· · · Institutional Repository

In the research of the territory of Liverpool, the in-between and Manchester an artefact of the Industrial Revolution appeared. The tunnels of Liverpool (the artefact) have been re-activated by the implementation of a series of interventions. These underground structures, each formed by a specific structural and spatial pattern, have the ability to add programme to above ground institutions and to re-connect urban routes. These interventions are visible by a series of new made 'artefacts': structures penetrating the surface in a surgical precision. Re-using the vacant places of the city and connecting them to the new underground interventions: The Urban Entrails.

The district of Transvaal in The Hague city is suffering a lack of sports and play facilities. In order to do something about this I designed a building for sports and play. This building gives new meaning to a poorly facilitated area of Transvaal. The building design together with the design of the public realm establish a connection with the rest of Transvaal in order to attract people to use this realm.

I worked in the Platform Technologies Group for 12 weeks, porting Darwin to the MV88F6281. The MV88F6281 is an ARMv5 compatible processor, with the custom Sheeva core at its heart. The goal of this project was to get Darwin building and booting into a full multi-user prompt.

This report will treat the use of models to predict discoloured water events. Discoloured water events happen when sediment in drinking water pipes is resuspended. This can lead to (brown coloured) sediment coming from the consumer's tap. As this is not desirable, models have been developed to predict these occurrences.

In this research an attempt was made to map the Indonesian water policy network through Social Network Analysis (SNA). Furthermore, the role of the distribution of information and knowledge in this (policy) network with respect to its’ capacity to perform well has been investigated. This research has shown that there are there are some fundamental issues at hand in Indonesian water management that cause systematic underperformance of the sector as whole. Although sector reformation has introduced several principles of integrated water resources management into the Indonesian water sector, positive results in terms of water policy and solutions remain unseen because they are limited by ineffective policy processes and water policy network in transition.

In collaboration with the Netherlands Cancer Institute/ Antoni van Leeuwenhoek Hospital (NKI-AVL), research was done on the experience of cancer patients within their hospital environment. Questioning what were the feelings, emotions, thoughts patients have in relation to the (built) environment. Out of this research which consisted of a observation, interviews with staff and a context mapping research, came data which was translated into a Patient Experience Scenario, a timeline which gives insight in the patients experience during its treatment of cancer. Out of this timeline came conclusions and design strategies which were implemented into the design of a new cancer center of around 8000 square meters in Leiden. In the end trying to build from the patients experience a improved hospital environment.

A performance comparison has been done between libswift and other P2P clients to assess whether libswift can be made the fastest P2P client currently available. A modular testing framework targeted at testing and measuring P2P clients has been developed and has been succesfully used to run several experiments with the clients and to debug and improve libswift. The results mainly compare libswift and libtorrent; uTorrent has been found unreliable under Linux and HTTPS was only used as a baseline measurement. libswift has also been compared to itself with different block sizes. Compared to libtorrent libswift performs quite well, but still suffers from two deficiencies: degrading download performance when many peers try and download the same swarm and large memory usage when confronted with very large files. libswift usually uses far fewer resources than libtorrent, though, while giving similar performance. Especially for use on mobile and other constrained devices or for joining large amounts of swarms libswift seems to be a good choice already. During the assessment several problems in libswift were identified and resolved. In particular a hard limit on the number of files libswift could handle was removed. Making libswift the fastest P2P client can certainly be done in the near future: only two deficiencies remain and libswift already shows several strong points.

This report is the result of a master thesis ofthe author, student at Delft University ofTechnology, Faculty of Civil Engineering. In this report a simulation oftests with submerged breakwaters, parallel to the shoreline, in a wave basin, are carried out with the morphodynamic model Delft2D-MOR. This 2-dimensional horizontal model was developed by DELFT HYDRAULICS. The aim of this thesis is to find out whether and how this model is able to simulate these tests with submerged breakwaters, and to investigate the effects of these breakwaters on profile development. The conditions ofthe experiments are used as input for the model. One simulation without breakwaters and two simulations with different breakwater configurations are carried out. Comparison of model results with measurement data rom the experiments shows that the model is able to simulate some hydrodynamic and morphological processes induced by the submerged breakwaters. Wave heights in the vicinity ofthe obstacles are reduced because of wave dissipation over the breakwaters. Flow circulation patterns occur induced by water level gradients. Sediment is mainly transported from behind the breakwaters towards and through the gaps seaward. However, there are still quite some differences between model and experimental results. Large amounts of sediment are eroded near the shoreline and close behind the breakwaters, which was not measured during the experiments. Apparently inaccuracies in modelling appear at the boundary of sea and land (original dry points remain dry, bottom gradients are irrealistic large), and at the location of submerged breakwaters where the modelling ofwave behaviour is not adequate. Also problems with resolution of computational grid arise at the location of submerged breakwaters. A higher resolution is needed in order to compute realistic flow velocities close behind the submerged breakwaters. Obviously a lot ofwork has to be done to improve the 2DH model results such that it can be a useful tooI for modelling the effects of submerged breakwaters on a beach profile.

