The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Nobuaki Kawahara - One of the best experts on this subject based on the ideXlab platform.
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Quick-Response Dynamic focusing lens using multilayered piezoelectric bimorph actuator
Micro-Opto-Electro-Mechanical Systems, 2000Co-Authors: Takashi Kaneko, N. Mitsumoto, Kohtaro Ohba, Nobuaki KawaharaAbstract:We present a new micro optical devices, Dynamic focusing lens (DFL) using a multi-layered piezoelectric bimorph micro actuator. DFL is structured to directly deform the lens shape as a crystalline lens of the human eye. The deformable lens is comprised of two thin glass diaphragms with a transparent working fluid sealed between them. The curvature of the lens shape is changed according to the applied voltage of the actuator. DFL shows quick Response up to 150 Hz for focal plane shift because the mass movement can be minimized compared with the conventional focusing method of moving a lens position. We also propose digital all-in-focus microscope system as an application of DFL. This system realizes real-time observation for micro parts assembling with a deep depth of field, as well as three-dimensional shape measurement using only one image sensor. In this paper, a newly developed real-time algorithm called one pixel method for generating clear image having a deep depth of field is described. This method is able to process one original picture (640 x 480 pixels per frame) in approximately 1.0ms. Results of three-dimensional shape measurement in high accuracy using the contrast of brightness method are also discussed.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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A compact and quick-Response Dynamic focusing lens
Sensors and Actuators A: Physical, 1998Co-Authors: Takashi Kaneko, Takuhiro Ohmi, Nobuyuki Ohya, Nobuaki KawaharaAbstract:Abstract A Dynamic focusing lens with a completely new mechanism that can be miniaturized and allows for a quick-Response has been developed. This lens is structured to directly transform the lens shape as a crystalline lens of the human eye. The lens is comprised of two thin glass diaphragms as a refracting surface, with a transparent working fluid sealed between them, and a new type of piezoelectric bimorph actuator. The displacement of the actuator is enlarged by the bimorph structure. The generated force is determined by the layer number of the bimorph cells. When the actuator is driven to push or pull the glass diaphragm at the actuator side, the other glass diaphragm is transformed into a lens shape (convex lens or concave lens) having various curvatures. The focal length of the lens is controlled by the applied voltage to the actuator. The Dynamic focusing lens shows quick Response up to 150 Hz. When the lens is operated over 60 Hz, human visual perception cannot recognize the change of the focal length, and we can observe many images having different focal lengths simultaneously.
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A new smart vision system using a quick-Response Dynamic focusing lens
Proceedings IEEE Thirteenth Annual International Conference on Micro Electro Mechanical Systems (Cat. No.00CH36308), 1Co-Authors: Takashi Kaneko, N. Mitsumoto, Nobuaki KawaharaAbstract:We propose a new smart vision system using a quick-Response Dynamic focusing lens suitable for micro parts assembling. This system realizes real-time observation for micro parts with a deep depth of field, as well as three-dimensional shape measurement using only one image sensor. In this paper, we report a newly developed real-time algorithm called the one pixel method for generating a clear image having a deep depth of field. This method is able to process one original picture (640/spl times/480 pixels per frame) in approximately 1.0 ms. We also report the results of three-dimensional shape measurement with high accuracy using the contrast of brightness method.
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A new, compact and quick-Response Dynamic focusing lens
Proceedings of International Solid State Sensors and Actuators Conference (Transducers '97), 1Co-Authors: Takashi Kaneko, Takuhiro Ohmi, Nobuyuki Ohya, Nobuaki Kawahara, T. HattoriAbstract:A Dynamic focusing lens having a completely new mechanism that can be miniaturized and allow for a quick Response has been developed. This lens is structured to directly transform tie lens shape as crystalline lens of human eyes. The lens comprises two thin glass diaphragms as a refracting surface, transparent working fluid sealed between them, and a micro actuator. When the actuator is driven to push or pull the glass diaphragm at the actuator side, the other glass diaphragm is transformed into the lens shape (convex lens or concave lens) having various curvatures. The Dynamic focusing lens shows quick Response up to 150 Hz, because the lens does not have rotating nor sliding mechanism which are usually used in conventional focusing mechanism.
