• 한국소음진동공학회논문집
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• 제19권3호
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• pp.274-281
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• 2009

The carbon fiber epoxy composite material and aluminum have many advantages over other materials because of their high specific stiffness and good fatigue characteristics. Basically, the propeller shaft of automobile requires bending frequency of higher than 2,700 Nm and high natural frequency of higher than 9,200 rpm occurred by fast revolution. For this reason, natural frequency and torsion torque characteristics of hybrid shaft was studied in variation of its outer-diameter and thickness. Vibration and torque characteristics of hybrid shaft were compared by torsion tester, natural frequency experiments and FE analysis. Designed hybrid shaft satisfied its vibration and torque characteristics when its outer-diameter was 60 mm and thickness was 5 mm. Therefore, hybrid material enables to manufacture one piece structure hybrid propeller shaft rather than current two piece structure.

• 태양에너지
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• 제19권3호
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• pp.93-100
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• 1999

The objective of this experimental study was to investigate the characteristics of heat transfer and air flow in two-dimensional impinging jet system, in which hybrid rods have been set up in front of heating surface in order to increase heat transfer. The shape of hybrid rods had a cross section made with a half of circular cross section and that of rectangular. This time, the clearance from hybrid rod to heating surface(C=1, 2, 4mm) and the pitch between each hybrid rods(P=30, 40, 50mm) changed for the transition region(H/B=10). And this result compared with the experimentation without hybrid rod. As a result, heat transfer performance was best under the condition of C=1mm, in case clearance changed, and as the pitch is 30mm, it is largely influenced by eddies and acceleration in case pitch of hybrid rod changed.

• 한국벤처창업학회:학술대회논문집
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• 한국벤처창업학회 2021년도 춘계학술대회
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• pp.131-136
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• 2021

산업 패러다임과 트랜드의 변화 속에서도 저성장, 고령화는 뉴 노말 시대의 가장 큰 문제점으로 대두되고 있다. 이에 따라 각자도생이 필요하며, 결국 창업이 대세인 시대가 되었다. 성공적인 창업을 위해서는 많은 준비와 실패 노하우의 축적이 필요하나 실패를 용납하지 않는 우리 사회분위기상 이는 쉽지 않다. 조사에 따르면 창업 장애요인으로 '창업실패 및 재기에 대한 두려움', '창업 준비부터 성공까지의 생계유지'가 많은 부분을 차지하고 있다. 이러한 장애요인을 줄이는 방법으로 Hybrid창업을 제시할 수 있으나 국내 많은 기업이 직장인의 겸직을 제한하는 탓에 Hybrid창업이 활성화되지 못하고 있고 관련 연구도 거의 없는 수준이다. 그러나 52시간 근무제로 직장인이 투잡(two-job)을 통한 수익창출 기회는 증가하였고, 고용불안과 은퇴이후를 고민하는 직장인들이 우회 창업하는 경우도 적지 않다. 이러한 Hybrid창업 현상은 조기은퇴, 고령화의 영향으로 계속 증가할 것으로 예상됨에 따라 관련 연구를 축적할 필요가 있다. 본 연구의 목적은 직장인의 Hybrid 창업의도에 미치는 영향요인을 탐색하는데 있다. 본 연구에서는 직장인의 창업가 특성, 창업역량, 경력지향성과 Hybrid창업의도간의 관계와, 직장인의 조직불안 인식의 조절효과를 검증하고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.96-98
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• 2005

This paper presents a new two-phase linear hybrid stepping motors (LHSM), which has two windings per phase and one of them shares the other phase winding. The proposed motor shows a unique ability to deliver low cogging force without any particular complex control scheme and additional power electronics hardware in micro stepping control. An analytical and experimental comparison between conventional and proposed LHSM is evaluated to confirm the effectiveness of the proposed design.

