Game Theory – Correlated Equilibrium

“In game theory, a correlated equilibrium is a solution concept that is more general than the well known Nash equilibrium. It was first discussed by mathematician Robert Aumann (1974). The idea is that each player chooses his/her action according to his/her observation of the value of the same public signal. A strategy assigns an action to every possible observation a player can make. If no player would want to deviate from the recommended strategy (assuming the others don’t deviate), the distribution is called a correlated equilibrium.” – from Wikipedia

In the following case of study, the concepts of game theory, Nash equilibrium and correlated equilibrium are used to reach the goal.

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Approximation algorithm for partial set cover

The set cover problem (SCP)  is a classical question in combinatorics, computer science and complexity theory.

Briefly, a set of elements and a set of sets that contains different elements are given. Each set has an associated cost. The goal is cover every elements paying the less cost possible.

The partial set cover is a slightly different problem, in which is required to cover at least a given percentage of items paying the less cost possible. The problem is known to be NP-complete, but using approximation good results can be achieved with ease. In the following we analyze the correctness of a greedy approximation algorithm for partial set cover.

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Super-fast NTFS driver for Linux

Using NTFS drives with a Linux distribution can be a painful experience due the lack of optimized drivers. Starting from first linux releases, a lot a bugs in the ntfs driver were present that caused a lot of problems as reported everywhere on the internet.

Today I’ve found a really powerful (and highly optimized) driver that solved my issues, thanks to Paragon Software Group.

This great software house distributes a FREE FOR PERSONAL USE ONLY driver that works flawless on Ubuntu (as well as other distro) and solved all my problems (from exceptional high cpu usage to very poor transfer rate).

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GPS and temperature logger – PART I

With some free time (and an unused GPS module) I decided to realize a GPS and temperature logger. It can be used for example to check if a good was moved through the right path and within a given temperature range.

gps_temp_logger_main

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STM32F4-Discovery LCD Touchscreen

It’s time to write about a more complex but interesting connection with the STM32F4-Discovery board. Since I started developing with electronics, I’ve found a lot of applications in which an LCD is needed or can be an added value, specially if it includes a Touchscreen.

stm32f4_ssd1289

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