The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Muneo Hori - One of the best experts on this subject based on the ideXlab platform.
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three dimensional photoelasticity with equilibrium constraint
Applied Physics Letters, 2008Co-Authors: Kenji Oguni, M L L Wijerathne, Muneo HoriAbstract:A method for stress field tomography based on three dimensional photoelasticity has been developed. The proper treatment of the nonlinearity and the ill-posedness is the key to the robust tomographic method. In the proposed method, the nonlinearity has been addressed by the load Incremental Approach which divides the nonlinear solution space into segments with unique solutions. Also, the ill-posedness has been suppressed by introducing constraints from the equilibrium of the stress field. Validating both numerically and experimentally, the proposed method is shown to be robust enough and applicable to experimental stress measurements.
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stress field tomography based on 3d photoelasticity
Journal of The Mechanics and Physics of Solids, 2008Co-Authors: M L L Wijerathne, Kenji Oguni, Muneo HoriAbstract:A tomographic method for identification of stress fields based on 3D photoelasticity has been developed. A second order tensor field tomographic method based on the general inverse problem of 3D photoelasticity, previously developed by the authors, is found to be highly sensitive to errors in photoelastic observations. In this study a new tomographic method for stress field with fairly high robustness to errors in photoelastic observations has been developed by introducing both equilibrium condition and linear elasticity to the previously developed general tensor field tomographic method. This new stress field tomographic method expands unknown 3D stress distributions as a linear combination of independent set of basis functions and a new inverse problem is posed: identify the amplitudes of basis functions based on photoelastic observations. Just as the inverse problem of 3D photoelasticity, this newly posed inverse problem is also nonlinear and ill posed. Unlike conventional Approaches to 3D photoelasticity, both these nonlinearity and ill-posedness are properly treated using a load Incremental Approach. Load Incremental Approach chops the nonlinear solution space into segments with unique solutions by conducting photoelastic observations at sufficiently small increments in external load. Validating both numerically and experimentally, it is shown that this new stress field tomographic method has sufficient robustness against errors in photoelastic observations and is applicable to experimental stress measurements.
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tensor field tomography based on 3d photoelasticity
Mechanics of Materials, 2002Co-Authors: M L L Wijerathne, Kenji Oguni, Muneo HoriAbstract:A new method for non-destructive measurement of arbitrary 3D stress state using photoelasticity has been developed. The new Approach, namely, load Incremental Approach, is an attempt to solve the non-linear inverse problem of 3D photoelasticity by considering change in stress state for a load increment and linearizing the non-linear governing equation. As long as the applied load increment is small and photoelastic images are taken with high resolution in load increment, this method works and can reconstruct arbitrary 3D stress state. Numerical simulations clarify the effect of (i) the material sensitivity, (ii) the number of the observations and (iii) the constraint on the observation directions on the performance of the proposed method. These results provide the fundamental data for designing the experimental setup for 3D photoelasticity.
M L L Wijerathne - One of the best experts on this subject based on the ideXlab platform.
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three dimensional photoelasticity with equilibrium constraint
Applied Physics Letters, 2008Co-Authors: Kenji Oguni, M L L Wijerathne, Muneo HoriAbstract:A method for stress field tomography based on three dimensional photoelasticity has been developed. The proper treatment of the nonlinearity and the ill-posedness is the key to the robust tomographic method. In the proposed method, the nonlinearity has been addressed by the load Incremental Approach which divides the nonlinear solution space into segments with unique solutions. Also, the ill-posedness has been suppressed by introducing constraints from the equilibrium of the stress field. Validating both numerically and experimentally, the proposed method is shown to be robust enough and applicable to experimental stress measurements.
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stress field tomography based on 3d photoelasticity
Journal of The Mechanics and Physics of Solids, 2008Co-Authors: M L L Wijerathne, Kenji Oguni, Muneo HoriAbstract:A tomographic method for identification of stress fields based on 3D photoelasticity has been developed. A second order tensor field tomographic method based on the general inverse problem of 3D photoelasticity, previously developed by the authors, is found to be highly sensitive to errors in photoelastic observations. In this study a new tomographic method for stress field with fairly high robustness to errors in photoelastic observations has been developed by introducing both equilibrium condition and linear elasticity to the previously developed general tensor field tomographic method. This new stress field tomographic method expands unknown 3D stress distributions as a linear combination of independent set of basis functions and a new inverse problem is posed: identify the amplitudes of basis functions based on photoelastic observations. Just as the inverse problem of 3D photoelasticity, this newly posed inverse problem is also nonlinear and ill posed. Unlike conventional Approaches to 3D photoelasticity, both these nonlinearity and ill-posedness are properly treated using a load Incremental Approach. Load Incremental Approach chops the nonlinear solution space into segments with unique solutions by conducting photoelastic observations at sufficiently small increments in external load. Validating both numerically and experimentally, it is shown that this new stress field tomographic method has sufficient robustness against errors in photoelastic observations and is applicable to experimental stress measurements.
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tensor field tomography based on 3d photoelasticity
Mechanics of Materials, 2002Co-Authors: M L L Wijerathne, Kenji Oguni, Muneo HoriAbstract:A new method for non-destructive measurement of arbitrary 3D stress state using photoelasticity has been developed. The new Approach, namely, load Incremental Approach, is an attempt to solve the non-linear inverse problem of 3D photoelasticity by considering change in stress state for a load increment and linearizing the non-linear governing equation. As long as the applied load increment is small and photoelastic images are taken with high resolution in load increment, this method works and can reconstruct arbitrary 3D stress state. Numerical simulations clarify the effect of (i) the material sensitivity, (ii) the number of the observations and (iii) the constraint on the observation directions on the performance of the proposed method. These results provide the fundamental data for designing the experimental setup for 3D photoelasticity.
