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11th International Conference on Architectural Support for Programming Languages and Operating Systems

作者： Li, XD Li, ZM David, F Zhou, P Zhou, YY Adve, S Kumar, S Univ Illinois Dept Comp Sci Urbana IL 61801 USA Intel Labs Santa Clara CA USA

ISBN: (纸本)1581138040

Much research has been conducted on energy management for memory and disks. Most studies use control algorithms that dynamically transition devices to low power modes after they are idle for a certain threshold period of time. The control algorithms used in the past have two major limitations. First, they require painstaking, application-dependent manual tuning of their thresholds to achieve energy savings without significantly degrading performance. Second, they do not provide performance guarantees. In one case, they slowed down an application by 835%! This paper addresses these two limitations for both memory and disks, making memory/disk energy-saving schemes practical enough to use in real systems. Specifically, we make three contributions: (1) We propose a technique that provides a performance guarantee for control algorithms. We show that our method works well for all tested cases, even with previously proposed algorithms that are not performance-aware. (2) We propose a new control algorithm, Performance-directed Dynamic (PD), that dynamically adjusts its thresholds periodically, based on available slack and recent workload characteristics. For memory, PD consumes the least energy, when compared to previous hand-tuned algorithms combined with a performance guarantee. However, for disks, PD is too complex and its self-tuning is unable to beat previous hand-tuned algorithms. (3) To improve on PD, we propose a simple, optimization-based, threshold-free control algorithm, Performance-directed Static (PS). PS periodically assigns a static configuration by solving an optimization problem that incorporates information about the available slack and recent traffic variability to different chips/disks. We find that PS is the best or close to the best across all performance-guaranteed disk algorithms, including hand-tuned versions.

关键词： memory and disk energy management low power design adaptation algorithms control algorithms multiple power mode device

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Fiber-optical system for visualization of inner pipe defects by microrobot.

Fiber-optical system for visualization of inner pipe defects...

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Conference on Current Developments in Lens Design and Optical Engineering V

作者： Gradetsky, V Krabchuk, L Kniazkov, M Solovtsov, V Tulaikova, T Simakova, M Russian Acad Sci Inst Prob Mech Moscow 119526 Russia

ISBN: (纸本)0819454613

The control systems of the miniature robots are suggested for their motion over internal surfaces inside of the small diameter tubes. The mechanical system information-measuring sensor and control systems are considered. Three versions of the mechanical systems are suggested: electromagnetic, triad wheels and conversion of rotation motion to translation one. The electromagnetic mechanism use push pull tipe method for translation motion realization. Developed schemes in the modules design of control systems were checked experimentally on the robot's prototypes. Some results of the computer simulation illustrate the multilink robot control motion along the internal diameters of the tubes. This work was fulfilled under financial support of the Russian Found of Fundamental researches N 01-01-00913 and in frames of Federal Multi Purpose Scientific and Technical Program of Ministry of Industry, Science and Technologies: "Researches and Developments on priority directions of science and technology", "Knowledgeable basic investigations" block, "Basic investigations at the field of physics sciences" part Mechanics.

关键词： minirobot in-tube motion mechanical system control algorithms on-board microprocessor control schemes

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The μ-Synthesis Applied to a Launcher control

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IFAC Proceedings Volumes 2004年第6期37卷 695-700页

作者： Y. Morita S. Goto Institute of Space and Astronautical Science Japanese Aerospace Exploration Agency 3-1-1 Yoshinodai Sagamihara Kanagawa 229-8510 Japan tel.+81-42-759-8222 fax:+81-42-759-8458 Mitsubishi Precision Co. Ltd

The performance of the M-V rocket attitude control has been validated by the flight results obtained at the first launch of its renewed version, which was successfully conducted in May 2003 to inject Japan's first asteroid sample returner “HAYABUSA” into the planned inter-planetary orbit. The μ-synthesis was applied for the first time ever to the design beyond the reliable H ∞ control to get better robust characteristics against uncertainties of the system parameters as well as precise tracking performance under the limited rigidity. As the plant dynamics has an extremely high order and unstable character, the standard μ-synthesis cannot be directly applied, thus, the standard procedure is modified in a special way in order to make the approach more efficient.

