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A probabilistic demand side management approach by consumption admission control [article]

Lorant Kovacs, Rajmund Drenyovszki, Andras Olah, Janos Levendovszky, Kalman Tornai, Istvan Pinter
2016 arXiv   pre-print
New generation electricity network called Smart Grid is a recently conceived vision for a cleaner, more efficient and cheaper electricity system. One of the major challenges of electricity network is that generation and consumption should be balanced at every moment. This paper introduces a new concept for controlling the demand side by the means of automatically enabling/disabling electric appliances to make sure that the demand is in match with the available supplies, based on the statistical
more » ... characterization of the need. In our new approach instead of using hard limits we estimate the tail probability of the demand distribution and control system by using the principles and the results of statistical resource management.
arXiv:1608.00546v1 fatcat:cvqvgy6iofb3hcohp4nofr4c3e

Quadratic Programming for TDMA Scheduling in Wireless Sensor Networks

Gergely Treplán, Kálmán Tornai, János Levendovszky
2011 International Journal of Distributed Sensor Networks  
This paper presents a novel Multihop Aperiodic Scheduling (MAS) algorithm which guarantees energy-efficient data collection by Wireless Sensor Networks (WSNs) under delay constraints. Present Medium Access Control (MAC) protocols in WSNs typically sacrifice packet latency and/or the reliability of packet transfer to achieve energy-efficiency. Thus, the paper is concerned with developing a novel protocol to achieve energy efficient and reliable multihop data transfer in WSNs satisfying given
more » ... ncy requirements. Energy efficiency is achieved by optimizing the scheduling of the underlying Time Division Multiple Access (TDMA) system by minimizing the wake-up number of the nodes. Schedule optimization is transformed into a quadratic programming (QP) task, which is then solved by the Hopfield net in polynomial time. In this way, an energy efficient scheduling can be obtained which meets a given delay requirement in TDMA systems. The performance of the new algorithm has been evaluated by simulations and compared to the performance of well-known scheduling methods, such as SMAC, UxDMA (a slot assignment algorithm for WSN), and traditional tree-based protocols. The simulations have demonstrated that our method reduces global power consumption for time-driven monitoring.
doi:10.1155/2011/107062 fatcat:uq2cjihkjveffmwq7zuqglhcwm

Improvements to the Hopfield Neural Network Solution of the TWT Scheduling Problem

Kálmán Tornai, Norbert Fogarasi, János Levendovszky
2013 Periodica Polytechnica Electrical Engineering  
This paper explores novel, polynomial time, heuristic, approximate solutions to the NP-hard problem of finding the optimal job schedule on identical machines which minimizes total weighted tardiness (TWT). We map the TWT problem to quadratic optimization and demonstrate that the Hopfield Neural Network (HNN) can successfully solve it. Furthermore, the solution can be significantly sped up by choosing the initial state of the HNN as the result of a known simple heuristic, we call this Smart
more » ... eld Neural Network (SHNN). We also demonstrate, through extensive simulations, that by considering random perturbations to the Largest Weighted Process First (LWPF) and SHNN methods, we can introduce further improvements to the quality of the solution, we call the latter Perturbed Smart Hopfield Neural Network (PSHNN). Finally, we argue that due to parallelization techniques, such as the use of GPGPU, the additional cost of these improvements is small. Numerical simulations demonstrate that PSHNN outperforms HNN in over 99% of all randomly generated cases by an average of 3-7%, depending on the problem size. On a specific, large scale scheduling problem arising in computational finance at Morgan Stanley, one of the largest financial institutions in the world, PSHNN produced a 5% improvement over the next best heuristic.
doi:10.3311/ppee.2090 fatcat:bq3atf7tlrds7e7mbvp3ox6rw4

Bottom-up modeling of domestic appliances with Markov chains and semi-Markov processes

Rajmund Drenyovszki, Lóránt Kovács, Kálmán Tornai, András Oláh, István Pintér
2018 Kybernetika (Praha)  
Kalman filter realization of Bayesian Filtering is applied for learning the probability of time and extent of use of arbitrary appliances from metering data.  ... 
doi:10.14736/kyb-2017-6-1100 fatcat:dxxrqd23bffclovqoohozgosq4

Novel Load Balancing Algorithms Ensuring Uniform Packet Loss Probabilities for WSN

