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The need for coastal structures, such as breakwaters, at great water depths is rapidly increasing as a result ofthe increasing draught of large vessels and off-shore land reclamations which can, for instance, be used for the benefit of the expansion of harbours and related industrial activities. In water depths greater than approximately 10 m vertical breakwaters may be the best alternative compared to ordinary rubble mound breakwaters, in terms of performance, total costs, environmental aspects, construction time and maintenance. However, these breakwaters with plane vertical front walls can be exposed to enormous hydraulic loads, such as wave impacts. Wave impacts are dynamical hydraulic loads with, for instance, a very short duration (in the order of magnitude of ms) and a very high peak force which can exceed the quasi-static wave load on a vertical breakwater more than 10 times. As it is described in chapter 1 "Introduction", this report contains the reflection of a research which has been performed on the effect of wave impact loads on the stability of vertical breakwaters. This Master's thesis is divided into three parts: A - Wave impact loads on vertical breakwaters In chapter 2 "Hydraulic loads on vertical breakwaters" different types of quasi-static and wave impact loads are described. Three types of wave impact loads can be distinguished depending on the amount of trapped air between the breaking wave and the plane vertical front wall of a breakwater. In chapter 3 "Wave impact pressures", chapter 4 "Wave impactforces and momentum" and chapter 5 "Special attention to wave impacts with a trapped air pocket" different formulae are presented which can be used to calculate the characteristics of wave impact loads on vertical breakwaters. In chapter 6 "Vertical breakwater design formula and wave impacts" short attention is being paid to the calculation of wave (impact) loads according to the most widely used prediction method for wave (impact) pressures on vertical breakwaters. B - Derivation of models which describe the dynamical behaviour of a vertical breakwater In chapter 7 "Derivation of an analytical mass-spring model of a vertical breakwater", in chapter 8 "Derivation ofa mass-spring-dashpot TILLY model ofthe vertical breakwater" and in chapter 9 "Analysis ofthe structure andfoundation parameters ofthe vertical breakwater" models which can be used to describe the dynamical behaviour and stability of a vertical breakwater which is exposed to wave impacts are treated. A lot of attention is being paid to the influence of the magnitude of the different dynamical properties (mass, stiffuess and damping) of such a model. C - Analysis of different types of wave impact loads on a vertical breakwater and conclusions The "Analysis ofdifferent types ofwave impact loads on a vertical breakwater" is reflected in chapter 10. "Conclusions and recommendations" can be found in chapter 11. It can be concluded that the stability of a vertical breakwater against wave impacts entirely depends on the type ofwave impact load which is to be expected (i.e. rise time, total duration, magnitude of the peak force, the amount of trapped air) and the dynamical properties of the vertical breakwater and its foundation soil (mass, stiffuess and damping). The maximum peak force of a wave impact does not necessarily induce the maximum dynamical response of a vertical breakwater. Wave impacts with relatively low peak forces and long total durations (relative to the eigenperiod(s) of a vertical breakwater, double peaked wave impact forces and wave impacts followed by low frequency force oscillations due to large trapped air pockets seem to be more dangerous for the stability of a vertical breakwater. The amount of momentum is one of the governing properties of a wave impact load concerning the response and stability of a vertical breakwater. The suggestion commonly found in the literature that wave impacts are totally not significant and should not be used for the design of vertical breakwaters could not be confirmed. A dynamical analysis of the behaviour of a vertical breakwater by means of a mass-(elastoplastic)- spring-dashpot computer model should become a necessary part ofthe design process of vertical breakwaters which are exposed to breaking wave loads. The characteristics ofthe wave impact loads to be expected and the foundation characteristics should be obtained form large scale hydraulic model tests and site investigations.

