An iterative algorithm is presented to compute lower bounds for the structured singular value ( mu ). The algorithm resembles a mixture of power methods for eigenvalues and singular values, since the structured singul...
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An iterative algorithm is presented to compute lower bounds for the structured singular value ( mu ). The algorithm resembles a mixture of power methods for eigenvalues and singular values, since the structured singular value can be viewed as a generalization of both. If the algorithm converges, a lower bound for mu results. The authors prove that mu is always an equilibrium point of the algorithm. However, since in general there are many equilibrium points, some heuristic ideas to achieve convergence are presented. Extensive numerical experience with the algorithm is discussed.< >
An on-line scheme to fault detection in adaptive controlsystems is proposed by introducing Kullbaek Discrimination Information (KDI) as a detection index. When a physical parameter change due to a failure has occurre...
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An on-line scheme to fault detection in adaptive controlsystems is proposed by introducing Kullbaek Discrimination Information (KDI) as a detection index. When a physical parameter change due to a failure has occurred in a system under adaptive control, the failure effect will hardly be visible in the output performance because of the adaptation mechanism. Such a parameter change is also difficult to detect by monitoring the regulator parameters, which are determined by a recursive identification based on the direct approach. Since the failure effect is reflected as a change in the predictor model used for the adaptive control design, the fault detection leads to a model discrimination problem. It has been shown that the KDI can be used as an effective distortion measure for the model discrimination and the index can be applied in a modified form to detect a fault on-line. Simulation studies on a second order damped oscillatory system have been carried out to demonstrate the efficiency of the method.
This paper presents general frequency domain criteria for the robust stability of systems with parametric uncertainities. The criteria are applied to the robust stability verification of LTI systems with or without ti...
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This paper presents general frequency domain criteria for the robust stability of systems with parametric uncertainities. The criteria are applied to the robust stability verification of LTI systems with or without time delays and of LTI systems operating under possibly nonlinear passive feedback.
The estimation of sinusoidal frequencies by the overdetermined Yule-Walker (OYW) Method is considered. An explicit expression is derived for the asymptotic covariance matrix of the estimation errors. The effect of inc...
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The estimation of sinusoidal frequencies by the overdetermined Yule-Walker (OYW) Method is considered. An explicit expression is derived for the asymptotic covariance matrix of the estimation errors. The effect of increasing the number of Yule-Walker equations on estimation accuracy is analyzed. The asymptotic estimation accuracy of the OYW method is compared to the best achievable accuracy corresponding to the Cramér-Rao bound
作者:
BLACKWELL, LMLuther M. Blackwell:is presently the Data Multiplex System (DMS) program manager in the Bridge Control
Monitoring and Information Transfer Branch of the Naval Sea Systems Command (NavSea). He graduated from the University of Maryland in 1964 receiving his BS degree in electrical engineering. After graduating he was employed in the Bureau of Ships where he held project engineering assignments on various ships entertainment magnetic tape recording fiber optics computer mass memory and information transfer systems. He has also pursued graduate studies in engineering management at The George Washington University.
The Data Multiplex System (DMS) is a general-purpose information transfer system directed toward fulfilling the internal data intercommunication requirements of a variety of naval combatant ships and submarines in the...
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The Data Multiplex System (DMS) is a general-purpose information transfer system directed toward fulfilling the internal data intercommunication requirements of a variety of naval combatant ships and submarines in the 1990–2000 time frame. The need for a modern data transfer system of the size and capability of DMS has increased as various digital controlsystems throughout naval ships have adopted distributed processing architectures and reconfigurable control consoles, and as the quantity of remotely sensed and controlled equipment throughout the ship has increased manyfold over what it was in past designs. Instead of miles of unique cabling that must be specifically designed for each ship, DMS will meet information transfer needs with general-purpose multiplex cable that will be installed according to a standard plan that does not vary with changes to the ship's electronics suite. Perhaps the greatest impact of DMS will be the decoupling of ship subsystems from each other and from the ship. Standard multiplex interfaces will avoid the cost and delay of modifying subsystems to make them compatible. The ability to wire a new ship according to a standard multiplex cable plan, long before the ship subsystems are fully defined, will free both the ship and the subsystems to develop at their own pace, will allow compression of the development schedules, and will provide ships with more advanced subsystems. This paper describes the DMS system as it is currently being introduced into the fleet by the U.S. Navy. The results of its design and implementation in the DDG-51 and LHD-1 class ships are also presented.
