International Journal of Circuits, Systems and Signal Processing


ISSN: 1998-4464
Volume 6, 2012

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Issue 1, Volume 6, 2012


Title of the Paper: Self-Timed Multi-Operand Addition

Authors: P. Balasubramanian, D. A. Edwards, W. B. Toms

Pages: 1-11

Abstract: Self-timed addition of multiple data operands is discussed in this paper. Though there are various works in the existing literature targeting dual-operand addition, multiple operand addition has not been exclusively dealt with. In this context, this paper throws light on two important concepts – i) presenting a bit-partitioning scheme that divides input data into groups where additions within the individual groups are carried out in parallel, and ii) proposing novel and efficient (4:2) logic compressor realizations corresponding to weak-indication and robust early output timing regimes. An analysis of the efficiency of addition for a significant case study involving 8 input data, each of size 32-bits, is performed with carry save adders or logic compressors employed for the input field partitions. The simulation results show the proposed early propagative compressor design effectively optimizing the power-delay-area design envelope.


Title of the Paper: Self-Organizing Map Weights and Wavelet Packet Entropy for Speaker Verification

Authors: K. Daqrouq, A. Al-Qawasmi, O. Daoud, W. Al-Sawalmeh

Pages: 12-20

Abstract: With the growing trend toward distant security verification systems for telephone banking, biometric security measures and other remote access applications, Automatic Speaker Verification (ASV) has attracted a great attention in recent years. The complexity of ASV system and its verification time depends on the number of feature vector elements. Therefore, in this paper, we concentrate on optimizing dimensionality of feature space by selecting the weights of Self-Organizing Map (WSOM) Neural Network (NNT) for text-independent speaker verification system. This is accomplished by decreasing the number of feature vector elements of individual speaker obtained by using wavelet packet (WP) Shannon, Sure, and log energy in conjunction with energy indices ( 1020 elements) to 64 elements by WSOM. To investigate the performance of the proposed WSOM and wavelet packet entropies (SOMWPE) method, two other verification methods are proposed: Gaussian mixture model based method (GMMWPE) and K-Means clustering based method (KMWPE). The results indicated that a better verification rate for the speaker-speaker system was accomplished by SOMWPE. Better result was achieved (94.34%) in case of the speaker-imposter verification system. In case of white Gaussian noise (AWGN), it was observed that the SOMWPE system is generally more noise-robust than GMMWPE and KMWPE systems.


Title of the Paper: Genetic Algorithms Based Fuzzy Speed Controllers for Indirect Field Oriented Control of Induction Motor Drive

Authors: Moulay Rachid Douiri, Mohamed Cherkaoui, Ahmed Essadki

Pages: 21-28

Abstract: In this paper the genetic algorithms is applied to automate and optimize the fuzzy controller design process. To do this, the normalization parameters, membership functions and decision table are converted into binary bit string. This optimization requires a predefined objective function. The task of such a design algorithm is the modification of the existing knowledge and at the same time, the investigation of new feasible structures. The proposed approach in this paper is employed for the speed control of an induction motor drive with indirect field oriented control.


Title of the Paper: DSP Based Simulator for Field Oriented Control of the Surface Permanent Magnet Synchronous Motor Drive

Authors: Abdel-Karim Daud, Basim Alsayid, Arafat Zaidan

Pages: 29-37

Abstract: Permanent Magnet Synchronous Motors (PMSM) have wide applications in industry, especially in AC servo drives. Digital Signal Processors (DSP) has greatly enhanced the potential of PMSM servo drive in such applications. Most of controller drives the PMSM by using the field-orientation control mode. This method laid the motor at maximum theoretical performance. This paper presents the field oriented vector control scheme for permanent magnet synchronous motor (PMSM) drives, where current controller followed by hysteresis comparator is used. The field oriented vector control, that regulates the speed of the PMSM, is provided by a quadrature axis current command developed by the speed controller. The simulation includes all realistic components of the system. This enables the calculation of currents and voltages in different parts of the voltage source inverter (VSI) and motor under transient and steady state conditions. Implementation has been done in MATLAB/Simulink. A study of hysteresis control scheme associated with current controllers has been made. Experimental results of the PMSM control using TMS320F24X DSP board are presented. The speed of the PMSM is successfully controlled in the constant torque region. Experimental results show that the PMSM exhibits improved speed stability especially in very low speed range. The validity and usefulness of the proposed control scheme are verified through simulation and experimental results.


Title of the Paper: Positioning Error Reduction by the Use of Multiple GPS Terminal

Authors: Yuki Odaka, Shinya Takano, Yusuke In, Masakazu Higuchi, and Hitomi Murakami

Pages: 38-48

Abstract: Recently, studies of location identification by mobile phone have been attracting a lot of attention, and it is applied to various applications. Now, when mobile phones have become ubiquitous terminals, many mobile phone GPS terminals may be unevenly distributed within local locations. Our study examines the error characteristics of terminals that are located within a short distance. We used GPS loggers in this experiment because we intended to investigate the change effect of satellites. In this paper, we consider that positioning errors in GPS terminals depend on the difference in the number of satellites used for positioning calculation and the satellite numbers. In addition, we perform theoretical analysis of GPS errors and study the error characteristics of GPS loggers and mobile phone GPS.


Title of the Paper: Contribution to Modification of Graph Cut Method and Its Implementation in the Image Segmentation

Authors: I. Zolotova, P. Karch

Pages: 49-56

Abstract: This article presents the implementation of methods to improve Graph cut segmentation. An initialization contour in the form of approximate tracing of the object for segmentation is used for initialization. The proposed modifications are designed to change the value setting of edges in the graph, implementation of iterative method and optimization of efficiency and accuracy. The modifications bring less dependence on user-set constants of Graph cut segmentation and thereby simplify user interaction. The experimental verification of the proposed modifications is tested for the efficiency, accuracy and repeatability of these modifications.


