AEEE. 2019, vol. 17

Permanent URI for this collectionhttp://hdl.handle.net/10084/134884

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Optical Fiber Tip wth Integrated Mach-Zehnder Interferometer for Sensor Applications
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Gaso, Peter; Jandura, Daniel; Ďurišová, Jana
In this paper, we present design and preparation of novel Mach-Zehnder Interferometer (MZI) based structure for sensing applications. We present integration of this structure at the end of a single-mode optical fiber. Direct laser writing technology was used to prepare MZI-based structure with a hoop for tight connection to optical fiber facet. Details of the design, preparation process and connectorizing process are described and finally, transmission spectral characteristic of the prepared structure was measured using optical spectral analyzer
Sensor Array for Evaluation of Gait Cycle
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Kardoš, Slavomír; Slosarčík, Stanislav; Balog, Peter
The gait motion is an essential part of the life of every human being. The evaluation of human motion is a subject of complex approach and knowledge in the biomechanics area with application in orthopedics, therapy and commercial sporting applications. The monitoring and diagnostics allow determining the background of motion individualities and the defects reasons and impacts. The article describes the possibilities of gait cycle sensing, which has the potential for use in medical diagnostics and rehabilitation process monitoring. The system incorporates a matrix of four FSR (Force Sensing Resistor) pressure sensors and an accelerometric unit for the possibility of posture and step cycle evaluation so that it can be utilizable at diagnostic or rehabilitation during gait cycle retraining or sporting activities monitoring
An Unbalanced Clock Based Dynamic Comparator: A High-Speed Low-Offset Design Approach for ADC Applications
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Varshney, Vikrant; Nagaria, Rajendra Kumar
Currently, dynamic comparator approach necessitates in high-speed and power eÿcient analog-to-digital converter applications due to its high latching speed and ultra-low power consumption. In this paper, a novel dynamic comparator is proposed to reduce latch delay and offset. The comparator benefits from add-on cross-coupled transistors in latch structure and unbalanced clocks to enhance comparison speed and to lessen input offset voltage occurred due to mismatch in cross-coupled circuits in latch stage. The derivations for delay and input offset voltage are presented for proposed dynamic comparator with meticulous Monte-Carlo simulations. The results are verified by simulations in CADENCE SPECTRE at 1 V supply voltage and 90 nm CMOS technology. A comparative analysis between the proposed dynamic comparator and the previous reported comparators has been presented. It is observed that the delay is reduced up to 46 % and 6 % as compared to conventional and two phase dynamic comparator, respectively. Moreover, the proposed design consumes 53.36 µW power only. The Monte-Carlo simulation shows that the standard deviation of input offset voltage is 10.8 mV which is 12 % and 77 % of conventional and two phase dynamic comparator, respectively
Linking Bitstream Information to QoE: A Study on Still Images Using HEVC Intra Coding
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Miždoš, Tomáš; Barkowsky, Marcus; Uhrina, Miroslav; Počta, Peter
The coding tools used in image and video encoders aim at high perceptual quality for low bi-trates. Analyzing the results of the encoders in terms of quantization parameter, image partitioning, prediction modes or residuals may provide important insight into the link between those tools and the human perception. As a first step, this contribution analyzes the possibility to transcode reference images of three well-known image databases, i.e. IRCCyN/IVC, LIVE and TID2013, from their original, older formats to HEVC; thus creating a homogeneous database of 327 HEVC encoded images accompanied with bitstream parameters and values obtained from objective and subjective as-sessments. Secondly, it analyzes some of the HEVC intra coding parameters regarding their influence on the image quality by using machine learning, namely Support Vector Machine - Regression
Performance Analysis of MIMO Wavelet Packet Multicarrier Multicode CDMA System with Antenna Selection
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Akho-Zahieh, Maryam Mahmoud; Abdellatif, Nasser
