Les logiciels Flux sont des logiciels de modélisation des phénomènes électromagnétiques par la méthode des éléments finis. Ils sont particuliérement bien adaptés pour l'analyse fine des machines électriques tournantes. Cependant leur interface généraliste rend la définition d'un calcul assez longue ce qui limite leur utilisation. Les travaux présentés proposent de faire une analyse du métier de la conception des machines tournantes, de manière à définir et réaliser un nouveau logiciel dédié, basé sur les capacités de calcul de Flux . En capitalisant un certains nombre de concepts métier comme des topologies de moteur ou des méthodes d'analyses classiques, ce logiciel donne un accès plus simple et plus rapide aux outils numériques dans le processus de conception des moteurs. De plus, les concepts informatiques utilisés ont permis l'élaboration d'une méthodologie de personnalisation du logiciel Flux réutilisable pour d'autre métiers et accessible à un utilisateur avancé.

<p>En av Glimek AB:s mest förekommande maskiner är SD-180 som används för degavvägning. Den finns i flera olika varianter. Den enklaste har enbart start- och stoppknapp och en potentiometer för att ställa hastigheten och en mer avancerad variant har en operatörspanel där olika möjligheter till inställningar finns.</p><p>Konstruktionen på denna maskin hade inte uppdaterats på många år och behövde en uppdatering av användargränssnitt, programvara och elkonstruktion. Arbetet har framförallt koncentrerat sig på användargränssnittet till panelen.</p><p>En del av arbetet var att undersöka om det var möjligt att utesluta PLC ur konstruktionen och använda en mer avancerad programmerbar frekvensomformare. Eftersom det blev problem med lanseringen av programvara till frekvensomformaren och enbart en mindre bra fungerande demoversion fanns tillgänglig så var detta tyvärr inte möjligt.</p><p>I arbetet har olika varianter på operatörspaneler utretts. Exempel på flödesdiagram till PLC har också gjorts.</p> / <p>One of Glimek AB's most common machines is the dough divider, SD-180. It is available in many different variants. The simplest has only a start- and stop button and a potentiometer to set the speed. A more advanced version has an operator panel with various options.</p><p>The design of this machine had not been updated in many years and needed an update of the user interface, software and electrical construction. The thesis has mainly concentrated on the human machine interface.</p><p>A part of the work was to investigate whether it was possible to exclude the PLC from the design and use a more powerful and programmable frequency inverter.Unfortunately problems arose with the release of the software for the frequency converter. Only a demo version of the software where available and it was not possible to this study because of that.</p><p>Different variants of human machine interface have been investigated. An example flowchart diagram to the PLC has also been made.</p>

This dissertation is concerned with finite state machine-based technology for modeling natural language. Finite-state machines have proven to be efficient computational devices in modeling natural language phenomena in morphology and phonology. Because of their mathematical closure properties, finite-state machines can be manipulated and combined in many flexible ways that closely resemble formalisms used in different areas of linguistics to describe natural language. The use of finite-state transducers in constructing natural language parsers and generators has proven to be a versatile approach to describing phonological alternation, morphological constraints and morphotactics, and syntactic phenomena on the phrase level.The main contributions of this dissertation are the development of a new model of multitape automata, the development of a new logic formalism that can substitute for regular expressions in constructing complex automata, and adaptations of these techniques to solving classical construction problems relating to finite-state transducers, such as modeling reduplication and complex phonological replacement rules.The multitape model presented here goes hand-in-hand with the logic formalism, the latter being a necessary step to constructing the former. These multitape automata can then be used to create entire morphological and phonological grammars, and can also serve as a neutral intermediate tool to ease the construction of automata for other purposes.The construction of large-scale finite-state models for natural language grammars is a very delicate process. Making any solution practicable requires great care in the efficient implementation of low-level tasks such as converting regular expressions, logical statements, sets of constraints, and replacement rules to automata or finite transducers. To support the overall endeavor of showing the practicability of the logical and multitape extensions proposed in this thesis, a detailed treatment of efficient implementation of finite-state construction algorithms for natural language purposes is also presented.

Saugos problemos virtualizuotose aplinkose tampa vis aktualesnės, todėl darbe nagrinėjama piktavališkos programinės įrangos virtualių mašinų aplinkoje aptikimo problematika. Darbe pateikiama: 1)piktavališkos programinės įrangos veikiančios virtualizuotose aplinkose analizė 2)metodikos, piktavališkos programinės įrangos virtualių mašinų aplinkoje aptikimui, sudarymas 3)piktavališkos programinės įrangos virtualioje mašinoje aptikimo, panaudojant sudaryta metodiką, eksperimento rezultatai ir jų priklausomybė nuo virtualios mašinos darbinės atminties dydžio. / In the context of virtual environment, The Security problems are highly important. The work presents analysis of malware types and it‘s presence in virtualized environments. Work also presents some results of experiments that have been carried out within the real virtual machine environment through modeling aiming to identify dependencies between the malware type, called Rootkits, detection time and the virtual machine memory size. Rootkits exploit kernel vulnerabilities and gain privileges (popularity) within any system, virtual or not. The basic result of the work is as follows: 1) the malware detection methodology for the virtual environment when the memory size of a virtual machine is changing; 2) dependences between the virtual machine memory size and Rootkit detection time.

