A linguagem C não provê segurança espacial de memória: não garante que a memória acessada através de um ponteiro para um objeto, tal como um vetor, de fato pertence ao objeto em questão. Em vez disso, o programador é responsável por gerenciar informações de alocações e limites, e garantir que apenas acessos válidos à memória são realizados pelo programa. Por um lado, isso provê flexibilidade: o programador tem controle total sobre o layout dos dados em memória, e sobre o momento em que verificações são realizadas. Por outro lado, essa é uma fonte frequente de erros e vulnerabilidades de segurança em programas C. Diversas técnicas já foram propostas para prover segurança de memória em C. Tipicamente tais sistemas mantêm suas próprias informações de limites e instrumentam o programa para garantir que a segurança de memória não seja violada. Isso causa uma série de inconvenientes, tais como mudanças no layout de memória de estruturas de dados, quebrando assim a compatibilidade binária com bibliotecas externas, e/ou um aumento no consumo de memória. Uma abordagem diferente consiste em usar tipos dependentes para descrever a informação de limites já latente em programas C e assim permitir que o compilador use essa informação para garantir a segurança espacial de memória. Embora tais sistemas tenham sido propostos no passado, eles estão atrelados especificamente à linguagem C. Outras linguagens, como C++, sofrem de problemas similares de segurança de memória, e portanto poderiam se beneficiar de uma abordagem mais independente de linguagem. Este trabalho propõe Týr, uma transformação de código baseada em tipos dependentes para garantir a segurança espacial de memória de programas C ao nível LLVM IR. O sistema permite que o programador descreva no nível dos tipos as relações entre pointeiros e informação de limites já presente em programas C. Dessa maneira, Týr provê segurança espacial de memória verificando o uso consistente desses metadados pré-existentes, através de verificações em tempo de execução inseridas no programa guiadas pela informação de tipos dependentes. Ao trabalhar no nível mais baixo do LLVM IR, Týr tem por objetivo ser usável como uma fundação para segurança espacial de memória que possa ser facilmente estendida no futuro para outras linguagens compiláveis para LLVM IR, tais como C++ e Objective C. Demonstramos que Týr é eficaz na proteção contra violações de segurança espacial de memória, com um overhead de tempo de execução relativamente baixo e de consumo de memória próximo de zero, atingindo assim um desempenho competitivo com outros sistemas para segurança espacial de memória de uma maneira mais independente de linguagem. / The C programming language does not enforce spatial memory safety: it does not ensure that memory accessed through a pointer to an object, such as an array, actually belongs to that object. Rather, the programmer is responsible for keeping track of allocations and bounds information and ensuring that only valid memory accesses are performed by the program. On the one hand, this provides flexibility: the programmer has full control over the layout of data in memory, and when checks are performed. On the other hand, this is a frequent source of bugs and security vulnerabilities in C programs. A number of techniques have been proposed to provide memory safety in C. Typically such systems keep their own bounds information and instrument the program to ensure that memory safety is not violated. This has a number of drawbacks, such as changing the memory layout of data structures and thus breaking binary compatibility with external libraries and/or increased memory usage. A different approach is to use dependent types to describe the bounds information already latent in C programs and thus allow the compiler to use that information to enforce spatial memory safety. Although such systems have been proposed before, they are tied specifically to the C programming language. Other languages such as C++ suffer from similar memory safety problems, and thus could benefit from a more language-agnostic approach. This work proposes Týr, a program transformation based on dependent types for ensuring spatial memory safety of C programs at the LLVM IR level. It allows programmers to describe at the type level the relationships between pointers and bounds information already present in C programs. In this way, Týr ensures spatial memory safety by checking the consistent usage of this pre-existing metadata, through run-time checks inserted in the program guided by the dependent type information. By targeting the lower LLVM IR level, Týr aims to be usable as a foundation for spatial memory which could be easily extended in the future to other languages that can be compiled to LLVM IR, such as C++ and Objective C. We show that Týr is effective at protecting against spatial memory safety violations, with a reasonably low execution time overhead and nearly zero memory consumption overhead, thus achieving performance competitive with other systems for spatial memory safety, in a more language-agnostic way.