Performance of Multicarrier Multicode Code-Division Multiple Access (MC/MCD-CDMA) systems can be improved significantly by using Wavelet Packets (WPs) as subcarriers instead of a sinusoidal function. This is because WPs have much lower side-lobes and negligible sidelobe energy leakage compared to sinusoidal carriers; this property significantly decreases the intercarrier interference and improves the system performance. Further improvement can be achieved by utilizing multiple antennas at transmitter and receiver to construct a Multiple-Input Multiple-Output (MIMO) system. Channel hardening is the main drawback of MIMO systems. Antenna selection can be employed to reduce this problem. In this paper, we use the an-tenna selection in MIMO WP-MC/MCD-CDMA sys-tem. These combinations of antenna selection, MIMO, and WP in MC/MCD-CDMA improve the system per-formance significantly and reduce the channel harden-ing. The performance of the system is tested accord-ing to the outage probability and bit error rate. Two MIMO schemes on Nakagamim fading channel are considered, which are: selective transmit /selective re-ceive and selective transmit /maximum ratio combining receive. The study includes the effects antennas’ number, fading parameter-m, number of users, and the threshold signal to interferences plus noise ratio. The performance of the system is compared to that of MC/MCD-CDMA based on a sinusoidal carrier. The results reveal that: by increasing antennas’ number, the system performance is improved significantly, and MC/MCD-CDMA system based on WPs carriers out-performs MC/MCD-CDMA system based on a sinusoidal carrier
Introduction to the Computation Offloading from Mobile Devices to the Edge of Mobile Network
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Doležal, Jakub; Zeman, Tomáš
This paper introduces the concept of Small Cell Cloud (SCC) composed of multiple Cloud-enabled Small Cells (CeSCs), which provide radio connection for mobile User Equipment (UE) such as smart-phones or wearables such as smart glasses. Moreover, CeSCs host computations offloaded from UEs in a way similar to centralized cloud, yet different in its proximity to users. Proposed client-server architecture of SCC con-veys mechanisms for moving offloaded computations from the UEs to CeSCs. Real-life implementation of the SCC architecture relies on custom-developed Of-floading Framework which is responsible for low-level communication between the UE and the SCC. The Of-floading Framework is accompanied by an Augmented Reality (AR) app, which employs intensive computa-tions for discovery of places of interest. Such app is latency-sensitive, a criterion which makes computation offloading beneficial due to its ability to decrease la-tency. The combination of the O˜oading Framework and the AR app makes up an SCC testbed used for fur-ther performance evaluation. Numerous measurements are carried out to examine the impact of various pa-rameters. Based on Proof-of-concept implementation and thorough measurements, it has been revealed that computation offloading can decrease overall latency as much as to 47 % and energy consumption on the UE side to 56 %
Simplified Second-Order Generalized Integrator - Frequency-Locked Loop
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Ahmed, Hafiz; Benbouzid, Mohamed El Hachemi
Second-Order Generalized Integrator –Frequency-Locked Loop (SOGI-FLL) is a popular technique available in the grid synchronization literature. This technique uses gain normalization in the frequency locked-loop. This increases the computational complex-ity. In this paper, we propose an alternative imple-mentation to reduce the computational complexity of the SOGI-FLL. The proposed implementation modifies mainly the frequency locked-loop part and requires normalized voltage measurement. dSPACE 1104 board-based hardware implementation shows that the proposed implementation executes 20 % faster than the standard implementation. This could be very beneficial for high switching frequency application e.g. ≥ 1 MHz. In ad-dition to the nominal frequency case, multiresonant implementation is also proposed to tackle grid harmonics using a simpler harmonic decoupling network. Small signal dynamical modeling and tuning are performed for both implementations. Dynamical equivalence is also established between the two implementations. Experimental comparative analysis demonstrates similar or better performance (depending on test scenarios) with respect to the standard implementation of the SOGI-FLL
Shoot-Through Control-Based Space Vector Modulation Approach for a Modified Z-Source NPC Power Inverter
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Noui, Samir; Tabbache, Bekheira; Hadjou, Farid; Berkouk, El-Madjid; Zhou, Zhibin; Benbouzid, Mohamed El Hachemi
Z-source Neutral Point Clamped (NPC) in-verter is a converter topology that combines the benefits of both the impedance network by storing temporary energy released to the load for voltage boosting and NPC inverter by guaranteeing lower Total Harmonic Distor-tions (THDs) and reducing voltage stresses of switching devices. In this context, this paper deals with a modified three-level Z-source NPC inverter topology with simplified command to generate shoot-through states and reduce switching losses. For this reason, an extra power switch Insulated Gate Bipolar Transistor (IGBT) is added to insert shoot-through, thus eliminating the need for full-shoot-through on any of the three branches of the inverter. On the other hand, a modified Space Vec-tor Modulation (SVM) strategy is proposed. This gives a number of benefits, both in terms of implementation and harmonic performance. Effectiveness of the proposed topology is verified through simulations using Matlab toolbox Simulation and laboratory experiment