As the major electricity consumer, electrical machines play a key role for global energy savings. Machine manufacturers put considerable efforts into the development of more efficient electrical machines for loss reduction and higher power density achievements. A consolidated knowledge of the occurring losses in electrical machines is a basic requirement for efficiency improvements. This thesis deals with iron losses in electrical machines. The major focus is on the influences of the stator core magnetic material due to the machine manufacturing process, temperature influences, and the impact of inverter operation. The first part of the thesis gives an overview of typical losses in electrical machines, with focus put on iron losses. Typical models for predicting iron losses in magnetic materials are presented in a comprehensive literature study. A broad comparison of magnetic materials and the introduction of a new material selection tool conclude this part. Next to the typically used silicon-iron lamination alloys for electrical machines, this thesis investigates also cobalt-iron and nickel-iron lamination sheets. These materials have superior magnetic properties in terms of saturation magnetization and hysteresis losses compared to silicon-iron alloys. The second and major part of the thesis introduces the developed measurement system of this project and presents experimental iron loss investigations. Influences due to machine manufacturing changes are studied, including punching, stacking and welding effects. Furthermore, the effect of pulse-width modulation schemes on the iron losses and machine performance is examined experimentally and with finite-element method simulations. For nickel-iron lamination sheets, a special focus is put on the temperature dependency, since the magnetic characteristics and iron losses change considerably with increasing temperature. Furthermore, thermal stress-relief processes (annealing) are examined for cobalt-iron and nickel-iron alloys by magnetic measurements and microscopic analysis. A thermal method for local iron loss measurements is presented in the last part of the thesis, together with experimental validation on an outer-rotor permanent magnet synchronous machine. / <p>QC 20140516</p>

M. Tech. (Information Technology, Faculty of Applied and Computer Sciences) Vaal University of Technology / The majority of research studies completed on podcasting technology focused on the acceptance of podcasting technology in the educational settings and the challenges that it poses for higher education institutions and instructors. Very little interest has been accorded to the effect that podcasting could have on the learners‟ academic performance. Utilizing a quasi-experimental non-equivalent group posttest, a wide used research method in the education discipline, the relationship between podcasting technology and academic performance, is investigated. The quasi-experimental was performed based on data collected over a period of 12 months, in which a non-random sample of 150 learners was taken from a population group of 350 management and entrepreneurship undergraduate learners at the Tshwane University of Technology. The sample was separated into two groups, namely the experimental group of 75 students, and the control group of 75 students. Both groups were offered the same subject by the same instructor. Control group learners are learners who have already completed the subject in the first semester before the podcasting technology was introduced in the subject. The experimental group learners are learners who have completed the subject through the support of podcasting technology. The assessment marks for four formal tests of the two groups were compared by means of a t-test to determine the effect of the intervention. The outcomes of the study showed an increase in the overall mean score of the experimental group in comparison to the mean score of the control group. The number of students obtaining distinctions also increased, compared to the control group. These considerations possibly indicate a positive relationship between the availability of podcast lectures and academic performance.

The convergence of mobile computing and cloud computing enables new mobile applications that are both resource-intensive and interactive. For these applications, end-to-end network bandwidth and latency matter greatly when cloud resources are used to augment the computational power and battery life of a mobile device. This dissertation designs and implements a new architectural element called a cloudlet, that arises from the convergence of mobile computing and cloud computing. Cloudlets represent the middle tier of a 3-tier hierarchy, mobile device — cloudlet—cloud, to achieve the right balance between cloud consolidation and network responsiveness. We first present quantitative evidence that shows cloud location can affect the performance of mobile applications and cloud consolidation. We then describe an architectural solution using cloudlets that are a seamless extension of todays cloud computing infrastructure. Finally, we define minimal functionalities that cloudlets must offer above/beyond standard cloud computing, and address corresponding technical challenges.

The problem with which this investigation is concerned is that of comparing a learning systems approach to a lecture-demonstration-rotation approach of teaching the manipulative skills of office machines.

Thermal analysis is an important topic that can affect the electrical machine performance, reliability, lifetime and efficiency. In order to predict the electrical machine thermal performance accurately, thermal analysis of electrical machines must include fluid flow modelling. One of the technologies which may be used to estimate the flow distribution and pressure losses in throughflow ventilated machines is flow network analysis, but suitable correlations that can be used to estimate the pressure losses in rotor ducts due to fluid shock is not available. The aim of this work is to investigate how the rotation affects the pressure losses in rotor ducts by performing a dimensional analysis. Apart from the additional friction loss due to the effects of rotation, other rotational pressure losses that appear in a rotor-stator system are: duct entrance loss due to fluid shock and combining flow loss at the exit of the rotor-stator gap. These losses are analysed using computational fluid dynamics (CFD) methods. The CFD simulations use the Reynolds-averaged Navier Stokes (RANS) approach. An experimental test rig is built to validate the CFD findings. The investigation showed that the CFD results are consistent with the experimental results and the rotational pressure losses correlate well with the rotation ratio (a dimensionless parameter). It shows that the rotational pressure loss generally increases with the increase in the rotation ratio. At certain operating conditions, the rotational pressure loss can contribute over 50 % of the total system loss. The investigation leads to an original set of correlations for the pressure losses in air ducts in the rotor due to fluid shock which are more suitable to be applied to fluid flow modelling of throughflow ventilated machines. Such correlations provide a significant contribution to the field of thermal modelling of electrical machines. They are incorporated into the air flow modelling tool that has been programmed in Portunus by the present author. The modelling tool can be integrated with the existing thermal modelling method, lumped-parameter thermal network (LPTN) to form a complete analytical thermal-fluid modelling method.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.