• 대한수학회논문집
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• 제11권1호
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• pp.259-263
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• 1996

Let G be a topological group and X a G space. For a given nonequivariant vector bundle over X there does not always exist a G equivariant vector bundle structure. In this paper we find some sufficient conditions for nonequivariant real line bundles to have G equivariant vector bundle structures.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1643-1646
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• 2003

Drawing is a mechanical operation that attenuates thick material to an appropriate thickness for the next processing or end usage. When the input material has the form of a bundle or bundles made of very thin and long shaped wire or fibers, this attenuation operation is called "bundle drawing" or "drafting" Drafting is being used widely in manufacturing staple yarns. which is indispensable for the textile industry. However, the bundle processed by this operation undertake more or less defects in the evenness of linear density. Such irregularities cause many problems not only for the product quality but also for the efficiency of the next successive processes. Since long there have been many researches tying to find out factors affecting the irregularity of linear desity, to obtain optimal drafting conditions, to develop efficient measuring and analysis methods of linear density of bundle, etc., but there exists yet no fundamental equation describing the dynamic behavior of the flowing bundle during processing. In this research a mathematical model for the dynamic behavior of the bundle fluid is to be set up on the basis of general physical lows representing physical variables, i.e. linear density and velocity as the dynamic state of bundle. The conservation of mass and momentum balance was applied to the fluid field of bundle. while the movement of′ individual material was taken into account. The constitutive model relating the surface force and the deformation of bundle was introduced by considering a representative prodedure that stands for the bundle movement. Then a fundamental equations system could be simplified considering a steady state of the process. On the basis of the simplified model, the simulation was performed and the results could be confirmed by the experiments under various conditions.

• 정보통신설비학회논문지
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• 제1권1호
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• pp.40-50
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• 2002

기존의 SNMP 에이전트는 컴포넌트화 되어있지 않고 코드 이동성을 제공하기 위한 프레임워크가없기 때문에 원격에서 온라인으로 에이전트의 MIB 코드를 새롭게 추가한다거나 에이전트 자체를 업그레이드하기 어려웠다. 이런 문제를 해결하기 위해서 OSGi프레임워크 상으로 다운로드 가능한 SNMP 에이전트 번들을 SNMP 메시지 처리를 위한 SNMP 에이전트 기본 번들과 관리 정보 수집을 위한 MIB번들로 나누어 설계하였으며 번들 서버가 인증을 거친 후 MIB 번들을 동적으로 업로드 할 수 있도록 하기 위하여 다운로드 서버 번들과 사용자 인증 번들을 추가하였다. 또한 네트워크 관리자가 장치에 탑재되어 있는 MIB 번들의 상태 정보를 모니터링할 수 있도록 하기 위하여 MB-MIB를 설계하였다. 본 논문에서 설계한 OSGi 기반 SNMP 에이전트 번들을 사용함으로써, 관리자는 원격에서 온라인으로 관리하고자 하는 MIB 모듈과 SNMP 에이전트 기본 모듈을 업그레이드시킬 수 있으므로 다변화하는 대규모 네트워크를 관리하는 시간과 비용을 줄일 수 있다.

• 대한기계학회논문집A
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• 제35권5호
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• pp.517-523
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• 2011

전방십자인대 부상은 스포츠 활동 중에 빈번하게 발생하며 주로 수술적 치료가 행해진다. 전방십자인대는 전내측과 후외측 다발로 구분되는데 주로 전내측 다발만 재건되는 한다발 재건술이시술되고 있다. 후외측 다발은 경골의 내회전을 복원하는데 효과적이라는 실험 결과가 보고된 바있지만 부상을 야기하는 역동적인 착지동작에서의 역할에 대한 연구가 필요하다. MRI 영상을 이용하여개발된 3차원 슬관절 모델에 인체실험 자료를 입력한 시뮬레이션으로 착지동작 시에 후외측 다발 및두다발 재건술이 얼마나 경골의 내회전을 제어하는지 알아보았다. 본 연구는 후외측 다발 방향의재건이 전내측 다발보다 착지동작 시에 경골 내회전을 효과적으로 감소시키며 두다발 재건술 또한슬관절 회전 안정성을 향상시킴을 밝혔다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.333-334
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• 2008

