• Journal of Korea Multimedia Society
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• v.15 no.11
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• pp.1369-1376
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• 2012

In this paper, we propose 2D industrial image registration method for the detection of defects. Proposed method performs preprocessing to smooth the original image with the preservation of the edge for the robust registration against general noise. Then, x-direction gradient magnitude image and corresponding binary image are generated. Density analysis around neighborhood regions per pixel are performed to generate feature image for preventing mis-registration due to moire-like patterns, which frequently happen in industrial images. Finally, 2D image registration based on phase correlation between feature images is performed to calculate translational parameters to align two images rapidly and optimally. Experimental results showed that the registration accuracy of proposed method for the real industrial images was 100% and our method was about twenty times faster than the previous method. Our fast and accurate method could be used for the real industrial applications.

• Journal of Navigation and Port Research
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• v.32 no.8
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• pp.611-619
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• 2008

The Ministry of Land, Transport and Maritime Affairs is working on the construction of Nationwide DGPS(NDGPS) with connection to Maritime DGPS Reference Stations and if Chun-cheon Reference Station is to be completed in 2008, DGPS positioning information is available in the whole area of Republic of Korea. Therefore to promote the usage of DGPS surveying information, we measured and panalyzed the accuracy of DGPS. In real-time DGPS positioning accuracy were 0.42m of planar Root Mean Square(RMS) error in static survey and 0.48m of planar RMS error in dynamic survey. We went abreast with RTK comparison measurement. According to these results. DGPS positioning information cannot be applied directly to the GIS construction field, but GIS application fields, requiring the real-time positioning information. can take advantage of it in variable cases.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.6A
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• pp.577-586
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• 2011

Modem digital communication systems are required to use forward error correction (FEC) codes to combat inevitable channel impairment. Turbo codes or low density parity check (LDPC) codes, using iterative decoding with soft decision detection (SDD) information, are the most common examples. The excellent performance of these codes should be conditioned on accurate estimation of soft decision detection information. In order to use FEC codes with iterative decoding for Multi-Input Multi-Output (MIMO) system, reliable soft decision channel gain should be provided. In this paper, we investigate efficient SDD methods for turbo-coded MIMO system, and derive the corresponding formulas of SDD for various MIMO detection schemes. We present simulation results of the derived SDD schemes for turbo-coded MIMO systems, and show that the presented results almost approximate to maximum likelihood detection performance with much less computational load.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.976-979
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• 2002

A focusing grating coupler (FGC) was not fabricated by the 'Continuous Path Control' writing strategy but by an electron-beam lithography system of more general exposure mode, which matches not only the address grid with the grating period but also an integer multiple of the address grid resolution (5 nm), To more simplify the fabrication, we are able to reduce a process step without large decrease of pattern quality by excluding a conducting material or layer such as metal (Al, Cr, Au), which are deposited on top or bottom of an e-beam resist to prevent charge build-up during e-beam exposure. A grating pitch period and an aperture feature size of the FGC designed and fabricated by e-beam lithography and reactive ion etching were ranged over 384.3 nm to 448.2 nm, and $0.5{\times}0.5mm^2$ area, respectively, This fabrication method presented will reduce processing time and improve the grating quality by means of a consideration of the address grid resolpution, grating direction, pitch size and shapes when exposing. Here our investigations concentrate on the design and efficient fabrication results of the FGC for coupling from slab waveguide to a spot in free space.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.2
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• pp.247-251
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• 2010

Using SCM in storage systems introduce new potentials for improving I/O performance and reliability. In this paper, we study the use of SCM as a buffer cache that guarantees transactional unit writes. Our proposed method can improve storage system reliability and performance at the same time and can recover the storage system immediately upon a system crash. The Proposed method is based on the LINUX JBD(Journaling Block Device), thus reliability is equivalent to JBD. In our experiments, the file system that adopts our method shows better I/O performance even while guaranteeing high reliability and shows fast file system recovery time (about 0.2 seconds).

• Korean Journal of Cognitive Science
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• v.24 no.1
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• pp.25-47
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• 2013

We conducted a psycholinguistic experiment in which participants orally produced sentences using a subject, a dative object, an accusative object, and a verb, provided just before the production. Results of the experiment are twofold: (i) Korean speakers basically produce the dative object earlier than the accusative one if the lengths of the objects are identical. (ii) If there is a length difference between the two objects, though, the longer one strongly tends to be placed before the shorter one, overriding the preference for 'dative-accusative' order. This 'long before short' preference which is generally observed in head-final languages appears to reflect the underlying tendency of the processing mechanism to put the heads of arguments and the predicate as closely as possible, thereby minimizing the cost for the processing of verb-argument structure.

