Automotive engines are multivariable system with severe non-linear dynamics, and their modelling and control are challenging tasks for control engineers. Current control of engine used look-up table combined with prop...
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Automotive engines are multivariable system with severe non-linear dynamics, and their modelling and control are challenging tasks for control engineers. Current control of engine used look-up table combined with proportional and integral (PI) control and is not robust to system uncertainty and time varying effects. In this paper the model predictive control strategy is applied to engine air/fuel ratio control using neural network model. The neural network model uses information from multivariables and considers engine dynamics to do multi-step ahead prediction. The model is adapted in on-line mode to cope with system uncertainty and time varying effects. Thus, the control performance is more accurate and robust compared with non-adaptive model based methods. To speed up algorithm calculation, different optimisation algorithms are investigated and performance compared. Finally, the developed method is evaluated on a well-known engine benchmark, a simulated mean value engine model (MVEM). The simulation results demonstrate the effectiveness of the developed method. (C) 2008 Elsevier Ltd. All rights reserved.
We consider the allocation of a limited budget to a set of activities or investments in order to maximize return from investment. In a number of practical contexts (e.g., advertising), the return from investment in an...
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We consider the allocation of a limited budget to a set of activities or investments in order to maximize return from investment. In a number of practical contexts (e.g., advertising), the return from investment in an activity is effectively modeled using an S-curve, where increasing returns to scale exist at small investment levels, and decreasing returns to scale occur at high investment levels. We demonstrate that the resulting knapsack problem with S-curve return functions is NP-hard, provide a pseudo-polynomial time algorithm for the integer variable version of the problem, and develop efficient solution methods for special cases of the problem. We also discuss a fully-polynomial-time approximation algorithm for the integer variable version of the problem. (C) 2007 Elsevier B.V. All rights reserved.
Recent information and communication developments caused that global organizations spread out their markets throughout the world. In this environment, local exclusive markets have been replaced with global competitive...
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Recent information and communication developments caused that global organizations spread out their markets throughout the world. In this environment, local exclusive markets have been replaced with global competitive ones. Therefore, organizations must concentrate on their main operations to survive in such an environment. To do so, managers have intended to cooperate with some financial partners in long-term relations. In this paper, the aim is to develop a fuzzy analytic network process (ANP) model to evaluate the potential suppliers and select the best one(s) with respect to the vendor important factors. Additionally, ANP is developed by fuzzy sets theory to cover the indeterminacy of decisions made in this field. The authors have augmented the model with a non-linear programming model to elicit eigenvectors from fuzzy comparison matrices. Hybridization of these two concepts can model supplier selection problem in all circumstances and reaches the optimal choice. Finally, a numerical sample is used to validate the proposed model. (C) 2009 Elsevier Ltd. All rights reserved.
Electronic commerce encompasses all electronically conducted business activities, operations, and transaction processing. With the development of electronic commerce via Internet, during the past decade, many companie...
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Electronic commerce encompasses all electronically conducted business activities, operations, and transaction processing. With the development of electronic commerce via Internet, during the past decade, many companies have changed the way they connect to and deal with their customers and partners. In this paper we introduce a Geometric programming (GP) based model to analyze the pricing method and the service quality for E-business companies. The proposed method of this paper considers electronic products which are all kinds of products to be sold via web supermarkets. Therefore, they can cover pure digital and also non-digital products. The model proposed in this research work, deals with non-digital goods, which are supplied through web. The resulted non-linear model is directly solved by using Geometric programming (GP) and a closed form of solution is presented. We assume that the demand is influenced by price, marketing and service expenditures. We also assume that the cost of production is affected by demand. We analyze the solution in different cases, in order to study the behavior of the model and for each case numerical examples are used to demonstrate the implementation of our analysis. The sensitivity analysis is also presented at the end to analyze the behavior of the model. (C) 2008 Elsevier Ltd. All rights reserved.
We consider the problem of choosing the levels of a set of advertising media in order to maximize the firm profit when the market is heterogeneous. Advertising efforts affect the demand of the different segments varia...
