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We introduce a new symbolic reflection API for implementing tool-independent summaries for the symbolic execution of C programs. We formalise the proposed API as a symbolic semantics and extend two state-of-the-art symbolic execution tools with support for it. Using the proposed API, we implement 67 tool-independent symbolic summaries for a total of 26 libc functions. Furthermore, we present SumBoundVerify, a fully automatic summary validation tool for checking the bounded correctness of the symbolic summaries written using our symbolic reflection API. We use SumBoundVerify to validate 37 symbolic summaries taken from 3 state-of-the-art symbolic execution tools, angr, Binsec and Manticore, detecting a total of 24 buggy summaries., LIPIcs, Vol. 263, 37th European Conference on Object-Oriented Programming (ECOOP 2023), pages 24:1-24:29

The artifact contains the extended versions of the tools angr and AVD with support for the symbolic reflection API proposed in the paper. Additionally, the artifact contains the source code of SumBoundVerify, our novel tool for the bounded-verification of symbolic summaries for the C programming language. The artifact contains all the scripts and datasets required to obtain the results presented in the paper, including: a library of 67 symbolic summaries implemented using the proposed symbolic reflection API; two symbolic test suites designed to test two open source C libraries; and the source code of the third-party summaries that were validated checked with SumBoundVerify., DARTS, Vol. 9, Special Issue of the 37th European Conference on Object-Oriented Programming (ECOOP 2023), pages 7:1-7:4

WebAssembly (Wasm) is a new binary instruction format that allows targeted compiled code written in high-level languages to be executed by the browser’s JavaScript engine with near-native speed. Despite its clear performance advantages, Wasm opens up the opportunity for bugs or security vulnerabilities to be introduced into Web programs, as pre-existing issues in programs written in unsafe languages can be transferred down to cross-compiled binaries. The source code of such binaries is frequently unavailable for static analysis, creating the demand for tools that can directly tackle Wasm code. Despite this potentially security-critical situation, there is still a noticeable lack of tool support for analysing Wasm binaries. We present WASP, a symbolic execution engine for testing Wasm modules, which works directly on Wasm code and was built on top of a standard-compliant Wasm reference implementation. WASP was thoroughly evaluated: it was used to symbolically test a generic data-structure library for C and the Amazon Encryption SDK for C, demonstrating that it can find bugs and generate high-coverage testing inputs for real-world C applications; and was further tested against the Test-Comp benchmark, obtaining results comparable to well-established symbolic execution and testing tools for C., LIPIcs, Vol. 222, 36th European Conference on Object-Oriented Programming (ECOOP 2022), pages 11:1-11:29

This artifact contains the implementation of WASP, a symbolic execution engine for Wasm, and WASP-C, a symbolic execution framework for testing C programs built using WASP . WASP works directly on Wasm code and was built on top of a standard-compliant Wasm reference implementation [Andreas Haas et al., 2017]. WASP was thoroughly evaluated: it was used to symbolically test a generic data-structure library and the Amazon Encryption SDK for C, demonstrating that it can find bugs and generate high-coverage testing inputs for real-world C applications; WASP was further tested against the Test-Comp benchmark, obtaining results comparable to well-established symbolic execution and testing tools for C., DARTS, Vol. 8, Special Issue of the 36th European Conference on Object-Oriented Programming (ECOOP 2022), pages 20:1-20:3

