• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.248-248
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• 2013

저소음, 저진동이 장점인 맥동관형 냉동기 및 이를 이용한 크라이오 펌프를 국산화하는 연구개발사업이 상당히 진전되어 첫 번째 시제품을 완성했다. 3개월 여에 걸쳐 냉동기 냉동능력, 진동 및 펌프 냉각시간을 포함해서 질소, 수소 또는 알고에 대한 펌프 배기속도, 배기용량, 최대유량, 교차값, 알곤회복시간 등 규격, 비규격을 통틀어 모든 평가항목을 망라하는 펌프 배기 성능시험을 완료했다. 성능평가결과에 나타난 시제품의 장단점을 분석하여 보완 및 개선점을 찾고 이를 완제품 제작에 반영하려고 한다. 내경 14인치인 크라이오 펌프 시제품의 질소 배기속도는 목표치를 30% 정도 상화하여 4,600 L/s가 나왔고 배기용량은 약 45만 $mbar{\cdot}L$에 달했으며 교차값은 2,200 $mbar{\cdot}L$로 측정되었다. $5{\times}10^{-8}$ mbar 기준 알곤 회복시간은 2분 정도로 5분 이내라는 기준을 만족했다. 한편 20 K까지 펌프 냉각시간이 135분이므로 15분 이상 단축이 필요한데 이는 열차폐 특히 배플의 열적설계를 개선함으로써해결하려고 한다. 그리고 수소에 대한 배기성능 개선을 위해 활성탄 어레이의 제작공정을 표준화할 필요가 있다.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.4
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• pp.415-422
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• 2015

The flow field structures of dual jet-in-cross-flow were examined experimentally for in-lined perforated damage holes configuration using particle image velocimetry. Ensemble averaged in-plane velocity and vorticity data in the jet were determined to study the mean jet structure. Jets are formed by pressure differences between upper and lower airfoil surface. The flow structure of vicinity of the thru holes consist of a vortical structure that wrap around the jets like a horseshoe and develop further downstream through a pair of stream-wise vortices. The shape, size and location of the horseshoe vortex were found to be dependent on the angle of attack. In spite of the existence of battle damage holes, the effect on the control force was insignificant when the damage size was not large enough.

• Korean Journal Plant Pathology
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• v.10 no.1
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• pp.25-28
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• 1994

One hundred fifty four our of 262 isolates of Fusarium oxysporum obtained from healthy plant tissues of various crops and their rhizosphere soil were found to be nonpathogenic to cucumber plants. The nonpathogenic isolates were frequently found from sesame plant tissues and rhizosphere soil, but less from healthy plant tissues of cucumber and water melon. When the 154 nonpathogenic isolates were preinoculated into cucumber seedlings, and then challenge-inoculated with Fusarium wilt pathogen, 21 isolates protected effectively cucumber plants from Fusarium wilt infections. A year later, 9 out of 21 isolates fully sustained their protective effect. Among 9 isolates showing good protective effects, 7 were isolates from cucumber plants. These 9 isolates except 1 isolate, were not pathogenic to water melon, chines melon, tomato and sesame.

• Korean Journal Plant Pathology
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• v.10 no.1
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• pp.29-33
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• 1994

One hundred fifty four out of 262 isolates of Fusarium oxysporum obtained from healthy plant tissues of various crops and their rhizosphere soil were found to be nonpathogenic to cucumber plants. The nonpathogenic isolates were frequently found from sesame plant tissues and rhizosphere soil, but less from healthy plant tissues of cucumber and water melon. When the 154 nonpathogenic isolates were preinoculated into cucumber seedlings, and then challenge-inoculated with Fusarium wilt pathogen, 21 isolates protected effectively cucumber plants from Fusarium wilt infections. A year later, 9 out of 21 isolates fully sustained their protective effect. Among 9 isolates showing good protective effects, 7 were isolates from cucumber plants. These 9 isolates, except 1 isolate, were not pathogenic to water melon, chinese melon, tomato and sesame.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.11
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• pp.108-114
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• 2000

In this paper, a new adaptive cross-coupling control(CCC) method with an improved contour error model is proposed to maintain contouring precision in high-speed nonlinear contour machining. The proposed method utilizes variable controller gains based on the instantaneous curvature of a contour and the feedrate command. The proposed method is evaluated and compared with the conventional CCC for nonlinear contouring motion through computer simulations. The simulation results show that the proposed CCC improves the contouring accuracy more effectively than the existing method.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.04a
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• pp.309-312
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• 2001

본 연구에서는 상류부 교차로에서 발생하는 교차로 막힘 현상으로 인해 진행방향의 녹색시간의 손실이라는 장애가 발생하게되는 상황을 고려하기 위해 진행차선의 정체도를 도입하여 교통 혼잡상황에 적절히 대응할 수 있는 퍼지 교통신호 제어기를 제안한다. 먼저 입출력 공간을 균등 분할한 퍼지 교통신호 제어기를 구성하고, 소속함수 수정알고리즘에 의해 제어기를 수정한다. 실험을 통해 고정식 제어기, 균등 분할한 제어기와 수정된 제어기의 성능을 교차로 지체시간, 진입율과 통과율 면에서 비교하였다. 실험 결과는 수정된 제어기가 다른 제어기들에 비해 향상된 성능을 보여주었다.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.789-792
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• 2004

