• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.38-46
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• 2002

This paper evaluates crashworthiness of KHST carbodies under the SNCF accident scenario (collision against a movable rigid mass of 15 tons at 110 kph) and the scenario of train-to-train collision at 30 kph. The numerical results show that the final design of the KHST power-car doesn't have a good response on crashworthiness. So an improved design has been suggested for it. The improved design has shown good performances in the viewpoint of energy absorption and survival space at several numerical simulations, such as the accident collided against a deformable dump truck of 15 tons at 110 kph, the driver's dummy analysis, and the accident of train-to-train collision for the first three units at 30 kph.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2008년도 춘계학술발표대회 논문집
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• pp.290-294
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• 2008

Conversion of the building can be a core strategy to activate the urban regeneration. Especially in the decayed district, the conversion or retrofit of old building can be a core catalyst to stimulate the urban regeneration. Throughout the case study, a conversion from office to dwelling, there were figured out the design strategies to respond to spatial, functional requirements. The results are as follows ; 1) The main design strategy is to articulate the space by embedding the wall, mass in the rectangular space. 2) to respond to the small size of space, the flexible, movable wall system Is adopted. This gives the selectiveness to the use of space. 3) to secure the livability of interior space, the buffer zone, a terrace space, is fully utilized. This space acts as thermal buffer zone as well as a semi-interior space.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 추계학술대회 논문집
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• pp.545-552
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• 1998

A study on collision analysis of TGV-K using a 2-dimensional model is described to evaluate its crashworthiness. Two-dimensional analysis gives good information on overriding behaviour and impact forces applied to interconnecting devices such as side buffers, ball & socket joints, hooks, pins, and fingers. Since the headstock of TGV-K is not designed in a crashworthy point of view, its conceptual design fur KHST(Korean High Speed Train), under development, is suggested to improve crashworthiness. The suggested design, which adopts an energy absorber and a crashworthy headstock, is compared with the conventional headstock on dynamic behaviour to the vertical direction under the accident scenario of SNCF (collision at 110km/h against a movable rigid mass of 15 ton). It is concluded that the design modification make little difference in vertical motion. To evaluate validation of the 2-dimensional model, the results fur longitudinal motion is compared with those of 1-dimemsional one. It is found that the two results are in good agreements.

• Journal of Electrical Engineering and Technology
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• 제8권6호
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• pp.1320-1327
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• 2013

In this paper, two different electromagnetic energy harvesters using bulk micromachined silicon spiral springs and Polydimethylsiloxane (PDMS) packaging technique have been fabricated, characterized, and compared to generate electrical energy from ultra-low ambient vibrations under 0.3g. The proposed energy harvesters were comprised of a highly miniaturized Neodymium Iron Boron (NdFeB) magnet, silicon spiral spring, multi-turned copper coil, and PDMS housing in order to improve the electrical output powers and reduce their sizes/volumes. When an external vibration moves directly the magnet mounted as a seismic mass at the center of the spiral spring, the mechanical energy of the moving mass is transformed to electrical energy through the 183 turns of solenoid copper coils. The silicon spiral springs were applied to generate high electrical output power by maximizing the deflection of the movable mass at the low level vibrations. The fabricated energy harvesters using these two different spiral springs exhibited the resonant frequencies of 36Hz and 63Hz and the optimal load resistances of $99{\Omega}$ and $55{\Omega}$, respectively. In particular, the energy harvester using the spiral spring with two links exhibited much better linearity characteristics than the one with four links. It generated $29.02{\mu}W$ of output power and 107.3mV of load voltage at the vibration acceleration of 0.3g. It also exhibited power density and normalized power density of $48.37{\mu}W{\cdot}cm-3$ and $537.41{\mu}W{\cdot}cm-3{\cdot}g-2$, respectively. The total volume of the fabricated energy harvesters was $1cm{\times}1cm{\times}0.6cm$ (height).

• 대한골관절종양학회지
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• 제9권2호
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• pp.233-237
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• 2003

목적: 석회화 건막 섬유종은 소아 및 청소년층에서 수장부를 가장 많이 침범하는 양성이나 공격적 성향을 띈 섬유성 종양이다. 저자들은 최근에 15세 소년의 수부에 발생한 석회화 건막 섬유종의 치료를 경험하였기에 이를 문헌 고찰과 함께 보고하고자 한다. 증례: 15세 소년이 좌수의 소지구 부위에 재발하는 종물을 주소로 내원하였으며 이 소년은 7년전에 타 병원에서 국소 마취 하에 동일 부위에 발생한 종물을 제거한 기왕력을 가지고 있었다. 종물은 단단하였으며 압통이 있었다. 단순 방사선 촬영상에는 종물 내에 다소성으로 산재된 미세 석회 침착이 보였다. 수술 소견상 종물은 주변과 명확히 구분되지 않았으며 단단하고 옅은 회색빛의 석회화를 동반한 침습성의 결절성 형태를 보였으며 가이언 관내의 척골 신경과 척골 동맥이 바로 인접하고 있었다. 수술 후 제거한 종물을 현미경적으로 관찰한 결과 종물은 많은 석회 침착이 되어 있으면서 이형성 연골양 분화를 보이는 조직이 중간 중간에 섞여 있는 빽빽한 섬유 조직의 증식으로 이루어져 있었고 주변부는 명확히 경계 지어지지 않으며 분엽상을 보이고 있었다. 결론: 이 질환에 있어서 가장 바람직한 치료법은 기능적인 면과 주요 조직을 보존할 수 있는 한도내에서 광범위 절제를 시행하는 것이며 이렇게 치료하더라도 많게는 50 %이상의 재발율이 보고되고 있는 실정이다.

