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The aim of this thesis is to calculate the primary inter-turn voltage distributions when the medium voltage single phase power transformer is subjected to a step voltage. This culculation is performed by considering the turns of the primary winding as transmission lines. In this thesis, the hybrid model, a combination of single transmission line model and multiconductor transmission line model,is used. Secondly, the interturn voltage distribution is computed for the situation when a medium voltage distribution cable is inserted between the source and the transformer. This distribution cable has to be modeled using a high frequency cable model. The cable is also considered as a transmission line.

The main focus of this thesis is the design a receiver frontend for FMCW radar applications. In these systems, the increasing requirements on detection resolution,points towards the use of higher frequencies. In view of this, frequencies at W-band are very attractive due to the otential of high spatial resolution, while chip size and antennas can be made more compact. However, to realize such a high performance FMCW radar system, a W-band high bandwidth LNA-mixer chain needs to be developed in a high-end integration technology. Key design parameters are low noise, high conversion gain and linearity, and above all a large operating bandwidth. Due to the application requirements in this project, high isolation between received signal and the down converting LO signal needs to be established. System considerations have been given in support of understanding and defining the LNA-mixer specifications.

Fractional-flow theory provides key insights into complex foam IOR displacements and acts as a benchmark for foam simulators. In some cases with mobile oil present the process can be represented as a two-phase displacement. We examine two such cases. A first-contact miscible gas flood with foam injection includes a chemical shock defining the surfactant front and a miscible shock defining the gas front. The optimal water fraction for the foam (i.e., the water fraction that gives the fastest oil recovery) maintains the gas front slightly ahead of the foam (surfactant) front. A first-contact miscible foam process with surfactant dissolved in the (supercritical) CO2 is influenced by surfactant adsorption on rock and also on partitioning of the surfactant between water and CO2. A foam with surfactant that is more soluble in the water would propagate slowly, regardless of the surfactants absolute solubility or the level of adsorption on rock. This study forms part of a larger study combining fractional-flow modeling of these processes with computer simulation. The simulations verify the results obtained with fractional-flow methods and illustrate the challenges of accurate simulation of these processes. For both cases (i.e., first-contact miscible gas flood with foam injection, and first-contact miscible foam process with surfactant dissolved in the gas phase), simulations show that, in the limit of small grid blocks, the solution converges towards the fractional-flow solution. Fractional-flow theory not only predicts the displacement in the absence of dispersion, but helps explain the effects of dispersion on the displacement. Numerical dispersion introduced by the simulator is shown to have significant effects on the outcome of the simulations. At the urfactant front, numerical dispersion can drastically change the nature of the foam front, depending on the foam model used (specifically, the effect of surfactant concentration on foam strength). A foam model where foam is abruptly created at 50% of the injected surfactant concentration mitigates the effects of this dispersion, but the velocity of the foam bank is still altered. Investigation on the influence of adsorption shows that Langmuir-type adsorption models tend to sharpen up the (dispersed) surfactant front and are the least sensitive to dispersion. At the miscible front, dispersion affects mobilities in the oil and gas phase; again, fractional-flow theory helps explain the implications for the displacement. In multiple-contact (developed) miscible displacements, simulations, with dispersion present, show a region of three-phase flow ahead of the miscible front.

In the year 1991 the Technical Advisory Commission (TAW-A4) ordered a full scale investigation on wave impacts on an asphaltic concrete revetment. The goal of the experiment was to gain insight into the mechanisms which would lead to failure, cracking of the revetment. Also the behaviour of the revetment after failure (residual strength) was studied. To gain insight in the behaviour of the revetment, strain measuring devices and pressure transducers were placed into the revetment. The measured strains were compared with calculated strains by several researchers. One of the researchers concluded there was almost no resemblance between the measured and calculated strain and recommended to perform a sensitivity analysis on the calculations. This conclusion and recommendation is what resulted into the subject of the thesis. Due to extensive testing of materials in the last fifteen years a better understanding of material behaviour is achieved. This concerns in particular the modulus of elasticity of asphaltic concrete and the modulus of subgrade reaction. This knowledge is used in the thesis to get new results, by recalculation, from the same model. To perform a sensitivity analysis a stochastic simulation is used. A choice is made for using the Monte Carlo method for simulation of the strains and the results of the simulations are compared with the measured strains. The conclusions are divided into conclusions regarding the recalculation and conclusions regarding the Monte Carlo simulation. In the recalculation a better agreement between the measured and calculated strain is obtained. The model describes the calculated dynamic strain in a good way. This is also concluded by Ruygrok, one of the researchers who also investigated this Delta flume experiment. The simulated strains calculated with the Monte Carlo method are not in agreement with the measured strains. The difference between the calculation and the measurements are assigned to the differences between the quasi-static and the dynamic strain. Another reason for the differences is that the information of the wave impacts stored in the impact factor distribution cannot be divided into time and space, which leads to a too rough approach in the simulation.It is recommended to investigate the relation between the quasi-static or dynamic strain with the total strain. If the quasi-static strain adds extra damage to the revetment this part should be taken into account when a safety assessment is performed.

