MARANGONI CONVECTION AROUND A VENTILATED AIR BUBBLE UNDER MICROGRAVITY CONDITIONS

Under microgravity conditions in both parabolic and sounding rocket flights, the mass-transfer-induced Marangoni convection around an air bubble was studied. To prevent the bubble from becoming saturated, the bubble was ventilated. It turned out that the flow rate of the air through the bubble determined the flow pattern in the liquid. A mathematical model is presented which can adequately describe the observed phenomena.</p

Evaluation and prediction of high-rise building settlements based on satellite data

High-rise buildings in the western part of The Netherlands are subject to settlement as a result of compression of deep-lying cohesive layers. The size of the compression and creep deformation depends on the load increment in the compressible layers which is determined by building dimensions, permanent load and foundation level. In addition, the properties of the compressible layers are important. A great uncertainty herein is the pre-consolidation stress or initial creep rate of these layers. On the basis of InSAR - satellite data of existing high-rise buildings, the current settlement rate can be measured and a good estimate is possible of, in particular, the pre-consolidation stress in the compressible layers resulting in the observed settlement rate

The co-production of the Metropolitan Water Observatory (MWO) platform

This working paper examines the development and design of the Observatorio Metropolitano de Agua para Lima-Callao (MWO): a co-produced digital observatory for water and data justice.The metropolitan city of Lima and Callao (hereafter referred to as Lima) faces a water security challenge, which results from the combination of scarce water resources with inefficient and unequal distribution. The lack or limited water access has been a crucial factor shaping inequality patterns in the city. Amongst the challenges for improving water distribution are the difficulties around mapping water needs and the lack of adequate and comprehensive data for all citizens since a significant part of the population is excluded from formal government datasets. Those living in subservice areas, who do not have access to administrative or political structures, and migrants are examples of such exclusion from formal government sources for evidence-based policy and implementation. The purpose of the MWO is to contribute to a fairer distribution of water resources amongst urban residents within Lima. By combining collaborative design approaches with the theory-informed data justice guidelines, we have developed a prototype of the MWO with participants from three districts in Lima. The MWO aims to challenge the hegemonic representation of Lima’s water infrastructure and help communicate the experiences and views of residents currently overlooked. In addition, the MWO teaches us how to design digital platforms according to the principles of data justice in practice