The study of the muon decay process μ+ → e+νeν ̄μ is a powerful constraint on the behaviour of the weak interaction, without contamination of the other, stronger, fundamental interactions. The spectrum measured from the momentum and angles of the decay positrons is parametrized using a set of four decay parameters. The purpose of the TWIST experiment is to measure these decay parameters to an unprecedented precision; an order of magnitude improvement in the uncertainties over measurements completed before the TWIST experiment. Measurements of the muon decay parameters constrain the values of a series of 19 weak coupling constants. In the standard model, V-A weak interaction, 18 of these constants are 0, while the remaining constant describes interactions between left handed particles, gV_LL= 1.The decay parameter ρ quantifies the behaviour of the spectrum with respect to momentum. According to the standard model the value of this parameter is 3/4. TWIST measured a value of ρ = 0.74991±0.00009(stat)±0.00028(sys). The measurement is limited by its systematic uncertainty, so a large focus of the experiment was on the determination and control of these uncertainties. The systematic uncertainties are derived from uncertainties in the detector construction and uncertainties in the biases generated by differences between the data and a matching Monte Carlo. Muon decay also limits the possibility of family symmetry breaking interactions. TWIST can be used to search for the possibility of muons decaying into a positron and a single unidentified neutral particle μ+ → e+X0 that does not otherwise interact with normal matter. The large momentum and angle acceptance of the TWIST spectrometer allows for searches of two body decays for masses of the X0 boson mX0 ∈ [0,80] MeV/c, with a variety of behaviours with respect to the angle of the positron track. Upper limits on massive and mass-less X0 decays are set with a 90% confidence level separately at parts per million for massive decays and parts in 10000 for mass-less decays.

人脈理論相關的文獻,尤以 Granovetter(1973)提出非常優雅的「弱連結 (weak tie)」一詞最為經典,他的論文發現經由弱連結介紹新工作的成功率高於 強連結,同時提出弱連結相較於強連結(strong tie)更多元,因此弱連結對宏觀世 界的效益必大於強連結。而後 Rogers(2006)也在創新的擴散中提出弱連結應 該屬於異質性連結,強連結則屬於同質性的連結,異質性不容易連結卻對擴散的 影響更大。因此本研究的動機將以弱勢的創業家為研究對象,探討弱連結擴散的 動機與擴散方法,並回答研究問題弱連結的擴散效益為何? 本研究發現弱連結的脆弱並不全然是異質性不易溝通之故,因為弱連結與強連結最大的不同是強連結靠關係遠近產生連結,弱連結則是自願性的連結居多,因此創業家的創夢才是真正點燃連結的起源,此外弱連結的橋樑特質是喜好轉介稀有性消息,產生消息經濟的效益而達到更廣泛的連結,因此研究者認為弱連結應用於創新擴散將有三點效益,第一點是弱連結因為自發性動機與可被信任的第三方而提高傳遞意願,第二點是弱連結以泛泛之交居多,他們喜好轉介稀有性消息,因此提高傳送廣度,最後發現所謂的六度分隔除了代表差異性人脈將造成平 均為六的結果外,也代表著六個人脈圈,本研究因此發現第一度的人脈差異將影 響網際網路時代的小世界接受率。 而對於創業家以弱連結來進行創新擴散,研究者認為實務上建立異質性創業 團隊將有助於進入不同特質的弱連結樞紐區,此外創業家勇於發表創夢的想法, 其心態越開放也有助於凝聚弱連結,因此創業家可以藉由社群網站或部落格等媒 體建立自行發聲的管道,將有助於幫助創業家位於樞紐中心,強化擴散的能力。 研究者在回顧文獻後也發現,弱連結在開放式網絡下的橋樑特質與效益被後來學 者忽略,同時隨著網際網路興起帶來多元的媒體與開放式人際關係,研究者認為 將更有助於觀察弱連結對創新擴散的幫助,本研究觀察 Apps 產業裡 Bonnie’s Brunch 個案後,經由八位訪談者與半年的網路社群媒體追蹤的結果,發現弱連 結的橋樑功能是資訊的聚集處,也是連結的捷徑,因此擁有對的連結的確是很重要的事,但是弱連結卻未必時常擔任善意的陌生人,因此弱連結的連結困難在於弱連結的自願性動機,因此研究者在理論貢獻部分提出弱連結的力量來源為自願性的動機,這股隱性的力量唯有受到單純動機的點燃才能爆發出來,因此創業家成功的方程式還有一項無法被操控的弱連結影響力,唯有創業家經過長期的耕耘,持續提供資訊交換,才能與弱聯結維繫關係。 / Among the personal network theory related literatures, the elegant term “weak tie” proposed by Granovetter(1973) is the most classic theory. His thesis paper finding shows that the success rate of introducing new jobs through a weak tie is higher than that of a strong tie. Hence, he believes that as the macroscopic view of the world’s weak tie is more diverse than the strong tie, the benefits produced after creating the tie are definitely greater than the strong tie. Rogers (2006) later proposed in diffusion of innovation that the weak tie is the tie of heterogeneity, while the strong tie is the tie of homogeneity. Heterogeneity does not easily produce a tie, but it has a greater impact on diffusion. Therefore, the weak tie diffusion motivation and diffusion method were explored in this study, and the research problem, i.e., the diffusion benefits of the weak tie, was answered. It was found in this study that the vulnerability of the weak tie is not entirely due to the communication difficulty of heterogeneity, because the greatest difference between the weak tie and strong tie lies in the fact that strong ties produce ties depending on the distance of a relationship, while weak ties are generally voluntary ties. Hence, entre- preneurs’ building of dreams is the actual source that triggers ties. In addition, the weak tie bridge is characterized by a preference to prefer rare news, Newsonomics, and achieve more extensive links. Thus, the researcher believes that there are three benefits when the weak tie is applied in diffusion of innovation. First, the weak tie enhances the willingness to convey messages due to its own voluntary motivation and trustworthy third party. Second, weak ties are generally formed by acquaintances. They prefer to refer rare news, thus the broader conveyance. Lastly, it was found that the so-called six degrees not only represents differential personal networks that result in the outcome of six on average, but also represents six network circles. It was therefore found in this study that the first-degree personal network will affect the small world acceptance rate in the Internet age. As for entrepreneurs, they engaged in diffusion of innovation through weak ties. The researcher believes that, in practice, the establishment of the entrepreneurial team of homogeneity is conducive to entry into weak tie hubs of different characteristics. In addition, entrepreneurs had the courage to express their ideas about building dreams, and their open-mindedness also contributed to the gathering of weak ties. Hence, it is suggested that entrepreneurs establish channels to voice themselves through communi- ty networks, BLOG, and other medias, which will help them stay in the hub and strengthen their ability to diffuse. Through literature review, the researcher found that the bridging characteristics and benefits of the weak tie in the open-type network had been neglected by subsequent researchers. At the same time, the rise of the Internet has brought about a diversity of media and open-type interpersonal relationships, which is believed to be more helpful for weak ties to contribute to diffusion of innovation. Through observations made on the entrepreneurs of Bonnie’s Brunch in the App industry, the results of interviews with 8 individuals, and long-term tracking of Internet community media, it was found that the bridge of the weak tie is a gathering place of information and it is also a shortcut of ties. Therefore, having the right links is indeed important. However, the weak tie is not always willing to serve as the stranger that displays goodwill. The difficulty in linking weak ties therefore lies in the voluntary motivation of the weak tie. In the researcher’s theoretical contributions, it was mentioned that the source of the weak tie force is the voluntary motivation, and this implicit force can only explode after igniting pure mo- tive. Therefore, the successful equation still possesses the influence of the weak tie that cannot be manipulated. Only through long-term cultivation of entrepreneurs and con- tinuous provision of information exchanges to maintain the relationships with weak ties.

