The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Jianjun Shi - One of the best experts on this subject based on the ideXlab platform.
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state space modeling of sheet metal assembly for Dimensional Control
Journal of Manufacturing Science and Engineering-transactions of The Asme, 1999Co-Authors: Jionghua Jin, Jianjun ShiAbstract:In this paper, a state space modeling approach is developed for the Dimensional Control of sheet metal assembly processes. In this study, a 3-2-1 scheme is assumed for the sheet metal assembly. Several key concepts, such as tooling locating error, part accumulative error, and re-orientation error, are defined. The inherent relationships among these error components are developed. Those relationships finally lead to a state space model which describes the variation propagation throughout the assembly process. An observation equation is also developed to represent the relationship between the observation vector (the in-line OCMM measurement information) and the state vector (the part accumulative error). Potential usage of the developed model is discussed in the paper.
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Automotive Body Assembly Modeling for Dimensional Control Using State Spaee Models
IFAC Proceedings Volumes, 1997Co-Authors: Jianjun Shi, Jionghua JinAbstract:Abstract In this paper, a state space modeling approach is developed for the Dimensional Control of autobody assembly processes. In this study, a 3-2-1 scheme is assumed for the sheet metal assembly. Several key concepts, such as tooling locating error, part accumulative error, re-orientation error, are defined. The inherent relationships among these error components are developed. Those relationships finally lead to a state space model which describes the variation propagation throughout the assembly processes. An observation equation is also developed to represent the relationship between observation vector (the in-line OCMM measurement information) and the state vector (the part accumulative error). Potential usage of the developed model is discussed in the paper.
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Flexible beam-based modeling of sheet metal assembly for Dimensional Control
1997Co-Authors: B. W. Shiu, Darek Ceglarek, Jianjun ShiAbstract:In this paper, a flexible beam-based modeling method is proposed for Dimensional Control of the sheet metal assembly process. This method uses developed decomposition principles of key design and manufacturing characteristics for integration of assembly process and product design. It allows for modeling of assembly processes and product in the early design stage of process and product design. The method indudes principles of decoupling automotive parts into beam members, beam connectivity selection, beam-to-beam joint geometry modeling, and process locating points identification. The procedure of incorporating these principles into modeling methodology for a Dimensional Control approach is presented. The presented modeling method was implemented to diagnose multiple dinlensional faults of flexible sheet metal assembly.
Jionghua Jin - One of the best experts on this subject based on the ideXlab platform.
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state space modeling of sheet metal assembly for Dimensional Control
Journal of Manufacturing Science and Engineering-transactions of The Asme, 1999Co-Authors: Jionghua Jin, Jianjun ShiAbstract:In this paper, a state space modeling approach is developed for the Dimensional Control of sheet metal assembly processes. In this study, a 3-2-1 scheme is assumed for the sheet metal assembly. Several key concepts, such as tooling locating error, part accumulative error, and re-orientation error, are defined. The inherent relationships among these error components are developed. Those relationships finally lead to a state space model which describes the variation propagation throughout the assembly process. An observation equation is also developed to represent the relationship between the observation vector (the in-line OCMM measurement information) and the state vector (the part accumulative error). Potential usage of the developed model is discussed in the paper.
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Automotive Body Assembly Modeling for Dimensional Control Using State Spaee Models
IFAC Proceedings Volumes, 1997Co-Authors: Jianjun Shi, Jionghua JinAbstract:Abstract In this paper, a state space modeling approach is developed for the Dimensional Control of autobody assembly processes. In this study, a 3-2-1 scheme is assumed for the sheet metal assembly. Several key concepts, such as tooling locating error, part accumulative error, re-orientation error, are defined. The inherent relationships among these error components are developed. Those relationships finally lead to a state space model which describes the variation propagation throughout the assembly processes. An observation equation is also developed to represent the relationship between observation vector (the in-line OCMM measurement information) and the state vector (the part accumulative error). Potential usage of the developed model is discussed in the paper.
Graham G. Arthur - One of the best experts on this subject based on the ideXlab platform.
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Dimensional Control of sub-half-micron polysilicon gate structures at DUV exposure
Microelectronic Engineering, 1996Co-Authors: Brian Martin, Graham G. ArthurAbstract:Abstract Results of Dimensional Control of sub-half-micron polysilicon gates which pass over LOCOS egdes are presented. Calculations, at duv exposure, using a chemically amplified resist, with and without top and bottom anti-reflective coatings, are performed using SOLID. Results are presented in terms of “swing curves” so that a range of dimensions may be predicted for any linewidth.
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Effect of resist processes on Dimensional Control of submicron polysilicon gate structures
Integrated Circuit Metrology Inspection and Process Control VIII, 1994Co-Authors: Brian Martin, Graham G. ArthurAbstract:Conventional resist, without and with an underlying anti-reflective coating, and a dyed resist are used to calibrate the sub-micron Dimensional Control across a 6 inch diameter wafer coated with LPCVD polysilicon, as used in the manufacture of advanced CMOS devices by i-line technology. Results are referenced to the Dimensional Control measured for the same resist process on bare silicon test wafers. The effect of variable substrate reflectivity, with respect to the different resist processes, is thus assessed. Intra-field Dimensional Control over typical circuit topography is also measured for the same resist processes. Results are related to the amplitude of the linewidth vs resist thickness functions of the appropriate process that are derived from simulations using the SOLID modeling package.