Takashi Kaneko - One of the best experts on this subject based on the ideXlab platform.
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Quick-Response Dynamic focusing lens using multilayered piezoelectric bimorph actuator
Micro-Opto-Electro-Mechanical Systems, 2000Co-Authors: Takashi Kaneko, N. Mitsumoto, Kohtaro Ohba, Nobuaki KawaharaAbstract:We present a new micro optical devices, Dynamic focusing lens (DFL) using a multi-layered piezoelectric bimorph micro actuator. DFL is structured to directly deform the lens shape as a crystalline lens of the human eye. The deformable lens is comprised of two thin glass diaphragms with a transparent working fluid sealed between them. The curvature of the lens shape is changed according to the applied voltage of the actuator. DFL shows quick Response up to 150 Hz for focal plane shift because the mass movement can be minimized compared with the conventional focusing method of moving a lens position. We also propose digital all-in-focus microscope system as an application of DFL. This system realizes real-time observation for micro parts assembling with a deep depth of field, as well as three-dimensional shape measurement using only one image sensor. In this paper, a newly developed real-time algorithm called one pixel method for generating clear image having a deep depth of field is described. This method is able to process one original picture (640 x 480 pixels per frame) in approximately 1.0ms. Results of three-dimensional shape measurement in high accuracy using the contrast of brightness method are also discussed.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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A compact and quick-Response Dynamic focusing lens
Sensors and Actuators A: Physical, 1998Co-Authors: Takashi Kaneko, Takuhiro Ohmi, Nobuyuki Ohya, Nobuaki KawaharaAbstract:Abstract A Dynamic focusing lens with a completely new mechanism that can be miniaturized and allows for a quick-Response has been developed. This lens is structured to directly transform the lens shape as a crystalline lens of the human eye. The lens is comprised of two thin glass diaphragms as a refracting surface, with a transparent working fluid sealed between them, and a new type of piezoelectric bimorph actuator. The displacement of the actuator is enlarged by the bimorph structure. The generated force is determined by the layer number of the bimorph cells. When the actuator is driven to push or pull the glass diaphragm at the actuator side, the other glass diaphragm is transformed into a lens shape (convex lens or concave lens) having various curvatures. The focal length of the lens is controlled by the applied voltage to the actuator. The Dynamic focusing lens shows quick Response up to 150 Hz. When the lens is operated over 60 Hz, human visual perception cannot recognize the change of the focal length, and we can observe many images having different focal lengths simultaneously.
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A new smart vision system using a quick-Response Dynamic focusing lens
Proceedings IEEE Thirteenth Annual International Conference on Micro Electro Mechanical Systems (Cat. No.00CH36308), 1Co-Authors: Takashi Kaneko, N. Mitsumoto, Nobuaki KawaharaAbstract:We propose a new smart vision system using a quick-Response Dynamic focusing lens suitable for micro parts assembling. This system realizes real-time observation for micro parts with a deep depth of field, as well as three-dimensional shape measurement using only one image sensor. In this paper, we report a newly developed real-time algorithm called the one pixel method for generating a clear image having a deep depth of field. This method is able to process one original picture (640/spl times/480 pixels per frame) in approximately 1.0 ms. We also report the results of three-dimensional shape measurement with high accuracy using the contrast of brightness method.
