The observability of discrete-event systems is investigated. A discrete-event system G is modeled as the controlled generator of a formal language Lm(G) in the framework of Ramadge and Wonham. To control G, a supervis...
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The observability of discrete-event systems is investigated. A discrete-event system G is modeled as the controlled generator of a formal language Lm(G) in the framework of Ramadge and Wonham. To control G, a supervisor S is developed whose action is to enable and disable the controllable events of G according to a record of occurrences of the observable events of G, in such a way that the resulting closed-loop system obeys some prespecified operating rules embodied in a given language K. A necessary and sufficient condition is found for the existence of a supervisor S such that Lm (S/G) = K. Based on this condition, a solution of the supervisory control and observation problem (SCOP) is obtained. Two examples are provided.
A discrete-event system G is modeled as the controlled generator of a formal language L(G), in the framework of Ramadge and Wonham. In general a centralized global supervisory controller S for G can be defined which g...
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A discrete-event system G is modeled as the controlled generator of a formal language L(G), in the framework of Ramadge and Wonham. In general a centralized global supervisory controller S for G can be defined which generates a suitable closed-loop languageL(S/G). The paper develops the idea of local supervisors Si whose concurrent operation results in the closed-loop language L(ΛSi/G). Conditions are obtained which guarantee that L(ΛSi/G) = L(S/G), namely, distributed local supervision is equivalent to global supervision. For illustration a simple manufacturing system is discussed.
Automatic control of windows shutters as a means for improving the thermal performance of passive houses is explored. In this model the enegy balances at the window surface form the basis for developing a control stra...
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Automatic control of windows shutters as a means for improving the thermal performance of passive houses is explored. In this model the enegy balances at the window surface form the basis for developing a control strategy for the shutters. The model predicts the heat requirements and the hours of overheating experienced in the house subject to temporal variations in radiation fluxes and air temperatures. The results show that automated window shutters can make positive contributions to the design and performance of passive solar houses. An examination into the model equations reveals that for a given house design the effectiveness of the shutters is dictated mainly by the rate as well as the severity of the changes in meteorological variables.
作者：
Cooper, R.A.Control Systems Lab
Department of Electrical and Computer Engineering University of California Santa Barbara CA 93106 United States
This paper is concerned with the directional stability of racing wheelchairs on crown roads. Three types of crown compensators are described and evaluated: the push-pull, the push-push, and the pull-pull. It was found...
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This paper is concerned with the directional stability of racing wheelchairs on crown roads. Three types of crown compensators are described and evaluated: the push-pull, the push-push, and the pull-pull. It was found that the push-push and the push-pull types of compensators have the most desirable characteristics, and were, in general, safer than the pull-pull type. In addition, the equations necessary to specify the minimum spring force required to compensate for the downhill turning moment, were derived and compared to the actual preset forces for the various compensators presently in use. It was found that the force required to maintain directional stability was less than that to deflect the crown compensator. This was due to the preference of athletes for additional stiffness needed for disturbance rejection, and to help compensate for any asymmetry in their stroke kinematics.
In dynamic network identification usually the assumption is made that there is a full rank process noise affecting the network. For large scale networks with many variables this assumption is not realistic as the nois...
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Having criticized the current architecture of Advanced Traveler Information systems （ATISs）, this work discusses a new base of requirements to develop a new paradigm for traffic information systems. It mainly integr...
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Having criticized the current architecture of Advanced Traveler Information systems （ATISs）, this work discusses a new base of requirements to develop a new paradigm for traffic information systems. It mainly integrates three dimensions within a traffic system： drivers＇ pattern of behavior and preferences, urban traffic desires, and capabilities of traffic information service providers. Based on the above, functional segments from several related backgrounds are brought together to structure a new architecture, called Interactive Traveler Information System （ITIS）. The main interactive feature of this new architecture is a two-way communication track between drivers and the traffic information system provider-in fact, a decision on choosing a road at a particular time for an individual will be made based on the utility of both sides. This new configuration consists of driver-side smartphone application, centric traffic prediction, and decision-maker units, which will shape a new approach of decision-making processes. These all work together to satisfy the designated goal of ITIS, which is preserving the Wardrop equilibrium condition in the traffic network level. Finally, we concentrate on a comparison study, which shows a differentiation between performance of the proposed ITIS and the current ATIS model in a real situation. This has been done with simulations of analogical scenarios. The most noticeable advantage of the proposed architecture is not being limited to a saturation limit, and the positive effect of increasing system penetration in the performance of the newly introduced information system. In conclusion, new research subjects are suggested to be carried out.
