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91.
We consider a system of Maxwell’s and Landau-Lifshitz-Gilbert equations describing magnetization dynamics in micromagnetism. The problem is discretized by a convergent, unconditionally stable finite element method. A multigrid preconditioned Uzawa type method for the solution of the algebraic system resulting from the discretized Maxwell’s equations is constructed. The efficiency of the method is demonstrated on numerical experiments and the results are compared to those obtained by simplified models. 相似文献
92.
Efficient monitoring of parametric context-free patterns 总被引:1,自引:0,他引:1
Patrick O’Neil Meredith Dongyun Jin Feng Chen Grigore Roşu 《Automated Software Engineering》2010,17(2):149-180
Recent developments in runtime verification and monitoring show that parametric regular and temporal logic specifications
can be efficiently monitored against large programs. However, these logics reduce to ordinary finite automata, limiting their
expressivity. For example, neither can specify structured properties that refer to the call stack of the program. While context-free
grammars (CFGs) are expressive and well-understood, existing techniques for monitoring CFGs generate large runtime overhead
in real-life applications. This paper demonstrates that monitoring parametric CFGs is practical (with overhead on the order of 12% or lower in most cases). We present a monitor synthesis algorithm for CFGs based on an
LR(1) parsing algorithm, modified to account for good prefix matching. In addition, a logic-independent mechanism is introduced
to support matching against the suffixes of execution traces. 相似文献
93.
Cost estimation and effort allocation are the key challenges for successful project planning and management in software development.
Therefore, both industry and the research community have been working on various models and techniques to accurately predict
the cost of projects. Recently, researchers have started debating whether the prediction performance depends on the structure
of data rather than the models used. In this article, we focus on a new aspect of data homogeneity, “cross- versus within-application
domain”, and investigate what kind of training data should be used for software cost estimation in the embedded systems domain.
In addition, we try to find out the effect of training dataset size on the prediction performance. Based on our empirical
results, we conclude that it is better to use cross-domain data for embedded software cost estimation and the optimum training
data size depends on the method used. 相似文献
94.
C. Başyigit Iskender Akkurt S. Kilincarslan A. Beycioglu 《Neural computing & applications》2010,19(4):507-513
The compressive strength of heavyweight concrete which is produced using baryte aggregates has been predicted by artificial
neural network (ANN) and fuzzy logic (FL) models. For these models 45 experimental results were used and trained. Cement rate,
water rate, periods (7–28–90 days) and baryte (BaSO4) rate (%) were used as inputs and compressive strength (MPa) was used as output while developing both ANN and FL models.
In the models, training and testing results have shown that ANN and FL systems have strong potential for predicting compressive
strength of concretes containing baryte (BaSO4). 相似文献
95.
Francisco J. Rubio Francisco J. Valero Jose Luis Suñer Vicente Mata 《Asian journal of control》2010,12(4):468-479
This paper addresses the solution of smooth trajectory planning for industrial robots in environments with obstacles using a direct method, creating the trajectory gradually as the robot moves. The presented method deals with the uncertainties associated with the lack of knowledge of kinematic properties of intermediate via‐points since they are generated as the algorithm evolves looking for the solution. Several cost functions are also proposed, which use the time that has been calculated to guide the robot motion. The method has been applied successfully to a PUMA 560 robot and four operational parameters (execution time, computational time, distance travelled and number of configurations) have been computed to study the properties and influence of each cost function on the trajectory obtained. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
96.
Dan Selişteanu Monica Roman Dorin Şendrescu 《Simulation Modelling Practice and Theory》2010,18(9):1297-1313
This paper deals with the problem of modelling and on-line estimation of kinetics for a biomethanation process. This bioprocess is in fact a wastewater biodegradation process with production of methane gas, which takes place inside a Continuous Stirred Tank Bioreactor. The reaction scheme and the analysis of biochemical phenomena inside the bioreactor are used in order to obtain a nonlinear dynamic model of the bioprocess, by means of the pseudo Bond Graph method. Two nonlinear estimation strategies are developed for the identification of unknown kinetics of the bioprocess. First, an estimator is developed by using a state observer based technique. Second, an observer based on high-gain approach is designed and implemented. Several numerical simulations are performed in order to analyse and compare the behaviour and the performance of the proposed estimators. 相似文献
97.
In this study, a novel OFF-set based direct-cover Exact Minimization Algorithm (EMA) is proposed for single-output Boolean functions represented in a sum-of-products form. To obtain the complete set of prime implicants covering the given Target Minterm (ON-minterm), the proposed method uses OFF-cubes (OFF-minterms) expanded by this Target Minterm. The amount of temporary results produced by this method does not exceed the size of the OFF-set. In order to achieve the goal of this study, which is to make faster computations, logic operations were used instead of the standard operations. Expansion OFF-cubes, commutative absorption operations and intersection operations are realized by logic operations for fast computation. The proposed minimization method is tested on several classes of benchmarks and then compared with the ESPRESSO algorithm. The results show that the proposed algorithm obtains more accurate and faster results than ESPRESSO does. 相似文献
98.
99.
100.
In this paper, an automatic diagnosis system for diabetes on Linear Discriminant Analysis (LDA) and Morlet Wavelet Support Vector Machine Classifier: LDA–MWSVM is introduced. The structure of this automatic system based on LDA-MWSVM for the diagnosis of diabetes is composed of three stages: The feature extraction and feature reduction stage by using the Linear Discriminant Analysis (LDA) method and the classification stage by using Morlet Wavelet Support Vector Machine (MWSVM) classifier stage. The Linear Discriminant Analysis (LDA) is used to separate features variables between healthy and patient (diabetes) data in the first stage. The healthy and patient (diabetes) features obtained in the first stage are given to inputs of the MWSVM classifier in the second stage. Finally, in the third stage, the correct diagnosis performance of this automatic system based on LDA–MWSVM for the diagnosis of diabetes is calculated by using sensitivity and specificity analysis, classification accuracy, and confusion matrix, respectively. The classification accuracy of this system was obtained at about 89.74%. 相似文献