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81.
Arya Aghili Ashtiani Mohammad Bagher Menhaj 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2010,14(6):545-557
In this paper, we study and formulate a BP learning algorithm for fuzzy relational neural networks based on smooth fuzzy norms
for functions approximation. To elaborate the model behavior more, we have used different fuzzy norms led to a new pair of
fuzzy norms. An important practical case in fuzzy relational equations (FREs) is the identification problem which is studied
in this work. In this work we employ a neuro-based approach to numerically solve the set of FREs and focus on generalized
neurons that use smooth s-norms and t-norms as fuzzy compositional operators. 相似文献
82.
Hossam Mohammad Khalil Mohammad El-Bardini 《Expert systems with applications》2011,38(11):14249-14256
The performance of a model-based control system depends strongly on the accuracy of the process model used. LS-SVM is a powerful method for modeling nonlinear systems. The main objective of this paper is to implement a conventional controller based on LS-SVM model for hydraulic motor. An off-line model is first identified based on LS-SVM, then via simulation tests the parameters of the discrete PI-Controller and its velocity-form are obtained then the controller parameters are applied experimentally for the hydraulic motor as a speed controller. The system performance has been evaluated; results show good performance over a wide range of operating conditions and load disturbances. 相似文献
83.
A predictive functional controller based on ARMarkov model structure has been designed to control welding current and arc voltage in a GMAW process. The closed loop system performance is investigated through computer simulations and is compared by those achieved from implementing two commonly used controllers i.e. PI and feedback linearization based PID. The local stability of the closed loop system is analyzed in the presence of uncertainties in the linearized model of the process as well as the control parameters. Finally it is shown that the proposed controller performs like a PI controller along with a pre-filter compensator. 相似文献
84.
In this paper, a new algorithm for solving constrained nonlinear programming problems is presented. The basis of our proposed algorithm is none other than the necessary and sufficient conditions that one deals within a discrete constrained local optimum in the context of the discrete Lagrange multipliers theory. We adopt a revised particle swarm optimization algorithm and extend it toward solving nonlinear programming problems with continuous decision variables. To measure the merits of our algorithm, we provide numerical experiments for several renowned benchmark problems and compare the outcome against the best results reported in the literature. The empirical assessments demonstrate that our algorithm is efficient and robust. 相似文献
85.
86.
Mohammad HammoudAuthor Vitae Sangyeun ChoAuthor VitaeRami MelhemAuthor Vitae 《Journal of Parallel and Distributed Computing》2011,71(6):889-896
This paper describes Constrained Associative-Mapping-of-Tracking-Entries (C-AMTE), a scalable mechanism to facilitate flexible and efficient distributed cache management in large-scale chip multiprocessors (CMPs). C-AMTE enables fast locating of cache blocks in CMP cache schemes that employ one-to-one or one-to-many associative mappings. C-AMTE stores in per-core data structures tracking entries to avoid on-chip interconnect traffic outburst or long distance directory lookups. Simulation results using a full system simulator demonstrate that C-AMTE achieves improvement in cache access latency by up to 34.4%, close to that of a perfect location strategy. 相似文献
87.
Jafar Biazar Behzad Ghanbari Mehdi Gholami Porshokouhi Mohammad Gholami Porshokouhi 《Computers & Mathematics with Applications》2011,61(4):1016-1023
In this paper, He’s homotopy perturbation method is applied to solve non-linear systems of mixed Volterra–Fredholm integral equations. Two examples are presented to illustrate the ability of the method. Also comparisons are made between the Adomian decomposition method and the homotopy perturbation method. The results reveal that He’s homotopy perturbation method is very effective and simple and in these examples leads to the exact solutions. 相似文献
88.
A note on the stability of fractional order systems 总被引:1,自引:0,他引:1
In this paper, a new approach is suggested to investigate stability in a family of fractional order linear time invariant systems with order between 1 and 2. The proposed method relies on finding a linear ordinary system that possesses the same stability property as the fractional order system. In this way, instead of performing the stability analysis on the fractional order systems, the analysis is converted into the domain of ordinary systems which is well established and well understood. As a useful consequence, we have extended two general tests for robust stability check of ordinary systems to fractional order systems. 相似文献
89.
Mohammad H. Mahoor Author Vitae Author Vitae 《Pattern recognition》2009,42(3):445-536
In this paper, we present an approach for 3D face recognition from frontal range data based on the ridge lines on the surface of the face. We use the principal curvature, kmax, to represent the face image as a 3D binary image called ridge image. The ridge image shows the locations of the ridge points around the important facial regions on the face (i.e., the eyes, the nose, and the mouth). We utilized the robust Hausdorff distance and the iterative closest points (ICP) for matching the ridge image of a given probe image to the ridge images of the facial images in the gallery. To evaluate the performance of our approach for 3D face recognition, we performed experiments on GavabDB face database (a small size database) and Face Recognition Grand Challenge V2.0 (a large size database). The results of the experiments show that the ridge lines have great capability for 3D face recognition. In addition, we found that as long as the size of the database is small, the performance of the ICP-based matching and the robust Hausdorff matching are comparable. But, when the size of the database increases, ICP-based matching outperforms the robust Hausdorff matching technique. 相似文献
90.
Active Grid Information Server for grid computing 总被引:1,自引:1,他引:0
We describe the Active Grid Information Server for performing expressive resource discovery searches and resource management
in a grid environment. We represent server meta-data, such as their CPU power, storage capacity and bandwidth as points in
a multi-dimensional space and then express queries as predicates over these points. The design of the system is driven by
its application as a part of the information infrastructure for computational grids. Such grids provide an infrastructure
for sharing computing resources; an information infrastructure is their inherent part which collects resource data and provides
search functionality. Our approach complements current solutions such as MDS by adding Event Condition Action rules and an
ability to efficiently handle dynamic attributes. An Event Condition Action rule-based system can support ad hoc, adaptive,
flexible, and dynamic schedulers that are modifiable at runtime. We evaluate our Active Grid Information Server by evaluating
Event Condition Action rules for termination, confluence, and conflict. 相似文献