Uncertainty Evaluation of Computational Model Used to Support the Integrated Powerhead Demonstration Project

NASA and the U.S. Air Force are working on a joint project to develop a new hydrogen-fueled, full-flow, staged combustion rocket engine. The initial testing and modeling work for the Integrated Powerhead Demonstrator (IPD) project is being performed by NASA Marshall and Stennis Space Centers. A key factor in the testing of this engine is the ability to predict and measure the transient fluid flow during engine start and shutdown phases of operation. A model built by NASA Marshall in the ROCket Engine Transient Simulation (ROCETS) program is used to predict transient engine fluid flows. The model is initially calibrated to data from previous tests on the Stennis E1 test stand. The model is then used to predict the next run. Data from this run can then be used to recalibrate the model providing a tool to guide the test program in incremental steps to reduce the risk to the prototype engine. In this paper, they define this type of model as a calibrated model. This paper proposes a method to estimate the uncertainty of a model calibrated to a set of experimental test data. The method is similar to that used in the calibration of experiment instrumentation. For the IPD example used in this paper, the model uncertainty is determined for both LOX and LH flow rates using previous data. The successful use of this model is then demonstrated to predict another similar test run within the uncertainty bounds. The paper summarizes the uncertainty methodology when a model is continually recalibrated with new test data. The methodology is general and can be applied to other calibrated models

Strafvorderlijke gegevensverwerking

As a result of society’s increasing digitisation, the police have ever more opportunities to collect, investigate and combine huge amounts of personal data using advanced technology. Examples are provided from recent cases where police have gained access to millions of encrypted messages from various servers, including Ennetcom, EncroChat and Sky Global. However, the current legal framework is, as yet, ill-equipped to deal with this new reality. Partly for this reason, legislators are facing new questions about how the (further) processing of data in detection should be regulated by law. Commissioned by the WODC, this study examines the legal safeguards in criminal justice data collection in relation to the legal safeguards governing the processing of these data. The Code of Criminal Procedure mainly focuses on the collection of data and to a much lesser extent on its further use, but this may involve a (fresh) invasion of citizens’ privacy. The Police Data Act contains some provisions to data processing, but the relationship with the Dutch Code of Criminal Procedure is not entirely clear. This study identifies the requirements and safeguards under European law for the processing of data for criminal justice purposes. Further inspiration is drawn from experience with the Intelligence and Security Services Act 2017 in which powers of collection and (further) processing are regulated in a single law. Finally, it explores how, in several countries (Germany, Belgium and Norway), the requirements arising from European law have been translated into legal regulations and how these regulations are designed. This study provides tools that legislators can use to reconsider the methods of standardisation and legal regulation design to better protect citizens' privacy. The recommendations thus focus on strengthening the legal framework on data processing and its supervision by creating an explicit legal framework in the Code of Criminal Procedure and establishing an independent supervisor focused on the processing of personal data by investigative authorities

Strafvorderlijke gegevensverwerking

As a result of society’s increasing digitisation, the police have ever more opportunities to collect, investigate and combine huge amounts of personal data using advanced technology. Examples are provided from recent cases where police have gained access to millions of encrypted messages from various servers, including Ennetcom, EncroChat and Sky Global. However, the current legal framework is, as yet, ill-equipped to deal with this new reality. Partly for this reason, legislators are facing new questions about how the (further) processing of data in detection should be regulated by law. Commissioned by the WODC, this study examines the legal safeguards in criminal justice data collection in relation to the legal safeguards governing the processing of these data. The Code of Criminal Procedure mainly focuses on the collection of data and to a much lesser extent on its further use, but this may involve a (fresh) invasion of citizens’ privacy. The Police Data Act contains some provisions to data processing, but the relationship with the Dutch Code of Criminal Procedure is not entirely clear. This study identifies the requirements and safeguards under European law for the processing of data for criminal justice purposes. Further inspiration is drawn from experience with the Intelligence and Security Services Act 2017 in which powers of collection and (further) processing are regulated in a single law. Finally, it explores how, in several countries (Germany, Belgium and Norway), the requirements arising from European law have been translated into legal regulations and how these regulations are designed. This study provides tools that legislators can use to reconsider the methods of standardisation and legal regulation design to better protect citizens' privacy. The recommendations thus focus on strengthening the legal framework on data processing and its supervision by creating an explicit legal framework in the Code of Criminal Procedure and establishing an independent supervisor focused on the processing of personal data by investigative authorities

Climate control of terrestrial carbon exchange across biomes and continents

Peer reviewe

High temperature gas effects for converging conical shocks

The flow associated with internal, conical shocks provides a useful basis for the design of supersonic and hypersonic air intakes. The analytical solutions to these flows, however, are limited to ideal gas models, but as the flow speeds increase into the hypervelocity regime, the high temperature gas effects may invalidate this ideal analysis. Chemical and thermal changes cause distortion to shock shape, which significantly alters the flow field and changes the behaviour of the shock reflections on the axis of symmetry. The computational work conducted here shows that high temperature effects can prevent the occurrence of Mach reflection for a given shock angle and hence drastically change the flow field. The computational results also show the formation of a strong curved shock structure at the centreline which requires further investigation. A preliminary experimental campaign was conducted in the X2 expansion tube at Mach 8.1 and Mach 10 flows. Experimental imagery of the shock structure formation at the centre line clearly exhibited the upstream travelling, bulbous Mach stem that had been predicted by CFD analysis

Kryogene Infrastruktur bei BESSY II Bestand und Ausblick

Das Helmholtz Zentrum Berlin betreibt am Standort Adlershof u.a. den Elektronenspeicherring BESSY II. Für die Versorgung der im Speicherring installierten supraleitenden Wellenlängenschieber mit Flüssighelium ist ein He liumverflüssiger installiert. Ein weiterer Verflüssiger, inklusive umfassender kryogener Infrastruktur, versorgt mehrere Teststände, vor allem für supraleitende Hohlraumresonatoren, mit Helium bei 1,8 K. Neben dem Betrieb der existierenden Anlagen wird derzeit ein neuartiger Beschleunigertyp im Rahmen des Pro jektes bERLinPro aufgebaut. Um die benötigte Versorgung mit Flüssighelium zu gewährleisten, wird einer der bestehenden Heliumverflüssiger umgezogen sowie die Anlage um u.a. einen 10.000 l Dewar, drei Ventilboxen, eine Kaltkompressorbox, einen warmen Pumpstand und ein 80 K Helium System erweitert. Au erdem ist für das Zukunftsprojekt BESSY VSR, einer Weiterentwicklung des Speicherrings BESSY II, die Be schaffung einer dritten Kälteanlage geplant. Eine Herausforderung hierbei wird der ganzjährig durchgängige Be trieb sein. In diesem Papier wird der Aufbau der oben beschriebenen Anlagen detaillierter erläutert und ein Einblick in die Herausforderungen bei der Anlagenplanung gegeben. Abschlie end werden die geplanten zukünftigen Erweite rungen skizzier

Quitting is not an option: An analysis of online diet talk between celiac disease patients

This is an empirical study of the way in which celiac disease patients manage the risk of gluten intake in their everyday life. The article examines naturally occurring conversational data in order to study how patients cope interactionally with constantly being at risk in their day-to-day living. They reject quitting the diet as a valid option, and instead construct a ‘diet world’ in which dietary transgression is presented as an integrated part of everyday life. In this way, patients can manage occasional diet lapses without putting the validity of the diet itself at stake. By examining how the gluten-free diet is treated in interaction, we find out more about the pre-existing everyday strategies that have to be taken into account when new therapies are being introduced