• Journal of Labour Economics
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• v.26 no.3
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• pp.115-147
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• 2003

This paper scrutinizes the robustness of the profit-sharing findings first employing an original panel data on the Employee Welfare Fund over the period from 1992 to 2000. In examining the effects of profit-sharing schemes on labor productivity, it controls for simultaneity among profit-sharing, production factors, and productivity using both the two-stage least squares procedure and the lagged variable method. The empirical results show that an increase in firm's contribution to the Employee Welfare Fund is associated with capital-embodied and disembodied productivity enhancement, which is both statistically and economically highly significant. The empirical results are in contrast with predictions of both agency and transaction cost theories, and they imply that more tax benefits and financial incentives for expansion of the Employee Welfare Fund should be required to get productivity gains.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2002.05a
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• pp.12-12
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• 2002

hexagonal Boron Nitride (hBN), rhombohedral Boron Nitride (rBN)과 고밀도의 wurzitic Boron N Nitride (wBN), cubic Boron Nitride (cBN) 등의 다양한 상을 갖는 Boron nitride는 그 결정구조에 따라 저밀도, 고밀도 박막으로 분류되며 이중 hBN과 rBN은 층간 결합이 약한 $sp^2$ 결합특성을 가지고, wBN 과 cBN은 강한 $sp^3$ 결합특성을 가지고 있다. 현재까지 $sp^3$결합을 갖는 BN의 우수한 특성을 응용하기 위한 수 많은 연구들이 있어왔다. 특히 cBN은 다이아몬드에 버금가는 높은 경도뿐만 아니라 높은 화 학적 안정성 및 열전도성 등 우수한 물리화학적 특성을 가지고 있어 마찰.마모, 전자, 광학 등의 여러 분야에서의 산업적 응용이 크게 기대되고 있다. 그러나 이와 같이 BN박막의 기계적 물성과 관련한 연 구는 많이 진행되어 왔으나 전기.전자적, 광학적 특성에 관한 연구는 미비한 실정이다. 따라서 본 연구에서는 BN박막의 또 다른 웅용 분야를 탐색하고자 ME - ARE (Magnetically Enhanced A Activated Reactive Evaporation)법 에 의 해 합성 된 BN박막의 광학적 특성 에 관하여 조사하였다. BN박 막합성 은 전자총에 의 해 증발된 보론과 질소.아르곤 플라즈마의 활성 화반응증착(Activated Reactive E Evaporation)에 의해 이루어졌다. 기존의 ARE장치와 달리 열음극(hot cathode)과 양극(anode)사이에 평 행자기장을 부가하여 플라즈마의 증대시켜 반웅효율을 높였다. 합성실험용 모재로는 기본적인 특성 분 석을 위해 p-type으로 도핑된 (100) Si웨이퍼를 $30{\times}40mm$크기로 절단 후, 10%로 희석된 완충불산용액 에 10분간 침적하여 표면의 산화층을 제거한 후 사용하였으며, 광학특성 분석을 위해 $30{\times}30mm$의 glass를 아세톤으로 탈지.세척한 후 사용하였다. 박막합성실험에서 BN의 광학적 특성에 미치는 공정변수의 영향을 파악하기 위하여, 기판바이어스 전압, discharge 전류, $Ar/N_2$가스 유량비 등을 달리하여 증착하였다. 증착된 박막은 FTIR 분석을 통하 여 결정성을 확인하였으며, AFM 분석을 통하여 코팅층의 두께를 측정하였고, UV - VIS spectormeter를 이용하여 투광특성을 평가하였다.

• Tunnel and Underground Space
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• v.22 no.1
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• pp.43-53
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• 2012

Stability of cut-slope, the orientation and dimension of which are gradually changed, has been analyzed by employing the cross-section method capable of comprehensibly considering the lithological, structural and mechanical characteristics of slope rock. Lithological fragility is investigated by inspecting the drilled core logs and BIPS image has been taken to delineate the rock structure. Engineering properties of drilled-core including the joint shear strength have been also measured. Potential failure modes of cut-slope and failure-induced joints are identified by performing the stereographic projection analysis. Traces of potential failure-induced joints are drawn on the cross-section which depicts the excavated geometry of cut-slope. Considering the distribution of potential plane failure-induced joint traces blocks of plane failure mode are hypothetically formed. The stabilities and required reinforcements of plane failure blocks located at the different excavation depth have been calculated to confirm the applicability of the cross-section method for the optimum cut-slope design.

• Tunnel and Underground Space
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• v.28 no.4
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• pp.343-357
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• 2018

Algorithm which can analyze the slope failure behavior utilizing the comprehensive information of the dense point of joint poles and the joint set orientations, both of which are obtained statistically, and the defect pattern of pole distribution has been developed. This method overcomes the potential incorrectness of the hemispheric projection method utilizing the joint set orientations only and also enhances the reliability of slope failure analysis. To this end a method capable of calculating the joint dispersion index directly from the joint pole distribution, instead of contour map, has been devised. The representative orientations for the slope failure analysis has been determined by considering the number and orientations of cone angle-dependent joint sets as well as the joint dispersion index. By engaging these representative orientations to the hemispheric projection analysis more reliable slope failure examination has been carried out. Sensitivity analysis for the potentially unstable slope of plane failure mode has been performed. Significance of joint strength index and the external seismic loading on the slope stability has been fully analyzed.