Mesoscopic effects in ferromagnets could be different from mesoscopic effects in normal metals. While normal metals with a short mean-free-path do not exhibit classical magnetoresistance, weakly disordered ferromagnets with a similar mean-free-path display magnetoresistance including domain wall resistance (DWR) and anisotropic magnetoresistance (AMR). Magnetoresistance could lead to novel mesoscopic effects because the wave function phase depends on the scattering potential. In this thesis, we present our measurements of mesoscopic resistance fluctuations in cobalt nanoparticles and study how the fluctuations with bias voltage, bias fingerprints, respond to magnetization-reversal processes. The resistance has been found to be very sensitive to the magnetic state of the sample. In particular, we observe significant wave-function phase shifts generated by domain walls, and it is explained by mistracking effect, where electron spins lag in orientation with respect to the moments inside the domain wall. Short dephasing length and dephasing time are found in our Co nanoparticles, which we attribute to the strong magnetocrystalline anisotropy.

Thesis (MPhil)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: This thesis considers the contribution that Karl Weick’s notion of sensemaking can make to an improved understanding of weak signals, cues, warning analysis, and software within early warning systems. Weick’s sensemaking provides a framework through which the above mentioned concepts are discussed and analysed. The concepts of weak signals, early warning systems, and Visual Analytics are investigated from within current business and formal intelligence viewpoints. Intelligence failure has been a characteristic of events such as 9/11, the recent financial crisis triggered by the collapse of Lehman Brothers, and the so-called Arab Spring. Popular methodologies such as early warning analysis, weak signal analysis and environmental scanning employed within both the business and government sphere failed to provide adequate early warning in many of these events. These failures warrant renewed attention as to what improvements can be made and how new technology can enhance early warning analysis. Chapter One is introductory and states the research question, methodology, and delimits the thesis. Chapter Two sets the scene by investigating current conceptions of the main constructs. Chapter Three explores Weick’s theory of sensemaking, and provides the analytical framework against which these concepts are then analysed in Chapter Four. The emphasis is directed towards the extent of integration of frames within the analysis phase of early warning systems and how frames may be incorporated within the theoretical foundation of Visual Analytics to enhance warning systems. The findings of this thesis suggest that Weick’s conceptualisation of sensemaking provide conceptual clarity to weak signal analysis in that Weick’s “seed” metaphor, representing the embellishment and elaboration of cues, epitomizes the progressive nature of weak signals. The importance of Weick’s notion of belief driven sensemaking, in specific the role of expectation in the elaboration of frames, and discussed and confirmed by various researchers in different study areas, is a core feature underlined in this thesis. The centrality of the act of noticing and the effect that framing and re-framing has thereon is highlighted as a primary notion in the process of not only making sense of warning signals but identifying them in the first place. This ties in to the valuable contribution Weick’s sensemaking makes to understanding the effect that a specification has on identifying transients and signals in the resulting visualization in Visual Analytic software. / AFRIKAANSE OPSOMMING: Hierdie tesis ondersoek hoe Karl Weick se konsep van singewing ons insig teenoor swak seine, tekens, waarskuwingsanalise en sagteware binne vroeë waarskuwingstelsels verbeter. Weick se bydrae verskaf ‘n raamwerk waarbinne hierdie konsepte geanaliseer en ondersoek kan word. Die konsep van swak seine, vroeë-waarskuwing en visuele analise word binne huidige besigheidsuitgangspunte, en die formele intelligensie arena ondersoek. Die mislukking van intelligensie is kenmerkend van gebeure soos 9/11, die onlangse finansiёle krisis wat deur die ondergang van Lehman Brothers ingelei is, en die sogenaamde “Arab Spring”. Hierdie gebeure het ‘n wêreldwye opskudding op ekonomiese en politiese vlak veroorsaak. Moderne metodologieё soos vroeë waarskuwingsanalise, swaksein-analise en omgewingsaanskouing binne regerings- en besigheidsverband het duidelik in hul doelstelling misluk om voortydig te waarsku oor hierdie gebeurtenisse. Dit is juis hierdie mislukkings wat dit noodsaaklik maak om meer aandag te skenk aan hierdie konsepte, asook nuwe tegnologie wat dit kan verbeter. Hoofstuk Een is inleidend en stel die navorsingsvraagstuk, doelwitte en afbakkening. Hoofstuk Twee lê die