Efficient supply chain management is a crucial imperative for modern, global enterprises. Tactical decision policies based on process control principles have been developed in the literature for managing production-in...
详细信息
This paper addresses the optimization of proof testing policies for safety instrumented systems with redmidant parallel architectures. Testing policies include both the test interval and the test strategy. The approac...
详细信息
This paper presents a new approximation for modelling the time dependent Probability of Failure on Demand (PFD) for parallel redundant safety systems, focussed on the analysis of the impact that different test strateg...
详细信息
In this work, we propose a novel fault tolerant nonlinear model predictive control (FTNMPC) scheme for dealing with control problems associated with an autonomous nonlinear hybrid system (NHS). To begin with, we devel...
详细信息
Efficient supply chain management is a crucial imperative for modern, global enterprises. Tactical decision policies based on process control principles have been developed in the literature for managing production-in...
详细信息
Efficient supply chain management is a crucial imperative for modern, global enterprises. Tactical decision policies based on process control principles have been developed in the literature for managing production-inventory systems and supply chain networks. To be effective these decision policies depend on accurate nominal models. With a discrete-event simulation acting as a “truth model”, we employ system identification techniques to parameterize a nonlinear Partial Differential Equation (PDE) model of the semiconductor manufacturing process. A case study shows that the identified PDE model can accurately predict the output of the discrete-event simulation, but without the high computational burden.
Performance monitoring of model predictive controlsystems (MPC) has received a great interest from both academia and industry. In recent years some novel approaches for multivariate control performance monitoring hav...
详细信息
ISBN:
(纸本)9783902661548
Performance monitoring of model predictive controlsystems (MPC) has received a great interest from both academia and industry. In recent years some novel approaches for multivariate control performance monitoring have been developed without the requirement of process models or interactor matrices. Among them the prediction error approach has been shown to be a promising one, but it is k-step prediction based and may not be fully comparable with the MPC objective that is multi-step prediction based. This paper develops a multi-step prediction error approach for performance monitoring of model predictive controlsystems, and demonstrates its application in an industrial MPC performance monitoring and diagnosis problem.
The Simultaneous Perturbation Stochastic Approximation(SPSA) methodology and a modified SPSA version(MSPSA-K) were investigated for the generation of plantfriendly multi-sinusoidal *** MSPSA-K methodology principally ...
详细信息
The Simultaneous Perturbation Stochastic Approximation(SPSA) methodology and a modified SPSA version(MSPSA-K) were investigated for the generation of plantfriendly multi-sinusoidal *** MSPSA-K methodology principally differs from SPSA in that it perturbs the signal phase parameters in K subsets rather than *** and MSPSA-K provide a flexible,extensible computational framework to incorporate various plant-friendly performance measures into the design of an input signal for experimental design purposes in system *** this paper an objective function comprised of the input signal crest factor,rate of change,acceleration,and output crest factor is presented and applied to a representative case study.A detailed analysis of the tradeoffs between these various performance measures is illustrated by the choice of weighting of the objective function *** proposed method can be applied to signals with an arbitrarily-defined spectrum(in both amplitude and frequency spacing) and is easily implemented.
In this paper, a method to coordinate multi-decentralized model predictive controllers(DMMPC), which is used as a strategy to control the integrated plant through decomposing the total system model into different func...
详细信息
In this paper, a method to coordinate multi-decentralized model predictive controllers(DMMPC), which is used as a strategy to control the integrated plant through decomposing the total system model into different functional sub-models, is proposed. Usually, an integrated plant is also called a large scale systems. The main aim is to relieve the expensive computation load and for improving the flexibility and reliability for operation. How to control and coordinate the possible dynamic coupling and constraints among subsystems has already become an important problem. In order to accomplish the overall objective, coordinating the relationship between optimizer located in upper layer and multi-decentralized MPC controllers located in down layer is a challenging work. A stochastic probability density functions(PDFs) coordination rule is applied to coordinate optimizer with decentralized MPC controllers in the hierarchical control structure. This approach provides the guarantee that local optimal solutions for dominant controlled variables approximate their global optimal solutions under considering uncertainties and interactions among subunits on closed-loop stability condition. As a study case, an integrated plant which consists of two subunits connected via other process and some intermediate tanks under severe constraints while considering maximization economic performance is used to demonstrate feasibility and efficiency of this framework.
The development of control-oriented decision policies for inventory management in supply chains has received considerable interest in recent years, and demand modeling to supply forecasts for these policies is an impo...
详细信息
The development of control-oriented decision policies for inventory management in supply chains has received considerable interest in recent years, and demand modeling to supply forecasts for these policies is an important component of an effective solution to this problem. Drawing from the problem of control-relevant parameter estimation, this paper presents an approach for demand modeling in a productioninventory system that relies on a control-relevant weight to tailor the emphasis of the fit to the intended purpose of the model, which is to provide forecast signals tactical inventory management policies based on Internal Model control. The formulation is multi-objective in nature, allowing the user to emphasize inventory variation, starts change variation, or a weighted combination. By integrating the demand modeling and inventory control problems, it is possible to obtain reducedorder demand models that exhibit superior performance. A systematic approach for generating these weights is presented and the benefits resulting from their use demonstrated on a representative production-inventory system case study.
A recursive procedure is proposed to reduce a set of inequality constraints of high relative order to single constraints of relative order one for a class of uncertain,multi-input nonlinear systems.A modification of a...
详细信息
A recursive procedure is proposed to reduce a set of inequality constraints of high relative order to single constraints of relative order one for a class of uncertain,multi-input nonlinear systems.A modification of a nominal control signal on the newly constructed constraints guarantees robust constraint *** resulting robust invariant controller is applied to the constrained flight and the obstacle avoidance problem of a VTOL helicopter.
暂无评论