• 한국물환경학회지
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• 제31권1호
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• pp.1-11
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• 2015

In this study, the attraction efficiency of the by-pass fishway installed at Dalseong Weir in Nakdong River was assessed according to operation of the attraction waterway by using River2D which is a two-dimensional physical habitat simulation model. The model was calibrated and validated through the measured water elevation. The attraction efficiency of the fishway was evaluated at the low flow condition because the target fish, Zacco platypus (Z. platypus), have moved frequently up and downstream at the spawning season from April to June. From simulation results, it can be deduced that the attraction efficiency at situation of open attraction waterway is superior to that of close attraction waterway. Also it is shown that velocity field at inner region of the fishway is suitable for migration of the fish.

• 한국항공운항학회지
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• 제26권2호
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• pp.47-53
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• 2018

In this paper, we investigate a collision avoidance algorithm for unmanned aerial vehicles using potential field based on the relative velocity of obstacles. The potential field consists of the attraction force and the repulsive force that are generated for the target and the obstacles. And the field can be classified into the attractive potential field generated by the target and the repulsive potential field generated by the obstacle, respectively. In this study, we construct an attractive potential field as a function of the distance between the UAV and the target position. On the other hand, a repulsive potential field is created by a function of distance and the relative velocity of the obstacle with respect to the UAV. The proposed potential field based collision avoidance algorithm is evaluate through simulations.

• 한국기계가공학회지
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• 제15권2호
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• pp.89-96
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• 2016

Growing concerns regarding environmental pollution have increased the demand for green vehicles. Green vehicles include electric vehicles, compressed natural gas vehicles, fuel cell vehicles, and vehicles running on fuels such as bio diesel or an ethanol blend. CNG vehicles are equipped with a cylinder valve installed in a high-pressure vessel to control the CNG flow. For this purpose, the optimum design of cylinder valve solenoid is necessary to secure at driving a CNG vehicle. In this study, electromagnetic field analysis to ensure the reliable operation of the solenoid was conducted by using a Maxwell V15. The electromagnetic field analysis was performed by magnetostatic technique according to distance between magnetic poles in order to predict the attraction force. Finally, the attraction force was validated through comparison between the Maxwell results and the measurement results. From the results, the error of attraction force was found to be 2.85 N to 6.5 N under the testing conditions.

• KIEAE Journal
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• 제9권5호
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• pp.77-84
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• 2009

This study was initiated by the fact that Kangwon Land and large sized resorts was failed the financial benefit to the local residents. This research analyzed the best important tourist resource among the main tourist resource by perception interviewing local residents and related professionals. This study shows that the leisure resource was most important resource field in Jeong-Seon. So more attention to the leisure resources and investment them. Among natural attraction resources 'Hwa-Ahm cave and Hwa-Ahm mineral water' is estimated to have most potential for the strategic financial support. In leisure sector 'High One resort' is judged to be more important attraction resource by professionals but a case of local residents 'Dong-gang Rafting' and 'Rail Bike' were estimated more important resources rather than 'High One resort;. Lastly, in cultural resources, although the importance is a bit behind natural attraction and leisure resources, 'Jeong-Seon 5th day market' and 'Araree village' should be the core linking other related cultural resources. In order to activate tour industry and development of Jeong-Seon area, it is necessary to find identify of regional owned attraction resources and to build tourist attraction infra structure by selecting core bases of existing major attraction points and linking other various resources to those core bases.

• 한국생산제조학회지
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• 제25권3호
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• pp.157-163
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• 2016

Green vehicles include electric vehicles, natural gas vehicles, fuel cell vehicles (FCV), and vehicles running on fuel such as a biodiesel or an ethanol blend. An FCV is equipped with a cylinder valve installed in an ultra-high pressure vessel to control the hydrogen flow. For this purpose, an optimum design of the solenoid actuator is necessary to ensure reliability when driving an FCV. In this study, an electromagnetic field analysis for ensuring reliable operation of the solenoid actuator was conducted by using Maxwell V15. The electromagnetic field analysis was performed by magnetostatic technique, according to the distance between magnetic poles in order to predict the attraction force. Finally, the attraction force was validated through comparison between the Maxwell results and measurement results. From the results, the error of attraction force ranged from 4.53 % to 9.05 % at testing conditions.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1996년도 추계학술발표회 논문집
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• pp.34-44
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• 1996

N-machine produces more than input energy at above 3000 rpm. any space energy is absorbed when the N-machine is rotating at a very high velocity. Laws of electromagnetics verify that normal conduction is due to that electrons moves from one three-dimensional crystallizing ${\pi}-bonding$ orbital to next. The ${\pi}-far$ infrared rays are generated from the resonance and rotation of the electrons on the orbitals of three-dimensional crystallizing ${\pi}-bonding$ atoms. Material in universe is composed of ${\pi}-rays$, which have alternative outward electric field. If the alternative outward electric fields of the ${\pi}-rays$ are resonant each other they make attraction force, which is the gravity. The collection of space energy is due to a attraction force between the radially alternating electric field and the ${\pi}-far$ infrared rays in the space. Electrons flow by absorbed density difference of ${\pi}-far$ infrared rays along a conduction wire, which also verifies that normal electron conduction is due to a flow from one three-dimensional crystallizing ${\pi}-bonding$ orbital to next.

