David Csercsik | Pázmány Péter Catholic University (original) (raw)

Papers by David Csercsik

arXiv (Cornell University), Sep 12, 2022

The recently experienced disruptions in the EU's energy supply pointed out that supply crises pos... more The recently experienced disruptions in the EU's energy supply pointed out that supply crises pose a real thread and the member states must be better prepared do deal with the related challenges. According to the current practice, member states fill their gas storages independently, while it is not clear how solidarity could be put into practice in the future, i.e. how the accumulated reserves of one or more members may be potentially redistributed to help others in need. In this paper we propose some possible guidelines for a potential solidarity framework, and formalize a game-theoretic model in order to capture the basic features of the problem, considering the related uncertainty of the future conditions related to gas storage levels and possible transmission bottlenecks as well. The proposed mechanism of supply-security related cooperation is based on voluntary participation, and may contribute to the more efficient utilization of storage capacities. Via the computational model we demonstrate the operation of the proposed framework on a simple example and show that under the assumption of risk-averse participants, the concept exhibits potential.

ABSTRACT Assuming wireless communication in scale-free networks, the local routing model can be e... more ABSTRACT Assuming wireless communication in scale-free networks, the local routing model can be extended with a novel approach which takes spatial information into account as well. The properties of the proposed model are analyzed in this paper also when the nodes of the network are moving along straight lines in the unit square. Furthermore, we analyze how reconfiguration affects the throughput and energy efficiency of the network.

In the framework of EUPHEMIA, Minimum Income Condition (MIC) orders are supply orders consisting ... more In the framework of EUPHEMIA, Minimum Income Condition (MIC) orders are supply orders consisting of several hourly step bids for different market hours, bound together by the MIC, which formalizes the requirement that the overall income of the MIC order must cover its given costs, usually composed by a fixed and a variable term. In this paper we introduce a so-called flexible orders, which are also based on the the MIC description, but are composed of mutually exclusive different production profiles. We define the computational formulation of this possible new bid type, and demonstrate the properties of the bid acceptance in the case of two simple two-period examples, considering various market clearing prices (MCPs). We argue that this new type of bid increases the flexibility of day-ahead markets in the presence of price-uncertainty.

Telecommunication Systems, Jul 1, 2016

In this paper we consider a wireless contextualization of the local routing protocol on scale-fre... more In this paper we consider a wireless contextualization of the local routing protocol on scale-free networks embedded in a plane and analyze on the one hand how cooperation affects network efficiency, and on the other hand the stability of cooperation structures. Cooperation is interpreted on k-cliques as local exchange of topological information between cooperating agents. Cooperative activity of nodes in the proposed model changes the routing strategy at the level of the coalition group and consequently influences the entire routing process on the network. We show that the proposed cooperation model enhances the network performance in the sense of reduced passage time and jamming. Payoff of a certain node is defined based on its energy consumption during the routing process. We show that if the payoff of the nodes is the energy saving compared to the all-singleton case, basically coalitions are not stable, since increased activity within coalition increases costs. We introduce coalitional load balancing and net reward to enhance coalitional stability and thus the more efficient operation of the network. As in the proposed model cooperation strongly affects routing dynamics of the network, externalities will arise and the game is defined in a partition function form.

Journal of Theoretical Biology, Nov 1, 2008

In this paper the qualitative dynamic behavior of reaction kinetic models of G protein signaling ... more In this paper the qualitative dynamic behavior of reaction kinetic models of G protein signaling is examined. A simplified basic G protein signaling structure is defined, which is extended to be able to take the effect of slow transmission, RGS mediated feedback regulation and ERK-phosphatase mediated feedback regulation into account. The resulting model gives rise to an acceptable qualitative approximation of the G protein dependent and independent ERK activation dynamics that is in good agreement with the experimentally observed behavior.

