Raspberry Pi-pohjainen dataloggeri

Dataloggerit ovat tärkeitä mittaustekniikassa käytettäviä mittalaitteita, joiden tarkoituksena on kerätä talteen mittausdataa pitkiltä aikaväleiltä. Dataloggereita voidaan käyttää esimerkiksi teollista prosessia osana olevien toimilaitteiden tai kotitalouden energiajärjestelmän seurannassa. Teollisen luokan dataloggerit ovat yleensä hinnaltaan satojen tai tuhansien eurojen luokkaa. Työssä pyrittiin löytämään teollisen luokan laitteille halpa ja helppokäyttöinen vaihtoehto, joka on kuitenkin riittävän tehokas ja toimiva. Työssä suunniteltiin ja toteutettiin dataloggeri Raspberry Pi-alustalle ja testattiin sitä oikeaa teollista ympäristöä vastaavissa olosuhteissa. Kirjallisuudesta ja internet artikkeleista etsittiin samankaltaisia laite- ja ohjelmistoratkaisuja ja niitä käytettiin dataloggausjärjestelmän pohjana. Raspberry Pi-alustalle koodattiin yksinkertainen Python-kielinen data-loggausohjelma, joka käyttää Modbus-tiedonsiirtoprotokollaa. Testien perusteella voidaan todeta, että toteutettu dataloggeri on toimiva ja kykenee kaupallisten dataloggereiden tasoiseen mittaukseen ainakin pienillä näytteistystaajuuksilla. Toteutettu dataloggeri on myös huomattavasti kaupallisia dataloggereita halvempi. Helppokäyttöisyyden näkökulmasta dataloggerissa havaittiin puutteita, joita käydään läpi jatkokehitysideoiden muodossa.

Estudo comparativo de métodos de regionalização hidrológica e desenvolvimento de um aplicativo para o gerenciamento de outorga de águas superficiais

Dissertação (mestrado)—Universidade de Brasília, Instituto de Geociências, 2016.

Trace Oblivious Program Execution

The big data era has dramatically transformed our lives; however, security incidents such as data breaches can put sensitive data (e.g. photos, identities, genomes) at risk. To protect users' data privacy, there is a growing interest in building secure cloud computing systems, which keep sensitive data inputs hidden, even from computation providers. Conceptually, secure cloud computing systems leverage cryptographic techniques (e.g., secure multiparty computation) and trusted hardware (e.g. secure processors) to instantiate a “secure” abstract machine consisting of a CPU and encrypted memory, so that an adversary cannot learn information through either the computation within the CPU or the data in the memory. Unfortunately, evidence has shown that side channels (e.g. memory accesses, timing, and termination) in such a “secure” abstract machine may potentially leak highly sensitive information, including cryptographic keys that form the root of trust for the secure systems. This thesis broadly expands the investigation of a research direction called trace oblivious computation, where programming language techniques are employed to prevent side channel information leakage. We demonstrate the feasibility of trace oblivious computation, by formalizing and building several systems, including GhostRider, which is a hardware-software co-design to provide a hardware-based trace oblivious computing solution, SCVM, which is an automatic RAM-model secure computation system, and ObliVM, which is a programming framework to facilitate programmers to develop applications. All of these systems enjoy formal security guarantees while demonstrating a better performance than prior systems, by one to several orders of magnitude.

Análise gráfica de estruturas porosas sobre a ótica da estereologia

In this work we developed a computer simulation program for physics porous structures based on programming language C + + using a Geforce 9600 GT with the PhysX chip, originally developed for video games. With this tool, the ability of physical interaction between simulated objects is enlarged, allowing to simulate a porous structure, for example, reservoir rocks and structures with high density. The initial procedure for developing the simulation is the construction of porous cubic structure consisting of spheres with a single size and with varying sizes. In addition, structures can also be simulated with various volume fractions. The results presented are divided into two parts: first, the ball shall be deemed as solid grains, ie the matrix phase represents the porosity, the second, the spheres are considered as pores. In this case the matrix phase represents the solid phase. The simulations in both cases are the same, but the simulated structures are intrinsically different. To validate the results presented by the program, simulations were performed by varying the amount of grain, the grain size distribution and void fraction in the structure. All results showed statistically reliable and consistent with those presented in the literature. The mean values and distributions of stereological parameters measured, such as intercept linear section of perimeter area, sectional area and mean free path are in agreement with the results obtained in the literature for the structures simulated. The results may help the understanding of real structures.

