Academic literature on the topic 'Sensitivity of optimum control'

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Journal articles on the topic "Sensitivity of optimum control"

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Kajiwara, Itsurou, and Akio Nagamatsu. "Simultaneous optimum design of structure and control systems by sensitivity analysis." Finite Elements in Analysis and Design 14, no. 2-3 (October 1993): 187–95. http://dx.doi.org/10.1016/0168-874x(93)90019-m.

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Craven, B. D. "Optimal control on an infinite domain." ANZIAM Journal 47, no. 2 (October 2005): 143–53. http://dx.doi.org/10.1017/s1446181100009950.

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AbstractFor an optimal control problem with an infinite time horizon, assuming various terminal state conditions (or none), terminal conditions for the costate are obtained when the state and costate tend to limits with a suitable convergence rate. Under similar hypotheses, the sensitivity of the optimum to small perturbations is analysed, and in particular the stability of the optimum when the infinite horizon is truncated to a large finite horizon. An infinite horizon version of Pontryagin's principle is also obtained. The results apply to various economic models.
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Jalili, Nader, and Nejat Olgac. "A Sensitivity Study on Optimum Delayed Feedback Vibration Absorber." Journal of Dynamic Systems, Measurement, and Control 122, no. 2 (August 10, 1998): 314–21. http://dx.doi.org/10.1115/1.482457.

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A sensitivity analysis is presented for a novel tuned vibration absorber. The active tuning of the absorber is achieved using partial state feedback with a controlled time delay. The final structure, which is named Delayed Feedback Vibration Absorber (DFVA), is optimized to yield minimum Mpeak of the primary system involved for a given wide band of excitation frequencies. The optimization is performed over the absorber’s structural properties and the feedback control parameters. An optimal tuning over optimally designed passive absorber is conducted first, and separately a collective optimization over both the absorber structure and the control is studied. The assurance of the stability of the time-delayed system, which forms a critical constraint on the optimization, is also discussed. Regardless of the nature of the optimal operation, the parametric variations in the structure can influence the vibration absorption performance significantly. This concern is addressed via a sensitivity analysis. Primarily, the variations on the absorber stiffness and damping properties are studied. The findings of this effort provide tools for determining the acceptable tolerance limits of the absorber properties. [S0022-0434(00)02202-4]
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KAJIWARA, Itsurou, Tohru INAGAKI, and Akio NAGAMATSU. "Optimum Design of Vibration Control System using Modal Analysis and Sensitivity Analysis." Transactions of the Japan Society of Mechanical Engineers Series C 58, no. 552 (1992): 2365–72. http://dx.doi.org/10.1299/kikaic.58.2365.

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Xue, S. D., J. M. Ko, and Y. L. Xu. "Optimal Performance of the TLCD in Structural Pitching Vibration Control." Journal of Vibration and Control 8, no. 5 (May 2002): 619–42. http://dx.doi.org/10.1177/1077546029287.

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A detailed optimal parametric study is performed for a tuned liquid column damper (TLCD) in suppressing the pitching vibration of structures. Due to the difficulty of finding analytical solutions for the damped structure, a numerical optimization approach is proposed and applied to the system to find the optimum TLCD parameters. The variations of the optimum control parameter with system parameters are determined and discussed. Using various numerical searching data, a set of practical design formulas for the optimum tuning ratio and optimum head loss coefficient of the TLCD are then derived through regression analysis. The comparison between practical design formula and numerical optimization shows a very close agreement between the two results. The practical design formulas provide a convenient tool for designers. In order to account for the possible effects of structural uncertainties, a parametric sensitivity study on the de-tuning of optimum damper parameters is also carried out. It is found that the detuning effect is more severe for low damped structure with lower ratios of mass moment of inertia, especially for the detuning of tuning ratio.
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Ohsaki, M., and Tsuneyoshi Nakamura. "Optimum design with imperfection sensitivity coefficients for limit point loads." Structural Optimization 8, no. 2-3 (October 1994): 131–37. http://dx.doi.org/10.1007/bf01743310.

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Lowen, Philip D. "Parameter sensitivity in stochastic optimal control∗." Stochastics 22, no. 1 (September 1987): 1–40. http://dx.doi.org/10.1080/17442508708833465.

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Fonseca, Ijar M., and Peter M. Bainum. "Integrated Structural and Control Optimization." Journal of Vibration and Control 10, no. 10 (October 2004): 1377–91. http://dx.doi.org/10.1177/1077546304042043.

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This paper focuses on the integrated structural/control optimization of a large space structure with a robot arm subject to the gravity-gradient torque through a semi-analytical approach. It is well known that the computer effort to compute numerically derivatives of the constraints with respect to design variables makes the process expensive and time-consuming. In this sense, a semi-analytical approach may represent a good alternative when optimizing systems that require sensitivity calculations with respect to design parameters. In this study, constraints from the structure and control disciplines are imposed on the optimization process with the aim of obtaining the structure’s minimum weight and the optimum control performance. In the process optimization, the sensitivity of the constraints is computed by a semi-analytical approach. This approach combines the use of analytical derivatives of the mass and stiffness matrices with the numerical solution of the eigenvalue problem to obtain the eigenvalue derivative with respect to the design variables. The analytical derivatives are easy to obtain since our space structure is a long one-dimensional beam-like spacecraft.
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Kajiwara, I., and A. Nagamatsu. "Optimum Design of Optical Pick-Up by Elimination of Resonance Peaks." Journal of Vibration and Acoustics 115, no. 4 (October 1, 1993): 377–83. http://dx.doi.org/10.1115/1.2930360.

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A method for structural dynamic optimization is proposed using sensitivity analysis of resonance and anti-resonance frequencies. The sensitivity of the anti-resonance frequency is newly defined. An approach for eliminating the resonance peak from the frequency response function (FRF) is proposed using this sensitivity, modifying both the frequencies of this resonance and the neighboring anti-resonance bottom to the same value. The proposed method is applied to determine the optimum thickness of a plate in order to eliminate resonance peaks from its FRF. Effectiveness of this method is verified experimentally. Optimum design of an optical actuator for a compact disk player is performed practically by eliminating resonance peaks which deteriorates its servo control function. The player, with this optimized actuator, shows an excellent performance of sound playback.
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Moita, P. P., J. B. Cardoso, and A. J. Valido. "A Space-Time Finite Element Model for Design and Control Optimization of Nonlinear Dynamic Response." Shock and Vibration 15, no. 3-4 (2008): 307–14. http://dx.doi.org/10.1155/2008/721760.

