G+: Enhanced Traffic Grooming in WDM Mesh Networks using Lighttours

In this article, a new technique for grooming low-speed traffic demands into high-speed optical routes is proposed. This enhancement allows a transparent wavelength-routing switch (WRS) to aggregate traffic en route over existing optical routes without incurring expensive optical-electrical-optical (OEO) conversions. This implies that: a) an optical route may be considered as having more than one ingress node (all inline) and, b) traffic demands can partially use optical routes to reach their destination. The proposed optical routes are named "lighttours" since the traffic originating from different sources can be forwarded together in a single optical route, i.e., as taking a "tour" over different sources towards the same destination. The possibility of creating lighttours is the consequence of a novel WRS architecture proposed in this article, named "enhanced grooming" (G+). The ability to groom more traffic in the middle of a lighttour is achieved with the support of a simple optical device named lambda-monitor (previously introduced in the RingO project). In this article, we present the new WRS architecture and its advantages. To compare the advantages of lighttours with respect to classical lightpaths, an integer linear programming (ILP) model is proposed for the well-known multilayer problem: traffic grooming, routing and wavelength assignment The ILP model may be used for several objectives. However, this article focuses on two objectives: maximizing the network throughput, and minimizing the number of optical-electro-optical conversions used. Experiments show that G+ can route all the traffic using only half of the total OEO conversions needed by classical grooming. An heuristic is also proposed, aiming at achieving near optimal results in polynomial time

All-Optical Label Stacking: Easing the Trade-offs Between Routing and Architecture Cost in All-Optical Packet Switching

All-optical label swapping (AOLS) forms a key technology towards the implementation of all-optical packet switching nodes (AOPS) for the future optical Internet. The capital expenditures of the deployment of AOLS increases with the size of the label spaces (i.e. the number of used labels), since a special optical device is needed for each recognized label on every node. Label space sizes are affected by the way in which demands are routed. For instance, while shortest-path routing leads to the usage of fewer labels but high link utilization, minimum interference routing leads to the opposite. This paper studies all-optical label stacking (AOLStack), which is an extension of the AOLS architecture. AOLStack aims at reducing label spaces while easing the compromise with link utilization. In this paper, an integer lineal program is proposed with the objective of analyzing the softening of the aforementioned trade-off due to AOLStack. Furthermore, a heuristic aiming at finding good solutions in polynomial-time is proposed as well. Simulation results show that AOLStack either a) reduces the label spaces with a low increase in the link utilization or, similarly, b) uses better the residual bandwidth to decrease the number of labels even more

TU Graz: Course: 707.000 Web Science and Web Technology: Lecture 2: Small World Problem

We will discuss several examples and research efforts related to the small world problem and set the ground for our discussion of network theory and social network analysis. Readings: An Experimental Study of the Small World Problem, J. Travers and S. Milgram Sociometry 32 425-443 (1969) [Protected Access] Optional: The Strength of Weak Ties, M.S. Granovetter The American Journal of Sociology 78 1360--1380 (1973) [Protected Access] Optional: Worldwide Buzz: Planetary-Scale Views on an Instant-Messaging Network, J. Leskovec and E. Horvitz MSR-TR-2006-186. Microsoft Research, June 2007. [Web Link, the most recent and comprehensive study on the subject!] Originally from: http://kmi.tugraz.at/staff/markus/courses/SS2008/707.000_web-science/

Arc Length

Exam questions and solutions in LaTex

Arc Length pdf

Exam questions and solutions in PDF

El Programa Partnership i l'estudi de problemes mediambientals a l'IES Josep Sureda i Blanes

El objetivo del programa Partnership es trabajar problemas medioambientales en diversos centros escolares de diferentes pa??ses europeos para que se tome consciencia que los problemas del medio ambiente no son locales sino que nos afectan a todos. Se trata de un proyecto interdisciplinar en el que est??n implicados alumnos y profesores de diferentes departamentos. Las comunicaciones entre los centros participantes son una parte importante del proyecto. En las Baleares participan cuatro institutos de ense??anza secundaria, entre ellos el IES Josep Sureda i Blanes, que trata la problem??tica del agua potable en Palma. Este instituto se ha asociado con centros de caracter??sticas similares de Dinamarca, Inglaterra y Gibraltar, que trabajan el mismo tema. El art??culo recoge las aportaciones de este IES al proyecto a partir del an??lisis de la ciudad de Palma de Mallorca, especialmente el an??lisis sensorial de la salinidad del agua. Se concluye que la experiencia ha sido positiva para el alumnado en tanto ha servido para tomar conciencia de un problema ambiental local y las soluciones adoptadas para resolverlo.

Using Problem Steps Recorder on Windows 7

Problem Steps Recorder is a standard piece of software on Windows 7 computers, which allows you to record a sequence of actions on your computer, along with screenshots. It can help ServiceLine diagnose any problems that you might be experiencing.

Problem-Based Learning Using CaseMaker - Richard Collier

This is one of a series of short case studies describing how academic tutors at the University of Southampton have made use of learning technologies to support their students.

SB.TV's successful yet unconventional establishment of a Brand based solely on Social Network Success may present a problem in long-term survival

Research Proposal in SB.TV case study. New dimension to brand model for Web 2.0 success

El casal d'infants d'Eivissa : una iniciativa per a fam??lies amb problem??tica social. 'La casa de ni??os de Eivissa : una iniciativa para familias con problem??tica social'

Resumen tomado de la propia publicaci??n. Los autores son miembros del equipo de atenci??n primaria de los servicios sociales del ayuntamiento de la ciudad de Eivissa

Modelling for Problem Solving in the Large

This a short presentation which introduces how models and modelling help us to solve large scale problems in the real world. It introduces the idea that dynamic behaviour is caused by interacting components in the system. Feedback in the system makes behaviour prediction difficult unless we use modelling to support understanding

Hiding routing information

This is the original "onion routing" paper, it explains in the details how onions are built and work. This is optional reading, although I strongly advise you to read the Introduction and section 3 "Onions"

El enfoque diferencial de género en la implementación de políticas públicas en procesos de desmovilización y reintegración. Estudio de caso: el rol de la madre cabeza de hogar en la implementación de la política de reintegración del grupo insurgente ARC-EP (2002-2012)”

El presente trabajo tiene como objetivo analizar la política pública de reintegración para grupos armados insurgentes, desde un enfoque diferencial de género. En este enfoque la investigación destaca el rol de madre cabeza de familia excombatiente.