• 한국임상수의학회지
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• 제16권1호
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• pp.210-213
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• 1999

A 15 months old male pit bull terrier was shown submandibular swelling, which was extended from left submandibular area through mandibular symphysis to right submandibular area and toward around left neck. In history taking, recurrence of swelling was recorded after conservative surgical incision, drainage and dressing. Palpation revealed no pain and heating, partial flutuation and hardness. By paracentesis, it was showed blood-tinged tenacious exudate without bad-smelling. Left submandibular salivary gland was able to be movable freely and the size decreased to half of that of right submandibular salivary gland. It was diagnosed as cervical salivary mucocele. In operation, rostral portion of left sublingual salivary gland was observed to be damaged transversely, showed black color and leaked saliva. Submandibular gland and rostral portion of sublingual salivary gland were resected, after ligation of ducts of submandibular and sublingual salivary glands. At 15 days postoperation, serosanguineous exudate from operation wound was dramatically decreased and stable granulation tissue mass at this area was first palpated. At 39 days after operation, outline of left and right mandibular was appeared normal and skin tenderness of mandibular area was equal to that of the other body wall.

• 한국실내디자인학회논문집
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• 제14권1호
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• pp.28-36
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• 2005

The theme of modern architecture was various expression of dynamism and the flow of space. It was because that the space become the main theme of architecture since the late 19th century, and the space was changed from the 3rd dimension into the 4th dimensional space-time continuum. Though many avant-garde artists in the early 20th century did not understand the theory of relativity, they became conscious of the concept of space-time continuum, and tried to express the movement as the duration in time which Bergson defined. Many architects in the first machine age conceived the movement of architecture, and understand it as the dynamism of the mass and in the space. But especially, Sant'Elia and Hilberseimer expressed it as the flow of various force and vector In the metropolis as entire system. And Some architects conceived it as real movement of the building and expressed it as the rotary motion of building, movable partition and furniture, mobile prefabricated building. This study analyzed the expression of movement in architecture in the first machine age.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.945-950
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• 2001

Vacuum interrupters that is used in various switchgear components such as circuit breakers, distribution switches, contactors, etc. spreads the arc uniformly over the surface of the contacts. The electrode of vacuum interrupters is used sintered Cu-Cr material satisfied with good electrical and mechanical characteristics. Because the closing velocity is 1-3m/s, the deformation of the material of electrodes depends on the strain rate and the dynamic behavior of the sintered Cu-Cr material is a key to investigate the impact characteristics of the electrodes. The dynamic response of the material at the high strain-rate is obtained from the split Hopkinson pressure bar test using cylinder type specimens. Experimental results from both quasi-static and dynamic compressive tests with the split Hopkinson pressure bar apparatus are interpolated to construct the Johnson-Cook equation as the constitutive relation that should be applied to simulation of the dynamic behavior of electrodes. To evaluate impact characteristic of a vacuum interrupter, simulation is carried out with five parameters such as initial velocity, added mass of a movable electrode, wipe spring constant, initial offset of a wipe spring and virtual fixed spring constant.

• Water Engineering Research
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• 제2권3호
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• pp.179-185
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• 2001

The time consuming and expensive nature of experimental research on scouring processes caused by flowing water makes it attractive to develop numerical tools for the predication of the interaction of the fluid flow and the movable bed. In this paper the numerical simulation of scour by a wall jet is presented. The flow is assumed to be two-dimensional, and the alluvium is cohesionless. The solution process, repeated at each time step, involves simulation of a turbulent wall jet flow, solution of the convection-diffusion of sand concentration, and prediction of the bed deformation. For simulation of the jet flow, the governing equations for momentum, mass balance and turbulent parameters are solved by the finite volume method. The SIMPLE scheme with momentum interpolation is used for pressure correction. The convection-diffusion equation is solved for sediment concentration. A boundary condition for concentration at the bed, which takes into account the effect of bed-load, is implemented. The time rate of deposition and scour at the bed is obtained by solving the continuity equation for sediment. The shape and position of the scour hole and deposition of the bed material downstream of the hole appear realistic.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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• pp.404-407
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• 2003

In this paper, we have designed the humanoid robot's leg parts with 12 D.O.F. This robot uses ankle's joints to confirm stability of walking performance. It is less movable to use ankle's joints than to do upper body's balancing joints like IWR-III, which needs three parts of via points, support leg, swing leg and balancing joints. Instead, the proposed humanoid robot needs support leg and swing leg via points. ZMP(Zero Moment Point) is utilized to guarantee the stability of robot's walking. The humanoid robot uses the ankle's joints to compensate for IWR-III's balancing joints movement. Actually we concern about a motor performance when making a real humanoid robot. So a simulator is employed to know each joint torque of humanoid robot. This simulator needs D-H(Denavit-Hartenberg) parameters, robot's mass property and two parts of via points. The simulation results are robot's walking trajectories and each motor torque. Using the walking trajectories, we can see the robot's walking scene with 3D simulator. Before we develop the humanoid robot, simulation of the humanoid robot's walking performance is very helpful. And the torque data will be used to make humanoid's joint module.