Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Herein we present a four chapter study on the ecology of a snake assemblage from the Brazilian semi-arid. The first chapter is the comparison of the efficiency of four traditional methods used to sample snakes: time-constrained search, occasional encounters by the staff, occasional encounters by thirds and pitfall traps with drift-fences. We conclude that the concomitant use of these methods is effective and complementary to determine the species richness of an area, but if the objectives are related to species abundance or assemblage structure the methods may be overlaid and the use of these methods together should be cautious. In the second chapter we present a summarized descriptive autoecology of the 22 species of snakes found in the study area. During this study most individuals were represented by Oxybelis aeneus and Philodryas nattereri. The third chapter deals with the effects of interspecific interactions on the structure of the assemblage. In this chapter we indicate, through a null model approach, the existence of dietary, spatial and temporal guilds. The dietary guild seems to be the most important niche dimension segregated by the snakes in the area. The fourth chapter is an investigation on how climate and prey availability affect the structure of the snake assemblage. We show that although there is no overall pattern of response, predictors related to temperature and prey availability are those that influence a greater number of species in the area. / Neste trabalho apresentamos em quatro capítulos um estudo sobre a ecologia das serpentes de uma assembléia do semiárido brasileiro. O primeiro capítulo versa sobre a eficiência de quatro métodos tradicionais de amostragem de serpentes: procura visual limitada por tempo, encontros ocasionais, encontros ocasionais por terceiros e armadilhas de pitfall com cercasguia. Concluímos que a utilização concomitante dos métodos é eficiente e complementar em relação à determinação da riqueza de uma área, porém se o objetivo do estudo estiver relacionado à abundância ou estrutura de assembléia, os métodos podem ser sobrepostos e a utilização em conjunto deve ser cautelosa. No segundo capítulo apresentamos de forma descritiva as características de autoecologia de cada uma das 22 espécies de serpentes que foram registradas na área de estudo. Durante este estudo a maior parte dos indivíduos foi representada pelas espécies Oxybelis aeneus e Philodryas nattereri. O terceiro capítulo versa sobre os efeitos das interações interespecíficas sobre a estruturação da assembléia. Neste capítulo evidenciamos a existência de estruturas de guildas alimentares, espaciais e temporais através de uma abordagem de modelos nulos, sendo a guilda alimentar a mais importante na segregação de nichos entre as espécies da área. No quarto capítulo investigamos como variáveis climáticas e disponibilidade de presas afetam a estruturação da assembléia de serpentes. Evidenciamos que embora não haja um padrão global de resposta, variáveis relacionadas à temperatura e disponibilidade de presas, são as que influenciam um maior número de espécies de serpentes no semiárido do Brasil.

The game of rugby has been played for over a century and yet its intricacies are still not fully understood. The key ingredient coaches are seeking is what can be added to a team’s make-up that will result in an increase in that teams level of playing success. The objective of this study is the exploration of the biomechanical aspects of movement in a rugby context specifically looking at the stages before, during and after contact. The hypothesis is that the optimal use of running lines in rugby union will lead to more successful breaches in the opposition’s defensive lines thus an increase in linebreaks will occur. In order to make a comparison based on scientific research principles, nine matches played during the 2001 season was compared with nine matches played during the 2002 season. For each match played in the 2001 and 2002 seasons the total number of linebreaks achieved in a match was calculated. In addition the total number of linebreaks achieved in the 2002 season was further subdivided into the specific categories of intervention in order to determine which intervention had the biggest impact on the total number of linebreaks achieved. By means of video footage of the matches played notational analysis was performed and information was gathered in order to gain data for further evaluation. The