• 한국도서관정보학회지
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• 제45권1호
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• pp.103-123
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• 2014

이 연구는 관광학의 학문적 특성과 분류체계를 비교 분석함으로써, 관광학의 분류특성과 문제점을 분석하고 이를 토대로 KDC 제6판 관광학의 분류체계 수정 전개 방안을 제시하였으며, 연구결과를 요약하면 아래와 같다. 첫째, 관광학의 학문영역은 관광일반, 관광주체, 관광객체, 관광매체로 구분되고 있지만, 분류체계는 대부분이 관광학을 관광일반과 관광객체 일부에 한정하고 있으며, 관광객체나 관광매체는 해당 주제에 분산 배치하고 있다. 둘째, 국립중앙도서관의 관광학 유별 자료 분석결과, 상대적으로 관광경영, 관광유형, 관광개발, 관광심리 및 관광객, 관광산업, 컨벤션 등의 주제어에 빈도수가 높게 나타났다. 셋째, 분류항목의 수정 전개는 원칙적으로 관광학의 학문적 특성과 주제어 분석을 바탕으로 하였으며, 혼란을 줄일 수 있도록 가능한 한 기존의 KDC 분류체계를 유지하였다. 또한 이를 바탕으로 상관색인어도 추가하였다.

• 한국응용곤충학회지
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• 제62권3호
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• pp.131-137
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• 2023

호박꽃과실파리(Z. scutellata)는 박과작물에 피해를 주는 중요한 해충이다. 현재 큐루어(Cuelure)는 국내에서 검역 대상 해충으로 규정된 오이과실파리, 타우과실파리, 및 퀸슬랜드과실파리와 더불어 호박꽃과실파리 수컷 성충의 예찰에 다양한 제형으로 활용되고 있다. 본 연구는 액체, 고체, 및 왁스제형의 큐루어에 대한 호박꽃과실파리 수컷 성충의 야외 유인효과를 검증하기 위한 것으로 2021년 4월부터 10월까지 제주 2개 지역과 경북 1개 조사에서 2주 간격으로 모니터링하였다. 호박꽃과실파리의 발생밀도가 높은 제주지역에서는 7월부터 8월에 액체와 왁스제형의 큐루어에 호박꽃과실파리가 더 많이 유인되어 통계적인 유의차가 있었으나, 호박꽃과실파리의 발생밀도가 낮은 경북지역에서는 제형별 유인력에 차이가 없었다. 야외조사 결과를 바탕으로 액체와 왁스제형의 큐루어가 호박꽃과실파리 수컷 성충 예찰에 권장되며, 이 두 제형의 큐루어에 유인되는 검역 대상 과실파리류의 국내 예찰에 효과적일 수 있다.

• 한국환경농학회지
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• 제38권2호
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• pp.104-109
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• 2019

BACKGROUND: The invasive hornet Vespa velutina nigrithorax has becomes a public concern in rural and urban South Korea. The technologies are necessary to develop a way to counter V. velutina. In an effort to develop a way to counter V. velutina, we found that a bacillus strain, named Bacillus sp. BV-1, produces volatile compounds that attract V. velutina. METHODS AND RESULTS: Field trials of V. velutina attraction were performed using plates and traps containing BV-1 cultures grown on sugar medium. When the sugar medium and sugar-grown BV-1 cultures in the plates were placed close together, V. velutina visited preferably the plates with the BV-1 cultures. Significantly more V. velutina were caught in the traps containing BV-1 cultures than in those containing only sugar medium. Headspace solid-phase microextraction coupled with GC/MS analysis of BV-1 cultures detected 2-methyl-1-propanol, 3-methyl-1-butanol, 3-methylbutanoic acid, ethyl hexanoate, 2-pheylethanol, ethyl octanoate, and ethyl decanoate as the major volatiles. CONCLUSION: BV-1 cultures were suggested as potential agents for managing V. velutina as they produce volatile compounds that attract the hornet.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1303-1307
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• 2004

MAGLEV is the vehicle which can run in levitated condition by the electro-magnets, and the vehicle can run without any contact condition. In MAGLEV system achieving a high magnetic field for minimum weight is a noteworthy goal. Unfortunately the two aspects of this goal high field and low weight are contradictory. Suitable designs must be sought using optimization techniques. In this paper, magnet attraction force is calculated and conformed by experimental data for designing a electro-magnet.