Dissertação de Mestrado em Ensino de Educação Física, nos Ensinos Básico e Secundário Quando um aluno é agredido ou se converte em vítima e está exposto, de uma forma repetitiva e durante um tempo, as ações negativas que são levadas a cabo por um ou mais alunos estão sujeitos a uma situação de bullying (Olweus, 1993). Este fenómeno constitui hoje um problema amplamente difundido por inúmeras investigações, quer no estrangeiro quer em Portugal. De modo a dar resposta às situações de bullying, tem sido desenvolvidos programas e projetos, bem como realizados estudos sobre esta realidade, com consideráveis evidências que podem ser eficazes na sua redução, quando consideramos a realidade de cada escola e de todos os agentes educativos nela envolvidos. O presente estudo teve por objetivo diagnosticar a realidade dos comportamentos de bullying/vitimização no contexto escolar, segundo a perspetiva do próprio aluno, comparando a frequência que ocorrem por sexo e por ciclo de escolaridade. Investigou as formas de bullying/vitimização mais frequentes e os locais onde ocorrem. O instrumento utilizado neste estudo, foi um questionário intitulado “ A agressividade entre os jovens no espaço escolar” adaptação do questionário de Dan Olweus (1989), feita por Nascimento (1995) e para o tratamento de dados utilizou-se o programa estatístico SPSS e o teste de Mann – Whitney. Participaram 172 alunos de ambos os sexos, sendo 89 do 3º ciclo do Ensino Básico com idades compreendidas entre os 13 e os 15 anos e 83 do Ensino Secundário, com idades compreendidas entre os 16 e os 19 anos. Os resultados apontam para um número elevado de estudantes envolvidos no processo de bullying, havendo uma diferença significativa entre os alunos do 3º Ciclo e Secundário. No entanto, apesar de em termos percentuais encontrarmos algumas diferenças em relação ao sexo, as diferenças não são significativas. O total da nossa amostra evidencia que o local onde ocorrem com mais frequência os comportamentos de bullying /vitimização é o recreio. Conclui-se que o bullying é um fenómeno de ocorrência muito comum e um problema grave nas escolas por todo o mundo e é um assunto pelo qual nos devemos preocupar. Espera-se que os resultados deste estudo alertem alunos, professores e encarregados de educação para o problema. When a student is attacked or becomes a victim and is exposed in a repetitive manner and for a time, the negative actions that are carried out by one or more students are placed in a situation of bullying (Olweus, 1993). This phenomenon today is a widespread problem for many investigations, either abroad or in Portugal. In order to respond to bullying situations, programs and projects have been developed and conducted studies on this reality, with considerable evidence that can be effective in reducing it, when we consider the reality of each school and all education agents it involved. The present study aimed to diagnose the reality of bullying behaviors/victimization in the school context , according to the student's own perspective, comparing the frequency that occur by gender and schooling cycle. Investigated forms of bullying / victimization more frequently and where they occur. The instrument used in this study was a questionnaire titled “The aggression among youth in school " adaptation of Dan Olweus (1989 ) , made by Nascimento (1995) questionnaire and the data processing SPSS was used and Mann - Whitney test . 172 students of both sexes, with 89 of the 3rd cycle of basic education aged 13 to 15 years and 83 Secondary School, aged between 16 and 19 years participated. The results indicate a high number of students involved in the bullying process, there is a significant difference between the students of the 3rd cycle and secondary school. However, though in percentage terms we find some differences in relation to gender, the differences are not significant. The total of our sample shows that the location where the most frequently occurring behaviors of bullying / victimization is playtime. It is concluded that bullying is a phenomenon very common occurrence and a serious problem in schools throughout the world and is a subject in which we should worry. It is expected that the results of this study warn students, teachers and parents to the problem.

A small scale trigeneration system for combined heat, cold and power production was developed and installed at the Laboratório Nacional de Energia e Geologia, I.P. campus in Lisbon, Portugal. This system is one of the twelve experimental trigeneration systems being developed and tested across Europe within the PolySMART project. The CHCP system main constituents are a purpose made CHP prototype with an estimated 27kW maximum heat capacity and 9,6kW maximum electrical capacity and a TDC prototype with 8kW cooling power. The hydraulic scheme is presented and briefly analyzed. The data obtained during the monitoring of the system during heat and cold seasons is presented and analyzed for the global system. Main components behavior is analyzed with regard of their real performance when installed on a CHCP system.

This work is a TRNSYS simulation of solar thermal system working together with an existing small sized CHCP (Combinet Heat Cooling and Power) demonstration project, included in the workpackage 5 (simulation) of the PolySMART project. The first objective of this work is to fine tune simulation parameters of the simulation Units (or Types), based on monitoring data collected during the first semester of 2010. The second objective is to further develop the mathematical models of type 107 (Hot Water-Fired Single-Effect Absorption Chiller) and type 120 (HYDROGEMS: Diesel Engine Generator System (DEGS) - Version 1.1). This will tackle the remaining differences between the real and simulated systems. These differences are due to the fact that both the CHP and the Ammonia-Water Air Cooled Chiller are prototypes. The third objective is to simulate the performance of different thermal collectors, some of which are also prototypes, and choose a proper solution for future experiments. The forth objective is to compare local weather data sets, collected on site since 2007, with proven standard data sets. Further work may be developed regarding the fan coils used to carry in/out heat.

Relatório de estágio de mestrado em Estatística e Investigação Operacional, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, em 2018 Submitted by Cristina Manessiez (camanessiez@fc.ul.pt) on 2019-01-14T18:19:57Z No. of bitstreams: 1 ulfc124634_tm_Alexandre_Torrejano.pdf: 2955303 bytes, checksum: 97f197060bb55c0841b64d0bbf373008 (MD5) Made available in DSpace on 2019-01-14T18:20:09Z (GMT). No. of bitstreams: 1 ulfc124634_tm_Alexandre_Torrejano.pdf: 2955303 bytes, checksum: 97f197060bb55c0841b64d0bbf373008 (MD5) Previous issue date: 2018