Experimental study of electric breakdowns in liquid argon at centimeter scale

In this paper we present results on measurements of the dielectric strength of liquid argon near its boiling point and cathode-anode distances in the range of 0.1 mm to 40 mm with spherical cathode and plane anode. We show that at such distances the applied electric field at which breakdowns occur is as low as 40 kV/cm. Flash-overs across the ribbed dielectric of the high voltage feed-through are observed for a length of 300 mm starting from a voltage of 55 kV. These results contribute to set reference for the breakdown-free design of ionization detectors, such as Liquid Argon Time Projection Chambers (LAr TPC)

Target and (Astro-)WISE technologies - Data federations and its applications

After its first implementation in 2003 the Astro-WISE technology has been rolled out in several European countries and is used for the production of the KiDS survey data. In the multi-disciplinary Target initiative this technology, nicknamed WISE technology, has been further applied to a large number of projects. Here, we highlight the data handling of other astronomical applications, such as VLT-MUSE and LOFAR, together with some non-astronomical applications such as the medical projects Lifelines and GLIMPS, the MONK handwritten text recognition system, and business applications, by amongst others, the Target Holding. We describe some of the most important lessons learned and describe the application of the data-centric WISE type of approach to the Science Ground Segment of the Euclid satellite.Comment: 9 pages, 5 figures, Proceedngs IAU Symposium No 325 Astroinformatics 201

Change management - practising what we teach: successfully engaging international students in the teaching, learning & assessment process

In this article we review processes of change in a module whose subject matter is change management. The module attracts mainly international students, and has suffered from uneven student engagement and performance. We will recount how a Teaching Enhancement and Student Success (TESS) project was used to inform our attempts to improve engagement and performance. Bearing in mind the origins of action research as part of Kurt Lewin‟s approach to planned change, we will use the four different elements of Lewin‟s work to reflect on the challenges we have been grappling with. The article will highlight different approaches to action research, which are linked to different aspirations as to the scope of change

A review of NASA-sponsored technology assessment projects

Recent technology assessment studies sponsored by NASA are reviewed, and a summary of the technical results as well as a critique of the methodologies are presented. The reviews include Assessment of Lighter-Than-Air Technology, Technology Assessment of Portable Energy RDT&P, Technology Assessment of Future Intercity Passenger Transportation Systems, and Technology Assessment of Space Disposal of Radioactive Nuclear Waste. The use of workshops has been introduced as a unique element of some of these assessments. Also included in this report is a brief synopsis of a method of quantifying opinions obtained through such group interactions. Representative of the current technology assessments, these studies cover a broad range of socio-political factors and issues in greater depth than previously considered in NASA sponsored studies. In addition to the lessons learned through the conduct of these studies, a few suggestions for improving the effectiveness of future technology assessments are provided

Effect of zeolite types LTX and LTA on physicochemical parameters of drinking water sample in Ghana, assisted by light transmission experiment

In this study, the effect of zeolite types LTX and LTA, assisted by laser light transmission experiment on the physico-chemical parameters of drinking water samples have been investigated. Water samples were collected from rivers, streams, and wells from Central and Volta regions of Ghana, and zeolite masses of 0.2 and 0.5 g were added to 100 ml portions of the samples in turn. Laser light intensities transmitted through the samples before and after zeolite addition were measured and recorded. The results obtained showed raw water turbidity of 33.8 NTU and treated water turbidity of 3.0 NTU (WHO recommends the limit of 5 NTU for drinking water); transmitted light intensity for the raw and treated water samples of 0.3122 AU and 0.3345 AU, respectively. Our results also showed that water turbidity highly correlates the transmitted light intensity, and water conductivity depends on dissolved metal concentrations and temperature