In this paper we present an algorithm for medical image retrieval system examines in particular image processing algorithms used for image retrieval based on transformation domain, segmentation and fuzzy logic. This i...
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In this paper we present an algorithm for medical image retrieval system examines in particular image processing algorithms used for image retrieval based on transformation domain, segmentation and fuzzy logic. This is to implement image retrieval algorithm to achieve better classification accuracy for retrieving medical images. It is proposed to implement image segmentation using fuzzy logic with certain improvements for feature extraction with global optimisation using fast Hartley transform (FHT) to reduce the dimensionality of feature space. A new image segmentation algorithm, fuzzy edge detection and segmentation (FEDS) and a bell fuzzy multilayer perceptron (BF-MLP) for classifying images are used. Then BF-MLP is optimised using genetic algorithm (GA) for improved performance.
This paper investigates the robust finite-time control problem for flexible spacecraft attitude tracking maneuver in the presence of model uncertainties and external disturbances. Two robust attitude tracking controll...
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This paper investigates the robust finite-time control problem for flexible spacecraft attitude tracking maneuver in the presence of model uncertainties and external disturbances. Two robust attitude tracking controllers based on finite-time second-order sliding mode control algorithms are presented to solve this problem. For the first controller, a novel second-order sliding mode control scheme is developed to achieve high-precision tracking performance. For the second control law, an adaptive-gain second-order sliding mode control algorithm combing an adaptive law with second-order sliding mode control strategy is designed to relax the requirement of prior knowledge of the bound of the system uncertainties. The rigorous proofs show that the proposed controllers provide finite-time convergence of the attitude and angular velocity tracking errors. Numerical simulations on attitude tracking control are presented to demonstrate the performance of the developed controllers.
Clustering data has a wide range of applications and has attracted considerable attention in data mining and artificial intelligence. However it is difficult to find a set of clusters that best fits natural partitions...
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Clustering data has a wide range of applications and has attracted considerable attention in data mining and artificial intelligence. However it is difficult to find a set of clusters that best fits natural partitions without any class information. In this paper, a method for detecting the optimal cluster number is proposed. The optimal cluster number can be obtained by the proposal, while partitioning the data into clusters by FCM (Fuzzy c-means) algorithm. It overcomes the drawback of FCM algorithm which needs to define the cluster number.. in advance. The method works by converting the fuzzy cluster result into a weighted bipartite network and then the optimal cluster number can be detected by the improved bipartite modularity. The experimental results on artificial and real data sets show the validity of the proposed method.
In this work, we present suitable phase accuracy indicators, which are obtained from the first three obtained eigenvalues of the principal component analysis (PCA) demodulation algorithm. These indicators can be used ...
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In this work, we present suitable phase accuracy indicators, which are obtained from the first three obtained eigenvalues of the principal component analysis (PCA) demodulation algorithm. These indicators can be used in the measuring process to determine a blind phase goodness assessment, without the need of using any ground truth phase information. Therefore, it is possible to perform further actions if required, as obtaining more interferograms or repeat the measure. Additionally, we present simulated and experimental results that support our mathematical analysis and conclusions. A complete MATLAB software package reproducing any result and figure shown in this work is provided in (http://***/fy5EC).
One of the most important problems of reliable communications in shallow water channels is intersymbol interference (ISI) which is due to scattering from surface and reflecting from bottom. Using adaptive equalizers i...
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One of the most important problems of reliable communications in shallow water channels is intersymbol interference (ISI) which is due to scattering from surface and reflecting from bottom. Using adaptive equalizers in receiver is one of the best suggested ways for overcoming this problem. In this paper, we apply the family of selective regressor affine projection algorithms (SR-APA) and the family of selective partial update APA (SPU-APA) which have low computational complexity that is one of the important factors that influences adaptive equalizer performance. We apply experimental data from Strait of Hormuz for examining the efficiency of the proposed methods over shallow water channel. We observe that the values of the steady-state mean square error (MSE) of SR-APA and SPU-APA decrease by 5.8 (dB) and 5.5 (dB), respectively, in comparison with least mean square (LMS) algorithm. Also the families of SPU-APA and SR-APA have better convergence speed than LMS type algorithm.