关键词： Robust control control algorithms Attitude control Vibration

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Dynamics and control of free-flying robots in space: A survey

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IFAC Proceedings Volumes 2004年第8期37卷 621-626页

作者： S. Ali A. Moosavian Advanced Robotics & Automated Systems (ARAS) Research Center Department of Mechanical Engineering K.N. Toosi Univ. of Technology Tehran Iran P.O. Box 16767-3381 Fax: (+98) 21 733-4338

Free-flying space manipulator systems, in which robotic manipulators are mounted on a free-flying spacecraft, are envisioned for assembling, maintenance, repair, and contingency operations in space. Nevertheless, even for fixed-base systems, control of mechanical manipulators is a challenging task. This is due to the strong nonlinearities in the equations of motion, and consequently different algorithms have been suggested to control end-effector motion or force, since the early research in robotic systems. In this paper, first a brief review of basic concepts of various algorithms in controlling robotic manipulators is introduced. Then, specific problems related to application of such systems in space and a microgravity environment will be highlighted. Basic issues on the kinematics and dynamics modelling of such systems, trajectory planning and control strategies, experimental studies, and finally cooperation of multiple arm space free-flying robots will be surveyed.

关键词： Space Robotics control algorithms Force control Impedance control

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Problem of Optimal control of the Local System of Aircrafts (LSA) Resources on the Basis of the Game Forecast

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IFAC Proceedings Volumes 2004年第6期37卷 541-545页

作者： E.M. Voronov A.L. Repkin Moscow State Technical University named after N.E. Bauman Moscow Russia

The problem of control optimization of LSA resources under conditions of conflict interaction is analyzed. The problem of LSA resource control within the framework of two-coalition multiobject multi-criteria system subject to the current configurations of coalitions and the conflict-optimal conflict dynamics forecast on the basis of the stable-effective game compromises is considered. Algorithm of optimal resource control is obtained. On the basis of the given algorithms the specialised program system was developed.

关键词： aircraft control control algorithms equilibrium game theory multiobjective optimization multiply-criterion optimization optimal control

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An Adaptive Kalman Filter with Quadrature Encoder Quantisation Compensation

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IFAC Proceedings Volumes 2004年第14期37卷 109-114页

作者： Daniel Luong-Van Jayantha Katupitiya School of Mechanical and Manufacturing Engineering University of New South Wales Sydney Australia

An adaptive Kalman filter was designed to shape the covariance of a quadrature encoder signal to achieve better performance under measurement quantisation. Both temporal and system state measurements were used to predict the measurement noise of the encoder. Results show that the new adaptive filter produces more accurate results while requiring a lower resolution encoder than a similarly designed conventional Kalman filter intended to remove quantisation noise. An example with simulated output is presented to show the performance of the new filter.

关键词： Adaptive filters Analysis of variance control algorithms Estimation algorithms Kalman filters Quantisation errors Quantisation noise

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Three DOF Optimal Thrusters Selection and Modulation for Space Vehicles

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IFAC Proceedings Volumes 2004年第6期37卷 149-154页

作者： N. Silva P. Delpy A. Ducarouge EADS Space Transportation Systems Design and Tests Directorate 66 route de Verneuil 78133 Les Mureaux France

In reaction control thrusters (RCT) propulsed space vehicles the force and/or torque derived from the control law must be translated into thrusters selection and thrusters firing durations. This has often to be done in an optimal way with respect to propellant consumption. Classical catalogue approaches to perform that rely on RCT architectural geometry symmetry properties. When such symmetries are not present at all, use of algorithms such as the linear programming “simplex” one has been advocated. But it presents some risks because the computation duration is not deterministic and no converged solution is granted in a predetermined duration. In-house studies performed at EADS Space Transportation found an optimal catalogue solution for the six DOF (degrees of freedom) problem. This algorithm has been developed for the ATV (Automated Transfer Vehicle) spacecraft. It is based on a precomputed optimal catalogue that is used onboard. However this catalogue depends on the centre of mass and this feature prevents its direct use in the pure attitude control problem. Here it is proposed an adaptation of the 6 DOF optimal catalogue to cope with 3 DOF problems and present some results