Made available in DSpace on 2014-10-09T12:26:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:32Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A análise de tintas e papéis é de grande interesse para a ciência e a interação tinta-papel é importante em vários níveis. A análise da tinta de um documento é extremamente importante para o estudo de diferentes aspectos, como adulterações e determinação da recentidade. Esses aspectos podem ser estudados analisando a tinta e o papel tanto fisicamente quanto quimicamente. Portanto, o desenvolvimento de uma técnica para a análise de tintas de caneta esferográfica e a determinação da recentidade de um documento é interessante para a Ciência Forense. No Brasil, cientistas forenses enfrentam todos os dias diversos casos que requerem a análise de tintas de caneta esferográfica, e não se tem nenhuma técnica onde a determinação da idade de uma tinta é possível. Os casos mais comuns onde há a necessidade da recentidade de um documento são fraudes em recibos de pagamento e de quitação de dívidas, preenchimento e assinatura de contratos, adulteração em documentos e em cheques. Neste trabalho, é discutida uma nova metodologia para a análise de tintas de canetas esferográficas e a sua utilização na determinação da recentidade de uma amostra de tinta de caneta esferográfica. Foram analisadas periodicamente amostras provenientes de diferentes países, como Estados Unidos, Canadá, Peru, Japão, Espanha e Grécia. Com os resultados obtidos, foram construídas curvas de degradação do solvente em função do tempo de preparo. Com as curvas, obtiveram-se as equações logarítmicas relativas. As equações propostas mostraram ser capazes de distinguir a idade relativa de uma tinta, com 20% de variação em relação ao valor teórico. Portanto, a principal conclusão deste trabalho é a metodologia proposta pode ser utilizada para determinar a idade relativa de uma tinta de caneta esferográfica. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP / FAPESP:05/58301-0

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / O trabalho trata da expressÃo da futuridade nos tipos de discurso das ordens do expor e do narrar e investiga a variaÃÃo entre formas â como presente do indicativo, perÃfrase ir + infinitivo e futuro do presente do indicativo, na ordem do expor, e como imperfeito do indicativo, perÃfrase ir + infinitivo e futuro do pretÃrito do indicativo, na ordem do narrar â que codificam subdomÃnios funcionais de expressÃo de futuridade baseados nos tipos de discurso. SÃo objetivos do trabalho: a) delimitar subdomÃnios funcionais de expressÃo da futuridade, relacionando-os aos tipos de discurso do expor e do narrar, baseando-se na perspectiva interacionista social, de Bronckart (2003); b) analisar a variaÃÃo entre as formas acima, usando princÃpios e metodologia da Teoria da variaÃÃo e mudanÃa, de Labov (2008). A pesquisa analisa dados obtidos do uso da lÃngua, provenientes de corpora das modalidades oral e escrita, produzidos no CearÃ, e busca fatores linguÃsticos e sociais que possam condicionar o uso das variantes, submetendo esses dados a tratamento estatÃstico atravÃs do pacote computacional VARBRUL. Os resultados mostram que o valor e o uso das formas investigadas sÃo diferentes nos diferentes tipos de discurso. No discurso interativo, da ordem do expor, ir + infinitivo foi a variante preferida, mas no discurso teÃrico, tambÃm da ordem do expor, a variante preferida foi o futuro do presente. No relato interativo, da ordem do narrar, a variante mais usada foi ir + infinitivo, e, na narraÃÃo, tambÃm da ordem do narrar, foi o futuro do pretÃrito. Os resultados mostram tambÃm que grupos de fatores linguÃsticos, como projeÃÃo da futuridade, e grupos de fatores sociais, como idade e sexo, sÃo relevantes na variaÃÃo das formas em questÃo nos tipos de discurso observados. O grupo de fatores linguÃsticos projeÃÃo da futuridade mostra que parece existir uma relaÃÃo entre as variantes e a expressÃo de mais ou menos certeza sobre o futuro. Os contextos de mais certeza sÃo reservados para as formas do presente e imperfeito do indicativo na expressÃo da futuridade. O grupo de fatores idade sugere, em linhas gerais, que hà um processo de mudanÃa no qual ir + infinitivo està assumindo a funÃÃo de expressÃo de futuridade em lugar do futuro do presente e futuro do pretÃrito do indicativo. O processo de mudanÃa parece ser mais avanÃado no discurso interativo e no relato interativo, entretanto, no discurso teÃrico e na narraÃÃo o processo à incipiente. O grupo de fatores sexo sugere, como a teoria sociolinguÃstica hipotetiza, que as mulheres assumem a implementaÃÃo da nova variante (ir + infinitivo) quando o processo de mudanÃa à mais avanÃado, mas os homens usam com mais frequÃncia a nova forma no comeÃo do processo de mudanÃa. Outros grupos de fatores, como paradigma verbal, ocorrÃncia da forma em construÃÃo verbal maior e futuridade quanto à limitaÃÃo sugerem que princÃpios funcionalistas, como o princÃpio da retenÃÃo (BYBEE, 2003) e o princÃpio das regras de quantidade (GIVON, 2001), tÃm influÃncia no uso das variantes. / The research deals with the expression of futurity in the types of discourse of the exposition and of the narration orders and investigates the variation between forms â as indicative present, periphrasis ir + infinitive and indicative present future, in the exposition order, and as indicative imperfect past, periphrasis ir + infinitive and indicative past future, in the narration order â that codify functional subdomains of expression of futurity based on that types of discourse. It has as objectives: a) to delimit functional subdomains of expression of futurity, relating them to the types of discourse of the exposition and narration orders, basing on the social interactionist perspective of Bronckart (2003); b) to analyze the variation between the forms above, using principles and methodology of the Theory of variation and change of Labov (2008). It analyzes data from language use, originated from corpora of oral and written modalities, produced in CearÃ, and it searches for linguistics and social factors that can determine the use of the variants, submitting this data to statistic treatment on the computational pack VARBRUL. The results show that the value and the use of the investigated variants are different, so are different the types of discourse. In interactive discourse, of the exposition order, ir + infinitive was the preferred variant, although in theoretical discourse, of the exposition order too, the preferred variant was indicative present future. In the related discourse, of the narration order, the most used variant was ir + infinitive, and, in the narration, of the narration order, it was indicative past future. The results show also that linguistic factor groups, as projection of futurity, and social factor groups, as age and gender, are relevant in the variation of the analyzed forms in the types of discourse observed. Projection of futurity lingugistic factor group shows that seems to exist a relation between the variants and the expression of more or less certainty about the future. The contexts of more certainty are reserved especially to the forms of simple present and imperfect past on the expression of futurity. The social factor group age suggests, in a general line, that there is a process of change, in that ir + infinitive is assuming the function of expression of futurity in the place of indicative present future and past future. This process of change seems to be more advanced in the interactive discourse and in the related discourse, although, in the theoretical discourse and in the narration, the process is incipient. Gender factor group suggests, as the sociolinguistics theory has as hypothesis, that women assume the implementation of the new variant (ir + infinitive) when the process of change is more advanced, but men use with more frequency the new form in the beginning of the change process. Other factor groups, as verbal paradigm, occurrence of the form in a bigger verbal construction and limitation of futurity suggest that functionalist principles, as the principle of retention (BYBEE, 2003) and the principle of the quantity rules (GIVÃN, 2001), have influence in the use of variants.

