• Structural Engineering and Mechanics
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• v.10 no.1
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• pp.27-36
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• 2000

The Oktalok nodal connection system is an aesthetic and efficient system. It has been widely used throughout Australia. The paper will briefly introduce the concept and application of the Oktalok nodal system. The existing design method is based on the assumption that the joints are pin-ended, i.e., the rotational stiffness of the joints is zero. However the ultimate capacity of the frame may increase significantly depending on the rotational stiffness of the joints. Stiffness tests and finite element simulations were carried out to determine the rotational stiffness of the Oktalok joints. Column buckling tests and non-linear finite element analyses were performed to determine the member capacity of columns with semi-rigid end conditions. A simple formulae for the effective length factor of column buckling is derived based on the above experimental and theoretical investigations.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1073-1076
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• 2003

This paper shows the performance as a photodetector of InP/InGaAs HPT operated with a base bias and forntside optical injection through the emitter. InP/InGaAs HPT produced the high optical gain of about 16.2 where HPT is biased at Vc=1V, I$_{B}$=20$\mu$A with an input optical power of 2.4$\mu$W. And we examined that the optical gain of HPTs becomes larger when operating in 3-terminal configuration rather than 2-terminal with the floating base. The optical performance of InP/InGaAs HPT is an attractive to the PIN Photodetector for use in long wavelength optical receivers.s.

• ETRI Journal
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• v.29 no.4
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• pp.470-476
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• 2007

In this paper, a versatile three-input five-output universal capacitor-grounded voltage-mode filter is proposed. The circuit employs two differential voltage current conveyors as active elements together with two grounded capacitors and four resistors as passive elements. The proposed configuration can be used as either a single-input five-output or three-input two-output. Unlike the previously reported works, it can simultaneously realize five different generic filtering signals: lowpass, bandpass, highpass, bandreject, and allpass. It still maintains the following advantages: (i) the employment of all grounded capacitors, (ii) no need to employ inverting-type input signals, (iii) no need to impose component choice, (iv) orthogonal control of the resonance angular frequency ${\omega}_o$ and the quality factor Q, and (v) low active and passive sensitivity performances.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.401-411
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• 2003

Tube expanding process is for combining a heat-sink plate with hair-pins (Cu-tube) through plastic deformation. The two parts, i. e. , heat-sink plate and hair-pins are they components of a heat-exchanger for an air conditioner. This paper presents the analysis and dynamic modeling of a high-speed tube expander which integrates transfer of parts, fixing of parts, and tube expanding into one process. The 3-dimensional modeling of all the parts for the tube-expander was constructed using CATIA$\circledR$. then the CATIA$\circledR$ models are transferred into visuaINastran$\circledR$ to execute the 3-dimensional animation for checking prescribed cycle-time. The technique presented in this paper has been shown to be effective as a priori tool for verifying the design of a high-speed tube expander.

• Journal of the Korean Society of Costume
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• v.60 no.3
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• pp.1-9
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• 2010

The purpose of this study is to develop Blue-Jean Design for Ideal Body Shape. The final aim of Fashion design is looks beauty of people by optical illusion. This study is based on Gestalt therapy and, is blue jeans design using optical illusion of vertical line for ideal beauty body image. Optical illusion for blue-jean design effect to achieve the ideal body shape. We can accumulate the preceding study for modern clothing from design and the related optical illusion effects. Vertical line stitches have all the advantages especially in pants design. I design blue jeans using optical illusion theory. The results of this study are as follows: First, Vertical line helps that jean has the long body shape effectively. Second, Jeans which have two or more vertical lines is more effective than simple Jean in order to make slim body shape. Third, Appropriate position of horizontal lines can be effective to make long body shape. Fourth, Top stitch, pin-tuck and pleats can be applied to vertical or horizontal lines instead of cutting lines.

