• Journal of the Korean Society for Railway
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• v.11 no.1
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• pp.13-18
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• 2008

In this study, unsteady wind pressure analyses on platform screen door (PSD) have been conducted considering the flow intereference effects between the moving train and the configuration of subway station. The major role of PSD prevents passenger accidents, wind pressure, polluted dust and noise when the train is entering the station platform. Computational fluid dynamic method with moving gird algorithm has been adopted to accurately predict unsteady pressure levels exerted on the PSD. Closed and open type station configuration are considered. Also, wind pressure levels for passing and stopping drive motion of the entering train are presented and practically compared each other.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.2
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• pp.178-185
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• 2002

This paper describes the implementation of three-phase three-wire active power filter system with a instantaneous PSD for distorted and unbalanced power conditions. The positive sequence voltage of the distorted and the unbalanced power system is calculated by the Instantaneous PSD, and phase transformation matrix of the instantaneous power theory is achieved with detected positive sequence voltage. Finally, the proposed method is experimented and tested under unbalanced nonlinear load as well as unbalanced /distorted condition in power system.

• Journal of the Korean Society of Propulsion Engineers
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• v.9 no.2
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• pp.32-39
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• 2005

The effectiveness of the pogo suppression device (PSD) on the response of the piping system simulating the fuel (or oxidizer) supply lines of the rocket engines was investigated. The system response defined as the ratio of the flow rate to the pressure in the main tube was obtained for various PSD gas volumes $((0\~2)\times10^{-3}m^3)$ and three different baffle hole diameters (5, 50, 115mm). Existence of a gas volume in the PSD reduced the system resonance frequency. With a larger gas volume, the resonance frequency became lower, but only slightly, while the fluctuations of the main tube pressure and the flow rate damped down considerably. The resonance frequency decreased with the increase of the PSD inlet restriction (or the decrease of the baffle hole diameter), though slightly. However, with a larger inlet restriction, the PSD pressure wave showed a delayed response with the smaller amplitude compared to the pressure variation in the main tube.

• Journal of Digital Convergence
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• v.16 no.7
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• pp.381-391
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• 2018

The purpose of this research is to propose a new method of PSD(Platform Screen Door) ads using animated image for efficiency, based on the theoretical background that moving objects have a stronger visual attractiveness effect than static objects. For this, we analyze the relationship between the screen door and the train, then derive the positional and visual elements which help to create efficient animated images. Based on this analysis, we made an example and applied into 3D program to confirm the implementation process of the animated PSD ads. As the result, the research shows that it is possible to produce a new type of PSD ads that can show dynamic visual effects and can give diversity to the PSD advertising media through the combination of the images using time difference.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2001.11a
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• pp.55-56
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• 2001

지난 수년간 유럽을 중심으로 Carbonate의 PSD (Particle Size Distribution)가 도공지 의 백색도, 불투명도, Coverage등에 미치는 영향에 대하여 많은 연구가 진행되어 왔다. 현재 국내의 Coating Pigment System 역시 Carbonate 위주로 구성되어 있으나, 입자 분포에 따른 실증적 연구가 선진국에 비하여 부족한 상태이다. 본 연구는 최근 유럽에서 사용 중인 Narrow PSD Carbonate가 도공지 품질에 미치는 영향을 검토한 것으로서, 특히 Multiple Coating에서의 도공층 구조변화와 그에 따른 백지물성 및 인쇄적성의 변화를 연구한 것이다. 실험의 Case는 Broad PSD CaC03와 Narrow PSD CaC03를 비 교하였 다 .. Color F Formulation은 Pre Color에서 #1 Clay 30 p따t와 각각 CaC03 70 p따t를 사용하였다. 그리고 바인더와 첨가제는 동일하게 사용하였다 .. Top color Formulation 또한 동일하 게 사용하였다. 코팅방식은 speed 450rrνmin, pre rod coating, top blade coating 방식 으로 CLC (Cy lindrical Laboratory Coater)를 사용하여 코팅하였다. 백지품질은 백색도, 평활도 ,광택도, 거칠음도, Bum Out Test와 Coverage( SEM 사 진 Z -direction) 등을 측정하였다. 인쇄품질은 인쇄 광택도, 인쇄 Picking strength와 2 도 인쇄 농도를 측정하였다. 백색도는 Narrow PSD CaC03를 사용한 것이 Broad PSD CaC03를 사용한 것 대비 약1% 우수하였다. 이것은 Narrow PSD CaC03를 사용한 것이 filter cake이 많이 open 되 어 있어 dewatering이 빠르고, Wet void volume이 증가되 어 부동화점 의 농도가 낮 아져 원지 층으로 침 투되 는 pigment가 작고 표층에 잔류하는 pigment와 void volume의 증가로 인해 기공층이 증가한 것으로 판단된다. 그리고, 백지광택도, 거칠음도 등 또한 Narrow PSD CaC03를 사용한 것이 우수하였 다. 이는 Pre color에서 coverage의 개선으로 top color층의 도공량 uniformity가 개선 된 이유라고 생각한다. 그러나 인쇄품질은 백지와 비교하여 차이가 없었다. 이것은 top 칼라 Formulation이 동일하고, 인쇄시 잉크흡수 거동은 top color 층에 주로 영향을 받기 때문이라고 판단 된다. 향후에는 인쇄품질의 향상을 위하여 Case 2의 CaC03 100% 사용가능성 및 Pre Color 는 Case 2로 고정하고, Top칼라를 변경하는 방법을 또한 생각할 필요가 있다고 판단된다.