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A design and control sensitivity analysis and multicriteria optimization formulation is derived for flexible mechanical systems. This formulation is implemented in an optimum design code and it is applied to the nonlinear dynamic response. By extending the spatial domain to the space-time domain and treating the design variables as control variables that do not change with time, the design space is included in the control space. Thus, one can unify in one single formulation the problems of optimum design and optimal control. Structural dimensions as well as lumped damping and stiffness parameters plus control driven forces, are considered as decision variables. The dynamic response and its sensitivity with respect to the design and control variables are discretized via space-time finite elements, and are integrated at-once, as it is traditionally used for static response. The adjoint system approach is used to determine the design sensitivities. Design optimization numerical examples are performed. Nonlinear programming and optimality criteria may be used for the optimization process. A normalized weighted bound formulation is used to handle multicriteria problems.
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Dissertations / Theses on the topic "Sensitivity of optimum control"

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Pfeiffer, Laurent. "Sensitivity analysis for optimal control problems. Stochastic optimal control with a probability constraint." Palaiseau, Ecole polytechnique, 2013. https://pastel.hal.science/docs/00/88/11/19/PDF/thesePfeiffer.pdf.

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Cette thèse est divisée en deux parties. Dans la première partie, nous étudions des problèmes de contrôle optimal déterministes avec contraintes et nous nous intéressons à des questions d'analyse de sensibilité. Le point de vue que nous adoptons est celui de l'optimisation abstraite; les conditions d'optimalité nécessaires et suffisantes du second ordre jouent alors un rôle crucial et sont également étudiées en tant que telles. Dans cette thèse, nous nous intéressons à des solutions fortes. De façon générale, nous employons ce terme générique pour désigner des contrôles localement optimaux pour la norme L1. En renforçant la notion d'optimalité locale utilisée, nous nous attendons à obtenir des résultats plus forts. Deux outils sont utilisés de façon essentielle : une technique de relaxation, qui consiste à utiliser plusieurs contrôles simultanément, ainsi qu'un principe de décomposition, qui est un développement de Taylor au second ordre particulier du lagrangien. Les chapitres 2 et 3 portent sur les conditions d'optimalité nécessaires et suffisantes du second ordre pour des solutions fortes de problèmes avec contraintes pures, mixtes et sur l'état final. Dans le chapitre 4, nous réalisons une analyse de sensibilité pour des problèmes relaxés avec des contraintes sur l'état final. Dans le chapitre 5, nous réalisons une analyse de sensibilité pour un problème de production d'énergie nucléaire. Dans la deuxième partie, nous étudions des problèmes de contrôle optimal stochastique sous contrainte en probabilité. Nous étudions une approche par programmation dynamique, dans laquelle le niveau de probabilité est vu comme une variable d'état supplémentaire. Dans ce cadre, nous montrons que la sensibilité de la fonction valeur par rapport au niveau de probabilité est constante le long des trajectoires optimales. Cette analyse nous permet de développer des méthodes numériques pour des problèmes en temps continu. Ces résultats sont présentés dans le chapitre 6, dans lequel nous étudions également une application à la gestion actif-passif
This thesis is divided into two parts. In the first part, we study constrained deterministic optimal control problems and sensitivity analysis issues, from the point of view of abstract optimization. Second-order necessary and sufficient optimality conditions, which play an important role in sensitivity analysis, are also investigated. In this thesis, we are interested in strong solutions. We use this generic term for locally optimal controls for the L1-norm, roughly speaking. We use two essential tools: a relaxation technique, which consists in using simultaneously several controls, and a decomposition principle, which is a particular second-order Taylor expansion of the Lagrangian. Chapters 2 and 3 deal with second-order necessary and sufficient optimality conditions for strong solutions of problems with pure, mixed, and final-state constraints. In Chapter 4, we perform a sensitivity analysis for strong solutions of relaxed problems with final-state constraints. In Chapter 5, we perform a sensitivity analysis for a problem of nuclear energy production. In the second part of the thesis, we study stochastic optimal control problems with a probability constraint. We study an approach by dynamic programming, in which the level of probability is a supplementary state variable. In this framework, we show that the sensitivity of the value function with respect to the probability level is constant along optimal trajectories. We use this analysis to design numerical schemes for continuous-time problems. These results are presented in Chapter 6, in which we also study an application to asset-liability management
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Wong, Man-kwun, and 黃文冠. "Some sensitivity results for time-delay optimal control problems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31223655.

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Scarinci, Teresa. "Sensitivity Relations and Regularity of Solutions of HJB Equations arising in Optimal Control." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066573.