BMW envisions a future where cars will drive on their own without humans needing to control it. This will change the way people are sitting in their cars, since they are able to use this time for working and relaxing. In preparation to this development, the company is now interested in the design of a back seat where the passengers can relax, play and work as they will do in the front seat of the future. Within this project, a seat was designed for the aforementioned scenario. User research has played an important role during the development of the new seat concept. First, to determine key points for the design during the analysis phase and later in the process to evaluate the proposed design. This report consists of two parts: Analysis and Design. The first part consists of a literature study (evaluating the current situation concerning car seating, activities and comfort) and a report of the user research on behavior while using handheld devices in a car. This literature study and user research provide with key points for design: problems that can be solved and desires that can be met with a new design of a back seat. The second part of the report starts with a framework of the design by focusing on a selection of the key points. Next, a vision for the seat is established. The designed concept seat is explained in a scenario of use and a presentation of the product structure. Finally, the design is evaluated with a second user research and recommendations are developed.

The authors employ a cryogenic high electron mobility transistor (HEMT) amplifier to increase the bandwidth of a charge detection setup with a quantum point contact (QPC) charge sensor. The HEMT is operating at 1 K and the circuit has a bandwidth of 1 MHz. The noise contribution of the HEMT at high frequencies is only a few times higher than that of the QPC shot noise. The authors use this setup to monitor single-electron tunneling to and from an adjacent quantum dot. The authors measure fluctuations in the dot occupation as short as 400 ns, 20 times faster than in previous work.

In a business world where innovation is the main competitive advantage for a company, facilitating and improving the creativity of employees is of paramount importance. This graduation thesis, executed at Logica, comprises the report of a product design which can contribute to a more inspiring working environment. For this project the interaction centred design methodology Vision in Product design (ViP) was used. To gain insight into inspiration, creativity at work and the influence of office design, a literature study has been conducted. The most important findings are that inspiration is needed for continuing creativity, being inspired is a competence which one can develop and that it is a highly personal construct which requires deliberation and planning. The current trend in office environments is that of “smart working” which makes use of flexible work environments, which are aimed at collaboration and making optimal use of floor space. Employees do not have owned work stations anymore, which means there is little to no opportunity to personalize the working environment to fit the needs and wants of the individual. By means of a focus group the target user was involved in the design process. It was confirmed that employees felt limited due to the impersonal nature of the flexible working environment. Employees expressed they first need to feel comfortable and at home before they can be inspired. As the standardized office environment is experienced as highly impersonal, the need for personalization was identified. Furthermore, it was found that employees in a technical working environment are often unaware that the work they are doing requires a lot of creativity and as an effect; they do not spend time and effort to inspire themselves. The starting point for the development of a product proposal is the design vision. Using the information from the analysis, factors are formulated. Evaluating these factors results in the distinction of the following clusters: inspiration state, inspired by, managing inspiration, territoriality, office nomads and paradox of work, which make up the context vision. The goal for the project is formulated in the following design vision: “I want knowledge workers to learn that they can inspire themselves, by allowing them to shape their own working environment.” Inspired by the metaphor of Guerrilla Gardening the following qualities have been drawn up to describe the new interaction between the user and the office environment: deliberated response, customized effort, inspiring transformation and exploring freedom. The concept development has led to a personal virtual extension of the flexible work station for use in the Logica office environment. The selected concept proposal uses a DLP projector linked to an online profile to display personalized visualisations on privacy screens. It allows the user to quickly personalize the flexible work station with his or her sources of inspiration. Furthermore it promotes an engaged attitude towards the office environment and inspiration as a personal construct. For the proof of concept a user test with a mock-up is performed. Six Logica employees participated and performed their daily work activities at a personalized work station. They were asked to quantify their feeling of inspiration. In the end, all six participants felt more inspired while working on the modified work station. Concluding, the product is evaluated based on knowledge from the analysis phase and the design vision. Overall it can be said that the application of personalized projections in the office environment offers high potential. It gives the user an opportunity to virtually create an inspiring work environment in a setting where the possibilities for physical modifications are limited.

