12 pp. / Pine Bark Beetles, THE PIÑON IPS BARK BEETLE, FIREWOOD AND BARK BEETLES IN THE SOUTHWEST, USING INSECTICIDES TO PREVENT BARK BEETLE ATTACKS ON CONIFERS, GUIDELINES FOR THINNING PONDEROSA PINE FOR IMPROVED FOREST HEALTH AND FIRE PREVENTION / Various techniques to reduce brood production of Ips and Dendroctonus spp. in ponderosa pine slash are discussed.

Priskonvergens är en teoretisk slutsats av ett flertal ekonomiska teorier, samt ett väl undersökt område som visat sig vara ett statistiskt signifikant faktum i olika ekonomiska regioner. Priskonvergens kräver i teorin och empirin att ekonomierna är likriktade och har liknande ekonomiska förutsättningar, krav som den inomeuropeiska marknaden uppfyller. Här har också priskonvergens bevisats vara ett statistiskt signifikant faktum i ett flertal studier. Förutom de studier vari detta bevisats redovisas också teorier som kan förklara  priskonvergensen, i denna uppsats redovisas bland annat lagen om ett pris, teorin om köpkraftsparitet samt utbuds- och efterfrågeteori. Något som torde leda till ytterligare ekonomisk konvergens och därmed också priskonvergens är en gemensam valuta, och efter euroinförandet genomfördes flera studier i syfte att klargöra huruvida det teoretiska antagandet om stärkt priskonvergens inom en valutaunion kunde stämma. Dessutom testades i dessa studier om EU-kommissionen haft rätt i sitt uttalande om att priskonvergensen skulle bli stärkt mellan de länder som anslöt sig till valutasamarbetet. Resultatet från studierna varierar och det är här denna uppsats tar vid. Problemformuleringen lyder: ”Har införandet av den gemensamma valutan euro i lett till en stärkt priskonvergens mellan de länder som antagit valutan?” Problemet undersöks med hjälp av regressionsanalys där ett modifierat prisjämförelseindex används som beroende variabel. Den viktigaste oberoende variabeln i analysen är en dummyvariabel som visar priskonvergensen innan och efter euroinförandet inom de aktuella länderna. Slutsatsen av den genomförda analysen är att euron inte påverkat priskonvergensen inom euroområdet. Dock bevisades att priskonvergens är ett statistiskt signifikant faktum i EU-regionen som helhet.

A especificação abstrata de tipos de dados, a hoje um dos conceitos mais importantes, aceitos e compreendidos da Ciência da Computação, que permite descrever as principais entidades de um sistema baseado em computador através das propriedades que tais entidades devem satisfazer. Isto a feito usando métodos e linguagens algébricos, onde as propriedades são definidas na forma de axiomas (equações). Por outro lado, a tecnologia chamada de Orientada a Objetos (00), foi se transformando em uma disciplina amadurecida para projetos e implementações de aplicações de software. Atualmente esta tecnologia inclui muitas metodologias e muitas linguagens que abrangem todo o processo de desenvolvimento de sistemas, porem, a maioria delas são influenciadas pela implementação de tais sistemas, isto e, os conceitos básicos 00 de classe, objeto e herança são definidos em fungi° da linguagem de implementação a ser usada. Alem disso, notamos que nos últimos anos esta sendo desenvolvida muita pesquisa sobre uma geração de computadores que envolvem massivamente arquiteturas paralelas (computação concorrente), bem como sobre sistemas de comunicação de dados e engenharia (descrição) de protocolos. O objetivo principal desta tese a dar uma resposta a estes três assuntos integrando três conceitos básicos da Engenharia de Software: Especificação Algébrica, Orientação a Objetos e Especificação de Processos e Concorrência, em uma Única abordagem expressa através de uma Linguagem de Especificação Formal, chamada LOP. Esta linguagem a de natureza algébrica, com destaque para a semântica baseada em teorias em lógica de primeira ordem e na construção incremental de especificações baseada em bibliotecas. / The abstract specification of data types, one of the most important concepts accepted and understood of the Computer Science, allows to describe the the main entities of a based-computer system through the properties that these entities should be to satisfy. This is made using algebraic methods and languages, where the properties are defined as axioms (equations). By other hand, the technology called Object-Oriented (00), it has been transformed in a mature discipline for Design and Implementations of software applications. At present, this technology include many methodologies and many languages for the totality of the system development process. But the majority are influenced by the implementation of such systems, i.e., the basic concepts 00 of class, object and inheritance are defined in accordance with the programming language to be used. Moreover, we noted that the last years are being developed many research on a computer generation that involve massively parallel architectures (concurrent computing) as well as on data communication systems and protocol engineering (description). The main objective of this thesis is to give an answer to these three subjects integrating three basic concepts of Software Engineering: Algebraic Specification, Object Orientation and Processes and Concurrency specification, in an unique approach expressed through a language of formal specification, called LOP. This language has algebraic nature with prominence to the semantics based on theories in first-order logic with equality and the incremental construction of library-based specifications.

