Filters
Results 1 - 10 of 56946
Results 1 - 10 of 56946.
Search took: 0.061 seconds
Sort by: date | relevance |
AbstractAbstract
[en] The study of infinite-horizon nonstationary dynamic programs using the operator approach is continued. The point of view here differs slightly from that taken by others, in that Denardo's local income function is not used as a starting point. Infinite-horizon values are defined as limits of finite-horizon values, as the horizons get long. Two important conditions of an earlier paper are weakened, yet the optimality equations, the optimality criterion, and the existence of optimal ''structured'' strategies are still obtained
Primary Subject
Record Type
Journal Article
Journal
Journal of Optimization Theory and Applications; ISSN 0022-3239;
; v. 36(3); p. 419-432

Country of publication
Publication YearPublication Year
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] An application of the linear optimal control theory to the problem of load follow control in pressurized water reactors (PWR) is investigated. In order to perform the steady-state and load follow operation in PWR, a nonlinear model for the reactor and steam generator is derived and linearized at 50% rated power. Simulation tests are performed for 10% demanded load. Comparing the dynamic response of the newly developed optimal load follow controller with those of the integral error feedback controller proposed by Yang, the rise time of dynamic response of the former is about 15 seconds faster than those of the latter, thus the results indicate that the fast response of the optimal load follow controlled is verified. The results of this work are directly applicable to the design of the load control systems for commercially operated PWRs. (Author)
Primary Subject
Record Type
Journal Article
Journal
Transactions of the Korean Institute of Electrical Engineers; CODEN CHNOD; v. 34(12); p. 491-497
Country of publication
Publication YearPublication Year
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Sun, Chen; Saxena, Avadh; Sinitsyn, Nikolai A, E-mail: chen.sun.whu@gmail.com, E-mail: avadh@lanl.gov, E-mail: nsinitsyn@lanl.gov
AbstractAbstract
[en] We propose nearly optimal control strategies for changing the states of a quantum system. We argue that quantum control optimization can be studied analytically within some protocol families that depend on a small set of parameters for optimization. This optimization strategy can be preferred in practice because it is physically transparent and does not lead to combinatorial complexity in multistate problems. As a demonstration, we design optimized control protocols that achieve switching between orthogonal states of a naturally biased quantum two-level system. (paper)
Primary Subject
Source
Available from http://dx.doi.org/10.1088/1361-6455/aa807d; Country of input: International Atomic Energy Agency (IAEA)
Record Type
Journal Article
Journal
Journal of Physics. B, Atomic, Molecular and Optical Physics; ISSN 0953-4075;
; CODEN JPAPEH; v. 50(17); [8 p.]

Country of publication
Publication YearPublication Year
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] In this paper we are concerned with the optimal control for a class of systems governed by the eigen-equation: Lphi + sigma phi = (1/lambda) K phi where the state (lambda(sigma), phi(sigma)) is the dominate eigenvalue of the operator (L + sigma)-1 K and its corresponding eigenfunction. Under the variance index, we show the existence and the uniqueness of optimal control and give the corresponding optimality conditions. Finally the obtained general results are applied to the power factor optimization for a nuclear reactor
Primary Subject
Record Type
Journal Article
Journal
Journal de Mathematiques Pures et Appliquees; ISSN 0021-7824;
; v. 63(2); p. 169-186