fondasie van die tesis deur ‘n ondersoek van die hoof konsepte. Hoofstuk Drie verskaf die teoretiese raamwerk, die van Weick se singewingsteorie, waarteen die hoof konsepte in Hoofstuk Twee ondersoek word in Hoofstuk Vier. Klem word gelê op die diepte van integrasie en die toepassing van raamwerke in die analisefase van vroeё waarskuwingstelsels en hoe dit binne die teoretiese beginsels van visuele analise geïnkorporeer word. Die bevindinge van hierdie tesis spreek die feit aan dat Weick se konsepsualisering van singewing konseptuele helderheid rakende die begrip “swakseine” verskaf. In hierdie verband verteenwoordig Weick se “saad”- metafoor die samewerking en uitbouing van seine en “padpredikante” wat die progressiewe aard van swakseine weerspieёl. Die kernbeskouing van hierdie tesis is die belangrikheid van Weick se geloofsgedrewesingewing, veral die uitkoms van die bou van raamwerke asook die bespreking hiervan deur verskeie navorsers. Die belangrikheid van die aksie om seine op te merk, en die effek wat dit op die herbeskouing van raamwerke het, asook die raaksien daarvan in die eerste plek word beklemtoon. Laasgenoemde dui ook aan tot watter mate Weick se singewingsteorie ‘n bydrae maak tot visuele analise veral in ons begrip van die gevolg wat data of inligtingspesifikasie het op die identifisering van seine en onsinnighede in visualisering binne visuele analise-sagteware.

La turbulence d'onde faible (TTF) est une théorie statistique appliquée à un ensemble d'ondes aléatoires non cohérentes et dispersives. En supposant un domaine infini et une nonlinéarité infinitésimale, une prédiction sur la cascade d'énergie entre échelles par le biais d'interactions résonantes des échelles d'injection aux échelles dissipatives est alors possible. La théorie semble souvent mise en défaut par la confrontation expérimentale pour les ondes de surface. Une explication potentielle de cette divergence entre expérience et théorie est l'aspect fortement restrictif des hypothèses nécessaires à la validité de la théorie. Nous proposons dans cette thèse d'explorer l'impact du non-respect de certaines de ces hypothèses sur les propriétés statistiques de la turbulence. Des expériences à l'interface de deux liquides non-miscibles ont été entreprises afin d'étudier l'impact de l'augmentation de la dissipation visqueuse et donc de la réduction du temps dissipatif sur la mise en place de la cascade d'énergie. Une expérience à la surface de l'eau avec un confinement progressif de la largeur de la cuve a été effectuée afin d'observer une potentielle coexistence de la turbulence discrète, dans la direction confinée, et continue, dans la direction non confinée. Une analyse expérimentale des ondes gravito-capillaires où la dispersion a été réduite a permis de mettre en lumière une transition d'un régime de TTF vers un régime contenant des structures cohérentes localisées que sont les solitons. Afin de vérifier si une telle transition peut être visible sur un système physique différent, une étude expérimentale et numérique ont été conduites sur les ondes dans une plaque élastique précontrainte. Dans ce milieu l'effet de dispersion des ondes de flexion et en compétition avec le caractère non-dispersif des ondes de tension. Nous nous intéresserons par ailleurs numériquement aux régimes faiblement et fortement non-linéaires des ondes purement non-dispersives dans la membrane. / Weak wave turbulence (WTT) is a statistical theory applied to a large number of incoherent and dispersive waves. Based on the hypothesis of small non-linearity and infinite domain the theory predicts an energy cascade from the forcing scales to the dissipative scales. The confrontation of WTT to experiment for surface waves raises many inconsistencies. The strong hypotheses on which is developed the WWT may be the explanation of such disparity between experiment and theory. The aim of this Thesis is to investigate the impact of the invalidation of some of these conditions on the statistical properties of turbulence. Experiments of interfacial waves between two non-miscible fluids with different viscosities have been carried out to characterize the effect of the increase of viscous dissipation on the energy cascade. An experiment at the surface of water with an increasing confinement of the width of the vessel has been done in order to possibly observe a co-existence between discrete turbulence and classical turbulence. An experimental study of gravity-capillary waves with a decrease of dispersion led us to the observation of a transition to a solitonic regime. In order to verify whether such a transition can be observed in a different physical system, an experimental and numerical study were conducted on the waves in a prestressed elastic plate. In this medium, the effect of dispersion of bending waves is competing with the non-dispersive aspect of stretching waves. We also studied weakly and strongly non-linear regimes of purely stretching waves in a membrane.