The method of stabilizing switched systems based on the optimal control is applied,with all modes unstable,for a typical example of the multi-agent ***,the optimal control method for stabilizing switched systems is **...
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The method of stabilizing switched systems based on the optimal control is applied,with all modes unstable,for a typical example of the multi-agent ***,the optimal control method for stabilizing switched systems is *** this purpose,a switching table rule procedure is *** procedure is inspired by the optimal control that identifies the optimal trajectory for the switched *** the next step,the stability of a multi-agent system is studied,considering different unstable connection ***,the optimal control method is successfully applied to an aircraft team,as an example of the multi-agent *** results evaluate and confirm the successful application of this method in the aircraft team example.
new method for calculating the resonant frequency of an equilateral triangular microstrip patch antenna, based on artificial neural networks, is presented The back-propagation algorithm is used to train the networks. ...
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new method for calculating the resonant frequency of an equilateral triangular microstrip patch antenna, based on artificial neural networks, is presented The back-propagation algorithm is used to train the networks. The theoretical resonant frequency results obtained by using this method are in very good agreement with the experimental results reported elsewhere. (C) 1997 John Wiley & Sons, Inc.
In this paper, the robust analysis and design of leader-following output regulation for multi-agent systems described by general linear models is given in presence of timevarying delay and model uncertainty. To this a...
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In this paper, the robust analysis and design of leader-following output regulation for multi-agent systems described by general linear models is given in presence of timevarying delay and model uncertainty. To this aim, a new regulation protocol for the closed-loop multi-agent system under a directed graph is proposed. An important specification of the proposed protocol is to guarantee the leader-following output regulation for uncertain multi-agent systems with both stable and unstable agents. Since many signals can be approximated by a combination of the stationary and ramp signals, the presented results work for adequate variety of the leaders. The analysis and design conditions are presented in terms of certain matrix inequalities. The method proposed can be used for both stationary and ramp leaders. Simulation results are presented to show the effectiveness of the proposed method.
Measured values of the swelling pressure of charged proteoglycans (PG) in solution (Williams RPW, and Comper WD;Biophysical Chemistry 36:223, 1990) and the ionic strength dependence of the equilibrium modulus of PG-ri...
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Measured values of the swelling pressure of charged proteoglycans (PG) in solution (Williams RPW, and Comper WD;Biophysical Chemistry 36:223, 1990) and the ionic strength dependence of the equilibrium modulus of PG-rich articular cartilage (Eisenberg SR, and Grodzinsky AJ;J Orthop Res 3: 148, 1985) are compared to the predictions of two models. Each model is a representation of electrostatic forces arising from charge present on spatially fixed macromolecules and spatially mobile micro-ions. The first is a macroscopic continuum model based an Donnan equilibrium that includes no molecular-level structure and assumes that the electrical potential is spatially invariant within the polyelectrolyte medium (i.e. zero electric field). The second model is based on a microstructural, molecular-level solution of the Poisson-Boltzmann (PB) equation within a unit cell containing a charged glycosaminoglycan (GAG) molecule and its surrounding atmosphere of mobile ions. This latter approach accounts for the space-varying electrical potential and electrical field between the GAG constituents of the PG. In computations involving no adjustable parameters, the PB-cell model agrees with the measured pressure of PG solutions to within experimental error (10%), whereas the ideal Donnan model overestimates the pressure by up to 3-fold. In computations involving one adjustable parameter for each model, the PB-cell model predicts the ionic strength dependence of the equilibrium modulus of articular cartilage. Near physiological ionic strength the Donnan model overpredicts the modulus data by 2-fold, but the two models coincide for low ionic strengths (C-0 < 0.025M) where the spatially invariant Donnan potential is a closer approximation to the PB potential distribution. The PB-cell model result indicates that electrostatic forces between adjacent GAGs predominate in determining the swelling pressure of PG in the concentration range found in articular cartilage (20-80 mg/ml). The PB-cell mod
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