The current port of the city of Nassau, the capital of the Bahamas, encounters a capacity problem for the current port. A previous study for the Bahamian Government concluded that the area of Clifton Point is most suitable for relocating the main part of the port structure. This report will focus on the feasibility of the appointed project site. With a relatively small amount of wave data, the operational and extreme conditions of the port are determined. Because the project is situated in the Caribbean, the influence of hurricanes is also included. The site conditions show that the conditions at Clifton Point are relatively calm. The next step is to determine the characteristics of the relocated vessels and cargo. Therefore a forecast is performed. With the forecast the functions of berths and terminal areas are determined. For this reason a capacity study is performed. Several alternatives are generated for the new port design. Because of the restricted availability of surface area at the project site, the alternative options are limited. The limited surface area is caused by the presence of an industrial area and the fact that the shore in front of the coastline is relatively steep. After performing a multi criteria analysis it is clearly that an inland port design is inefficient in relation to a port which is based on land reclamation. In a detailed study the configuration of the breakwaters is optimised; variant layouts are elaborated to select the best option of construction costs in relation to the occurring annual downtime. Also the manoeuvring of the vessels arriving at the new port structure has to be checked. The breakwater will also be designed in more detail. The geometry and composition of armour protection are part of this design. Also details of the structure like for example the armour layer at the head of the breakwater are determined. Finally it can be concluded that the chosen design is technically feasible. All design vessels are able to berth in a port, which provides a sufficient capacity and a safe turning basin for the navigation of the vessel.

Since waves have enormous power the design of structures to withstand this power is not easy. The history of breakwaters is one of many failures and damages. This has lead to continuously improving technology in marine construction. Over the years men made it possible to construct breakwaters with high stability against waves. The vertical breakwater is an ideal solution in deep water and in areas where the use of rubble stones is expensive or environmentally less acceptable. Furthermore a vertical breakwater with smooth vertical walls can be exposed to high wave loads, such as impulsive wave impacts. These impacts are characterised by very high pressure and a short duration time. It is believed that these impacts could well be essential to the failure of vertical breakwaters. The duration time of the wave impact is essential for the (dynamic) response of the caisson. For example if the wave impact duration is about the eigenfrequency of the vertical breakwater the response will reach a maximum, and the vertical breakwater could collapse. The objective of this graduation report is to investigate the assumption that wave impact is important with regard to failure of vertical breakwaters. Research has been carried out to investigate the time impact duration for vertical breakwaters and an analogy has been made of wave impacts with impulsive wave load on ships. Also, in order to investigate the (dynamic) response of vertical breakwater a computer model has been designed. With this model the response to the wave impact loads upon the Genoa Voltri breakwater can be estimated. The results of this graduation study is that wave impact do occur, but that the impact duration is much shorter than assumed in the past. The impact forces during these short duration result in little response of the vertical breakwater, since the impact duration is not in the range of the eigenfrequency of the vertical breakwater. It can therefore be concluded that wave impacts are not important for the stability of the Genoa Voltri breakwater.