• KSBB Journal
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• 제6권2호
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• pp.123-128
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• 1991

The production of bassinosteroid-like substances of two hybrid types of Korean rice, Jangseongbyeo, Taebackbyeo were investigated. The shoots at the maximum tillering stage were extracted and purified by solvent fractionation, silica gel adsorption chromatography Sephadex LH-20 chromatography, charcoal adsorption chromatography, Bondesil chromatography and HPLC of reverse phase, successively. Biological activities of each purification step were monitored by the rice lamina inclination test. Higher activities against the rice lamina inclination test in the each purification step showed that the shoots of two cultivars biosynthesize brassinosteroids. Two cultivars also showed a similar distribution of biological activities of endogenous brassinosteroids detected by HPLC.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 F
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• pp.2149-2151
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• 1997

Open loop microstepping control of two phase hybrid step motors provides enhanced step resolution, smoothness of operation, and removes most of the objectionable resonance phenomena. In this paper, we discuss the technigues about design and implementation of microstepping driver of two phase hybrid step motors.

• Industrial Engineering and Management Systems
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• 제14권1호
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• pp.22-31
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• 2015

In this paper, a two-stage hybrid flow shop problem is considered. Specifically, there exist identical parallel machines at stage 1 and two dedicated machines at stage 2, and the objective of the problem is to minimize makespan. After being processed by any machine at stage 1, a job must be processed by a specific machine at stage 2 depending on the job type, and one type of jobs can have different processing times on each machine. First, we introduce the problem and establish complexity of several variations of the problem. For some special cases, we develop optimal polynomial time solution procedures. Then, we establish some simple lower bounds for the problem. In order to solve this NP-hard problem, three heuristics based on simple rules such as the Johnson's rule and the LPT (Longest Processing Time first) rule are developed. For each of the heuristics, we provide some theoretical analysis and find some worst case bound on relative error. Finally, we empirically evaluate the heuristics.

• Journal of Life Science
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• 제12권2호
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• pp.43-46
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• 2002

Kinesin Superfamily Protein 1A (KIF1A) is an anterograde monomeric motor transporting a subset of synaptic vesicle precursors and plays an important role in neuronal function and survival. Here, f have used the yeast two-hybrid system to identify the proteins that interacts with the tail region of KIF1A. Calmodulin was found to interact specifically with the tail region of KIF1A. Calmodulin regulates many diverse cellular functions by modulating the activity of the proteins that interact with it. KIF1A interacts with calmodulin in the yeast two-hybrid assay, which is proved by immunoprecipitation with calmodulin in brain fraction. These results indicate that KIF1A is associated with calmodulin, suggesting that calmodulin may be a key role in the regulation of anterograde transport of synaptic 1 vesicle precursors.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.294-301
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• 2011

A two-dimensional hybrid flaw solver has been developed for the accurate and efficient simulation of steady and unsteady flaw fields. The flow solver was cast to accommodate two different topologies of computational meshes. Triangular meshes are adopted in the near-body region such that complex geometric configurations can be easily modeled, while adaptive Cartesian meshes are, utilized in the off-body region to resolve the flaw more accurately with less numerical dissipation by adopting a spatially high-order accurate scheme and solution-adaptive mesh refinement technique. A chimera mesh technique has been employed to link the two flow regimes adopting each mesh topology. Validations were made for the unsteady inviscid vol1ex convection am the unsteady turbulent flaws over an NACA0012 airfoil, and the results were compared with experimental and other computational results.

• 한국통신학회논문지
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• 제17권11호
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• pp.1264-1270
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• 1992

Morphological 필터는 다양한 structuring element로서 morphological 연산으로 구성된다. 두개의 기본적인 morphological 연산은 erosion과 dilation이다. 두 연산에 기본을 두고 OC, CO 필터가 정의된다. 가우시안 잡음이 포함된 이미지의 잡음을 제거할 경우 OC 필터의 성능이 CO의 성능보다 우수함을 확인하였다. 본 논문에서는 이미지 처리에 있어서 하이브리드 메디안 필터를 구성하여 다른 필터 보다 화질의 선명도를 개선하고 컴퓨터 시뮬레이션을 통하여 해석하였다.