• Journal of applied mathematics & informatics
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• 제29권5_6호
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• pp.1409-1420
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• 2011

In this paper we present an operational method for solving linear Volterra-Fredholm integral equations (VFIE). The method is con- structed based on three matrices with simple structures which lead to a simple and high accurate algorithm. We also present an error estimation and demonstrate accuracy of the method by numerical examples.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.816-819
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• 2008

A negative photoresist formulation was developed utilizing synthesized UV monomers containing imide linkage, photoinitiator, UV oligomer, and alkali developable polymer matrix. It was found that via-holes with good resolution, high transmittance and thermal resistance could be obtained by photolithographic process utilizing the negative-type photoresist formulations.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.430-430
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• 2000

This paper presents a new analytic approach using tetrahedrons to determine the forward kinematics of the 3-6-type Stewart platform. By using of the tetrahedral geometry, this approach has the advantage of greatly reducing the complexity of formulation and the computational burden required by the conventional methods which have been solved the forward kinematics with three unknown angles. As a result, this approach allows a significant abbreviation in the formulations and provides an easier means of obtaining the solutions. The proposed method is well verified through a series of numerical simulation.

• 오토저널
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• 제13권3호
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• pp.58-67
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• 1991

A theory of continuum damage mechanics based on the theory of materials of type N was developed and its nonlinear finite element approximation and numerical simulation was carried out. To solve the finite elastoplasticity problems, reasonable kinematics of large deformed solids was introduced and constitutive relations based on the theory of materials of type-N were derived. These highly nonlinear equations were reduced to the incremental weak formulation and approximated by the theory of nonlinear finite element method. Two types of problems, compression moulding problem and pure bending problem, were solved for aluminum 2024.

• 한국식품과학회지
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• 제25권5호
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• pp.475-480
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• 1993

본 연구는 육류등급제 시행에 따라 유화형 소시지 제조시 원료육의 일반성분과 기능성 규명을 통해서 최소사격배합에 입력자료로서 사용될 원료육의 결착지수를 국내 실정에 맞도록 추정하고자 실시하였다. 각 원료육의 일반성분, 기능성 및 육색소 함량은 축종별 부위별로 다양한 수치를 보였으며 원료육의 결착력(cohesiveness)과 높은 상관산계를 갖는 것이 많았다. 특히 수분, 단백질함량과는 정의 상관관계를, 지방함량과는 부의 상관관계를 나타냄으로써 단지 일반성분 분석치만으로도 원료육의 결착성 추정을 위한 회귀식 산출이 가능하였다. 따라서 분석기기가 갖추어지지 않은 공장현장에서도 최소가격배합에 필요한 결착지수의 추정이 가능하며 기존의 결착지수가 밝혀지지 않은 원료육의 결착지수 추정도 가능하였다.

• Applied Biological Chemistry
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• 제47권3호
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• pp.325-331
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• 2004

왕겨 분말을 가연성 담체로 첨가하여 분상, 과립상 및 봉상의 fenarimol 훈연제를 제제하고 제형이 훈연제의 연소성에 미치는 영향을 조사하였다. 가연성 담체로 목분을 사용한 목분 훈연제의 연소성을 조사하고 왕겨 훈연제와 비교하였다. 왕겨 분말을 가연성 담체로 한 fenarimol 훈연제(3%)는 분말, 과립 및 막대 모양으로 성형할 수 있었으며, 염소산나트륨 첨가비가 11% 이상일 때 모두 연속적으로 연소하였다. 형상과 무관하게 모두 염소산나트륨 첨가비가 13%인 훈연제의 훈연율이 가장 높았으며, 분상 훈연제(64.5%) < 과립훈연제(78.4%) < 봉상 훈연제(90.9%) 순으로 훈연율이 증가하였다. 봉상 훈연제는 과립훈연제보다 점화가 특히 용이하고 강도와 훈연율이 우수하였다. 목분을 가연성 담체로 사용한 훈연제는 방염 성분을 함유하여 연소 시간이 매우 길어지는 특성이 있어서 훈연제보다 서서히 연소하는 훈증제용 담체로 더 적합하였다.

• 대한기계학회논문집
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• 제19권4호
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• pp.1023-1032
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• 1995

The multiple cooperating robot system plays an important role in the research of modern manufacturing system as the emphasis of production automation is more on the side of flexibility than before. While the kinematic and dynamic analysis of a single robot is performed as an open-loop chain, the dynamic formulation of robot in a multiple cooperating robot system differs from that of a single robot when the multiple cooperating robots form a closed kinematic chain holding an object simultaneously. The object may be any type from a rigid body to a multi-joint linkage. The mobility of the system depends on the kinematic configuration of the closed kinematic chain formed by robots and object, which also decides the number of independent input parameters. Since the mobility is not the same as the number of robot joints, proper constraint condition is sought. The constraints may be such that : the number of active robot joints is kept the same as mobility, all robot joints are active and have interrelations between each joint forces/torques, two robots have master-slave relation, or so on. The dynamic formulation of system is obtained. The formulation is based on recursive dual-number screw-calculus Newton-Eulerian approach which has been used for single robot analysis. This new scheme is recursive and compact symbolically and may facilitate the consideration of the object in real time.

• 한국해양공학회지
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• 제16권2호
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• pp.53-59
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• 2002

This paper shows the experimental results controlling the height of surface and back bead in GMAW by analyzing the unexpected gaps between base metals produced in welding and by controlling welding velocity due to the variation of the gap between base metals in thin-plate welding. The back bead behavior and burn-through in I-type butt joint $CO_2$ welding of thin mild steel are analyzed in the views of short circuit time ratio and short circuit frequency. It is shown through experimental consideration that the short circuit time ratio method is more reasonable than the short circuit frequency method in analyzing the formulation of back bead under changing the gap between base metals. Based on the these results, welding manipulator is designed so as to satisfy the bead height control in real time by measuring the short circuit time ratio. To show the effectiveness of the developed bead formulation control system, the experiment is implemented under two welding conditions such as increasing gap from 0mm to 0.8mm and gradually increasing gap from 0mm to 1.2mm. The experimental results show that the bead formulation can be controlled uniformly in spite of the variation of the gap between base metals.

• Structural Engineering and Mechanics
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• 제85권2호
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• pp.147-161
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• 2023

Based on the ideas of variational differential quadrature (VDQ) and finite element method (FEM), a numerical approach named as VDQFEM is applied herein to study the large deformations of plate-type structures under static loading with arbitrary shape hole made of functionally graded graphene platelet-reinforced composite (FG-GPLRC) in the context of higher-order shear deformation theory (HSDT). The material properties of composite are approximated based upon the modified Halpin-Tsai model and rule of mixture. Furthermore, various FG distribution patterns are considered along the thickness direction of plate for GPLs. Using novel vector/matrix relations, the governing equations are derived through a variational approach. The matricized formulation can be efficiently employed in the coding process of numerical methods. In VDQFEM, the space domain of structure is first transformed into a number of finite elements. Then, the VDQ discretization technique is implemented within each element. As the last step, the assemblage procedure is performed to derive the set of governing equations which is solved via the pseudo arc-length continuation algorithm. Also, since HSDT is used herein, the mixed formulation approach is proposed to accommodate the continuity of first-order derivatives on the common boundaries of elements. Rectangular and circular plates under various boundary conditions with circular/rectangular/elliptical cutout are selected to generate the numerical results. In the numerical examples, the effects of geometrical properties and reinforcement with GPL on the nonlinear maximum deflection-transverse load amplitude curve are studied.