Kenji Oguni - One of the best experts on this subject based on the ideXlab platform.
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three dimensional photoelasticity with equilibrium constraint
Applied Physics Letters, 2008Co-Authors: Kenji Oguni, M L L Wijerathne, Muneo HoriAbstract:A method for stress field tomography based on three dimensional photoelasticity has been developed. The proper treatment of the nonlinearity and the ill-posedness is the key to the robust tomographic method. In the proposed method, the nonlinearity has been addressed by the load Incremental Approach which divides the nonlinear solution space into segments with unique solutions. Also, the ill-posedness has been suppressed by introducing constraints from the equilibrium of the stress field. Validating both numerically and experimentally, the proposed method is shown to be robust enough and applicable to experimental stress measurements.
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stress field tomography based on 3d photoelasticity
Journal of The Mechanics and Physics of Solids, 2008Co-Authors: M L L Wijerathne, Kenji Oguni, Muneo HoriAbstract:A tomographic method for identification of stress fields based on 3D photoelasticity has been developed. A second order tensor field tomographic method based on the general inverse problem of 3D photoelasticity, previously developed by the authors, is found to be highly sensitive to errors in photoelastic observations. In this study a new tomographic method for stress field with fairly high robustness to errors in photoelastic observations has been developed by introducing both equilibrium condition and linear elasticity to the previously developed general tensor field tomographic method. This new stress field tomographic method expands unknown 3D stress distributions as a linear combination of independent set of basis functions and a new inverse problem is posed: identify the amplitudes of basis functions based on photoelastic observations. Just as the inverse problem of 3D photoelasticity, this newly posed inverse problem is also nonlinear and ill posed. Unlike conventional Approaches to 3D photoelasticity, both these nonlinearity and ill-posedness are properly treated using a load Incremental Approach. Load Incremental Approach chops the nonlinear solution space into segments with unique solutions by conducting photoelastic observations at sufficiently small increments in external load. Validating both numerically and experimentally, it is shown that this new stress field tomographic method has sufficient robustness against errors in photoelastic observations and is applicable to experimental stress measurements.
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tensor field tomography based on 3d photoelasticity
Mechanics of Materials, 2002Co-Authors: M L L Wijerathne, Kenji Oguni, Muneo HoriAbstract:A new method for non-destructive measurement of arbitrary 3D stress state using photoelasticity has been developed. The new Approach, namely, load Incremental Approach, is an attempt to solve the non-linear inverse problem of 3D photoelasticity by considering change in stress state for a load increment and linearizing the non-linear governing equation. As long as the applied load increment is small and photoelastic images are taken with high resolution in load increment, this method works and can reconstruct arbitrary 3D stress state. Numerical simulations clarify the effect of (i) the material sensitivity, (ii) the number of the observations and (iii) the constraint on the observation directions on the performance of the proposed method. These results provide the fundamental data for designing the experimental setup for 3D photoelasticity.
Jianhui Lin - One of the best experts on this subject based on the ideXlab platform.
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a rough set based Incremental Approach for updating approximations under dynamic maintenance environments
IEEE Transactions on Knowledge and Data Engineering, 2013Co-Authors: Hongmei Chen, Da Ruan, Jianhui LinAbstract:Approximations of a concept by a variable precision rough-set model (VPRS) usually vary under a dynamic information system environment. It is thus effective to carry out Incremental updating approximations by utilizing previous data structures. This paper focuses on a new Incremental method for updating approximations of VPRS while objects in the information system dynamically alter. It discusses properties of information granulation and approximations under the dynamic environment while objects in the universe evolve over time. The variation of an attribute's domain is also considered to perform Incremental updating for approximations under VPRS. Finally, an extensive experimental evaluation validates the efficiency of the proposed method for dynamic maintenance of VPRS approximations.
Junbo Zhang - One of the best experts on this subject based on the ideXlab platform.
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a rough set based Incremental Approach for learning knowledge in dynamic incomplete information systems
International Journal of Approximate Reasoning, 2014Co-Authors: Dun Liu, Junbo ZhangAbstract:With the rapid growth of data sets nowadays, the object sets in an information system may evolve in time when new information arrives. In order to deal with the missing data and incomplete information in real decision problems, this paper presents a matrix based Incremental Approach in dynamic incomplete information systems. Three matrices (support matrix, accuracy matrix and coverage matrix) under four different extended relations (tolerance relation, similarity relation, limited tolerance relation and characteristic relation), are introduced to incomplete information systems for inducing knowledge dynamically. An illustration shows the procedure of the proposed method for knowledge updating. Extensive experimental evaluations on nine UCI datasets and a big dataset with millions of records validate the feasibility of our proposed Approach.
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an Incremental Approach for rule induction under coarsening and refining of attribute values in e business systems
International Conference on e-Business, 2010Co-Authors: Dun Liu, Junbo ZhangAbstract:The variation of attribute values is an important case in the dynamic EBusiness systems. With the rapid increase and update of data sets in business database everyday, a new Incremental model, Approach as well as its algorithm is presented for rule induction under coarsening and refining of attribute values. An example with online-shopping illuminate our method and experiments validate the feasibility of the Incremental Approach.
