An impulse control approach to dike height optimization

This paper determines the optimal timing of dike heightenings as well as the corresponding optimal dike heightenings to protect against floods. To derive the optimal policy, we design an algorithm based on the Impulse Control Maximum Principle. In this way, this paper presents one of the first real-life applications of the Impulse Control Maximum Principle developed by Blaquière. We show that the proposed impulse control (IC) approach performs better than dynamic programming with respect to computational time. This is caused by the fact that IC does not need discretization in time.     

User experimentation: an evaluation of velocity control techniques in immersive virtual environments

While many of the existing velocity control techniques are well designed, the techniques are often application-specific, making it difficult to compare their effectiveness. In this paper, we evaluate five known velocity control techniques using the same experimental settings. We compare the techniques based on the assumption that a good travel technique should be easy to learn and easy to use, should cause the user to have few collisions with the VE, should allow the user to complete tasks faster, and should promote better recollection of the environment afterwards. In our experiments, we ask twenty users to use each velocity control technique to navigate through virtual corridors while performing information-gathering tasks. In all cases, the users use pointing to indicate the direction of travel. We then measure the users’ ability to recollect the information they see in the VE, as well as how much time they spend in the VE and how often they collide with the virtual walls. After each test, we use questionnaires to evaluate the ease of learning and ease of use of the velocity control technique, and the users’ sense of presence in the environment. Each of the travel techniques is then evaluated based on the users’ performances in the VE and the results of their questionnaires.     

A 3D face matching framework for facial curves

Among the many 3D face matching techniques that have been developed, are variants of 3D facial curve matching, which reduce the amount of face data to one or a few 3D curves. The face’s central profile, for instance, proved to work well. However, the selection of the optimal set of 3D curves and the best way to match them has not been researched systematically. We propose a 3D face matching framework that allows profile and contour based face matching. Using this framework we evaluate profile and contour types including those described in the literature, and select subsets of facial curves for effective and efficient face matching. With a set of eight geodesic contours we achieve a mean average precision (MAP) of 0.70 and 92.5% recognition rate (RR) on the 3D face retrieval track of the Shape Retrieval Contest (SHREC’08), and a MAP of 0.96 and 97.6% RR on the University of Notre Dame (UND) test set. Face matching with these curves is time-efficient and performs better than other sets of facial curves and depth map comparison.     

APROMORE: An advanced process model repository

Business process models are becoming available in large numbers due to their widespread use in many industrial applications such as enterprise and quality engineering projects. On the one hand, this raises a challenge as to their proper management: how can it be ensured that the proper process model is always available to the interested stakeholder? On the other hand, the richness of a large set of process models also offers opportunities, for example with respect to the re-use of existing model parts for new models. This paper describes the functionality and architecture of an advanced process model repository, named APROMORE. This tool brings together a rich set of features for the analysis, management and usage of large sets of process models, drawing from state-of-the art research in the field of process modeling. A prototype of the platform is presented in this paper, demonstrating its feasibility, as well as an outlook on the further development of APROMORE.     

Linear Image Reconstruction by Sobolev Norms on the Bounded Domain

The reconstruction problem is usually formulated as a variational problem in which one searches for that image that minimizes a so called prior (image model) while insisting on certain image features to be preserved. When the prior can be described by a norm induced by some inner product on a Hilbert space, the exact solution to the variational problem can be found by orthogonal projection. In previous work we considered the image as compactly supported in and we used Sobolev norms on the unbounded domain including a smoothing parameter γ>0 to tune the smoothness of the reconstructed image. Due to the assumption of compact support of the original image, components of the reconstructed image near the image boundary are too much penalized. Therefore, in this work we minimize Sobolev norms only on the actual image domain, yielding much better reconstructions (especially for γ≫0). As an example we apply our method to the reconstruction of singular points that are present in the scale space representation of an image.     

Theoretical and experimental research on the in-plane comb-shaped capacitor for MEMS coriolis mass flow sensor

The Micro-Electro-Mechanical System Coriolis mass flow sensor uses a kind of in-plane comb-shaped capacitor to detect the vibration of tube containing the micro flow information. This paper takes the deflection of the micro tube caused by Coriolis force into account and models the in-plane comb-shaped capacitor of the sensor based on the electrostatic field method. Then the modulation and demodulation of the output capacitive signals are described in detail. The theoretical waveforms obtained by substituting the actual parameters into the models are consistent with the accepted conformal mapping method and match with the sampling signals, which attest the two models. According to the actual flow calibration experiment and the preliminary phase shift calculation, the measurement accuracy of the micro flow sensor reaches ±1.5 % with the repeatability of 0.75 % within 0–1.2 g/h flow range.     

A versatile technology platform for microfluidic handling systems,part II: channel design and technology

Microfluidic devices often require channels of a specific size and shape. These devices are then made in a fabrication process that is often specialized to produce only those (and very similar) channels. As a result, devices requiring channels of different size and shape cannot easily be integrated on the same chip. This paper presents a method to fabricate microfluidic channels in a wide range of shape and size on the same chip by using a slit pattern through which the channels are etched. The fabrication process to fabricate these channels is discussed in detail, and an empirical model is presented to find the optimal slit pattern for a required size and shape. This part of the paper focusses on the channel design and fabrication. Details on the whole fabrication process and optional functionalization of the channels are presented in part I of this paper.     

A Reusable Multi-Agent Architecture for Active Intelligent Websites

In this paper a reusable multi-agent architecture for intelligent Websites is presented and illustrated for an electronic department store. The architecture has been designed and implemented using the compositional design method for multi-agent systems DESIRE. The agents within this architecture are based on a generic information broker agent model. It is shown how the architecture can be exploited to design an intelligent Website for insurance, developed in co-operation with the software company Ordina Utopics and an insurance company.     

The indoor environment and the integrated design of homes for older people with dementia

There are currently about 6 million – mainly older – people with dementia in the European Union. With ageing, a number of sensory changes occur. Dementia syndrome exacerbates the effects of these sensory changes and alters perception of stimuli. People with dementia have an altered sensitivity for indoor environmental conditions, which can induce problematic behaviour with burdensome symptoms to both the person with dementia and the family carer. This paper, based on literature review, provides an overview of the indoor environmental parameters, as well as the integrated design and implementation of relevant building systems. The overview is presented in relation to the intrinsic ageing of senses, the responses of older people with dementia and the impact on other relevant stakeholders through the combined use of the International Classification of Functioning, Disability and Health, and the Model of Integrated Building Design. Results are presented as indicators of the basic value, functional value and economic value, as well as a synthesis of building-related solutions. Results can help designers and building services engineers to create optimal environmental conditions inside the living environments for people with dementia, and can be used to raise awareness among health care professionals about of the influence of the indoor environment on behaviour of the person with dementia.