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Results for “centralized and decentralized regulations”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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4 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

Centralized, decentralized, and independent control of a flexible manipulator on a flexible base

The dynamics and control of a flexible manipulator arm with payload mass on a flexible base in space are considered. The controllers are provided by one torquer at the center of the base and one torquer at the connection joint of the robot and the base. The nonlinear dynamics of the system is modeled by applying the finite element method and Lagrangian formula. Three control strategies are considered and compared, i.e., centralized control, decentralized control, and independent control. All these control designs are based on the linear quadratic regulator theory. A mathematical decomposition is used in the decentralization process so that the coupling between the subsystems is weak, while a physical decomposition is used in the independent control design process. For both the decentralized and the independent controls, the stability of the overall linear system is checked before a numerical simulations is initiated. Two numerical examples show that the response of the independent control system are close to those of the centralized control system, while the responses of the decentralized control system are not.

Li, Feiyue↗
NASA NTRS2003

Regulation in the Air: Price and Frequency Cap

Despite deregulation on the air-transportation markets, many connections are still operated by a single operator. Regulation is thus a central issue in this industry. There is however a great concern for the (possibly negative) consequences of price regulation on the quality of services. We argue that both aspects should be considered jointly and propose a mechanism that allow to decentralize the optimal structure of services in this industry. The regulatory procedure is robust to the introduction of heterogeneity in the travellers' valuation of the connections' frequency.

deVillemeur, Etienne Billette↗
NASA NTRS1988

Decentralized model reference adaptive control of large flexible structures

A decentralized model reference adaptive control (DMRAC) method is developed for large flexible structures (LFS). The development follows that of a centralized model reference adaptive control for LFS that have been shown to be feasible. The proposed method is illustrated using a simply supported beam with collocated actuators and sensors. Results show that the DMRAC can achieve either output regulation or output tracking with adequate convergence, provided the reference model inputs and their time derivatives are integrable, bounded, and approach zero as t approaches infinity.

Lee, Fu-Ming↗
NASA NTRS2000

Health Hazard Assessment and Toxicity Clearances in the Army Acquisition Process

The United States Army Materiel Command, Army Acquisition Pollution Prevention Support Office (AAPPSO) is responsible for creating and managing the U.S. Army Wide Acquisition Pollution Prevention Program. They have established Integrated Process Teams (IPTs) within each of the Major Subordinate Commands of the Army Materiel Command. AAPPSO provides centralized integration, coordination, and oversight of the Army Acquisition Pollution Prevention Program (AAPPP) , and the IPTs provide the decentralized execution of the AAPPSO program. AAPPSO issues policy and guidance, provides resources and prioritizes P2 efforts. It is the policy of the (AAPPP) to require United States Army Surgeon General approval of all materials or substances that will be used as an alternative to existing hazardous materials, toxic materials and substances, and ozone-depleting substances. The Army has a formal process established to address this effort. Army Regulation 40-10 requires a Health Hazard Assessment (HHA) during the Acquisition milestones of a new Army system. Army Regulation 40-5 addresses the Toxicity Clearance (TC) process to evaluate new chemicals and materials prior to acceptance as an alternative. U.S. Army Center for Health Promotion and Preventive Medicine is the Army's matrixed medical health organization that performs the HHA and TC mission.

Macko, Joseph A., Jr.↗