Tutankamón

O presente trabalho pretende apresentar e descrever a metodologia processual e respectivas relexões que sustentam a criação de um artefato digital interativo construído de forma a que alguns dos elementos bidimensionais que o constituem sejam manipuladas de forma a que criem ao jogador a ilusão de tridimensionalidade. Em 1992 a Id Software com o jogo Wolfenstein 3D, introduziu uma referência visual à tridimensionalidade, utilizando para o efeito tecnologia 2D, a qual, através de um sistema de redimensionamento e posicionamento de imagens, consegui transmitir a noção de tridimensionalidade, utilizando na altura um tipo de jogo em primeira pessoa, ou seja, o jogador experiência uma campo visual que visa reproduzir a própria experiência do mundo táctil na relação que dispõe entre os espaços e objetos. Através do Processing, uma linguagem de programação que assenta no Java, estes objetivos conceptuais serão reproduzidos, que procuram, por um lado, transmitir esta aparente ilusão de tridimensionalidade e por outro não utilizar um tipo de artefacto digital que proporciona uma jogabilidade em primeira pessoa mas sim possibilitam ao jogador uma experiência visual que aborda todo o espaço em que é lhe permitido circular, no qual é lhe exposto as adversidades que precisa de superar para progredir. Para que isto seja possível o jogador assume o papel de um personagem e através da sua interação com o artefato, vai ediicando uma narrativa visual que visa o seu envolvimento com a temática representada. Como tema é utilizada uma representação da busca pelo Sarcófago do faraó da 18ª Dinastia Tutankamón (1332 - 1323 AC) pelo explorador britânico Howard Carter (1874 - 1939) cuja expedição no Vales do Reis em 1922 constitui ainda hoje a mais célebre descoberta arqueológica relacionada com Antigo Egipto. Ao longo desta Dissertação são abordados temas que visam resoluções tanto no campo técnico e tecnológico, através da programação e sua linguagem, como no campo visual e estético que visa uma conexão consciente com a temática a representar e a ser experienciada

Jogo para aprender a programar

Neste documento foi feita a apresentação do conceito de Programação Visual, estudados alguns exemplos de Linguagens de Programação Visual e investigado vantagens e desvantagens sobre o seu uso comparativamente à programação tradicional (por texto) e, adicionalmente, foram estudados três jogos para aprender a programar com fortes características visuais. A partir desta investigação, foi criada uma nova Linguagem de Programação Visual(LPV) sendo a base de um prototipo de um jogo para aprender a programar. Este jogo é representado pela deslocação e execução de tarefas feitas por um robô dentro de uma casa, sendo o objetivo do programador colocar objetos nesta casa que manipulam a deslocação do robô dentro desta de forma a resolver um problema; Abstract: A game to learn programming Aplication of concepts of visual programming to create a game to learn how to program In this document we will explain the concept of Visual Programming, study some examples of Visual Programming Languages, analyze some arguments in favor and against its use in comparison to traditional programming (by text) and, additionally, study three games to learn programming with strong visual features. Using this research, a new Visual Programming Language(VPL) was created, being the basis of a prototype of a game to learn programming. This game is represented by the movement and execution of tasks done by a robot inside a house, being the goal of the programmer to place objects in this house that manipulate the movement of the robot inside of it in order to solve a problem.