Web based multimodal travel planners are able to generate adequate travel advises for the public transport using timetable information. These travel advises are nowadays lacking detailed pedestrian route advises for the walking parts of a journey. This research focuses on developing a 3D geo data model to support pedestrian route finding for access, change and egress public transport in multimodal travel advises. The research studies the suitability of Oracle spatial 11g to find walk routes in such geo data models. It focus on geo data models to support finding an optimal route for the individual public transport traveller taking into account his specific preferences and constrains (e.g. wheelchair) for the pedestrian part of the journey in a travel advise. Travel time and time pressure, physical effort safety and conform personnel characteristics and vicinity are seen as important aspects of an optimal route. A literature study is done on existing standards and models to investigate approaches to develop such a 3D geo data model. Based on this literature study a new conceptual geo data model is developed to support pedestrian routing in multimodal travel advises. It uses, similar as in a navigable space model (Slingsby, Raper 2008) a model representing 3D spaces only by their lower surfaces. A Stop Place Model (IFOPT 2007) is taken for it semantics describing and indentifying these spaces relevant for pedestrian routing related to public transport. To persist the geometrical aspects of these lower surfaces in a spatial database the geo data model uses simple feature (OGC 1999) surfaces. The model supports modelling of multiple layered floors and traffic areas which can be seen by a traveller on which “walking around” is possible. It also supports virtual surfaces “hidden paths” with are predefined logic connecting route areas on these floors and traffic areas. As in existing models (Lee 2004) (Stevens, Choi 2006) adjacency and connectivity of spaces are modelled with networks. The developed pedestrian model is new because attributes and behaviour of networks and surfaces are integrated. Important in this geo data model is that no difference is made between in modelling indoor and outdoor spaces. The lower surfaces representing spaces are modelled as objects inherit attributes and behaviour from nodes in a network and therefore called NodeSurfaces. Every NodeSurface is seen as possible connection for a route choice for an optimal pedestrian route. These possible pedestrian connections are modelled by combining connecting NodeSurfaces and using simple feature multiSurface to model it geometrical aspects. In this geo data model these multi surfaces are describing the potential pedestrian connections with attributes and behaviour from links in networks. Important characteristics of this multiSurface (“LinkSurfaces”) are the direction (including up/down in 3D), the accessibility and pedestrian duration for a specific traveller. A prototype implementing this new geo data model in Oracle 11g was developed. To illustrate and evaluate the new model surfaces relevant in a simple bus stop and a multimodal transport interchange where drawn in Google SketchUp and exported to KML files. These 3D surfaces where used as dataset for optimal route finding in the prototype. This research evaluates this prototype to evaluate the feasibility and suitability of the new geo data model. This prototype was also used to evaluate in suitability of Oracle spatial 11g to find walk routes in such pedestrian models. The results of the conceptual model are promising especially when modelling hidden paths. It was possible to implement the geo data model in Oracle 11g. Oracle 11g network shortest route capabilities for logical network turned out to be suitable for finding the optimal route for individual travellers with specific speed and accessibility properties. Due to the limitation that Oracle 11G does not support 3D distance calculation in geographic 3D all distances in pedestrian speed calculation were done on the geodetic surface. Optimal pedestrian routes where exported to KML files and visualisation was done with Google earth. Limitations were found for visualisation of surfaces below ground level (underpasses). The concepts of LinkSurfaces used to represent 3D pedestrian spaces in the proposed geo data models worked well in the prototype. This concept combing characteristics from links in a network and characteristic from OGC simple feature multi surfaces, is a simple, effective and well structured way to represent complex 3D spaces used by pedestrian routes in a geo data model.

In the present report field erosion tests of the inner slope of a sea dyke in the province of Groningen (near Delfzijl) are described for the situation of severe wave overtopping. Three types of tests have been performed: tests at the present grass cover, tests at a reinforced grass cover and tests at a section of bare clay. At the reinforced grass cover section a provisional Smart Grass Reinforcement (SGR) system was installed in May 2006 (Royal Haskoning & Infram, 2005). The test sections were 4 m wide and extended over about 16 m along the inner slope, down from the dyke crest. It should be remarked that the erosion tests focused on the inner slope from the crest to some distance above the level of the service road. Below the service road, the berm slope was artificially strengthened with riprap as to avoid any damage on beforehand. The tests have been carried out under the framework of ComCoast, Work Package 3 (WP3). Additional measurements have been commissioned by the SBW program (Sterkte & Belastingen Waterkeringen or in English: Strength & Loads Water Defences), a research program for improvement of knowledge of present defences. These measurements included: measurement of flow velocities and water depths, infiltration tests, determination of the soil shear strength and an additional erosion test at a bare clay section. The present report is an overall report, presenting a full overview of all test activities, as far as conducted under the responsibility of the consortium. At a later stage, the SBW measurements will be analysed further within the scope of the SBW program. Where applicable, however, some preliminary results are included in this report. For further information, the present report addresses background reports that were written within the framework of ComCoast or SBW. Special reference is made here to the report on the wave overtopping simulator (Infram & Royal Haskoning, 2007), a summary of which has been presented in the present report in Chapter 4.

We propose a minimum cost path approach to track the centerlines of the internal and external carotid arteries in multispectral MR data. User interaction is limited to the annotation of three seed points. The cost image is based on both a measure of vessel medialness and lumen intensity similarity in two MRA image sequences: Black Blood MRA and Phase Contrast MRA. After intensity inhomogeneity correction and noise reduction, the two images are aligned using affine registration. The two parameters that control the contrast of the cost image were determined in an optimization experiment on 40 training datasets. Experiments on the training datasets also showed that a cost image composed of a combination of gradient-based medialness and lumen intensity similarity increases the tracking accuracy compared to using only one of the constituents. Furthermore, centerline tracking using both MRA sequences outperformed tracking using only one of these MRA images. An independent test set of 152 images from 38 patients served to validate the technique. The centerlines of 148 images were successfully extracted using the parameters optimized on the training sets. The average mean distance to the reference standard, manually annotated centerlines, was 0.98 mm, which is comparable to the in-plane resolution. This indicates that the proposed method has a high potential to replace the manual centerline annotation.

Onderzoek in opdracht van de Stuurgroep Experimenten Volkshuisvesting