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Dans cette thèse nous étudions une classe d’équations de Hamilton-Jacobi-Bellman provenant de la théorie du contrôle optimal des équations différentielles ordinaires. Nous nous intéressons principalement à l’analyse de la sensibilité de la fonction valeur des problèmes de contrôle optimal associés à de telles équations de H-J-B. Dans la littérature, les relations de sensibilité fournissent une “mesure” de la robustesse des stratégies optimales par rapport aux variations de la variable d’état. Ces résultats sont des outils très importants pour le contrôle appliqué, parce qu’ils permettent d’étudier les effets que des approximations des données du système peuvent avoir sur les politiques optimales. Cette thèse est dédiée également à l’étude des problèmes de Mayer et de temps minimal. Nous supposons que la dynamique du problème soit une inclusion différentielle, afin de permettre aux données d’être non régulières et d’embrasser un ensemble plus grand d’applications. Néanmoins, cette tâche rend notre analyse plus difficile. La première contribution de cette étude est une extension de quelques résultats classiques de la théorie de la sensibilité au domaine des problèmes non paramétrées. Ces relations prennent la forme d’inclusions d’état adjoint, figurant dans le principe du maximum de Pontryagin, dans certains gradients généralisés de la fonction valeur évalués le long des trajectoires optimales. En deuxième lieu, nous développons des nouvelles relations de sensibilité impliquant des approximations du deuxième ordre de la fonction valeur. Cette analyse mène à de nouvelles applications concernant la propagation, tant ponctuel que local, de la régularité de la fonction valeur le long des trajectoires optimales. Nous proposons également des applications aux conditions d’optimalité
This dissertation investigates a class of Hamilton-Jacobi-Bellman equations arising in optimal control of O.D.E.. We mainly focus on the sensitivity analysis of the optimal value function associated with the underlying control problems. In the literature, sensitivity relations provide a measure of the robustness of optimal control strategies with respect to variations of the state variable. This is a central tool in applied control, since it allows to study the effects that approximations of the inputs of the system may produce on the optimal policies. In this thesis, we deal whit problems in the Mayer or in the minimum time form. We assume that the dynamic is described by a differential inclusion, in order to allow data to be nonsmooth and to embrace a large area of concrete applications. Nevertheless, this task makes our analysis more challenging. Our main contribution is twofold. We first extend some classical results on sensitivity analysis to the field of nonparameterized problems. These relations take the form of inclusions of the co-state, featuring in the Pontryagin maximum principle, into suitable gradients of the value function evaluated along optimal trajectories. Furthermore, we develop new second-order sensitivity relations involving suitable second order approximations of the optimal value function. Besides being of intrinsic interest, this analysis leads to new consequences regarding the propagation of both pointwise and local regularity of the optimal value functions along optimal trajectories. As applications, we also provide refined necessary optimality conditions for some class of differential inclusions
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Hannemann-Tamás, Ralf [Verfasser]. "Adjoint Sensitivity Analysis for Optimal Control of Non-Smooth Differential-Algebraic Equations / Ralf Hannemann-Tamás." Aachen : Shaker, 2013. http://d-nb.info/1051575753/34.

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Park, Sungho. "Development and Applications of Finite Elements in Time Domain." Diss., Virginia Tech, 1996. http://hdl.handle.net/10919/30693.

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A bilinear formulation is used for developing the time finite element method (TFM) to obtain transient responses of both linear, nonlinear, damped and undamped systems. Also the formulation, used in the h-, p- and hp-versions, is extended and found to be readily amenable to multi-degree-of-freedom systems. The resulting linear and nonlinear algebraic equations for the transient response are differentiated to obtain the sensitivity of the response with respect to various design parameters. The present developments were tested on a series of linear and nonlinear examples and were found to yield, when compared with other methods, excellent results for both the transient response and its sensitivity to system parameters. Mostly, the results were obtained using the Legendre polynomials as basis functions, though, in some cases other orthogonal polynomials namely, Hermite, Chebyshev, and integrated Legendre polynomials were also employed (but to no great advantage). A key advantage of TFM, and the one often overlooked in its past applications, is the ease in which the sensitivity of the transient response with respect to various design parameters can be obtained. Since a considerable effort is spent in determining the sensitivity of the response with respect to system parameters in many algorithms for parametric identification, an identification procedure based on the TFM is developed and tested for a number of nonlinear single-and two-degree-of-freedom system problems. An advantage of the TFM is the easy calculation of the sensitivity of the transient response with respect to various design parameters, a key requirement for gradient-based parameter identification schemes. The method is simple, since one obtains the sensitivity of the response to system parameters by differentiating the algebraic equations, not original differential equations. These sensitivities are used in Levenberg-Marquardt iterative direct method to identify parameters for nonlinear single- and two-degree-of-freedom systems. The measured response was simulated by integrating the example nonlinear systems using the given values of the system parameters. To study the influence of the measurement noise on parameter identification, random noise is added to the simulated response. The accuracy and the efficiency of the present method is compared to a previously available approach that employs a multistep method to integrate nonlinear differential equations. It is seen, for the same accuracy, the present approach requires fewer data points. Finally, the TFM for optimal control problems based on Hamiltonian weak formulation is proposed by adopting the p- and hp-versions as a finite element discretization process. The p-version can be used to improve the accuracy of the solution by adding more unknowns to each element without refining the mesh. The usage of hierarchical type of shape functions can lead to a significant saving in computational effort for a given accuracy. A set of Legendre polynomials are chosen as higher order shape functions and applied to two simple minimization problems for optimal control. The proposed formulation provides very accurate results for these problems.
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Евсина, Наталья Александровна. "Синтез нечеткого регулятора для системы управления процессом сушки капиллярно-пористых материалов." Thesis, НТУ "ХПИ", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/19590.

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Диссертация на соискание ученой степени кандидата технических наук по специальности 05.13. 03 - системы и процессы управления. - Национальный технический университет "Харьковский политехнический институт", Харьков, 2015. Диссертация посвящена разработке и совершенствованию метода синтеза нечеткого регулятора, который обеспечивает заданное качество управления сушкой капиллярно-пористых материалов в конвекционной сушилке периодического действия и позволяет создавать системы управления, опирающиеся на экспертные знания. В диссертационной работе усовершенствован метод анализа чувствительности оптимального управления в линейной системе при квадратичном критерии качества, который позволил получить условия нечувствительности этого управления в замкнутой системе к малым изменениям параметров. Показано, что в общем случае необходимо совместное исследование чувствительности оптимизируемого функционала и чувствительности оптимальной траектории движения. Предложенный в работе алгоритм синтеза нечеткого логического регулятора позволяет использовать стандартную форму описания лингвистических переменных и минимальный набор управляющих правил. В работе выполнена оптимизация параметров и структуры нечетких регуляторов, что позволяет с небольшим количеством управляющих правил решать задачу выбора значений коэффициентов регулятора, который минимизирует критерий качества переходного процесса.
The thesis on Candidate Degree in Technical Sciences: Specialty 05.13. 03 - management systems and processes.– National Technical University "Kharkov Polytechnic Institute", Kharkov 2015. This thesis is devoted to the development and improvement of the synthesis method of a fuzzy regulator which ensures the specified quality to control the drying of the capillary and porous materials in a convection oven of periodic action and allows creating the control systems basing on the expert knowledge. The work describes the improved method of the optimal control sensitivity analysis in a linear system with a quadratic quality criterion which allowed obtaining the control insensitivity conditions to a slightly changed parameters in a closed system. Basing on the performed analysis the thesis shows the necessity to perform a joint research of the optimized functionality sensitivity and the sensitivity of the optimal movementtrajectory. The thesis offers a simple synthesis algorithm of the fuzzy and logical regulator which provides the ability to use a standard format describing the linguistic variables and a minimum set of the operating rules. The regulators built on the basis of fuzzy logic in some cases are capable to provide higher quality rates of the transition processes in comparison with classic regulators. Using the synthesis methods of fuzzy control algorithms, it is possible to optimize the difficult control loops omitting mathematical model specification.
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Ramirez, Ivan. "Mathematical Modeling of Immune Responses to Hepatitis C Virus Infection." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etd/2425.