Interoperability Challenges in Internet of Things Systems: a Service-Oriented Computing Approach

Internet of Things systems are pervasive systems evolved from cyber-physical to large-scale systems. Due to the number of technologies involved, software development involves several integration challenges. Among them, the ones preventing proper integration are those related to the system heterogeneity, and thus addressing interoperability issues. From a software engineering perspective, developers mostly experience the lack of interoperability in the two phases of software development: programming and deployment. On the one hand, modern software tends to be distributed in several components, each adopting its most-appropriate technology stack, pushing programmers to code in a protocol- and data-agnostic way. On the other hand, each software component should run in the most appropriate execution environment and, as a result, system architects strive to automate the deployment in distributed infrastructures. This dissertation aims to improve the development process by introducing proper tools to handle certain aspects of the system heterogeneity. Our effort focuses on three of these aspects and, for each one of those, we propose a tool addressing the underlying challenge. The first tool aims to handle heterogeneity at the transport and application protocol level, the second to manage different data formats, while the third to obtain optimal deployment. To realize the tools, we adopted a linguistic approach, i.e.\ we provided specific linguistic abstractions that help developers to increase the expressive power of the programming language they use, writing better solutions in more straightforward ways. To validate the approach, we implemented use cases to show that the tools can be used in practice and that they help to achieve the expected level of interoperability. In conclusion, to move a step towards the realization of an integrated Internet of Things ecosystem, we target programmers and architects and propose them to use the presented tools to ease the software development process.

Big Code Applications and Approaches

The availability of a huge amount of source code from code archives and open-source projects opens up the possibility to merge machine learning, programming languages, and software engineering research fields. This area is often referred to as Big Code where programming languages are treated instead of natural languages while different features and patterns of code can be exploited to perform many useful tasks and build supportive tools. Among all the possible applications which can be developed within the area of Big Code, the work presented in this research thesis mainly focuses on two particular tasks: the Programming Language Identification (PLI) and the Software Defect Prediction (SDP) for source codes. Programming language identification is commonly needed in program comprehension and it is usually performed directly by developers. However, when it comes at big scales, such as in widely used archives (GitHub, Software Heritage), automation of this task is desirable. To accomplish this aim, the problem is analyzed from different points of view (text and image-based learning approaches) and different models are created paying particular attention to their scalability. Software defect prediction is a fundamental step in software development for improving quality and assuring the reliability of software products. In the past, defects were searched by manual inspection or using automatic static and dynamic analyzers. Now, the automation of this task can be tackled using learning approaches that can speed up and improve related procedures. Here, two models have been built and analyzed to detect some of the commonest bugs and errors at different code granularity levels (file and method levels). Exploited data and models’ architectures are analyzed and described in detail. Quantitative and qualitative results are reported for both PLI and SDP tasks while differences and similarities concerning other related works are discussed.

Typed behavioural equivalences in the Pi-Calculus

In this thesis, I study the notion of program equivalences, i.e. proving that two programs can be used interchangeably without altering the overall observable behaviour. This definition is highly dependent on the contexts in which these programs can be used; does the context have exceptions, parallelism, etc... So proofs also need to be adapted according to the expressiveness of those contexts. This thesis presents on the pi-calculus – a concurrent programming language – under various typing constraints. Types allows us to impose different disciplines like forcing a sequential execution, or ensuring linearity, meaning an object can be used once. In each case, the bisimulation, a standard proof technique for the pi-calculus, needs to be adapted accordingly to obtain a suitable equivalence. We then test how using the modified bisimulations can be used to reason about a language with higher-order functions and references, which once translated into the pi-calculus satisfies the typing constraints.