actions regarding the execution of the linebreaks were evaluated manually in respect of the intervention that was imposed during the coaching of the team during the 2002 season. Without exception a comparison between similar teams played during both seasons indicated that the total number of linebreaks achieved during the 2002 season was much higher than when the team competed against similar opposition during the 2001 season. The aggregate numbers indicated a significant increase in linebreaks from the 2001 to 2002 season. This conclusion was achieved by means of a simple T-test. Firstly an applied F-test test was done to determine whether the two samples had equal variances or not. Under the null hypothesis we assume that the variances of the two samples are equal, while the alternative states that the two samples have different variances. A value for the test statistic that is greater than the critical value will lead to a rejection of the null hypothesis. The test statistic was calculated and evaluated against the F (8,8) = 2.59 critical value on a 5% level of significance. The value of 15.921 is greater than the critical value of 2.95 and therefore the null hypothesis cannot be accepted, concluding that the two samples do not have equal variances. We then proceeded to test whether the 2002 average linebreaks are significantly higher than the average linebreaks achieved in the 2001 season. Under the null hypothesis the two sample averages are equal. Under the alternative, the 2002 average is higher than the 2001 average. In contrast to normal T-tests this specific test was a one-sided upper or right hand test due to the fact that we are testing whether the one average is greater and not equal to the other. Therefore, we would only reject the null hypothesis of equal sample averages if the test statistic were greater than the appropriate critical value. The calculated test statistic is 4.4827 and was evaluated against the t 0.05,9 = 1.833 critical value. Once again we cannot accept the null hypothesis. Therefore we can conclude that the average of the total linebreaks made during the 2002 season is statistically greater than the average of the total linebreaks made during the 2001 season. The results of this study therefore indicate that the new techniques incorporated into the coaching of the team in 2002 did positively influence the number of linebreaks when compared to the 2001 season. / Dissertation (MA (Human Movement Science))--University of Pretoria, 2005. / Biokinetics, Sport and Leisure Sciences / unrestricted

Pre-Charge Half Buffers (PCHB) and NULL convention Logic (NCL) are two major commercially successful Quasi-Delay Insensitive (QDI) asynchronous paradigms, which are known for their low-power performance and inherent robustness. In industry, QDI circuits are synthesized from their synchronous counterparts using custom synthesis tools. Validation of the synthesized QDI implementation is a critical design prerequisite before fabrication. At present, validation schemes are mostly extensive simulation based that are good enough to detect shallow bugs, but may fail to detect corner-case bugs. Hence, development of formal verification methods for QDI circuits have been long desired. The very few formal verification methods that exist in the related field have major limiting factors. This dissertation presents different formal verification methodologies applicable to PCHB and NCL circuits, and aims at addressing the limitations of previous verification approaches. The developed methodologies can guarantee both safety (full functional correctness) and liveness (absence of deadlock), and are demonstrated using several increasingly larger sequential and combinational PCHB and NCL circuits, along with various ISCAS benchmarks. / National Science Foundation (Grant No. CCF-1717420)

Sleep Convention Logic (SCL) is an emerging ultra-low power Quasi-Delay Insensitive (QDI) asynchronous design paradigm with enormous potential for industrial applications. Design validation is a critical concern before commercialization. Unlike other QDI paradigms, such as NULL Convention Logic (NCL) and Pre-Charge Half Buffers (PCHB), there exists no formal verification methods for SCL. In this thesis, a unified formal verification scheme for combinational as well as sequential SCL circuits is proposed based on equivalence checking, which verifies both safety and liveness. The method is demonstrated using several multipliers, MACs, and ISCAS benchmarks.