作者:
SWENSON, ENMAHINSKE, EBSTOUTENBURGH, JSCapt. Erick N. Swenson
USNR (Ret.):is a project manager for special projects in the Surface Ship Systems Division Hughes Aircraft Company Fullerton Calif where he has been employed since his retirement from the U.S. Navy in 1975. Originally trained as an electronics technician during WWII in the Captain Eddy program he later received a BS degree in electrical engineering from the University of Rochester Rochester N. Y. in 1950. Subsequent engineering education was received at the University of Pittsburgh Pittsburgh Penn. and the Naval Postgraduate School Monterey Calif. After commissioning he was ordered to duty as the electronics division officer on the USSMissouri(BB-63) and electronics ships superintendent at Hunters Point Naval Shipyard San Francisco Calif. When the design of the Naval Tactical Data System began in the mid-1950s Lt. (j.g.) Swenson was ordered to the Bureau of Ships Navy Department Washington D.C. as the junior engineering duty only officer assigned to the project. From 1962 to 1965 LCdr. Swenson was assigned as the BuShips technical representative on the program at Remington Rand Univac St. Paul Minn. For the next ten years he returned to BuShips/NavSea/NAVSEC as the NTDS project officer. During this time the project expanded considerably foreign military sales were heavily involved and interoperability with other services and countries were established. His final effort on active duty was to instigate the redesign of the previousSpruanceclass destroyers into the newerAdmiral Kiddclass improvement program. He is a registered professional electrical engineer in the State of California listed inWho's Who in the Worldis a life member of ASNE and chairman of the Long Beach/Greater LA Section. Capt. Edmund B. Mahinske
USN (Ret.):is an alumnus of the U.S. Naval Academy the Massachusetts Institute of Technology and the Harvard Business School. His technical background is in electronics and he specialized in the management of programs involving the application of comp
A little over thirty years ago, a group of naval engineers were assembled by the Bureau of Ships to develop a new system approach to the combat information center (CIC). The CIC of World War II, with its “grease pen...
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A little over thirty years ago, a group of naval engineers were assembled by the Bureau of Ships to develop a new system approach to the combat information center (CIC). The CIC of World War II, with its “grease pencil” plots and voice telling of tactical information from sensors and other ships, could no longer provide the timely, coordinated reaction to postwar threats. This project group led the Navy into the new world of large-scale, high-speed digital electronics and into a new mode of conducting naval warfare as well. There were no off-the-shelf computers of the requisite capability, size and reliability; what were available were monstrous vacuum tube computers. There were no display equipments that were “conversant” in both the digital language of the computer and the analog language of the sensors and the weapon systems. Who ever heard, at that time, of a computer running a tactical communication net automatically? It was hard enough to find sufficient numbers of engineers who knew what a digital computer was. This paper, by three naval engineers in the implementing engineering office, depicts the evolvement of the Naval Tactical Data systems (NTDS) as they saw it. It discusses the problems that stemmed from the transition from the old world of analog into the new digital world, the system concepts that steered the development; the key decisions that were made; new electronic equipment and processes that became necessary; and the need of the mangagement to face the real world of deadlines, ship schedules and operational requirements.
A new, flexible, mixed-integer formulation is presented for solving the single-stage AC-transmission expansion planning problem. This new formulation handles the discrete nature of equipment additions without resortin...
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A new, flexible, mixed-integer formulation is presented for solving the single-stage AC-transmission expansion planning problem. This new formulation handles the discrete nature of equipment additions without resorting to linearized incremental approaches, but still uses integer linear programming. Even the interconnection of an initially disjoint system is handled directly without resorting to an arbitrary initially connected system. The optimal configuration at the end of the planning step under consideration minimizes an annually amortized cost function including the investment cost for equipment additions and the operating cost in terms of real-power transmission losses. Using a new, efficient, linear load-flow model, the formulation developed here is characterized by a complete decoupling between real and reactive equations. Examples have been incorporated to illustrate the potentials of this new optimum planning formulation. A major contribution of this paper is in showing how the power system transmission expansion planning problem can fit into the standard, mixed-integer, linear programming format in both a conventional sensitivity formulation and also with our new implicit enumeration formulation.
This paper addresses some fundamental concerns pertaining to the subject of practical controller design for LTI plants with possibly distributed parameters. The well-posedness of a general LTI model is introduced in t...
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This paper addresses some fundamental concerns pertaining to the subject of practical controller design for LTI plants with possibly distributed parameters. The well-posedness of a general LTI model is introduced in terms of the existence of bandlimited stabilizing compensation for the given model. The well posedness of a model is critical from an implementation standpoint for the application of any model-based controller design methodology. The problem addressed in this paper is to characterize LTI distributed parameter models that are well posed with respect to bandlimited stabilising control. The problem is posed on a framework consisting of a novel class of convolution kernels and a completely general control system configuration. These two aspects of the problem formulation place no a priori restriction on the class of LTI distributed paramater systems under consideration or the control design methodology used. Indeed, this framework allows the modelling of LTI distributed parameter systems including point sensing, boundary actuation and effects of initial conditions. Within this framework the result obtained are algebraic in nature. A characterization of well-posed models is given in the form of necessary conditions for the existence of a bandlimited stabilizing controller. Also a restriction of the class of all linear distributed parameter systems under consideration is derived which exhibits this condition.
Two proposed programming standards for industrial automation, GRAFCET and SFC, are presented. The idea of what makes a `good' programming language is discussed, and the concept of a graphic programming language is...
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Two proposed programming standards for industrial automation, GRAFCET and SFC, are presented. The idea of what makes a `good' programming language is discussed, and the concept of a graphic programming language is introduced. The advantages and limitations of GRAFCET and SFC are presented. This paper concludes with a discussion of the need for further research for more general graphic programming languages for industrial automation.
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