Riding a bicycle is common for many people. Bicycle ergonomics on the other hand are less common for most of use, while it is very important for the overall experience of the bicycle. The knowledge of these ergonomics ends with frame size and saddle height. Santos, a Dutch bicycle manufacturer, strives for high quality bicycles and therefore acknowledges the importance of bicycle ergonomics. They pointed out the opportunities within the field of the bicycle handlebars to support ergonomics and differentiate from competitors. Goals of the graduation project is to come up with an ergonomics set of handlebars that match the different bicycles sold by Santos and fits the ‘custom build’ philosophy at the same time. Bicycle ergonomics In the literature bicycle ergonomics are categorized in two main groups; posture height and posture length. The first, poster height, describe the bicycle variables that are related to the lower extremities and lower back. Most important variable within the posture height is the position of the saddle. The posture length describes the variables related to the back, neck and upper extremities, with the position of the handlebar as most important variable. In this theory ‘position of the handlebar’ actual means the position of the grips, since these determine the position of the hands and thereby the position of the arms and the upper body. Handlebar ergonomics Handlebars are minimized elements of the bicycle that serve maximal purpose. Of course they are used for steering the bicycle, but at the same time the handlebar houses many other elements like break handles and shifters. Most important is that they determine the position of the grips. This aspect determines the overall shape of the product, but how is this position determined. Essential is that the suite the so called neutral position on the arm and wrist. The two most common non-traumatic overuse injuries in cycling are Carpal Tunnel Syndrome (CTS) and Ulnar Nerve Syndrome (UCT), both are the result of nerve compression in the hands, wrist or forearm. These injuries come from repetitive movements, vibrations, extreme hand positions or direct pressure to the carpal or ulnar nerves. The risk to these overuse injuries can be minimized by the neutral wrist position (7°-9° extension, 5°-7° ulnar deviation and 30° pronation from the thumb up position). Knowing the neutral positions does not automatically lead to just one handlebar that is the ergonomic solution, because the cycling posture depends from the purpose of cycling. An MTB asks for a different posture than a city bicycle. All information is concluded in a graph that shows grip positions for different purposes of cycling. The gathered insights in ergonomics are translated to four handlebars that fit the Santos portfolio. The S-6, T-18 and T-38 fulfill the theory of ergonomics, where the M-10 is a variation to the S-6 that increases the grip angle without changing the overall cycling posture. Adjustable bar-ends The literature points out that, in endurance cycling, it is important to change hand positions to bring back static pressure and to minimize the risk on CTS and UCT. Bar-ends are a useful addition to normal handlebars for a second or even third hand position. However, normal bar-ends form a set angle with the handlebars. As an extension of the ergonomic handlebars, a set of adjustable bar-ends are developed to create an optimal second hand position for each individual.

We propose and implement a nondestructive measurement that distinguishes between two-electron spin states in a quantum dot. In contrast to earlier experiments with quantum dots, the spins are left behind in the state corresponding to the measurement outcome. By measuring the spin states twice within a time shorter than the relaxation time T1, correlations between the outcomes of consecutive measurements are observed. They disappear as the wait time between measurements becomes comparable to T1. The correlation between the postmeasurement state and the measurement outcome is measured to be ~90% on average.

We show that an insulated electrostatic gate can be used to strongly suppress ubiquitous background charge noise in Schottky-gated GaAs=AlGaAs devices. Via a 2D self-consistent simulation of the conduction band profile we show that this observation can be explained by reduced leakage of electrons from the Schottky gates into the semiconductor through the Schottky barrier, consistent with the effect of ‘‘bias cooling.’’ Upon noise reduction, the noise power spectrum generally changes from Lorentzian to 1/f type. By comparing wafers with different Al content, we exclude that DX centers play a dominant role in the charge noise.

We observe multiple stable states of nuclear polarization and nuclear self-tuning over a large range of fields in a double quantum dot under conditions of electron spin resonance. The observations can be understood within an elaborated theoretical rate equation model for the polarization in each of the dots, in the limit of strong driving. This model also captures unusual features of the data, such as fast switching and a ‘‘wrong’’ sign of polarization. The results reported enable applications of this polarization effect, including accurate manipulation and control of nuclear fields.

Besides an electric charge, electrons also have a tiny magnetic moment, called spin. In a magnetic field, the spin has two possible orientations: 'spin-up' (parallel to the field) and 'spin-down' (anti-parallel to the field) and can therefore be used as a quantum bit, the computational unit of a quantum computer. For quantum computations, quantum bits must have long relaxation and coherence times. Furthermore, one needs to be able to manipulate and read out the quantum bits. The research in this thesis aims at developing a solid-state quantum bit using electron spins, confined in quantum dots. We perform single-shot read-out of electron spin states and observe long relaxation times. These measurements also reveal that lattice vibrations (phonons) play a dominant role in the spin relaxation process. To increase the spin read-out fidelity we introduce a novel approach to ultrafast charge detection: a high electron mobility transistor operated as a cryogenic pre-amplification stage. Another essential requirement is the ability to coherently manipulate the electron spin, which we achieve by generating an oscillating magnetic field close to the dot. We also use this electron spin resonance technique to indirectly control the surrounding nuclear spins. This electron-nuclear interaction might be used to prepare a nuclear spin environment where fluctuations are reduced.

In the current study the relationship between objective measurements and subjective experienced comfort and discomfort in using hand saws was examined. 12 carpenters evaluated five different hand saws. Objective measures of contact pressure (average pressure, pressure area and P-t integral) in static and dynamic conditions, muscle activity (EMG) of five muscles of the upper extremity, and productivity were obtained during a sawing task. Subjective comfort and discomfort were assessed using the Comfort Questionnaire for Hand tools and a scale for Local Perceived Discomfort (LPD). We did not find any relationship between muscle activity and comfort or discomfort. The P-t integral during the static measurement (beta=–0.24, p<.01) was the best predictor of comfort and the pressure area during static measurement was the best predictor of local perceived discomfort (beta=0.45, p<.01). Additionally, productivity was highly correlated to comfort (beta=0.31, p<.01) and discomfort (beta=–0.49, p<.01).

2e druk 1981 Uitgegeven in opdracht van: Vereniging voor Studie- en Studentenbelangen te Delft. Dit boek behandelt de "klassieke schakeltechniek" en is in de eerste plaats bestemd voor degenen die zich beroepshalve met het ontwerp en van digitale apparatuur (gaan) bezighouden. Het niveau is afgestemd op H.T.S.-student en en studenten van de T.H.'s in de eerste jaren van hun studie. Veel aandacht is besteed aan de didactische opbouw van de stof, zodat het boek ook geschikt is voor zelfstudie. De behandeling van de diverse onderwerpen is elementair en vergt behalve een geringe kennis van de elektronica vrijwel geen voorkennis van andere vakgebieden. Om praktische redenen is afgezien van een vertaling van de ingeburgerde Engelse termen. In een vakgebied, dat zo sterk beheerst wordt door en berust op Engelstalige literatuur en handboeken, zou dit de toegankelijkheid van de internationale literatuur slechts schaden. Enige basiskennis van de Engelse taal is daarom gewenst, maar niet nood zakelijk. Voor die termen waarvoor een Nederlandse uitdrukking bestaat is deze in de tekst genoemd. De behandelde stof biedt de noodzakelijke basiskennis om een cursus "microprocessoren" of "computerarchitectuur" met succes te kunnen volgen. Een belangrijk deel van deze stof vindt men in de hoofdstukken over besturingen en organisatie van digitale schakelingen in het tweede deel. De in deze hoofdstukken gepresenteerde stof is basiskennis voor het ontwerpen van logische schakelingen met bit-slice microprocessoren. Bij deze bouwstenen heeft men meer vrijheid in de structuur van een ontwerp dan bij de standaard microprocessoren.