1) Dass die „mathematische Logik“ keine mathematische Logik ist, duerfte auch anderen Kritikern aufgefallen sein, dass sich aber ihre (angebliche) Logik nur ausschliesslich mit sich selbst beschaeftigt und darin ihren Selbstzweck findet, wurde in der Literatur noch nirgends herausgearbeitet und ist Hauptgegenstand dieses Aufsatzes. 2) Auch eine deutliche Kritik des semantischen und (trotz gegenteiliger Behauptung) auch syntaktischen Niveaus von Aussagen- und Praedikatenlogik mit ihren undifferenzierten und auf Buchstaben (Symbole) reduzierten „Aussagen“ (die hier vollkommen unpassend sind, da mathematische Logik mit der Arithmetik nichts gemein hat) war ueberfaellig und wird in diesem Aufsatz belegt. 3) In der Logik der Realitaet haben alle von vornherein willkuerlich als falsch erklaerte Praemissen nichts zu suchen. Warum sie bei den einzelnen Operatoren jeweils in drei von vier theoretischen Kombinationen absichtlich eingebaut werden, entbehrt jeden praktischen, aber auch theoretischen, Sinns. 4) Die hier vorzutragenden Argumente fuer eine unbegrenzt mehrwertige Logik und das bisherige bewusste Missinterpretieren der sog. Fuzzy-Logik stellen ebenfalls eine eigene und offensichtlich neue Idee dar. 5) Ausserdem werden in diesem Aufsatz die Bezeichnungen Null (0) und (vor allem) Eins (1) hinterfragt, und es wird der naheliegende Vorschlag gemacht, die Benennungen Null (0) und Eins (1) von den benebelnden, das Weiterdenken blockierenden und trotz Boole auch falschen, Begriffen „wahr“ und „falsch“ zu trennen. 6) Das Zusammensetzen von (nur zwei) Aussagen, die a) fuer die Logik keineswegs verbunden werden muessten und b) deren zwangslaeufiges Zusammengehoeren sowohl in der Praxis, als auch in der Theorie, (mit Ausnahme von dem „wenn-dann“-Operator) bei allen Operatoren stets unpassend ist, wird ebenfalls in diesem Aufsatz dargelegt. 7) Die Unsinigkeit fuer jegliche Logik, a) einige Operatoren durch leichte Variationen zu ergaenzen (z.B. V und XOR) und b) fuer diese dann teilweise abweichende Wahrheitswerte zu behaupten, wird kritisch vermerkt (und offensichtlich erstmalig bemerkt). 8) Das starre und sowohl praktisch als auch theoretisch aussagelose System in den Wahrheitstabellen usw. wird ebenfalls konstatiert. Die Tatsache, dass es sich hier lediglich um eine im Voraus festgelegte und keineswegs durchgaengig logische Skala handelt, die die Informatiker seit Shannon freundlicherweise fuer ihre „Namensgebungen“ (mit jeweils ein paar definierten Eigenschaften) nutzen (aber nicht nutzen muessten), wird kritisch dargestellt. 9) Das in diesem Aufsatz kurz angerissene Thema zum Zaehlen von Zahlen ist simpel, aber selbst entwickelt und neu. Diese Festlegung, dass sich die Elemente einer Menge den in ihrer Reihenfolge und in ihrem Abstand zueinander im Voraus festgelegten Zahlen anpassen muessen und nicht umgekehrt, macht den Blick frei fuer den u.g. Punkt 10) dieses Resuemees. 10) Durch den vorgenannten Punkt 9) werden die umfassenden Unterschiede zwischen der Mathematik und der mathematischen Logik offensichtlich, die klar belegen, dass die mathematische Logik nichts mit Mathematik zu tun hat und dass darum der Anspruch der mathematischen Logik, ein „Sonderrecht“ darauf zu haben, auf Semantik keinen Wert legen zu muessen und selbst entscheiden zu koennen, was „wahr“ und was „falsch“ ist, nach logischen Gesichtspunkten unhaltbar ist.

