Complex networks, including the Internet, wireless and cellular networks, and on-line social networks, are becoming indispensable parts of our daily lives. These networks arising from a wide range of applications can be represented and studied as graphs, and the underlying link patterns play an important role in understanding and solving problems in such applications. For example, many online social networks, such as Twitter and Google+, can be viewed as directed graphs with uni-directional "following'' relations among users, and the link directions contain crucial information about how users form social communities. In another application, online social networks such as Slashdot and Epinions represent relationships between users as links with positive or negative weights, which correspond to friend and foe relations. These networks are referred to as signed networks, where those signed links generate new challenges in understanding and studying the underlying network properties. In this talk, I present my work on developing theories for studying and characterizing various crucial graph properties, such as the edge directionality in directed graphs and the edge polarity in signed graphs. I do so by emphasizing on applications to detecting stable social communities and understanding social influence propagation patterns on online social networks.

​With an optimistic assumption that a WiFi Access Point (AP) is idle for 50% of the time, an approximate energy waste caused exclusively by WiFi APs worldwide is estimated to be a striking 4.7 Billion KWh/year. Furthermore, many other types of future wireless network devices are expected to spend substantial amounts of energy in their idle listening modes, including wireless sensor and actuator nodes, wireless smart meters, mobile phones, and cellular base stations.

In this talk, I will discuss the complex relationship between the university research lab and the startup community and how it varies in different places. There will be some emphasis on software focused startups as these are quite special in terms of the low capital investment costs required to deliver an initial working product, but the talk will also consider the wider set of high tech startup enterprises, some of which are built on a deep understanding of a problem domain arising from substantial research. The talk will discuss the similarities and differences between the activities and skills of the research lab and the startup.

The purpose of this seminar is to provide an introduction to state-of-art technologies and standards related to mobile multi-hop wireless networks, as broadly classified into three categories depending on their typical coverage: broadband wireless access (BWA), wireless local area networks (WLAN) and wireless personal area networks (WPAN).

Ponente: Iljitsch van Beijnum, Ayudante de Investigación, Institute IMDEA Networks
Lugar: Aula 4. 1F03, Departamento de Telemática, Edificio Torres Quevedo, Universidad Carlos III de Madrid, Avda. Universidad, 30, 28911 Leganes – Madrid
Fecha: 25 de mayo 2011, 13:00
Organización: NETCOM Research Group (Departamento de Telemática, Universidad Carlos III de Madrid, España); Institute IMDEA Networks (Madrid, España)
 

El seminario se impartirá en inglés

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