Title of the Paper: On One Approach to Parameters Evaluation of Energy Minimizing Image Restoration Methods

Authors: Igor V. Gribkov, Peter P. Koltsov, Nikolay V. Kotovich, Alexander A. Kravchenko, Alexander S. Koutsaev, Andrey S. Osipov, Alexey V. Zakharov

Pages: 57-64

Abstract: We study input parameters of energy methods for image restoration, when a restored image is obtained after minimization of an integral functional. Although such a functional is global, only few pixels in a small neighborhood of any pixel on the initial image can influence on the corresponding pixel on the restored image. Conversely, any pixel on the initial pixel affects some pixels in a neighborhood of the corresponding pixel on the restored image. We call these neighborhoods "influence areas" and propose a technique for their calculation and their visualization on computer screen. The whole testing technique based upon this approach is applied to a couple of known image restoration methods. The parameters of these methods, ensuring their better performance, are found.


Title of the Paper: The Judgment of Document Similarities Orthogonal Transformations and Improvement of the Property

Authors: Atraru Matsuzawa, Masakazu Higuchi, Gamba Jonah, Shuji Kawasaki, Hitomi Murakami

Pages: 65-74

Abstract: The objective of this work is to propose a new method to evaluate similarity of documents using Orthogonal transformations and examine its performance experimentally expecting its application to plagiarism detection. The numbers are transformed by the Fourier, Cosine, Haar Wavelet and Hadamard system. As a measure of the similarity of two documents, the correlation of them is used. As a result of the experiment, it turns out that Fourier transformation is effective for certain similar documents presumed to be produced by plagiarism. Therefore we focus on Fourier system. In case single-byte characters and double-byte characters is intermixed there is a problem. That is result of document similarities is low thought documents are similar. Against this problem we propose character-code-conversion. To standardize double-byte characters by character-code-conversion, the precision of judge rise. Furthermore, we decided threshold of each length of sentences.


Title of the Paper: 3D Ad-Hoc Sensor Networks Based Localization and Risk Assessment of Buried Landfill Gas Source

Authors: Saurav Mitra, Siddhartha P. Duttagupta, Kushal Tuckley, Samsul Ekram

Pages: 75-86

Abstract: Anaerobic decomposition of landfill garbage produces gases like CH4 and H2S at subsurface. These gases diffuse through the foundation and come out to pollute the indoor building environment above. CH4 is highly flammable and causes explosion whereas H2S causes equipment failure and significant pulmonary ailments in human beings over long term exposure. This work focuses on 3D ad-hoc wireless sensor network (WSN) based localization and risk assessment of such a gas source buried at subsurface. Experiments are performed to emulate the gas diffusion process at underground. Experiments also help to determine gas propagation constants over the surface. Higher precision of the threestep maximum likelihood (ML) based source localization method enhances the accuracy of source risk assessment process. Simulation results indicate that the proposed localization algorithms with limited sensor node mobility offer higher accuracy of estimation using lesser network resources. Finally, we propose an analysis for remote source concentration measurement. This help estimate severity of threat possessed by the buried landfill gas source. Also a method is proposed for 3D ad-hoc WSN based source location estimation with obstructed paths for surface gas propagation.


Title of the Paper: Fast Periodic Auto and Cross Correlation Algorithms for an Orthogonal Set of Real-Valued Perfect Sequences from the Huffman Sequence

Authors: Takahiro Matsumoto, Hideyuki Torii, Shinya Matsufuji

Pages: 87-96

Abstract: A perfect sequence has the optimal periodic autocorrelation function where all out-of-phase values are zero, and an orthogonal set has orthogonality that the periodic correlation function for any pair of distinct sequences in the set takes zero at the zero shift. The real-valued perfect sequences of period N = 2^n are derived from a real-valued Huffman sequence of length 2^ν + 1 with ν >= n whose out-of-phase aperiodic autocorrelation function takes zero except at the left and right shift-ends. This paper proposes fast periodic auto- and cross-correlation algorithms for an orthogonal set of real-valued perfect sequences of period 2^n. As a result, the number of multiplications and additions can be suppressed on the order N log_2 N.


Title of the Paper: Design of Telemetry and Telecommand Subsystem of a Micro-Satellite Based on Industrial-Level Chips

Authors: Jie Liu, Hao Zhang, Wei Zheng, Liuguo Yin

Pages: 97-104

Abstract: Miniaturized satellites characterized with small size, low weight, cheap designs, short development period, and flexible launching way have been recognized as cost effective solutions for universities, Businesses and even individuals to develop satellites. However, the design of highly reliable subsystem based on commercial level or industrial level VLSI chips is the key challenging problem in micro-satellite production. In this paper, a redundant design scheme is proposed for designing the telemetry and telecommand (TTC) subsystem of a micro satellite based on industrial-level VLSI chips, and the reliability of the subsystem with the proposed design scheme is also analyzed. It is shown with analytical results that with redundant design scheme the reliability of a CAN Bus could be effectively improved, and the redundant CAN bus based on low-level VLSI chips could be applied to the TTC subsystem of a micro-satellite.