Performance Evaluation of Three-Leg Voltage Source Inverter Fed Unsymmetrical Two-Phase Induction Motor Based on Genetic Algorithm for Parameter Estimation
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Kongsuk, Prayad; Kinnares, Vijit; Phumiphak, Phunyaphat
This paper presents an evaluation method of performance characteristics in terms of loss, currents and electromagnetic torque of an unsymmetrical two-phase induction motor driven by a three-leg Voltage Source Inverter (VSI) providing unbalanced two-phase voltages. The model parameters for consideration of loss and dynamic performance of the motor are estimated by using Genetic Algorithm (GA). Also, syn-thesized winding current waveforms based on a super-position method and frequency domain of known har-monic voltages are investigated. The methodology of the proposed GA applied to parameter estimation of the unsymmetrical two-phase induction motor is fully given. Carrier-based unbalanced Space Vector Pulse With Modulation (SVPWM) is employed and imple-mented on a low-cost microcontroller. In order to prove the validity of the model with the parameters obtained by GA, performance comparison with the experiment and the model with the parameters obtained by conventional test in laboratory has been made. The results of simulation with the proposed parameters and experiment are in good agreement
Photolithographic Mask Fabrication Process Using Cr/Sapphire Carriers
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Zawadzka, Agnieszka; Prażmowska, Joanna; Paszkiewicz, Regina
Elaboration of the technology of novel photolithographic masks fabricated on sapphire substrates for UV and DUV application was described. The main technological steps of mask fabrication as Cr metallization deposition, selection of resist for lithography and Cr layer etching were developed and reported. The etching of Cr films was carried out through resist mask. Detailed study of Cr layer etching process was performed using different solutions such as KMnO4, HCl and ceric ammonium nitrate-based solutions to obtain good-quality structures with the smallest possible undercut of Cr layer and smooth edge. The mask fabrication process was validated by fabrication of test structures of microelectronic device using photolithography technique.
Diffraction Properties and Application of 3D Polymer Woodpile Photonic Crystal Structure
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Urbancová, Petra; Pudiš, Dušan; Goraus, Matej; Šušlík, Ľuboš; Sciana, Beata; Dawidowski, Wojciech; Kováč, Jaroslav; Skriniarová, Jaroslava
We present a new technique for modification of diffraction and optical properties of photonic devices by surface application of polymer Three-Dimensional (3D) woodpile Photonic Crystal (PhC) structure. Woodpile structure based on IP-Dip polymer was designed and fabricated by Direct Laser Writing (DLW) lithography method based on nonlinear Two-Photon Absorption (TPA). At first, we investigated diffraction properties of woodpile structure with a period of 2 μm. The structure was placed on a glass substrate, and diffraction patterns were measured using laser sources with different wavelengths. After diffraction properties investigation, the fabricated structures were used in optoelectronic devices by their surface application. Our polymer 3D PhC woodpile structures were used for radiation properties modification of light emitting devices - optical fiber and Light Emitting Diode (LED) and for angular photoresponse modification of InGaAsN-based photodiode. The modification of the far-field radiation patterns of optical fiber and LED and spatial modulation of light coupling into photodiode chip with applied structures were measured by goniophotometer. Quality of fabricated structures was analyzed by a Scanning Electron Microscope (SEM).
High Load-Induced Birefringence of PMMA Investigated in VIS/NIR Spectral Range
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Tarjányi, Norbert; Uhričík, Milan; Káčik, Daniel; Palček, Peter
In the paper, we present the results of an investigation of polymethylmetacrylate’s birefringence induced due to applying high-load. The stress-induced birefringence of the polymethylmetacrylate samples was experimentally investigated by an apparatus combining an in-house made plane polariscope with a machine for fatigue testing of materials. A halogen lamp was used as the source of white light. The polariscope’s basis was formed by two sets of plane polarizers, one designed for visible (470-750) nm and another one for near-infrared (900-1800) nm spectral range, respectively. The investigated sample was placed between the polarizers and light that passed through the polariscope was collected by an optical fiber connected to an appropriate optical spectral analyzer. The spectra of transmitted light were measured as a function of load and their analysis provided information on the load-induced birefringence of the investigated polymethylmetacrylate samples.