This report describes the application of the BioChem-DSS, being developed in the EU KP6-programme AquaTerra, BASIN R3 work package, with the aim to assist in the definition and improvement of management options for the Meuse region. A case study was carried out in a flood plain site of the river Dommel, a tributary to the Meuse. The present T0-situation was established, and the chemical and toxicological effects of sedimentation resulting from flooding events were investigated. In the T1 scenario, the sedimentation of 10 cm of Dommel sediment was simulated. The quality of the suspended solids in the Dommel is very poor. As, Cd, Cu, Ni, Pb, Zn concentrations all exceed the quality standards for soil ("Intervention value") by some factors. In the T2 scenario, sedimentation was simulated when the metal load of the Eindergatloop, discharging into the Dommel, would be reduced to zero. Plant uptake did not differ much between scenarios, which was expected because the deposited layer is too small to achieve physical contact between the sediment and the roots of most plants. For monocotyls however, some differences occur. Internal contents of the shoots are doubled from 0.15 mg/kg dw in the T0-scenario to 0.31 mg/kg dw in the T1-scenario. Grasses are a preferred food category for most herbivores, and may therefore impose a significant contribution to the dietary uptake of cadmium. Cadmium and zinc are effectively accumulated by willow. Dicotyls take up copper in larger amounts. It is apparent that actual risks at the Borkel site depend on the type of land use and habitat, and key species that may occur or are foreseen in future redevelopment situations. The largest body concentrations for invertebrates will occur with scenario T1. Metal accumulation is a factor 2 (Cd, worm) to 7 (Zn, isopod) larger than in the present T0 situation. For the T2 scenario, body concentrations are lower than for the T1 scenario, but are still elevated in comparison to the present T0 situation.

Bij de aanleg van overstromingsgebieden in rivier- of beekdalen, met als doel het vergroten van de waterbergingscapaciteit, loopt de waterbeheerder vaak tegen het probleem aan dat de bodemkwaliteit van de overstroomde gebieden wordt beïnvloed door de kwaliteit van zwevend stof (in dit project is gefocusseerd op het gehalte aan zware metalen). Dit materiaal bevindt zich in suspensie bij de stromingscondities die heersen in de rivier zelf, maar sedimenteert bij de zeer lage stroomsnelheden die optreden in de geïnundeerde gebieden. Dit verklaart de beïnvloeding van de bodemkwaliteit. De bodemkwaliteit langs de oevers van de rivier is ook van invloed op de realiseerbaarheid van diverse typen landgebruik. Dit geldt zowel voor het behalen van natuurdoelstellingen als voor agrarische gebruiksmogelijkheden. Mede gezien het mogelijke optreden van planschade is er voor het plannen van beheersmaatregelen (op een tijdschaal van enkele tientallen jaren) behoefte aan meer inzicht in de invloed van inundatieduur en inundatiefrequentie op de mate van verontreiniging, de ruimtelijke verdeling daarvan en de risico’s voor mens en dier die daarmee gepaard gaan. In dit onderzoek is daarom bekeken wat de effecten van overstroming met verschillende frequentie en duur zijn op depositie van vervuild zwevend slib en wat dit betekent voor de bodemkwaliteit op verschillende punten in het overstromingsgebied. Als locatie is gekozen voor een gebied langs de Dommel, ten zuiden van Valkenswaard. Er is gebruik gemaakt van bestaande gegevens over de water- en bodemkwaliteit en er zijn aanvullende metingen gedaan. Daarnaast zijn er simulaties uitgevoerd met de hydrologische modellen SOBEK 2D en CAESAR / TRACER. Beide modellen zijn met elkaar vergeleken wat betreft bruikbaarheid en complementariteit.

