• Title/Summary/Keyword: Methods for deformation control

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Study on the Weld-Induced Deformation Control of Panel Blocks (블록조립시 변형제어에 관한 연구)

  • 이주성
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2000.10a
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    • pp.275-278
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    • 2000
  • This paper is concerned with the simulator to estimate deformation due to welding of panel blocks. An efficient computer program system has been developed which can be applied both to estimation of weld-induced deformation under the given welding conditions and to reflection of effect when methods for deformation control are applied. This paper briefly describes the background of the present simulator and sows some results applying the simulator to estimation of weld-induced deformation. In addition results when methods for deformation control are applied are also included.

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A Study on the Accuracy Control of Panel Blocks (평블록의 용접변형제어에 관한 연구)

  • 이주성
    • Journal of Ocean Engineering and Technology
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    • v.18 no.1
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    • pp.35-40
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    • 2004
  • This paper is concerned with the simulator's ability to estimate deformation due to welding of panel blocks. An efficient computer program system has been developed which can be applied both to estimation of weld-induced deformation, under the given welding conditions, and to reflection of effect when methods for deformation control of are applied. This paper briefly describes the background of the present simulator and shows some results applying the simulator to the estimation of weld-induced deformation. In addition, the results when methods for deformation control are applied are also included.

Settlement behaviours and control measures of twin-tube curved buildings-crossing shield tunnel

  • Jianwei, Jia;Ruiqi, Gao;Defeng, Wang;Jianjun, Li;Ziwen, Song;Jinghui, Tan
    • Structural Engineering and Mechanics
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    • v.84 no.5
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    • pp.699-706
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    • 2022
  • Settlement control techniques are critical for the safety of shield tunnel constructions, especially for facing complex situations. In this study, the shield tunnel structure from Huaita east road station to Heping Road station in Xuzhou metro No.3 line (China) is taken as engineering background, which has various complex problems of the upper-soft and lower-hard composite stratum conditions, twin curve shield tunnels, and underpass the foundation of the piled raft. The deformation characteristics of shield tunnelling passing through buildings are explored. Subsequently, comprehensive research methods of numerical simulation and field measurement are adopted to analyzing the effectiveness of settlement control by using the top grouting technique. The results show that the settlement of the buildings has obvious spatial characteristics, and the hysteresis effect can be obviously observed in soil deformation caused by shield construction. Meanwhile, the two shield constructions can cause repeated disturbances, reducing the soil deformation's hysteresis effect. Moreover, the shield tunnel's differential settlement is too large when a single line passes through, and the shield construction of the outer curve can cause more significant disturbance in the tunnel than the inside curve. Notably, the proposed process control parameters and secondary topgrouting method can effectively control the deformation of the shield tunnel, especially for the long-term deformation.

Real-time Shape Manipulation using Deformable Curve-Skeleton

  • Sohn, Eisung
    • Journal of Korea Multimedia Society
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    • v.22 no.4
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    • pp.491-501
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    • 2019
  • Variational methods, which cast deformation as an energy-minimization problem, are known to provide a good trade-off between practicality and speed. However, the time required to deform a fully detailed shape means that these methods are largely unsuitable for real-time applications. We simplify a 2D shape into a curve skeleton, which can be deformed much more rapidly than the original shape. The curve skeleton also provides a simplified control for the user, utilizing a small number of control handles. Our system deforms the curve skeleton using an energy-minimization method and then applies the resulting deformation to the original shape using linear blend skinning. This approach effectively reduces the size of the variational optimization problem while producing deformations of a similar quality to those obtained from full-scale nonlinear variational methods.

Evaluation of Geogrid-Reinforced Subbase Layer Thickness of Permeable Flexible Pavements based on Permanent Deformation Model (지오그리드로 보강된 투수성 연성포장 보조기층제 영구변형을 고려한 층두께 산정 비교 연구)

  • Kwon, Hyeok Min;Oh, Jeongho;Han, Shin-In
    • International Journal of Highway Engineering
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    • v.17 no.1
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    • pp.69-75
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    • 2015
  • PURPOSES : The objective of this study is to evaluate the effectiveness of a geogrid reinforced subbase of permeable flexible pavement structures with respect to permanent deformation. METHODS : Experimental trials employing a repeated triaxial load test scheme were conducted for both a geogrid reinforced subbase material and a control specimen to obtain the permanent deformation properties based on the VESYS model. Along with this, a finite element-based numerical analysis was conducted to predict pavement performance with respect to the rutting model incorporated into the analysis. RESULTSAND CONCLUSIONS : The results of the experimental study reveal that the geogrid reinforcement seems to be effective in mitigating permanent deformation of the subbase material. The permanent deformation was mostly achieved in the early stages of loading and then rapidly reached equilibrium as the number of load applications increased. The ultimate permanent deformation due to the geogrid reinforcement was about 1.5 times less than that of the control specimen. Numerical analysis showed that the permeable, flexible pavement structure with the geogrid reinforced subbase also exhibits less development of rutting throughout the service life. This reduction in rutting led to a 20% decrease in thickness of the subbase layer, which might be beneficial to reduce construction costs unless the structural adequacy is not ensured. In the near future, further verification must be conducted, both experimentally and numerically, to support these findings.