Taylor Series Based Integration in Electric Circuits Simulations
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Šátek, Václav; Veigend, Petr; Nečasová, Gabriela
This paper deals with the extremely precise, stable and fast solution of the ordinary differential equations. The solution of these is performed using a method based on the Taylor series - The Modern Taylor Series Method. The paper investigates two problems to demonstrate the positive properties of the method: linear problem - the behavior of signal transmission on the telegraph line and a non-linear problem - the Van der Pol oscillator. Both problems were analyzed and solved using newly implemented MATLAB Modern Taylor Series Method solvers. The results were then compared to the state-of-the-art MATLAB solvers.
Secure and Robust Image Watermarking Scheme Using Homomorphic Transform, SVD and Arnold Transform in RDWT Domain
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Khare, Priyank; Srivastava, Vinay Kumar
The main objective for a watermarking technique is to attain imperceptibility, robustness and security against various malicious attacks applied by illicit users. To fulfil these basic requirements for a scheme is a big issue of concern. So, in this paper, a new image watermarking method is proposed which utilizes properties of homomorphic transform, Redundant Discrete Wavelet Transform (RDWT), Arnold Transform (AT) along with Singular Value Decomposition (SVD) to attain these required properties. RDWT is performed on host image to achieve LL subband. This LL subband image is further decomposed into illumination and reflectance components by homomorphic transform. In order to strengthen security of proposed scheme, AT is used to scramble watermark. This scrambled watermark is embedded with Singular Values (SVs) of reflectance component which are obtained by applying SVD to it. Since reflectance component contains important features of image, therefore, embedding of watermark in this part provides excellent imperceptibility. Proposed scheme is comprehensively examined against different attacks like scaling, shearing etc. for its robustness. Comparative study with other prevailing algorithms clearly reveals superiority of proposed scheme in terms of robustness and imperceptibility.
On registration of vector maps with known correspondences
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Jelínek, Aleš; Ligocki, Adam
Data association and registration is an important and actively researched topic in robotics. This paper deals with registration of two sets of line segments, which is especially useful in mapping applications. Our method is non-iterative, finding an optimal transformation in a single step, in a time proportional only to a number of the corresponding line segments. The procedure also provides diagnostic measures of reliability of the computation and of similarity of the data sets being registered. At this point, the method presumes known correspondences, which is limiting, but the discussion, in the end, reveals some possibilities to overcome this issue. Practical properties are demonstrated on a typical task of localization of a robot with a known map.
Advanced Wireless Sensors Used to Monitor the Impact of Environment Design on Human Physiology
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Vavrinský, Erik; Kotradyová, Veronika; Svobodová, Helena; Kopani, Martin; Donoval, Martin; Sedlák, Samuel; Subjak, Ján; Závodník, Tomáš
This article describes modern wireless sensor devices and their application in the measurements of the human physiology. We used our own advanced ECG Holter device and EEG helmet to record the heart and brain activity impacted by different environments, materials, colors or body positions during work. In this paper, we want to show the interactions between humans and architecture design, which modify human work performance and well-being. This paper is a conclusion of the 3 different pilot studies, where different scopes of human-space interaction were explored. In the experiments, we aimed mostly at wood materials and their beneficial effects on the nervous system. The research in its actual state is primarily focused on optimizing the methods of the ECG data analysis from our Holter device and the EEG data from helmet. Based on these data, we will improve the methodology of the experiments for the next enhanced research with aspiration to automate data analysis.
Wavelet-Based Kernel Construction for Heart Disease Classification
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Nguyen, Thanh Hai,; Nguyen, Nghia Thanh; Nguyen, Manh Hung; Livatino, Salvatore
Heart disease classification plays an important role in clinical diagnoses. The performance improvement of an Electrocardiogram classifier is therefore of great relevance, but it is a challenging task too. This paper proposes a novel classification algorithm using the kernel method. A kernel is constructed based on wavelet coefficients of heartbeat signals for a classifier with high performance. In particular, a wavelet packet decomposition algorithm is applied to heartbeat signals to obtain the Approximation and Detail coefficients, which are used to calculate the parameters of the kernel. A principal component analysis algorithm with the wavelet-based kernel is employed to choose the main features of the heartbeat signals for the input of the classifier. In addition, a neural network with three hidden layers in the classifier is utilized for classifying five types of heart disease. The electrocardiogram signals in nine patients obtained from the MIT-BIH database are used to test the proposed classifier. In order to evaluate the performance of the classifier, a multi-class confusion matrix is applied to produce the performance indexes, including the Accuracy, Recall, Precision, and F1 score. The experimental results show that the proposed method gives good results for the classification of the five mentioned types of heart disease.
