Amirkabir University of Technology

About: Amirkabir University of Technology is a education organization based out in Tehran, Iran. It is known for research contribution in the topics: Nonlinear system & Fuzzy logic. The organization has 15254 authors who have published 31165 publications receiving 487551 citations. The organization is also known as: Tehran Polytechnic & Tehran Polytechnic University.

Rational chebyshev tau method for solving higherorder ordinary differential equations

Abstract: An approximate method for solving higher-order ordinary differential equations is proposed. The approach is based on a rational Chebyshev (RC) tau method. The operational matrices of the derivative...

A sequential search-space shrinking using CNN transfer learning and a Radon projection pool for medical image retrieval

Abstract: Closing the semantic gap in medical image analysis is critical. Access to large-scale datasets might help to narrow the gap. However, large and balanced datasets may not always be available. On the other side, retrieving similar images from an archive is a valuable task to facilitate better diagnosis. In this work, we concentrate on forming a search space, consisting of the most similar images for a given query, to be used for a similarity-based search technique in a retrieval system. We propose a two-step hierarchical shrinking search space when local binary patterns are used. Transfer learning via convolutional neural networks is utilized for the first stage of search space shrinking, followed by creating a selection pool using Radon transform for further reduction. The difference between two orthogonal Radon projections is considered in the selection pool to extract more information. The IRMA dataset, from ImageCLEF initiative, containing 14,400 X-ray images, is used to validate the proposed scheme. We report a total IRMA error of 168.05 (or 90.30% accuracy) which is the best result compared with existing methods in the literature for this dataset when real-time processing is considered.

Structural evaluation and mechanical properties of nanostructured Al/B4C composite fabricated by ARB process

Abstract: Nanostructured Al/B 4 C composites with an average grain size of 151 nm were successfully fabricated in the form of sheets, by using accumulative roll bonding (ARB) process. Furthermore, monolithic Al (without B 4 C particles) also was processed by the same method for comparison. The microstructure of the composites, evaluated by optical and scanning electron microscopy, revealed the properly distributed B 4 C particles in the Al matrix. The grain size of the Al matrix, after the final ARB cycle, is studied using Williamson–Hall analysis of X-ray diffraction (XRD) pattern of the deformed sample. Mechanical properties of the specimens were investigated by tensile and hardness tests. The tensile strength and microhardness of the processed samples increased with increasing the number of ARB cycle. Whereas, the elongation dropped abruptly at the first cycle; afterwards, it remained nearly constant in the monolithic samples and increased slightly in the composites.

A particle swarm optimization algorithm for open vehicle routing problem

Abstract: This paper presents a real-value version of particle swarm optimization (PSO) for solving the open vehicle routing problem (OVRP) that is a well-known combinatorial optimization problem. In OVRP a vehicle does not return to the depot after servicing the last customer on a route. A particular decoding method is proposed for implementing PSO for OVRP. In the decoding method, a vector of the customer's position is constructed in descending order. Then each customer is assigned to a route with taking into account feasibility conditions. Finally one-point move has been applied on constructed routes that seem promising to result in a better solution. Experimental evaluations on benchmark data sets demonstrate the competitiveness of the proposed algorithm.