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101.
Milan Petrík 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2010,14(10):1053-1057
Alsina, Frank, and Schweizer posed a question whether a non-trivial convex combination of triangular norms can ever be a triangular norm. In this paper we deal with the class of strict t-norms with well-defined first partial derivatives along their zero borders. We show that the answer to the question is negative for certain couples of such t-norms and we state out possible further research. 相似文献
102.
The accelerating interaction between technology and tourism has changed radically the efficiency and effectiveness of tourism organizations, as well as how consumers interact with organizations. In this study, a Web based intelligent framework for travel agencies is proposed that offers customers a fast and reliable response service in a less costly manner. The proposed framework integrates case-based reasoning (CBR) system with a well-known multi criteria decision making (MCDM) technique, namely Analytic Hierarchy Process, to enhance the accuracy and speed in case matching in tourism destination planning. The integration of two techniques enables taking advantages of their strengths and complements each other’s weaknesses. A case study is performed to demonstrate how this framework can facilitate intelligent decision support by retrieving best-fitted responses for customers. 相似文献
103.
Sustainable supply chain management (SSCM) provides economic, social end environmental requirements in material and service flows occurring between suppliers, manufacturers and customers. SSCM structure is considered as a prerequisite for a sustainable success. Thus designing an effective SCM structure provides competitive advantages for the companies. In order to achieve an effective design of this structure, it is possible to apply quality function deployment (QFD) approach which is successfully applied as an effective product and system development tool. This study presents a decision framework where analytic network process (ANP) integrated QFD and zero-one goal programming (ZOGP) models are used in order to determine the design requirements which are more effective in achieving a sustainable supply chain (SSC). The first phase of the QFD is the house of quality (HOQ) which transforms customer requirements into product design requirements. In this study, after determining the sustainability requirements named customer requirements (CRs) and design requirements (DRs) of a SSC, ANP is employed to determine the importance levels in the HOQ considering the interrelationships among the DRs and CRs. Furthermore ZOGP approach is used to take into account different objectives of the problem. The proposed method is applied through a case study and obtained results are discussed. 相似文献
104.
Martin Vohralík 《Journal of scientific computing》2011,46(3):397-438
We study in this paper a posteriori error estimates for H
1-conforming numerical approximations of diffusion problems with a diffusion coefficient piecewise constant on the mesh cells
but arbitrarily discontinuous across the interfaces between the cells. Our estimates give a global upper bound on the error
measured either as the energy norm of the difference between the exact and approximate solutions, or as a dual norm of the
residual. They are guaranteed, meaning that they feature no undetermined constants. (Local) lower bounds for the error are
also derived. Herein, only generic constants independent of the diffusion coefficient appear, whence our estimates are fully
robust with respect to the jumps in the diffusion coefficient. In particular, no condition on the diffusion coefficient like
its monotonous increasing along paths around mesh vertices is imposed, whence the present results also include the cases with
singular solutions. For the energy error setting, the key requirement turns out to be that the diffusion coefficient is piecewise
constant on dual cells associated with the vertices of an original simplicial mesh and that harmonic averaging is used in
the scheme. This is the usual case, e.g., for the cell-centered finite volume method, included in our analysis as well as
the vertex-centered finite volume, finite difference, and continuous piecewise affine finite element ones. For the dual norm
setting, no such a requirement is necessary. Our estimates are based on H(div)-conforming flux reconstruction obtained thanks to the local conservativity of all the studied methods on the dual grids,
which we recall in the paper; mutual relations between the different methods are also recalled. Numerical experiments are
presented in confirmation of the guaranteed upper bound, full robustness, and excellent efficiency of the derived estimators. 相似文献
105.
Tarık Çakar 《Journal of Intelligent Manufacturing》2011,22(4):481-490
A neuro-dominance rule (NDR) for single machine total weighted tardiness problem with unequal release date is presented by
the author. To obtain the NDR, backpropagation artificial neural network (BPANN) has been trained using 10,000 data and also
tested using 10,000 another data. Inputs of the trained BPANN are starting date of the first job (t), processing times (pi and pj), due dates (di and dj), weights of the jobs (wi and wj) and ri and rj release dates of the jobs. Output of the BPANN is a decision of which job should precede. Training set and test set have
been obtained using Adjusted Pairwise Interchange method. The proposed NDR provides a sufficient condition for local optimality.
It has been proved that if any sequence violates the NDR then violating jobs are switched according to the total weighted
tardiness criterion. The proposed NDR is compared to a number of competing heuristics (ATC, COVERT, EDD, SPT, LPT, WDD, WSPT,
WPD, CR, FCFS) and meta heuristics (simulated annealing and genetic algorithms) for a set of randomly generated problems.
