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Hybrid optimization method with general switching strategy for parameter estimation

Eva Balsa-Canto, Martin Peifer, Julio R Banga, Jens Timmer, Christian Fleck
2008 BMC Systems Biology  
Results: In this work we propose a new hybrid global method, based on the combination of an evolutionary search strategy with a local multiple-shooting approach, which offers a reliable and efficient alternative  ...  Because multiple-shooting avoids possible spurious solutions in the vicinity of the global optimum it often outperforms the frequently used initial value approach (single-shooting).  ...  Acknowledgements This work was supported by the European Community as part of the FP6 COSBICS Project (STREP FP6-512060), the German Federal Ministry of Education and Research, BMBF-project FRISYS (grant  ... 
doi:10.1186/1752-0509-2-26 pmid:18366722 pmcid:PMC2373877 fatcat:z5lcqxpnvff4fcppcn6yo4huue

Combining Direct and Indirect Methods in Optimal Control: Range Maximization of a Hang Glider [chapter]

Roland Bulirsch, Edda Nerz, Hans Josef Pesch, Oskar von Stryk
1993 Optimal Control  
Proceeding in this way, the high accuracy and reliability of the multiple shooting method, especially the precise computation of the switching structure and the possibility to verify many necessary conditions  ...  When solving optimal control problems, indirect methods such as multiple shooting suffer from difficulties in finding an appropriate initial guess for the adjoint variables.  ...  Acknowledgements This research was supported by the German National Science Foundation (Deutsche Forschungsgemeinschaft) through the Sondcrforschungsbereich 255 (Transatmosphiirische Flugsysteme)  ... 
doi:10.1007/978-3-0348-7539-4_20 fatcat:nrzk34ebvrcirhlhwmbrne64wi

Switching frequency control method based on short prediction horizon control algorithm of Quasi-Z source inverter

Shengchao Li, Sile Ma, Xiaojing Ma, Xiangyuan Jiang, Shuai Li
2018 International Journal of Robotics and Control  
In the proposed algorithm the optimal vector is selected based on the historical switching state.  ...  In order to overcome the problem of large inductance current ripple and poor output current quality caused by lower switching frequency in model predictive control (MPC).  ...  The traditional PI control method have a good control effect on the system, but a separate controller needs to be designed, and in order to be able to control the multiple variables simultaneously, which  ... 
doi:10.5430/ijrc.v2n1p1 fatcat:5tkhssamabfsxfyhmxuwnsq7sq

Time-optimal control of automobile test drives with gear shifts

Christian Kirches, Sebastian Sager, Hans Georg Bock, Johannes P. Schlöder
2010 Optimal control applications & methods  
Using the direct multiple shooting method we solve the reformulated benchmark problem for two cases: (a) As proposed in (Optim. Contr. Appl.  ...  For the second case we optimize the switching times and propose to use an initialization based on the solution of (a). Compared with (Optim. Contr. Appl.  ...  ACKNOWLEDGEMENTS Financial help for one of the authors within the SIMUMAT Project S-050/ESP-0158 in the PRICIT program of the CAM in Spain is gratefully acknowledged.  ... 
doi:10.1002/oca.892 fatcat:vxut6btvovhyxekvmwijhaczwe

Implementation of multicarrier PWM based 7-level Z-source cascaded H-bridge inverter

Palanisamy Ramasamy, Vidyasagar Sugavanam, Kalyanasundaram Vakesan, Subbulakshmy Ramamurthi, Selvakumar Kuppusamy, Usha Sengamalai, Thamizh Thentral
2022 International Journal of Power Electronics and Drive Systems (IJPEDS)  
MC-PWM technique is developed to generate switching pulses for Z-source inverter; it leads to boost the inverter output voltage with help of shoot through mode of operation.  ...  This proposed system provides reduced total harmonic distortion, improved stepped output voltage and current, nearly sinusoidal output voltage and reduced voltage stress across the switching devices.  ...  The MC-PWM is developed to control the multiple switching devices of 7-level cascaded H-bridge inverter, where its essential to preserve the shoot through proportion as stable.  ... 
doi:10.11591/ijpeds.v13.i1.pp322-329 fatcat:jvlgoqcna5b3fhmlll5ykflmo4

Initialization Concepts for Optimal Control of Hybrid Systems

Benjamin Passenberg, Magnus Kröninger, Georg Schnattinger, Marion Leibold, Olaf Stursberg, Martin Buss
2011 IFAC Proceedings Volumes  
However, the precision of the solution with the indirect method achieved in the first approach is higher. The two concepts are compared in a numerical example.  ...  In the first approach, the hybrid optimal control problem is solved by a direct method until the precision is sufficient for a successful initialization of the indirect method.  ...  indirect multiple shooting method.  ... 
doi:10.3182/20110828-6-it-1002.03012 fatcat:4t3jj3i2gncbrf47exia7eteum

Abort landing in the presence of windshear as a minimax optimal control problem, part 2: Multiple shooting and homotopy

R. Bulirsch, F. Montrone, H. J. Pesch
1991 Journal of Optimization Theory and Applications  
This boundary-value proNem is especially well suited for numerical treatment by the multiple shooting method.  ...  of user's guide for the solution of complicated real-life optimal control problems by multiple shooting.  ...  Multiple Shooting The multiple shooting method requires a fixed subdivision of the time interval which has to be chosen by the user, 0=:h<t2<" • "<tm:=tf, (5) with tj¢ rk, j = 1 ..... m and k = 1 ...  ... 
doi:10.1007/bf00940625 fatcat:fqaojqieyzcdtfprsstmkhsb5a