Janos Levendovszky, Kalman Tornai, Gergely Treplan, Andras Olah
2011 2011 IEEE 73rd Vehicular Technology Conference (VTC Spring)  
In this paper, we develop optimal scheduling mechanisms for packet forwarding in Wireless Sensor Network, where clusterheads are gathering information with a predefined Quality of Service. The objective is to ensure balanced energy consumption and to minimize the packet loss probability, subject to time constraints (i.e. different nodes must send all their packets within a given time interval). Novel solutions of scheduling are developed by combinatorial optimization, and by quadratic
more » ... g methods. In our approach, the scheduling of packet forwarding is broken down to a discrete quadratic optimization problem and the optimum is sought by a Hopfield Neural Network yielding the solution in polynomial time. The scheduling provided by the Hopfield Neural Network indeed guarantees uniform packet loss probabilities for all the nodes and saves the energy of the clusterheads. In this way, the longevity of the network can be increased. Index Terms-scheduling, wireless sensor networks (WSN), quadratic optimization, Hopfield Neural Networks (HNN)
doi:10.1109/vetecs.2011.5956703 dblp:conf/vtc/LevendovszkyTTO11 fatcat:c3eksrjx4ve7znh367kx3fop3y

Microsimulation based quantitative analysis of COVID-19 management strategies [article]

Istvan Z Reguly, David Csercsik, Janos Juhasz, Kalman Tornai, Zsofia Bujtar, Gergely Horvath, Bence Keomley-Horvath, Tamas Kos, Gyorgy Cserey, Kristof Ivan, Sandor Pongor, Gabor Szederkenyi (+2 others)
2021 medRxiv   pre-print
Pandemic management includes a variety of control measures, such as social distancing, testing/quarantining and vaccination applied to a population where the virus is circulating. The COVID 19 (SARS-CoV-2) pandemic is mitigated by several non-pharmaceutical interventions, but it is hard to predict which of these regulations are the most effective for a given population. Methods We developed a computationally effective and scalable, agent-based microsimulation framework. This unified framework
more » ... s fitted to realistic data to enable us to test control measures (closures, quarantining, testing, vaccination) in multiple infection waves caused by the spread of a new virus variant in a city-sized societal environment. Our framework is capable of simulating nine billion agent steps per minute, allowing us to model interactions in populations with up to 90 million individuals. Findings We show that vaccination strategies prioritising occupational risk groups minimise the number of infections but allow higher mortality while prioritising vulnerable groups minimises mortality but implies increased infection rate. We also found that intensive vaccination and non-pharmaceutical interventions can substantially suppress the spread of the virus, while low levels of vaccination and premature reopening may easily revert the epidemic to an uncontrolled state. Interpretation Our analysis highlights that while vaccination protects the elderly from COVID-19, a large percentage of children will contract and spread the virus, and we also show the benefits and limitations of various quarantine and testing scenarios. Funding This work was carried out within the framework of the Hungarian National Development, Research, and Innovation (NKFIH) Fund 2020-2.1.1-ED-2020-00003.
doi:10.1101/2021.06.20.21259214 fatcat:nzuph7xvpfe77ccghj6egblmi4

Microsimulation based quantitative analysis of COVID-19 management strategies

István Z. Reguly, Dávid Csercsik, János Juhász, Kálmán Tornai, Zsófia Bujtár, Gergely Horváth, Bence Keömley-Horváth, Tamás Kós, György Cserey, Kristóf Iván, Sándor Pongor, Gábor Szederkényi (+3 others)
2022 PLoS Computational Biology  
Data curation: Ja ´nos Juha ´sz, Ka ´lma ´n Tornai, Zso ´fia Bujta ´r, Gergely Horva ´th, Tama ´s Ko ´s. Methodology: Ja ´nos Juha ´sz, Ka ´lma ´n Tornai.  ...  Validation: Ja ´nos Juha ´sz, Ka ´lma ´n Tornai, Zso ´fia Bujta ´r, Tama ´s Ko ´s. Visualization: Istva ´n Z. Reguly, Ka ´lma ´n Tornai, Gergely Horva ´th. Writing -original draft: Istva ´n Z.  ... 
doi:10.1371/journal.pcbi.1009693 pmid:34982766 pmcid:PMC8759654 fatcat:gqrffao2lrdzbljcnp4ngninay


Phd Disszertáció, Tornai Kálmán
HATÉKONY MONITOROZÁS ÉS ERŐFORRÁS-GAZDÁLKODÁS ÉRZÉKELŐ HÁLÓZATOKKAL Tornai Kálmán KIVONAT Számos olyan alkalmazás jelent meg a kommunikációs-és szenzoros technológia fejlődésének köszönhetően, amely  ... 

Novel Load Balancing Scheduling Algorithms for Wireless Sensor Networks

Endre László, Kálmán Tornai, Gergely Treplán, János Levendovszky
In this paper, optimal scheduling mechanisms are developed for packet forwarding in wireless sensor networks, where clusterheads are gathering information. The objective is to monitor real-life processes for a given time interval and forward packets with minimum loss probabilities to the base station. In order to achieve this objective we develop an optimal scheduling algorithm, which determines the time slots in which packets must be sent by the nodes. The scheduling algorithm, on the one
more » ... guarantees that all the packets will be sent within a predefined time window and thus meeting delay constraints and, on the other hand, it provides uniform packet loss probabilities for all the nodes. The algorithm we propose is capable of providing optimal scheduling with given constraints and guarantees balanced load in polynomial time.

