• Title/Summary/Keyword: fine alignment

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Development of a Fast Alignment Method of Micro-Optic Parts Using Multi Dimension Vision and Optical Feedback

  • Han, Seung-Hyun;Kim, Jin-Oh;Park, Joong-Wan;Kim, Jong-Han
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.273-277
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    • 2003
  • A general process of electronic assembly is composed of a series of geometric alignments and bonding/screwing processes. After assembly, the function is tested in a following process of inspection. However, assembly of micro-optic devices requires both processes to be performed in equipment. Coarse geometric alignment is made by using vision and optical function is improved by the following fine motion based on feedback of tunable laser interferometer. The general system is composed of a precision robot system for 3D assembly, a 3D vision guided system for geometric alignment and an optical feedback system with a tunable laser. In this study, we propose a new fast alignment algorithm of micro-optic devices for both of visual and optical alignments. The main goal is to find a fastest alignment process and algorithms with state-of-the-art technology. We propose a new approach with an optimal sequence of processes, a visual alignment algorithm and a search algorithm for an optimal optical alignment. A system is designed to show the effectiveness and efficiency of the proposed method.

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Pose and Expression Invariant Alignment based Multi-View 3D Face Recognition

  • Ratyal, Naeem;Taj, Imtiaz;Bajwa, Usama;Sajid, Muhammad
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.10
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    • pp.4903-4929
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    • 2018
  • In this study, a fully automatic pose and expression invariant 3D face alignment algorithm is proposed to handle frontal and profile face images which is based on a two pass course to fine alignment strategy. The first pass of the algorithm coarsely aligns the face images to an intrinsic coordinate system (ICS) through a single 3D rotation and the second pass aligns them at fine level using a minimum nose tip-scanner distance (MNSD) approach. For facial recognition, multi-view faces are synthesized to exploit real 3D information and test the efficacy of the proposed system. Due to optimal separating hyper plane (OSH), Support Vector Machine (SVM) is employed in multi-view face verification (FV) task. In addition, a multi stage unified classifier based face identification (FI) algorithm is employed which combines results from seven base classifiers, two parallel face recognition algorithms and an exponential rank combiner, all in a hierarchical manner. The performance figures of the proposed methodology are corroborated by extensive experiments performed on four benchmark datasets: GavabDB, Bosphorus, UMB-DB and FRGC v2.0. Results show mark improvement in alignment accuracy and recognition rates. Moreover, a computational complexity analysis has been carried out for the proposed algorithm which reveals its superiority in terms of computational efficiency as well.

Development of Precision Inspection Technique for Aircraft Parts Having Very Thin Features on CAD/CAI Integration (CAD/CAI 통합에 기초한 박형 단면을 가지는 항공기 터빈블레이드의 정밀측정기술 개발)

  • Park, Hui-Jae;An, U-Jeong;Kim, Wang-Do
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.6
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    • pp.1743-1752
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    • 1996
  • In this paper, a precision inspection technique using CAD/CAI integration is proposed for the parts having very thin and sharp 3 dimensional curve features. The technique begings with feature reconstruction of turbine blades which have 3 dimensional combined feometry, such as splines, and thin circles. The alifnment procedures consistsb of two phases-rough and fine phases : rough phase alignment is based on the conventional 6 point5s probing on the clear cut surfacef, and fine phase alignment is based on the intial measurement on the 3 dimensional curved parts using an lterative measurement feed-back least sequares technique for alignment. Forf the analysis of profile tolerance of parts, the actual measured points are obtained by finding the closet points on the CAD geometry by the developed subdivision technique and the Tschebycheff norm is applied based on iterative fashion, giving accurate profile tolerance value. The developed inspection technique is applied to practical procedures of blade manufacturing and demonstrated high performance.

Hue-assisted automatic registration of color point clouds

  • Men, Hao;Pochiraju, Kishore
    • Journal of Computational Design and Engineering
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    • v.1 no.4
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    • pp.223-232
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    • 2014
  • This paper describes a variant of the extended Gaussian image based registration algorithm for point clouds with surface color information. The method correlates the distributions of surface normals for rotational alignment and grid occupancy for translational alignment with hue filters applied during the construction of surface normal histograms and occupancy grids. In this method, the size of the point cloud is reduced with a hue-based down sampling that is independent of the point sample density or local geometry. Experimental results show that use of the hue filters increases the registration speed and improves the registration accuracy. Coarse rigid transformations determined in this step enable fine alignment with dense, unfiltered point clouds or using Iterative Common Point (ICP) alignment techniques.

SMOLED equipment for Mass-production

  • Kim, Chang-Woo;Cho, Woo-Seok;Kim, Dong-Soo;Bae, Kyung-Bin
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.133-136
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    • 2002
  • It is very important to get a stable and large-capacity organic effusion source for achievement of OLED mass-production equipment. We present an organic effusion source with film uniformity less than ${\pm}$ 5%, the material charge volume, 300cc for $400{\times}400\;mm^2$ substrate. The fine metal shadow mask alignment technology, one of the color forming technique, also have to support more accurate and fast operating in mass-production. In this paper, we will describe the OLED mass-production equipment with the large volume effusion source and the precision shadow mask alignment technique.

