• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.12
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• pp.22-27
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• 2019

In this study, the flow rate and air resistance pressure were analyzed on models a, b, and c due to the front wing angle of the airplanes. Models a, b, and c have front wing angles of 120°, 100°, and 160°, respectively. The results of the flow analyses showed that the flow rate and air resistance pressure of model c were observed to be higher than models a and b. The airplane model with a larger angle to the front wing is thought to be the best model for flight. This result can be applied to development of the best in-flight airplane.

• The Science & Technology
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• v.29 no.7 s.326
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• pp.75-79
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• 1996

세계 최대 산업의 하나인 반도체산업은 최근 칩의 가격이 빠른 속도로 떨어지면서 그 앞날을 헤아리기 어렵게 되어가고 있다. 예컨대 16메가 D램의 경우 1995년 12월 45달러이던 국제시세가 1996년 4월에는 30달러로 떨어진데 이어 5월에는 18달러 그리고 6월초에는 13달러선까지 내려갔다. 그래서 세계의 주요 반도체메이커들은 서둘러 증산계획을 수정하거나 철회하고 있다. 예컨대 현재 월1천2백만개의 16메가D램의 생산량을 연말까지 1천4백만개로 증산하려던 삼성전자는 증산계획은 보류하고 현재 수준을 지키기로 하는가 하면 일본의 히다치사는 현재의 월 9백만개의 16메가 D램의 생산량을 연말까지 월1천5백만개로 증산하려던 계획을 철회했다. 반도체 값이 떨어지는 배경은 무엇이며 그 앞날은 어떻게 전개될까?

• Korean journal of applied entomology
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• v.25 no.1 s.66
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• pp.33-35
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• 1986

To discriminate features of H. assulta and H. armigera, this study was done in 1983. There is 7 spots on the forewing of H. armigera but not on that of H assulta. Ratios of length and width of valves were 5.6 on H. assulta and 4.3 on H. armigera. Numbers of setae on hindtibia of H. assulta and H. armigera were 8.5, 11.4, respectively.

• Bulletin of the Society of Naval Architects of Korea
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• v.26 no.3
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• pp.41-50
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• 1989

A basic formulation of the panel method, which is based on the potential field formulation, is reviewed for the case of two-dimensional hydrofoil problems. Numerical procedures to improve the computational efficiency of the panel method are suggested. By investigating local behavior of the flow around the trailing edge, a wedge type Kutta condition is formulated. By subdividing the trailing edge panels, where dipole strengths of the subdivided panels follow the local behavior of the potential values of the flow outside a wedge, the circulation around a hydrofoil is calculated accurately with a relatively small number of panels. The subdividing technique to improve the accuracy of the numerical Kutta condition is proved to be efficient. A local behavior of the flow around the leading edge is also investigated. By matching the flow around the leading edge with that around a parabola, a very accurate velocity distribution is obtained with relatively small number of panels. An accurate prediction of the stagnation point and the pressure distribution near the leading edge may contribute to improve the accuracy of cavity predictions and boundary layer calculations around hydrofoils.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.389-394
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• 2007

Numerical simulations are conducted to investigate the mechanism for force generation of an insect with tandem wing configuration. Various stroke amplitudes, stroke plane angles and phase difference between the fore- and hind-wings are considered. The Reynolds number is 150 based on the chord length and maximum translation velocity of the wing. When an insect requires high lift such as takeoff, it flaps its wings in parallel at a lower stroke plane angle and a bigger stroke amplitude than those in the hovering. With wings in counter-stroke, the lift fluctuations decrease, and moreover mean lift force decreases. Interactions among the fore-wing, hind-wing and vortices are examined to explain the force variations

• Korean journal of applied entomology
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• v.50 no.2
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• pp.167-170
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• 2011

Pseudoips fagana Fabricius belongs to the subfamily Chloephorinae (Lepidoptera: Noctuidae). Eggs of Pseudoips fagana were white and oviposited on oak leaves. There were five P. fagana larval instars, which were light green in color with four white crosslines. The larval period was approx. 24.4 days ($25^{\circ}C$, 16L:8D). Pupae were covered with a light-green membrane and silk. The wingspan of adults was approx. 15 to 18 mm. The color of the forewings of both sexes was bright green. The color of the hindwings was yellow in males and and white in females. First emergence was from early May to late June, and the second emergence was from early July to late August. Pseudoips fagana over-wintered as pupae.