Automated Categorization of Consumers Based on Consumption Forecast in Smart Grid

Kálmán Tornai, András Oláh
Deploying smart meters in Smart Grid systems entails that large amount of measurement data is acquired. By processing and analyzing the data, relevant information can be obtained about the power consumers. One of the most important tasks is determining the main characteristics of the consumer in order to find the best suitable category. This categorization may be essential i) to optimize and estimate the load of transportation grid; ii) to provide the best rate for the consumer as well as the
more » ... pplier in case of free market of electricity; iii) to forecast and to plan correctly the required amount of energy from power-plants to minimize the difference between the demand and supply. In this paper, a categorization method based on forecasting consumption time series will be introduced to categorize consumers with different consumption patterns with good performance. The performance of the method was subject of analysis, and the new algorithm is proved to be usable in real applications.

نظرية ليفي بن جرشوم في خلود النفس واصولها الرشدية

اشرف منصور
2012 مجلة کلية الآداب . جامعة الإسکندرية  
 -sur-Ceze Languedoc Stephen Chak Tornay: "Averroes's Doctrine of the Mind".  ...  Kalman P. Bland, The Epistle on the Possibility of Conjunction by Ibn Rushd (With the Commentary of Moses Narboni).  ... 
doi:10.21608/bfalex.2012.153392 fatcat:mjb5r2qnubfb5jfz6xn2kakcfq

La littérature hongroise en komi

Nikolaj Rakin
2018 Études finno-ougriennes  
А modell) ; • Kálmán Mikszáth, « Le paysan qui a acheté une faux » (Kom. Коса ньöбысь крестьянин ; Hong. A kaszát vásárló paraszt) ; • Zsigmond Móricz, « Les barbares » (Kom. Немортъяс ; Hong.  ...  Льöм ю (« Rivière de merises », 2008), où ont été intégrées les traductions susnommées de Petőfi, Vajda, Garai, Buda ainsi que la traduction de l'hymne hongrois et des poèmes de József Szervác, József Tornai  ... 
doi:10.4000/efo.9546 fatcat:omgc32tchrcdhpa5pbfjca7q2y

Contents of volume 153, 2012

2013 Orvosi Hetilap  
., Tornai, I., Újhelyi, E., Hunyady, B. : Hungarian consensus guideline for the diagnosis and treatment of B, C, and D viral hepatitis. 375 Malina, T., Babocsay, G., Krecsák, L., Schuller, P., Zacher,  ...  mammográfia 3 marfan-szindróma 296 markusovszky-emlékülés 834 meddőség, férfi 1787 médiademokrácia 821 méhnyak adenoid cysticus carcinoma terhesség 1207 kührner éva dr. 154-H termékenység, iBD 1855 kürti kálmán  ... 
doi:10.1556/oh.2013.29592 fatcat:kprhdala7fadbbqfxazea7n4ue

Adalékok a 19. századi magyar festészet orientalista vonatkozásaihoz

Ágnes Mészáros, Gabriella Szvoboda Dománszky
bizonyítékok felvonultatásával bizonygatta a magyar nemesi eredetet." 22 Az osztrák szakirodalom az orientalista festészet osztrák iskoláját reprezentáló művészek csoportjába Ligeti Antalt, Eisenhut Ferencet, Tornai  ...  Kurátor: Elena Olariu. 651 OMKT 1904, OMKT 1909, Tornai 1917, Tornai 1929. 652 Kálmán 2007. 653 Kálmán 2007, 14., 18. 654 Magyar Királyi festészeti mesteriskola anyakönyve 1883-18.., I. és II. kötete.  ...  Idézi Kálmán 2007, 24. 655 Kálmán 2007, 24., 26. 656 Kálmán 2007, 26-28.  ... 
doi:10.15476/elte.2018.086 fatcat:4exmhccolvcu3fk62qxpa4hyue

Fast, parallel implementation of particle filtering on the GPU architecture

Anna Gelencsér-Horváth, Gábor János Tornai, András Horváth, György Cserey
2013 EURASIP Journal on Advances in Signal Processing  
In our work, we focus on a particle filter (PF) [8] which is both part of the SMCM algorithm family and can be considered an extension of a Kalman filter.  ...  Even if each state only depends on the previous state (i.e. the sequence follows the Markov dynamics [6] ), a Kalman filter [7] is suboptimal for the state estimation due to non-linearity and non-Gaussian  ... 
doi:10.1186/1687-6180-2013-148 fatcat:s64g43nv3vcy3g6lnfjqrbkmim
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