Iranian Journal of Electrical and Electronic Engineering
Volume:14 Issue: 2, Jun 2018

The tremor injury is one of the common symptoms of Parkinson's disease. The patients suffering from Parkinson's disease have difficulty in controlling their movements owing to tremor. The intensity of the disease can be determined through specifying the range of intensity values of involuntary tremor in Parkinson patients. The level of disease in patients is determined through an empirical range of 0-5. In the early stages of Parkinson, resting tremor can be very mild and intermittent. So, diagnosing the levels of disease is difficult but important since it has only medication therapy. The aim of this study is to quantify the intensity of tremor by the analysis of electromyogram signal. The solution proposed in this paper is to employ a polynomial function model to estimate the Unified Parkinson's Disease Rating Scale (UPDRS) value. The algorithm of Fast Orthogonal Search (FOS), which is based on identification of orthogonal basic functions, was utilized for model identification. In fact, some linear and nonlinear features extracted from wrist surface electromyogram signal were considered as the input of the model identified by FOS, and the model output was the UPDRS value. In this research, the proposed model was designed based on two different structures which have been called the single structure and parallel structure. The efficiency of designed models with different structures was evaluated. The evaluation results using K-fold cross validation approach showed that the proposed model with a parallel structure could determine the tremor severity of the Parkinson's disease with accuracy of 99.25% ±0.41, sensitivity of 97.17% ±1.9 and specificity of 99.72% ±0.18.

A null steering GPS antenna array is designed in this paper. In the proposed method, the exact full wave antenna radiation properties with the effect of mutual couplings and nearby scatterers are considered to calculate the array steering vector, precisely. Although the proposed method is not constrained by the array geometry and the antenna element specifications, a five patch antenna elements with planar array geometry is designed and simulated as an anti jam GPS antenna example. The simulation results show the importance of the mutual coupling effects. Moreover, the results verify the proposed method ability to encounter with the multiple GPS jammer sources. Finally, the effect of jammer power is investigated which shown that the antenna performance is increased by jammer power enhancement.

In this paper, we propose a new path-based multicast algorithm that is called Row/Column-First algorithm. The proposed algorithm constructs a set of multicast paths to deliver a multicast message to all multicast destination nodes. The set of multicast paths are all of row-first or column-first subcategories to maximize the multicast performance. The selection of row-first or column-first approaches is done based on the location of multicast source node i.e., how the multicast source is far from right/left and top/bottom margins of the mesh network. In this way, the proposed algorithm improves two performance criteria i.e., traffic and communication latency as compared with the well-known Column-Path multicast algorithm. In order to evaluate the proposed algorithm, an analytical model is developed to estimate the mentioned performance criteria. The modeling and simulation results show improvement of 10 and 20 percent on traffic and communication latency respectively for Row/Column-First algorithm as compared to the Column-Path algorithm.

This work introduces a new and simple method for adjusting the gain of current mirror. The major advantage of the proposed architecture is that, unlike the conventional variable gain current mirror, it does not need the change of the biasing current to adjust current gain. Therefore, the power dissipation remains constant in all of the gain settings. In addition, the proposed variable gain current mirror have linear-in-dB gain control characteristic, simple structure, and small occupied area. The gain of the current mirror can be simply varied from 1.3dB to 21dB while the 3-dB bandwidth of the circuit remains around 12.3MHz or 33.6MHz at operation frequency range of 1.9MHz-14.2MHz and 6.6MHz-40.2MHz respectively. The proposed circuit draws negligible power of 6.9µW from 1.8V supply voltage. The simulation results of designed variable gain current mirror in 0.18μm standard CMOS technology confirms the effectiveness of the proposed circuit.

The potentiality of millimter-wave (mm-wave) double-drift region (DDR) impact avalanche transit time (IMPATT) diodes based on a wide bandgap (WBG) semiconductor material, Gallium Phosphide (GaP) has been explored in this paper. A non-sinusoidal voltage excited (NSVE) large-signal simulation method has been used to study the DC and high frequency characteristics of DDR GaP IMPATTs dsigned to operate at mm-wave atmospheric window frequencies such as 94, 140 and 220 GHz. Results show that the DDR GaP IMPATTs are capable of delivering significantly higher RF power at the above mentioned window frequencies as compared to the DDR IMPATTs based on the conventional narrow bandgap (NBG) base materials such as Si, GaAs and InP.