Towards a logical foundation of randomized computation

This dissertation investigates the relations between logic and TCS in the probabilistic setting. It is motivated by two main considerations. On the one hand, since their appearance in the 1960s-1970s, probabilistic models have become increasingly pervasive in several fast-growing areas of CS. On the other, the study and development of (deterministic) computational models has considerably benefitted from the mutual interchanges between logic and CS. Nevertheless, probabilistic computation was only marginally touched by such fruitful interactions. The goal of this thesis is precisely to (start) bring(ing) this gap, by developing logical systems corresponding to specific aspects of randomized computation and, therefore, by generalizing standard achievements to the probabilistic realm. To do so, our key ingredient is the introduction of new, measure-sensitive quantifiers associated with quantitative interpretations. The dissertation is tripartite. In the first part, we focus on the relation between logic and counting complexity classes. We show that, due to our classical counting propositional logic, it is possible to generalize to counting classes, the standard results by Cook and Meyer and Stockmeyer linking propositional logic and the polynomial hierarchy. Indeed, we show that the validity problem for counting-quantified formulae captures the corresponding level in Wagner's hierarchy. In the second part, we consider programming language theory. Type systems for randomized \lambda-calculi, also guaranteeing various forms of termination properties, were introduced in the last decades, but these are not "logically oriented" and no Curry-Howard correspondence is known for them. Following intuitions coming from counting logics, we define the first probabilistic version of the correspondence. Finally, we consider the relationship between arithmetic and computation. We present a quantitative extension of the language of arithmetic able to formalize basic results from probability theory. This language is also our starting point to define randomized bounded theories and, so, to generalize canonical results by Buss.

PExIL: Programming Exercises Interoperability Language

Several standards appeared in recent years to formalize the metadata of learning objects, but they are still insufficient to fully describe a specialized domain. In particular, the programming exercise domain requires interdependent resources (e.g. test cases, solution programs, exercise description) usually processed by different services in the programming exercise life-cycle. Moreover, the manual creation of these resources is time-consuming and error-prone leading to what is an obstacle to the fast development of programming exercises of good quality. This paper focuses on the definition of an XML dialect called PExIL (Programming Exercises Interoperability Language). The aim of PExIL is to consolidate all the data required in the programming exercise life-cycle, from when it is created to when it is graded, covering also the resolution, the evaluation and the feedback. We introduce the XML Schema used to formalize the relevant data of the programming exercise life-cycle. The validation of this approach is made through the evaluation of the usefulness and expressiveness of the PExIL definition. In the former we present the tools that consume the PExIL definition to automatically generate the specialized resources. In the latter we use the PExIL definition to capture all the constraints of a set of programming exercises stored in a learning objects repository.

Making programming exercises interoperable with PExIL

Several standards have appeared in recent years to formalize the metadata of learning objects, but they are still insufficient to fully describe a specialized domain. In particular, the programming exercise domain requires interdependent resources (e.g. test cases, solution programs, exercise description) usually processed by different services in the programming exercise lifecycle. Moreover, the manual creation of these resources is time-consuming and error-prone, leading to an obstacle to the fast development of programming exercises of good quality. This chapter focuses on the definition of an XML dialect called PExIL (Programming Exercises Interoperability Language). The aim of PExIL is to consolidate all the data required in the programming exercise lifecycle from when it is created to when it is graded, covering also the resolution, the evaluation, and the feedback. The authors introduce the XML Schema used to formalize the relevant data of the programming exercise lifecycle. The validation of this approach is made through the evaluation of the usefulness and expressiveness of the PExIL definition. In the former, the authors present the tools that consume the PExIL definition to automatically generate the specialized resources. In the latter, they use the PExIL definition to capture all the constraints of a set of programming exercises stored in a learning objects repository.

Child programming: an adequate domain specific language for programming specific robots

Dissertação para obtenção do Grau de Mestre em Engenharia Informática

A programming environment having three levels of complexity for mobile robotics = Entorno de programación con tres niveles de complejidad para robótica móvil

This paper presents a programming environment for supporting learning in STEM, particularly mobile robotic learning. It was designed to maintain progressive learning for people with and without previous knowledge of programming and/or robotics. The environment was multi platform and built with open source tools. Perception, mobility, communication, navigation and collaborative behaviour functionalities can be programmed for different mobile robots. A learner is able to programme robots using different programming languages and editor interfaces: graphic programming interface (basic level), XML-based meta language (intermediate level) or ANSI C language (advanced level). The environment supports programme translation transparently into different languages for learners or explicitly on learners’ demand. Learners can access proposed challenges and learning interfaces by examples. The environment was designed to allow characteristics such as extensibility, adaptive interfaces, persistence and low software/hardware coupling. Functionality tests were performed to prove programming environment specifications. UV BOT mobile robots were used in these tests