[pt] Esse trabalho tem como objetivo ser uma introdução ao estudo da existência e unicidade de soluções fracas para equações diferenciais parciais elípticas. Começamos definindo o espaço de Sobolev para, a partir da definição, provarmos algumas propriedades básicas que nos ajudarão no estudo das equações diferenciais parciais elípticas. Finalizamos com o desenvolvimento do Teorema de Lax-Milgram e de Stampacchia que permitirão o uso de técnicas de Análise Funcional para estudarmos alguns exemplos de equações elípticas. / [en] This dissertation aims to be an introduction to the study of the existence and uniqueness of weak solutions for elliptic partial differential equations. We begin by defining the Sobolev spaces and proving some basics properties that will assist in the study of the elliptical equations. Lastly, we develop the Theorems of Lax-Milgram and Stampacchia that allow the use of Functional Analysis for the studying of some examples of elliptic equations.

Cette thèse présente une mesure de la section efficace de production du quark-top célibataire en voie t avec 1,04~fb^{-1} de données recueillies par le détecteur ATLAS au LHC à partir de collisions proton-proton d'énergie centre de masse sqrt(s) = 7TeV. Les événements sélectionnés contiennent un lepton, de l'énergie transverse manquante, et deux ou trois jets, l'un d'eux étant étiqueté comme étant issu d'un quark-b. Le modèle pour le bruit de fond se compose des processus multijets, W+jets et production de paires de quarks top ainsi que de contributions moindres venant d'événements Z+jets et diboson. En utilisant une méthode de coupures et de comptage basée sur la distribution d'un discriminant multivarié construit avec des arbres de décision stimulés, la section efficace de production de quark-top célibataire en voie t a été mesurée. La valeur sigma_ {t} = 97,3^{30,7}_{-30,2}~pb a été obtenue. Ce résultat est en bon accord avec la prédiction du Modèle Standard. En supposant que les éléments de la matrice CKM reliee au quark-top obéissent à la relation |Vtb|>>|Vts|, |V_td|, la force du couplage W-t-b est extraite de la section mesurée, |Vtb| = 1,23^{+0,20}_{-0,19}. Si on suppose que |Vtb|<1, une limite inférieure |Vtb|>0.61 est obtenue avec un niveau de confiance de 95%. / This thesis presents a measurement of the cross section of t-channel single top-quark production using 1.04~fb^{-1} data collected by the ATLAS detector at the LHC with proton-proton collision at center-of-mass sqrt(s)=7TeV. Selected events contain one lepton, missing transverse energy, and two or three jets, one of them b-tagged. The background model consists of multijets, W+jets and top-quark pair events, with smaller contributions from Z+jets and diboson events. By using a cut and count method based on the distribution of a multivariate discriminant constructed with the boosted decision trees, the cross section of t-channel single top-quark production is measured: sigma_{t}= 97.3^{+30.7}_{-30.2}~pb, which is in good agreement with the prediction of the Standard Model. Assuming that the top-quark-related CKM matrix elements obey the relation |Vtb|>>|Vts|, |V_td|, the coupling strength at the W-t-b vertex is extracted from the measured cross section, |Vtb| = 1,23^{+0,20}_{-0,19}. If it is assumed that |Vtb|<1, a lower limit of |Vtb|>0.61 is obtained at the 95% confidence level.