Title of the Paper: Perceptually Motivated Bayesian Estimators With Generalized Gamma Distribution Under Speech Presence Probability

Authors: Atanu Saha, Tetsuya Shimamura

Pages: 105-112

Abstract: In this paper, we propose a family of Bayesian estimators for single channel speech enhancement. The Bayesian estimators, which utilize the cost function of the log-spectral amplitude (LSA) estimator, are based on generalized Gamma distribution under speech presence probability. The cost function obtained from the LSA estimator is weighted by psychoacoustically motivated speech distortion measure to take advantage of the perceptual interpretation. The experimental results show that the proposed estimators provide less residual noise and better speech quality compared to the traditional state-of-the-art estimators.


Title of the Paper: Analog SPICE Implementation of Multi-Frequency Ultrasound System

Authors: Imamul Muttakin, Nik Muhamad Arif, Syed Mohd Nooh, Eko Supriyanto

Pages: 113-121

Abstract: The emergence of ultrasound applications raises the need of reliable transducer to comply with that purpose. As polymer material being popular in medical ultrasound, there are chances to combine it with former piezoelectric ceramic material in designing diagnostic transducer to get hybrid characteristics required for multi-frequency application. In this work, SPICE model of ceramic-polymer piezoelectric has been described. Using Leach’s approach, the modeled transducer covers triple peaks resonances. Electro-acoustic circuit simulation level shows that by hybridization, characteristics of both materials are providing a satisfying performance for multi-frequency transducer. With signal conditioner circuit, complete analog system for ultrasound has also been developed. As initial, transducer test for ceramic and polymer model were generated. By filtering and amplifying frequency range from 1 MHz until 10 MHz, the system offers wideband medical ultrasonic acceptance. With -5 to +5 voltage head-room, it gives smooth result of ultrasound signal for medical purposes.


Title of the Paper: Study of Non-Stationary Temperature Fields in Printed Circuit Boards During Separation by Cutting

Authors: D. Janacova, H. Charvatova, K. Kolomaznik, V. Vasek, P. Mokrejs, Z. Dvorak, R. Drga

Pages: 122-129

Abstract: Nowadays, growth of electronic waste represents serious global problem. Therefore, ways of its recycling are searched. In the paper we deal with the printed circuit boards recycling. We focused on study of a cutting as an alternative method of conductive ways from plastic board separation as one of stages of the printed circuit board recycling procedure. For this purpose we formulated mathematic model of the cutting process and next we used its analytical solution for its modeling by mathematic software Maple. The obtained results confirm energy intensity of the cutting process.


Issue 2, Volume 6, 2012


Title of the Paper: A Diffusion Based Wave Computing Algorithm for Real Time Edge Detection

Authors: Mojtaba Karami, Mohammad Rahmati, Reza Safabakhsh

Pages: 131-142

Abstract: In this paper, a new wave computing algorithm for edge detection in real images is introduced. This algorithm is suitable for real time applications due to the parallel processing capabilities of CNN. The new algorithm is based on the wave computing concept, using diffusion for noise reduction and weak edge elimination and trigger wave to emphasize the strong edges in the image. The proposed algorithm finds edge maps in eight directions and these maps are summed to produce final edge map. The performance of our proposed algorithm is evaluated and compared with different diffusion models using the Berkeley dataset BSDS300 with its benchmark. Experimental results demonstrate superiority of our proposed for real images.


Title of the Paper: Hardware Parallel Architecture of a 3D Surface Reconstruction: Marching Cubes Algorithm

Authors: Mili Manel, Mahmoud Bouraoui, Akil Mohamed, Bedoui Med Hédi

Pages: 143-150

Abstract: In this paper we present a study of the algorithmic and architectural exploration methodology for a parallelism of the 3D reconstructing algorithm (Marching Cubes) and its optimized implementation on FPGA. We aim at defining a parallel multiprocessor architecture implementing this algorithm in an optimal way and Elementary Processor (EP) architecture dedicated to this algorithm. We use the SynDEx tool which adapts the AAA (Algorithm Architecture Adequacy) methodology, to find a good compromise between the computing power, the functionality of each PE, the optimization constraint (time, area), and the parallelization efficiency. Then, we describe a first implementation of PE on FPGA.


Title of the Paper: Optimal IIR Filter Design using Novel Particle Swarm Optimization Technique

Authors: Suman Kumar Saha, Rajib Kar, Durbadal Mandal, Sakti Prasad Ghoshal

Pages: 151-162

Abstract: This paper demonstrates the application of an evolutionary heuristic search technique called Novel Particle Swarm Optimization (NPSO) for the optimal design of 6th and 8th order low pass and band pass Infinite Impulse Response (IIR) filters. Conventional particle swarm optimization (PSO) has been modified with the attractive features of cognitive information, ( and ) and named as NPSO. NPSO helps to speed up the convergence by means of non-advancement of particle to position. It finds near optimal solution in terms of a set of filter coefficients. The effectiveness of this algorithm is justified with a comparative study of some well established algorithms, namely, Real coded Genetic Algorithm (RGA) and conventional Particle Swarm Optimization (PSO) with a superior outcome for the designed 6th and 8th order IIR low pass and band pass filters. Simulation results affirm that the proposed NPSO algorithm outperforms its counterparts not only in terms of quality output i.e. sharpness at cut-off, pass band ripple and stop band attenuation but also in convergence speed with assured stability.


Title of the Paper: Performances Comparative Study of Field Oriented Control (FOC) and Direct Torque Control (DTC) of Dual Three Phase Induction Motor (DTPIM)

Authors: Radhwane Sadouni, Abdelkader Meroufel

Pages: 163-170

Abstract: We present in this paper a comparative study between two most popular control strategies of electrical machines: field oriented control (FOC) and direct torque control (DTC) for controlling a Dual Three Phase Induction Motor. The comparison is based on several criteria including: static and dynamic performance, structure and implementation complexity, decoupling, torque and current ripple, etc... Also, we present in this study the advantages and disadvantages of each control scheme, the best is the one that better meets the requirements.


