174 research outputs found
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
Emissions of transboundary air pollutants in the Netherlands 1990-2012 : Informative Inventory Report 2014
Emissies Nederland blijven in 2012 onder nationale plafonds De uitstoot van stikstofoxiden (NOx), ammoniak, zwaveldioxide en niet-methaan vluchtige organische stoffen (NMVOS) is in 2012 in Nederland licht gedaald. Daarmee bleef de uitstoot onder de maxima die de Europese Unie daaraan sinds 2010 stelt. Nederland voldoet daardoor, net als in 2011, aan de vier 'nationale emissieplafonds' (NEC) voor deze stoffen. Dit blijkt uit de Nederlandse emissiecijfers van grootschalige luchtverontreinigende stoffen. Het RIVM verzamelt en analyseert deze cijfers. Behalve bovengenoemde stoffen gaat het om de uitstoot van koolmonoxide, fijn stof (PM10), zware metalen en persistente organische stoffen (POP's). De uitstoot van al deze stoffen is tussen 1990 en 2012 gedaald. Dit komt vooral door schonere auto's en brandstoffen en door emissiebeperkende maatregelen van industriële sectoren. Meer kilometers door bromfietsen Door de jaren heen zijn de methoden om de emissies te berekenen verbeterd, wat nu resulteert in nauwkeurigere cijfers. De emissies van bromfietsen en motorfietsen zijn afhankelijk van het aantal gereden kilometers per jaar en daar is nu beter inzicht in. Het totale aantal gereden kilometers door bromfietsen blijkt in de afgelopen jaren bijna twee keer zo hoog is als werd gedacht. Daarmee is de uitstoot van schadelijke stoffen navenant hoger. Ten opzichte van andere typ voertuigen blijven bromfietsen echter een relatief kleine emissiebron en dragen ze beperkt bij aan de totale nationale emissies. In steden zijn ze wel een relevante bron. Het aantal gereden kilometers door motorfietsen, en daarmee de uitstoot, blijft in lijn met eerdere inzichten. Vrachtauto's zwaarder beladen De uitstoot van schadelijke stoffen door vrachtauto's is voor het eerst berekend op basis van recente inzichten in het gewicht van vrachtauto's. Trekker-opleggers blijken zwaarder beladen dan tot nu toe werd verondersteld. Ook rijden vrachtauto's vaker met een aanhanger dan tot nu toe werd aangenomen, waardoor ze zwaarder zijn. Een hoger gewicht betekent een hoger brandstofverbruik, en veelal ook een hogere uitstoot per gereden kilometer. De uitstoot van PM10 door vrachtauto's is hierdoor circa 5 procent hoger dan in de vorige IIR-rapportage. Hogere emissies ammoniak De uitstoot van ammoniak blijkt hoger dan eerder werd verondersteld vanwege enkele nieuwe inzichten; de cijfers zijn hierdoor vanaf 1997 bijgesteld. Zo worden luchtwassers, die voornamelijk op varkensstallen zitten, niet altijd gebruikt. Ook is vanaf 2002 in melkveestallen het leefoppervlak per dier toegenomen. Door het grotere contactoppervlak van mest met lucht wordt meer ammoniak uitgestoten. Door de aangepaste aannames is het nationale totaal met 6,6 kiloton verhoogd ten opzichte van 2011.Emissions the Netherlands in 2012 remain under national ceilings Emissions of nitrogen oxides (NOx), ammonia, sulphur dioxide and non-methane volatile organic compounds (NMVOC) in the Netherlands have slightly decreased in 2012. Consequently, the emissions stayed below the caps the European Union has set from 2010. Herewith, the Netherlands comply with all four so-called emission ceilings (NEC). This has become apparent from the emission data on air pollutants from the Netherlands. RIVM collects and reports these data. Besides above-mentioned substances, emissions of carbon monoxide, particulate matter (PM10), heavy metals and persistent organic pollutants (POPs) have been reported. The emissions of all substances have decreased in the 1990 - 2012 period. The downward trend may in particular be attributed to cleaner fuels, cleaner car engines and to emission reductions in the industrial sectors. More kilometres by mopeds Over the years emission calculation methods have been improved, resulting in higher data accuracy. In 2012, the emissions from mopeds and motorcycles have been calculated, based on improved knowledge of the mileages. The total number of kilometres driven by mopeds appears to have been nearly twice as high in recent years. As a result, the emissions of pollutants are proportionally higher. In relation to the total number of vehicles, the number of mopeds however remains relatively low and their contribution to the total national emissions is limited. In cities, they are a relevant source. The mileages by motorcycles, and consequently their emissions remain in line with previous insights. Heavy-duty vehicles carry heavier loads Emissions of pollutants by heavy-duty trucks have for the first time been calculated on the basis of recent insights in truck loads. Tractor-trailer combinations appear to carry heavier loads and the fraction of trailers behind rigid trucks is larger than previously assumed. A heavier load means a higher fuel use and for most substances a higher emission per kilometre driven. PM10 emissions by heavy-duty trucks are about 5 percent higher than in the previous IIR report. Higher agricultural ammonia emissions Agricultural ammonia emissions appear to be higher than previously assumed because of new insights. Air scrubbers on animal housing (predominantly pigs) were not always in use or even employed. Since 2002, the living space per animal has increased for dairy cattle housing. This resulted in a higher contact surface manure-air and thus more ammonia emitted. The new insights have raised the national total of ammonia emissions by about 6 percent compared to 2011
