• Title/Summary/Keyword: surface-step

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Curvature and Histogram of oriented Gradients based 3D Face Recognition using Linear Discriminant Analysis

  • Lee, Yeunghak
    • Journal of Multimedia Information System
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    • v.2 no.1
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    • pp.171-178
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    • 2015
  • This article describes 3 dimensional (3D) face recognition system using histogram of oriented gradients (HOG) based on face curvature. The surface curvatures in the face contain the most important personal feature information. In this paper, 3D face images are recognized by the face components: cheek, eyes, mouth, and nose. For the proposed approach, the first step uses the face curvatures which present the facial features for 3D face images, after normalization using the singular value decomposition (SVD). Fisherface method is then applied to each component curvature face. The reason for adapting the Fisherface method maintains the surface attribute for the face curvature, even though it can generate reduced image dimension. And histogram of oriented gradients (HOG) descriptor is one of the state-of-art methods which have been shown to significantly outperform the existing feature set for several objects detection and recognition. In the last step, the linear discriminant analysis is explained for each component. The experimental results showed that the proposed approach leads to higher detection accuracy rate than other methods.

Formation of Fine Pitch Solder Bump with High Uniformity by the Tilted Electrode Ring (경사진 전극링을 이용한 고균일도의 미세 솔더범프 형성)

  • Ju, Chul-Won;Lee, Kyung-Ho;Min, Byoung-Gue;Kim, Seong-Il;Lee, Jong-Min;Kang, Young-il
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.9
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    • pp.798-802
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    • 2005
  • The plating shape in the opening of photoresist becomes gradated shape in the fountain plating system, because bubbles from the wafer surface are difficult to escape from the deep openings, vias. In this paper, the bubble flow from the wafer surface during plating process was studied and we designed the tilted electrode ring to get uniform bump height on all over the wafer and evaluated the film uniformity by SEM and $\alpha-step$. In a-step measurement, film uniformities in the fountain plating system and the tilted electrode ring contact system were $\pm16.6\%,\;\pm4\%$ respectively.

Design of Lateral Controller for Automatic Valet Parking and Its Performance Analysis with Respect to Vehicle Types (자동 발렛 파킹을 위한 횡방향 제어기 설계 및 차종변화에 대한 제어 성능 분석)

  • Choi, Heejae;Song, Bongsob
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.11
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    • pp.1051-1058
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    • 2012
  • The unified lateral control algorithm for automatic valet parking for various types of vehicles is presented and its feasibility is shown experimentally via field tests for the given parking scenario. First, a trajectory generation algorithm for forward driving and backward multi-step parking maneuvers is developed. Then, with consideration of different types of vehicles and operating conditions, a kinematic vehicle model is used and validated using field test data. Using the nonlinear vehicle model, the lateral controller is designed based on dynamic surface control. Finally the proposed lateral control law is validated via hardware-in-the-loop simulations for different types of vehicles and experimentally using a test vehicle through field tests.

Real time observation of reconstruction transition on GaAs (111)B vicinal surface by scanning electron microscopy

  • Ren, Hong-Wen;Tatau Nishinaga
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06a
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    • pp.19-37
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    • 1996
  • Scanning electron microscopy (SEM) has been applied to observe directly the {{{{ SQRT { 19} }}}}${\times}${{{{ SQRT { 19} }}}} and (1${\times}$1)HT reconstructions and the transition associated step bunching on the GaAs (111)B surfaces under As pressure. Close to the transition point, {{{{ SQRT { 19} }}}}${\times}${{{{ SQRT { 19} }}}}an d (1${\times}$1)HT reconstructions are observed in dark and bright domains by SEM and determined by micro-probe reflection high-energy electron diffraction (${\mu}$-RHEED). The reconstruction diagram shows hyster-esis. The stepped surface morphology during the reconstruction transition was unstable. Heavy step bunching with rough macrostep edges was observed.

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Pore Distribution of Porous Silicon layer by Anodization Process

  • Lee, Ki-Yong;Chung, Won-Yong;Kim, Do-Hyun
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06a
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    • pp.494-496
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    • 1996
  • The purpose of this study is to investigate the effect of process conditions on pore distribution in porous silicon layer prepared by electrochemical reaction. Porous silicon layers formed on p-type silicon wafer show the network structure of fine porse whose diameters are less than 100${\AA}$. In n-type porous silicon, selective growth was found on the pore surface by wet etching process after PR patterning. And numerical method showed high current density on the pore tip. With this result we confirmed that pore formation has two steps. First step is the initial attack on the surface and second step is the directional growth on the pore tip.