Title of the Paper: Harmonic Filters Design of a Power System with Specially Connected Transformers Using Hybrid Differential Evolution Method

Authors: Yao-Hung Chan, Chi-Jui Wu

Pages: 171-178

Abstract: This paper is used to investigate the harmonic filters planning of a power system with three-phase to two-phase specially connected transformers. The hybrid differential evolution (HDE) method is used to obtain the filter parameter values. The migrant and accelerating operations embedded in HDE are used to overcome the traps of local optimal solutions and problems of time consumption. The design purposes are to minimize the total demand distortion of harmonic currents and total harmonic distortion of voltages. The reactive power compensation and constraints of individual harmonics are also considered. Three design cases are compared to demonstrate the design results. The study results shows that the scheme type of three-phase to two-phase specially connected transformers have significant effects on the harmonic distribution. The design approach can greatly reduce the harmonic distortion.


Title of the Paper: Generating Passive Systems from Recursively Defined Polynomials

Authors: Luigi Fortuna, Mattia Frasca

Pages: 179-188

Abstract: In single-input single-output linear time-invariant systems, and in particular in filter modelling and design, some properties of the system (such as shaped frequency responses) are achieved by using polynomials of particular types for the design of the system transfer function. In this paper it is shown that single-input single-output linear time-invariant systems having as transfer function the ratio between two successive polynomials recursively defined have particular properties. In particular, if the ratio between successive polynomials of either Fibonacci or Lucas type is considered, loss-less systems are achieved, while starting from Jacobsthal or Morgan-Voyce polynomials relaxation systems are defined. Furthermore, it is also shown that transfer functions obtained by considering either the ratio between a Fibonacci polynomial of order n and a Lucas polynomial of order n or between a Fibonacci polynomial of order n and a Lucas polynomial of order n-1 multiplied by the complex variable s are also loss-less.


Issue 3, Volume 6, 2012


Title of the Paper: High Density Impulse Noise Removal Using Modified Switching Bilateral Filter

Authors: T. Veerakumar, S. Esakkirajan, Ila Vennila

Pages: 189-196

Abstract: In this paper, we propose a modified switching bilateral filter to remove impulse noise and enhance the image details in an image. The proposed filter consists of noise detection stage and noise reduction stage. The noise detection is based on the gray level [Lmin, Lmax]. The noise reduction is based on the global trimmed mean with modified switching bilateral filter. This modified switching bilateral filter effectively removes the salt and pepper noise at very high noise density. Simulation results show that our proposed filter achieves high peak signal to noise ratio, Image Enhancement factor and correlation factor. Even though the time complexity of proposed filter is greater than the other impulse noise filters, the performance of the proposed filter with respect to noise removal is better than the existing filters.


Title of the Paper: An Efficient Pitch Estimation Method Using Windowless and Normalized Autocorrelation Functions in Noisy Environments

Authors: M. A. F. M. Rashidul Hasan, Tetsuya Shimamura

Pages: 197-204

Abstract: In this paper, a pitch estimation method is proposed based on windowless and normalized autocorrelation functions from noise corrupted speech observations. Instead of the input speech signal, we utilize its windowless autocorrelation function for obtaining the normalized autocorrelation function. The windowless autocorrelation function is a noise-reduced version of the input speech signal where the periodicity is more apparent with enhanced pitch peak. The performance of the proposed pitch estimation method is compared in terms of gross pitch error with the recent other related methods. A comprehensive evaluation of the pitch estimation results on male and female voices in white and pink noises shows the superiority of the proposed method over some of the related methods under low levels of signal-to-noise ratio.


Title of the Paper: Neural Predictive Control of IUT based on Focused Time Delay Structure

Authors: M. Sadeghi, M. Gholami

Pages: 205-212

Abstract: Neural network Controller methodology is a nonlinear control fashion equipped with a novel method of Neural Predictive Controller (NPC) as an intelligent optimizer that in this cased based on the Focused Time Delay Neural Network (FTDNN) for modeling the nonlinear system and performing the optimization procedure. In case of prediction and control, two individual strategies are concerned for the current projects. The first is FTDNN procedure modeling the dynamics of system. The other is an optimization unit xpected for minimization of optimization index. In this regards the Intelligent Universal Transformer (IUT) which will be raised in the Advanced Distribution of Automation (ADA) are discussed. IUT is an electrical key point introducing as a heart of ADA in case of Intelligent Electrical Devices (IED). ADA is the state of art, comprising the flexible electrical architecture and open communication construction empowered synergistically each other to contribute the tomorrow’s distribution automation. IUT construction relay on the bases of power electronic devices that employs the modern technologies of high voltage-low current solid-State equipment to cope with the deficiencies of current traditional transformers. So the IUT topology emphasizes on rectifiers, converters and PWM inverters in both input-output stages. These could be controlled via the intelligent control fashion for enhancing the robustness and stability of system in condition of variation take place. The proposed predictive control technique is a moderated control strategy using artificial neural networks to investigate the three phase power PWM converters of IUT for designing the current and voltages regulators in input-output stages. These result in the smooth regulation in IUT control and improve the system characteristics under load and source disturbances. At first the FTDNN model the power inverter dynamics of IUT. Then the optimization procedure takes place to minimize the optimization index for constructing the duty cycle of inverters as a control signals.


