• Title/Summary/Keyword: Alignment Model

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Comparison of the Body Alignment during Standing on Level and Wedge Board (평지와 쐐기 발판(wedge board) 위에 기립 시 신체정렬 비교)

  • Lee, Jeong-Weon
    • Physical Therapy Korea
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    • v.9 no.1
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    • pp.53-61
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    • 2002
  • The purpose of this study was to compare the body alignment during standing on level and wedge board. Twenty healthy college students (8 females, 12 males) were evaluated in this study. Diagnostic contourline potographic imaging system (Model JTC-1, Jodang Trading Co.) was used to measure body alignment. Sagittal and frontal plane images were used to analyze the body alignment. The result showed that the cervical and lumbar lordotic curve significantly decreased during standing on wedge board when compared with standing on level. On the other hand, thoracic kyphosis significantly increased during standing on wedge board. There was no significant difference in body alignment according to gender, weight, and height. Clinically, patients with low back pain and severe lordosis may be affected by heel wedge. Further study is needed to identify whether the standing on wedge board can change the body alignment in patients with low back pain and spinal deformity.

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Mathematical Optimization Models for Determination of Optimal Vertical Alignment (종단선형설계 최적화 기법에 관한 연구)

  • 강성철;전경수;박영부
    • Journal of Korean Society of Transportation
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    • v.12 no.3
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    • pp.5-13
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    • 1994
  • In the fields of rail and road design, most vertical alignment design have been thus far heavily dependent upon trial-and-errors of experienced engineers. However, it has long been inefficient in productivity of designing process. In order to overcome this inefficiency, this paper presents the optimal vertical alignment design method using mathematical optimization techniques. For optimization, mathematical model to minimize the construction cost is formulated and the separable programming technique and the Zoutendijk method are introduced to solve it. As result, it is shown that this optimization technique can give efficient solutions to all vertical alignment design fields with properly-estimated cost function.

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Proposing Shape Alignment for an Improved Active Shape Model (ASM의 성능향상을 위한 형태 정렬 방식 제안)

  • Hahn, Hee-Il
    • Journal of Korea Multimedia Society
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    • v.15 no.1
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    • pp.63-70
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    • 2012
  • In this paper an extension to an original active shape model(ASM) for facial feature extraction is presented. The original ASM suffers from poor shape alignment by aligning the shape model to a new instant of the object in a given image using a simple similarity transformation. It exploits only informations such as scale, rotation and shift in horizontal and vertical directions, which does not cope effectively with the complex pose variation. To solve the problem, new shape alignment with 6 degrees of freedom is derived, which corresponds to an affine transformation. Another extension is to speed up the calculation of the Mahalanobis distance for 2-D profiles by trimming the profile covariance matrices. Extensive experiment is conducted with several images of varying poses to check the performance of the proposed method to segment the human faces.

Automatically Extracting Unknown Translations Using Phrase Alignment (정렬기법을 이용한 미등록 대역어의 자동 추출)

  • Kim, Jae-Hoon;Yang, Sung-Il
    • The KIPS Transactions:PartB
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    • v.14B no.3 s.113
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    • pp.231-240
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    • 2007
  • In this paper, we propose an automatic extraction model for unknown translations and implement an unknown translation extraction system using the proposed model. The proposed model as a phrase-alignment model is incorporated with three models: a phrase-boundary model, a language model, and a translation model. Using the proposed model we implement the system for extracting unknown translations, which consists of three parts: construction of parallel corpora, alignment of Korean and English words, extraction of unknown translations. To evaluate the performance of the proposed system we have established the reference corpus for extracting unknown translation, which comprises of 2,220 parallel sentences including about 1,500 unknown translations. Through several experiments, we have observed that the proposed model is very useful for extracting unknown translations. In the future, researches on objective evaluation and establishment of parallel corpora with good quality should be performed and studies on improving the performance of unknown translation extraction should be kept up.

A Method of Tunnel Information Modeling Reflecting Curved Alignment and Model-based Information Management using IFC Data Schema (곡선 선형을 반영한 터널 정보모델링 및 IFC 데이터 스키마를 활용한 모델기반의 정보관리 방안)

  • Jang, Seong Geun;Kwon, Tae Ho;Park, Sang I.;Lee, Sang-Ho
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.30 no.6
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    • pp.549-557
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    • 2017
  • In order to improve the productivity in the civil engineering field, efforts to apply BIM have been continuing, however, research on information modeling of tunnel structures considering alignment is insufficient. In this study, we proposed the method of building tunnel models reflecting curved alignment by transferring point data to BIM Authoring Tools(BAT) through discretization of alignment in Alignment-centered Modeling Tools(AMT). IFC data schema was derived to consider the physical and spatial elements of tunnel structures and alignment and IFC-based information management for tunnel alignment, tunnel structures and ground conditions was possible by referring to the extended data schema and including meanings in IFC property sets. The ratings for ground condition in Rock Mass Rating(RMR) and Q-system was automatically derived by using generated information model according to the proposed method.