• Journal of Chest Surgery
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• v.27 no.4
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• pp.324-327
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• 1994

Resection and reconstruction of distal trachea or carina have posed tremendous technical challenges for surgeons. Successful outcome depends on thorough preoperative evaluation, careful anesthetic management,strict attention of surgical technique and postoperative care. We report a successful case of revision of tracheal stenosis using femoro-femoral bypass on a 13~year-old boy. The patient complained severe dyspnea about I month following right sleeve pneumonectomy. Preoperative CT scan and intraoperative bronchoscopy showed pin-point tracheal stenosis at a tracheo-bronchial anastomosis site about 1.2cm in length.At operation the lesion was severely adhesed and the lumen was nearly obstructed. The stenotic segment was resected and direct end-to-end anastomosis was done under femoro-femoral bypass for adequate oxygenation. The patient was discharged at postop. 16 days without specific complications and has continued to do well.

• Transactions of Materials Processing
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• v.8 no.3
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• pp.276-283
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• 1999

This study focuses on part quality and cycle times under gas-assisted injection molding (GIM) of box shape molded parts. The position of the gas channel was established near to parting line at the end of last locations to fill. Applied hot runner and valve gates, the gas was introduced directly into the mold cavity via gas pin. As GIM was applied, the conclusion reached as follows. I) The quality of appearance was improved by reducing sink marks and scratches of texture. ii) The reliability was improved by preventing warpages and reinforcing rigidity through optimum gas channel layout. iii) It is enable to use small size of injection molding machine step by step as GIM was accomplished low pressure and reduced clamp forces against CIM. iv) The productivity were improved by reducing cycle times.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.307-312
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• 1994

In this investigation the PFM(Pulse Frequency Modulation} will be used for optimizing PWM inverter pulse pattern. In traditional the pulse frequency of PWM is kept const. But modulated PWM's frequency in this study, the sinusoidal inverter's performance should be improved. The PWM pulsepatterns are definitely controlled so that the time-integral function of the voltage vectors in the space vector notation may show a circular locus. Further, performance index will be minimized because of minimizing distortion of output current. Finally, we will implement itusingsingle-chip microprocessor.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.10
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• pp.939-946
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• 2001

This study investigates the electrical and collection characteristics of a wide plate spacing electrostatic precipitator (ESP), using a pilot-scale one. Electrical operating characteristics and collection efficiency were measured for various shapes of discharge electrodes. The collection plate spacing ranged from 300 to 550 mm. Results of electrical characteristic and collection efficiency tests as a function of collection plate spacing, discharge electrode type, applied voltage, and particle diameter were obtained. Increasing the collection plate pitch and altering the corona electrode geometry was found to increase the collection efficiencies without increasing input power requirement. The best efficiency is achieved for the discharge electrode of twisted pin type.

• Proceedings of the Korean Society of Computer Information Conference
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• 2018.07a
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• pp.157-160
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• 2018

온라인 신분증명에는 공인인증서, I-PIN, 휴대전화 등이 사용된다. 서비스 제공자는 사용자의 신분을 증명한 후 사용자의 정보를 회원가입과 같은 절차를 통해 수집하고 저장한다. 이와 같이 중앙에서 관리하는 것은 관리적 측면의 편리성은 존재하지만 관리시스템 자체가 단일 실패 지점으로서의 위험성과 해킹 등으로 인한 개인정보 유출의 위험성이 상존한다. 최근 중앙관리의 한계를 급복하기 위해 분산 원장관리 기술인 블록체인 기술이 등장하였다. 블록체인 기술은 각각의 정보의 블록을 체인으로 연결하여 블록체인에 참여하는 각 노드에 의해 관리하는 분산관리 기술이다. 본 논문에서는 블록체인 기술을 기반으로 하는 온라인 신분증명 스킴을 제안한다. 블록체인을 기반으로 하기 때문에 개인의 정보를 중앙에서 관리할 필요가 없다. 또한 블록체인의 특성상 위변조로부터 안전하다는 장점이 있다. 마지막으로, 제안하는 방법에서 노드에 저장되는 개인정보는 암호화하는 방법을 사용하여 타인의 정보를 볼 수 없도록 하는 기밀성을 제공할 수 있어 노출에 대한 안전성을 제공한다.