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An existing mathematical model of ordinary differential equations was studied to better understand the interactions between hepatitis C virus (HCV) and the immune system cells in the human body. Three possible qualitative scenarios were explored: dominant CTL response, dominant antibody response, and coexistence. Additionally, a sensitivity analysis was carried out to rank model parameters for each of these scenarios. Therapy was addressed as an optimal control problem. Numerical solutions of optimal controls were computed using a forward-backward sweep scheme for each scenario. Model parameters were estimated using ordinary least squares fitting from longitudinal data (serum HCV RNA measurements) given in reported literature.
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Євсіна, Наталя Олександрівна. "Синтез нечіткого регулятора для системи управління процесом сушіння капілярно-пористих матеріалів." Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/19587.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.13. 03 – системи та процеси управління. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2015. Дисертацію присвячено розробці та вдосконаленню методу синтезу нечіткого регулятора, який забезпечує задану якість управління сушінням капілярно – пористих матеріалів в конвекційній сушарці періодичної дії та дозволяє створювати системи управління, що спираються на експертні знання. Удосконалено метод аналізу чутливості оптимального управління в лінійній системі при квадратичному критерії якості, який дозволив отримати умови нечутливості цього управління в замкнутій системі до малих змін параметрів. Показано, що в загальному випадку необхідно спільне дослідження чутливості функціонала, що оптимізується і чутливості оптимальної траєкторії руху. Запропоновано алгоритм синтезу нечітко-логічного регулятора, що дозволяє використовувати стандартну форму опису лінгвістичних змінних і мінімальний набір керуючих правил. Здійснено синтез нечітких регуляторів з оптимізацією їх параметрів і структури та запропоновано структурну схему нечіткого контролера. В роботі розроблені імітаційні моделі процесу сушіння КПМ, що описують зміну температури і вологості при природній та комбінованої циркуляції сушильного агенту в камерній сушарці періодичної дії, які використовуються для налаштування адаптивних нечітких регуляторів. Синтезований адаптивний нечіткий регулятор стабілізації температури сушильного агенту дозволяє в широкому діапазоні факторів, що збурюють, отримати мінімальний покращений критерій якості системи управління в порівнянні з класичним регулятором.
The thesis on Candidate Degree in Technical Sciences: Specialty 05.13. 03 - management systems and processes.– National Technical University "Kharkov Polytechnic Institute", Kharkov 2015. This thesis is devoted to the development and improvement of the synthesis method of a fuzzy regulator which ensures the specified quality to control the drying of the capillary and porous materials in a convection oven of periodic action and allows creating the control systems basing on the expert knowledge. The work describes the improved method of the optimal control sensitivity analysis in a linear system with a quadratic quality criterion which allowed obtaining the control insensitivity conditions to a slightly changed parameters in a closed system. Basing on the performed analysis the thesis shows the necessity to perform a joint research of the optimized functionality sensitivity and the sensitivity of the optimal movementtrajectory. The thesis offers a simple synthesis algorithm of the fuzzy and logical regulator which provides the ability to use a standard format describing the linguistic variables and a minimum set of the operating rules. The regulators built on the basis of fuzzy logic in some cases are capable to provide higher quality rates of the transition processes in comparison with classic regulators. Using the synthesis methods of fuzzy control algorithms, it is possible to optimize the difficult control loops omitting mathematical model specification.
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Rockenfeller, Robert [Verfasser], Thomas [Akademischer Betreuer] [Gutachter] Götz, and Jörg [Gutachter] Fehr. "On the application of mathematical methods in Hill-type muscle modeling: stability, sensitivity and optimal control / Robert Rockenfeller. Betreuer: Thomas Götz. Gutachter: Thomas Götz ; Jörg Fehr." Koblenz, 2016. http://d-nb.info/111089550X/34.

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Seelbinder, David [Verfasser], Christof [Akademischer Betreuer] [Gutachter] Büskens, and Stephan [Gutachter] Theil. "On-board Trajectory Computation for Mars Atmospheric Entry Based on Parametric Sensitivity Analysis of Optimal Control Problems / David Seelbinder ; Gutachter: Christof Büskens, Stephan Theil ; Betreuer: Christof Büskens." Bremen : Staats- und Universitätsbibliothek Bremen, 2017. http://d-nb.info/1141277700/34.

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Books on the topic "Sensitivity of optimum control"

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Choi, Kyung K. Shape design sensitivity analysis and optimal design of structural systems. [Washington, DC: National Aeronautics and Space Administration, 1987.

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Skelton, Robert E. Sensitivity, optimal scaling, and minimum roundoff errors in flexible structure models: Progress report. West Lafayette, Ind: Purdue University, School of Aeronautics and Astronautics, 1987.

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Halyo, Nesim. Investigation, development, and application of optimal output feedback theory: Volume IV : Measures of eigenvalue/eigenvector sensitivity to system parameters and unmodeled dynamics. Hampton, Va: Langley Research Center, 1987.

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Reed, D. W. Optimum control of pump operations. Wallingford: Institute of Hydrology, 1993.

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Midkhatovich, I͡U︡supov Rafaėlʹ, ed. Sensitivity of automatic control systems. Boca Raton, Fla: CRC Press, 2000.

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Gwendolyn, Johnson-Acsadi, IPPF Programme Committee., and World Fertility Survey, eds. Optimum conditions for childbearing. London: International Planned Parenthood Federation, 1986.

