In order to reduce the torque ripple of SR motor drive, this work proposes a new methodology based on the converter, controller, and motor modelling, associated with a geneticalgorithm optimisation model which uses t...
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In order to reduce the torque ripple of SR motor drive, this work proposes a new methodology based on the converter, controller, and motor modelling, associated with a geneticalgorithm optimisation model which uses the electromagnetic vibration data to calculate the best firing angles for the inverter power switches. To implement the power electronic motor drive model and the optimisation procedure, it was used, respectively, with coupled FEM simulations resources and a MATLAB Script. In this work, they were tested with two inverter commutation strategies whose values were validated through the comparison with the experimental results. The simulated and experimental values converge in the same direction, validating the proposed methodology.
In response to the challenge of mitigating flight delays, this study introduces an innovative solution that encompasses the prediction of delay durations for existing flights and the subsequent optimization of ground ...
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In response to the challenge of mitigating flight delays, this study introduces an innovative solution that encompasses the prediction of delay durations for existing flights and the subsequent optimization of ground service processes based on these predictions. The indirect forecasting of flight delays is achieved through the construction of a random forest model, exhibiting a remarkable 100% accuracy when considering a 15-minute standard for flight delays. In light of the delay prediction outcomes, distinct delay coefficients are assigned to individual flights, facilitating the development of a ground service optimization model through the application of a geneticalgorithm. Within the geneticalgorithm optimization framework, significant enhancements have been implemented in the gene encoding of the initial population, incorporating a segmented encoding approach. Employing this refined model to optimize the service sequence and duration of ground service vehicles for all flights culminates in the notable accomplishment of achieving zero delays for the entire set of flights.
During the process of mechanism kinematic structure enumeration, isomorphism identification of graphs is an important and complicated problem. The problem is known to be a NP-complete problem. In this paper, according...
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During the process of mechanism kinematic structure enumeration, isomorphism identification of graphs is an important and complicated problem. The problem is known to be a NP-complete problem. In this paper, according to the mechanism kinematic chain isomorphism identification criteria, a highly efficient hybrid genetic algorithm model is proposed for isomorphism identification. The model method is coupled with geneticalgorithm, optimal choice, and optimal crossover operation. It shows a quick convergence rate of the late operation and can avoid convergence to local optimum. Simulation results show that the hybrid algorithm is more rapid and effective compared with simple geneticalgorithm and the improved neural network algorithm.
A scanning electron microscope (SEM) is a sophisticated equipment employed for fine imaging of a variety of surfaces. in this study, prediction models of SEM were constructed by using a generalized regression neural n...
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A scanning electron microscope (SEM) is a sophisticated equipment employed for fine imaging of a variety of surfaces. in this study, prediction models of SEM were constructed by using a generalized regression neural network (GRNN) and geneticalgorithm (GA). The SEM components examined include condenser lens I and 2 and objective lens (coarse and fine) referred to as CL1, CL2, OL-Coarse, and OL-Fine. For a systematic modeling of SEM resolution (R), a face-centered Box-Wilson experiment was conducted. Two sets of data were collected with or without the adjustment of magnification. Root-mean-squared prediction error of optimized GRNN models are GA 0.481 and 1.96 x 10(-12) for non-adjusted and adjusted data, respectively. The optimized models demonstrated a much improved prediction over statistical regression models. The optimized models were used to optimize parameters particularly under best tuned SEM environment. For the variations in CL2 and OL-Coarse, the highest R could be achieved at all conditions except a larger CL2 either at smaller or larger OL-Coarse. For the variations in CL1 and CL2, the highest R was obtained at all conditions but larger CL2 and smaller CL1. (C) 2009 Elsevier Ltd. All rights reserved.
The important role of quality of service (QoS) in deployment of a resilient dense wavelength division multiplexing (DWDM) backbone for global networks requires critical design-phase planning optimisation. The design i...
