• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1988.10a
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• pp.33-35
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• 1988

From the study of mechanism of electrical conduction of film which is made from Polyethylene Terephthalate at very high temperature which is larger than low electric field and glass transition point, we find that there is a extraordinary non ohmic region (I∝V$^n$, 0

• BMB Reports
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• v.49 no.1
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• pp.3-10
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• 2016

microRNAs (miRNAs) are key regulators of cell state transition and retention during stem cell proliferation and differentiation by post-transcriptionally downregulating hundreds of conserved target genes via seed-pairing in their 3' untranslated region. In embryonic and adult stem cells, dozens of miRNAs that elaborately control stem cell processes by modulating the transcriptomic context therein have been identified. Some miRNAs accelerate the change of cell state into progenitor cell lineages—such as myoblast, myeloid or lymphoid progenitors, and neuro precursor stem cells—and other miRNAs decelerate the change but induce proliferative activity, resulting in cell state retention. This cell state choice can be controlled by endogenously or exogenously changing miRNA levels or by including or excluding target sites. This control of miRNA-mediated gene regulation could improve our understanding of stem cell biology and facilitate their development as therapeutic tools. [BMB Reports 2016; 49(1): 3-10]

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2723-2728
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• 2008

The present study is numerically and experimentally performed to reveal the pumping characteristics of a helical-type molecular drag pump (HTDP) in the molecular transition flow region. In the experimental study, the pressures are measured simultaneously at the 5 positions along the helical channel of rotor under various conditions of outlet pressure and throughputs, and nitrogen is used as test gas. The outlet pressure is in the range of 26-533 Pa. As results, the local pressure changes are checked corresponding to the various outlet pressure and throughput of HTDP. In the numerical study, Navier-Stokes equations with slip boundary conditions are employed (Re< 1000, Kn< 0.1). The local pressure distribution and the pumping speed are calculated. The numerical results are compared with the experimental results. The numerically computed value agrees with the experimental data within an error of approximately 5%.

• Journal of Magnetics
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• v.8 no.2
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• pp.85-88
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• 2003

The magnetic and transport properties far single crystals of Ru-doped mono-layered manganites $La_{0.5}Sr_{1.5}-Mn_{1-x}Ru_xO_4$ (0$\leq$$\chi$$\leq$0.1) have been studied using neutron diffraction and magnetization measurements. Temperature dependent magnetization data reveal that with an increase in the Ru concentration the parent charge ordered antiferromagnetic state is gradually destroyed and new ferromagnetic phase evolves. In the low Ru-doped system spin glass behavior is apparent in low temperature region, which is confirmed by ac and do magnetization measurements. The competing magnetic interaction between Mn/Mn and Mn/Ru couples is the most likely cause of the spin glass transition.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.6
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• pp.369-378
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• 2016

The design spectrum for Korea, which is known to belong to an intra-plate region, is developed from the ground motion records of the earthquakes occurred in Korea and overseas intra-plate regions. The horizontal spectrum is defined as geometric mean spectrum, GMRotI50. From the statistical analysis of the geometric mean spectra, a mean plus one standard deviation spectrum in lognormal distribution is obtained. Regression analysis is performed on this curve to determine the shape of spectrum including transition periods. The developed design spectrum is valid for the estimation both spectral acceleration and displacement.

• Journal of Ocean Engineering and Technology
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• v.23 no.4
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• pp.1-5
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• 2009

A dilatometer was used to investigate the effect of cure conditions, mold types and the presence of filler in an epoxy system. These studies showed shrinkage in the cured epoxy when heating it through the glass transition temperature region. The magnitude of the shrinkage, related to stress build up in the epoxy during curing, was influenced by the processing conditions, filler presence and the nature of the mold used to contain the resin. Cure and cyclic cure at a lower temperature, prior to a post cure, decreased the magnitude of observed shrinkage. Cure shrinkage decreased with the number of cyclic cures. Post cured samples outside the mold led to less shrinkage compared with samples in the mold. Sample cured in a silicon mold represented less shrinkage than sample cured in an aluminum mold. Sample containing kaolin filler showed less shrinkage than unfilled sample.

• Journal of the Korean Ceramic Society
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• v.37 no.1
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• pp.63-69
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• 2000

Electrically-induced strain(S) and polarization(P) for Pb(Sc1/2Nb1/2)O3-PbTiO3(1-x)PSN-xPT) crystalline solutions were studied. From the compositional dependence of S and P we could observe two maximum values at x=0.10 and x=0.425. It is considered that PSNT10(x=0.10) composition is the structural phase boundary to indicate the variable order-disorder[VOD] region. PSNT(x=0.425) composition is the morphotropic phase boundary[MPB] to indicate the rhombohedral to tetragonal phase transition. Higher S (0.437%) and P (0.3974$\mu$C/$\textrm{cm}^2$) values were attained by the La substitution (5 wt%) at Pb site in the MPB composition of 57.5PSN-42.5PT.

• Proceedings of the KIEE Conference
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• summer
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• pp.899-901
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• 2004

This paper analyzes recording density according to the shape variation of Electric Probe writer, and present a shape design method for improving recording density in perpendicular electric recording device. The gradient of electric field has to be steep to improve recording density because transition region on the media becomes wider when recording. The optimum shape of electrode could be archived by using Response Surface Methodology and 2-Dimensional Finite Element Method.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.6
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• pp.678-682
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• 2004

Generally Bi-2223/Ag tapes have a broad S/N transition region and their sheath is a good electric conductor. In this study, the current distribution between superconductor and metal sheath in HTS tapes were investigated. AC with its peak value above 10 times $I_{c}$ was applied to HTS tapes for around 6 cycles and V-I characteristics were measured. Using the resistance of the sheath and V-I curves, the current distribution between superconductor and metal sheath was calculated. When 150 $A_{p}$ was applied, more than 2/3 of the current flows through superconductor. However, in the case of 304 $A_{p}$, most of the applied current came to flow through the metal sheath at the 6th cycle.e.e.e.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10b
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• pp.601-603
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• 2003

최근에 차량수의 증가로 인하여 교통량이 증가하고 그로 인하여 ITS(Intelligent Transport System)에 대한 관심이 증가하게 되었다. 그 중에서도 LPR system(License Plate Recognition system)은 ITS에서 중요한 역할을 한다. 본 논문에서는 차량의 번호를 인식하기 위해 선행되어야 하는 과정인 대상 차량의 번호판 영역을 추출하고 구성 숫자들을 분리하는 알고리즘을 제안한다. 이 알고리즘은 영상에서 차량의 번호판 영역을 찾는 부분과 번호판의 숫자를 분리하는 부분으로 구성이 되어 있다. 먼저 입력 영상에서 gradient를 구하게 된다. 구해진 gradient에서 차량의 구조와 transition의 횟수를 조사를 통해서 번호판 영역을 찾게 된다. 찾아진 번호판 영역에서 adaptive threshold를 적용하여 숫자들을 분리하게 된다. 실내 주차장 환경에서 촬영된 영상을 대상으로 실험을 수행하고 그 결과를 정리하였다.