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Universal Speed and Flux Estimator for Induction Motor

Abstract

In the paper, the concept of universal speed and flux estimator with additional parameters estimators is presented. Proposed solution is based on the Model Reference Adaptive System (MRAS) type flux and speed estimator and can be used in different industrial systems (especially in the automotive applications). Induction Motor (IM) parameters are estimated using the systems based only on simple simulators and adaptive systems (voltage model and current model). Proposed system was tested in the sensorless induction motor drive with the Direct Field Oriented Control (DFOC) algorithm. Simulation and experimental results are presented in the paper.

Open access
Using Push Notification in Telehealth and Remote Patient Monitoring Systems

Abstract

This paper discusses mobile notifications in the context of health monitoring system that measure and store vital signs of the patient that are included in this program. The values measured are temperature and cardiac rhythm. This has two Android application, one is used by the patient to monitor his vital signs and the other is used by the physician to be able to see and receive push notifications of each individual patient. The sensors are connected to a Raspberry Pi and these devices send information to the Android smartphone via Bluetooth. The physician can monitor patient data in real time. All the information that is gathered by the smartphone from the sensors are sent to the cloud, can project a history and can detect some anomalies, for example, if the cardiac pulse is not within the limits of an accepted interval.

Open access
Vertical Transportation: Effects of Harmonics of Drives by PM Machines

Abstract

Permanent magnet motor drive is a widely used technology, offering many advantages, such as exceptional speed, torque control and greater flexibility. Improvement of reliability and efficiency has become a great research interest. Towards this direction and taking into account the major developments in permanent machine technology over the recent years, the use of energy recovery converters has been introduced in various industrial applications. In this paper, the effects of harmonics on a three-phase motor controlled by a drive are analysed, and the behaviours of the filter topology after adopting regenerative drives are studied. The main contribution of this study is a methodology to foresee the standards that can be achieved with the use of an active front end system topology with filters. Moreover, the use of an optimum filter that eases the power system distortion is presented. The analysis presented in this paper is validated experimentally.

Open access
Activity and health monitoring systems

Abstract

This paper presents an Open Platform Activity and health monitoring systems which are also called e-Health systems. These systems measure and store parameters that reflect changes in the human body. Due to continuous monitoring (e.g. in rest state and in physical effort state), a specialist can learn about the individual's physiological parameters. Because the human body is a complex system, the examiner can notice some changes within the body by looking at the physiological parameters. Six different sensors ensure us that the patient's individual parameters are monitored. The main components of the device are: A Raspberry Pi 3 small single-board computer, an e-Health Sensor Platform by Cooking-Hacks, a Raspberry Pi to Arduino Shields Connection Bridge and a 7-inch Raspberry Pi 3 touch screen. The processing unit is the Raspberry Pi 3 board. The Raspbian operating system runs on the Raspberry Pi 3, which provides a solid base for the software. Every examination can be controlled by the touch screen. The measurements can be started with the graphical interface by pressing a button and every measured result can be represented on the GUI’s label or on the graph. The results of every examination can be stored in a database. From that database the specialist can retrieve every personalized data.

Open access
Design of Pyramidal Horn Antenna for 2.45GHz in FEKO for Application in Experimental FSO/RF Hybrid System

Abstract

Communication technologies are growing for day to day because demand on data sharing is unstoppable. Users require availability of approach to network at all time. Implementation of smart technologies allows communication of all type of devices. Capacity of data flow have to grow. Video formats HD or 4K require transmit on high data speed. Based on the demands many types of different communication systems which are suitable for these speeds were designed. One of these systems is FSO (Free Space Optics). FSO system is based on transmission of optical beams which carry the information. This system allow high data speed comparable with standard optical fiber in range to 10km. One of drawbacks of this system is LOS (Light of Sight) between communication points. The other drawback is sensitivity to weather changes. Optical beams interfere with water particles and cause attenuation on transmission path. The solution is in implementation using hybrid FSO/RF system which combines optical communication system with RF (Radio Frequency) backup link. We realized FSO communication link on Technical University of Košice. Our research is focused on design of appropriate type of antenna for our RF backup link. Our results in this area were published.

Open access
Fully Integrated K-Band Active Bandpass Filter In GPDK 90nm CMOS Technology

Abstract

The bandpass filter is one of the essential blocks of every modern RF transceiver. Performance of the transceiver greatly depends on the performance of the bandpass filter. A bandpass filter designed with passive inductors suffers from some drawbacks like large chip size, low-quality factor, less tenability etc. To prevail over these constraints, an active inductor-based bandpass filter circuit has been designed in GPDK-90nm CMOS technology utilizing cadence virtuoso environment. The simulation result shows that the active inductor-based bandpass filter circuit design achieves a gain of 6.79dB, a bandwidth of 5.05 GHz and a noise figure of 3.10dB. The circuit dissipates only 3.55mW power for its operation from a single 1.5V DC supply. By avoiding bulky inductor in the design helped to attain a very small chip area of 127.704μm2.

Open access
An Image Encryption Algorithm with Total Diffusion

Abstract

This paper proposes an image encryption algorithm which uses four scans of an image during the diffusion stage in order to achieve total diffusion between intensities of image pixels. The condition of total diffusion is fulfilled by a suitable combination of techniques of ciphertext chaining and plaintext related diffusion. The proposed encryption algorithm uses two stages which utilize chaotic logistic map for generation of pseudo-random sequences. The paper also briefly analyzes approaches described by other researchers and evaluates experimental results of the proposed solution by means of commonly used measures. Properties of our proposal regarding modifications of plain images prior to encryption or modifications of encrypted images prior to decryption are illustrated by two additional experiments. The obtained numeric results are compared with those achieved by other proposals and briefly discussed.

Open access
New Solar Water Heating System: Safety, Design and Implementation Issues

Abstract

This paper presents a new electronic controller, devoted to solar water heating systems, that implements safety functions to prevent L. pneumophila bacteria outbreaks. The controller uses data retrieved from strategically located probes in order to implement the proposed safety actions. The electronic solution was integrated and validated on a solar system prototype bench that uses real equipment such as collectors, a water storage tank and expansion vessels. Moreover, two particular solar water heating installations were designed devoted to a house family and a nursing home both located on the Mealhada area. The methodology and reported technical solutions in this research could be a practical guide to promote mass market usage of the solar water heating systems in Portugal.

Open access
Personal data acquisition IOT gateway

Abstract

Personal activity tracker are nowadays part of our lives. They silently monitor our movements and can provide valuable information and even important alerts. But usually the user’s data is stored only on the activity tracker device and the processing done is limited by this modest processing power device. Thus it is very important that the user’s data can be stored and processed in the cloud, making the activity tracker an IOT node. This paper proposes a simple IOT gateway solution for a custom user monitoring device.

Open access