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The important role of quality of service (QoS) in deployment of a resilient dense wavelength division multiplexing (DWDM) backbone for global networks requires critical design-phase planning optimisation. The design issues of resilient DWDM networks for bandwidth and delay sensitive applications of dedicated path protection are addressed. A geneticalgorithm (GA) model has been developed to solve the routing and wavelength assignment problem using binary variable-length chromosome encoding under two different schemes of bandwidth optimisation (BOS) and delay optimisation (DOS). The performance of the new GA-based resiliency model has been evaluated for four benchmark networks: PAN EUROPEAN, COST239, NSFNET and ARPA2. Simulation results show a superior capability and efficiency for the model to solve this complex, multi-constraint and nondeterministic polynomial-hard problem for BOS and DOS. The nonlinear nature of this process reveals a significant sensitivity for optical layer network topology on the optimum-design QoS. The results also demonstrate that the PAN EUROPEAN network shows the highest flexibility for primary path design, NSFNET for the secondary path and ARPA2 comes with the lowest design flexibility for both primary and secondary paths.
Antipredator vigilance is a major component of defenses against predators for many prey species. For group foragers, such vigilance is predicted by models to decrease with group size reflecting better predator detecti...
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Antipredator vigilance is a major component of defenses against predators for many prey species. For group foragers, such vigilance is predicted by models to decrease with group size reflecting better predator detection ability and risk dilution in larger groups. Influential vigilance models for group foragers have made simplifying and often quite restrictive assumptions. Prey species, for instance, are expected to search for resources in groups of fixed sizes although frequent changes in group sizes often occur while foraging. Groups of prey in the same area are also assumed to be attacked independently, but predators could sequentially target several local groups after a failed attempt. I propose a framework in which prey animals can form groups by joining feeding neighbors and also adjust their vigilance in these groups of varying sizes. Predators can attack one of the many groups that occur in the same area and can also target groups of specific sizes. I used a geneticalgorithm approach to simultaneously tackle joining and vigilance choices by prey individuals. I show that joining tendencies and the effect of group size on vigilance can vary with forager population size, the spatial distribution of resources, and predator attack tactics. The modeling framework adopted here generates several novel predictions about vigilance and joining tendencies for group foragers, and highlights the importance of considering the availability and vulnerability of prey groups in the same habitat when predicting antipredator vigilance.
Background: Recently, mass spectrometry data have been mined using a geneticalgorithm to produce discriminatory models that distinguish healthy individuals from those with cancer. This algorithm is the basis for clai...
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Background: Recently, mass spectrometry data have been mined using a geneticalgorithm to produce discriminatory models that distinguish healthy individuals from those with cancer. This algorithm is the basis for claims of 100% sensitivity and specificity in two related publicly available datasets. To date, no detailed attempts have been made to explore the properties of this geneticalgorithm within proteomic applications. Here the algorithm's performance on these datasets is evaluated relative to other methods. Results: In reproducing the method, some modifications of the algorithm as it is described are necessary to get good performance. After modification, a cross-validation approach to model selection is used. The overall classification accuracy is comparable though not superior to other approaches considered. Also, some aspects of the process rely upon random sampling and thus for a fixed dataset the algorithm can produce many different models. This raises questions about how to choose among competing models. How this choice is made is important for interpreting sensitivity and specificity results as merely choosing the model with lowest test set error rate leads to overestimates of model performance. Conclusions: The algorithm needs to be modified to reduce variability and care must be taken in how to choose among competing models. Results derived from this algorithm must be accompanied by a full description of model selection procedures to give confidence that the reported accuracy is not overstated.
In this passage, we intend to determinate the specific searching plan for lost aircraft on the basis of big data application. First, we cope with Maximum Flow Problem by BFS, in order to the determination of cruise ro...
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ISBN:
(纸本)9781510812055
In this passage, we intend to determinate the specific searching plan for lost aircraft on the basis of big data application. First, we cope with Maximum Flow Problem by BFS, in order to the determination of cruise route. Then, in the determination of numbers of search planes and warships along each path, we can use the genetic algorithm model.
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