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NATO Advanced Research Workshop on Modelling, Robustness, and Sensitivity Reduction in Control Systems (1986 Groningen, Netherlands). Modelling, robustness, and sensitivity reduction in control systems. Berlin: Springer-Verlag, 1987.

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Curtain, Ruth F., ed. Modelling, Robustness and Sensitivity Reduction in Control Systems. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-87516-8.

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Lust, Robert. Control augmented structural synthesis. Hampton, Va: Langley Research Center, 1988.

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Robertson, A. Vector control of induction motors: Sensitivity to parameter variations. Manchester: UMIST, 1994.

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Book chapters on the topic "Sensitivity of optimum control"

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Weinmann, Alexander. "Optimal Control and Performance Sensitivity." In Uncertain Models and Robust Control, 123–36. Vienna: Springer Vienna, 1991. http://dx.doi.org/10.1007/978-3-7091-6711-3_9.

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García, David, Jorge Martínez, and Vicent Pla. "Admission Control Policies in Multiservice Cellular Networks: Optimum Configuration and Sensitivity." In Wireless Systems and Mobility in Next Generation Internet, 121–35. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/978-3-540-31963-4_9.

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Rentrop, Peter, Sven-Olaf Stoll, and Utz Weyer. "Sensitivity Calculations for 2D-Optimization of Turbomachine Blading." In Optimal Control of Complex Structures, 203–16. Basel: Birkhäuser Basel, 2001. http://dx.doi.org/10.1007/978-3-0348-8148-7_17.

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Szefer, G. "Sensitivity and Optimal Control in Contact Mechanics." In Multifield Problems, 219–28. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/978-3-662-04015-7_24.

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Caillau, Jean-Baptiste, and Joseph Noailles. "Continuous Optimal Control Sensitivity Analysis with AD." In Automatic Differentiation of Algorithms, 109–15. New York, NY: Springer New York, 2002. http://dx.doi.org/10.1007/978-1-4613-0075-5_11.

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Newman, Perry A. "Preparation of Advanced CFD Codes for use in Sensitivity Analyses and Multidisiplinary Design Optimization." In Optimal Design and Control, 241–74. Boston, MA: Birkhäuser Boston, 1995. http://dx.doi.org/10.1007/978-1-4612-0839-6_16.

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Young, N. J. "Super-optimal Hankel norm approximations." In Modelling, Robustness and Sensitivity Reduction in Control Systems, 47–56. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-87516-8_3.

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Kiehl, Martin. "Sensitivity Analysis of Stiff and Non-Stiff Initial-Value Problems." In Variational Calculus, Optimal Control and Applications, 143–52. Basel: Birkhäuser Basel, 1998. http://dx.doi.org/10.1007/978-3-0348-8802-8_15.

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Safonov, Michael G. "Imaginary-Axis Zeros in Multivariable H∞-Optimal Control." In Modelling, Robustness and Sensitivity Reduction in Control Systems, 71–81. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-87516-8_5.

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Zames, George, Allen Tannenbaum, and Cyprian Foias. "Optimal H ∞-Interpolation: A New Approach." In Modelling, Robustness and Sensitivity Reduction in Control Systems, 381–98. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-87516-8_22.

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Conference papers on the topic "Sensitivity of optimum control"

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Yu, C. W. "Sensitivity analysis of multi-area optimum power flow solutions." In 3rd International Conference on Advances in Power System Control, Operation and Management (APSCOM 95). IEE, 1995. http://dx.doi.org/10.1049/cp:19951281.

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Araujo, Antonio, Simone Gallani, Michela Mulas, and Sigurd Skogestad. "Sensitivity of optimal operation of an activated sludge process model." In 2012 UKACC International Conference on Control (CONTROL). IEEE, 2012. http://dx.doi.org/10.1109/control.2012.6334639.

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Erdal, C. "A sensitivity measure for an electronic, Proportional-Integral (PI) controller and calculating optimum parameter tolerances." In UKACC International Conference on Control (CONTROL '98). IEE, 1998. http://dx.doi.org/10.1049/cp:19980240.

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Kajiwara, I., and A. Nagamatsu. "An Approach to Simultaneous Optimum Design of Structure and Control Systems by Sensitivity Analysis." In ASME 1991 Design Technical Conferences. American Society of Mechanical Engineers, 1991. http://dx.doi.org/10.1115/detc1991-0382.

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Abstract An approach is proposed for simultaneous optimum design of a structure and feedback control system by sensitivity analysis for the following two purposes. One is to decrease both the response and the control force of the system under a white noise disturbance force. The other is to modify the gain, the pole and the zero-point to the desirable values. The weighting constant of the feedback control system, and mass, stiffness, shape, dimension, etc. of the structure are adopted simultaneously as the design variables. The proposed method is verified by a model simulation.
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Qin, Wei, Zhuang Kang, and Youwei Kang. "Free Standing Hybrid Riser Global Parametric Sensitivity Analysis and Optimum Design." In ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49606.

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With a rigid pipe for the vertical free standing portion and a flexible pipe for the near surface dynamic motion region, Free Standing Hybrid Riser (FSHR) has been widely accepted within the offshore oil and gas industry, especially in the field of West of Africa, Gulf of Mexico and field of Brazil. So the optimum design of FSHR system is becoming increasingly meaningful and necessary. This paper mainly presents the parametric sensitivity analysis and optimization of deepwater Free Standing Hybrid Riser (FSHR). First of all, a general description about FSHR system is given in the introduction. The components of FSHR and their function are presented in detail. Secondly, the procedure for parameters optimum design is discussed, and in order to make it looks more clearly and directly, a flowchart is illustrated to show the process. Considering the design requirements for a deepwater FSHR, the optimum design mathematic model is presented with the optimal objective - minimum of FSHR total weight which is directly proportional to project cost. Thirdly, a design instance is given to make clear the flow of FSHR optimum design with the best performance. The global strength analysis is carried out with the use of generic FEA tools. Then the parametric sensitivity analysis is performed through Single-Variable Control Method. Based on FSHR global strength analysis, four sensitivity parameters are carried out, and the minimum bending radius (MBR) of Flexible Jumper and the max von Misses stress are checked according to API RP 2RD. The relationship between sensitivity parameters and the response of the riser system is briefly discussed and the regress analysis can be used to quantify the relativity. Finally, the parameters optimum design is analyzed and the optimum results are checked to ensure its validity.
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Kajiwara, I., K. Tsujioka, and A. Nagamatsu. "Integrated Optimum Design of Structure and Control System by Modal Analysis." In ASME 1995 Design Engineering Technical Conferences collocated with the ASME 1995 15th International Computers in Engineering Conference and the ASME 1995 9th Annual Engineering Database Symposium. American Society of Mechanical Engineers, 1995. http://dx.doi.org/10.1115/detc1995-0608.