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Discrete event simulation is the most suitable type of simulation for analyzing a complex system where changes happen at discrete time instants. Discrete event simulation is a major experimental methodology in several scientific and engineering domains. Unfortunately, a conventional discrete event simulator cannot meet with increasing demands of computational or the structural complexities of modern systems such as peer-to-peer (P2P) systems; therefore parallel discrete event simulation has been a focus of researchers for several decades. Unfortunately, no simulator is regarded as a standard which can satisfy the demands of all kinds of applications. Thus while given a simulator yields good performance for a specific kind of applications, it may failed to be efficient for other kinds of applications. Furthermore, although technological advancements have been made in the multi-core computing hardware, none of the mainstream P2P discrete event simulators is designed to support parallel simulation that exploits multi-core architectures. The proposed HydraNetSim parallel discrete event simulator (PDES) is a step toward addressing these issues. Developing a simulator which can support very large numbers of nodes to realize a massive P2P system, and can also execute in parallel is a non-trivial task. The literature review in this thesis gives a broad overview of prevailing approaches to dealing with the tricky problems of simulating a massive, large, and rapidly changing system, and provides a foundation for adopting a suitable architecture for developing a PDES. HydraNetSim is a discrete event simulator which allows parallel simulation and exploits the capabilities of parallelization of modern computing hardware. It is based on a novel master/slave paradigm. It divides the simulation model into a number of specific slaves (a cluster of processes) considering the number of cores provided by the underlying computing hardware. Each slave can be assigned to a specific CPU on a different core. Synchronization of the slaves is achieved by proposing a variant of the classic Null-Message Algorithm (NMA) with a focus on keeping the synchronization overhead as low as possible. Furthermore, HydraNetSim provides log information for debugging purposes and introduces a new mechanism of gathering and writing simulation results to a database. The experimental results show that the sequential counterpart of HydraNetSim (SDES) takes 41.6% more time than HydraNetSim-2Slave and 23.6% than HydraNetSim-3Slave. HydraNetSim-2Slave is 1.42 times faster, consumes 1.18 times more memory, and supports 2.02 times more nodes than a sequential discrete event simulator (SDES). Whereas, HydraNetSim-3Slave executes 1.24 times faster, consumes 2.08 times more memory, and supports 3.04 times more nodes than SDES. The scaling factor of HydraNetSim is ⌈(β-1)*102.04%⌉ of the maximum numbered of nodes supported by SDES; where β is the number of slaves. / Diskret händelsesimulering är den mest passande typen av simulering för att analysera ett komplext system där förändringar sker i diskreta tidpunkter. Diskret händelsesimulering är en stor experimentell metod i flera vetenskapliga och tekniska områden. Tyvärr kan en konventionell diskret händelse simulator uppfyller inte med ökande krav på beräkningsprogram eller strukturella komplexiteten av moderna system som peer-to-peer (P2P) system, och därför parallellt diskret händelse simulering har varit ett fokus för forskare under flera årtionde. Tyvärr ingen simulator ansåg som en standard som kan uppfylla kraven på alla typer av applikationer. Så samtidigt få en simulator ger bra prestanda för en specifik typ av applikationer kan det inte vara effektivt för andra typer av applikationer. Även om tekniska framsteget har gjorts i multi-core datorhårdvara, är ingen av de vanliga P2P händelsestyrd simulatorer för att stödja parallella simulering som utnyttjar flera kärnor arkitekturer. Den föreslagna HydraNetSim parallella diskret händelse simulator (PDES) är ett steg mot att fokusera på dessa frågor. Utveckla en simulator som kan stödja ett mycket stort antal noder för att realisera en massiv P2P-system, och kan även utföra parallellt är en icke-trivial uppdrag. Litteraturstudien i denna tesen ger en bred översikt över aktuell metoder för att hantera de svåra problem som simulerar en massiv, stor och snabbt ändra system och ger en grund för att adoptera en passande struktur för att utveckla ett PDES. HydraNetSim är en diskret händelse simulator som gör det möjligt parallellt simulering och utnyttjar funktionerna i parallellisering av modern datorhårdvara. Det är baserat på en ny master / slav paradigm. Den delar simuleringsmodellen i ett antal specifika slavar (ett kluster av processer) med tanke på antalet kärnor som tillhandahålls av den underliggande datorhårdvara. Varje slav kan tilldelas en specifik CPU på en annan kärna. Synkronisering av slavarna uppnås genom att föreslå en variant av det klassiska Null-Message Algorithm (NMA) med fokus på att hålla simuleringen overhead så lågt som möjligt. Dessutom ger HydraNetSim log information för felsökning ändamål och inför en ny mekanism för att samla in och skriva simuleringar resultat till en databas. De experimentella resultaten visar att den sekventiella motsvarigheten till HydraNetSim (SDES) tar 41,6% mer tid än HydraNetSim-2Slave och 23,6% mindre än HydraNetSim-3Slave. HydraNetSim-2Slave är 1,42 gånger snabbare, förbrukar 1,18 gånger mer minne, och stöder 2.02 gånger fler noder än en sekventiell händelsestyrd simulator (SDES). I HydraNetSim-3Slave kör 1.24 gånger snabbare, förbrukar 2,08 gånger mer minne, och stöder 3,04 gånger fler noder än SDES. Skalfaktorn av HydraNetSim är ⌈(β-1)*102.04%⌉ av den maximala numrerade noder som stöds av SDES; där β är antalet slavar.

