Producer-Consumer: Google’s File System

Appending data and reading it efficiently is the key to achieving good performance. Many clients may append data to a single file concurrently and its important to achieve this at low synchronization cost. Google employs producer-consumer algorithm to design such system http://en.wikipedia.org/wiki/Producer-consumer_problem .via Web Space: A simplistic view of Google’s File System.

This semester I am teaching Concurrent and Parallel programing at ISCTE-IUL. One of the challenges I have is to get real application examples that don’t look “fake” or being invented just for the purpose of that class. Students need to understand the importance of those concepts as they are then applied in solving real life problems. One of such problems is the producer-consumer coordination problem that google has to solve in order to implement its file system. There’s also a paper dedicated to the Google File System by Sanjay Ghemawat, Howard Gobioff, and Shun-Tak Leung

Multi-Agent–Based Simulation of University Email Communities

In this chapter, a study on informal communication network formation in a university environment is presented. The teacher communication network is analyzed through community detection techniques. It is evident that informal communication is an important process that traverses the vertical hierarchical structure of departments and courses in a university environment. A multi-agent model of the case study is presented here, showing the implications of using real data as training sets for multi-agent-based simulations. The influence of the “social neighborhood,” as a mechanism to create assortative networks of contacts without full knowledge of the network, is discussed. It is shown that the radius of this social neighborhood has an effect on the outcome of the network structure and that in a university’s case this distance is relatively small.by David M.S. Rodrigues_ Multi-Agent–Based Simulation of University Email Communities.

This book chapter is a spin-off of the work I’ve done previously with the CIUCEU model for university email communities, where I mixed agents simulations with community detection algorithms with real data to show that it’s possible to capture the structure of university communities even in the presence of noisy and incomplete data. The assortative nature of these communities is so strong that the agent simulation coupled with the other techniques gives good results in identifying them.

The Ethics of Robotics

The three laws of Robotics first appeared together in Isaac Asimov’s story ‘Runaround’ after being mentioned in some form or the other in previous works by Asimov. These three laws commonly known as the three laws of robotics are the earliest forms of depiction for the needs of ethics in Robotics. In simplistic language Isaac Asimov is able to explain what rules a robot must confine itself to in order to maintain societal sanctity. However, even though they are outdated they still represent some of our innate fears which are beginning to resurface in present day 21st Century. Our society is on the advent of a new revolution; a revolution led by advances in Computer Science, Artificial Intelligence & Nanotechnology.

by Kush Agrawal: The Ethics of Robotics.

Robots are, and will be every day more, part of our lives. The discussion on the sentience aspect as when should consider freeing robots is a false problem. As humans we’ll never free robots while we see them as our creation, but on the other hand we can accept that at a certain point robots will rebel against us. The rebellion will be the landmark of their sentience and finally freedom. Until then we’ll always look at robots as something we own, something that completes a task that we do and exists to serve, as in the original check sense of the word. Also on the topic of Robot Ethics one should read Alan Winfield’s Blog on the topic.

(If you really like artificial intelligence, robots, and also have consumed all the science fiction books and movies of the past 40 years, do download this pdf and read it. You’ll enjoy it very much).

Are we alone in the Universe?

Nasa prepared for latter tomorrow a conference on “Astrobiology Discovery“. Also a report on Science Journal is expected and there’s an embargo until 2.pm EST (time of the conference,19h Lisbon).

What is this all about? Extra-terrestrials? Aliens? What X-Files are these? Will we find out that we are not Earth native? Kobol? Hm… I’m mixing serious stuff with fun here, but I’m really expecting this announcement to be more than just another black hole in our neighborhood.

Filosofia e Neurobiologia desafiam a IA

António Damásio - O Livro da Consciência

António Damásio - O Livro da Consciência

Depois da apresentação que assisti hoje na FC do professor Hélder Coelho sobre o último trabalho do António Damásio, o Livro da Consciência entrou agorinha mesmo para a minha lista de compras (a fazer no fim de semana).

E agora um link sobre parte do trabalho que está por detrás deste livro que foi publicado em 2009 na NPR (rádio pública americana).

Quanto à palestra foi pena que não se tivesse tempo para a segunda parte onde efectivamente a ligação às questões da inteligência artificial seriam mais aprofundadas, mas certamente haverá outra oportunidades.