Enhancement of SPSA algorithm performance using reservoir quality maps: Application to coupled well placement and control optimization problems

2020 ◽  
Vol 189 ◽  
pp. 106984 ◽  
Author(s):  
Behzad Pouladi ◽  
Abdorreza Karkevandi-Talkhooncheh ◽  
Mohammad Sharifi ◽  
Shahab Gerami ◽  
Alireza Nourmohammad ◽  
...  
Author(s):  
Mohammad Salehian ◽  
Morteza Haghighat Sefat ◽  
Khafiz Muradov

Author(s):  
Hosam K. Fathy ◽  
Panos Y. Papalambros ◽  
A. Galip Ulsoy

The plant and control optimization problems are coupled in the sense that solving them sequentially does not guarantee system optimality. This paper extends previous studies of this coupling by relaxing their assumption of full state measurement availability. An original derivation of first-order necessary conditions for plant, observer, controller, and combined optimality furnishes coupling terms quantifying the underlying trilateral coupling. Special scenarios where the problems decouple are pinpointed, and a nested optimization strategy that guarantees system optimization strategy that guarantees system optimality is adopted otherwise. Applying these results to combined passive/active car suspension optimization produces a suspension design outperforming its passive, active, and sequentially optimized passive/active counterparts.


2017 ◽  
Vol 101 ◽  
pp. 193-209 ◽  
Author(s):  
Yang Zhang ◽  
Ranran Lu ◽  
Fahim Forouzanfar ◽  
Albert C. Reynolds

Author(s):  
Hosam K. Fathy ◽  
Scott A. Bortoff ◽  
G. Scott Copeland ◽  
Panos Y. Papalambros ◽  
A. Galip Ulsoy

This paper studies the combined optimization of an elevator’s design (plant) and LQG controller for ride comfort. Elevator dynamics and primary vibration sources (drive motor torque ripple and guide rail irregularity) are modeled using an object-oriented language. The resulting model is nonlinear. Elevator vibrations are minimized with respect to both the design and the LQG controller. LQG gains are scheduled versus cab mass and height for robustness. Sequential plant/control optimization produces an optimal ride only when the torque ripple is the dominant disturbance. Otherwise, passive vibration reduction decreases the controller’s authority over the vibrations, hence coupling the plant and control optimization problems. Combined plant/controller optimization, using a nested strategy, mitigates this coupling and finds the correct optimal system design.


2017 ◽  
Vol 63 (6) ◽  
pp. 926-932
Author(s):  
Lyudmila Belskaya ◽  
Viktor Kosenok ◽  
Ж. Массард

So far optimization problems for diagnostics and prognostication aids remained relevant for lung cancer as a leader in the structure of cancers. Objective: a search for regularities of changes in the saliva enzyme activity in patients with nonsmall cell lung cancer. In the case-control study, 505 people took part, divided into 2 groups: primary (lung cancer, n=290) and control (conventionally healthy, n=215). All the participants went through a questionnaire survey, saliva biochemical counts, and a histological verification of their diagnosis. The enzyme activity was measured with spectrophotometry. Between-group differences were measured with the nonparametric test. It was shown that in terms of lung cancer, we observe metabolic changes, described with the decreased de Ritis coefficient (p


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