본 논문에서는 일반적인 실린더 맵에서 구현하지 못하는 시점이동의 한계를 보완하고 현실감 있는 실시간 영상기반 환경 탐색을 위해 완전시야를 갖는 직각 교차 실린더 맵을 제안한다. 제안한 알고리즘에서는 한 대의 카메라와 하나의 볼록거울의 조합으로 이루어진 카타디옵트릭 카메라를 이용하여 수평, 수직 두 개의 전(全)방향 이미지를 얻고, 이미지를 실린더에 매핑한 뒤 두 실린더를 합하는 방법을 이용하였다. 실험에서는 제안한 방법이 기존의 방법에 비해 시선이동 뿐만 아니라 환경 탐색에 자유로워짐을 확인한다.

• The Korean Journal of Pesticide Science
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• v.14 no.3
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• pp.247-254
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• 2010

Two-spotted spider mite, Tetranychus urticae was collected from the rose greenhouse in Chilgok, Gyeongbuk Province in December 2000. This population has been selected for ten years with bifenazate (over 450 times), and increased 855.9 fold in resistance as compared with susceptible strain (S). Cross resistance of bifenazate resistant (BR) strain to eight miticides was investigated. The BR strain exhibited high and low cross resistance to acequinocyl (614.0 fold) and to chlorfenapyr (9.1 fold), respectively. Against fenazaquin (0.3 fold) and fenpyroximate (0.1 fold), however, showed the strain negatively correlated cross resistance. Each strain collected in Choeng-ju (CJ), Kang-jin (KJ), and Chung-ju (CUJ) showed 5.5-, 964.5-, and 21.8-fold resistance to bifenazate, respectively. The detoxifying enzymes of the BR strain showed 1.6-fold activity in cytochrome $P_{450}$-dependent monooxygenase ($P_{450}$) as compared with susceptible one. By comparing the mitochondrial cytochrome b (cytb) sequence, G126S point mutation was detected in the BR and KJ strains.

• Korean journal of applied entomology
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• v.33 no.4
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• pp.230-236
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• 1994

Dicofol susceptible two-spotted spider mite(S) which was selected by 150 times of dicofol treatment showed 27 5-fold increase in resistance as compared to S strain. Inheritance of resistance and crossresistance in selected strain($R_d$) were investigated. There were differences oi susceptibility in the dicofol concentmtion-moltaliity relationships between $F_1$ progenies (R♀, XS♂, R♂, XS♀) obtained from reciprocal cross with the S strain and $R_d$, strain. Degree of dominance of the $F_1$ progenies (R♀, XS♂, R♂, XS♀) were -0.29 and -0.72 in adult females and -0.42 and -0.93 in adult males, respectively. These results suggest that inheritance of dicofol resistance is controlled by an incomplete recessive. $R_d$ strain exhibited a high level of cross resistance to amitraz, and also showed cross resistance to pyrethrotd acaricides, acrinathrin and bifenthnn. $R_d$ strain showed non-cross reslstancz to abamectin, chlolfenson, clofentezine, cyhexatm, fenbutatin oxlde, fenpyroximate, hexythiazox, monocrotophos, propargite and tetradifon, but negatively correlated cross-resistance to azocyclotin and fenbutatin oxide belonging to tin acaricides.

• Management & Information Systems Review
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• v.37 no.3
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• pp.65-81
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• 2018

This study estimated the long-run and the short-run price and income elasticity of crude oil demand by using the ARDL model in Korea. First, the long-run cointegration relationship existed between crude oil demand and price or income in the ARDL-bounds tests. Second, the long-run own price, the cross price elasticity and the income elasticity were both statistically significant elastic and sensitive in the ARDL. Third, there was autocorrelation of the residuals, but no misspecification errors and heteroscedasticity, and then the residuals showed a normal distribution. And the CUSUM & CUSUMSQ tests showed that the coefficients were stable. Fourth, the short-run own price, the cross price elasticity and the income elasticity were both statistically significant elastic and sensitive in the ARDL-RECM. The ECM with the short-run dynamics showed rapid adjustments in the long-run equilibrium of oil demand after the economic crisis. In the short-run, the sensitivity of crude oil demand to price and income changes has moved in the same direction as the long-run case. Korea, depending too much on foreign crude oil, is vulnerable to the shocks of oil prices, so rising oil prices can certainly have a negative impact on Korea's trade balance. And the elasticity of long-run oil prices may help to control and manage Korea's oil demand. The government needs to strengthen monitoring of the country's policies and market trends related to crude oil, establish strategies to customize national policies and market conditions, and strengthen active market dominance efforts through pioneering new market and diversification.