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Extremum seeking micro-thermal-fluid control for active two-phase microelectronics cooling

TieJun Zhang, John T. Wen, Agung Julius, Yoav Peles, Michael K. Jensen
2010 49th IEEE Conference on Decision and Control (CDC)  
However, flow and thermal oscillations, frequently present in two-phase microchannel cooling, may severely compromise the cooling performance and system integrity.  ...  In this paper, we present an adaptive extremum seeking control law which first uses the wall temperature measurement to estimate the heat transfer coefficient, and then adjusts the flow rate to maximize  ...  This is a good candidate for the extremum seeking control, but g is not directly measurable.  ... 
doi:10.1109/cdc.2010.5717101 dblp:conf/cdc/ZhangWJPJ10 fatcat:gat3ycqttzbmpihtekyk4yfs6i

Model-Free Extremum Seeking Control of Bioprocesses: A Review with a Worked Example

Laurent Dewasme, Alain Vande Wouwer
2020 Processes  
Uncertainty is a common feature of biological systems, and model-free extremum-seeking control has proved a relevant approach to avoid the typical problems related to model-based optimization, e.g., time  ...  In this article, a review of the past and current trends in model-free extremum seeking is proposed with an emphasis on finding optimal operating conditions of bioprocesses.  ...  Another fast algorithm using proportional-integral phasor extremum seeking was proposed by [92] for W/H systems; its semi-global and practically asymptotical stability was shown.  ... 
doi:10.3390/pr8101209 fatcat:q4d5wcdt25ggdn6mhejjizpz64

Real-Time Optimization of Organic Rankine Cycle Systems by Extremum-Seeking Control

Andres Hernandez, Adriano Desideri, Clara Ionescu, Robin De Keyser, Vincent Lemort, Sylvain Quoilin
2016 Energies  
This idea is further extended using a perturbation-based extremum seeking (ES) algorithm to identify online the optimal evaporating temperature.  ...  Since it uses input/output models for prediction, it avoids the need for state estimators, making it a suitable tool for industrial applications.  ...  Acknowledgments: The results presented in this paper have been obtained within the frame of the project The Next Generation Organic Rankine Cycles (ORCNext, funded by the Institute for  ... 
doi:10.3390/en9050334 fatcat:yfwbayp6p5fnhfqb555p22y6km

Utilization of excitation signal harmonics for control of nonlinear systems

Kasper Vinther, Henrik Rasmussen, Roozbeh Izadi-Zamanabadi, Jakob Stoustrup
2012 2012 IEEE International Conference on Control Applications  
Producing a sufficient system model can be cumbersome and a new non-model based method for control of nonlinear systems with input/output maps exhibiting sigmoid function properties is therefore proposed  ...  An evaporator in a refrigeration system was used as example in the simulations, however, it is anticipated that the method is applicable in a wide variety of systems satisfying the sigmoid function properties  ...  Refrigeration systems normally operate by continuous vaporization and compression of refrigerant.  ... 
doi:10.1109/cca.2012.6402411 dblp:conf/IEEEcca/VintherRIS12a fatcat:7pspvovcyzbo5a2qpm2ykz3y5u

Real-time optimization of intermediate temperature for a cascade heat pump via extreme seeking

Wenyi Wang, Yaoyu Li
2019 Proceedings Name  
We propose to use the extremum seeking control as a modelfree real-time optimization strategy for efficient operation of cascaded heat pump.  ...  However, the increased complexity of cascade heat pump systems has presented great challenge for online optimization for the energy efficiency, as model based control/optimization methods incur costly  ...  Acknowledgements The authors are grateful of TLK-Thermo GmbH for their permission for access to TIL-Suite products, as well as their technical help.  ... 
doi:10.3384/ecp19157251 dblp:conf/modelica/WangL19 fatcat:xff5vtdmw5c7fi5wofktfhkgpe

Target Tracking in Clutter with Extremum Seeking Control for Adaptive Detection Thresholding

Seung Park, Taek Song
2019 Sensors  
In this paper, we propose a detection threshold control method using extremum seeking control in realistic environments. The extremum seeking control is a method used in complex nonlinear systems.  ...  We propose a new structure for extremum seeking control that is applicable to detection processes with nonlinear characteristics.  ...  This extremum seeking control is also used in ABS (anti-lock braking system) [16] , WECS (wind energy conversion system) [17] , and VCS (vapor compression system) [18] .  ... 
doi:10.3390/s19061386 fatcat:ls4xrkgfindwzd37hwu3j7wavm

A New Mixture Refrigerant for Space Heating Air Source Heat Pump: Theoretical Modelling and Performance Analysis

Xiangrui Kong, Yufeng Zhang, Jinzhe Nie
2018 Applied Sciences  
RHR-1 could be a reasonable refrigerant used in ASHP for space heating in North China.  ...  The performance of RHR-1 was analyzed and compared with commonly used refrigerants including R134a, R410A, R407C and R22 in terms of heating coefficient of performance (COP h ), compression ratio (CR)  ...  organic framework materials and its application in solid desiccant air conditioning system (No. 51708013).  ... 
doi:10.3390/app8040622 fatcat:zpjaw65gvfdxbm2av7xaqidjsa