Complex differential games of pursuit-evasion type with state constraints, part 2: Numerical computation of optimal open-loop strategies

M. H. Breitner, H. J. Pesch, W. Grimm
1993 Journal of Optimization Theory and Applications  
These problems can be solved very efficiently and accurately by the well-known multiple-shooting method.  ...  In particular, saddle-point trajectories on the barrier are computed and discussed.  ...  Multiple Shooting Method The multiple shooting method is an efficient and reliable method for the numerical solution of multipoint boundary-value problems of the following form: ( Go(z('c ) ), 2(z)=G(z  ... 
doi:10.1007/bf00939877 fatcat:ut4qvvfo2zaddhrjrueiteibhu

Xth Person View Video for Observation from Diverse Perspectives

Naoki Shimura, Hidehiko Shishido, Yoshinari Kameda, Kenji Suzuki, Itaru Kitahara
2018 2018 Joint 7th International Conference on Informatics, Electronics & Vision (ICIEV) and 2018 2nd International Conference on Imaging, Vision & Pattern Recognition (icIVPR)  
Observation from various perspectives is achieved by properly switching "Outside-In images" captured from the outside to the inside of the target scene and "Inside-Out images" captured from the inside  ...  To generate Outside-In video, we use the Bullet-Time video technique, which presents images by switching multipleviewpoint videos based on the capturing camera alignment.  ...  In this method, in addition to Outside-In cameras placed surrounding the subject to understand the situation of the shooting space, we use Inside-Out cameras that are omnidirectional and placed inside  ... 
doi:10.1109/iciev.2018.8641024 fatcat:dw4ncnvslzbbzeq7xwi5ivhfr4

An adaptive algorithm for solving stochastic multi-point boundary value problems

Ali Foroush Bastani, Davood Damircheli
2016 Numerical Algorithms  
This paper presents an adaptive multiple-shooting method to solve stochastic multi-point boundary value problems.  ...  Having obtained the mesh points, we solve the underlying stochastic differential equation on each shooting interval with a first-order strongly-convergent stochastic Runge-Kutta method.  ...  in the field to devise methods of high accuracy and efficiency with low computational Table 5 : Comparing the accuracy of the fixed-step multiple-shooting and adaptive multiple-shooting methods.  ... 
doi:10.1007/s11075-016-0189-5 fatcat:hez3lv3r6jdshjj4ia3inb5xde

Sine Carrier for Fundamental Fortification in Three Phase Z-Source PWM Inverters

Shajith Ali
2009 Modern Applied Science  
The sine carrier PWM enhances the fundamental output voltage while keeping the total harmonic distortion lower without involving changes in device switching loss.  ...  The proposed sine carrier method, which uses the conventional sinusoidal reference signal and a sine carrier, has a better harmonic spectrum and a higher fundamental component compared to the conventional  ...  In addition to the eight traditional switching states, the Z-source inverter has several shoot-through zero states, during which both the upper and lower switches of one or multiple same phase legs are  ... 
doi:10.5539/mas.v4n1p73 fatcat:6ctfthshtbgeblb7tiixfond7a

CASCADED Z-SOURCE ISOLATED DC-DC CONVERTER WITH PWM SHOOT THROUGH CONTROL METHODS

Nimrah Saeed, Anas ibrar, Huma Hafeez, Lubna Majeed
2019 International Journal of Engineering Applied Sciences and Technology  
To describe operating principle three different PWM control methods are used to insert shoot through state in CZIDC.  ...  In this paper a novel topology named Cascaded Z-source Isolated DC-DC Converter (CZIDC) is proposed.  ...  During shoot through state, a switch is used to shorten output terminals of network, which reverse-bias the diode in impedance network.  ... 
doi:10.33564/ijeast.2019.v04i02.009 fatcat:fyfi6lmvjfas5l5pqxgn4stc4i

Numerical computation of singular control functions in trajectory optimization problems

HANS JOACHIM OBERLE
1990 Journal of Guidance Control and Dynamics  
3 The special code BOUNDSCO is an exten- sion of the ordinary multiple-shooting method in the sense that it was developed for the solution of boundary-value prob- lems with switching conditions.  ...  with switching conditions, we use a multiple-shoot- ing technique.'?  ... 
doi:10.2514/3.20529 fatcat:2gclexjdkzeqtau4lxrmk5ywu4

Direct and indirect methods for trajectory optimization

O. von Stryk, R. Bulirsch
1992 Annals of Operations Research  
For this a special direct collocation method is presented. In a hybrid approach this direct method can be used in combination with multiple shooting.  ...  To improve the low accuracy of the direct methods and to increase the convergence areas of the indirect methods we suggest a hybrid approach.  ...  of the multiple shooting method (-).  ... 
doi:10.1007/bf02071065 fatcat:hdfmfvxntfgh3je24uvzhzlogu

MATLAB Implementation of Direct and Indirect Shooting Methods to Solve an Optimal Control Problem With State Constraints

Andrzej Karbowski
2021 Journal of Automation, Mobile Robotics & Intelligent Systems  
It is based on using in turn two multiple shooting BVP approaches: direct and indirect.The paper is supplementary to the earlier author's paper on direct and indirect shooting methods, presenting the theory  ...  Itis used in the case, when the simple time discretization of the state equations and expressing the optimal control problem as a nonlinear mathematical programming problem is too coarse.  ...  The basic idea of the numerical treatment of such problems by multiple shooting technique is to consider the switching conditions as boundary conditions to be satis�ied at some interior multiple shooting  ... 
doi:10.14313/jamris/1-2021/6 fatcat:epbrwq342fe7pddttr3eivoigq
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