In this article, a fabulous method for database retrieval is proposed. The multi-resolution modified wavelet transform for each of image is computed and the standard deviation and average are utilized as the textural features. Then, the proposed modified bit-based color histogram and edge detectors were utilized to define the high level features. A feedback-based dynamic weighting of shape, color and textural features composition produce a resistant feature vectors for image retrieval and recall. A comprehensive and unified matching scheme based on matrix error rate technique was accomplished for similarity of image and retrieval procedure. The feature vectors size in our algorithm is the least one evaluated to the different techniques. Furthermore, the calculation time of previously published techniques is much more than the presented algorithm which is a benefit in proposed retrieval method. The experimental results illustrates that novel algorithm obtains more precious in retrieval and the efficiency in evaluating with the other techniques and algorithms at Corel color image database.

This paper introduces four new resistorless circuits of first-order current-mode all-pass filter (CMAPF) based on dual-X current conveyor transconductance amplifier (DXCCTA). All the four circuits use a single DXCCTA and a capacitor for their realization. The main features of the proposed CMAPFs are: use of minimum active and passive components, resistorless realization, electronically adjustable pole frequency, easily cascadable, good sensitivity performance with respect to active and passive elements, low total harmonic distortion of output current (0.74%) and good operating frequency range (39.2 MHz). The non-ideal analysis of the proposed circuits has also been explored. Moreover, two applications of the proposed first-order CMAPF in terms of second order CMAPF and current-mode quadrature oscillator are also presented. HSPICE simulations have been carried out with 0.18 µm CMOS process parameters to validate the proposed circuits.

This work studies the effects of dynamic threshold design techniques on the speed and power of digital circuits. A new dynamic threshold transistor structure has been proposed to improve performances of digital circuits. The proposed switched-capacitor dynamic threshold PMOS (SC-DTPMOS) scheme employs a capacitor along with an NMOS switch in order to effectively reduce the threshold voltage of a PMOS transistor. The proposed structure improves the propagation delay of a circuit and is much suitable for those circuits with high switching factor. Post layout simulation results using TSMC 180 nm CMOS technology at 0.2V supply voltage shows 45% improvement in delay as well as 25% less power consumption at the cost of only 53% more occupied area.

Distributed generation (DG) has been widely used in distribution network to reduce the energy losses, improve voltage profile and system reliability, etc. The location and capacity of DG units can influence on probability of protection mal-operation in distribution networks. In this paper, a novel model for DG planning is proposed to find the optimum DG location and sizing in radial distribution networks. The main purpose of the suggested model is to minimize the total cost including DG investment and operation costs. The operation costs include the cost of energy loss, the cost of protection coordination and also the mal-operation cost. The proposed DG planning model is implemented in MATLAB programming environment integrated with DIgSILENT software. The simulation results conducted on the standard 38-bus radial distribution network confirm the necessity of incorporating the protection coordination limits in the DG planning problem. Additionally, a sensitivity analysis has been carried out to illustrate the significance of considering these limits.

This paper presents a new framework based on modified EMD method for detection of single and multiple PQ issues. In modified EMD, DWT precedes traditional EMD process. This scheme makes EMD better by eliminating the mode mixing problem. This is a two step algorithm; in the first step, input PQ signal is decomposed in low and high frequency components using DWT. In the second stage, the low frequency component is further processed with EMD technique to get IMFs. Eight features are extracted from IMFs of low frequency component. Unlike low frequency component, features are directly extracted from the high frequency component. All these features form feature vector which is fed to PNN classifier for classification of PQ issues. For comparative analysis of performance of PNN, results are compared with SVM classifier. Moreover, performance of proposed methodology is also validated with noisy PQ signals. PNN has outperformed SVM for both noiseless and noisy PQ signals.