2020 Index IEEE Transactions on Control Systems Technology Vol. 28

2020 IEEE Transactions on Control Systems Technology  
., +, TCST Jan. 2020 238-253 Proportional-Integral Extremum Seeking for Vapor Compression Systems.  ...  ., +, TCST Sept. 2020 1956-1963 Proportional-Integral Extremum Seeking for Vapor Compression Systems.  ...  Optimal Detection Schemes for Multiplicative Faults in Uncertain Systems With Application to Rolling Mill Processes. Li, L., +, 2432 -2444  ... 
doi:10.1109/tcst.2020.3047034 fatcat:iin2gzukmbadhbln2qf25c4v6a

Non stationary nucleation: the model with averaged velocity [article]

Victor Kurasov
2013 arXiv   pre-print
This model is based on the classical nucleation theory but considers also vapor depletion around the formed embryo.  ...  We seek for the maximum of Ψ. Since the integral in expression for Ψ can be approximately expressed in elementary functions, we have an algebraic expression which can be easily differentiated.  ...  The model Precisely speaking one has to consider all trajectories of motion for the embryo, then to construct the Green functions with corresponding intensity of the vapor consumption and then to integrate  ... 
arXiv:1302.5064v1 fatcat:76kmmzlxnbfuvhqyr7ex5nez4e

Model-Based Condenser Fan Speed Optimization of Vapor Compression Systems

Sebastian Angermeier, Christian Karcher
2020 Energies  
Therefore, the study provides a crucial input for set-point optimization and steady-state modeling of air-cooled vapor compression systems.  ...  Vapor compression systems (VCS) cover a wide range of applications and consume large amounts of energy.  ...  valve Vapor compression cycle Vapor compression system Appendix A Table A1 .  ... 
doi:10.3390/en13226012 fatcat:bgdhx63tgjalxah4ptbmv2djra

Air flow control based on optimal oxygen excess ratio in fuel cells for vehicles

Ai Guo, Weirong Chen, Qi Li, Zhixiang Liu, Haidan Que
2013 Journal of Modern Transportation  
Based on a fuel cell system model for vehicles, OER performance was analyzed for different stack currents and temperatures in this paper, and the results show that the optimal OER was affected weakly by  ...  Air flow control is one of the most important control methods for maintaining the stability and reliability of a fuel cell system, which can avoid oxygen starvation or oxygen saturation.  ...  They put forward a real-time extremum seeking control method. This control method is simple, and can achieve maximum power over the entire operating range.  ... 
doi:10.1007/s40534-013-0009-8 fatcat:ze7maqilnvbxtg43scotwbvwlq

Strain-tuned topological phase transition and unconventional Zeeman effect in ZrTe5 microcrystals [article]

Apurva Gaikwad, Song Sun, Peipei Wang, Liyuan Zhang, Jennifer Cano, Xi Dai, Xu Du
2022 arXiv   pre-print
Modulating band structure provides a tuning knob for the Berry phase, and in the extreme case drives a topological phase transition.  ...  We show that such a spin-dependent Berry phase, largely neglected in solid-state systems, is critical in modeling quantum oscillations in Dirac bands in topological materials.  ...  For systems with nontrivial Berry curvature, the Berry phase splitting φ s along the Fermi surface will be nonzero.  ... 
arXiv:2201.04049v1 fatcat:md76r3kwanc7fkobej43iozcqq

Energy balance climate models

Gerald R. North, Robert F. Cahalan, James A. Coakley
1981 Reviews of Geophysics  
A linear stability theorem and a complete nonlinear stability analysis for the models are developed.  ...  Analytical solutions are also obtained for the linearized models driven by stochastic forcing elements.  ...  The system (46) forms a Sturm-Liouville system [Courant and Hilbert, 1953] , provided D(x) > 0 and is well behaved. The fn(X) are proportional to Pn(X) for D --const.  ... 
doi:10.1029/rg019i001p00091 fatcat:4h7gfqxc2jdcbdrmnpd7z2rsji

Phase field theory of crystal nucleation in hard sphere liquid

László Gránásy, Tamás Pusztai, Gyula Tóth, Zoltán Jurek, Massimo Conti, Bjørn Kvamme
2003 Journal of Chemical Physics  
Lett. 88, 206105 (2002)] is applied for nucleation in hard--sphere liquids. The exact thermodynamics from molecular dynamics is used.  ...  The interface thickness for phase field is evaluated from the cross--interfacial variation of the height of the singlet density peaks.  ...  This is then the Legendre transformation that yields the grand potential, Ω = F − µ ∞ N , i.e., we seek the extremum of the grand potential functional.  ... 
doi:10.1063/1.1618213 fatcat:6abmjrb5araq3in6oeqdg4unmu

Control of fuel cell breathing

2004 IEEE Control Systems  
F uel cell systems offer clean and efficient energy production and are currently under intensive development by several manufacturers for both stationary and mobile applications.  ...  For example, a methanol FC powertrain has an energy density of about 1,900 Wh/kg, whereas a lead acid battery provides 40 Wh/kg [4] .  ...  Yang of the Ford Motor Company for providing data on a vehicle FC system. We wish to thank C. Jacobson and S. Bortoff of the United Technology Research Center for their encouragement.  ... 
doi:10.1109/mcs.2004.1275430 fatcat:hudcgyi3fbektjvjb3eny6a7em
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