German-Sallo Z.,Petru Maior University of Targu-Mures
IFMBE Proceedings | Year: 2017
HRV signals can be viewed as discrete time series and treated as well through accepted mathematical procedures in order to find specific properties. These mathematical procedures can be linear or non-linear. Lately, non-linear analysis methods brought new and valuable results in HRV analysis and prediction. This paper deals with approximate entropy and sample entropy calculations in order to find unrevealed properties of these signals. The used signals are obtained from the MIT-BIH Long-term ECG database. The aim of this paper is to measure information theory based parameters as different entropies for different signals to emphasize non-linear dynamics in HRV in order to help cardiology specialists. © Springer International Publishing AG 2017.
Szilagyi S.M.,Petru Maior University of Targu-Mures |
Szilagyi L.,Budapest University of Technology and Economics |
Szilagyi L.,Transylvania University
Computers in Biology and Medicine | Year: 2014
TRIBE-MCL is a Markov clustering algorithm that operates on a graph built from pairwise similarity information of the input data. Edge weights stored in the stochastic similarity matrix are alternately fed to the two main operations, inflation and expansion, and are normalized in each main loop to maintain the probabilistic constraint. In this paper we propose an efficient implementation of the TRIBE-MCL clustering algorithm, suitable for fast and accurate grouping of protein sequences. A modified sparse matrix structure is introduced that can efficiently handle most operations of the main loop. Taking advantage of the symmetry of the similarity matrix, a fast matrix squaring formula is also introduced to facilitate the time consuming expansion. The proposed algorithm was tested on protein sequence databases like SCOP95. In terms of efficiency, the proposed solution improves execution speed by two orders of magnitude, compared to recently published efficient solutions, reducing the total runtime well below 1. min in the case of the 11,944. proteins of SCOP95. This improvement in computation time is reached without losing anything from the partition quality. Convergence is generally reached in approximately 50 iterations. The efficient execution enabled us to perform a thorough evaluation of classification results and to formulate recommendations regarding the choice of the algorithm[U+05F3]s parameter values. © 2014 Elsevier Ltd.
Iantovics B.L.,Petru Maior University of Targu-Mures |
Zamfirescu C.-B.,Lucian Blaga University
International Journal of Innovative Computing, Information and Control | Year: 2013
Development of computational systems that intelligently can solve problems represents an important research direction. Many results described in the literature prove, that the intelligence of a computational system can offer advantages in the problems solving versus a system that does not have intelligence. The adaptation is considered to be an important property of many intelligent systems. Sometimes the adaptation is realized by learning. In this paper, we propose a novel adaptive multiagent system called ERMS (Extended Centralized Multiagent System with Cooperative Evolutionary Reorganization Capacity), which uses an evolutionary learning technique in order to improve the efficiency of the undertaken problems-solving. ERMS represents an extension of a previously developed multiagent system called CCER (Centralized Multiagent System with Cooperative Evolutionary Reorganization Capacity). The adaptivity of the ERMS multiagent system, consists in the capacity to reorganize its structure based on the information available about the received problems for solving. The obtained results prove that a multiagent system successfully can use evolutionary algorithms to discover emergent patterns of reorganization for the efficient solving of the undertaken problems. In case of complex systems composed from a large number of interacting components, such emergent behavior of the systems, if have as results improvements (i.e., autonomy, efficiency and exibility) in the problems solving it could be associated with intelligence. © 2013 ICIC International.
Herman E.,Petru Maior University of Targu-Mures
Agricultural Economics (Czech Republic) | Year: 2016
The main objective of the paper is to highlight the impact of agricultural performance on working poverty in the EU countries, in the 2008–2013 period, for identifying some measures that need to be taken to increase the agricultural performance so that the in-work poverty reduces. The comparative analysis shows that agricultural performance, according to the agricultural indicators analysed and the phenomenon of working poverty vary significantly across the EU countries. The correlation and regression analysis results suggest that the high level of employment in agriculture in some EU countries can be mainly explained by the small scale agriculture, a high share of subsistence holdings and a low agricultural labour productivity. The results of the multiple regression analysis highlight that working poverty at the EU level is influenced positively by the employment in agriculture, and is influenced negatively by the economic size farm and land productivity. Moreover, the results show large cross-country differences in terms of agricultural performance-working poverty link, fact which emphasizes the need to take specificactions to improve efficiency of the EU agricultural sector for reducing the working poverty. The findings of the study can be useful for the policymakers to formulate policies for a decent and productive employment within a sustainable development of agriculture. © 2016, Agricultural Economics. All rights reserved.
Katalin A.,Petru Maior University of Targu-Mures
2010 IEEE International Conference on Automation, Quality and Testing, Robotics, AQTR 2010 - Proceedings | Year: 2010
This paper presents a practical power and energy measuring and monitoring system using microcontrollers from the PIC 16Fxxx family, conditioning circuits for current and voltage acquisition and a virtual instrument developed in LabWindows/CVI. The developed system can be used in a singlephase power system, but it can be enlarged very easy for three-phase power system. The conditioning circuits shift the current and voltage signal in the A/D converter signal domain. The microcontroller is responsible for the data acquisition and the communication with the computer. Measured data from the sensors is represented in real time, with the possibility of saving the measured data set for later evaluation. For data representation and harmonic analysis in distorting cases a virtual instrumentation based on LabVIEW was developed. The designed virtual instrument calculates from the acquired data the active and reactive power, the power factor and the frequency and level of the harmonics in case of nonsinusoidal signals.