The problem sizes have been taken as 50, 70, 100. NDR is applied 270,000 randomly generated problems. Computational results
indicate that the NDR dominates the heuristics and meta heuristics in all runs. Therefore, the NDR can improve the upper and
lower bounding schemes. 相似文献
106.
Comparison of different classifier algorithms for diagnosing macular and optic nerve diseases 总被引:1,自引:1,他引:0
Abstract: The aim of this research was to compare classifier algorithms including the C4.5 decision tree classifier, the least squares support vector machine (LS-SVM) and the artificial immune recognition system (AIRS) for diagnosing macular and optic nerve diseases from pattern electroretinography signals. The pattern electroretinography signals were obtained by electrophysiological testing devices from 106 subjects who were optic nerve and macular disease subjects. In order to show the test performance of the classifier algorithms, the classification accuracy, receiver operating characteristic curves, sensitivity and specificity values, confusion matrix and 10-fold cross-validation have been used. The classification results obtained are 85.9%, 100% and 81.82% for the C4.5 decision tree classifier, the LS-SVM classifier and the AIRS classifier respectively using 10-fold cross-validation. It is shown that the LS-SVM classifier is a robust and effective classifier system for the determination of macular and optic nerve diseases. 相似文献
107.
Differentiating types of muscle movements using a wavelet based fuzzy clustering neural network 总被引:1,自引:1,他引:0
Abstract: The electromyographic signals observed at the surface of the skin are the sum of many small action potentials generated in the muscle fibres. After the signals are processed, they can be used as a control source of multifunction prostheses. The myoelectric signals are represented by wavelet transform model parameters. For this purpose, four different arm movements (elbow extension, elbow flexion, wrist supination and wrist pronation) are considered in studying muscle contraction. Wavelet parameters of myoelectric signals received from the muscles for these different movements were used as features to classify the electromyographic signals in a fuzzy clustering neural network classifier model. After 1000 iterations, the average recognition percentage of the test was found to be 97.67% with clustering into 10 features. The fuzzy clustering neural network programming language was developed using Pascal under Delphi. 相似文献
108.
Hub location problems deal with finding the location of hub facilities and with the allocation of demand nodes to these located hub facilities. In this paper, we study the single allocation hub covering problem over incomplete hub networks and propose an integer programming formulation to this end. The aim of our model is to find the location of hubs, the hub links to be established between the located hubs, and the allocation of non-hub nodes to the located hub nodes such that the travel time between any origin–destination pair is within a given time bound. We present an efficient heuristic based on tabu search and test the performance of our heuristic on the CAB data set and on the Turkish network. 相似文献
109.
Adrian Blumer Jan Novák Ralf Habel Derek Nowrouzezahrai Wojciech Jarosz 《Computer Graphics Forum》2016,35(7):461-473
Aggregate scattering operators (ASOs) describe the overall scattering behavior of an asset (i.e., an object or volume, or collection thereof) accounting for all orders of its internal scattering. We propose a practical way to precompute and compactly store ASOs and demonstrate their ability to accelerate path tracing. Our approach is modular avoiding costly and inflexible scene‐dependent precomputation. This is achieved by decoupling light transport within and outside of each asset, and precomputing on a per‐asset level. We store the internal transport in a reduced‐dimensional subspace tailored to the structure of the asset geometry, its scattering behavior, and typical illumination conditions, allowing the ASOs to maintain good accuracy with modest memory requirements. The precomputed ASO can be reused across all instances of the asset and across multiple scenes. We augment ASOs with functionality enabling multi‐bounce importance sampling, fast short‐circuiting of complex light paths, and compact caching, while retaining rapid progressive preview rendering. We demonstrate the benefits of our ASOs by efficiently path tracing scenes containing many instances of objects with complex inter‐reflections or multiple scattering. 相似文献
110.
In this study, a hybrid intelligent solution system including neural networks, genetic algorithms and simulated annealing has been proposed for the inverse kinematics solution of robotic manipulators. The main purpose of the proposed system is to decrease the end effector error of a neural network based inverse kinematics solution. In the designed hybrid intelligent system, simulated annealing algorithm has been used as a genetic operator to decrease the process time of the genetic algorithm to find the optimum solution. Obtained best solution from the neural network has been included in the initial solution of genetic algorithm with randomly produced solutions. The end effector error has been reduced micrometer levels after the implementation of the hybrid intelligent solution system. 相似文献