In Japan, most cell phones have the capability of receiving GPS signals. Besides the cell phone there are many other devices that can keep track of GPS data, including the GPS device made by Sony. If all this GPS data is collected and organized, one could get a good overview of peoples whereabouts. That is why the goal of this project was to develop a tool that keeps track of peoples movements, share a visualization of these movements with other people and allow for other means of social interaction, such as chatting, messaging, finding other people and so on. To realize this goal we created the Sococa system. The name stems from the full name we had devised at first, Socialocalize. Additionally, the Japanese phrase 'sokoka' can be taken to mean something akin to 'over there?'. The system consists of a client part and a server part. The client program can parse and upload users' locations to a server in real time. The server has an interface which also allows other programs to upload their location data. Because the user doesnt always have an internet connection available, it is also possible to upload files with location data at a later time. This can be done on the website or with the client program. The server hosts a website on which a map with all positions of the users are shown. When a user uploads a new location to the server, this is directly updated on the map. The map also has the capability to show animated routes the user took in the past. The website has some social networking features. It is possible to create an account and add some personal information to it. It is possible to look up ones friends using the search option and add them as friend on the website. After they are added, users can chat in the global chat or send private messages to each other. To ensure the users' privacy, the user can choose to limit the availability of his location data to his friends or only to himself. The most important things the current system is lacking are full OpenId support and support for the Opensocial API. OpenId is a service which allows users to have only one account for the whole internet. This technology is supported by the website, but not by the client program. The OpenSocial API links social networking sites to each other, i.e. friends can be easily imported from one site to another. Because of the complexity of this technology, we have chosen not to implement this.

The border between a city and its surrounding landscape comes in all kinds of forms. It is hard to say if one is better than the other. But can they help in orientating in the city? The cities of Flanders all have a very vague transition to the landscape. In the past the government has always stimulated the people to move into the countryside, creating many direct roads (steenwegen) between the cities. These roads where used for ribbon development, hiding the green chambers behind it.Antwerp has an interesting location in Flanders because of the river Schelde, its harbour and its location near the Netherlands. Since 1970, the government has noted that the connections between city and landscape (which is divided by the ring road of Antwerp) should be improved for more efficient transport to the city centers. But few thought is spent on creating public space around the ring road which is attractive for slow traffic, connecting the different city parts on a lower scale. An opportunity exists for creating one Antwerp with a strong identity. The main focus point of Antwerp development nowadays is in 't Eilandje, an old harbour district in the north. This will move to the Zuidrand because of several large projects, which consist of dwellings, offices and the first bridge ever to cross the Schelde. These separated developments miss the chance to develop the whole area as one, and creating a low scale connection between city and landscape. The moving petrol industries, its increasing mobility because of the Oosterweelverbinding and the Schelde river offer opportunities for large developments and giving identity to the South of Antwerp and the city in total. The design for the structure vision of the Zuidrand focuses on creating low scale connections, accenting crossing points, keeping open space where possible and orientation on the Schelde. Transfer points between different modalities offer an efficient transportation to the city center and the landscape. Flexibility is important in the plan. This is achieved by creating building envelopes for people to build in, the possibility for people to build their own houses and using a strategic phasing plan to realize the whole or parts of the plan. The main transfer point is a crossing of all kinds of transportation: pedestrians, bicycles, cars, train and trams. It offers the opportunity for a transfer place and large public functions. A lively and pedestrian friendly place is created by placing different kinds of functions in high density on a small surface area. This makes it attractive and efficient to use public transportation systems to go to your destination and than walk to your goal. An icon along the Schelde is created, forming an example for the rest of the city to also return to the Schelde, which is the origin of the city. In this way a marking point between city and landscape arises, helping in orientating in Antwerp.