Novel Ternary Logic Gates Design in Nanoelectronics
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Etezadi, Sajjad; Hosseini, Seied Ali
In this paper, standard ternary logic gates are initially designed to considerably reduce static power consumption. This study proposes novel ternary gates based on two supply voltages in which the direct current is eliminated and the leakage current is reduced considerably. In addition, ST-OR and ST-AND are generated directly instead of ST-NAND and ST-NOR. The proposed gates have a high noise margin near V_(DD)/4. The simulation results indicated that the power consumption and PDP underwent a~sharp decrease and noise margin showed a considerable increase in comparison to both one supply and two supply based designs in previous works. PDP is improved in the proposed OR, as compared to one supply and two supply based previous works about 83% and 63%, respectively. Also, a memory cell is designed using the proposed STI logic gate, which has a considerably lower static power to store logic ‘1’ and the static noise margin, as compared to other designs.
Cross-Coupled Charge Pump Synthesis Based on Full Transistor-Level
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Marek, Jan; Hospodka, Jiří; Šubrt, Ondřej
This paper presents utility for the design of the cross-coupled charge pump, which is used for supplying peripherals with low current consumption on the chip, as the EEPROM or FLASH memories. The article summarizes the knowledge in the field of the theoretical and practical analysis of the cross-coupled charge pump (design relationships and their connection with the pump parameters, as the threshold voltage, power supply voltage, clock signal frequency, etc.) that are applicated in the design algorithm. Optimal MOSFETs sizes (W, L) were find based on the construct of the time response characteristics of the pump sub-block and finding of the maximal voltage increase in the active interval of the clock signal and minimizing of the pump losses, as the switch reverse current, inverter cross current, etc. Synthesis process includes the design of the pump functional blocks with dominant real properties, which are described based on BSIM equations for long channel MOSFET. The pump stage complex model is applicated for estimation of the number of pump stages via state-space model description and using of the interpolation polynomial functions in the algorithm. It involves the construction of the time response characteristic due to the state variables and prediction of the number of the pump stages for the next cycle based on the previous data. Optimization of the pump area is based on the minimizing of the main capacitor in each of the pump stages (number of the pump stages must be increased to obtain the desired output voltage value.) Access is designed to stress the maximum pump voltage efficiency. The whole procedure is summarized in the practical example, in which the solution is shown both in terms of maximal voltage efficiency and the optimal pump area on a chip with respect to the clock signal frequency. Added functions of the design environment are explained, inclusive of the designed pump netlist generating for professional design environment Mentor Graphics including the real models of components that are available in library MGC Design Kit. The procedure gives designer credible results without long timeconsuming optimization process. In addition, the complex model allows the inclusion effects of higher-levels.
Experimental Validation of an Integral Sliding Mode-Based LQG for the Pitch Control of a UAV-mimicking Platform
(Vysoká škola báňská - Technická univerzita Ostrava, 2019) Khan, Said; Bendoukha, Samir; Naeem, Wasif; Iqbal, Jamshed
In this paper, an enhanced Integral Sliding Mode-based Linear Quadratic Gaussian (ISM-LQG) controller has been proposed and verified in real-time on a Twin Rotor multi-input-multi-output MIMO System (TRMS). A TRMS serves as a suitable laboratory-based platform to evaluate the performance of control algorithms for complex Unmanned Aerial Vehicle (UAV) systems such as rotocraft. In the proposed scheme, an ISM enhancement to an LQG has been introduced, which attempts to overcome modelling inaccuracies and uncertainties. The novelty of the proposed control law lies in hybridizing a robust control approach with an optimal control law to achieve improved performance. Experimental results on the TRMS demonstrate that the ISM-LQG strategy significantly improves the tracking performance of the TRMS pitch and hence confirm the applicability and efficiency of the proposed scheme.

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