It is the purpose of this study to investigate the possibilities of a new instrument designed to measure authoritarian personalities.

Le présent projet de recherche est dédié à la formalisation et à l'intégration des méthodologies de conception et validation à la phase de conception détaillée, afin de favoriser les échanges de connaissances entre les acteurs impliqués dans le processus de développement de produits. La conception détaillée implique des interactions entre trois éléments : la géométrie, les matériaux et les chargements. Conséquemment, dans le cadre de cette thèse qui intègre plusieurs articles, les liens entre ces trois éléments seront formalisés au niveau des méthodologies de conception. Plus spécifiquement, les méthodologies de conception proposées seront centrées sur la phase de conception détaillée. En effet, dans la littérature existante, peu d'articles s'attardent à décrire les processus itératifs selon lesquels un concept est développé en produit dans le respect des critères de conception mentionnés dans le cahier de charges et tout en gardant le lien avec les connaissances disciplinaires et les outils d'assistance actuels. Il faudra donc envisager des méthodologies de conception détaillée qui cibleront plusieurs critères de conception et qui s'adapteront à divers types de produits. À l'étape de conception détaillée, dans le cadre du processus de développement de produits, il faudra également intégrer l'optimisation et la validation de produits. Les activités d'optimisation permettent de trouver une ou plusieurs combinaisons de paramètres maximisant ou minimisant un critère de conception donné, tandis que les activités de validation fournissent une rétroaction au concepteur, afin de vérifier l'exactitude des calculs réalisés et l'atteinte de tous les critères de conception. L'application d'une décomposition des étapes représente une stratégie qui sera utilisée pour le développement de méthodologies de conception et de validation de produits. Les sous-étapes qui en résulteront seront plus faciles à accomplir et à gérer. Qui plus est, les sous-étapes peuvent interagir entre elles, donc les concepteurs doivent s'assurer que la solution obtenue suite à une étape ne viole pas les hypothèses ou les contraintes d'une autre sous-étape complémentaire. La méthodologie de conception et de validation de produits structuraux, qui en a résulté suite à ce programme de recherche, a été appliquée en milieu industriel dans le but de prouver sa contribution au développement de ce type des produits. Un des gains les plus importants apportés par cette méthodologie c'est qu'on a réussi à réduire le nombre d'itérations au niveau de l'étape de validation expérimentale tout en assurant la rétroaction sur les besoins du client et sur les spécifications du produit. Cette réduction du nombre d'itération au niveau de la validation expérimentale sera transposée également dans une réduction du temps de validation. Finalement, suite à l'application de la nouvelle approche méthodologique, on a été en mesure de développer une composante structurale qui devrait respecter plusieurs critères à la fois et de déterminer d'une manière scientifique sa durée de vie tout en minimisant son surdimensionnement.

