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Als we zeggen dat we over een uurtje gaan eten, begrijpt iemand met een verstandelijke beperking dan wel wat bedoelen? Zo niet, dan heeft dat grote gevolgen voor zijn of haar gevoel van autonomie. Xavier Moonen doet onderzoek naar een hulpmiddel om de tijdsbeleving te verbeteren.
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The scope of this thesis of Gerrit Bouwhuis, lecturer at Saxion Research Centre for Design and Technology in Enschede is the development of a new industrial applicable pre-treatment process for cotton based on catalysis. The pre-treatment generally consists of desizing, scouring and bleaching. These processes can be continuous or batch wise. Advances in the science of biocatalytic pre-treatment of cotton and catalytic bleaching formed the scientific basis for this work. The work of Agrawal on enzymes for bio-scouring and of Topalovic on catalytic bleaching led to the conclusion that reduced reaction temperatures for the pre-treatment processes of cotton are possible. A second reason for the present work is a persistent and strong pressure on the industry to implement ‘more sustainable’ and environmental friendlier processes. It was clear that for the industrial implementation of the newly developed process it would be necessary to ‘translate’ the academic knowledge based on the catalysts, into a process at conditions that are applicable in textile industry. Previous experiences learned that the transition from academic knowledge into industrial applicable processes often failed. This is caused by lack of experience of university researchers with industrial product and process development as well as a lack of awareness of industrial developers of academic research. This is especially evident for the so-called Small and Medium Enterprises (SME’s). To overcome this gap a first step was to organize collaboration between academic institutes and industries. The basis for the collaboration was the prospect of this work for benefits for all parties involved. A rational approach has been adopted by first gathering knowledge about the properties and morphology of cotton and the know how on the conventional pre-treatment process. To be able to understand the conventional processes it was necessary not only to explore the chemical and physical aspects but also to evaluate the process conditions and equipment that are used. This information has been the basis for the present lab research on combined bio-catalytic desizing and scouring as well as catalytic bleaching. For the measurement of the performance of the treatments and the process steps, the performance indicators have been evaluated and selected. Here the choice has been made to use industrially known and accepted performance indicators. For the new bio-catalytic pre-treatment an enzyme cocktail, consisting of amylase, cutinase and pectinase has been developed. The process conditions in the enzyme cocktail tests have been explored reflecting different pre-treatment equipment as they are used in practice and for their different operation conditions. The exploration showed that combined bio-catalytic desizing and scouring seemed attractive for industrial application, with major reduction of the reaction and the rinsing temperatures, leading to several advantages. The performance of this treatment, when compared with the existing industrial treatment showed that the quality of the treated fabric was comparable or better than the present industrial standard, while concentrations enzymes in the cocktail have not yet been fully optimized. To explore the application of a manganese catalyst in the bleaching step of the pre-treatment process the fabrics were treated with the enzyme cocktail prior to the bleaching. It has been decided not to use conventional pre-treatment processes because in that case the combined desizing and scouring step would not be integrated in the newly developed process. To explore catalytic bleaching it has been tried to mimic the existing industrial processes where possible. The use of the catalyst at 100°C, as occurs in a conventional steamer, leads to decomposition of the catalyst and thus no bleach activation occurs. This led to the conclusion that catalytic bleaching is not possible in present steamers nor at low temperatur
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The continuous increase of accident and incident reports has indicated the potential of drones to threaten public safety. The published regulatory framework for small drones is not visibly based on a comprehensive hazard analysis. Also, a variety in the constraints imposed by different regulatory frameworks across the globe might impede market growth and render small-drone operations even more complicated since light drones might be easily transferred and operated in various regions with diverse restrictions. In our study we applied the Systems-Theoretic Process Analysis (STPA) method to small-drone operations and we generated a first set of Safety Requirements (SR) for the authority, manufacturer, end-user and automation levels. Under the scope of this paper, we reviewed 56 drone regulations published by different authorities, and performed (1) a gap analysis against the 57 SRs derived by STPA for the authority level, and (2) Intra-Class Correlations in order to examine the extent of their harmonization. The results suggest that the regulations studied satisfy 5.3% to 66.7% of the SRs, and they are moderately similar. The harmonization is even lower when considering the range of values of various SRs addressed by the authorities. The findings from the drones’ case show that regulators might not similarly and completely address hazards introduced by new technology; such a condition might affect safety and impede the distribution and use of products in the international market. A timely and harmonized standardization based on a systematic hazard analysis seems crucial for tackling the challenges stemmed from technological advancements, especially the ones available to the public.