Overhead transmission lines are classified by the number of sub conductors per phase. Korean transmission lines use two, four, or six-conductor bundle. Bundle of conductors must have spacers or spacer dampers which keep the proper distance between sub conductors. They can prevent conductors from being vibrated or twisted due to the wind. As for the two-conductor bundle, alternating current flow generates absorption force between sub conductors which may cause a collision of sub conductors. To prevent sub conductors from being vibrated, twisted, and collided, spacer or spacer damper installation method is designed considering vibration characteristics of sub conductors. We have spacer installation method for four or six-conductor bundle lines. However, we don't have it for two-conductor bundle ones. So we have installed spacers at regular intervals in two-conductor bundle lines, and it caused rigid body oscillation of conductors due to the wind which made a flashover between conductors. This paper introduces a vibration characteristic analysis of two-conductor bundle and proposes a spacer installation method for two-conductor bundle lines.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권7호
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• pp.542-549
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• 1999

Corona discharges form at the surface of a transmission line conductor when the electric-field intensity on the conductor surface exceeds the breakdown strength of air. In order to decrease the electric-field intensity on the conductor surface, a new 6 conductor bundle has been studied. This bundle, hybrid conductor bundle, consists of using a larger subconductor at the bottom two conductor positions in the 6-conductor bundles of each phase of the line. The electric field on these two larger subconductors is reduced which in turn reduces the corona noise. It is shown that this is a better solution for decreasing the electric-field intensity than ether the conventional bundle or the asymmetric bundle proposed by EPRI.

• 대한관절경학회지
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• 제9권2호
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• pp.109-114
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• 2005

Recently, the interest on anatomical ACL reconstruction with double bundle technique is increased to reproduce the original load distribution, and kinematics of the knee. We developed an arthroscopic double bundle ACL reconstruction technique using autogenous quadriceps tendon with 2 splitted graft and patellar bone plug. The anteromedial bundle and posteolateral bundle of the ACL is replicated with each splitted graft of quadriceps tendon and fixed with biodegradable interference screw on the 2 femoral tunnels. The patellar bone plug of quadriceps tendon is fixed with biodegradable interference screw within the 1 tibial tunnel. We suggest that our technique using quadriceps tendon may be an alternative in arthroscopic double bundle ACL reconstruction.

• 한국환경과학회지
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• 제9권2호
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• pp.173-176
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• 2000

This study was carried out to investigate the filtration characteristics of membrane modules according to hollow fiber dispersion for direct solid-liquid separation of activated sludge. 2 bundle, 4 bundle, and 10 bundle, and 10 bundle module used in this experiment according to hollow fiber dispersion was manufactured at laboratory and permeate flux and transmembrane pressure(TMP) of each module were observed under a suction pressure of 0.5kgf/c$m^2$. As the hollow fibers were dispersed, permeate flux was increased and TMP was decreased. Permeate flux and TMP of each module was 15.0 $\ell$/$m^2$.h and 31.8 cmHg for 2 bundle, 16.0 $\ell$/$m^2$ .h and 17.4 cmHg for 4 bundle, and 20.4 $\ell$/m2 .h and 31.8 cmHg for 10 bundle. In conclusion, the membrane fouling is expected to be decrease by maintaining lower TMP with hollow fiber dispersion.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(1)
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• pp.41-47
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• 1995

A parametric study bas been performed for the various refueling schemes of CANDU 6 reactor loaded with reference DUPIC fuel. The optimum discharge burnup was determined such that the peak bundle power is minimized for the equilibrium core. Based on the results of instantaneous core calculation using patterned random age distributions, it was decided to perform the refueling simulations only for 2-bundle and 4-bundle shift refueling schemes. The 600 FPD simulation has shown that the operational margins of the channel and bundle power to the license limits are 7.9% and 17.1%, respectively, for 2-bundle shift refueling scheme. The 4-bundle shift refueling scheme also satisfies the license limits and the operational margins of the channel and bundle power are 7.1% and 9.8%, respectively. The result of refueling simulation indicate the possibility of using reference DUPIC fuel in current CANDU 6 reactor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전력기술부문
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• pp.406-410
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• 2001

For 4-conductor bundle transmission line spacer damper are equipped so as to keep the spacing between sub conductors. For 4-conductor bundle the subspan spacing of a spacer damper is determined and applied in order that the bundle may get restored to a normal state when 4-conductor bundle is rolled by rigid body vibration due to wind. But 4 conductors of 345kV 4-conductor bundle transmission line were twisted by the angle of $315^{\circ}$ for the first time korea. In this paper, we will analyze the reason of the power line twisting of 4-conductor bundle which occurred for the first time in korea and offer the preventive countermeasures for this