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[en] We present the results of a combined study from three UK universities where we investigate the existence and persistence of a performance gender gap in conceptual understanding of Newtonian mechanics. Using the Force Concept Inventory, we find that students at all three universities exhibit a statistically significant gender gap, with males outperforming females. This gap is narrowed but not eliminated after instruction, using a variety of instructional approaches. Furthermore, we find that before instruction the quartile with the lowest performance on the diagnostic instrument comprises a disproportionately high fraction (∼50%) of the total female cohort. The majority of these students remain in the lowest-performing quartile post-instruction. Analysis of responses to individual items shows that male students outperform female students on practically all items on the instrument. Comparing the performance of the same group of students on end-of-course examinations, we find no statistically significant gender gaps. (paper)
[en] The contribution deals with the methodology for analysis of the safety of ultimate storage facilities in deep geological formations after their closure (long-term safety). In particular the derivation of scenarios as an important basis of the safety analysis is examined. Due to different regulations, host rocks and ultimate storage concepts variations in the approach applied in different countries are unavoidable and incalculable. However, there are also numerous basic common features, which are outlined in the contribution. The question of the methodology of modern safety analysis is of special interest for Germany, because a ''Provisional safety analysis for Gorleben'' is currently being devised. (orig.)
[en] The amount of waste produced and the control of separate collection are crucial issues for the planning of a territorial Integrated Waste Management System, enabling the allocation of each sorted waste fraction to the proper treatment and recycling processes. The present study focuses on assessing indicators of different waste management systems in areas characterized by different territorial conditions. The investigated case study concerns the municipalities of Emilia Romagna (northern Italy), which present a rather uniform socioeconomic situation, but a variety of geographic, urban and waste management characteristics. A survey of waste generation and collection rates was carried out, and correlated with the different territorial conditions, classifying the municipalities according to altitude and population density. The best environmental performances, in terms of high separate collection rate, were found on average in rural areas in the plain, while the lowest waste generation was associated with rural hill towns.
[en] A brief introduction to UK's regulation of nuclear facility decommissioning in defense sector is presented. Apart from statutory regulation, internal regulation is exercised. The regulatory process and philosophy for both regulators are described, with a framework of joint work formed. The paper concludes with considering the movement towards a more coherent approach, because of less distinct differences in decommissioning of defense and civil nuclear facilities. (author)
[en] Optimization of LWR fuels is a continuous process particularly aimed at reducing the spent fuel arisings to be disposed of, for improving fuel cycle economics. The significant increase of fuel burn-up at end of life has had an impact on radwaste management strategies. Whereas the requirements to be met by recycling of the uranium and plutonium extracted from higher burn-up fuels are becoming increasingly severe, and the disposal of spent MOX fuels or fuels from reprocessing is penalized, other than disposal of spent fuels from fresh uranium, the interim dry storage of spent fuels in transport casks and storage drums poses difficulties resulting from the multitude of spent fuel parameters to be considered for an optimization of the ultimate disposal strategy. Siemens has developed consistent back-end fuel cycle processes both for the reprocessing option and the direct ultimate disposal option, together with the technique of early encapsulation. These techniques allow to reconcile the economic interests and advantages resulting from the fuel optimization and the requirements to be met by ultimate disposal of the spent fuels, thus safeguarding economic operation of nuclear power plants. (orig./DG)
[de]Betriebsoptimierung von LWR-Brennelementen ist ein kontinuierlicher Vorgang, der insbesondere der Reduktion der zu entsorgenden Brennstoffmasse und damit einer nachhaltigen Kostensenkung im Brennstoffkreislauf dient. Die im wesentlichen auf einer merklichen Erhoehung der Entladeabbraende beruhenden Fortschritte der letzten Jahre haben dazu gefuehrt, dass die Entsorgungspfade zunehmend beeinflusst werden. Waehrend beim Pfad der Wiederaufarbeitung die Anforderungen an die Rezyklierung der aus hoeher abgebrannten Brennelementen abgetrennten Spaltstoffe Uran und Plutonium steigen und die Entsorgung abgebrannter MOX- und WAU-Brennelemente gegenueber Brennelementen aus frischem Uran poenalisiert ist, sind es bei der trockenen Zwischenlagerung in Transport-und Lagerbehaeltern in erster Linie die vielen aus dem Betrieb der Brennelemente herruehrenden Parameter, die fuer eine optimierte Nutzung dieses Pfades genau betrachtet werden muessen. Siemens stellt sowohl fuer den Pfad der Wiederaufarbeitung als auch fuer den Pfad der Direkten Endlagerung ganzheitliche Verfahren und die Entwicklung der Fruehen Kapselung zur Verfuegung, um die sich aus der fortschreitenden Betriebsoptimierung der Brennelemente ergebenden oekonomischen Potentiale mit den Entsorgungsanforderungen in Einklang zu bringen und damit einen wirtschaftlichen Betrieb der Kernkraftwerke sicherzustellen. (orig.)