Fuzz testing is a random testing technique that is effective at finding bugs in large software programs and protocols. We investigate if the technology can be used to find bugs in multi-threaded applications by fuzzing a real-time embedded avionics platform together with a tool specialized at finding data races between multiple threads. We choose to fuzz an API (available to applications executing on top) of the platform. This thesis evaluates aspects of integrating a fuzzing program, AFL and a sanitizer, ThreadSanitizer with an embedded system. We investigate the modifications needed to create a correct run-time environment for the system, including supplying test data in a safe manner and we discuss hardware dependencies. We present a setup where we show that the tools can be used to find planted data races, however slowdown introduced by the tools is significant and the fuzzer only managed to find very simple planted data races during the test runs. Our findings also indicate what appear to be conflicts in instrumentation between the fuzzer and the sanitizer.

A especificação abstrata de tipos de dados, a hoje um dos conceitos mais importantes, aceitos e compreendidos da Ciência da Computação, que permite descrever as principais entidades de um sistema baseado em computador através das propriedades que tais entidades devem satisfazer. Isto a feito usando métodos e linguagens algébricos, onde as propriedades são definidas na forma de axiomas (equações). Por outro lado, a tecnologia chamada de Orientada a Objetos (00), foi se transformando em uma disciplina amadurecida para projetos e implementações de aplicações de software. Atualmente esta tecnologia inclui muitas metodologias e muitas linguagens que abrangem todo o processo de desenvolvimento de sistemas, porem, a maioria delas são influenciadas pela implementação de tais sistemas, isto e, os conceitos básicos 00 de classe, objeto e herança são definidos em fungi° da linguagem de implementação a ser usada. Alem disso, notamos que nos últimos anos esta sendo desenvolvida muita pesquisa sobre uma geração de computadores que envolvem massivamente arquiteturas paralelas (computação concorrente), bem como sobre sistemas de comunicação de dados e engenharia (descrição) de protocolos. O objetivo principal desta tese a dar uma resposta a estes três assuntos integrando três conceitos básicos da Engenharia de Software: Especificação Algébrica, Orientação a Objetos e Especificação de Processos e Concorrência, em uma Única abordagem expressa através de uma Linguagem de Especificação Formal, chamada LOP. Esta linguagem a de natureza algébrica, com destaque para a semântica baseada em teorias em lógica de primeira ordem e na construção incremental de especificações baseada em bibliotecas. / The abstract specification of data types, one of the most important concepts accepted and understood of the Computer Science, allows to describe the the main entities of a based-computer system through the properties that these entities should be to satisfy. This is made using algebraic methods and languages, where the properties are defined as axioms (equations). By other hand, the technology called Object-Oriented (00), it has been transformed in a mature discipline for Design and Implementations of software applications. At present, this technology include many methodologies and many languages for the totality of the system development process. But the majority are influenced by the implementation of such systems, i.e., the basic concepts 00 of class, object and inheritance are defined in accordance with the programming language to be used. Moreover, we noted that the last years are being developed many research on a computer generation that involve massively parallel architectures (concurrent computing) as well as on data communication systems and protocol engineering (description). The main objective of this thesis is to give an answer to these three subjects integrating three basic concepts of Software Engineering: Algebraic Specification, Object Orientation and Processes and Concurrency specification, in an unique approach expressed through a language of formal specification, called LOP. This language has algebraic nature with prominence to the semantics based on theories in first-order logic with equality and the incremental construction of library-based specifications.

With safety critical software, it is important that the application is safe and stable. While this software can be quality tested with manual testing, automated testing has the potential to catch errors that manual testing will not. In addition there is also the possibility to save time and cost by automating the testing process. This matters when it comes to avionics components, as much time and cost is spent testing and ensuring the software does not crash or behave faulty. This research paper will focus on exploring the usefulness of automated testing when combining it with fuzz testing. It will also focus on how to fuzzy test applications classified into DAL-classifications.

A especificação abstrata de tipos de dados, a hoje um dos conceitos mais importantes, aceitos e compreendidos da Ciência da Computação, que permite descrever as principais entidades de um sistema baseado em computador através das propriedades que tais entidades devem satisfazer. Isto a feito usando métodos e linguagens algébricos, onde as propriedades são definidas na forma de axiomas (equações). Por outro lado, a tecnologia chamada de Orientada a Objetos (00), foi se transformando em uma disciplina amadurecida para projetos e implementações de aplicações de software. Atualmente esta tecnologia inclui muitas metodologias e muitas linguagens que abrangem todo o processo de desenvolvimento de sistemas, porem, a maioria delas são influenciadas pela implementação de tais sistemas, isto e, os conceitos básicos 00 de classe, objeto e herança são definidos em fungi° da linguagem de implementação a ser usada. Alem disso, notamos que nos últimos anos esta sendo desenvolvida muita pesquisa sobre uma geração de computadores que envolvem massivamente arquiteturas paralelas (computação concorrente), bem como sobre sistemas de comunicação de dados e engenharia (descrição) de protocolos. O objetivo principal desta tese a dar uma resposta a estes três assuntos integrando três conceitos básicos da Engenharia de Software: Especificação Algébrica, Orientação a Objetos e Especificação de Processos e Concorrência, em uma Única abordagem expressa através de uma Linguagem de Especificação Formal, chamada LOP. Esta linguagem a de natureza algébrica, com destaque para a semântica baseada em teorias em lógica de primeira ordem e na construção incremental de especificações baseada em bibliotecas. / The abstract specification of data types, one of the most important concepts accepted and understood of the Computer Science, allows to describe the the main entities of a based-computer system through the properties that these entities should be to satisfy. This is made using algebraic methods and languages, where the properties are defined as axioms (equations). By other hand, the technology called Object-Oriented (00), it has been transformed in a mature discipline for Design and Implementations of software applications. At present, this technology include many methodologies and many languages for the totality of the system development process. But the majority are influenced by the implementation of such systems, i.e., the basic concepts 00 of class, object and inheritance are defined in accordance with the programming language to be used. Moreover, we noted that the last years are being developed many research on a computer generation that involve massively parallel architectures (concurrent computing) as well as on data communication systems and protocol engineering (description). The main objective of this thesis is to give an answer to these three subjects integrating three basic concepts of Software Engineering: Algebraic Specification, Object Orientation and Processes and Concurrency specification, in an unique approach expressed through a language of formal specification, called LOP. This language has algebraic nature with prominence to the semantics based on theories in first-order logic with equality and the incremental construction of library-based specifications.