Pourquoi l'électeur, s'il sait que son vote ne sera pas pris en compte, s'attache-t-il quand même à voter blanc et nul ? Plus globalement, comment le vote blanc et nul a-t-il pu persister et même augmenter, en dépit de son absence de prise en compte dans les suffrages exprimés ? C'est à ce double questionnement qu'est consacrée cette thèse.En prenant appui sur l'analyse de 52 entretiens semi-directifs avec des électeurs ayant déjà votés blancs et nuls ainsi que sur des archives de bulletins annulés issus des scrutins présidentielles et législatifs de 2007 et 2012 (près de 16 000) et des réponses à un questionnaire diffusé en ligne (1632), notre démarche est donc d'allier le comment au pourquoi (et au « pour quoi ? ») et d'étudier le vote en acte davantage que le vote comme choix ou orientation. Le tout, en interrogeant le vote blanc et nul, non pas seulement comme un refus conjoncturel de choisir – lié essentiellement à un défaut conjoncturel de l'offre politique –, mais en mettant en évidence une autre lecture du phénomène. Plus précisément, nous abordons le vote blanc et nul comme un ensemble d'usages et significations socialement différenciés.Ainsi, dans une Partie n°1, nous étudions l'apparition de la catégorie « blanc et nul », la variation historique de ses normes (explicites et implicites) et les luttes dont sa définition a été l'objet. Le tout, pour comprendre comment une certaine définition du vote blanc et nul s'est imposée au point de faire sens commun (notamment la binarité manichéenne « blanc » versus « nul »). Dans une Partie n°2, il s'agit alors d'analyser la façon dont ce sens commun peut être l'objet de réceptions (voire de réappropriations) individuelles ou collectives – légitimes et illégitimes – par les agents sociaux. Et ce, au point de faire du vote blanc et nul une pratique aux usages pluriels, car socialement différenciés. Enfin, loin d'être réduits aux rôles de « récepteurs », des électeurs peuvent apparaître aussi comme des contributeurs dans la construction – toujours mouvante – de la définition de ce vote, au point d'en faire, par exemple, un outil d'action collective. / In France, elections since 1990's revealed a phenomenon considered for a long time as marginal by the electoral sociology : « blank and null » votes. The object of this thesis is to deconstruct some prenotions about this gesture and to propose a new approach. So, the author analyse it not only as an answer to a determined political offer but, especially, as a practice with plural uses and investments. Finally, he shows how these votes are the translation of relationships socially differentiated to politics and even to representative democracy.

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京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18042号 / 理博第3920号 / 新制||理||1566(附属図書館) / 30900 / 京都大学大学院理学研究科数学・数理解析専攻 / (主査)教授 堤 誉志雄, 教授 加藤 毅, 教授 上田 哲生 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM