• 한국초지조사료학회지
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• 제29권3호
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• pp.187-196
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• 2009

청보리, 밀, 호밀, 트리티케일, 귀리 등 5종의 총체맥류에 대하여 중부지역에서 답리작 재배시 월동 후인 3월 15일 부터 6월 15일까지 10일 간격으로 10회에 걸쳐 예취한 후 각 작물별 예취시기에 따른 사료가치를 비교하였다. ADF 함량은 5종의 총체맥류 모두 월동 후 증가하다가 각 작물별로 최고점에 도달한 후 성숙이 진행됨에 따라 감소되는 2차원적인 경향을 보였고, NDF 함량은 월동 후 점진적으로 증가하다가 대체로 어느 일정시기 이후에는 정체되거나 다소 감소되는 경향을 보였으며, 조단백질 함량은 잎이 풍부한 월동 직후에 높았다가 생육단계가 진행됨에 따라 점진적으로 감소되는 경향을 보였다. 가소화건물(DDM) 함량은 총체맥류 5종 모두 월동 후 생육이 진전될수록 낮아지다가 출수기 이후 종실이 충실해짐에 따라 다시 증가되는 경향을 보였고, 상대사료가치(RFV)는 월동 후 잎이 풍부한 생육초기에 높았다가 생육이 진전됨에 따라 감소되었으며, 출수기 이후에 종실이 충실해지면서 다시 증가되는 경향을 보였다. 맥종별로 보면 청보리인 영양보리는 다른 총체맥류에 비하여 출수기 이후 ADF와 NDF 함량이 낮았고, 가소화건물 함량과 상대사료가치(RFV)가 높았다. 금강밀은 다른 총체맥류에 비하여 단백질 함량이 높았고, 출수기 이후 가소화건물 함량과 상대사료 가치가 곡우호밀, 신영트리티케일, 삼한귀리에 비하여 상대적으로 높았다. 곡우호밀은 다른 총체맥류에 비하여 내한성과 내재해성이 강하지만 월동 후 성숙기 까지 ADF와 NDF 함량이 높고, DDM 함량과 상대사료가치 (RFV)가 낮은 조사료 작물에 해당하였다. 신영트리티케일은 영양보리 또는 금강밀과 곡우호밀의 중간적인 특성을 보였으며, 생육후기로 갈수록 가소화건물 수량이 직선적으로 증가하였다. 삼한귀리는 출수 전까지 ADF와 NDF 함량이 낮고 단백질이 풍부하였지만, 출수 후 성숙이 진행될수록 다른 총체맥류에 비하여 변화가 적었다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2009년도 정기 학술대회
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• pp.534-535
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• 2009

This paper deals with BEM analysis of transient elastodynamic problems using domain decomposition method and particular integrals. The particular method is used to approximate the acceleration term in the governing equation. The domain decomposition method is examined to consider multi-region problems. The domain of the original problem is subdivided into sub-regions, which are modeled by the particular integral BEM. The iterative coupling employing Schwarz algorithm is used for the successive update of the interface boundary conditions until convergence is achieved. The numerical results, compared with those by ABAQUS, demonstrate the validity of the present formulation.

• Carbon letters
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• 제14권1호
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• pp.58-61
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• 2013

In this work, the effect of catalysts on the mechanical properties of carbon fibers-reinforced epoxy matrix composites cured by cationic latent thermal catalysts, i.e., N-benzylpyrazinium hexafluoroantimonate (BPH) was studied. Differential scanning calorimetry was executed for thermal characterization of the epoxy matrix system. Mechanical interfacial properties of the composites were studied by interlaminar shear strength (ILSS), critical stress intensity factor ($K_{IC}$), and specific fracture energy ($G_{IC}$). As a result, the conversion of neat epoxy matrix cured by BPH was higher than that of one cured by diaminodiphenyl methane (DDM). The ILSS, $K_{IC}$, $G_{IC}$, and impact strength of the composites cured by BPH were also superior to those of the composites cured by DDM. This was probably the consequence of the effect of the substituted benzene group of BPH catalyst, resulting in an increase in the cross-link density and structural stability of the composites studied.

• Structural Engineering and Mechanics
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• 제32권1호
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• pp.37-53
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• 2009

In this paper the problem of calculating the probability that the responses of a wind-excited structure exceed specified thresholds within a given time interval is considered. The failure domain of the problem can be expressed as a union of elementary failure domains whose boundaries are of quadratic form. The Domain Decomposition Method (DDM) is employed, after being appropriately extended, to solve this problem. The probability estimate of the overall failure domain is given by the sum of the probabilities of the elementary failure domains multiplied by a reduction factor accounting for the overlapping degree of the different elementary failure domains. The DDM is extended with the help of Line Sampling (LS), from its original presentation where the boundary of the elementary failure domains are of linear form, to the current case involving quadratic elementary failure domains. An example involving an along-wind excited steel building shows the accuracy and efficiency of the proposed methodology as compared with that obtained using standard Monte Carlo simulations (MCS).

