• Journal of Yeungnam Medical Science
• /
• 제19권1호
• /
• pp.68-72
• /
• 2002

저자들은 신생아시기에서부터 담즙정체성을 나타낸 Dubin-Johnson 증후군 1예를 경험하였기에 문헌고찰과 함께 보고하는 바이다.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2008년도 추계학술대회A
• /
• pp.1633-1637
• /
• 2008

In this study, we developed 3D MLS-based variable-node elements for easy meshing. These elements should be derived from 2D MLS-based variable-node elements and would be utilized as key elements of easy meshing technique we proposed. Using developed 3D MLS-based variable-node elements, we demonstrated several examples having complex configuration compared with conventional meshing technique. Moreover, we compared with the stress results of our model and conventional one.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2008년도 추계학술대회A
• /
• pp.418-423
• /
• 2008

Among various sensitivity evaluation techniques, semi-analytical method is quite popular since this method is more advantageous than analytical method and global finite difference method. However, SAM reveals severe inaccuracy problem when relatively large rigid body motions are identified for individual elements. Such errors result from the numerical differentiation of the pseudo load vector calculated by the finite difference scheme. In the present study, the adjoint variable method combined with complex variable is proposed to obtain the shape and size sensitivity for structural optimization. The complex variable can present accurate results regardless of the perturbation size as well as easy to be implemented. Through a few numerical examples of the static problem for the structural sensitivity, the efficiency and reliability of the adjoint variable method combined with complex variable is demonstrated.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집A
• /
• pp.686-691
• /
• 2001

Structural optimization often require the evaluation of design sensitivities. The Semi Analytic method(SAM) is popular for shape optimization because this method has several advantages. But when relatively large rigid body motions are identified for individual elements, the SA method shows severe inaccuracy. In this paper, the improvement of design sensitivities corresponding to the rigid body mode is evaluated by exact differentiation of the rigid body modes. Moreover, the error of the SA method caused by numerical difference scheme is alleviated by using a series approximation for the sensitivity derivatives and considering the higher order terms.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
• /
• pp.304-309
• /
• 1998

In this paper, authors introduce an application of a nonlinear rotor flux observer, known under the name of ELO(extended Luenberger Observer), for direct rotor field oriented control(DRFOC) of induction motor. ELO requires no solution of nonlinear partial differential equation for its coordinate transformation and linearization used for the nonlinear observer design. Its simulation results concerned to different level of unknown variables of load torque and rotor resistance show high accuracy on rotor flux estimation in steady state.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
• /
• pp.714-716
• /
• 2002

Indium tin oxide (ITO) was used as the top anode of top emission inverted organic light emitting diodes (TEIOLEDs). TEIOLEDs were fabricated by deposition of an aluminum bottom cathode, an N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1, 1'-diphenyl-4, 4 1'-diamine (TPD) hole transport layer, a tris-8-hydroxyquinoline aluminum ($Alq_3$) emission layer, and an ITO top anode sequentially. ITO was deposited by r.f. magnetron sputtering without $O_2$ flow during the deposition. After the deposition, the deposited ITO layer was kept under oxygen atmosphere for the oxidation. The characteristics of the TEOILED were affected significantly by the post-deposition oxidation condition.

• 한국정보처리학회:학술대회논문집
• /
• 한국정보처리학회 2005년도 춘계학술발표대회
• /
• pp.289-292
• /
• 2005

임베디드 시스템은 하드웨어와 소프트웨어의 결합으로 이루어지며 일반적으로 임베디드 시스템을 구성하는 소프트웨어는 하드웨어로 제공되는 기능 개발 이후 시스템의 추가 기능을 제공하기 위해 개발되어 왔다. 임베디드 시스템의 개발 주기와 사용 주기는 상당히 짧아 시장성에 부합하는 임베디드 시스템을 개발하기 위한 체계적인 임베디드 시스템의 개발 지원 방법은 지속적으로 요청되고 있는 실정이다. 무엇보다도 개발 초기 단계에서부터 하드웨어와 소프트웨어 개발 요구 사항들이 분석되고 설계되어야 한다. 본 논문에서는 소프트웨어 관점에 기반해 임베디드 시스템의 설계 시 고려해야 할 요구 사항과 이를 지원하기 위한 방안에 대해 종합적으로 살펴보도록 한다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
• /
• pp.24-26
• /
• 2002

The recent emphasis on energy conservation demands an improvement of the efficiency of single-phase induction motors. To take the efficiency operation of the capacitor run single-phase induction motor with auxiliary and main winding, it is very important to select the capacitance value. This paper describes the theoretical analysis method of a single-phase induction motor which is based on the rotating field theory, using the method of symmetrical components. The optimal selection method of capacitance is proposed.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
• /
• pp.24-26
• /
• 1999

In this paper, the conceptual design and FE analysis results of salient pole type alternator under no load condition are described. The designed alternator's rating is 180kW, 3-phase, 4pole, 380/220V, 0.8pf, 60Hz. The conceptual design is described by the process of designing the armature, field, and obtaining some of equivalent circuit parameters. The comparison of FE analysis to the designed results of alternator's output voltage value shows a good agreement.

• 대한의용생체공학회:의공학회지
• /
• 제9권1호
• /
• pp.73-78
• /
• 1988

The polymer electrolyte complex hydrogels consisting of poly (methacrylic acid) and poly (4-vinylpyrridine) were formed and 5-flurouracil and pilocarpine drugs were loaded on their hydrogels. Cumulative 5-FU released from PEC hydrogel was affected by the degree of loading and release rate of 5-FU was followed by the monolithic type. Cumulative pilocarpine released from PEC hydrogel increased by ionic interaction between cationic pilocarpine and anionic PMA. Release rate showed the zero order after burst effect.