Dulau L.I.,Petru Maior University of Targu-Mures
Journal of Electrical and Electronics Engineering | Year: 2016
This paper describes the mathematical model for the optimal power flow analysis of the IEEE 14 bus system. In the IEEE 14 bus system were connected two distributed generators (DGs): a hydro generator and a photovoltaic power plant. The two objective functions which are minimized, are the generation costs and the total power losses of the system, while there are satisfied equality and inequality constraints. The optimal power flow analysis will be performed for the steady-state condition of the system and for the whole day, for two cases: the DGs are connected to the system and the DGs are not connected to the system. © 2016, Editura Universitatii din Oradea. All rights reserved.
Szabo Z.K.,Petru Maior University of Targu-Mures |
Herman E.,Petru Maior University of Targu-Mures
Acta Polytechnica Hungarica | Year: 2014
A wide-spectrum of registered entrepreneurial activities can be observed in transition economies. However, the outcomes are not reflected in the projected economic growth. This article examines the entrepreneurial performance of transition economies in the European context and presents a research approach on the relationship between economic development, institutions and entrepreneurship in order to identify needs to eliminate barriers to productive entrepreneurship. The authors present a cluster analysis of EU Member States. In this respect, the scientific approach is a necessity. The findings of the study can be useful for policymakers to formulate policies in concordance with priorities.
Pozdirca A.,Petru Maior University of Targu-Mures
Applied Mechanics and Materials | Year: 2014
The article improves the definition and the technology of the worm called by the author ZPA (a worm generated on NC lathe with standard cylindrical milling tools). First are showed the enveloping calculus for determining the contact line between the tool and the flank of the worm – considering cylindrical generating surfaces. Knowing the contact line, the axial profile can be determined and implicit the flank of worm. Applying some controlled corrections, this worm type can become a standard worm (ZA – for example). This process is assisted by CAD software, developed by the author. The second part approach ZPA worm’s technology: characteristics of the needed NC lathe, processing steps, tools, cutting conditions. The advantages of the ZPA worm type are: the use of standard tools with reduced costs and also short processing time; the possibilities to cover other standard worms, using the standard cylindrical milling tools and non-specialized NC machining tools. © (2014) Trans Tech Publications, Switzerland.
Szilagyi S.M.,Petru Maior University of Targu-Mures
Acta Polytechnica Hungarica | Year: 2015
This paper gives a solution for improving the geometric estimation of the human ventricles, by reducing their shape estimation error. The parametric description of the studied organ can be performed at arbitrary resolution during the whole visualization process. After the problem description, the paper presents each main step of the proposed shape estimation algorithm. The presented method determines not only the general shape of the ventricles, but the internal tissue direction, too. The estimation error decreases more than 10 times if the resolution is increased by 3 times. The biological parameters like gender or age also affect the estimation performance. The obtained accuracy of the method was slightly higher in the case of female hearts and for the left ventricle. Finally, concluding remarks emphasize some important features of the given approach and the future research directions. © 2015, Budapest Tech Polytechnical Institution. All rights reserved.
Agency: European Commission | Branch: FP7 | Program: MC-CIG | Phase: FP7-PEOPLE-2013-CIG | Award Amount: 100.00K | Year: 2014
Modern Networked Critical Infrastructures (NCIs), e.g. the electrical grid, rely on Information and Communication Technologies (ICT) for their operation since ICT can lead to cost reduction as well as greater efficiency, flexibility and interoperability between components. In the past NCIs were isolated environments and used proprietary hardware and protocols, limiting thus the threats that could affect them. Nowadays, with the adoption of Commercial Off-The-Shelf (COTS) ICT, NCIs are exposed to significant cyber threats that can lead to economical and human losses. To address the aforementioned issues, this project aims at elaborating novel holistic methodologies for the design of security and resilience-aware ICT infrastructures for NCIs. The project will develop state-of-the-art techniques and tools to aid engineers in designing secure and resilient industrial ICT-based installations. The novelty of the project consists in the fact that it will fuse together the cyber and physical dimensions of NCI, an important aspect that is missing from existing approaches. The project will create novel NCI network design techniques by solving multi-criteria optimization problems that take into account several aspects such as NCI design standards, e.g. NIST SP 800-82 and NERC CIP 002-009, resilient operation of physical process, but also installation-specific information, e.g. geographical aspects. The project will also provide more effective protection mechanisms, e.g. cyber-physical Intrusion Detection Systems, by combining data from cyber and physical sensors. The proposed research lies in the context of the European Programme for Critical Infrastructure Protection (EPCIP), the Critical Information Infrastructure Protection (CIIP) action plan and the Digital Agenda for Europe (DAE) by addressing key security and resilience issues of NCIs that will ultimately lead to the better protection of existing and future Critical Infrastructures.