2012 2nd International eConference on Computer and Knowledge Engineering (ICCKE)

Iris segmentation is the principal task of Iris based biometric identification systems. Always the low contrast between pupil and iris always affects on accuracy of detecting boundary between them. In order to increasing the accuracy of boundary detecting, we propose a new technique using a difference function and a factor matrix. We also enhance the technique to detect the pupil and iris as ellip... View full abstract»

The human motion analysis is an attractive topic in biometric research. Common biometrics is usually time-consuming, limited and collaborative. These drawbacks pose major challenges to recognition process. Recent researches indicate people have considerable ability to recognize others by their natural walking. Therefore, gait recognition has obtained great tendency in biometric systems. Gait analy... View full abstract»

Digital watermarking has been proposed as a way to claim ownership. In this paper, a new approach in digital image watermarking based on discrete wavelet transform (DWT) and singular value decomposition (SVD) is presented. We use compositional pattern producing networks (CPPNs) to make a very compact representation of watermark. Using Neuro Evolution of Augmenting Topologies (NEAT) will evolve the... View full abstract»

The recognition of face images is a complicated problem. Face images are often sufferedfrom variations in brightness, head rotation, facial emotions and so on. Besides, amazing abilities of human brain in face recognition in the presence of these variations, contribute to design face recognition systems based on procedure of human brain. Surveying the recognition and perceptual system of human, sh... View full abstract»

In the recent years there has been an interest within the physics community in the properties of networks of many types. Graph clustering is the process of identifying the network structure in terms of grouping the vertices of a graph into clusters taking into consideration the edge structure of the graph that in such a way there should be many edges within each cluster and relatively few between ... View full abstract»

In this paper, a new method for Farsi font recognition based on combination of features is proposed. The features are extracted and combined from textures of size 128×128 using SRF and Wavelet transform. Wavelet and SRF are naturally different methods of feature extraction, so their errors have low correlation. In this condition, the combination of these features which are both applicable for text... View full abstract»

A super-resolution reconstruction from single image algorithm designed for license plate recognition is proposed in this paper. Low resolution images database is generated by down sampling and adding white Gaussian noise to the super resolution license plate database. The low-resolution image can be viewed as a down sampled version of a high-resolution image, where its patches are assumed to have ... View full abstract»

Shape is one of the main features in content-based image retrieval (CBIR). This paper proposes a novel CBIR technique based on shape feature. This technique uses the distances between the boundary points of a shape and the smallest rectangle that covers it. The proposed technique is a Fourier based technique and it is invariant to translation, scaling and rotation. The retrieval performance betwee... View full abstract»

In this paper three new approaches based on smoothed nonlinear energy operator (SNEO), fractal dimension (FD) and standard deviation to detect the spikes for noisy neuronal data are proposed. In many cases, especially when there are several noise sources, these methods may not be acceptable as spike detectors. To overcome these problems, we use Savitzky-Golay filter and discrete wavelet transform ... View full abstract»

Electroencephalogram (EEG) is generally known as a non-stationary signal. Dividing a signal into the epochs within which the signals can be considered stationary, segmentation, is very important in many signal processing applications. Noise often influences the performance of an automatic signal segmentation system. In this article, a new approach for segmentation of the EEG signals based on singu... View full abstract»

One of the most significant practical challenges for face recognition is a likeness of faces which leads to a big problem in classification of different classes. To tackle this problem, we present a novel method based on similarity of each face with other faces using the Pearson correlation coefficients. Besides, another problem is variability in lighting intensity which its physics are difficult ... View full abstract»

In this paper the particle swarm optimization (PSO) technique is used to find an optimal solution for the selective harmonic elimination (SHE) problem in PWM AC/AC voltage regulators. For this kind of voltage controllers, SHE leads to nonlinear and transcendental equations; as a result, solving them by conventional numerical methods highly depends on proper selection of initial values. The propose... View full abstract»

This paper proposes a new fuzzy-based direct power control (FDPC) for doubly fed induction generator (DFIG)-based wind energy conversion systems. In the proposed method, the required rotor voltages are directly calculated based on fuzzy controller, stator voltage, rotor speed and some machine parameters. The switching table and hysteresis comparator used in conventional DPC are replaced by PWM mod... View full abstract»

The four-leg voltage source inverter (VSI) is becoming increasingly popular in power applications due to its superior performance characteristics such as relatively low dc-bus voltage and capability to handle unbalanced or nonlinear load currents. With unbalanced load condition, to balance such a system, a neutral connection is needed to control each phase voltage independently. Average large sign... View full abstract»

In this paper a robust intelligent controller is adopted in order to fulfil maximum power point tracking (MPPT) algorithm for permanent magnet synchronous generator (PMSG) with the application of wind turbines. Conventional linear PI controller is simple and easy to implement but it has the drawback of dependence on system parameters especially in a wind energy conversion system with large amount ... View full abstract»

Simple structure, quick, and robust response of direct torque control (DTC) make it attractive in ac drives. However, in sensorless applications, precise estimation of rotor speed is a crucial issue as well as the torque and flux estimation. In this paper an adaptive flux observer is introduced with stator current and flux vector components as state variables and rotor speed as an unknown paramete... View full abstract»

This paper presents an optimum switching pattern for the space vector modulation (SVM) of matrix converters based on a genetic algorithm. The possibility of choosing the sequence of active duty cycles, and the ability to allocate the duration of the inactive duty cycle to each one of the zero duty cycles in a matrix converter SVM, provide some degrees of freedom in designing of the switching patte... View full abstract»

One of the features of the Next Generation Wireless Networks (NGWNs) is its heterogeneous communication environment. Heterogeneous networks are ranging from wireless WAN, LAN, MAN and PAN. The most important parameters in this regard are different data rates and coverage of these networks. In this paper, we propose an evolvable fuzzy logic-based algorithm for managing handover process in heterogen... View full abstract»