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A new, compact and quick-Response Dynamic focusing lens
Proceedings of International Solid State Sensors and Actuators Conference (Transducers '97), 1Co-Authors: Takashi Kaneko, Takuhiro Ohmi, Nobuyuki Ohya, Nobuaki Kawahara, T. HattoriAbstract:A Dynamic focusing lens having a completely new mechanism that can be miniaturized and allow for a quick Response has been developed. This lens is structured to directly transform tie lens shape as crystalline lens of human eyes. The lens comprises two thin glass diaphragms as a refracting surface, transparent working fluid sealed between them, and a micro actuator. When the actuator is driven to push or pull the glass diaphragm at the actuator side, the other glass diaphragm is transformed into the lens shape (convex lens or concave lens) having various curvatures. The Dynamic focusing lens shows quick Response up to 150 Hz, because the lens does not have rotating nor sliding mechanism which are usually used in conventional focusing mechanism.
Susanta Kumar Gauri - One of the best experts on this subject based on the ideXlab platform.
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Optimization of multi-Response Dynamic systems integrating multiple regression and Taguchi’s Dynamic signal-to-noise ratio concept
International Journal of Engineering Science and Technology, 2017Co-Authors: Surajit Pal, Susanta Kumar GauriAbstract:The principal difference between a Dynamic and a static system is that the former includes a signal factor for expressing the intended output while the later does not. Assuming a linear association exists between the Response and signal variables, Taguchi offered a two-stage route for optimizing a Dynamic system: maximize the Dynamic signal-to noise ratio (DSN) and then, change the gradient to the desired gradient by a suitable modification parameter. Some researchers have indicated limitations to Taguchi’s DSN analysis, and advocated alternative approaches for optimization of a Dynamic system. However, the Taguchi method as well as these alternative approaches is useful for optimizing a single-Response Dynamic system only. In realism, the majority of the contemporary manufacturing practices encompass numerous Response variables as well as industries demand for developing procedures for optimizing multi-Response Dynamic system. This paper proposes a novel procedure that integrates multiple regression (MR) technique and Taguchi’s DSN concept to optimize the multi-Response Dynamic system. In this method, appropriate multiple regression equations according to a chosen model for Dynamic system are fitted first based on the observed experimental data and then DSN (called MRDSN) for different Response variables are computed using the MRbased predicted values. Finally, weighted MRDSN is considered as the objective function for the optimization. The proposed procedure is investigated with respect to three modelling approaches for the Dynamic systems. The results of analysis reveal that the proposed procedure with Response modelling approach results in the best optimization performance. It also results in better optimization performance than back-propagation neural network-based approach and data mining-based approach reported by the past researchers. Keywords: multiple Responses, multiple regression, weighted Dynamic signal-to-noise ratio, performance measure modelling, Response function modelling, Response modelling, optimization
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Optimization of multi-Response Dynamic systems using multiple regression-based weighted signal-to-noise ratio
International Journal of Industrial Engineering Computations, 2017Co-Authors: Susanta Kumar Gauri, Surajit PalAbstract:A Dynamic system differs from a static system in that it contains signal factor and the target value depends on the level of the signal factor set by the system operator. The aim of optimizing a multi-Response Dynamic system is to find a setting combination of input controllable factors that would result in optimum values of all Response variables at all signal levels. The most commonly used performance metric for optimizing a multi-Response Dynamic system is the composite desirability function (CDF). The advantage of using CDF is that it is a simple unit less measure and it has a good foundation in statistical practice. However, the problem with the CDF is that it does not consider the variability of the individual Response variables. Moreover, if the specification limits for the Response variables are not provided the CDF cannot be computed. In this paper, a new performance metric for multi-Response Dynamic system, called multiple regression-based weighted signal-to-noise ratio (MRWSN) is proposed, which overcome the limitations of CDF. Two sets of experimental data on multi-Response Dynamic systems, taken from literature, are analysed using both CDF-based and the proposed MRWSN-based approaches for optimization. The results show that the MRWSN-based approach also results in substantially better optimization performance than the CDF-based approach
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Optimization of multi-Response Dynamic systems using principal component analysis (PCA)-based utility theory approach
international journal of industrial engineering computations, 2013Co-Authors: Susanta Kumar GauriAbstract:Article history: Received July 2 2013 Received in revised format September 7 2013 Accepted September 12 2013 Available online September 14 2013 Optimization of a multi-Response Dynamic system aims at finding out a setting combination of input controllable factors that would result in optimum values for all Response variables at all signal levels. In real life situation, often the multiple Responses are found to be correlated. The main advantage of PCA-based approaches is that it takes into account the correlation among the multiple Responses. Two PCA-based approaches that are commonly used for optimization of multiple Responses in Dynamic system are PCA-based technique for order preference by similarity to ideal solution (TOPSIS) and PCA-based multiple criteria evaluation of the grey relational model (MCE-GRM). This paper presents a new PCA-based approach, called PCA-based utility theory (UT) approach, for optimization of multiple Dynamic Responses and compares its optimization performance with other existing PCA-based approaches. The results show that the proposed PCA-based UT method is superior to the other PCA-based approaches. © 2013 Growing Science Ltd. All rights reserved
Sujata Tarafdar - One of the best experts on this subject based on the ideXlab platform.
