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Open access

József Domokos and Zsolt Attila Szakács

Abstract

This paper presents a Romanian language phonetic transcription web service and application built using Java technologies, on the top of the Phonetisaurus G2P, a Word Finite State Transducer (WFST)-driven Grapheme-to-Phoneme Conversion toolkit.

We used NaviRO Romanian language pronunciation dictionary for WFST model training, and MIT Language Modeling (MITLM) toolkit to estimate the needed joint sequence n-gram language model.

Dictionary evaluation tests are also included in the paper.

The service can be accessed for educational, research and other non-commercial usage at http://users.utcluj.ro/~jdomokos/naviro/.

Open access

Katalin György

Abstract

In this brief, I study the finite and infinite nonlinear discrete time optimal control. The quadratic control problem for nonlinear case can be solved with different methods such as: linearization of the system model around each operation point or some different methods, where should be used an on-line parameter identification algorithm. In this paper, I study some properties of these algorithms in order to improve the control efficiency of the nonlinear process control. In this paper, I supposed the all states are accessible, so there is not necessary any state estimation algorithm for the implementation of the proposed optimal control (LQR - Linear Quadratic Regulators) methods.

Open access

Paul Mihăilă, Titus Bălan, Radu Curpen and Florin Sandu

Abstract

Network programmability is a trend, enhanced and inspired by Software Defined Networks, that are based on scripting methods and standard programming languages used for controlling and monitoring of network elements. This paper is illustrating some new methods in configuring network devices by using automation, reducing time for equipment configuration and easier maintenance. It also improves network security by recognizing and fixing security vulnerabilities and it increases the network stability. These methods represent the future of networks, allowing the management of an increased number of devices in a unitary way.

Open access

Tamás Kardos and Dénes Nimród Kutasi

Abstract

Hybrid systems contain both continuous dynamics and discrete elements, where discrete transitions happen between different continuous operating modes as a consequence of certain events. The notion of modeling these types of systems is discussed in regard to the four tank process, which has hybrid and nonlinear characteristics. This paper describes the modeling of this system in Simscape software and a hybrid model is created as well, with a hybrid controller being built around it that includes finite-state automata and PI controller. Simulations implemented in Matlab Simulink software prove the viability and correctitude of the method presented.

Open access

Szabolcs Hajdu, Sándor Tihamér Brassai and Iuliu Szekely

Abstract

This paper presents an FPGA based method for stabilization of a quadcopter around the principal axes pitch, roll, and yaw using IMU sensors for angular estimation and the PID algorithm for control. The goal was to solve the problem in hardware level providing a fast method for stabilization. Using an FPGA circuit parallel with a microprocessor the control of the quadcopter becomes simpler the microprocessor can handle other tasks like area mapping or path calculation parallel with the stabilization hardware implemented on the FPGA. Sensor configuration and calibration was implemented on the FPGA along with the PID controller. The implemented circuit was tested in real time on the quadcopter.

Open access

Margit Antal and András Bandi

Abstract

The widespread use of smartphones and the ability of these devices to digitize signatures have made it possible to sign electronic documents in this way. In this paper we compared two on-line signature databases in terms of verification performance: the MCYT containing signatures drawn by stylus pen, and MOBISIG containing finger drawn signatures. Performance evaluations were performed using both local and global systems. In the case of global systems, we evaluated the performance of a novel information theory features set. Little improvement was achieved by this feature set. There were large differences between the two databases in terms of performance. Finger drawn signatures collected by mobile device were proved inferior to signatures collected by digitizing tablet and its stylus.

Open access

László Bakó, Szabolcs Hajdú and Fearghal Morgan

Abstract

The paper presents three embedded soft-core processor architectures, developed by the authors to be easily implementable while yielding low digital resource usage. These architectures will be compared and contrasted between each-other by introducing a special testing method, based on control algorithm implementations. For reference, the same testing and comparison has been implemented on a well established architecture, too, on the Xilinx PicoBlaze processor. Measurement results and application suggestion are given in the concluding section.

Open access

Antal Fodor

Abstract

Alongside the using of „technical materials’, the direct 3D printed different plastic also speeded up lately. Accordingly to this, it is often designed parts, which have to sustain extreme stress. The proper definition of material qualities is expensive; despite in every phase of designing, we need it to be done perfectly. In every industrial section, it is important to work with exact material characteristics, especially in fields where strict safety rules have to be kept (in connection with the lifespan) the design of fatigue tests of 3D printed polymer specimens. We planned the examinations on the way to avoid the critical temperature range shown by the DMA examinations’ results in the bending point of the inner friction coming up in the local range. This information could be important for the Military to change the busted parts quickly and sound. That is the reason why we designed these examinations in this way, so, it could help for designers in the field of military, in development of security technology and improvement of recovery.

Open access

László-Zsolt Turos, Géza Csernáth and István Hegyi

Abstract

This paper describes a cost effective AC current measurement method that avoids complex AC to DC current measurements by converting an amplified and rectified AC voltage drop across a shunt resistor to a duty cycle of a PWM signal. The current measurement chain output is fed into a microcontroller unit (MCU) and into a short circuit protection block that inhibits AC load drivers in case of overcurrent or short circuit events, overriding the state set by the MCU control algorithm. The authors present a mathematical model, simulations and a practical evaluation of custom-developed circuits that are capable to reach a convincing level of measurement precision. By counting a given number of consecutive AC periods, the effect of inrush current generated by inductive AC loads is filtered. The proposed solution allows inrush currents up to 3A, fitting the consumption range of AC control elements met in household application circuits, such as relays or solenoid valves.

Open access

Ferenc Tolvaly-Rosca and Zoltán Forgó

Abstract

The task of the mixed pure CAD generating method developed by the authors consists in finding only the points situated on the gear tooth surface. The use of the mixed CAD gear generating method results in a very large and particular type of Points Cloud: This contains points situated both in the tooth space, and on the tooth surface. The existing filtering programs and methods, as it was presented in previous papers, cannot deal with these particular point sets. The development of the named particular generating method claims an algorithm and a computer software which can find the envelope of the Points Cloud. This papers presents an Alpha Shape algorithm based filtering algorithm, adapted and developed to be used together with the mixed CAD generating software.