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Abstract An approach for integrated optimum design of structure and control system is presented based on modal analysis. This approach consists of two process, namely the process by sensitivity analysis using optimal regulator theory and the process by the complex method in which a control system is composed of a small-order output feedback. In both processes, the design variables of the structural and the control parameters are optimized simultaneously in order to minimize the response due to disturbances of both white noise and colored noise. The integrated optimum design is performed by minimizing the objective function with respect to the response under the constraints of the control cost and the stability of the closed-loop system corresponding to high order natural modes. The validity and the usefulness of the present approach are verified by a vibration control experiment with a steel plate.
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Shikoska, U., D. Davchev, J. Shikoski, Nader Barsoum, Sermsak Uatrongjit, and Pandian Vasant. "THE THEORETICAL FOUNDATION OF SENSITIVITY ANALYSIS FOR GPS." In INTERNATIONAL CONFERENCE ON POWER CONTROL AND OPTIMIZATION: Innovation in Power Control for Optimal Industry. AIP, 2008. http://dx.doi.org/10.1063/1.3008685.

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Bani Younes, Ahmad, and James Turner. "Feedback Control Sensitivity Calculations Using Computational Differentiation." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-51439.

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Feedback control is a powerful methodology for handling model and parameter uncertainty in real-world applications. Given a useful nominal plant model for developing the control approach, it is well-known that optimal solutions only perform well for a limited range of model and parameter uncertainty. A higher-order optimal nonlinear feedback control strategy is presented where the feedback control is augmented with feedback gain sensitivity partial derivatives for handling model uncertainties. The computational differentiation (CD) toolbox is used for automatically generating higher-order partial derivatives for the feedback gain differential equations. An estimator is assumed to be available for predicting the model parameter changes. The optimal gain is computed as a Taylor series expansion in the gains, where the feedback gains are expanded as a function of the system model parameters. Derivative enhanced optimal feedback control is shown to be robust to large changes in the model parameters. Numerical examples are presented that demonstrate the effectiveness of the proposed methodology.
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Zhou, Jian, and Rajab Challoo. "Low-Sensitivity Optimal Control with Prescribed Closed-loop Eigenvalues." In 1992 American Control Conference. IEEE, 1992. http://dx.doi.org/10.23919/acc.1992.4792158.

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Kanno, Masaaki, Shinji Hara, Ryosuke Nakamura, and Mitsuru Matsubara. "Algebraic approach to sensitivity analysis in optimal feedback control system design." In Control (MSC). IEEE, 2010. http://dx.doi.org/10.1109/cacsd.2010.5612659.

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Reports on the topic "Sensitivity of optimum control"

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Falco, R. E. Sensitivity to Turbulent Boundary Layer Production Mechanisms to Turbulence Control. Fort Belvoir, VA: Defense Technical Information Center, March 1991. http://dx.doi.org/10.21236/ada250210.

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Suzuki, Kunihiko, Taizou Miyazaki, Mamoru Nemoto, and Kenichi Machida. Optimum Control of Spark Ignition Timing in a Gasoline Engine Using Model-Based Methodology. Warrendale, PA: SAE International, September 2005. http://dx.doi.org/10.4271/2005-08-0512.

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Serakos, Demetrios. PHALANX CIWS Control System Stability, Aim Bias Compensation, and Noise- Sensitivity. Fort Belvoir, VA: Defense Technical Information Center, May 1992. http://dx.doi.org/10.21236/ada264733.

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Young, Yan. A Preliminary Study of Sensitivity Analysis and its Applications to Structural Control Problems. Fort Belvoir, VA: Defense Technical Information Center, January 1991. http://dx.doi.org/10.21236/ada363042.

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Barakat, David J., Samuel R. Denmeade, and Alan D. Friedman. Regulating Prostate Cancer Sensitivity to Chemotherapy through Translational Control of CCAAT Enhancer Binding Proteins. Fort Belvoir, VA: Defense Technical Information Center, August 2015. http://dx.doi.org/10.21236/ada621015.

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Regalbuto, M. C., B. Misra, D. B. Chamberlain, R. A. Leonard, and G. F. Vandegrift. The monitoring and control of TRUEX processes. Volume 1, The use of sensitivity analysis to determine key process variables and their control bounds. Office of Scientific and Technical Information (OSTI), April 1992. http://dx.doi.org/10.2172/10177602.

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Firon, Nurit, Prem Chourey, Etan Pressman, Allen Hartwell, and Kenneth J. Boote. Molecular Identification and Characterization of Heat-Stress-Responsive Microgametogenesis Genes in Tomato and Sorghum - A Feasibility Study. United States Department of Agriculture, October 2007. http://dx.doi.org/10.32747/2007.7591741.bard.