>Magister Scientiae - MSc / The objective of this study was to determine the hydrosalinity fluxes associated with overland and subsurface (vadose zone) flow for different soils and land uses. For this purpose, the following data were collected during 2005 and 2006 in a typical small scale catchment located near the town of Riebeeck-Wes: weather data, hydrological and water quality measurements, soil water contents and chemistry, and vegetation growth. The area is characterized by a Mediterranean climate receiving winter rainfall of approximately 300 mm a catchment is conservative, with Na + and Cl- being the dominant ions.

Magister Public Health - MPH / Background: Disclosure in the context of HIV is the sharing of information about one’s HIV-positive status with someone else. In the case of people living with HIV (PLHIV), many factors influence their decision to disclose. As with other illnesses there is a concern about possible discrimination or stigma. On the other hand, disclosure can lead to higher levels of support and better management of HIV infection. Types of disclosure can also vary depending on the need of the PLHIV, being partial or full, in order to gain the most benefit. Self-disclosure or mediated disclosure with the assistance of someone else is controlled by the PLHIV, whereas involuntary or forced disclosure might not be under the PLHIV's control and thus more likely to have negative consequences. No studies have been done in the rural area of Linguère, Senegal or in the rest of the country to identify the factors that influence the decisions of PLHIV around disclosure. Senegal has a concentrated HIV epidemic with national HIV prevalence stable at 0.7% in 2005 and 2010 Demographic and Health Surveys. Linguère District's HIV prevalence was at 0.8% in 2003. By knowing more about what motivates PLHIV to disclose or not disclose their status, service providers and others can better support PLHIV to practise beneficial disclosure. Aim: The aim of this study was to explore factors that influence the decision to disclose or not disclose one's HIV-positive status to regular sexual partners, friends and family in Linguère District,Senegal. Methods: A qualitative method with in-depth interviews was used to explore the factors that influenced decisions concerning disclosure. Fifteen PLHIV were identified through purposive sampling based on criteria such as marital status, gender and prior disclosure decisions. In addition, four service providers from the AIDS service organization, Projet SSP, and the district health and social workers served as key informants. The interviews were recorded, transcribed and translated from the local languages into French. Record reviews of the HIV/AIDS service organization complemented the interviews. The fieldwork was conducted in the study setting for two weeks in January 2012. The data was analysed through thematic analysis. Findings: The main themes that emerged as reasons for disclosure were maintaining psychosocial well-being, existence of trusting relationships, need for support with health care, reciprocal obligations and concern for others, whereas reasons for non-disclosure included stigma and discrimination and negative impact on family. However, the factors varied from one participant to another and could not consistently be attributed to one group or another, whether man or woman, married or divorced,etc. Influencing factors were related to gaining support for the participant or avoiding problems. Concerns about stigma were great and included reference to wanting others to have soutoura— privacy, dignity, respect. There were also factors which took into consideration the consequence for the person to whom they might disclose, such as desire to avoid upset or desire to seek testing and possible care for a spouse. Of the participants who had disclosed, there were no cases of severe negative consequences. Not one participant expressed regret for having disclosed, rather they acknowledged that there were positive benefits for themselves and sometimes also the other person to whom disclosure was made. The roles of the service providers and the support group were also influential in decision-making around disclosure, with a good number of cases of mediated disclosure. Conclusion: In line with consequence theory, PLHIV weighed up their benefits and costs when decisions around disclosure were contemplated. The benefits were that PLHIV who chose to disclose gained from increased social support and better management of their HIV infection. At the same time further transmission of infection was potentially reduced and others were oriented for testing and for access to care if needed. In general, HIV continues to be a particularly stigmatising condition and thus the majority of PLHIV in this study judged that it is not worth the risk of possible abandonment,rejection or slander to disclose their status, regardless of the fact that few have actually experienced severe negative consequences as a result of actual disclosure. Because of support provided through service providers and the support group, however, those participants who had chosen to disclose to someone outside of the support group were reaping benefits and also likely avoiding the need to turn to risky activities, such as transactional sex or formal sex work. Recommendations: Recommendations drawn from this study include the need to support programmes or initiatives which seek to reduce HIV-related stigma. There is also the need for leaders in the community to show support for PLHIV which can reduce stigma. Health care and service providers should be aware of the needs of PLHIV and the changes that may arise over time which could lead to a decision to practise beneficial disclosure. They should also learn from the experiences shared by other PLHIV which can in turn be shared. They should receive further training in order to better understand the complexity of disclosure and to assist with mediated disclosure.