Country of publication
Publication YearPublication Year
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Galenko, Alexander; Popova, Elmira; Kee, Ernie; Grantom, Rick
The ASME Foundation, Inc., Three Park Avenue, New York, NY 10016-5990 (United States)
The ASME Foundation, Inc., Three Park Avenue, New York, NY 10016-5990 (United States)
AbstractAbstract
[en] We analyze a system of N components with dependent failure times. The goal is to obtain the optimal block replacement interval (different for each component) over a finite horizon that minimizes the expected total maintenance cost. In addition, we allow each preventive maintenance action to change the future joint failure time distribution. We illustrate our methodology with an example from South Texas Project Nuclear Operating Company. (authors)
Primary Subject
Source
2006; 7 p; American Society of Mechanical Engineers - ASME; New York (United States); 14. international conference on nuclear engineering (ICONE 14); Miami, FL (United States); 17-20 Jul 2006; Country of input: France
Record Type
Book
Literature Type
Conference
Country of publication
Publication YearPublication Year
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Kong Shulan; Zhang Huanshui; Zhang Zhaosheng, E-mail: shulankong@sina.com
AbstractAbstract
[en] In this Letter, power control problem is firstly studied at an angle of LQG measurement-feedback control problem. A stochastic uplink power control problem is considered for CDMA systems. An effective distributed algorithm is proposed based on stochastic linear quadratic optimal control theory assuming SIR measurements contain white noise. The presented scheme minimizes the sum of the power and the error of SIR. A measurement-feedback power controller is designed by constructing an optimization problem of a stochastic linear quadratic type in Krein space and solving the Kalman filter problem for the systems
Primary Subject
Source
S0375-9601(06)01512-X; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Record Type
Journal Article
Journal
Country of publication
Publication YearPublication Year
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] Quantum optimal control experiments and simulations have successfully manipulated the dynamics of systems ranging from atoms to biomolecules. Surprisingly, these collective works indicate that the effort (i.e., the number of algorithmic iterations) required to find an optimal control field appears to be essentially invariant to the complexity of the system. The present work explores this matter in a series of systematic optimizations of the state-to-state transition probability on model quantum systems with the number of states N ranging from 5 through 100. The optimizations occur over a landscape defined by the transition probability as a function of the control field. Previous theoretical studies on the topology of quantum control landscapes established that they should be free of suboptimal traps under reasonable physical conditions. The simulations in this work include nearly 5000 individual optimization test cases, all of which confirm this prediction by fully achieving optimal population transfer of at least 99.9% on careful attention to numerical procedures to ensure that the controls are free of constraints. Collectively, the simulation results additionally show invariance of required search effort to system dimension N. This behavior is rationalized in terms of the structural features of the underlying control landscape. The very attractive observed scaling with system complexity may be understood by considering the distance traveled on the control landscape during a search and the magnitude of the control landscape slope. Exceptions to this favorable scaling behavior can arise when the initial control field fluence is too large or when the target final state recedes from the initial state as N increases.
Primary Subject
Secondary Subject
Source
(c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Record Type
Journal Article
Journal
Country of publication
Publication YearPublication Year
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] These are lecture notes of the introductory course in Optimal Control theory treated from the geometric point of view. Optimal Control Problem is reduced to the study of controls (and corresponding trajectories) leading to the boundary of attainable sets. We discuss Pontryagin Maximum Principle, basic existence results, and apply these tools to concrete simple optimal control problems. Special sections are devoted to the general theory of linear time-optimal problems and linear-quadratic problems. (author)
Primary Subject
Source
Agrachev, A.A. (ed.) (Steklov Mathematical Institute, Moscow (Russian Federation); SISSA, Trieste (Italy)); Abdus Salam International Centre for Theoretical Physics, Trieste (Italy); 774 p; ISBN 92-95003-11-X;
; Jul 2002; p. 452-513; School on mathematical control theory; Trieste (Italy); 3-28 Sep 2001; LNS--028008; Also available online: http://www.ictp.it; 6 refs

Record Type
Report
Literature Type
Conference
Report Number
Country of publication
Publication YearPublication Year
Reference NumberReference Number
Related RecordRelated Record
INIS VolumeINIS Volume
INIS IssueINIS Issue
External URLExternal URL
Lee, Kyoung Ho; Lee, Sang Ryoul; Choi, Byoung Youn; Kwon, Seong Chul
Proceedings of the KSME 2001 spring annual meeting D
Proceedings of the KSME 2001 spring annual meeting D
AbstractAbstract
[en] This paper describes an optimal scheduling for ice slurry systems for energy cost saving. The optimization technique applied in the study is the dynamic programming method, for which the state variable is the storage in the ice storage tank and the control variable is the state of chiller's on-off switching. Though the costs during charge period is included in optimization by taking the average cost of ice per hour for slurry making, the time horizon for the simulation is limited building cooling period because accurate charge rate from the ice maker into the ice storage tank cannot be estimated during the charge period. In the operating simulation after optimizing procedure, energy consumption and operating cost for the optimal control are calculated and compared with them for a conventional control with one case of cooling load profile
Primary Subject
Source
The Korean Society of Mechanical Engineers, Seoul (Korea, Republic of); 1019 p; 2001; p. 286-291; KSME 2001 spring annual meeting D; Cheju (Korea, Republic of); 27-29 Jun 2001; Available from KSME, Seoul (KR); 2 refs, 8 figs, 3 tabs
Record Type
Miscellaneous
Literature Type
Conference
Country of publication
Publication YearPublication Year
Reference NumberReference Number
Related RecordRelated Record
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] Optimal motion for a robot manipulator is obtained by nonlinear programming. The objective of optimal motion is minimizing energy consumption of manipulator arm with fixed traveling time in the presence of obstacles. The geometric path is not predetermined. The total trajectory is described in terms of cubic B-spline polynomials and the coefficients of them are obtained to minimize a specific performance index. Obstacle avoidance is performed by the method that the square sum of penetration growth distances between every obstacles and robot links is included in the performance index with appropriate weighting coefficient. In all examples tested here, the solutions were converged to unique optimal trajectories from different initial ones. The optimal geometric path obtained in this research can be used in minimum time trajectory planning. (author)
Primary Subject
Record Type
Journal Article
Journal
Transactions of the Korean Society of Mechanical Engineers. A; ISSN 1226-4873;
; v. 21(4); p. 596-610

Country of publication
Publication YearPublication Year
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
1 | 2 | 3 | Next |