Patrick Wüchner

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This paper proposes a retrial queueing model with the finite number of sources to evaluate the performance of spectrum renting in mobile cellular networks. The model incorporates necessary ingredients such as the finite number of subscribers, their impatience and a queue for the outbound service. To consider the specific feature of spectrum renting and the(More)
Available online xxxx Keywords: Performance modeling Finite-source retrial queues Orbital search Balking customers Impatient customers MOSEL-2 a b s t r a c t The present paper deals with a generalization of the homogeneous multi-server finite-source retrial queue with search for customers in the orbit. The novelty of the investigation is the introduction(More)
wireless sensor networks using finite-source retrial queues with unreliable orbit. Abstract. Motivated by the need for performance models suitable for modeling and evaluation of wireless sensor networks, we introduce a retrial queueing system with a finite number of homogeneous sources, unreliable servers, orbital search, and unreliable orbit. All random(More)
A method to derive local interaction strategies for improving cooperation in self-organizing systems. Abstract. To achieve a preferred global behavior of self-organizing systems , suitable local interaction strategies have to be found. In general, this is a non-trivial task. In this paper, a general method is proposed that allows to systematically derive(More)
Since the entities composing self-organizing systems have direct access only to information provided by their vicinity, it is a non-trivial task for them to determine properties of the global system state. However, this ability appears to be mandatory for certain self-organizing systems in order to achieve an intended functionality. Based on Shannon's(More)
We consider a retrial queueing system with a finite number of homogeneous sources of calls and a single server. Each source generates a request after an exponentially distributed time. An arriving customer finding the server idle enters into service immediately; otherwise the customer enters into an orbit. The service times are supposed to be exponentially(More)
This paper deals with the performance analysis of multiple server retrial queueing systems with a finite number of homogeneous sources of calls, where the heterogeneous servers are subject to random breakdowns and repairs. The requests are serviced according to Random Selection and Fastest Free Server disciplines. The novelty of this investigation is the(More)
Some cellular automata are able to solve classification problems on their initial configuration by building globally visible structures. However, no formal measures exist yet for describing or detecting this behavior in general. The lack of such formal methods often leads to quite observer-dependent discussions of emergent computation. In this paper, we(More)
This paper gives a systematic overview on modeling formalisms suitable for modeling self-organizing systems. We distinguish between micro-level model-ing and macro-level modeling. On the micro level, the behavior of each entity and the interaction between different object must be described by the model. Macro-level modeling abstracts from the individual(More)