Long distance running has become increasingly popular in Hong Kong and some middle-aged men take up running in midlife. This research studies the transformative learning that occurs when they practise long distance running in midlife and how it contributes to midlife transition. At the beginning of the study, four hypotheses were developed based on researcher’s observations and literature review. Thirteen middle-aged Hong Kong male runners were then interviewed in a semi-structured way. Thirty-four themes were identified from the data and analysed. The hypotheses were evaluated and arguments of this thesis were then developed. It is then found that long distance running mirrors some real life situations of middle-aged men, triggers transformative learning, and provides the setting for them to reflect on and practise the transformed beliefs and values. When running and the associated transformation address the initial concerns of the middle-aged men, and they are able to resolve difficulties in running with proper methods and find ways to enjoy running, long distance running becomes part of their lives. Long distance running is then a high leverage activity which addresses other midlife concerns and contributes to other life aspects and midlife transition. Moreover, those who were good at sports as teenagers and did not exercise regularly in mid-adulthood are found to benefit more easily from taking up long distance running in midlife. This study extends the application of transformative learning theory to understand and facilitate midlife transition and shows that a single routine activity, like long distance running, can be a multi-function activity in the transformative learning process and a high leverage activity for midlife transition that contributes to multiple life aspects.

The research portrayed in this dissertation aims to derive empirical means of predicting CBR values from index testing parameters and parameters calculated from them (e.g. shrinkage product). The project involved compiling a database of test results for a range of rock material types across moist and dry regions in southern Africa. The database was compiled in such a way that it represents natural gravels sampled (mostly) for construction or rehabilitation of road layer works. The database included a location description, material description, Weinert N-Value, Atterberg Limits, grading analysis and CBR values. In addition to this, the linear shrinkage product, shrinkage product, grading coefficient, grading modulus and dust ratio were calculated and also used in the analyses. All the samples were divided into two groups based on climate, as described by Weinert (1980). The data was then further sub-divided into compaction classes (95%, 98% and 100% Mod AASHTO) and within these compaction classes, each sample was assigned to a rock material group based on the classification proposed by Weinert (1980), but with minor alterations (e.g. further subdivision of pedogenic deposits). A total of 60 groups were created. Data processing was done using grading normalised to 100% passing the 37,5mm screen. In order to limit interdependency resulting from the cumulative grading, the sieve analysis results were converted to percentages retained on each sieve. This was necessary as statistical regressions often rejected datasets due to interdependency among input parameters (such as Atterberg Limits and cumulative grading). Based on the nature of the data, both stepwise linear regressions and Weibull regressions were performed. Though the Weibull regression is more suitable to the data (in theory) the linear regression could not be excluded, due to variable data. In addition, the existing model proposed by Kleyn (1955) which was derived empirically by Stephens (1988) was also retained for the analysis. In an attempt to refine Kleyn s model, the two parameters used by the method (i.e. grading modulus and plasticity index) were used in normal linear regressions in an attempt to adapt the model to specific material (and compaction) groups in the two climatic regions. More than 130 regressions were done for the final analysis (excluding experimental regressions, etc.), after restricting the predicted CBR ranges in an attempt to eliminate the prevailing data trend. The attempt proved futile, though, placing severe restrictions on the derived models. For each of the 60 groups all four methods were tested (i.e. stepwise linear regression, Weibull regression, Kleyn s model and a linear model adapted for each group based on Kleyn s model) and the most suitable model selected. A number of regressions were incomplete due to insufficient data, particularly in the groups associated with dry regions. Results proved poor and are ascribed to data variability rather than test methods. The data variability, in turn, is the result of test methods with poor reproducibility and repeatability. In short, the test methods (the CBR in particular) resulted in inconsistent data and subsequently poor results, making accurate predictions nearly impossible. / Dissertation (MSc)--University of Pretoria, 2010. / Geology / unrestricted

Main goal of this thesis is to design module of communication for a small company specializing in development of complex software. There are communication problems in project management, that result in loss of important informations. I will present the theoretical principles of project communication and use them to identify main problems. Using this conclusions I will design a new internal system module and install it into organization, then i will summarize feedback received from employes. At the end of the thesis i will evaluate benefits for the organization.