• Structural Engineering and Mechanics
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• 제5권5호
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• pp.663-677
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• 1997

Bond-slip behavior between reinforcement and concrete under push-pull cyclic loadings is numerically investigated based on a reinforcement model proposed in this paper. The equivalent reinforcing steel model considering the bond-slip effect without taking double nodes is derived through the equilibrium at each node of steel and the compatibility condition between steel and concrete. Besides a specific transformation algorithm is composed to transfer the forces and displacements from the nodes of the steel element to the nodes of the concrete element. This model first results in an effective use in the case of complex steel arrangements where the steel elements cross the sides of the concrete elements and second turns the impossibility into a possibility in consideration of the bond-slip effect in three dimensional finite element analysis. Finally, the correlation studies between numerical and experimental results under the continuously repeated large deformation stages demonstrate the validity of developed reinforcing steel model and adopted algorithms.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.836-842
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• 2001

The more sophisticated patterns of propagation model is presented in this paper, which includes three different source characteristics. The spherical, cosine and dipole radiation characteristics compared and sound event level and the maximum sound level are calculated by experiment and calculation. It is shown that patterns of propagation has dipole characteristics for low speed range(below about 150km/h) at electric multiple system. We know that push-pull high speed system(maximum speed: 300km/h) has cosine characteristics of noise propagation. For this purpose, We conduct the experiment of noise and know the empirical formula of noise level and radiation coefficient K. This model of simulation is conducted through point source array model at wheel/rail contact point by using program and experimental formula. We can guess prediction of profile, flat and wear of wheel by above modeling in near field.

• 설비공학논문집
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• 제15권11호
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• pp.970-978
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• 2003

This paper aims at suggesting design guidelines for a perimeter-less HVAC system that contributes energy savings. Perimeter-less HVAC system is one that relieves difficulties such as handling mixing loss, uneven radiative environment, and maintenance and repair. It prevents heat load gained through window and outdoor wall without modifying a previously equipped building skin system. In this paper, we conducted a large-scale model experiment to see how the push-pull air flow would handle indoor heat to obtain an optimized perimeter-less design, and then we plan to perform several kinds of CFD (computational fluid dynamics) cases through numerical simulation

• 한국사회복지학
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• 제63권2호
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• pp.233-260
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• 2011

본 연구는 1980~2005년 OECD 15개국 중고령 남성의 취업률 추이 및 취업률 결정요인을 분석하여 중고령 남성의 노동시장참여를 지원할 수 있는 방안을 살펴보고자 한다. 자료는 OECD, ILO, LIS이다. 분석은 노동시장참여의 상태의존성과 패널개체의 이질성을 반영한 동적패널모형으로서, 도구변수를 사용한 Arellano and Bonds(1981)의 차분 GMM으로 하였다. 분석결과, 55~64세 남성의 취업률은 1990년대 중반까지 감소하였으나, 그 이후 증가하고 있다. 둘째, 1980~2005년 기간동안 중고령 남성의 취업률은 상태의존성이 강하게 작용하였고, 정적인 기간효과가 나타났다. 공적 연금의 유인효과는 크게 나타나지 않았고, 노동시장의 배출요인이 부적인 영향을 미쳤다. 셋째, 1996~2005년은 노동시장위험완화요인인 임시직 비율이 중고령 남성의 취업률에 기여하였고, 빈곤이 노동의 메커니즘으로 나타났다.

• 대한기계학회논문집
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• 제9권2호
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• pp.140-149
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• 1985

본 연구는 오오스테나이트계 STS 316 스테인레스강에 대하여 온도 550.deg. C의 대 기중에서, 변형율제어에 의한 인장-압축에 크리이프 유지시간을 갖는 고온저사이클 피 로시험을 하여 변형율폭 및 크리이프 유지시간이 피로수명에 미치는 영향과 파단면을 주사형 전자현미경으로 관찰하여 크리이프-피로 상호작용이 피로파단면에 미치는 크리 이프 효과를 실험 고찰하였다.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2013년도 제47차 동계학술대회논문집 21권1호
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• pp.133-136
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• 2013

본 논문에서는 오늘날의 경쟁적인 경영환경은 기업들이 공급사슬을 어떻게 관리할 지에 더욱더 관심을 기울이고 있다. 고객들은 제품을 구매하는 데 있어 보다 큰 가치, 보다 빠른 주문여행, 그리고 보다 적극적인 서비스를 강조하고 있다. 공급사슬 관리 응용시스템의 실행과 성과측정을 알아보고 수요주도의 공급사슬 방식을 통하여 공급사슬관리시스템의 비즈니스 운영과 그 가치를 도출하고자 하였다.

• 한국산업보건학회지
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• 제8권2호
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• pp.163-177
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• 1998

Computational Fluid Dynamics(CFD) was applied to predict air flow around the hoods : circular hoods, square hoods, and push-pull hoods. A commercially available CFD software, CFD-ACE(Ver. 4.0), was tested, which is based on the finite volume method using the ${\kappa}-{\varepsilon}$ turbulence model. Numerical results were compared with the experimental, analytical and numerical results from other studies. CFD solutions showed an excellent agreement with the previous experimental and numerical results. It is promising that CFD techniques could be applied on the variety of complex problems in the industrial ventilation engineering.

• 한국경영과학회지
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• 제29권3호
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• pp.9-21
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• 2004

Semiconductor industry is the one whose supply chain network is distributed all over the world. And it has different characteristics with other manufacturing industries as reentrancy, binning, substitution. In this paper, we suggest supply chain models for the semiconductor industry, consisting of production and distribution chains, where manufacturing characteristics are considered. Three policies for the production chain and two policies for the distribution chain are suggested and formulated mathematically. Six combination policies are tested for the evaluation of performances with example. It is shown that the supply chain is operated, if production and distribution are coordinated and managed based on the demand information, without inventory, as efficiently as the chain with inventory.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.227-230
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• 2001

This paper deals with a bidirectional ac-dc converter used in ups system application. We propose a Voltage-Source-Charge-Pump-Power-Factor-Correction(VS-CPPFC) ac-dc converters. First of all, we propose a charge pump power-factor-correction converter. Secondly, we derive and analyse a unity power factor condition. The proposed topology is based on a half-bridge for the primary and a current-fed push pull for the secondary side of a high frequency isolation transformer. The advantage of bidirectional flow of power achieved by using the same power components is that the circuit is simple and efficient. And the galvanically isolated topology is specially attractive in battery charge/discharge circuits in ups system. We design equivalent model for the steady-state circuit and analyse operation waveforms for each mode. We show that the proposed model can be applied to ups system by simulation processes.

• 대한안전경영과학회지
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• 제8권3호
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• pp.125-141
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• 2006

If do not become whole optimization because enterprise's individual enterprise internal determinate improvement effort is associated with activity in enterprise SCM, competitive power can not but be extremely limited the result. Therefore, to spur in hidden cost's discovery and logistics' optimization is actuality. In this paper, as long as it is by logistics cost except empty driving if reverse logistics happens in distribution channel progressing, logistics reverse logistics' hidden cost through model that do minimization profit of logistics to look for plan that can do maximization try. Finally, is based on dual of distribution cost and profit of logistics and reverse logistics and achieves Pull, optimal system modeling that use Push system and gropes method of effective logistics cost.