Springer eBooks, Sep 8, 2010

IFAC Proceedings Volumes, 2012

GnRH neurons are key elements of the reproductive neuroendocrine system and play important centra... more GnRH neurons are key elements of the reproductive neuroendocrine system and play important central regulating role in the dynamics of the hormonal cycle. A conductance-based Hodgkin-Huxley model structure is proposed in this paper in the form of nonlinear ordinary differential equations that is able to take into account up-to-date biological literature data related to ion channels. Measurement data were available for parameter estimation, which are originated from laboratory experiments done in the Institute of Experimental Medicine of the Hungarian Academy of Sciences in the form of whole cell patch-clamp recordings. The proposed neuron model is highly nonlinear in parameters and the evaluation of the objective function is computationally expensive, therefore the asynchronous parallel pattern search (APPS) procedure has been used for identification which is a gradient-free optimization method that can handle linear equality and inequality constraints and has advantageous convergence properties. The model with high number of estimated parameters provides a qualitatively good fit of both voltage clamp and current clamp traces.

Neurocomputing, Feb 1, 2012

Identifiability analysis of a single Hodgkin-Huxley (HH) type voltage dependent ion channel model... more Identifiability analysis of a single Hodgkin-Huxley (HH) type voltage dependent ion channel model under voltage clamp circumstances is performed in order to decide if one can uniquely determine the model parameters from measured data in this simple case. It is shown that the two steady-state parameters (m 1 , h 1) and the conductance (g) are not globally identifiable together using a single step voltage input. Moreover, no pair from these three parameters is identifiable. Based on the results of the identifiability analysis, a novel optimization-based identification method is proposed and demonstrated on in silico data. The proposed method is based on the decomposition of the parameter estimation problem into two parts using multiple voltage step traces. The results of the article are used to formulate explicit criteria for the design of voltage clamp protocols.

RePEc: Research Papers in Economics, Jun 1, 2014

are circulated to promote discussion and provoque comments. Any references to discussion papers s... more are circulated to promote discussion and provoque comments. Any references to discussion papers should clearly state that the paper is preliminary. Materials published in this series may subject to further publication. Cooperation in traffic routing games on scale free wireless networks

RePEc: Research Papers in Economics, 2020

In this paper we propose a mechanism for the allocation of pipeline capacities, assuming that the... more In this paper we propose a mechanism for the allocation of pipeline capacities, assuming that the participants bidding for capacities do have subjective evaluation of various network routes. The proposed mechanism is based on the concept of bidding for routequantity pairs. Each participant defines a limited number of routes and places multiple bids, corresponding to various quantities, on each of these routes. The proposed mechanism assigns a convex combination of the submitted bids to each participant, thus its called convex combinatorial auction. The capacity payments in the proposed model are determined according to the Vickrey-Clarke-Groves principle. We compare the efficiency of the proposed algorithm with a simplified model of the method currently used for pipeline capacity allocation in the EU (simultaneous ascending clock auction of pipeline capacities) via simulation, according to various measures, such as resulting utility of players, utilization of network capacities, total income of the auctioneer and fairness.

We consider a hybrid model of wireless networks, where nodes are able to communicate with each ot... more We consider a hybrid model of wireless networks, where nodes are able to communicate with each other and a base station as well. We use a coalitional approach for modelling the communication structures and to describe the resulting SINR values and bandwidths. We provide a framework which assumes two frequencies; one for direct communication with the base station and one for internal communication of the mobile devices. Cooperation is interpreted as communication including internal, base-station independent transmission as well. The provided framework is able to evaluate and compare the maximal bandwidth of coalitions in any possible partition structure.

World Academy of Science, Engineering and Technology, International Journal of Electrical, Computer, Energetic, Electronic and Communication Engineering, Sep 29, 2013

munication networks strongly depends on the efficiency of the applied routing mechanism. Game the... more munication networks strongly depends on the efficiency of the applied routing mechanism. Game theoretical approaches to this problem offer new solutions. In this paper a new continuous network routing model is defined to describe data transfer in fixed telecommunication networks of multiple hosts. The nodes of the network correspond to routers whose latency is assumed to be traffic dependent. We propose that the whole traffic of the network can be decomposed to a finite number of tasks, which belong to various hosts. To describe the different latency-sensitivity, utility functions are defined for each task. The model is used to compare router and host intelligent types of routing methods, corresponding to various data transfer protocols. We analyze host intelligent routing as a transferable utility cooperative game with externalities. The main aim of the paper is to provide a framework in which the efficiency of various routing algorithms can be compared and the transferable utility game arising in the cooperative case can be analyzed.

