The Experts below are selected from a list of 28647 Experts worldwide ranked by ideXlab platform
Seiji Chonan - One of the best experts on this subject based on the ideXlab platform.
-
a closed loop transcutaneous power transmission system with thermal control for artificial urethral valve driven by sma actuator
Journal of Intelligent Material Systems and Structures, 2006Co-Authors: Mami Tanaka, Kazuhiro Abe, Feng Wang, Haruo Nakagawa, Yoichi Arai, Seiji ChonanAbstract:This article presents the development of an implanted artificial urethral valve that is used for the treatment of urinary incontinence, with emphasis on a transcutaneous power transmission system with closed-loop thermal control function. The valve uses a shape memory alloy (SMA) plate as the actuator, which is activated with batteries placed outside a patient’s body using a transcutaneous power transmission system. The power transmission system is equipped with an implanted Temperature monitor circuit and a Temperature Controller to prevent the SMA actuator from being overheated during a prolonged urination. Laboratory experiments and animal experiments, both in vitro and in vivo, show that the developed power transmission system can successfully control the Temperature of the SMA actuator to activate the valve without excessive heating of the SMA actuator.
Serkan Kincal - One of the best experts on this subject based on the ideXlab platform.
-
Model based Temperature Controller development for water cooled PEM fuel cell systems
International Journal of Hydrogen Energy, 2015Co-Authors: Yasemin Saygili, Inci Eroglu, Serkan KincalAbstract:PEM (proton exchange membrane) fuel cell operation necessitates thermal management to satisfy the requirements of safe and efficient operation by keeping the Temperature within a certain range independent of varying load conditions. Heat generation within the fuel cell changes according to the power delivered from the stack, requiring a dynamic control system to remove this excess heat and maintain the desired stack Temperature. In this study, a closed loop water circulation strategy is considered and evaluated for cooling a 3 kW PEM fuel cell. The cooling system consists of a water circulation pump and a radiator coupled to a fan, integrated with the fuel cell stack. A first principles based model is developed for the integrated cooling system through an energy balance containing the relevant terms. A sequence of dynamic tests is performed on the cooling system to identify the parameters appearing in the model developed. The resulting semi-empirical model is used to evaluate possible control strategies managing the cooling loop. Three specific strategies are analyzed and the performances of these Controllers are evaluated in terms of stack Temperature, integral time weighted absolute error (ITAE) and the parasitic energy requirements. Minimizing fan usage with an on/off Controller while keeping the pump voltage as a continuously manipulated variable through a feedback PI (proportional-integral) Controller delivers the best results. The MATLAB-SIMULINK® platform is used in the development and implementation of the models and Controllers. In our strategy, the characterization of the cooling loop is physically de-coupled from the development of the fuel cell stack - allowing for the evaluation of candidate equipment and algorithms prior to the fuel cell stack being available, which is often the case during prototype development.
Paisan Kittisupakorn - One of the best experts on this subject based on the ideXlab platform.
-
product quality improvement of batch crystallizers by a batch to batch optimization and nonlinear control approach
Chemical Engineering Journal, 2008Co-Authors: Woranee Paengjuntuek, Amornchai Arpornwichanop, Paisan KittisupakornAbstract:Batch crystallization is one of the widely used processes for separation and purification in many chemical industries. Dynamic optimization of such a process has recently shown the improvement of final product quality in term of a crystal size distribution (CSD) by determining an optimal operating policy. However, under the presence of unknown or uncertain model parameters, the desired product quality may not be achieved when the calculated optimal control profile is implemented. In this study, a batch-to-batch optimization strategy is proposed for the estimation of uncertain kinetic parameters in the batch crystallization process, choosing the seeded batch crystallizer of potassium sulfate as a case study. The information of the CSD obtained at the end of batch run is employed in such an optimization-based estimation. The updated kinetic parameters are used to modify an optimal operating Temperature policy of a crystallizer for a subsequent operation. This optimal Temperature policy is then employed as new reference for a Temperature Controller which is based on a generic model control algorithm to control the crystallizer in a new batch run.
Robert G Landers - One of the best experts on this subject based on the ideXlab platform.
-
melt pool Temperature control for laser metal deposition processes part i online Temperature control
Journal of Manufacturing Science and Engineering-transactions of The Asme, 2010Co-Authors: Lie Tang, Robert G LandersAbstract:Melt pool Temperature is of great importance to deposition quality in laser metal deposition processes. To control the melt pool Temperature, an empirical process model describing the relationship between the Temperature and process parameters (i.e., laser power, powder flow rate, and traverse speed) is established and verified experimentally. A general tracking Controller using the internal model principle is then designed. To examine the Controller performance, three sets of experiments tracking both constant and time-varying Temperature references are conducted. The results show the melt pool Temperature Controller performs well in tracking both constant and time-varying Temperature references even when process parameters vary significantly. However a multilayer deposition experiment illustrates that maintaining a constant melt pool Temperature does not necessarily lead to uniform track morphology which is an important criteria for deposition quality. The reason is believed to be that different melt pool morphologies may have the same Temperature depending on the dynamic balance of heat input and heat loss.
-
melt pool Temperature modeling and control for laser metal deposition processes
American Control Conference, 2009Co-Authors: Lie Tang, Robert G LandersAbstract:Melt pool Temperature is of great importance to deposition quality in Laser Metal Deposition processes. To control the melt pool Temperature, an empirical process model describing the relation between the Temperature and laser power, powder flow rate, and traverse speed is established and verified experimentally. A general tracking Controller using the Internal Model Principle is then designed. To examine the Controller performance, two experiments tracking a constant Temperature reference and a time varying reference are conducted. The results are compared to open-loop experiments where the laser power profile is derived directly from the model. The results show the melt pool Temperature Controller performs well in tracking both constant and time varying references and that the closed-loop control system greatly reduces the tracking errors.
Mami Tanaka - One of the best experts on this subject based on the ideXlab platform.
-
a closed loop transcutaneous power transmission system with thermal control for artificial urethral valve driven by sma actuator
Journal of Intelligent Material Systems and Structures, 2006Co-Authors: Mami Tanaka, Kazuhiro Abe, Feng Wang, Haruo Nakagawa, Yoichi Arai, Seiji ChonanAbstract:This article presents the development of an implanted artificial urethral valve that is used for the treatment of urinary incontinence, with emphasis on a transcutaneous power transmission system with closed-loop thermal control function. The valve uses a shape memory alloy (SMA) plate as the actuator, which is activated with batteries placed outside a patient’s body using a transcutaneous power transmission system. The power transmission system is equipped with an implanted Temperature monitor circuit and a Temperature Controller to prevent the SMA actuator from being overheated during a prolonged urination. Laboratory experiments and animal experiments, both in vitro and in vivo, show that the developed power transmission system can successfully control the Temperature of the SMA actuator to activate the valve without excessive heating of the SMA actuator.