Efficient Procedural Modeling of Trees Based on Interactive Growth Volume Control

  • Kim, Jinmo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.9
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    • pp.2232-2245
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    • 2013
  • The present study proposes efficient procedural modeling methods for enabling the growth and creation of various trees with minimal user control. Growth volume algorithms are utilized in order to easily and effectively calculate many parameters that determine tree growth, including branch propagation. Procedural methods are designed so that users' interactive control structures can be applied to these algorithms to create unique tree models efficiently. First, through a two-line-based interactive growth volume control method, the growth information that determines the overall shape of the tree is intuitively adjusted. Thereafter, independent branch control methods designed to control individual branches are added to the growth deformation in order to enable the growth of unique trees. Whether the growth processes of desired trees can be easily and intuitively controlled by the proposed method is verified through experiments. Methods that can apply the proposed methods are also verified.

Study on muscle deformation and human body modeling (근육 변형 및 인체 모델링에 관한 연구)

  • 이환용;김명수;박찬모
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10a
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    • pp.752-757
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    • 1991
  • Recently, human body modeling with muscle deformation has become an attractive research area in computer animation. There are many modeling tools available for solids such as mechanical part. However, there are many limitations of these conventional methods in modeling flexible objects with delicate motions and shapes such as human bodies. In this paper we present a new modeling technique for human body with muscle deformation. Each muscle is represented as a generalized cylinder and its shape deformation is computed using simple algorithm. The human body is a union of muscles, bones, organs, etc. The modeling data are obtained from the information on the human anatomy. To demonstrate the feasibility of our method, we model several arm muscles and simulate the skin deformation. As a result we have obtained a realistic shape deformation.

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Three Dimensional Last Data Generation System Design Utilizing SFFD and LFFD (LFFD 및 SFFD를 이용한 3차원 라스트 데이터 생성시스템 개발)

  • Kim, Si-Kyung;Park, In-Duck
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.2
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    • pp.113-118
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    • 2006
  • A new last design approach based on the Limb line FFD (LFFD) and Scale factor FFD (SFFD) is presented in this paper. The proposed last design method utilizes the dynamic trimmed parametric patches for the measured foot 3D data and last 3D data. Furthermore, the proposed last data generation system utilizes cross sectional data extracted obtained from the measured 3D foot data. First, the last design rule of the LFFD is constructed on the FFD lattice based on foot last shape analysis. Secondly, SFFD is constructed on the LFFD new lattice based on scale factor deformation. The scale factor is constructed on the boundary edges of polygonized patch and the cross section last data boundary edge of the polygon object. Suppose the two boundary curves have been preprocessed so that they run in the same direction and they forms the SF(Scale Factor). In addition, the control points of FFD lattice are derived with cross. sectional data interpolation methods from a finite set of 3D foot data.

Introduction of Prediction Method of Welding Deformation by Using Laminated Beam Modeling Theory and Its Application to Railway Rolling Stock

  • Mun, Hyung-Suk;Jang, Chang-Doo
    • International Journal of Railway
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    • v.2 no.4
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    • pp.175-179
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    • 2009
  • The welding deformation and its prediction method at the HAZ (Heat-Affected Zone) are presented in this paper. The inherent strain method is well known as analytical method to predict welding deformation of large scale welded structure. Depend on the size of welding deformation in welding joints, the fatigue life, the stress concentration factor and the manufacturing quality of welded structure are decided. Many welded joints and its manufacturing control techniques are also required to railway rolling stock and its structural parts such as railway carbody and bogie frame. Proposed methods in this paper focus on the two different the inherent strain area at HAZ. This is main idea of proposed method and it makes more reliable result of welding deformation analysis at the HAZ.

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Assessment of Image Registration for Pressure-Sensitive Paint (Pressure Sensitive Paint를 이용한 압력장 측정기술의 이미지 등록에 관한 연구)

  • Chang, Young-Ki;Park, Sang-Hyun;Sung, Hyung-Jin
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.3
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    • pp.271-280
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    • 2004
  • Assessment of image registration for Pressure Sensitive Paint (PSP) was performed. A 16 bit camera and LED lamp were used with Uni-FIB paint (ISSI). Because of model displacement and deformation at 'wind-on' condition, a large error of the intensity ratio was induced between 'wind-on' and' wind-off images. To correct the error, many kinds of image registrations were tested. At first, control points were marked on the model surface to find the coefficients of polynomial transform functions between the 'wind-off' 'wind-on' images. The 2nd-order polynomial function was sufficient for representing the model displacement and deformation. An automatic detection scheme was introduced to find the exact coordinates of the control points. The present automatic detection algorithm showed more accurate and user-friendly than the manual detection algorithm. Since the coordinates of transformed pixel were not integer, five interpolation methods were applied to get the exact pixel intensity after transforming the 'wind-on' image. Among these methods, the cubic convolution interpolation scheme gave the best result.