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Exposure to higher than optimal temperatures - heat-stress (HS) - is becoming increasingly common to all crop plants worldwide. Heat stress coinciding with microgametogenesis, especially during the post-meiotic phase that is marked by starch biosynthesis, is often associated with starch-deficient pollen and male sterility and ultimately, greatly reduced crop yields. The molecular basis for the high sensitivity of developing pollen grains, on one hand, and factors involved in pollen heat-tolerance, on the other, is poorly understood. The long-term goal of this project is to provide a better understanding of the genes that control pollen quality under heat-stress conditions. The specific objectives of this project were: (1) Determination of the threshold heat stress temperature(s) that affects tomato and sorghum pollen quality whether: a) Chronic mild heat stress conditions (CMHS), or b) Acute heat stress (AHS). (2) Isolation of heat-responsive, microgametogenesis-specific sequences. During our one-year feasibility project, we have accomplished the proposed objectives as follows: Objectrive 1: We have determined the threshold HS conditions in tomato and sorghum. This was essential for achieving the 2nd objective, since our accumulated experience (both Israeli and US labs) indicate that when temperature is raised too high above "threshold HS levels" it may cause massive death of the developing pollen grains. Above-threshold conditions have additional major disadvantages including the "noise" caused by induced expression of genes involved in cell death and masking of the differences between heatsensitive and heat-tolerant pollen grains. Two different types of HS conditions were determined: a) Season-long CMHS conditions: 32/26°C day/night temperatures confirmed in tomato and 36/26°C day maximum/night minimum temperatures in sorghum. b) Short-term AHS: In tomato, 2 hour exposure to 42-45°C (at 7 to 3 days before anthesis) followed by transfer to 28/22±2oC day/night temperatures until flower opening and pollen maturation, caused 50% reduced germinating pollen in the heat-sensitive 3017 cv.. In sorghum, 36/26°C day/night temperatures 10 to 5 days prior to panicle emergence, occurring at 35 days after sowing (DAS) in cv. DeKalb28E, produced starch-deficient and sterile pollen. Objective 2: We have established protocols for the high throughput transcriptomic approach, cDNA-AFLP, for identifying and isolating genes exhibiting differential expression in developing microspores exposed to either ambient or HS conditions and created a databank of HS-responsivemicrogametogenesis-expressed genes. A subset of differentially displayed Transcript-Derived Fragments (TDFs) that were cloned and sequenced (35 & 23 TDFs in tomato and sorghum, respectively) show close sequence similarities with metabolic genes, genes involved in regulation of carbohydrate metabolism, genes implicated in thermotolerance (heat shock proteins), genes involved in long chain fatty acids elongation, genes involved in proteolysis, in oxidation-reduction, vesicle-mediated transport, cell division and transcription factors. T-DNA-tagged Arabidopsis mutants for part of these genes were obtained to be used for their functional analysis. These studies are planned for a continuation project. Following functional analyses of these genes under HS – a valuable resource of genes, engaged in the HS-response of developing pollen grains, that could be modulated for the improvement of pollen quality under HS in both dicots and monocots and/or used to look for natural variability of such genes for selecting heat-tolerant germplasm - is expected.
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Lee, Jusang, John E. Haddock, Dario D. Batioja Alvarez, and Reyhaneh Rahbar Rastegar. Quality Control and Quality Assurance of Asphalt Mixtures Using Laboratory Rutting and Cracking Tests. Purdue University, 2019. http://dx.doi.org/10.5703/1288284317087.

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The main objectives of this project were to review the available balanced-mix design (BMD) methodologies, understand the I-FIT and Hamburg Wheel Tracking Test (HWTT) test methods using INDOT asphalt mixtures, and to explore the application of these tests to both a BMD approach and as performance-related Quality Control (QC) and Quality Acceptance (QA) methods. Two QA mixture specimen types, plant-mixed laboratory-compacted (PMLC) and plant-mixed field-compacted (PMFC) were used in the determination of cracking and rutting parameters. Distribution functions for the flexibility index (FI) values and rutting parameters were determined for various mixture types. The effects of specimen geometry and air voids contents on the calculated Flexibility Index (FI) and rutting parameters were investigated. The fatigue characteristics of selected asphalt mixtures were determined using the S-VECD test according to different FI levels for different conditions. A typical full-depth pavement section was implemented in FlexPAVE to explore the cracking characteristics of INDOT asphalt mixtures by investigating the relationship between the FI values of QA samples with the FlexPAVE pavement performance predictions. The FI values obtained from PMFC specimens were consistently higher than their corresponding PMLC specimens. This study also found that FI values were affected significantly by variations in specimen thickness and air voids contents, having higher FI values with higher air voids contents and thinner specimens. These observations do not agree with the general material-performance expectations that better cracking resistance is achieved with lower air voids content and thicker layers. Additionally, PG 70-22 mixtures show the lowest mean FI values followed by the PG 76-22 and 64-22 mixtures. The same order was observed from the ΔTc (asphalt binder cracking index) of INDOT’s 2017 and 2018 projects. Finally, it was found that the HWTT showed reasonable sensitivity to the different characteristics (e.g., aggregate sizes, binder types, and air voids contents) of asphalt mixtures. Mixtures containing modified asphalt binders showed better rut resistance and higher Rutting Resistance Index (RRI) than those containing unmodified binders.
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Hedrick, Ronald, and Herve Bercovier. Characterization and Control of KHV, A New Herpes Viral Pathogen of Koi and Common Carp. United States Department of Agriculture, January 2004. http://dx.doi.org/10.32747/2004.7695871.bard.

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In this project we proposed to characterize the virus genome and the structural virion polypeptides to allow development of improved diagnostic approaches and potential vaccination strategies. These goals have been mostly achieved and the corresponding data were published in three papers (see below) and three more manuscripts are in preparation. The virion polypeptides of KHV strains isolated from USA (KHV-U) and Israel (KHV-I) were found to be identical. Purified viral DNA analyzed with a total of 5 restriction enzymes demonstrated no fragment length polymorphism between KHV-I and KHV-U but both KHV isolates differed significantly from the cyprinid herpesvirus (CHV) and the ictalurid herpesvirus (channel catfish virus or CCV). Using newly obtained viral DNA sequences two different PCR assays were developed that need to be now further tested in the field. We determined by pulse field analysis that the size of KHV genome is around 280 kbp (1-1. Bercovier, unpublished results). Sequencing of the viral genome of KHV has reached the stage where 180 kbp are sequenced (twice and both strands). Four hypothetical genes were detected when DNA sequences were translated into amino acid sequences. The finding of a gene of real importance, the thymidine kinase (TK) led us to extend the study of this specific gene. Four other genes related to DNA synthesis were found. PCR assays based on defined sequences were developed. The PCR assay based on TK gene sequence has shown improved sensitivity in the detection of KHV DNA compared to regular PCR assays. </P> <P><SPAN>With the ability to induce experimental infections in koi with KHV under controlled laboratory conditions we have studied the progress and distribution of virus in host tissues, the development of immunity and the establishment of latent infections. Also, we have investigated the important role of water temperature on severity of infections and mortality of koi following infections with KHV. These initial studies need to be followed by an increased focus on long-term fate of the virus in survivors. This is essential in light of the current &quot;controlled exposure program&quot; used by farmers to produce KHV &quot;naturally resistant fish&quot; that may result in virus or DNA carriers. </SPAN></P> <P><SPAN>The information gained from the research of this project was designed to allow implementation of control measures to prevent the spread of the virus both by improved diagnostic approaches and preventive measures. We have accomplished most of these goals but further studies are needed to establish even more reliable methods of prevention with increased emphases on improved diagnosis and a better understanding of the ecology of KHV. </SPAN>
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Altstein, Miriam, and Ronald J. Nachman. Rational Design of Insect Control Agent Prototypes Based on Pyrokinin/PBAN Neuropeptide Antagonists. United States Department of Agriculture, August 2013. http://dx.doi.org/10.32747/2013.7593398.bard.