Title of the Paper: Sampling Procedure of the Arithmetic Operations with two Binary Markov Process Realizations

Authors: Y. Goritskiy, V. Kazakov

Pages: 213-220

Abstract: The sampling procedure of the arithmetic operation with two Binary Markov Processes (BMP) is considered in detail, especially for the sum of BMP. The result of the sum can have four or three states. In the first case there is a Markovian process, in the second case the process is non Markovian. We investigate sampling procedure of any realization of this case. The investigation method takes into account the probability of the state omission and probability densities functions of staying times in each state. We obtain the algorithm for choosing of sampling intervals for each state. They are different. One non trivial example is given. The obtained results are generalized for other arithmetic operations: the multiplication and division. One rather important variant of the application of such processes in the random field model is given at the final paragraph.


Title of the Paper: Improving Automatic Feature Detection from LIDAR Intensity by Integration of LIDAR Height Data and True Orthoimage from Digital Camera

Authors: Lamyaa Gamal El-Deen Taha Solyman

Pages: 221-230

Abstract: Airborne laser scanning (ALS) and multispectral photography have synergic capabilities for information extraction. Feature detection methodologies are very important in the context of spatial data capture and updating for GIS applications. These methodologies can be based on either LIDAR data or photogrammetric data or even on a combination between them. True orthoimages were generated by orthorectification of digital camera images using DSM from LIDAR data. Leica Photogrammetric Suite (LPS) module of Erdsa Imagine 9.2 software was utilized for processing. Several classifications based on supervised maximum likelihood classifier were conducted on the five different datasets. The first classification was performed using the intensity image. The second classification was performed using three digital aerial image channels. The third classification was performed using the three digital aerial image channels and two LIDAR feature images (average and standard deviation). The fourth classification was performed using two LIDAR feature images. The last classification was performed using the three digital aerial image channels combined with intensity metric and two LIDAR feature images (average and standard deviation). Quantitative accuracy assessments of the classification results were performed. A comparison between these five approaches has been carried out. After that morphological operations were performed in order to remove noise. The results revealed that the last approach is the best followed by the third approach then the second approach then the fourth approach followed by the first approach. The last approach result has been improved by applying neural network classification. ENVI 4.8 software was utilized for this purpose. The overall accuracy was 97%, and kappa coefficient was 0.94. It was found that the neural network classification gives better classification accuracy than maximum likelihood classification. The results of the best approach of the maximum likelihood classification (fifth) and the results of the neural network classification were compared with those obtained using only information from the intensity image and showed an increase in accuracy of land-use discrimination up to 35% and 36.7%, respectively.


Title of the Paper: Application of Differential Evolution for Audio Transformers Optimization

Authors: Lukas Kouril, Martin Pospisilik, Milan Adamek, Roman Jasek

Pages: 231-240

Abstract: In audio applications transformers are still employed due to several of their features. They are helpful at noise optimisation in circuits where two blocks are connected, having different output and input impedance. For example, when connecting a low-impedance microphone to an amplifier the input of which is of high impedance, not only the impedances are matched by the transformer, but the voltage gain obtained due to the high turns ratio lets the constructer decrease the gain of the amplifier stage as well, which contributes also to decreasing of the noise. Unfortunately, the design of such transformer is very complex, combining electrical, mechanical and geometrical issues. Therefore the authors of this paper decided to create an algorithm that helps the designer to design the transformer according to the requirements by means of Differential Evolution. The description of this method as well as its results is described in this paper.


Issue 4, Volume 6, 2012


Title of the Paper: Flat Coil Optimizer in the Meaning to Coil Optimization

Authors: Lukas Kouril, Martin Pospisilik, Milan Adamek, Roman Jasek

Pages: 241-248

Abstract: Planar inductors made on a printed circuit board are rather commonly employed today and there are various software applications to help the designers with their proposal. In this paper the authors describe the application called Flat Coil Optimizer developed by them. This application serves for designing proper geometrical dimensions of a single layer spiral coil made on the printed circuit board in order it achieved the desired inductance while its serial resistance is as low as possible. In order to process such optimization, two different approaches have been utilized. Firstly, the optimization can be processed analytically and secondly, Differential evolution can be applied as well. This feature allows the user to decide which method he/she wants to apply and in case of doubts the user can verify the results by employing the other method.


Title of the Paper: Novel Static Ultra Low-Voltage and High Speed CMOS Boolean Gates

Authors: Yngvar Berg, Omid Mirmotahari

Pages: 249-254

Abstract: In this paper we present robust and high performance static ultra low-voltage CMOS binary logic. The delay of the ultra low-voltage logic presented are less than 10% of the delay of standard CMOS inverters. The logic gates presented are designed using semi floating-gate transistors and a current boost technique. The boolean gates resemble domino CMOS. The performance and robustness of different logic gates are examined and compared to complementary and domino CMOS logic.


Title of the Paper: Symmetric Autozeroing Floating-Gate Current Mirror, Differential Pair and Transconductance Amplifier for Ultra Low-Voltage Applications

Authors: Yngvar Berg, Mehdi Azadmehr

Pages: 255-262

Abstract: In this paper we explore the symmetric autozeroing ultra low-voltage current mirror, differential pair and transconductance amplifier and present some applications. The ultralow transconductance amplifier has a current boost function and resembles switch-cap and auto-zero circuits. The current boost technique have been used to implement ultra-low voltage digital logic. The simulated data presented is relevant for a 90nm TSMC CMOS process.


Title of the Paper: Ultra Low-Voltage Differential Static D Flip-Flop for High Speed Digital Applications

Authors: Yngvar Berg

Pages: 263-268

Abstract: In this paper we present an ultra low-voltage and high speed D flip-flop. The flip-flop has an increased current level compared to standard CMOS circuits operating at low supply voltages. The increased current level is obtained by using a synchronized capacitive coupling to a semi floating-gate. The delay of the static differential flip-flop presented is less than 12% compared to conventional differential CMOS flip-flops. The presented circuits have been simulated using Hspice and are valid for 90nm TSMC CMOS process. The proposed high-speed and ultra low-voltage flip-flop can be used for any digital lowvoltage CMOS application.


