• 한국항공우주학회지
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• 제34권5호
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• pp.39-45
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• 2006

항공기의 가스터빈 엔진에서 축에 결함이 있을 경우에 대한 건전성 평가를 비파괴방법으로 접근했다. 로터의 축에 결함이 있을 경우에는 국지적으로 강성이 약화되어 임계속도가 달라진다. 결함이 있는 축의 순응도(compliance)행렬을 이용해서 각각의 결함의 위치와 깊이에 따른 임계속도를 구하고 이러한 결과들을 이용해 역 문제에 대한 자료를 구축함으로써 엔진 축의 건전성 평가를 수행하였다.

• 대한기계학회논문집A
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• 제31권4호
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• pp.441-450
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• 2007

In this study, a 3-DOF XYZ micro parallel manipulator utilizing compliance mechanism is developed and analyzed. In so doing, a matrix method is used to rapidly solve displacements of the designed kinematic structure, and then kinematic characteristics of the developed manipulator are analyzed. Finally, the design analysis of the kinematic characteristics by changing hinge thickness and structure to improve workspace and translation motion is performed to show that the performance of the developed manipulator is relatively superior to the other similar kind of manipulators.

• Journal of Pharmaceutical Investigation
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• 제41권5호
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• pp.263-272
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• 2011

Tablet dosage forms have been preferred over other formulations for the oral drug administration due to their low manufacturing costs and ease of administrations, especially controlled-release applications. Controlled-release tablets are oral dosage forms from which the active pharmaceutical ingredient (API) is released over an intended or extended period of time upon ingestion. This may allow a decrease in the dosing frequency and a reduction in peak plasma concentrations and hence improves patient compliance while reducing the risk of undesirable side effects. Conventional singlelayered matrix tablets have been extensively utilized to deliver APIs into the body. However, these conventional single-layered matrix tablets present suboptimal delivery properties, such as non-linear drug delivery profiles which may cause higher side effects. Recently, a multi-layered technology has been developed to overcome or eliminate the limitations of the singlelayered tablet with more flexibility. This technology can give a good opportunity in formulating new products and help pharmaceutical companies enhancing their life cycle management. In this review, a brief overview on the multi-layered tablets is given focusing on the various tablet designs, manufacturing issues and drug release profiles.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1992년도 가을 학술발표회 논문집
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• pp.162-167
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• 1992

The effects of railway vibration on nearby structures or equipment become severe with increasing the train speed and they may be also sufficiently intense to annoy the recipients. Often, the cost of the postcautionary measures may be more expensive than that of the precautionary ones to eliminate potential problems. This paper presents the Boundary Element approach for the evaluation of the dynamic response (in the form of the compliance matrix) of sleeper which can be used to predict the change of the vibration level.

• 대한의용생체공학회:의공학회지
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• 제6권1호
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• pp.13-18
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• 1985

A solution scheme for the squeeze film problem using the Newton-Raphson method with a tangential matrix is presented. The integration of elasticity equation is done with the aid of isoparametric elements and the film thickness under a sinusoidal load is obtained. A new squeeze-suction phenomenon which shoㅁvs the possibility oi maintaining fluid film under cyclic positive load conditions is observed for small load and Period and large compliance parameter cases. Thia could be an interesting result in applications like the viscous hydroplaning and the biological joints.

• Structural Engineering and Mechanics
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• 제20권2호
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• pp.143-160
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• 2005

Modal analysis of cracked cantilever composite beams, made of graphite-fibre reinforced polyamide, is studied. By using the finite element and component mode synthesis methods, a numeric model applicable to investigate the vibration of cracked composite beams is developed. In this new approach, from the crack section, the composite beam separated into two parts coupled by a flexibility matrix taking into account the interaction forces. These forces are derived from the fracture mechanics theory as the inverse of the compliance matrix calculated with the proper stress intensity factors and strain energy release rate expressions. Numerical results are obtained for modal analysis of composite beams with a transverse non-propagating open crack, addressing the effects of the location and depth of the crack, and the volume fraction and orientation of the fibre on the natural frequencies and mode shapes. By means of modal data, the position and dimension of the defect can be found. The results of the study confirmed that presented method is suitable for the vibration analysis of cracked cantilever composite beams. Present technique can be easily extended to composite plates and shells.

