The effect of maintenance policy violations - Rijsdijk, C.; Tinga, T.
Maintenance policy assessments usually rely on expert judgement. We seek for some history based validation. Organisations may use our inference to assess risks of maintenance policy violations.
We depart from the arbitrary viewpoint that decisions have observable effects. We confine to a dependency between a maintenance policy and functionality. We implement (Granger, 1980)’s notion of prima facie causality that suits history based inferences under an observational study. A case study which is realistic in terms of sample size and operationalization allows us to reflect on inference precision.
We implemented an argument to infer a prima facie cause between a maintenance policy...
Innovative predictive maintenance concepts to improve life cycle management - Tinga, T.
For naval systems with typically long service lives, high sustainment costs and strict availability requirements, an effective and efficient life cycle management process is very important. In this paper four approaches are discussed to improve that process: physics of failure based predictive maintenance, advanced data analysis, condition based maintenance and maintenance optimization. For all these approaches, understanding of the failure behaviour and quantifying the effects of variations in usage of the system appear to be the key factor for improvements.
High-quality global hydrogen silsequioxane contact planarization for nanoimprint lithography - Büyükköse, S.; Vratzov, B.; Wiel, W.G. van der
The authors present a novel global contact planarization technique based on the spin-on-glass material hydrogen silsequioxane (HSQ) and demonstrate its excellent performance on patterns of 70 nm up to several microns generated by UV-based nanoimprint lithography. The HSQ layer (∼165 nm) is spin coated on the imprinted organic layer and planarized by pressing it with a flat wafer at room temperature. Before retracting the planarization wafer, the HSQ is hardened by baking at 120 or 70 °C , depending on the underlying material. Fluorine-based reactive ion etching (RIE) is used to etch the HSQ (etch-back) down to the top of the features...
Options for a National Framework for Benefit Distribution and Their Relation to Community-Based and National REDD+ Monitoring - Skutsch, Margaret; Turnhout, Esther; Vijge, Marjanneke J.; Herold, Martin; Wits, Tjeerd; Besten, Jan Willem den; Balderas Torres, Arturo
Monitoring is a central element in the implementation of national REDD+ and may be essential in providing the data needed to support benefit distribution. We discuss the options for benefit sharing systems in terms of technical feasibility and political acceptability in respect of equity considerations, and the kind of data that would be needed for the different options. We contrast output-based distribution systems, in which rewards are distributed according to performance measured in terms of carbon impacts, with input-based systems in which performance is measured in term of compliance with prescribed REDD+ activities. Output-based systems, which would require regular community...
Experimental studies to improve the reliability and validity of regulatory judgments on health care in the Netherlands: a randomized controlled trial and before and after case study - Tuijn, Saskia M.; Bergh, Huub van den; Robben, Paul; Janssens, Frans
Rationale, aims and objectives
We examined the effect of two interventions on both the reliability and validity of regulatory judgments: adjusting the regulatory instrument and attending a consensus meeting.
We adjusted the regulatory instrument. With a randomized controlled trial (RCT) we examined the effect of the adjustments we made to the instrument. In the consensus meeting inspectors discussed cases and had to reach consensus about the order of the cases. We used a before and after case study to assess the effect of the consensus meeting. We compared the judgments assigned in the RCT with the unadjusted instrument with the judgments assigned...
Assessing writing ability in primary education: on the evaluation of text quality and text complexity - Feenstra, Hiske Marianne
Writing is a complex ability, and measuring writing ability is a notoriously complex task. The assessment of writing ability is complicated by the multi-faceted nature of this productive language ability on one hand, and the difficulty of evaluating writing performances on the other hand. In this dissertation, different methods to assess both the quality and the complexity of novice writers’ texts are evaluated with the aim of improving the validity and reliability of writing assessment in primary education.
Each of the three methods discussed in this study assesses a different aspect of the construct of writing ability. An anchored analytical...
Optimization of radiation sensors for a passive terahertz video camera for security applications - Zieger, Gabriel
A passive terahertz video camera allows for fast security screenings from distances of several meters. It avoids irradiation or the impressions of nakedness, which oftentimes cause embarrassment and trepidation of the concerned persons. This work describes the optimization of highly sensitive superconducting transition edge sensor bolometers (TES) for such a system. They enable frame rates of up to 25 Hz and have the capability to also detect non-metallic objects.Several challenges were addressed in this work:Based on a series of oxidation experiments, the sensor design could be optimized to achieve significant enhancements in long term parameter stability and reproducibility. Further measurements...
Single domain antibodies in tissue engineering - Rodrigues, Emilie Dooms
The aim of this thesis is to demonstrate the potential of VHH in tissue engineering applications, with a focus on bone and cartilage tissue regeneration. After a general introduction to this thesis in chapter 1, the selection of VHH targeting growth factors is described in chapter 2. VHH were selected to target growth factors relevant in skeletal tissue engineering and VHH were found to modulate BMP activity with high affinity. Chapter 3 describes the immobilization of VHH and its potential to reversibly immobilize BMP6 to a surface. The strategy consisted in the combination of orthogonal supramolecular interactions for the immobilization...
Identifying key domains of health-related quality of life for patients with Chronic Obstructive Pulmonary Disease: the patient perspective - Paap, Muirne C.S.; Bode, Christina; Lenferink, Lonneke I.M.; Groen, Lianne C.; Terwee, Caroline B.; Ahmed, Sara; Eilayyan, Owis; Palen, Job van der
Numerous instruments are available to measure health-related quality of life (HRQoL) in patients with Chronic Obstructive Pulmonary Disease (COPD), covering a wide array of domains ranging from symptoms such as dyspnea, cough and wheezing, to social and emotional functioning. Currently no information or guide is available yet to aid the selection of domains for a particular study or disease population. The aim of this paper is to identify which domains of HRQoL are most important with respect to COPD, from the patient perspective.
Twenty-one Dutch patients with COPD were asked to describe important domains impacted by COPD freely; second, they...
An ECHO in biology: Validating the Executable CHondrocyte - Scholma, J.; Schivo, S.; Karperien, M.; Langerak, R.; Pol, J. van de; Post, J.N.
Computational modeling of biological networks permits comprehensive analysis of cells and tissues to define molecular phenotypes and novel hypotheses. We recently presented ANIMO (Analysis of Networks with Interactive Modeling), an intuitive software tool for modeling molecular networks for use by biologists. We used ANIMO to generate a computational model of articular cartilage, ECHO. Over 1.5 million people in the Netherlands suffer from osteoarthritis (OA) in one or more joints. OA is a painful, disabling disease and currently cannot be cured. In a subset of OA patients, joint cartilage is replaced by bone via endochondral ossification. This is a natural process...