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Fundamental Study for Optimization of Grinding Condition Using STD11 Material (금형강(STD11)의 연삭가공조건 최적화를 위한 기초 연구)

  • 이영석;하만경;곽재섭;류인일
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.903-906
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    • 1997
  • For the net shape manufacturing, grinding is a important process that influences directly the accuracy and the integrity of products. We studied and researched the grinding force, surface roughness, and grinding wheel durability, according to the change of a feed speed of the table and a depth of the cut step by step with experiment that it is used to WA wheel. Workpiece materials were used STDII. The purpose of this study proposes the basic data for design of the machine tool and for controlling the machining parameters to obtain optimum performance of plunge grinding system during operation.

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The Heat Treatment Characterization of Plasma Sprayed Alumina Coatings (플라즈마 용사법에 의한 $Al_2$O$_3$ 피복층의 열처리효과에 관한 연구)

  • 오익현;김한산;김수식
    • Journal of the Korean institute of surface engineering
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    • v.27 no.3
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    • pp.134-142
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    • 1994
  • $Al_2O_3$coatings on mild steel substrate by plasma spray process were produced to evaluate microstructural characterization and mechanical properties. As-coated $Al_2O_3$coating samplessd were subjected to two heat treat-ment conditions : ⅰ) annealing under vacuum circumstance, ⅱ) hot press treated condition. The two heat treat-ed coatings were investigated in terms of microhardness, adhesion strength, wear resistance, porosity forma-tion, and microstructures. In the case of the coatings which were subject to preparation step ⅰ, the porosity in the coating was decreased with the increase of temperature ($700^{\circ}C$-$1100^{\circ}C$), and the wear resistance, microhardnesss and adhesion strength were increased with the increase of temperature. On the other hand, in the case of the coatings which were subject to preparation step ⅱ, wear resistance and adhesion strength were improved with the increase of temperature and pressure. Experimental measurements of coatings which were produced by both preparation conditions were enhanced compare to those of as-coated coatings.

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Datuming by Wavefield Depth Extrapolation (파동장 외삽을 이용한 데이터밍)

  • Ji Jun
    • Geophysics and Geophysical Exploration
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    • v.1 no.2
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    • pp.116-126
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    • 1998
  • I present a datuming scheme for poststack data that uses wavefield depth extrapolation. The method I have developed allows the use of any depth extrapolation technique, such as phase-shift, split-step, and finite-difference extrapolation. I derive the datuming algorithms by transposing and taking the complex conjugate (i.e. taking adjoint) of the corresponding forward modeling operator, which does upward extrapolation from a flat surface to an irregular surface. The exact adjoint relation between the forward modeling operator and the datuming operator is demonstrated algebraically. Testing the poststack datuming algorithms with synthetic data, using several depth extrapolation algorithms, has shown that the method works well.

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An Analysis of Characteristics of PECVD and LPCVD a-Si Films Crystallized by Excimer Laser (엑시머 레이저를 이용하여 결정화한 PECVD 및 LPCVD 비정질 실리콘 박막의 특성 분석)

  • Jang, K.H.;Lee, S.K.;Jun, M.C.;Han, M.K.
    • Proceedings of the KIEE Conference
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    • 1994.07b
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    • pp.1239-1242
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    • 1994
  • We have characterized XeCl excimer-laser-induced crystallization of thin amorphous silicon films deposited by PECVD (${\alpha}-Si:H$) and LPCVD(${\alpha}-Si$). The electrical and optical properties and surface roughness of crystallized thin films have been measured. The dc conductivities, crystallinity and surface roughness of the films increased as the laser energy density and shot density were increased. Also, we have investigated the effects of 2-step annealing employing SPC and ELA. The properties of 2-step annealed films were better than those of films annealed by ELA only.

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Microstructure and Hot Corrosion Resistance of Aluminide and Chromium-Aluminide Coatings for Inconel 600 (Inconel 600에 있어서 Al 및 Al-Cr擴酸浸透 被覆處理에 따른 被覆層의 特性과 耐蝕性)

  • Chung In-Sang;Park, Kyeung-Chae;Park, Soo-Ho
    • Journal of the Korean institute of surface engineering
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    • v.20 no.3
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    • pp.95-105
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    • 1987
  • For the purpose of improving the hot corrosion resistance of Ni-base superalloy, Inconel 600, aluminide and chromium-aluminide coatings by pack cementation process were studied. The morphology of these coatings is dependent on the type of process employed. And their overall composition depends on the composition of the base alloy and on the nature of the cement. Therefore the different aluminide and chromium-aluminide coatings obtained on a superalloy do not possess the same resistance to oxidation and hot corrosion. The mechanisms governing the formation of the coatings and the composition of the coating were varied by pack composition and temperature, and cyclic hot corrosion resistance of the auluminide coating formed by one-step process was inferior to that of the coating formed by two-step process. and Cr-Al composite coating showed good resistance for cyclic hot corrosion.

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