Nicolas D. Georganas

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In wireless sensor networks that consist of a large number of low-power, short-lived, unreliable sensors, one of the main design challenges is to obtain long system lifetime, as well as maintain sufficient sensing coverage and reliability. In this paper, we propose a node-scheduling scheme, which can reduce system overall energy consumption, therefore(More)
In wireless sensor networks that consist of a large number of low-power, short-lived, unreliable sensors, one of the main design challenges is to obtain long system lifetime without scarifying system original performances (sensing coverage and sensing reliability). In this paper, we propose a node-scheduling scheme, which can reduce system overall energy(More)
Recent traffic measurements in corporate LANs, Variable-bit-rate video sources, ISDN control-channels and other communication systems, have indicated traffic behaviour of self-similar nature. This paper first discusses some definitions and properties of (second-order) self-similarity and gives simpler criteria for it. It then gives a model of self-similar(More)
This paper presents a novel and real-time system for interaction with an application or videogame via hand gestures. Our system includes detecting and tracking bare hand in cluttered background using skin detection and hand posture contour comparison algorithm after face subtraction, recognizing hand gestures via bag-of-features and multiclass support(More)
In light of the slow deployment of IP Multicast technology on the global Internet and the explosive popularity of peer-to-peer file-sharing applications, there has been a flurry of research activities investigating the feasibility of implementing multicasting capability at the application layer, referred to as Application Layer Multicasting (ALM), and(More)
This paper reviews and briefly discusses the known definitions and properties of second-order self-similar discretetime processes and supplements them with some more general conditions of self-similarity. A model for ATM cell traffic is presented and self-similarity conditions of this model are found. This study is motivated by recently made observations(More)
Synchronous collaboration in virtual reality spaces has specific requirements that differ from those of other application data, leading to a different communication approach. Update messages corresponding to the change in the state of a shared object must be communicated both reliably and in a timely manner among users. While a lot of research has been done(More)
RECAL, a Recursion by Chain Algorithm for computing the mean performance measures of product-form multiple-chain closed queueing networks, is presented. It is based on a new recursive expression which relates the normalization constant of a network with r closed routing chains to those of a set of networks having (r-l) chains. It relies on the artifice of(More)
This paper proposes a two level approach to solve the problem of real-time vision-based hand gesture classification. The lower level of the approach implements the posture recognition with Haar-like features and the AdaBoost learning algorithm. With this algorithm, real-time performance and high recognition accuracy can be obtained. The higher level(More)