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Effect of loading history on visco-elastic potato starch gel
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2016Co-Authors: Moutushi Dutta Choudhury, Shantanu Das, Sujata TarafdarAbstract:Abstract In this work gelatinised potato starch is shown to retain the memory of past loading history. It exhibits a visco-elastic Response which does not depend solely on instantaneous conditions. A simple squeeze flow experiment is performed, where loading is done in two steps with a time lag τ∼ seconds between the steps. The effect on the strain, of varying τ is reproduced by a three element visco-elastic solid model. Complexity is introduced through a generalised calculus approach by incorporating a non-integer order time derivative in the viscosity equation. A strain hardening proportional to the time lag between the two loading steps is also incorporated. This model reproduces the three salient features observed in the experiment, namely – the memory effect, slight initial oscillations in the strain as well as the long-time solid-like Response. Dynamic visco-elasticity of the sample is also reported.
Nobuyuki Ohya - One of the best experts on this subject based on the ideXlab platform.
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A compact and quick-Response Dynamic focusing lens
Sensors and Actuators A: Physical, 1998Co-Authors: Takashi Kaneko, Takuhiro Ohmi, Nobuyuki Ohya, Nobuaki KawaharaAbstract:Abstract A Dynamic focusing lens with a completely new mechanism that can be miniaturized and allows for a quick-Response has been developed. This lens is structured to directly transform the lens shape as a crystalline lens of the human eye. The lens is comprised of two thin glass diaphragms as a refracting surface, with a transparent working fluid sealed between them, and a new type of piezoelectric bimorph actuator. The displacement of the actuator is enlarged by the bimorph structure. The generated force is determined by the layer number of the bimorph cells. When the actuator is driven to push or pull the glass diaphragm at the actuator side, the other glass diaphragm is transformed into a lens shape (convex lens or concave lens) having various curvatures. The focal length of the lens is controlled by the applied voltage to the actuator. The Dynamic focusing lens shows quick Response up to 150 Hz. When the lens is operated over 60 Hz, human visual perception cannot recognize the change of the focal length, and we can observe many images having different focal lengths simultaneously.
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A new, compact and quick-Response Dynamic focusing lens
Proceedings of International Solid State Sensors and Actuators Conference (Transducers '97), 1Co-Authors: Takashi Kaneko, Takuhiro Ohmi, Nobuyuki Ohya, Nobuaki Kawahara, T. HattoriAbstract:A Dynamic focusing lens having a completely new mechanism that can be miniaturized and allow for a quick Response has been developed. This lens is structured to directly transform tie lens shape as crystalline lens of human eyes. The lens comprises two thin glass diaphragms as a refracting surface, transparent working fluid sealed between them, and a micro actuator. When the actuator is driven to push or pull the glass diaphragm at the actuator side, the other glass diaphragm is transformed into the lens shape (convex lens or concave lens) having various curvatures. The Dynamic focusing lens shows quick Response up to 150 Hz, because the lens does not have rotating nor sliding mechanism which are usually used in conventional focusing mechanism.