Magister Educationis - MEd / The rate at which the spread of human immunodeficiency virus/auto immunodeficiency syndrome (HIV/AIDS) is increasing in the world has brought with it the realization that the disease is more complex and extensive than imagined. The alarming increase in the rate of infection combined with the fact that researchers have not found a cure has considerable socioeconomic implications. The peculiarity of HIV/AIDS, has caused almost all countries of the world to introduce different types of intervention programmes for the youth in order to reduce or eradicate the disease. South Africa, being one of the countries in the world that has the highest number of people living with HIV/AIDS, has introduced a Life Orientation Programme (LOP) into the school curriculum as a preventive measure. HIV/AIDS prevention programmes as part of the LOP are designed to increase the knowledge and skills of youths in order to adopt and maintain good sexual behaviours that can virtually eliminate the risks of becoming infected with the HIV. This study evaluates the effectiveness, efficiency, relevance and impact of LOP on the sexual behaviours of the learners in a high school in Cape Town. The study was motivated by the fact that, despite the introduction of different intervention and prevention programmes in high schools, there seems to be no significant reduction in the spread of HIV/AIDS among the youths. In order to make this evaluation worth the while, four instruments, (questionnaires, semistructured interviews, a classroom observation schedule and a test), were used in the study with the consent of the participants and the school authorities. The participants (the teachers and learners) were contacted independently by an educator who was introduced to me by the principal, so that the researcher would not influence the information provided.

Fuzzing is a test method used to automatically generate test case inputs and to executea system under test (SUT) with those inputs. The method is traditionally used to discovercrash-inducing bugs in software. Fuzzing can generate thousands of inputs per secondand many implementations use smart techniques to reach deeply into the code. Fewfuzz testing implementations, however, have the ability to explore and retain informationof state in stateful applications. We develop an extension of the fuzzer American Fuzzy Lop (AFL), building on the workof the Ijon project, and utilize its fuzzing capabilities to discover states in SUT; inparticular, applications built as finite state machines. The extension successfullyharnesses AFL’s input generation to explore the SUT’s state space. We then implement functionality that allows for the SUT to return state information tothe fuzzer, including the state path and path length. Furthermore, functionality is addedthat allows the test operator to specify the expected number of states in the SUT, andGUI extensions that provide real-time information of state discovery during fuzzing. The state information retained after a completed fuzzing session is automaticallysummarized in a structured format. We further demonstrate that the summarizedinformation can be used to generate test cases for a test operator to verify the SUT.

Apomixis, or asexual seed development, if introduced into crop species, has the potential to greatly improve global food production. Towards this goal, this study focused on uncovering the genetic mechanisms that control the parthenogenesis step within apomixis whereby fertilisation is avoided. In the model apomict, Hieracium praealtum (Asteraceae), parthenogenesis is controlled by the LOSS OF PARTHENOGENESIS (LOP) locus. Previous research showed that in addition to genomic copies of candidate genes at LOP, the genome has at least three other copies referred to as alternative alleles. The main goal of this study was to investigate four candidate genes, Genes B, X, H and Y, at LOP by generating segregation data of the alternative alleles. BAC clones containing alternative allele sequences were identified and Roche 454 pyrosequenced. These sequences were used to design alternative allele specific primers for genotyping two Hieracium praealtum polyhaploid populations (~ 300 plants). Four major conclusions were drawn from this study. First, the alternative alleles were in fact acting like alleles to the LOP alleles of Genes B, X and Y. Second, allelic sequence divergence (ASD) of the LOP alleles of Genes B and X relative to the alternative alleles, indicated a recent and separate evolutionary history. Third and, unexpectedly, recombination was detected at the LOP locus, in contrast to other apomixis loci reported in the literature. Furthermore, Gene B was found to be very closely associated with parthenogenesis in the polyhaploid population indicating that it may be essential to parthenogenesis and therefore requires further investigation. On the other hand, the absence of Genes X, Y and H, due to recombination, had no impact upon parthenogenesis. Fourth, the sequence data suggested that the LOP and alternative alleles originated from a shared common allele ancestor. It is hoped that these findings have made a significant contribution towards the future goal of introducing apomixis into crop species.