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The general objective of this study was to develop rationally designed mimetic antagonists (and agonists) of the PK/PBAN Np class with enhanced bio-stability and bioavailability as prototypes for effective and environmentally friendly pest insect management agents. The PK/PBAN family is a multifunctional group of Nps that mediates key functions in insects (sex pheromone biosynthesis, cuticular melanization, myotropic activity, diapause and pupal development) and is, therefore, of high scientific and applied interest. The objectives of the current study were: (i) to identify an antagonist biophores (ii) to develop an arsenal of amphiphilic topically active PK/PBAN antagonists with an array of different time-release profiles based on the previously developed prototype analog; (iii) to develop rationally designed non-peptide SMLs based on the antagonist biophore determined in (i) and evaluate them in cloned receptor microplate binding assays and by pheromonotropic, melanotropic and pupariation in vivo assays. (iv) to clone PK/PBAN receptors (PK/PBAN-Rs) for further understanding of receptor-ligand interactions; (v) to develop microplate binding assays for screening the above SMLs. In the course of the granting period A series of amphiphilic PK/PBAN analogs based on a linear lead antagonist from the previous BARD grant was synthesized that incorporated a diverse array of hydrophobic groups (HR-Suc-A[dF]PRLa). Others were synthesized via the attachment of polyethylene glycol (PEG) polymers. A hydrophobic, biostablePK/PBAN/DH analog DH-2Abf-K prevented the onset of the protective state of diapause in H. zea pupae [EC50=7 pmol/larva] following injection into the preceding larval stage. It effectively induces the crop pest to commit a form of ‘ecological suicide’. Evaluation of a set of amphiphilic PK analogs with a diverse array of hydrophobic groups of the formula HR-Suc-FTPRLa led to the identification of analog T-63 (HR=Decyl) that increased the extent of diapause termination by a factor of 70% when applied topically to newly emerged pupae. Another biostablePK analog PK-Oic-1 featured anti-feedant and aphicidal properties that matched the potency of some commercial aphicides. Native PK showed no significant activity. The aphicidal effects were blocked by a new PEGylated PK antagonist analog PK-dF-PEG4, suggesting that the activity is mediated by a PK/PBAN receptor and therefore indicative of a novel and selective mode-of-action. Using a novel transPro mimetic motif (dihydroimidazole; ‘Jones’) developed in previous BARD-sponsored work, the first antagonist for the diapause hormone (DH), DH-Jo, was developed and shown to block over 50% of H. zea pupal diapause termination activity of native DH. This novel antagonist development strategy may be applicable to other invertebrate and vertebrate hormones that feature a transPro in the active core. The research identifies a critical component of the antagonist biophore for this PK/PBAN receptor subtype, i.e. a trans-oriented Pro. Additional work led to the molecular cloning and functional characterization of the DH receptor from H. zea, allowing for the discovery of three other DH antagonist analogs: Drosophila ETH, a β-AA analog, and a dF analog. The receptor experiments identified an agonist (DH-2Abf-dA) with a maximal response greater than native DH. ‘Deconvolution’ of a rationally-designed nonpeptide heterocyclic combinatorial library with a cyclic bis-guanidino (BG) scaffold led to discovery of several members that elicited activity in a pupariation acceleration assay, and one that also showed activity in an H. zea diapause termination assay, eliciting a maximal response of 90%. Molecular cloning and functional characterization of a CAP2b antidiuretic receptor from the kissing bug (R. prolixus) as well as the first CAP2b and PK receptors from a tick was also achieved. Notably, the PK/PBAN-like receptor from the cattle fever tick is unique among known PK/PBAN and CAP2b receptors in that it can interact with both ligand types, providing further evidence for an evolutionary relationship between these two NP families. In the course of the granting period we also managed to clone the PK/PBAN-R of H. peltigera, to express it and the S. littoralis-R Sf-9 cells and to evaluate their interaction with a variety of PK/PBAN ligands. In addition, three functional microplate assays in a HTS format have been developed: a cell-membrane competitive ligand binding assay; a Ca flux assay and a whole cell cAMP ELISA. The Ca flux assay has been used for receptor characterization due to its extremely high sensitivity. Computer homology studies were carried out to predict both receptor’s SAR and based on this analysis 8 mutants have been generated. The bioavailability of small linear antagonistic peptides has been evaluated and was found to be highly effective as sex pheromone biosynthesis inhibitors. The activity of 11 new amphiphilic analogs has also been evaluated. Unfortunately, due to a problem with the Heliothis moth colony we were unable to select those with pheromonotropic antagonistic activity and further check their bioavailability. Six peptides exhibited some melanotropic antagonistic activity but due to the low inhibitory effect the peptides were not further tested for bioavailability in S. littoralis larvae. Despite the fact that no new antagonistic peptides were discovered in the course of this granting period the results contribute to a better understanding of the interaction of the PK/PBAN family of Nps with their receptors, provided several HT assays for screening of libraries of various origin for presence of PK/PBAN-Ragonists and antagonists and provided important practical information for the further design of new, peptide-based insecticide prototypes aimed at the disruption of key neuroendocrine physiological functions in pest insects.
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