Title of the Paper: Static Differential Ultra Low-Voltage Domino CMOS logic for High Speed Applications

Authors: Yngvar Berg, Omid Mirmotahari

Pages: 269-274

Abstract: In this paper we present a novel static differential ultra low-voltage (ULV) CMOS logic style for High-Speed applications . The proposed logic style is aimed for high speed serial adders in ultra low-voltage applications. The differential ultra low-voltage inverter presented have less than 10% of the delay than standard CMOS inverters for supply voltages less than 500mV . The simulated data presented is obtained using Hspice simulator and applying a 90nm TSMC CMOS process.


Title of the Paper: Vision Based Hand Gesture Recognition: A Review

Authors: Georgiana Simion Vasile Gui Marius Otesteanu

Pages: 275-282

Abstract: This paper reviews some major trends and the recent evolution in the field of hand gesture recognition. While providing a non-exhaustive inventory of the huge amount of past research in the field, the paper reviews in more detail part based approaches, particularly those embedded in the compositional framework, an emerging dominant trend in computer vision. Several traditional and new applications are also discussed in the paper.


Issue 5, Volume 6, 2012


Title of the Paper: Low Order Model for 2-D Digital IIR Filters

Authors: Lahcene Mitiche, Amel Baha Houda Adamou-Mitiche

Pages: 283-293

Abstract: The work presented in this paper concerns withsynthesis of the two-dimensional Infinite Impulse Response (IIR)filters based on model order reduction. The synthesis is performedwith two methods, the Prony's method (Prony modified) and Iterativemethod, in the spatial domain, and with the method of Semi-Definiteiterative Programming (SDP), in the frequency domain. The orderreduction of the filter is based on the Quasi-Gramians method.


Title of the Paper: Application of Bipolar Operational Amplifiers for Special Measuring Circuits in Electro-Energy

Authors: Jaroslav Lokvenc, Rene Drtina, Josef Sedivy

Pages: 294-304

Abstract: This paper presents new possibilities for the invol-vement of special districts with bipolar operational amplifiers. The proposed circuits are designed primarily for applications in the field of measurement technology heavy current electrical engineering and electrical, for laboratory and process measurement. Although the circuits are designed primarily for basic operating frequency of 50/60 Hz, have a frequency bandwidth wide enough to handle even the signals from the drive. Circuits may be used for measuring and other devices in the processing of low frequency and DC signals and tracking slow processes. The diagrams are applicable to hybrid and mono¬lithic operational amplifier, for special purposes, the precise form can also implement the discrete-based components. The article presents the basic starting points, principles, and equations for these circuits. Application possibilities of these connections are every¬where where it is needed to process and edit analog electrical signal in the higher voltage levels.


Title of the Paper: Invariant Properties of Cascaded Six-Pole Networks

Authors: A. A. Penin

Pages: 305-314

Abstract: The invariant properties of input and output of two-port circuits, established previously, are generalized for a multiport network on the example of six-pole network. The six-pole network is interpreted as two interconnected two-port circuits because of final resistance of the general wire of these circuits. For the preset load conductivities, the projective coordinates of a running regime point are introduced concerning of the characteristic regime points, which set the projective coordinate systems on the input and output of six-pole networks. The invariance or preservation of the projective coordinate in these coordinate systems is shown. The direct and reverse formulas of recalculation of currents and non-uniform coordinates are obtained in the form of fractionally - linear expressions of identical type. The results allow separating or restoring two sensing signals via input currents of the six-pole circuit or the three-wire line inputs without determination of their transmission parameters.


Title of the Paper: Parameter Estimation of Wiener Model using Differential Evolution Algorithm

Authors: Yinggan Tang

Pages: 315-323

Abstract: Wiener model consists of a linear dynamic block followed by a static nonlinear function. This paper presents a novel method for parameter identification of Wiener model using differential evolution algorithm. The linear dynamic block is represented by autoregressive moving average (ARMA) model and the structure of static nonlinear function is assumed to be known in advance. The parameter estimation of Wiener model is converted to a parameter optimization problem. Differential evolution (DE) algorithm is used to search the optimal parameters by minimizing the error between the output of the actual model and that of the identified model. For the convenience of determining the search range of parameters to be estimated, the zeros and poles of linear dynamic block are identified. A new solution representation scheme is proposed for DE algorithm such that it can deal with the case that the linear dynamic block has complex number zeros and poles. The effectiveness of the proposed method is verified through two numerical examples.


Title of the Paper: Detection of Arc Fault on Low Voltage Power Circuits in Time and Frequency Domain Approach

Authors: Shu-Chen Wang, Chi-Jui Wu, Yi-Jie Wang

Pages: 324-331

Abstract: Abstract—For the safe use of electric power, it needs to detect the occurring of electric arc faults on the low voltage power circuits and switch off the power source before the occurring of fires. However, many examples reveal the facts that a number of home fires are caused by electric arc faults. The arc-fault circuit interrupter (AFCI) is a device which can detect the occurring of electric arc in the low voltage circuits, and then it can switch off the power source before the occurring of fire caused by series or parallel electric arc faults. The detection approach is the major part in the design of an AFCI. In the paper, it is to investigate series arc fault detection approach of low-voltage power circuits feeding several characteristics of the load. The test data are collected through the arc fault testing platform. The series arc faults will be verified and evaluated their time-frequency characteristics by using the experimental data and compared with relative literature. By combining the time domain-frequency domain techniques, it sums up six detection rules. Then two detecting methods are developed to suppose detecting approaches. Finally, the experimental data with serial arc faults are used to test the detecting methods and compare with the commercial devices. The purposed detecting methods can effectively detect the occurring of series arc faults, and the probability of malfunction is low.