Context: The goal of this research is to form a correlation between code packages and test cases which is done by using automated weak mutation. The correlations formed is used as the statistical test data for selecting relevant tests from the test suite which decreases the size of the test suite and speed up the process. Objectives: In this study, we have done an investigation of existing methods for reducing the computational cost of automatic mutation testing. After the investigation, we build an open source automatic mutation tool that mutates the source code to run on the test cases of the mutated code that maps the failed test to the part of the code that was changed. The failed test cases give the correlation between the test and the source code which is collected as data for future use of the test selection. Methods: Literature review and Experimentation is chosen for this research. It was a controlled experiment done at the Swedish ICT company to mutate the camera codes and test them using the regression test suite. The camera codes provided are from the continuous integration of historical data. We have chosen experimentation as our research because as this method of research is more focused on analyzing the data and implementing a tool using historical data. A literature review is done to know what kind of mutation testing reduces the computational cost of the testing process. The implementation of this process is done by using experimentation Results: The comparative results obtained after mutating the source code with regular mutants and weak mutants we have found that regular mutants and weak mutants are compared with their correlation accuracy and we found that on regular mutation operators we got 62.1% correlation accuracy and coming to weak mutation operators we got 85% of the correlation accuracy. Conclusions: This research on experimentation to form the correlations in generating test selection statistics using automated mutation testing in the continuous integration environment for improving test cases selection in regression testing

Neste trabalho, utilizando o método espectral de Galerkin, provamos a existência de soluções fracas (quando a dimensão n é maior que 2) e existência e unicidade de soluções fracas (quando a dimensão é 2) para um sistema de equações diferenciais parciais que descrevem o movimento de um fluido quimicamente ativo em um domínio limitado em Rn, n 2≥2. / In this work, by using the spectral Galerkin method, we prove the existence of weak solutions (when the dimension n is great than 2) and existence and uniqueness of weak solutions (when the dimension is 2) for a system of partial differential equations that describes the motion of a chemical active fluid in a bounded domain in Rn, n≥2.

Esta pesquisa se propõe a compreender como a utilização das tecnologias móveis pode ser explorada para o ganho de agilidade na captação e repasse dos sinais fracos (SF) no ambiente organizacional. Os sinais fracos, apesar de, isoladamente, se apresentarem como incertos e imprecisos, se analisados sistematicamente, contém potencial estratégico relevante para as organizações. O crescente uso de tecnologias móveis e sem fio, que permeia a realidade das organizações, permite uma maior agilidade por parte das empresas, sob as perspectivas de acesso a informação, comunicação e tempo. Através da realização de estudos de caso múltiplos, contando com 10 respondentes exercendo funções multidisciplinares em diferentes organizações, buscamos relacionar essas perspectivas de agilidade provenientes da utilização das tecnologias móveis nas organizações – levantadas através de revisão bibliográfica – às etapas de captação e repasse de sinais fracos, adotadas no modelo de Inteligência Estratégica Antecipativa e Coletiva (IEAc). Com relação à captação dos sinais fracos, entende-se que o volume de informações trocado e a disponibilidade dessas informações (ambos decorrentes do uso das tecnologias de informação móveis e sem fio) podem aumentar a chance de identificação de um sinal fraco nas três perspectivas analisadas. Contudo, essa percepção dos sinais fracos é vinculada também às características do profissional, que deve assumir uma atitude proativa e atenta no sentido de perceber e interpretar essas informações. A respeito do repasse de informação, entende-se que o ganho de agilidade pelo uso das TIMS pode ser explorado, dado que a redução das barreiras geográficas permite ganhos no processo em relação ao tempo, à comunicação e ao acesso à informação. / This research aims to understand how the use of mobile technologies can be exploited to gain agility in the capture and transfer of weak signals in the organizational environment. When weak signals are analysed singly, they are uncertain and imprecise. However, when systematically analyzed, they contain relevant strategic potential for organizations. The increasing use of mobile technologies and wireless, that permeates the reality of organizations, allows greater flexibility for companies, on the prospects of access to information, communication and time. By performing multiple case studies, with 10 respondents which work in different functions and different organizations, we seek to relate these agility prospects arising from the adoption of mobile technologies in organizations - raised through literature review - to the stages of capture and transfer of weak signals, adopted in Strategic, Anticipative and Collective Intelligence. Regarding the capture of weak signals, is meant that the volume of information exchanged and the availability of this information (both resulting from TIMS) may increase the chance of identifying a weak signal in the three perspectives analyzed. However, this perception of weak signals is also linked to the characteristics of each professional, who should take a proactive and attentive attitude towards perceive and interpret this information. Regarding the transfer stage of weak signals information, is observed that the gain agility through the use of TIMS can be exploited, given that the reduction of geographical barriers allows gains over time, related to communication and access to information.