphid collections. References are given to sources of information about aphids, with special reference to the Korean fauna.

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Two New Marine Psammocinian Sponges (Demospongiae: Dictyoceratida: Irciniidae) from Korea

  • Lee, Kyung-Jin;Sim, Chung-Ja
    • Animal cells and systems
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    • v.8 no.3
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    • pp.139-143
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    • 2004
  • Two new species of the genus Psammocinia (Dictyoceratida, Irciniidae), P. conulosa n. sp. and P. ulleungensis n. sp., are described from Namhaedo Island and Ulleungdo Island, Korea. Psammocinia conulosa n. sp. seems to be close to both P. amodes Cook and Bergquist, 1998 and P. hawere Cook and Bergquist, 1996 on the basis of the skeletal structure. However, these three species are clearly separated by the following differences: Shape of P. amodes is spatulate and thin, with a broad blade narrowing to a semi-cylindrical stalk; P. hawere forms cups with a shallow excavated bowl, and attached to the substratum by a narrow base. The whole surface of the new species is very finely conulose. Psammocinia ulleungensis n. sp. is similar to P. gageoensis Sim and Lee, 2001 in shape, but this species is easily distinguished from P. gageoensis by the simple skeletal structure.

Inelastic Hysteretic Characteristics of Demand Spectrum -Focused on Elasto Perfectly Plastic Model- (요구스펙트럼의 비탄성이력특성 -완전탄소성모델을 중심으로-)

  • 이현호
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.04a
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    • pp.367-374
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    • 2000
  • This study investigates the effect of hysteretic characteristics to the Inelastic Demand Spectrum (IDS) which was expressed by an acceleration(Sa) and a displacement response spectrum (Sd). Elasto Perfectly Plastic(EPP) model is used in this study and inelastic demand spectrum (Sa vs, Sd) are obtained from a given target ductility ratio. For a given target ductility ratio IDS can be obtained by using nonlinear time history analysis of single degree of system with forth five recorded earthquake ground motions for stiff soil site. The effect EPP model under demand spectrum is investigated by ductility factor and natural frequency. According to the results obtained in this study IDS has dependency on ductility factor and natural frequency.

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Optimization of a vehicle component under dynamic fatigue (동적 피로를 고려한 자동차 부품의 최적설계)

  • 이정준;주병현;이병채
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.898-901
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    • 2004
  • Generally, in case the natural frequency of vehicle components is larger than the reversing frequency of load history, we can obtain the analysis results with small errors. But in case of having the low natural frequency, we must avoidably carry out the dynamic analysis, and it requires much time and storage. Specially executing the fatigue analysis for vehicle components requires more time. To this end, it is not easy that we accomplish the optimization considering fatigue for the vehicle component based on the dynamic analysis. In this research we introduce an efficient method which performs the fatigue analysis based on the dynamic analysis. Finally as making the response surface we optimize the vehicle component under dynamic fatigue.

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