Title of the Paper: An Optimized High-Impedance Amplifier for Dry-Electrode ECG Recording

Authors: Cedric Assambo, Martin J. Burke

Pages: 332-341

Abstract: This paper presents the design, construction and performance verification of an ultra-low-power amplifier for use in long-term ambulatory recording of the human electrocardiogram (ECG) employing gel-free electrodes. The circuit structure has been optimized to provide the stringent low-frequency response characteristics and common-mode rejection ratio (CMRR) demanded in this application. The amplifier possesses a gain of 40 dB in a 3 dB bandwidth extending from 0.04 Hz to 1250 Hz. It also exhibits a maximum undershoot of 0.09 mV and a maximum recovery slope of 0.04 mVs-1 in response to a short 3mV input pulse of 100 ms duration, which is within the specification limits defined by international standards. The CMRR is greater than 95 dB at a mains frequency of 50 Hz. The amplifier draws a quiescent current of 15 µA from a 3 V battery, resulting in a total power consumption of less than 50 µW. Comparative in-vivo ECG recordings were obtained in several subjects at rest and under exercise conditions. The recordings obtained using the gel-free electrodes prove to be of equal quality to those obtained using traditional self-adhesive, gelled electrodes.


Title of the Paper: The Control System for the Production of Biodiesel

Authors: Stanislav Plsek, Vladimir Vasek

Pages: 342-349

Abstract: This article describes the control unit for the production of biodiesel from waste material, such as fats or oils. The control system is based on programmable logic controller of PCD2 family and provides dosing of feedstock materials (fat or oil) and other material, temperature reactor control, visualization of process and progress of production. It provides easy setting of the parameters of the technological process – transesterification. It was proposed to use in laboratory or small industrial production. There can be connected touch screen terminal to the control unit or the user can use local area network for the connection with computer with web browser to control the production process. The process of desalting is proposing for the preparation of waste materials (fats from leather industry, it’s based on ARM microcontroller from Cortex-M4 family with touch screen LCD (10.4”).


Title of the Paper: Gas Sensors and their Selection

Authors: F. Hruska, S. Plsek

Pages: 350-358

Abstract: Measurement of constitution and feature of gas gives information in content of gas components in mix or in their physical parameters. This measurement is used for environment protection, control of qualities of air in interior, control of quality of combustion at combustion motors and kettles, control and monitoring of chemical processes etc . Measurement has to do with emissions of components of gases at processes and emission, i. e. content of components of mixture of gases. Research results play signification role and development of electrochemical sensors. These elements are realized next to laboratory and industry technical means of measurement and portable equipment of personal protection. There is necessary recognize to study of electrochemical sensors and their application research in detail their principles, positives and negatives of particular methods for determination of concentration of particular gases and is necessary have knowledge in fabrication technique of signals from these sensors.


Title of the Paper: Mathematical and Physical Modelling of the Dynamic Electrical Impedance of a Neuron

Authors: Georgios Giannoukos, Mart Min

Pages: 359-366

Abstract: In this work a mathematical and a physical model of a neuron is put forward using an RLC circuit or operational amplifier circuits. The model can calculate the resistance of a healthy neuron and then by decreasing the value of the resistance we can predict how the neuron will react.


Issue 6, Volume 6, 2012


Title of the Paper: Embedded System for Audio Source Localization based on Beamforming

Authors: Petr Dostalek, Jan Dolinay, Vladimir Vasek

Pages: 367-375

Abstract: Paper presents design of embedded audio sourcelocalization system with respect to compact dimensions, low powerconsumption and easy implementation to applications such asteleconferencing, security and robotics systems. It consists of thethree main functional parts: fixed geometry microphone array withfifteen omnidirectional units with geometrical configuration adaptedfor beamforming at center frequency of 1750 Hz, sixteen channelpreamplifier unit with built-in antialias filter and evaluation unitbased on five 32bit microcontrollers Freescale MCF51AC128 whereeach concurrently processes a part of the localization algorithm.Evaluation unit is equipped with alphanumerical LCD display forvisualization of the device state and localization results inautonomous mode. For communication with supervision system isprovided USB interface allowing complete configuration possibilitiesand results transferring including diagnostic data.


Title of the Paper: Control of Time Delay Systems using Matlab Toolbox

Authors: Marek Dlapa

Pages: 376-384

Abstract: The paper shows an application of Robust ControlToolbox for Time Delay Systems implemented in the Matlab system.The toolbox is used to solve the problem of uncertain time delayusing the D-K iteration and algebraic approach. The algebraicapproach represents a new technique for solving problems arising inthe robust control. It combines the structured singular value,algebraic theory and algorithm of global optimization solvingremaining issues in structured singular value framework. Thealgorithm of global optimization can be alternated with direct searchmethods such as Nelder-Mead simplex method giving solutions forproblems with one local extreme. As a global optimization method,Differential Migration is used, which proved to be reliable in solvingthis type of problems. The D-K iteration represents a standardmethod in the structured singular value theory. The results obtainedfrom the D-K iteration are compared with the algebraic approach.


