• Journal of information and communication convergence engineering
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• 제10권4호
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• pp.378-383
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• 2012

This paper presents the implementation of an automatic road sign recognizer for an intelligent transport system. In this system, lists of road signs are processed with actions such as line segmentation, single sign segmentation, and storing an artificial sign in the database. The process of taking the video stream and extracting the road sign and storing in the database is called the road sign recognition. This paper presents a study on recognizing traffic sign patterns using a segmentation technique for the efficiency and the speed of the system. The image is converted from one scale to another scale such as RGB to grayscale or grayscale to binary. The images are pre-processed with several image processing techniques, such as threshold techniques, Gaussian filters, Canny edge detection, and the contour technique.

• 보존과학연구
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• 통권29호
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• pp.45-64
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• 2008

'No-An-Dang' in 'Un-Hyeun palace' was using as a guesthouse by 'dea-won-goon' built in 1864. 'No-An-Dang tablet' exhibited in 'No-An-Dang' seems to be made by using the letters which were written by 'Choo-sa Kim Jeong-Hee'. This tablet was manufactured by special processes; wood frame which was made of a Korean white pine was drawn patterns by variety pigment and latticed inside are joined with 3 of horizontal square wooden sticks and 7 of vertical square wooden sticks, then several sheets of the paper mulberry put on this frame and sheets cut along the edge of letter attached lastly. This structure of tablet could cause more conservation problems than only made in wooden structures. Therefore, replica was made and exhibited in bad condition and original one kept in museum storage for effective conservation of artefacts.

• 제어로봇시스템학회논문지
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• 제10권9호
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• pp.779-784
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• 2004

This paper describes a sonic polygonal multiple reflection range sensor (SPMRS), which uses multiple reflection properties usually ignored in ultrasonic sensors as disturbances or noises. Targets such as a plane, corner, edge, or cylinder in indoor environments can easily be detected by the multiple reflection patterns obtained with a SPMRS system. Target classification and feature data extraction, such as distance and azimuth to the target, are computed simultaneously by considering the geometrical relationships between the detected targets, and finally the environment model is generated by refining the detected targets. In addition, the narrow field of view of a sonar range sensor is increased and the scanning time is reduced by active motion of the SPMRS stepping servomechanism.

• 대한전자공학회논문지
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• 제25권8호
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• pp.874-883
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• 1988

A complete form of physical optics solution to the diffraction of electromagnetic waves by a dielectric wedge with arbitrary dielectric constant and general wedge angle is obtained for an incident plane wave with any angle. Based on the formulation of dual integral equation in the spectral domain, the physical optics solution is constructed by sum of geometrical optics term including multiple reflection inside the wedge and the edge diffracted field, of which diffraction functions are represented in a quite simple form as series of cotangent functions weighted by the Fresnel reflection coefficients. Since diffraction patterns of physical optics are discontinous at dielectric interfaces, Part II and III of these three companion papers will be concerned with correction to the error of the physical optics approximation.

• 대한전자공학회논문지
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• 제26권7호
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• pp.1-7
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• 1989

가장자리로 부터 역비례로 저항률이 변하는 반평면에 H분극 평면파가 입사되는 경우, 산란파를 Kontorovich-Lebedev 변환을 이용해서 정확한 적분식으로 얻었으며, 이로부터 모든 각도에서 쓸 수 있는 균일 근사식 및 계산된 산란파를 광선적(光線的)으로 해석할 수 있도록 해주는 비균일 근사식도 구했다. 저항율의 상수 여러 값에 대하여 가장자리 회절 패턴을 보였다. 결과들은 물리적으로 타당함을 알 수 있었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.458-461
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• 2006

Early age cracking of concrete is a widespread and complicated problem, and diverse applications in practical engineering have focused on this issue. Since massive concrete base slab composes the infrastructure of other concrete structures such as pier, concrete dam, and high rise buildings, early age cracking of that is considered as a crucial problem. In this study, finite element analysis (FEA) implemented with the age-dependent microplane model was performed. For a massive concrete base slab, cracking initiation and propagation, and deformation variation were investigated with concrete age. In massive concrete slab, autogenous shrinkage increases the risk of early age cracking and it reduces reinforcement effect on control of early age cracking. Gradual crack occurrence is experienced from exterior surface towards interior of the slab in case of combined hydration heat and autogenous shrinkage. FEA implemented with enhanced microplane model successfully simulates the typical cracking patterns due to edge restraint in concrete base slab.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2009년도 정보 및 제어 심포지움 논문집
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• pp.222-224
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• 2009

This paper presents an algorithm that extracts road lane's specific information by using HSI color information and performance enhancement of lane detection base on vision processing of drive assist. As a preprocessing for high speed lane detection, the optimal extraction of region of interest for lane boundary(ROI-LB) can be processed to reduction of detection region in which high speed processing is enabled and it also increases reliabilities by deleting edges those are misrecognized. Road lane is extracted with simultaneous processing of noise reduction and edge enhancement using the Laplacian filter, the reliability of feature extraction can be increased for various road lane patterns. Since noise can be removed by using saturation and brightness of HSI color model. Also it searches for the road lane's color information and extracts characteristics. The real road experimental results are presented to evaluate the effectiveness of the proposed method.

• 대한기계학회논문집A
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• 제26권7호
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• pp.1302-1308
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• 2002

Thermo-mechanical and flexural behavior of a wire-bond plastic ball grid array (WB-PBGA) package are characterized by high sensitive moire interferometry. Moire fringe patterns are recorded and analyzed for several bending loads and temperatures. At the temperature higher than $100^{\circ}C$, the inelastic deformation in solder balls become more dominant, so that the bending of the molding compound decreases while temperature increases. The deformation caused by thermally induced bending is compared with that caused by mechanical bending. The strain results show that the solder ball located at the edge of the chip has largest shear strain by the thermal load while the maximum average shear strain by the bending moment occurs in the end solder.

• 대한기계학회논문집
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• 제8권5호
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• pp.401-407
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• 1984

본 연구에서는 구속공구 및 정상공구에 대하여 공구경사면의 전단응력과 수직 응력을 해석하고 칩 유동시의 마찰계수분포를 검토하였다.

• Journal of Mechanical Science and Technology
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• 제17권12호
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• pp.2116-2124
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• 2003

An experimental study providing additional knowledge of quasi-conical symmetry in swept shock wave/turbulent boundary-layer interactions is described. When a turbulent boundary layer on the flat plate is subjected to interact with a swept planar shock wave, the interaction flowfield far from fin leading edge has a nature of conical symmetry, which topological features of the interaction flow appear to emanate from a virtual conical origin. Surface streakline patterns obtained from the kerosene-lampblack tracings have been utilized to obtain representative surface features of the flow, including the location of the virtual conical origin. The scaling law for the sharp-fin interactions suggested by previous investigators has been reexamined for different freestream Mach numbers. It is noticed that the scaling law reasonably agrees with the present experimental data, however, that the law is not appropriate to estimate the location of the virtual conical origin. Further knowledge of the correlation for the virtual conical origin has thus been proposed.