As far as the increasing number of mixture components in the Gaussian mixture PHD filter is concerned, an iterative mixture component pruning algorithm is proposed. The pruning algorithm is based on maximizing the pos...
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As far as the increasing number of mixture components in the Gaussian mixture PHD filter is concerned, an iterative mixture component pruning algorithm is proposed. The pruning algorithm is based on maximizing the posterior probability density of the mixture weights. The entropy distribution of the mixture weights is adopted as the prior distribution of mixture component parameters. The iterative update formulations of the mixture weights are derived by Lagrange multiplier and Lambert W function. Mixture components, whose weights become negative during iterative procedure, are pruned by setting corresponding mixture weights to zeros. In addition, multiple mixture components with similar parameters describing the same PHD peak can be merged into one mixture component in the algorithm. Simulation results show that the proposed iterative mixture component pruning algorithm is superior to the typical pruning algorithm based on thresholds.
STEPPING MOTORS ARE USED IN numerous applications because of their low manufacturing cost and simple open-loop position control capabilities. It is well known that their energy efficiency is low, although the actual e...
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STEPPING MOTORS ARE USED IN numerous applications because of their low manufacturing cost and simple open-loop position control capabilities. It is well known that their energy efficiency is low, although the actual efficiency values are generally not available. Moreover, the bulk of the stepping motors are driven in a non-optimal way, e.g., in an open loop with a maximum current to avoid step loss and, thus, with low efficiency. In this article, the impact of the control algorithm on the efficiency of the motor is analyzed, measured, and discussed. The basic open-loop full-, half-, and microstepping algorithms are considered together with a more advanced vector control algorithm. For each algorithm, the torque/current optimization is discussed.
An algorithm for adaptive pulse signal shaping is proposed for the tag response signal with large fluctuations of radio frequency identification (RFID) tag test systems, which has not been addressed in the literature ...
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An algorithm for adaptive pulse signal shaping is proposed for the tag response signal with large fluctuations of radio frequency identification (RFID) tag test systems, which has not been addressed in the literature for the scenario. To verify the proposed algorithm, an experimental platform implemented with a field programmable gate array (FPGA) is set up based on National Instruments. The experimental results show that the algorithm is sufficient for correcting the RFID tag response pulse signal even for the signal with severe signal distortion.
A novel wide-pipeline low-density parity-check (LDPC) decoder approach for the worldwide interoperability for microwave access (WiMAX) standard (802.16e) is proposed for execution on field-programmable gate arrays (FP...
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A novel wide-pipeline low-density parity-check (LDPC) decoder approach for the worldwide interoperability for microwave access (WiMAX) standard (802.16e) is proposed for execution on field-programmable gate arrays (FPGAs), using a high-level synthesis tool to reduce the development effort and design validation time that generates a wide-pipeline architecture. Optimised open computing language (OpenCL)-based kernels are developed and the integration of distinct configurations of single instruction multiple data and compute units to increase the level of parallelism are analysed. The decoding throughput surpasses the minimal requirements of 75 Mbit/s, a key figure of merit that ranks the design with other very large-scale integration-based approaches. Furthermore, extra precision is deployed with 8-bit fixed-point arithmetic, delivering superior bit error rate performance and lower error floor regions.
A wireless indoor positioning system using white LED lights is proposed. The time difference of arrival technique is employed and the phase differences between the received signals are determined to develop a position...
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A wireless indoor positioning system using white LED lights is proposed. The time difference of arrival technique is employed and the phase differences between the received signals are determined to develop a positioning algorithm which can estimate the receiver location with a mean localisation error as low as 1 mm in a room of dimensions 5 x 5 x 3 m. Through simulations, it is identified that the optimum receiver height where localisation error gets minimised is between 2.5 and 3 m from the ceiling which corresponds well with the typical dimensions of a room.
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