Title of the Paper: Control of General Time Delay Systems using Matlab Toolbox

Authors: Marek Dlapa

Pages: 385-393

Abstract: The aim of this paper is to show an application ofMatlab toolbox “Robust Control Toolbox for Time Delay Systemswith Time Delay in Numerator and Denominator”. The solvedproblem is robust control of time delay system with time delay innumerator and denominator of the controlled plant. This type ofproblem is usually solved in the ring of retarded quasipolynomial(RQ) meromorphic functions. This approach can solve the task fornominal plants but it is not easy to apply this technique if the planthas uncertain time delays. In this paper, the plant is defined as asystem with uncertain time delays which can vary in predefinedintervals. A method handling this problem in the robust sense isderived and implemented using both the D-K iteration and algebraicapproach. The D-K iteration is a standard method in the structuredsingular value framework. However, some remaining issues arepresent, such as nonzero steady-state error and the necessity ofapproximation of the resulting controller with low order system dueto its high complexity. A solution the algebraic approach combiningthe structured singular value, algebraic theory and globaloptimization method can give. Here, Differential Migration is usedproviding high efficiency in finding the global extreme and reliableresults.


Title of the Paper: Low-Cost Rectifier for Measuring of AC Voltage or Current Frequency Compensation Proposal

Authors: Martin Pospisilik, Pavel Varacha, Milan Adamek

Pages: 394-401

Abstract: Usually the rectifiers are the most problematic devices of the low-cost measurement instruments. The features of a simple full wave rectifier construction with an operational amplifier are usually determined by the rectifying diodes and the slew rate of the operational amplifier and unfortunately, they suffer from the dependence on the amplitude of the measured signal. Of course, special topologies as well as current-mode operating devices can be used, but this paper considers the possibility of how the frequency range of a cheap conventional rectifier can be broadened. It is supposed that the rectifier operates on a single signal level at which it can be well frequency compensated. The measurement is processed indirectly by a microcontroller that changes the amplification factor of a preamplifier in order the target level was achieved. Subsequently the measured value is computed from the amplification factor required to achieve the target level. However, this approach, although it looks simple, can result in very time consuming processing if the frequency of the measured signal is too low. Therefore several approaches and proposals are discussed. The authors believe that the proposed solution, although quite complex, can bring satisfactory results when used in multimeters equipped with a microcontroller that employ a three digit display and are capable of operation up to 100 kHz or 1 MHz in dependence on the construction of its internal circuits.


Title of the Paper: Audio Signal Dynamics Expansion

Authors: Martin Pospisilik, Milan Adamek

Pages: 402-409

Abstract: Currently, audio recordings are usually edited in ordertheir dynamic range was decreased. Such signal processing bringsseveral advantages. When applied, the recordings sound more loudlyeven on cheap and weak reproducing devices. The compressedrecordings act compactly and can also be listened in noisyenvironment. On the other hand, too much compression makes therecording contrived. Therefore the authors of this paper decided tocreate a software-based audio signal dynamics expander and, aftergaining the experience, to discuss further approach to the audio signaldynamics expansion. Both issues are described in this paper.


Title of the Paper: An Approach to the Optimization of the Ackerberg-Mossberg’s Biquad Circuitry

Authors: Martin Pospisilik, Pavel Varacha

Pages: 410-418

Abstract: This paper describes a perspective approach to the electrical circuits design based on the utilization of the evolutionary algorithms. In order to show an example of how the devices of a circuit being described by a mathematical model can be determined, a low pass filter design was chosen, employing the circuitry consisting of two integrators in a feedback loop operating as a filter realizing a general biquadratic function. The modified Ackerber-Mossberg’s topology was used. In the paper not only the results of the optimisation but also the results of simulation of the designed circuits are provided, including the sensitivity analysis.


Title of the Paper: Software Checking of Audio Transformers Manufacturability

Authors: Martin Pospisilik, Milan Adamek

Pages: 419-429

Abstract: Audio transformers seem to be quite omitted in the audio circuits design although they can be useful for their capability of noise and impedance optimization. However it is understandable that the circuit designers try to avoid them for their disadvantages, for example high price, bulky dimensions and complex design, there are still several applications in which the transformers can play important role. Because one of the disadvantages is that for each application there usually occur demands for a specific transformer, that must be designed and manufactured, usually in small series, the authors decided to search for a way how to make the transformer design easier. Therefore in this paper a simple algorithm of checking whether the calculated transformer is manufacturable or not is presented. The algorithm is created in Maple mathematics instrument and provides visualization of the dependences among the particular transformer parameters.


Title of the Paper: Integrating Robots into the Internet of Things

Authors: Cristina Turcu, Cornel Turcu, Vasile Gaitan

Pages: 430-437

Abstract: According to various reports, the number of robots used worldwide is constantly increasing. They are more and more present in different workplaces such as manufacturing, processing operations, dangerous areas, medical environments, military, inaccessible areas etc. Also, robots are able to do social works like assisting people with disabilities or even playing when toys are robotic techniques based. In our days ICT applications became more complex while including various technologies such as wireless communication, wireless or embedded sensor networks, virtual reality, artificial intelligence, cloud computing/storing etc. Due to the new IPV6 protocol every entity in this world could be uniquely identified and be a part of an infrastructure that enables connections between different entities (living or non-living), using different but interoperable communication protocols. Furthermore, everyday entities are becoming either source of information or consumer or both, having communication capabilities and being able to collectively solve complex problems. But, where are the robots? First developed as a tool, nowadays a robot can be integrated as an entity in the new paradigm of Internet of Things (IoT). Thus, in the IoT, a robot can be connected as a thing and establish connections with other things over the Internet. Despite some raised technical issues, the integration of robots within the IoT can offer great advantages in many fields, some of them presented in this paper where aspects related to the technologies involved in the transformation of the robot from a “tool” to a “thing” connected to the Internet of Things are presented.