• Korean Architects
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• no.1 s.381
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• pp.17-34
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• 2001

건축문화창달의 구심체로서 건축계 발전과 공익에 이바지하고 건축사 회원의 권익옹호 및 업무개선에 앞장서 온 대한건축사협회는 36년의 오랜 역사가 말해주듯 7천7백여 회원과 산하 16개 시도건축사회와 84개 지역건축사회로 구성된 조직력을 갖춘 전문자역사단체로 당당히 자리매김했다. 그러나 국내 여타 전문자격사단체들과 마찬가지로 지난 경제성장기 동안 제도의 틀 안에서 안정을 누려온 협회에 대해 그 기능과 역할을 재정비해야 한다는 건축계 안팎의 목소리가 점차 높아지고 있으며, 회원들의 요구 또한 적극적이며 다양해지고 있다. 여기에다 장기간 계속된 건축경기의 침체는 건축사사무소들의 경영상태를 크게 악화시켜 회비 수입에만 의존해온 협회의 재정상태를 어렵게 하므로써 향후 협회재정 자립의 필요성이 제기되고 있다. 더욱이 최근 정부의 규제개혁정책에 의해 설계도서신고제가 폐지되는 등 회원들의 의무규정이 상당부분 완화되었으며 또한 임의단체로의 전환과 함께 회원가입이 자유화됨에 따라 협회로서는 회원 결속력 강화와 자생력 확보라는 두 과제를 시급히 해결해야만 하는 상황에 직면해 있다. 특히 WTO에 의한 건축서비스시장 개방이 가속화되고, 이러한 무한경쟁시대에 대비해 정부가 각종 규제완화 정책들을 지속적으로 추진하는 등 앞날에 적지 않은 변화가 불어닥칠 것으로 예상됨에 따라 우리 건축사의 이익과 주장을 대변하는 창구로서의 기능 또한 중요시되고 있다. 따라서 전환기에 선 협회의 발전적 앞날을 위해서는 보다 다각적인 방향에서 그 위상을 재정립하고 또한 국제화ㆍ개방화ㆍ정보화시대에 제 기능과 역할을 다할 수 있는 전문조직으로 거듭나야 할 것이다. 이에 본지에서는 이번 좌담을 통해 협회의 기능과 역할을 재조명해 보고 아울러 사회적 요구에 부응하는 전문자격사단체로서의 위상을 확립해 나가기 위한 다양한 의견을 듣는 자리를 마련하였다.

• Journal of Life Science
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• v.28 no.3
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• pp.357-360
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• 2018

This study developed a method to minimize rice damages and enhance timely control by accurately classifying Whitebacked Planthopper (WBPH). The body size of the 1st-3rd instar was 1.5-2 mm, and the body size of the 4-5 instar was 2.5-3.5 mm. In the third instar, the ratio of the front wing bud and the back wing-bud was 1:1. The fourth instar occupied 3/4 of the front wing-bud, and the 5th instar showed that the front wing-bud covers the back wing-bud. It was confirmed that the 1st instar does not have a sensory plate, the 2nd instar has 2-3, the 3rd instar has 4-5, the 4th instar has 6-9, the 5th instar has 10-15, and the adult instar has 15-20 sensory plates. The female spawning organs were reddish when the spawning horn was inserted. WBPH showed that the larvae of 2-3 larvae most actively feed on rice, and the damaged area was the stem of rice near the ground. In addition, a partial black wound was observed after the feeding. WBPH-susceptible 'Chucheong' was yellowish, and early growth was slower than that of 'Cheongcheong', which was resistant; moreover, a difference between susceptibility and resistance was observed. The identification of the number of such wounds in the bioassay will be a better basis for understanding the difference in susceptibility between WBPH strains and cultivars. These results will be used as basic data for cultivating the WBPH-resistant varieties of rice.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.91-95
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• 2005

This study was conducted to investigate the morphological characteristics, overwintering sites and behavior for each stage of Oligota kashmirica benefica (Coleoptera: Sthphylinidae). Egg was oval type, yellow, 0.3 mm size. Larva exuviated 3 times and the last (3rd) instar, length 1.6 mm, wide 0.4 mm, became dermata pupa in soil. Adult was lightish dark-brown, and coriaceous forewing covered a half of abdomen. O. kashmirica benefca mainly overwinters with adult at Japanese cedar (Cryptomeria japonica) windbreaks of orchards, but it did not diapause in greenhouse during winter.

• Vending industry
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• v.2 no.6 s.7
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• pp.95-98
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• 2003

대중문화의 꽃 ‘스타되기’를 향한 청소년들의 꿈을 타깃 마케팅 포인트로 삼아 의욕적으로 진행했던 오디션 동영상 자판기 사업이 의욕만큼 시장이 따라주지 못하고 있다. 한때 유망시장으로 많은 업체들의 시장가세를 불러 일으켰으나 현재로서는 $3{\~}4$개 업체 만이 현재보다는 내일의 가능성을 보고 소신 있는 시장 개척을 진행하고 있을 뿐이다. 이중 '하이 스튜디오' 오디션 동영상 자판기를 전개하는 SM게임은 제품 차별화 및 지속적인 부가성능 보완작업을 통해 이 시장의 새로운 앞날을 제시하고 있다. SM게임의 최근 사업행보를 통해 오디션 동영상 자판기 시장의 현실과 미래를 살펴봤다