关键词： optimization problem attitude control control algorithms

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Improved Performance of Robust MPC with Feedback Model Uncertainty

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IFAC Proceedings Volumes 2004年第1期37卷 875-880页

作者： A.L. Warren T.E. Marlin Department of Chemical Engineering McMaster University Hamilton ON L8S 4L7 Canada

Robust model-predictive controllers use an estimate of model uncertainty in the on-line controller calculation and can be overly conservative for some uncertainty descriptions. This paper discusses the various causes of conservative control with particular emphasis given to the concept of 'closed-loop' probabilistic predictions. A multi-input-multi-output MPC is proposed in which an off-line, non-convex calculation is used to characterize the closed-loop uncertainty a priori. This uncertainty information is incorporated into a convex, quadratic program resulting in a MPC formulation that can be efficiently solved on-line. A distillation column case study demonstrates the benefits of the proposed robust MPC.

关键词： Robust control control algorithms Closed-loop Convex optimization

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Performance directed energy management for main memory and disks

Performance directed energy management for main memory and d...

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Proceedings of the 11th international conference on Architectural support for programming languages and operating systems

作者： Xiaodong Li Zhenmin Li Francis David Pin Zhou Yuanyuan Zhou Sarita Adve Sanjeev Kumar University of Illinois at Urbana-Champaign Intel Labs Santa Clara CA

ISBN: (纸本)9781581138047

Much research has been conducted on energy management for memory and disks. Most studies use control algorithms that dynamically transition devices to low power modes after they are idle for a certain threshold period of time. The control algorithms used in the past have two major limitations. First, they require painstaking, application-dependent manual tuning of their thresholds to achieve energy savings without significantly degrading performance. Second, they do not provide performance guarantees. In one case, they slowed down an application by *** paper addresses these two limitations for both memory and disks, making memory/disk energy-saving schemes practical enough to use in real systems. Specifically, we make three contributions: (1) We propose a technique that provides a performance guarantee for control algorithms. We show that our method works well for all tested cases, even with previously proposed algorithms that are not performance-aware. (2) We propose a new control algorithm, Performance-directed Dynamic (PD), that dynamically adjusts its thresholds periodically, based on available slack and recent workload characteristics. For memory, PD consumes the least energy, when compared to previous hand-tuned algorithms combined with a performance guarantee. However, for disks, PD is too complex and its self-tuning is unable to beat previous hand-tuned algorithms. (3) To improve on PD, we propose a simple, optimization-based, threshold-free control algorithm, Performance-directed Static (PS). PS periodically assigns a static configuration by solving an optimization problem that incorporates information about the available slack and recent traffic variability to different chips/disks. We find that PS is the best or close to the best across all performanceguaranteed disk algorithms, including hand-tuned versions.

关键词： adaptation algorithms control algorithms low power design memory and disk energy management multiple power mode device

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Semi-active Oleodynamic Damper for Earthquake control. Part 2: Evaluation of Performance through Shaking Table Tests

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BULLETIN OF EARTHQUAKE ENGINEERING 2003年第2期1卷 269-301页

作者： Occhiuzzi, Antonio Serino, Giorgio Univ Napoli Federico II Dipartimento Anal & Progettaz Strutturale Naples Italy

Sine sweep and earthquake excitation tests have been performed on a one-story spatial steel frame building equipped with two identical semi-active assemblies described and fully characterized in a companion paper. The tests allowed identifying and validating simple mathematical models of the building in its passive configurations as well as in semi-active operation according to an energy storing and suddenly dissipating algorithm. In order to eliminate or at least attenuate the detrimental effects of control delays due to adopted software, electronic apparatus and mechanical inertia of variable dampers' moving parts, a simple 'sine-fit' prediction method was conceived, evaluated and adopted in subsequent tests. It is shown that, with adequate anticipation of device operation, the selected control algorithm produces a satisfactory reduction of building response compared to that obtained in passive configurations, with overall system efficiency practically independent of the earthquake input and related only to the properties of the semi-active assembly.

关键词： control algorithms control delays prediction methods semi-active control shaking table tests structural control

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