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The Universal Transducer Interface (UTI) is a mass-produced interface circuit which can realize the functions of measuring signals of various sensors such as capacitive sensors, resistive-bridge sensors and resistive sensors. For some of the front-ends, an instrumentation amplifier, which is implemented with dynamic-element-matching (DEM) for its feedback structure, is integrated in the chip. In certain UTI modes, this amplifier is used to amplify small output signals of a resistive-bridge sensor or a single resistive sensor before it enters the applied modulator. According to customers’ complaints, the UTI doesn’t work well. This thesis describes how with systematic investigations three problems have been identified. The first one is that undesired offset is introduced by the limited common-mode rejection ability of the instrumentation amplifier. The second one is that for input common-mode voltages higher than 3.4V, the On-resistances of the applied NMOS switches that control the DEM loop, cause the system to be out of function. The third one is that the electromagnetic interference can introduces unwanted noise in the wiring of the external resistive-bridge sensor. Two dynamic-offset-canceling techniques have been proposed and one of them has been realized on board. With these techniques, the offset has been successfully reduced from up to 200μV to about 7 μV. The noise introduced by interference can be eliminated by applying proper shielding.

As an extension to the research on “Open Innovation”, this thesis, based on an empirical study of university spin-offs (USOs), intends to make some contributions to the increasing understanding of “openness”, not only for micro and small size firms, but also in another context other than U.S.. Moreover, instead of analyzing from a traditional firm-level perspective, the study approaches the topic by emphasizing the role of the firm’s external and geographical context in shaping the flows of knowledge that the firm can act on. Therefore, the following research questions are brought to the fore, aiming to shed some light on regional policy making: How does the concept of “Open Innovation” apply in the background of USOs in terms of their external contexts, to what extent are these firms open, and what factors will influence their openness? To initiate the study, the most urgent question ahead is to quantify the intangible concept of openness. Thanks to the magic of mathematics, different dimensions of openness are drawn from the literature, including external knowledge breadth, depth, capacity and diversity. External knowledge breadth indicates the number of types of information and knowledge a firm can access, while external knowledge depth is related to the tie strength between the firm and its various partners. External knowledge capacity denotes the “size” of the external knowledge pool, constructed by both breadth and depth. And external knowledge diversity is about the heterogeneity of partners’ social backgrounds in the knowledge pool, while also taking into account the spatial orientation of the firm. These dimensions are framed as “Openness Index”, and virtually constitute an external knowledge pool that firms “reside in”. Furthermore, influencing factors, basically enabling and strategic intention factors are extracted to reveal the power of influence on different characteristics of openness. Results from multiple regression analysis show that: 1) spin-offs in a less urbanized area (Trondheim instead of Delft) tend (or are forced) to be more open in diversity, so do older and larger firms; 2) although larger size firms receive more local supports, they generally have a smaller external knowledge capacity; 3) a founding team with a deep industrial experience may be reluctant to explore the capacity of external knowledge and receive supports, whereas a broader experience may lead to a higher diversity of the firm; 4) a prospector strategy (a competitive strategy that emphasizes product/service innovation and protection of that innovation) may stimulate the firm to become more open in diversity and receive more helps locally; and 5) a high ambition level of the firm generally benefits its openness both in capacity and diversity consistently. Remarkably, according to the test of hypotheses, probably the importance of “market space” has been underestimated, which may play a significant role in such a turbulent and rapid-changing environment that (high-tech) spin-offs pertain to. To move a step forward, the universal principles underlying the openness of university spin-offs were explored. The results imply that scalability does exist, particularly regarding diversity, which manifests a sub-linear scaling – a decreasing return with increasing firm size, and there is virtually a ceiling as diversity grows. This could be a practical and critical hint for policy makers or problem owners, as to promote diversity, some measures may be necessary for compensating this effect of diminishing return. The Structural Equation Modeling method, as “insurance” of multiple regression analysis, and a more convenient way to perform multivariate analysis, to check mediating, indirect effects and potential interrelations, was also adopted in the study. The importance of diversity is illustrated again, as a dominant variable among openness indices. This result is tagged into previous theories and analysis results, and may even relate to the concept of biodiversity, regarding the firm as a living organism. Finally, to answer the question posted in the beginning, the link between openness and performance of spin-offs needs to be exposed. Therefore another set of data was collected to gather the information of both employee (fte) and turnover in 2010. The growth rate, taking some form of absolute or relative growth, was calculated and used as dependent variables, with the openness indices as independent ones. The outcomes demonstrate that in the arena of openness, the highest employee growth and highest turnover growth do not fall in the same niche, but awarded to different winners – “innovators” that have a high diversity but weak and loose ties with partners, and “resource addicts” that have strong ties with partners, but low diversity, respectively. This inconsistency illustrates that a strategy blindly targeting at openness is neither wise nor beneficial, or even harmful. Hopefully, the analyses of this specific dataset can change some mindsets of the policy makers, especially the regional governments. They can see that: 1) tailor-made policy is preferable for either spin-offs in different stages of development, or the different players in openness arena, while a uniform approach may be more appropriate after certain (developmental) threshold; 2) the differences in entrepreneurs’ profile can be used as selection criteria, and supporting science-based firms can strongly stimulate job creation; 3) supporting policy can be developed more efficiently by benchmarking to find out the most needed and most lack-of supports currently; 4) subsidizing firms with a prospector strategy and stimulate them to a higher ambition level can benefit both turnover and employee growth; and 5) specifically, mentoring and learning-by-doing types of support should be provided to fresh startups, while more “traditional” types of support can be given to older survivors. The use of the word art not only fits nicely into the title, but also associates some of the old wisdoms into the work. The choice of art here is the image that the word conjures up of being more fluid, and denotes a tendency of the world’s convergence that there may be some universal patterns underlying different phenomena. There may be no single approach or way to guarantee an appropriate level of openness within a firm or other organizations. Rather, the approach to being open must be crafted around the ecosystem created by the intersections and interactions between the firm’s internal resources, its virtually porous boundary, and the external resource/knowledge pool facilitated by networking relationships. Lessons and stories are presented in this thesis, however, how to make sense of them, and steer them for a better “performance” is truly and remains an art lies in the hands of various problem owners.