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Preparation and Characterization of Ultra-fine PAI Continuous Fibers Using Electrospinning Process (전기방사 공정을 이용한 극세 PAI 연속사 제조 방법에 관한 연구)

  • Lee, Jae-Rock;Ji, Seung-Yong;Hong, Young-Taik;Park, Soo-Jin
    • Applied Chemistry for Engineering
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    • v.17 no.3
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    • pp.331-334
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    • 2006
  • In this study, the ultra-fine fibers (UFs) having an alignment were prepared by electrospinning process, using different collectors made from various materials and collecting methods. A spinning solution was prepared by dissolving poly(amide-co-imide) (PAI) in NMP. The UFs were prepared by using various collectors and collecting methods, and the fibrous shapes were observed by SEM. As a result, a sort of materials of collectors and the collecting methods had not influenced on the average diameters of fibers but the forms of them. The just accumulated UFs on the collectors formed net structures, which had no alignment. On the contrary, the continuously collected UFs formed long fibers with alignment. It was found that the water collector played the roles of the fiber haul, temporary collector, moving path of fibers, and caused some friction between fibers and water, attributed to the formation of continuous UFs at a suitable collecting speed.

Comparing the performance of Supervised Fine-tuning, Reinforcement Learning, and Chain-of-Hindsight with Llama and OPT models (Llama, OPT 모델을 활용한 Supervised Fine Tuning, Reinforcement Learning, Chain-of-Hindsight 성능 비교)

  • Hyeon Min Lee;Seung Hoon Na;Joon Ho Lim;Tae Hyeong Kim;Hwi Jung Ryu;Du Seong Chang
    • Annual Conference on Human and Language Technology
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    • 2023.10a
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    • pp.217-221
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    • 2023
  • 최근 몇 년 동안, Large Language Model(LLM)의 발전은 인공 지능 연구 분야에서 주요 도약을 이끌어 왔다. 이러한 모델들은 복잡한 자연어처리 작업에서 뛰어난 성능을 보이고 있다. 특히 Human Alignment를 위해 Supervised Fine Tuning, Reinforcement Learning, Chain-of-Hindsight 등을 적용한 언어모델이 관심 받고 있다. 본 논문에서는 위에 언급한 3가지 지시학습 방법인 Supervised Fine Tuning, Reinforcement Learning, Chain-of-Hindsight 를 Llama, OPT 모델에 적용하여 성능을 측정 및 비교한다.

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A Multistage In-flight Alignment with No Initial Attitude References for Strapdown Inertial Navigation Systems

  • Hong, WoonSeon;Park, Chan Gook
    • International Journal of Aeronautical and Space Sciences
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    • v.18 no.3
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    • pp.565-573
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    • 2017
  • This paper presents a multistage in-flight alignment (MIFA) method for a strapdown inertial navigation system (SDINS) suitable for moving vehicles with no initial attitude references. A SDINS mounted on a moving vehicle frequently loses attitude information for many reasons, and it makes solving navigation equations impossible because the true motion is coupled with an undefined vehicle attitude. To determine the attitude in such a situation, MIFA consists of three stages: a coarse horizontal attitude, coarse heading, and fine attitude with adaptive Kalman navigation filter (AKNF) in order. In the coarse horizontal alignment, the pitch and roll are coarsely estimated from the second order damping loop with an input of acceleration differences between the SDINS and GPS. To enhance estimation accuracy, the acceleration is smoothed by a scalar filter to reflect the true dynamics of a vehicle, and the effects of the scalar filter gains are analyzed. Then the coarse heading is determined from the GPS tracking angle and yaw increment of the SDINS. The attitude from these two stages is fed back to the initial values of the AKNF. To reduce the estimated bias errors of inertial sensors, special emphasis is given to the timing synchronization effects for the measurement of AKNF. With various real flight tests using an UH60 helicopter, it is proved that MIFA provides a dramatic position error improvement compared to the conventional gyro compass alignment.

Monophthong Analysis on a Large-scale Speech Corpus of Read-Style Korean (한국어 대용량발화말뭉치의 단모음분석)

  • Yoon, Tae-Jin;Kang, Yoonjung
    • Phonetics and Speech Sciences
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    • v.6 no.3
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    • pp.139-145
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    • 2014
  • The paper describes methods of conducting vowel analysis from a large-scale corpus with the aids of forced alignment and optimal formant ceiling methods. 'Read Style Corpus of Standard Korean' is used for building the forced alignment system and a subset of the corpus for the processing and extraction of features for vowel analysis based on optimal formant ceiling. The results of the vowel analysis are reliable and comparable to the results obtained using traditional analytical methods. The findings indicate that the methods adopted for the analysis can be extended and be used for more fine-grained analysis without time-consuming manual labeling without losing accuracy and reliability.