[en] SSI will amend and complete regulations and stipulations for nuclear plants in order to take into account issues which arise in connection with decommissioning. The objective of a pilot study, performed during 1998, was to identify the questions at issue, what the authority should control and how SSI should proceed with the work. The recommendations and the result of the pilot study are presented in this report
[en] Highlights: • Behaviours, opinions and knowledge of citizens on MSW management were investigated. • The knowledge level was better than that of nearby university students and citizens. • The higher the education level, the greater the level of knowledge was. • The local authority showed a leading role in terms of waste management. • Trust is the key to any social program success including waste management programs. - Abstract: Behaviours, opinions and knowledge of citizens on MSW and separate collection were investigated in the city of Mercato San Severino (about 22,000 people), in the Campania region of Southern Italy that is an area suffering from a serious solid waste emergency that has lasted over 17 years due to the absence of treatment facilities. The image of heaps of rubbish in the streets of Naples and other nearby cities is only one side of the coin. Mercato San Severino has adopted an effective kerbside collection system since 2001 and a pay-as-you-throw program during 2005, guaranteeing more than the minimum level of recycling required by the Italian legislation. Structured questionnaires were administered to a sample of 500 people in 2010. Chi-square tests of independence were applied to state whether the differences were statistically significant (5%). About 90% of the sample stated that the success of the separate collection program was due to either the citizens and local authority or only the local authority, highlighting the leading role of the local authority and confirming that trust is the key to any social program success. The registered level of knowledge was better than that of nearby university students and citizens. The higher the education level, the greater the level of knowledge was
[en] Highlights: ► The goal is to compare collection costs for residual household waste. ► We have clustered all municipalities in order to find mutual comparable pairs. ► Each pair consists of one private and one public operating waste collection program. ► All cases show that private service has lower costs than public service. ► Municipalities were contacted to identify the deeper causes for the waste management program. - Abstract: The rising pressure in terms of cost efficiency on public services pushes governments to transfer part of those services to the private sector. A trend towards more privatizing can be noticed in the collection of municipal household waste. This paper reports the findings of a research project aiming to compare the cost between the service of private and public collection of residual household waste. Multiple case studies of municipalities about the Flemish region of Belgium were conducted. Data concerning the year 2009 were gathered through in-depth interviews in 2010. In total 12 municipalities were investigated, divided into three mutual comparable pairs with a weekly and three mutual comparable pairs with a fortnightly residual waste collection. The results give a rough indication that in all cases the cost of private service is lower than public service in the collection of household waste. Albeit that there is an interest in establishing whether there are differences in the costs and service levels between public and private waste collection services, there are clear difficulties in establishing comparisons that can be made without having to rely on a large number of assumptions and corrections. However, given the cost difference, it remains the responsibility of the municipalities to decide upon the service they offer their citizens, regardless the cost efficiency: public or private.
[en] The aim of this analysis is to provide an estimated total Net Present Value of the future authorities' costs for the planned decommissioning programme, cf. the Swedish decommissioning legislation. The estimated total shall be usable as part of the calculations of the following year's unit fee and the related safety allowances for nuclear generated electricity to be paid by the owners of the Swedish nuclear power plants. These calculations are conducted by the Swedish Nuclear Power Inspectorate, SKI. The calculations in this analysis take account of the recommendations in respect of fees and safety allowances which will come into force in 2004. In addition, the uncertainty associated with the Net Present Value of the authorities' costs and the principal sources of uncertainty are assessed. In the course of two analysis sessions held between May and August 2003, a broad based analysis group examined the existing calculations and their references and preconditions. The group then identified and assessed the potential sources of uncertainty; and finally assessed the impact of these sources of uncertainty on the reference costs and incorporated the corresponding corrections in the analysis. The Successive Principle was used to optimise the quality of the result. Amongst other techniques, this involves using special processes for identifying and handling the sources of uncertainty. These processes allow neutral numerical evaluation results and correct statistical calculations to be obtained. The result includes the probable impact of external developments on the costs in future, albeit excluding any serious force majeure events. Future changes to the current fixed real interest rate are similarly excluded. Given clearly defined preconditions, with allowance being made inter alia for the current fixed real interest rate, the mean value result relating to the Net Present Value of the authorities' costs is 2,487 MSEK (about 350 MUSD) with an uncertainty of ± 674 MSEK, expressed as a standard deviation