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This paper implements Simultaneous Localization and Mapping (SLAM) technique to construct a map of a given environment. A Real Time Appearance Based Mapping (RTAB-Map) approach was taken for accomplishing this task. Initially, a 2d occupancy grid and 3d octomap was created from a provided simulated environment. Next, a personal simulated environment was created for mapping as well. In this appearance based method, a process called Loop Closure is used to determine whether a robot has seen a location before or not. In this paper, it is seen that RTAB-Map is optimized for large scale and long term SLAM by using multiple strategies to allow for loop closure to be done in real time and the results depict that it can be an excellent solution for SLAM to develop robots that can map an environment in both 2d and 3d.

This paper explores the relationship between ethnic fractionalization and social capital between 1990-2005. First, using data from 1990, 1997 and 2005 we test for time differences in the impact of ethnic fractionalization on social capital. Subsequently, we examine U.S. data for evidence consistent with the proposed outcomes in the conflict, contact, or hunker-down theses discussed in Putnam (2007). Putnam (2007) examines what happens to “trust" or “social capital" when individuals of different ethnicity are introduced into social, political and/or economic groups over time. Using an instrumental variable (IV) estimator, we find little evidence of heterogeneity in the impact of ethnic fractionalization on social capital over our period of analysis. In addition, using both fixed effect and IV estimators, we reject the contact hypothesis, but find evidence consistent with the outcomes predicted in both the conflict hypothesis and Putnam’s hunker-down hypothesis, in inter-ethnic relations. Due to data limitations, we are unable to test directly which of these two thesis are more relevant for the U.S experience. However, we provide suggestive evidence in support of the conflict hypothesis over the hunker-down hypothesis. Our results suggest that between 1990-2005, as communities in the U.S became more diverse, there was a tendency for social capital to decline.

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Algebra Linear

Typical derivations of kinetic theory equations often exchange the contact time of the particle on a wall with the period of the particle's motion between walls. In this paper we redefine pressure as time-dependent in order to solve this issue and show that this definition makes much more intuitive and theoretical sense than our old definition of pressure.

Este trabalho apresenta o estudo da performance de algoritmos de criptografia em plataformas de Internet das Coisas. O presente trabalho tem como objetivo estudar o funcionamento de algoritmo de criptografia simétrico AES e assimétrico RSA e aplicá-los a ambientes de Internet das Coisas, para que se possa avaliar o impacto na performance dos mesmos. Assim como, aplicar algoritmos de criptografia na camada de rede, na tentativa de garantir a segurança dos dados trocados em um ambiente de Internet das Coisas. Através do estudo, foi verificado que algoritmos assimétricos possuem maior impacto na performance do dispositivo, pois se baseam em cálculos complexos. Com isso, foram escolhidas plataformas utilizadas em prototipagem para mensurar o impacto no processamento. Ao realizar os testes, foi possível provar o impacto na rede e ajudar, através dos dados coletados, a escolher o algoritmo que melhor se adequa ao ambiente de Internet das Coisas, assim como, às necessidades de segurança dos mesmos. Created with the UNIFOR dissertation template

In deze handleiding worden twee technieken beschreven voor visuele cryptografie. Bij de eerste techniek worden twee transparanten met schijnbaar willekeurige patronen van zwarte blokjes over elkaar geschoven om een geheime afbeelding tevoorschijn te laten komen. De tweede techniek gebruikt twee afbeeldingen in grijstinten die transparant over elkaar geschoven worden om een geheime afbeelding op te roepen. De enige voorkennis die nodig is om deze technieken te kunnen uitvoeren, is het gebruik van een rekenblad (hier: Excel) en van een fotobewerkingsprogramma.

A computer is a device that can be instructed to carry out sequences of arithmetic or logical operations automatically via computer programming. Modern computers have the ability to follow generalized sets of operations, called programs. These programs enable computers to perform an extremely wide range of tasks. Conventionally, a modern computer consists of at least one processing element, typically a central processing unit (CPU), and some form of memory. The processing element carries out arithmetic and logical operations, and a sequencing and control unit can change the order of operations in response to stored information. Peripheral devices include input devices (keyboards, mice, joystick, etc.), output devices (monitor screens, printers, etc.), and input/output devices that perform both functions (e.g., the 2000s-era touchscreen). Peripheral devices allow information to be retrieved from an external source and they enable the result of operations to be saved and retrieved.(Demo Document )

Linux es un sistema operativo: un conjunto de programas que permiten interactuar con el ordenador y ejecutar otros programas. La parte ms importante de un sistema operativo es el ncleo. En un sistema GNU/Linux, Linux es el ncleo. El Shell es el programa-interface y es un script para la terminal que solo tenemos que agregar la extensión .sh que provee la comunicacin entre el usuario y el Sistema operativo, sus funciones son: Servir como traductor de comandos, recibe los comandos internos del mismo sistema operativo y Shell se encarga de su ejecucin, en cambio si hablamos de comandos realizados por el usuario entre la funcin del kernel, el los ejecuta y se encarga de procesar sus rdenes.