Breuken zien we natuurlijk in het dagelijks leven, maar hoe zit dat met breuken binnen breuken? De zogenaamde kettingbreuken hebben vele eigenschappen die ons kunnen verbazen. In deze presentatie behandelen we een specifiek type kettingbreuk: de Rosen Continued Fractions. Apart bekijken we het gedrag van de breuk voor even en oneven indices. En hierbij zoeken we steeds naar het kleinste interval waarvoor geldt dat de Rosen-ontwikkeling bijectief op zichzelf wordt afgebeeld. Deze afbeelding heet de natuurlijke uitbreiding. Vervolgens zit de natuurlijke uitbreiding zelf weer vol nieuwe eigenschappen, die de basis vormen voor verdere studie.

Wavelet Packet based Multi-Carrier Modulation (WPMCM) offers an alternative to the well-established OFDM as an efficient multicarrier modulation technique. It has strong advantage of being generic transmission scheme whose actual characteristics can be widely customized to fulfill several requirements and constraints of advanced communication systems. In the last decades wavelets have been favorably applied in signal and image processing fields but they just recently attracted attention of the telecommunication community. Therefore, some research questions remain to be addressed before novel WPMCM can be used in practice. One of the major concerns involves the performance of WPMCM transceivers under various synchronization errors. In this thesis we analyze the interference in WPMCM transmission caused by the carrier frequency offset, phase noise and time synchronization errors. Using standard wavelets the sensitivity of WPMCM transceivers to these errors is evaluated through simulation studies and their performances are compared and contrasted to OFDM. New wavelets are designed to alleviate the WPMCMs vulnerability to synchronization errors. Consequently, a filter design framework is built that facilitates the development of new wavelet bases according to the specific demands. In this regard the expressions for Inter Carrier Interference (ICI) and Inter Symbol Interference (ISI) in WPMCM transmission are first derived and stated as a convex optimization problem. Then an optimal filter that best handles these deleterious effects is designed and developed by means of Semi Definite Programming (SDP). Through computer simulations the performance advantage of the newly designed filter over standard wavelet filters is proven and further its performance is compared to the conventional OFDM.

In the works of Guy Debord and Asger Jorn, durnement played an essential role in the construction of art during the early stages of the SI (Situationist International). For the Situationists durnement was used to create political statements rather than art. In order to explain this topic I will start with a brief description of both Guy Debords and Asger Jorns histories prior to their union in the SI. The construction of a time line will help to illustrate the sequence of events that eventually lead up to the student revolts in 1968 in the streets of Paris and other parts of France. This thesis will be concerning the formation years of the SI, in particular the events surrounding Debord and Jorn from the late 1940's just after WWII, until about 1960 when the SI had been formed. Th e people they worked with prior to meeting each other very much defined the directions they were to take. Although their interests were very similar, the forms of expression that each of them gave to them were quite different. Debord's more theoretical and textual approach complemented Jorn's more artistic approach to finding a new form of expression and communication. Debord was a strategic man; he always thought everything through, theorizing before acting. Jorn was just the opposite and believed that the theory would get in the way of his artistic spirit; instead he would work in concentrated intervals on a project or series, only to try and understand it and theorize it afterwards. His written contribution to the art world and the SI is not to be neglected. Each of these men was in search of a world, they dreamt of it, and attempted to show what it could look like, in their joint work. More than art, their work became, or essentially was a political message. Against a changing society that induced passiveness, they attempted to stage a revolt from within. They were aware that the medium they needed to communicate their message was the same medium that was the cause of this state of mind. They experimented with new implementations for media. Jorn worked with painting and collages in search of meaning in primitive and folkart together with numerous groups and movements, many of which he initiated. Debord investigated the textual and cognitive aspects of language, coming in contact with the Lettrists Movement early in his life. These events made their awareness of the medium all the greater, combined with their theories and conception of a new world they paired up (along with others) to form the SI, which built on concepts developed by the Lettrists as well as the many artists active in the Avant-garde at the time. This paper comments on and illustrates the use of media by Guy Debord and Asger Jorn during the founding period of the Lettrist International (LI) and the Situationist International (SI). The maps they made together based on their theories of the dve, durnement and psychogeography, and in particular they way in which Fin de Copenhague (Copenhagen: 1957) and Mires (Copenhagen: 1959) have come into being.