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We consider the problem of choosing the levels of a set of advertising media in order to maximize the firm profit when the market is heterogeneous. Advertising efforts affect the demand of the different segments variably and we assume that the advertising effects on demand over time are mediated by a vector goodwill variable. A first general advertising decision problem is stated and solved in the non-linear programming framework. A preference index is then obtained for the medium selection problem when each segment demand function is linear in goodwill and each medium advertising cost function is quadratic in its level. Finally the theoretical case of disjoint advertising media is discussed.
The continuous berth allocation problem (BAPC) solves the BAP with continuous berth space and continuous time to optimize the utilization of space and time of the ports A non-linear programming (NLP) model is built an...
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ISBN:
(纸本)9781424447541
The continuous berth allocation problem (BAPC) solves the BAP with continuous berth space and continuous time to optimize the utilization of space and time of the ports A non-linear programming (NLP) model is built and an immune algorithm (IA) is proposed to solve it The effects of the number of vessels, the berth space length and the length of planning time are well controlled so that the approach can handle supper large-scale BAP with promising performance The proposed model and algorithm can be embedded into berth scheduling modules to provide a fast and flexible solution for real-world BAPC to improve the port efficiency
In order to study the optimization algorithm of signal timing of urban intersection under real-time traffic flows, with the target of minimizing the total delay of all entrance lanes of all phases and the restrictions...
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ISBN:
(纸本)9780769538044
In order to study the optimization algorithm of signal timing of urban intersection under real-time traffic flows, with the target of minimizing the total delay of all entrance lanes of all phases and the restrictions of saturation and the minimum green signal time, the non-linear programming model for real-time signal control of urban intersection was constructed and the genetic algorithm for solving the model was proposed. With the model and the genetic algorithm the best scheme of signal timing can be obtained. Through a simulation experiment the application of the model and algorithm was illustrated. The cases of ignoring the restriction of saturation and minimizing the total delay of the key entrance lanes were also analyzed. The analysis results showed that the restriction of saturation should be taken into account and the target function should be constructed on the basis of minimizing the total delay of all entrance lanes of all phases so as to ensure correctness and rationality of the optimizing results.
Enterprises need to develop a process to determine how to find and develop new product ideas and finally, how to successfully introduce them to the marketplace. To address this problem, conceptions of Optimal introduc...
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ISBN:
(纸本)9781424427239
Enterprises need to develop a process to determine how to find and develop new product ideas and finally, how to successfully introduce them to the marketplace. To address this problem, conceptions of Optimal introduction Period and Correlative Profit were presented. Based on the quantitative description of the product life cycle, a non-linear Semi-infinite programming model of new product introduction was proposed. The proposed model was solved by improved Particle Swarm Optimization (PSO) algorithms. Optimal solution of the given example shows that Particle Swarm Optimization has become the hotspot of evolutionary computation because of its excellent performance and simplicity for implement in solving combined optimization problems.
Enterprises need to develop a process to determine how to find and develop new product ideas and finally, how to successfully introduce them to the *** address this problem,conceptions of Optimal Introduction Period a...
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Enterprises need to develop a process to determine how to find and develop new product ideas and finally, how to successfully introduce them to the *** address this problem,conceptions of Optimal Introduction Period and Correlative Profit were *** on the quantitative description of the product life cycle,a non-linear Semi-Infinite programming model of new product introduction was *** proposed model was solved by improved Particle Swarm Optimization(PSO) *** solution of the given example shows that Particle Swarm Optimization has become the hotspot of evolutionary computation because of its excellent performance and simplicity for implement in solving combined optimization problems.
The continuous berth allocation problem （BAPC） solves the BAP with continuous berth space and continuous time to optimize the utilization of space and time of the ports.A non-linear programming （NLP） model is buil...
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The continuous berth allocation problem （BAPC） solves the BAP with continuous berth space and continuous time to optimize the utilization of space and time of the ports.A non-linear programming （NLP） model is built and an immune algorithm （IA） is proposed to solve *** effects of the number of vessels,the berth space length and the length of planning time are well controlled so that the approach can handle supper large-scale BAP with promising *** proposed model and algorithm can be embedded into berth scheduling modules to provide a fast and flexible solution for real-world BAPC to improve the port efficiency.
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