High-degree Cubature Kalman Filtering Approach for GPS Aided In-Flight Alignment of SDINS

  • Shin, Hyun-choel;Yu, Haesung;Park, Heung-won
    • Journal of Positioning, Navigation, and Timing
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    • v.4 no.4
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    • pp.181-186
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    • 2015
  • A High-degree Cubature Kalman Filter (CKF) is proposed to deal with the Strapdown Inertial Navigation System (SDINS) alignment problem. In-flight Alignment (IFA) is an effective method to compensate for attitude errors of the navigation system. While providing precise attitude error compensation, however, the external source aided alignment often creates a nonlinear filtering problem caused by a large misalignment angle. Introduced recently, Cubature Kalman Filter is a suitable technique for various nonlinear problems. In this paper, a higher degree CKF is applied to this accuracy-is-everything SDINS IFA problem. The simulation results show that the proposed technique outperformed a traditional nonlinear filter in terms of precision and alignment time.

Improvement of Alignment Accuracy in Electron Tomography

  • Jou, Hyeong-Tae;Lee, Sujeong;Kim, Han-Joon
    • Applied Microscopy
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    • v.43 no.1
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    • pp.1-8
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    • 2013
  • We developed an improved method for tilt series alignment with fiducial markers in electron tomography. Based on previous works regarding alignment, we adapted the Levenberg-Marquardt method to solve the nonlinear least squares problem by incorporating a new formula for the alignment model. We also suggested a new method to estimate the initial value for inversion with higher accuracy. The proposed approach was applied to geopolymers. A better alignment of the tilt series was achieved than that by IMOD S/W. The initial value estimation provided both stability and a good rate of convergence since the new method uses all marker positions, including those partly covering the tilt images.

A Transfer Alignment Considering Measurement Time-Delay and Ship Body Flexure (측정치 시간지연과 선체의 유연성을 고려한 전달정렬 기법)

  • Lim, You-Chol;Lyou, Joon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.4 no.1
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    • pp.225-233
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    • 2001
  • This paper deals with the transfer alignment problem of SDINS(StrapDown Inertial Navigation System) subjected to roll and pitch motions of the ship. Specifically, to reduce alignment errors induced by measurement time-delay and ship body flexure, an error compensation method is suggested based on delay state augmentation and DCM(Direction Cosine Matrix) partial matching. A linearized error model for the velocity and attitude matching transfer alignment system is first derived by linearizing the nonlinear measurement equation with respect to its time delay and augmenting the delay state into the conventional linear state equations. And then DCM partial matching is properly combined to reduce effects of a ship's Y axis flexure. The simulation results show that the suggested method is effective enough resulting in considerably less azimuth alignment errors.

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Measurement Time-Delay Error Compensation For Transfer Alignment

  • Lim, You-Chol;Song, Ki-Won;Joon Lyou
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.486-486
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    • 2000
  • This paper is concerned with a transfer alignment method for the SDINS(StrapDown Inertial Navigation System) under ship motions. Major error sources of transfer alignment are data transfer time-delay, lever-arm velocity and ship body flexure. Specifically, to reduce alignment errors induced by measurement time-delay effects, the error compensation method through delay state augmentation is suggested. A linearized error model for the velocity and attitude matching transfer alignment system is first derived by linearizing the nonlinear measurement equation with respect to its time delay and augmenting the delay state into the conventional linear state equations. And then it is shown via observability analysis and computer simulations that the delay state can be estimated and compensated during ship motions resulting in considerably less alignment errors.

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Ship Flexure Error Compensation of Transfer Alignment via Robust State Estimation (강인한 상태추정에 의한 전달정렬의 선체유연성오차 보상)

  • Lim, You-Chol;Lyou, Joon
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.2
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    • pp.178-184
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    • 2002
  • This paper deals with the transfer alignment problem of SDINS(StrapDown Inertial Navigation System) subjected to roll and pitch motions of the ship. In order to reduce alignment errors induced by ship body flexure, a linearized error model for the velocity and attitude matching transfer alignment system is first derived by linearizing the nonlinear measurement equation with respect to the dominant y axis component and defining the flexure state of random constant type. And then a robust state estimation scheme is introduced to account for modeling uncertainty of the flexure. By interpreting the simulation results and comparing with the velocity and DCM(Direction Cosine Matrix) partial matching method, it is shown that the proposed method is effective enough to improve the azimuth alignment performance.