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
Greenhouse gas emissions in The Netherlands 1990-2012 : National Inventory Report 2014
In 2012 is de totale uitstoot van broeikasgassen van Nederland, zoals CO2, methaan en lachgas, met ongeveer 1,7 procent gedaald ten opzichte van 2011. Deze daling komt vooral door een lager brandstofgebruik in de energie- en transportsector. Dit lijkt een gevolg van de economische recessie, waardoor emissies door elektriciteitsproductie en het wegtransport in Nederland zijn afgenomen. Cijfers De totale broeikasgasemissie wordt uitgedrukt in CO2-equivalenten en bedraagt in 2012 191,7 teragram (megaton of miljard kilogram) . Ten opzichte van de uitstoot in het Kyoto-basisjaar (213,2 Tg CO2-equivalenten) is dit een afname van ongeveer 10 procent. Het basisjaar, dat afhankelijk van het broeikasgas 1990 of 1995 is, dient voor het Kyoto-protocol als referentie voor de uitstoot van broeikasgassen. De uitstoot van de overige broeikasgassen zoals lachgas en methaan is sinds het basisjaar met 51 procent afgenomen. De CO2-uitstoot daarentegen is in deze periode met 4 procent gestegen. Landen zijn voor het Kyoto-protocol verplicht om de totale uitstoot van broeikasgassen op twee manieren te rapporteren: met en zonder het soort landgebruik en de verandering daarin. Dit is namelijk van invloed op de uitstoot van broeikasgassen. Voorbeelden zijn natuurontwikkeling (dat CO2 bindt) of ontbossing (waardoor CO2 wordt uitgestoten). In bovengenoemde getallen zijn deze zogeheten LULUCF-emissies (Land Use, Land Use Change and Forestry) niet meegenomen. Overige onderdelen inventarisatie Het RIVM stelt jaarlijks op verzoek van het Ministerie van Infrastructuur en Milieu (IenM) de inventarisatie van broeikasgasemissies op. De inventarisatie bevat trendanalyses om ontwikkelingen in de uitstoot van broeikasgassen tussen 1990 en 2012 te verklaren, en een analyse van de onzekerheid in deze getallen. Ook is aangegeven welke bronnen het meest aan deze onzekerheid bijdragen. Daarnaast biedt de inventarisatie documentatie van de gebruikte berekeningsmethoden, databronnen en toegepaste emissiefactoren. Met deze inventarisatie voldoet Nederland aan de nationale rapportageverplichtingen voor 2012 van het Klimaatverdrag van de Verenigde Naties (UNFCCC), van het Kyoto-Protocol en van het Bewakingsmechanisme Broeikasgassen van de Europese Unie.Total greenhouse gas emissions from the Netherlands in 2012 decreased by approximately 1.7 per cent, compared with 2011 emissions. This decrease is mainly the result of decreased fuel combustion in the Energy sector (increased electricity import) and in road transport. In 2012, total direct greenhouse gas emissions (excluding emissions from LULUCF - land use, land use change and forestry) in the Netherlands amounted to 191.7 Tg CO2 eq. This is approximately 10 per cent below the emissions in the base year (213.2 Tg CO2 eq.). The 51% reduction in the non-CO2 emissions in this period is counterbalanced by 4 per cent increase in CO2 emissions since 1990. This report documents the Netherlands' 2014 annual submission of its greenhouse gas emissions inventory in accordance with the guidelines provided by the United Nations Framework Convention on Climate Change (UNFCCC), the Kyoto Protocol and the European Union's Greenhouse Gas Monitoring Mechanism. The report comprises explanations of observed trends in emissions; a description of an assessment of key sources and their uncertainty; documentation of methods, data sources and emission factors applied; and a description of the quality assurance system and the verification activities performed on the data.Ministerie van I&
De kwestie voedingsgenomics: over afvallige burgers en eensgezinde experts
In deze essaybundel wordt gezocht naar toepassingen van genomics technologie en maatschappelijke contexten waarin dat gebeurt. Met die kennis is het mogelijk om te bekijken welke maatschappelijke impact voedingsgenomics heeft op de productie en consumptie van voeding. Daartoe hebben alfa- en gammawetenschappers vijf essays geschreven waarin maatschappelijke vraagstukken omtrent voedingsgenomics worden verkend: vanuit de optiek van de sociaal-economische organisatie van zowel de productie als de consumptie van voeding, over mondiale voedselzekerheid, wensen en zorgen van burgers en consumenten, en het gebruik van dieren
The issue of food genomics: about uncaring citizens and united experts
In this collection of essays is sought to find applications of genomics technology and the different social contexts in which this is and will be taking place. In this way it will be possible to reflect on the social impacts of food genomics on food production and food consumption. To this end social scientists have written five essays in which societal issues concerning food genomics are investigated and evaluated: from the viewpoint of the social-economic organisation of both production and consumption of food; on world food security; the wishes and concerns of citizens and consumers and the use of animal
- …