• Computers and Concrete
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• 제6권2호
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• pp.95-108
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• 2009

In the current research, a displacement-based seismic design scheme to retrofit reinforced concrete columns using FRP composite materials has been proposed. An accurate prediction for the nonlinear flexural analysis of FRP jacketed concrete members has been presented under multiaxial constitutive laws of concrete and composite materials. Through modification of the displacement coefficient method (DCM) and the direct displacement-based design method (DDM) of reinforced concrete structures, two algorithms for a performance-based seismic retrofit design of reinforced concrete columns with a FRP jacket have been newly introduced. From applications to retrofit design it is known that two methods are easy to apply in retrofit design and the DCM procedure underestimates the target displacement to compare with the DDM procedure.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제38권6호
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• pp.321-325
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• 2012

Collagen is widely used for regenerative therapy and pharmaceutical applications as one of the most useful scaffolds. Collagen is the most abundant protein in vertebrates and the natural substrate of various types of animal cells. Bone and dentin are mineralized tissues and almost similar in chemical components. They consist of collagen (18%), non-collagenous proteins (2%), hydroxyapatite (70%) and body fluid (10%) in weight volume. Pepsin-digested, type I collagen (atelocollagen) and heat-denatured collagen (gelatin) are basic collagenous materials for medical use. Demineralized dentin matrix (DDM) and demineralized bone matrix (DBM) belong to acid-insoluble group, and vital tooth-derived DDM is a unique dentin material including cementum and growth factors. In this review, collagen-based materials will be introduced and discussed for bone regenerative surgery.

• Elastomers and Composites
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• 제32권3호
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• pp.179-185
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• 1997

In solution and melting state, SiOD prepolymer was prepared by cured excess DDM with epoxy-terminated siloxane oligomers to control phase separation when DGEBA was blended with PDMS. DGEBA/SiOD prepolymer was also cured at $150^{\circ}C$ for 3hrs. Mechanical and thermal properties of the cured prepolymer specimen were investigated. DGEBA/SiOD60 specimen blended SiOD prepolymer had the best flexural strength, modulus and impact strength. To show crack-formation procedure to morphology, DGEBA/DDM neat specimen was flowed homogeneously in direction of crack energy, whereas DGEBA/SiOD$(30{\sim}60)$ specimen showed heterogeneously dispersed particles and scattered domain of crack energy, but DGEBA/SiOT specimen showed homogeneous phase.

• 한국산업융합학회 논문집
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• 제4권3호
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• pp.329-337
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• 2001

This simulator is developed for the analysis of a MOSFET based on Thermally Coupled Energy Transport Model(TCETM). The simulator has the ability to calculate not only stationary characteristics but also non - stationary characteristics of a MOSFET. It solves basic semiconductor devices equations including Possion equation, current continuity equations for electrons and holes, energy balance equation for electrons and heat flow equation, using finite difference method. The conventional semiconductor device simulation technique, based on the Drift-Diffusion Model (DDM), neglects the thermal and other energy-related properties of a miniaturized device. I, therefore, developed a simulator based on the Thermally Coupled Energy Transport Model (TCETM) which treats not only steady-state but also transient phenomena of such a small-size MOSFET. In particular, the present paper investigates the breakdown characteristics in transient conditions. As a result, we found that the breakdown voltage has been largely underestimated by the DDM in transient conditions.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2003년도 춘계학술대회논문집
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• pp.179-184
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• 2003

HLA-RTI is middleware for the distribute simulation that developed in the US Department of Defense. This provides fast accomplishment speed and reliability than distribute simulation Middleware by transfer. However, DDM(Data Distribution Management) service is used as data filtering technology in the existing HLA-RTI. As for this, the problem that network traffic increases in data exchange between the mobility simulation objects is generated. it proposes applying agent technology to the mobility simulation object in order to solve these problems in this paper in this. And this paper applies that to practical simulation and analyzes performance between each data filtering technology with comparison.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.1039-1044
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• 2005

The Objective of advanced EMU Project is development of new technologies, that can resolve the system problems of conventional EMU, for reducing vehicle maintenance, improving passenger's service using IT and providing environmental friendly. As a concept of advanced EMU, We will develop the DDM with individual driving wheel for reducing of maintenance cost and full-electric braking system without pneumatic braking, and a new bogie for loadable DDM, and pre-diagnosis system which informs possible system error, and decentralization of vehicle control. To improve transport reliability, and energy storage system for saving energy, and fallen passenger detection system for improving passenger's safety at the platform.