In order to develop a new philosophy of flood safety in terms of probability of a certain level, two mathematical models of breach growth in sandy dikes have become available to determine the flood discharge in case of dike failure. BREACHES 1.0, developed at Alkyon/Delft Hydraulics (Steetzel) and BRES 1.0 at Delft University of Technology (Visser) are different in principle. The comparison of these two models with the previous dam breach models was carried out. The validation of the two models using Dutch field sandy-dyke experimental data was conducted, the non-homogeneous fuse plug dam tests in China were also used as validation data. A suggestion to improve the capability of BRES model has been done.

This thesis presents the development a generic morphological model for both structured and unstructured grid and the extension to a biogeomorphological model. For the morphological model, numerical algorithms are adjusted to adapt unstructured grid and are validated against analytical solutions and flume experiments. For the bio-geomorphological extension, relevant ecological processes are coupled with morphodynamic processes at various scales and are validated against the field data in Lake Veluwe. Capability of the model has been explored for applications of two salt marsh restoration cases in United States and the large scale morphodynamics of shoreface connected radial sand ridges located in South-east China Sea. Validations and applications show that this modelling platform is capable to be a multidiscipline research tool for morphologists and ecologists / biologists.

Portland cement paste is a multiphase compound mainly consisting of calcium-silicate-hydrate (CSH) gel, calcium hydroxide (CH) crystal, and unhydrated cement core. When cement paste is exposed to high temperature, the dehydration of cement paste leads to not only the decline in strength, but also the increased pore pressure in the paste. In this article, the dehydration kinetic was characterized in term of the combination of kinetics of CSH and CH. The dehydration kinetics data of cement paste at different heating rates was collected by thermogravimetry. The influence of temperature on the reaction rate is analyzed by Arrhenius equation. The Arrhenius parameters of CSH and CH, activation energy, and pre-exponential factor are determined by isoconversional method. The calculated kinetics parameters were validated by further experimental data finally

Salt marshes are distributed along more than 400 km of the Jiangsu coast in Eastern China, which are regarded as important habitats and serve as coastal protection as well. Previous research has proven that salt-marsh vegetation can reduce current velocity and dampen waves by its stems and leaves. Reversely, hydrodynamic forces also have a significant influence on the growth of salt-marsh vegetation. To study the interaction between hydrodynamics and salt-marsh development on the Jiangsu coast, a 2D schematized model has been built by using a new interactive structure between flow, wave and vegetation modules of the process-based model Delft3D. In the hydrodynamic simulations, the impact of vegetation on waves and currents is quantified. In the vegetation growth module, the development of salt marshes is influenced by inundation time and shear stress from hydrodynamic simulations. The feedback loop is completed by hydrodynamic modules receiving the newly updated data of salt-marsh field from the vegetation growth module. The results show that wave height and current velocity are significantly influenced by vegetation. Reversely, the dynamics of marsh vegetation greatly rely on hydrodynamic conditions. Consequently, this interaction between hydrodynamics and salt marsh induces temporal variations of each other. In the model, the salt marsh is especially sensitive to the waves. Though wave height is relatively small on the Jiangsu coast, in terms of bed shear stress, waves may be of great importance to the development of salt marsh.

Open innovation is well conceptualized and researched for large established firms, but not for small and young ones. What makes small high-technology firms more open in search behaviour and innovation and others more closed, has remained largely unknown. This particularly holds true for university spin-off firms. The paper fills this gap and deals with the extent to which openness is adopted among university spin-off firms. Openness in this paper is measured by two dimensions, capacity and diversity, and an explanation is sought for the variation in these dimensions. For this purpose we develop a set of models including enabling factors and strategic intentions factors, and we control for competition in the business environment and density in the urban environment. Using an exploratory approach in regression analysis, our models of openness diversity (sources of knowledge use) tend to be stronger than the models of openness capacity (size of external knowledge pool). Openness diversity varies with four enabling factors, i.e., science-driven innovation, size of firm, size of founding team and pre-start experience, and with prospector strategy. Location tends also to be important, with a higher level of openness diversity in rural/peripheral areas. Finally, we develop a framework linking openness dimensions and growth of spin-off firms.