• 한국생산제조학회지
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• 제23권2호
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• pp.164-172
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• 2014

This paper presents a method for analyzing the stiffness of full and low DOF (degree of freedom) planar parallel manipulators with serially connected legs. The individual stiffness of each leg is obtained by applying reciprocal screws to the leg twist using passive joints and elastic elements consisting of actuators and links. Because the legs are connected in parallel, the manipulator stiffness is determined by summing the individual leg stiffness values. This method does not require the assumption that springs should be located along reciprocal screws and is applicable to a planar parallel manipulator with a generic or singular configuration. The stiffness values of three planar parallel manipulators with different DOFs are analyzed. The numerical results are confirmed using ADAMS S/W.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.658-662
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• 2001

Continuous fiber ceramic composites(CPCCs) having the advantages of ceramics resistance to heat, eroson can be applied in chemical reactors and engine. CFCCs has relatively high stiffness in spite of low weight. In particular, it exhibits greatly increased toughness, which serves to decrease its inherent damage characteristics of the brittle nature of monolithic ceramics. In this wort, tensile and flexural test for SCS6 fiber/ $Si_3N_4$ matrix composites were studied. An objective of this study is to obtain the basic quantities of mechanical properties for tension and flexural test and link these to the fracture resistance behavior. Then, we showed that wok of fracture concept was useful as a method for describing fracture restance behavior of CFCCs.

• Journal of Chest Surgery
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• 제43권6호
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• pp.565-575
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• 2010

배경: 이식편을 개발함에 있어서 숙주의 면역반응을 최소화하여 보다 더 오래 사용할 수 있게 하기위한 방법으로 무세포화에 대한 연구가 시행되고 있다. 저자들은 소 심낭의 무세포화의 과정에 효소제인 트립신 전처치가 물리역학적, 조직학적으로 미치는 영향에 대해 알아보고자 하였다. 대상 및 방법: 소 심낭편을 SDS와 Triton X-100 또는 N-lauroylsarcosinate와 Triton X-100으로 무세포화하는 것을 기본으로 한 군들과 0.1% 트립신/0.1% EDTA로 전처치를 추가한 군들에서 장력 검사를 실시하고, 생체 이식 후의 상태를 가정한 피로도 검사를 전후로 하여 투과도와 유순도는 검사하였고, 피로도 검사 전후로 조직학적인 변화를 광학현미경 및 전자현미경으로 관찰하였다. 결과: 트립신 처치를 추가한군과 아닌 군에서 기계적 장벽의 차이는 없었으나, 투과도와 유순도는 피로도검사 전과 후로 트립신 처치를 하지 않은 군에 비해 증가하였으며, 조직학적으로도 세포외 기질이 더 손상된 소견을 보였다. 걸론: 소 심낭의 무세포화에서 트립신 전처치는 세포외 기질의 손상을 유발하지만 기계적 장력에는 큰 영향을 미치지 않았으며, 피로도검사 전후 모두 투과도와 유순도를 증가시켰다. 무세포화과정에서 트립신과 같은 단백질 분해 효소제를 이용하기 위해서는 조직의 생체 물리적 손상을 최소화할 수 있는 다양한 방법을 조합한 연구가 더 필요하다.

• 전기학회논문지
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• 제62권8호
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• pp.1151-1156
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• 2013

In this study, to clearly establish the concept of a geometric modeling I apply for the concept of Pushbroom, limited to two-dimensional radiation Locator to provide a three-dimensional information purposes. Respect to the radiation scanner Pushbroom modeling techniques, geometric modeling method was presented introduced to extract three-dimensional information as long as the rotational component of the Gamma-Ray Linear Pushbroom Stereo System, introduced the two-dimensional and three-dimensional spatial information in the matching relation that can be induced. In addition, the pseudo-inverse matrix by using the conventional least-squares method, GCP(Ground Control Point) to demonstrate compliance by calculating the key parameters. Projection transformation matrix is calculated for obtaining three-dimensional information from two-dimensional information can be used as the primary relationship, and through the application of a radiation image matching technology will make it possible to extract three-dimensional information from two-dimensional X-ray imaging.