Richard B Kaner - One of the best experts on this subject based on the ideXlab platform.
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morphological and Dimensional Control via hierarchical assembly of doped oligoaniline single crystals
Journal of the American Chemical Society, 2012Co-Authors: Yue Wang, Henry D Tran, Matthew Mecklenburg, Xin N Guan, Adam Z Stieg, B C Regan, David C Martin, Richard B KanerAbstract:Single crystals of doped aniline oligomers are produced via a simple solution-based self-assembly method. Detailed mechanistic studies reveal that crystals of different morphologies and dimensions can be produced by a “bottom-up” hierarchical assembly where structures such as one-Dimensional (1-D) nanofibers can be aggregated into higher order architectures. A large variety of crystalline nanostructures including 1-D nanofibers and nanowires, 2-D nanoribbons and nanosheets, 3-D nanoplates, stacked sheets, nanoflowers, porous networks, hollow spheres, and twisted coils can be obtained by Controlling the nucleation of the crystals and the non-covalent interactions between the doped oligomers. These nanoscale crystals exhibit enhanced conductivity compared to their bulk counterparts as well as interesting structure–property relationships such as shape-dependent crystallinity. Furthermore, the morphology and dimension of these structures can be largely rationalized and predicted by monitoring molecule–solvent...
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nanoscale morphology Dimensional Control and electrical properties of oligoanilines
Journal of the American Chemical Society, 2010Co-Authors: Yue Wang, Henry D Tran, Lei Liao, Xiangfeng Duan, Richard B KanerAbstract:While nanostructures of organic conductors have generated great interest in recent years, their nanoscale size and shape Control remains a significant challenge. Here, we report a general method for producing a variety of oligoaniline nanostructures with well-defined morphologies and Dimensionalities. 1-D nanowires, 2-D nanoribbons, and 3-D rectangular nanoplates and nanoflowers of tetraaniline are produced by a solvent exchange process in which the dopant acid can be used to tune the oligomer morphology. The process appears to be a general route for producing nanostructures for a variety of other aniline oligomers such as the phenyl-capped tetramer. X-ray diffraction of the tetraniline nanostructures reveals that they possess different packing arrangements, which results in different nanoscale morphologies with different electrical properties for the structures. The conductivity of a single tetraaniline nanostructure is up to 2 orders of magnitude higher than the highest previously reported value and rivals that of pressed pellets of conventional polyaniline doped with acid. Furthermore, these oligomer nanostructures can be easily processed by a number of methods in order to create thin films composed of aligned nanostructures over a macroscopic area.
Olivier Laligant - One of the best experts on this subject based on the ideXlab platform.
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Subpixel edge detection for Dimensional Control by artificial vision
Journal of Electronic Imaging, 2001Co-Authors: Frederic Truchetet, Frederic Nicolier, Olivier LaligantAbstract:Dimensional Control by artificial vision is becoming a standard tool for industrialists interested in such remote and without contact measurement methods. The expected accuracy of those systems is dependent on camera resolution. High precision requires very costly charge coupling device sensors and frame grabbers. The proposed method tends to increase significantly the precision of Dimensional measurements without increasing the hardware complexity. This algorithm is also quite robust against noisy images as it can be encountered in real world imaging; a precision of 1/16 pixel can easily be obtained with signal to noise ratio=2 dB. Our approach aims at improving the edge detection process involved in Dimensional Control by artificial vision. A lot of edge detection techniques with pixel resolution are well known and some of them are designed in order to be robust against image corruption. On the other hand B-spline interpolation methods have been considerably improved and popularized by the signal processing techniques proposed by M. Unser et al. An algorithm resulting from the merging of these two ideas is proposed in this paper. In this algorithm, the interpolation is prepared by an optimized filtering and by a detection of local maxima of gradient.
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Subpixel edge detection for Dimensional Control by artificial vision
Machine Vision Applications in Industrial Inspection VIII, 2000Co-Authors: Frederic Truchetet, Olivier LaligantAbstract:Dimensional Control by artificial vision is becoming a standard tool for industrialists interested in such remote and without contact measurement methods. The expected precision of those systems is largely dependent on camera resolution and high precision requires very costly CCD sensor and frame grabber. A method is proposed which tends to increase significantly the precision of Dimensional measurements without increasing the hardware complexity. This algorithm is also quite robust against noisy images such that it could be encountered in real world imaging, a precision of 1/16 pixel can easily be obtained with SNR equals 2 dB. Dimensional Control by artificial vision generally involves an edge detection stage in its process, it is this step that we propose to improve. A lot of edge detection techniques with pixel resolution are well known and some of them are designed in order to be robust against image corruption. On the other hand B-spline interpolation methods have been considerably improved and popularized by the signal processing techniques proposed by M. Unser and Al. An algorithm resulting from the merging of these two ideas is proposed in this paper. In this algorithm, the interpolation is prepared by an optimized filtering and by a detection of local maxima of gradient.