Due to rising costs and an increasing demand for health care services Dutch hospitals are looking for ways to reduce costs while maintaining or increasing the level of patient satisfaction. Reducing variation in bed occupation in common nursing wards could save costs by reducing the amount of required beds and nurse staffing, and increase quality of care by stabilizing the nurse workload. Adjusting current OR schedules offers potential to reduce variation because they have often been developed without explicit consideration for the wards due to the uncertain relationship between them. The main research question is therefor ’How can the management of Dutch hospitals implement adjustments to the operating room schedule in order to reduce the variability of bed occupancy in the patient wards?’. The variability in bed occupation can be seen over years, weeks and days. The weekly variation can be influenced by making adjustments to the master surgical schedule (MSS), a repetitive two weekly schedule that assigns all avail- able OR blocks to a surgical specialism. An OR block is a morning or afternoon session in a certain OR on a certain day. Analysis has shown that for the Sophia hospital, which is used as a case study in this research, only 16% of total admis- sions should be considered because they can be directly influenced by adjusting MSS. Research has shown this group exhibits the most variation. Swapping OR blocks in the MSS is difficult because analysis revealed the MSS was not as repetitive as thought and differed slightly each cycle due to for example specialisms trading or cancelling blocks. To solve this the MSS was reconstructed using historical data over an entire year to find for each block which surgical specialism has used the block the most cycles for elective surgeries. The resulting reconstructed MSS represents the structural influence the MSS has had over that year. This reconstructed MSS can be adjusted by swapping MSS blocks in order to reduce the structural bi-weekly variation caused by the MSS. This variation can be seen in wards, specialism clusters, wings and the entire hospital. This research will focus on making adjustments to the structural master surgical schedule that reduces bi-weekly variation in common wards per surgical specialism cluster. Current literature has a low rate of implementation because the influence of stakeholders is often disregarded, and rarely sees the MSS as a tool to level ward occupancies. Optimization approaches are limited because an optimal MSS is an unobtainable objective given the variety of objectives of stakeholders. This thesis presents a visualization allowing non-technical users to identify beneficial MSS block swaps between blocks from within a single surgical specialism cluster. A decision support tool (DSS) allows stakeholders to quickly evaluate the effect of those swaps on variability in their bed occupation in nursing wards. The DSS does this by adapting an implementation of the mathematical model from van Berkel that is able to relate the master surgical ward to the occupation in the nursing wards. The DSS is able to predict the effect of the structural MSS accurately enough to evaluate changes in structural variation patterns caused by MSS block swaps. Experimentation has shown the method is able to identify a potential reduction in peak occupation by several beds for both the neurosurgery- and common surgery cluster in Isala. Another observation was that an unequal division of MSS blocks over the week caused peaks in occupation that could not be compensated with MSS block swaps. This led to the suggestion of a multi- stage approach to bed leveling through the MSS, where the division over the week of MSS blocks from a specialism cluster or hospital wing is equalized as much as possible. MSS block swaps can then be done between clusters or wings (discussed in appendix D.1), after which swaps within clusters or wings can be applied. The developed decision support tool helps stakeholders with this last step and enables specialisms to find beneficial swaps themselves. The research is supplemented with a process design that addresses how to use and embed research efforts in a hospital environment with a strong influence of stakeholders with conflicting interests. The decision support tool can benefit a hospital looking to realise a certain reduction in peak bed occupancy in order to reduce the amount of beds. The DSS can also support a sustainable process solution with incremental adjustments to the MSS, in order to allow hospital to consider ward occupation when adjusting the MSS. This thesis has not answered the entire scope of the main research ques- tion but has identified a range of possible measures, intervention levels and a multi-stage approach to bed leveling. The method provides practical means to reduce bi-weekly variation in Dutch common nursing wards through the master surgical schedule while accounting for the influence of stakeholders. The results have yielded valuable insights for Isala, where the research will be applied and developed further. Bed leveling is not only an important issue in Isala but also becoming increasingly important in other Dutch hospitals looking to better uti- lize their expensive resources. This research has contributed to the academic field with a unique non-optimization approach to adjusting the MSS in order to reduce variation in bed occupation. Contrary to other research the method takes into account the influence of stakeholders by enabling stakeholder inter- action to find adjustments to the MSS. In conclusion, the developed method might benefit the rapidly evolving Dutch health care sector that is pressured to improve its cost-effectiveness.