RePEc: Research Papers in Economics, Mar 1, 2013

A cooperative game theoretic framework is introduced to study the behavior of cooperating and com... more A cooperative game theoretic framework is introduced to study the behavior of cooperating and competing electrical energy providers considering price-preference rational consumers. We analyze the interactions of generators in an idealized environment described by a DC load flow model where the network is lossless and is operated by an independent regulator who ensures network stability and fulfillment of consumption needs while taking into account the preferences of consumers over generators. We assume an iterative process in which the generators publish their price offers simultaneously in each step, based on which the consumers preferences are determined. The model deals with network congestion and safety as not every generator-consumer matching is allowed to ensure the fault tolerant operation of the transmission system. To make the model as simple as possible we do not deal with transmission fees, the profit of the generators is determined as the difference between their income, and their production cost which is assumed to be linearly decreasing with the produced quantity. Any non-monopolistic proper subset of the generators may cooperate and harmonize their offered prices to increase their resulting profit. Since we allow the redistribution of profits among cooperating generators, a transferable utility game theoretic framework is used. Furthermore, as cooperation affects the outsiders as well, the resulting game is defined in partition function form. The model is able to demonstrate some interesting benefits of cooperation as well as the effect of market regulations and asymmetric information on the resulting profits and total social cost.

Springer eBooks, 2011

In this paper, an integrative dynamical model of GnRH electrophysiology is used to study the calc... more In this paper, an integrative dynamical model of GnRH electrophysiology is used to study the calcium related interactions corresponding to bursting behavior. Various mechanisms affecting calcium dynamics are blocked or modified, and simulation results are compared to literature data to verify the model.

Complexity, 2018

We propose a discrete time probabilistic model of depositor behavior which takes into account the... more We propose a discrete time probabilistic model of depositor behavior which takes into account the information flow among depositors. In each time period each depositors' current state is determined in a stochastic way, based on their previous state, the state of other connected depositors, and the strategy of the bank. The bank offers payment to impatient depositors (those who want to withdraw their funds) who accept or decline them with certain probability, depending on the offered amount. Our principal aim is to see what are the optimal offers of the bank if it wants to keep the expected chance of a bank run under a certain level and minimize its expected payments, while taking into account the connection structure of the depositors. We show that in the case of the proposed model this question results in a nonlinear optimization problem with nonlinear constraints and that the method is capable of accounting for time-varying resource limits of the bank. Optimal offers increase (a) in the degree of the depositor, (b) in the probability of being hit by a liquidity shock, and (c) in the effect of a neighboring impatient depositor.

Targeted molecular therapies opened new ways and increased the efficiency of cancer therapies. An... more Targeted molecular therapies opened new ways and increased the efficiency of cancer therapies. Antiangiogenic therapy focuses against the growth of tumor by blocking the blood vessel formation of it. Its control engineering perspective has been presented several times, but its key point represents modeling the tumor growth. The purpose of our research is to go beyond the already published minimalistic approach and set up a bi-compartmental (vasculature-dependent tumor growth and angiogenesis) model. The aim of the current paper is to extend our recently published dynamical bicompartmetal model to include the effect of not only for antiangiogenic, but also cytotoxic drugs as well as input. We compare the effect of the two different inputs on the model dynamics in the context of final tumor volume, which can be used as a measure of therapy effectiveness. According to the model prediction, the combination of drugs is more efficient compared to either monotherapy. Furthermore, we compare an optimized open-loop protocol with a very simple intuitive feedback therapy solution.