• Journal of Life Science
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• v.7 no.3
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• pp.198-204
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• 1997

The signal transduction through tyrosine kinases play important roles in neuronal development and synaptic regulation. We carried out immunoblot analyses to study tyrosine=phosphorylated proteins in the rat cerebellar postsynaptic density (PSD), a protein-rich cytoskeletal specialization underlying beneath the postsynaptic membrane. The overall protein composition of cerebellar PSD fractions was similar to that of the forebrain’s and only a few bands were different in Coomassie stain. Immunoblot analyses with phosphtyrosine-specific antiboy (4G10) showed that there are many more tyrosine-phosphorylated proteins in the cerebellar PSD than in the forebrain PSD. Interestiingly, a major phosphotyrosine signals in cerebellar PSD fractions was associated with a 50 kD molecular size, named as PSD-50. Migration of PSD-50 coincided with that of $\alpha$CaMKII and remained in the pellet fraction after N-octylglucoside extraction. These results indicate that tyrosine phosphorylation is important in cerebellar synaptic regulation and that the PSD-50 may be same as $\alpha$CaMKIIor a new protein which is a major substrate of tyrosine kinase.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.6
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• pp.668-672
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• 2005

In this paper, a distance measuring system using a PSD sensor in proposed, which in suitable for low-cost localization sensor of a mobile robot. Because the distance-voltage output of PSD sensor has a non-linear property, the linearizing function is proposed through the experimental characteristics of the sensor. And the characteristics are tested and the distance-voltage data are measured in various colors and materials of object. The parameters of the proposed function are extracted by using the measured data. Finally, the performance and the accuracy of the developed system are verified according to the comparison of the distance by the proposed function with the real distance.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.10a
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• pp.121-125
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• 2004

The effectiveness of the pogo suppression device (PSD) installed at the piping system simulating the fuel supply lines of the rocket engines was investigated. The system response defined as the ratio of the flow rate to the pressure in the main tube was obtained for various PSD gas volumes $(0,\;0.5,\;1,\;2\times10^{-6}\;m^3)$. Existence of a gas volume in the PSD reduced the system resonance frequency. With a larger gas volume, the resonance frequency became lower, but only slightly, though the fluctuations of the main tube pressure and the flow rate damped down considerably

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.8
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• pp.1951-1962
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• 1993

The creation process of a typical machined surface is treated here as a dynamic system. An investigation is carried out to establish a relationship between the characteristics of cutting force fluctuations that cause vibration response of the tool-workpiece system and the formation of surface in face cutting by sintered carbide cutting tool. Cutting force is measured and analyzed in frequency domain. The power spectral densities of cutting force give a useful information in surface generation and it can be used to find out the control factor of surface roughness. The terms, PSD ratio & Normalized spindle frequency PSD, are defined and when the value of power in spindle frequency is absolutely little but relatively large, it is obtained high accuracy surface roughness. The aim of this research is to find surface profile by measured and analyzed cutting force signals. The simulation of surface generation gives the comprechension of its mechanism and help to predict and control the surface quality. In this study, it is suggested what informations about surface generation can be acquired from the cuttuing force signal and an way of generating a better surface.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.299-300
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• 2011