3,618 research outputs found

    Soil radium, soil gas radon and indoor radon empirical relationships to assist in post-closure impact assessment related to near-surface radioactive waste disposal

    Get PDF
    Least squares (LS), Theil’s (TS) and weighted total least squares (WTLS) regression analysis methods are used to develop empirical relationships between radium in the ground, radon in soil and radon in dwellings to assist in the post-closure assessment of indoor radon related to near-surface radioactive waste disposal at the Low Level Waste Repository in England. The data sets used are (i) estimated 226Ra in the <2 mm fraction of topsoils (eRa226) derived from equivalent uranium (eU) from airborne gamma spectrometry data, (ii) eRa226 derived from measurements of uranium in soil geochemical samples, (iii) soil gas radon and (iv) indoor radon data. For models comparing indoor radon and (i) eRa226 derived from airborne eU data and (ii) soil gas radon data, some of the geological groupings have significant slopes. For these groupings there is reasonable agreement in slope and intercept between the three regression analysis methods (LS, TS and WTLS). Relationships between radon in dwellings and radium in the ground or radon in soil differ depending on the characteristics of the underlying geological units, with more permeable units having steeper slopes and higher indoor radon concentrations for a given radium or soil gas radon concentration in the ground. The regression models comparing indoor radon with soil gas radon have intercepts close to 5 Bq m−3 whilst the intercepts for those comparing indoor radon with eRa226 from airborne eU vary from about 20 Bq m−3 for a moderately permeable geological unit to about 40 Bq m−3 for highly permeable limestone, implying unrealistically high contributions to indoor radon from sources other than the ground. An intercept value of 5 Bq m−3 is assumed as an appropriate mean value for the UK for sources of indoor radon other than radon from the ground, based on examination of UK data. Comparison with published data used to derive an average indoor radon: soil 226Ra ratio shows that whereas the published data are generally clustered with no obvious correlation, the data from this study have substantially different relationships depending largely on the permeability of the underlying geology. Models for the relatively impermeable geological units plot parallel to the average indoor radon: soil 226Ra model but with lower indoor radon: soil 226Ra ratios, whilst the models for the permeable geological units plot parallel to the average indoor radon: soil 226Ra model but with higher than average indoor radon: soil 226Ra ratios

    Security risk assessment and protection in the chemical and process industry

    Get PDF
    This article describes a security risk assessment and protection methodology that was developed for use in the chemical- and process industry in Belgium. The approach of the method follows a risk-based approach that follows desing principles for chemical safety. That approach is beneficial for workers in the chemical industry because they recognize the steps in this model from familiar safety models .The model combines the rings-of-protection approach with generic security practices including: management and procedures, security technology (e.g. CCTV, fences, and access control), and human interactions (pro-active as well as re-active). The method is illustrated in a case-study where a practical protection plan was developed for an existing chemical company. This chapter demonstrates that the method is useful for similar chemical- and process industrial activities far beyond the Belgian borders, as well as for cross-industrial security protection. This chapter offers an insight into how the chemical sector protects itself on the one hand, and an insight into how security risk management can be practiced on the other hand

    Ensembles of climate change models for risk assessment of nuclear power plants

    Get PDF
    Climate change affects technical Systems, Structures and Infrastructures (SSIs), changing the environmental context for which SSI were originally designed. In order to prevent any risk growth beyond acceptable levels, the climate change effects must be accounted for into risk assessment models. Climate models can provide future climate data, such as air temperature and pressure. However, the reliability of climate models is a major concern due to the uncertainty in the temperature and pressure future projections. In this work, we consider five climate change models (individually unable to accurately provide historical recorded temperatures and, thus, also future projections), and ensemble their projections for integration in a probabilistic safety assessment, conditional on climate projections. As case study, we consider the Passive Containment Cooling System (PCCS) of two AP1000 Nuclear Power Plants (NPPs). Results provided by the different ensembles are compared. Finally, a risk-based classification approach is performed to identify critical future temperatures, which may lead to PCCS risks beyond acceptable levels

    The effect of flight line spacing on radioactivity inventory and spatial feature characteristics of airborne gamma-ray spectrometry data

    Get PDF
    Airborne Gamma Spectrometry (AGS) is well suited to the mapping of radioactivity in the environment. Flight parameters (e.g. speed and line spacing) directly affect the rate of area coverage, cost, and data quality of any survey. The influences of line spacing have been investigated for data from inter‐tidal, coastal and upland environments with a range of &lt;sup&gt;137&lt;/sup&gt;Cs activity concentrations and depositional histories. Estimates of the integrated &lt;sup&gt;137&lt;/sup&gt;Cs activity (‘inventory’) within specified areas and the shapes of depositional features were calculated for subsets of the data at different line spacings. Features with dimensions greater than the line spacing show variations in inventory and area of less than 3%, and features with dimensions less than the line spacing show larger variations and a decreased probability of detection. The choice of line spacing for a task is dependent on the dimensions of the features of interest and required edge definition. Options for line spacing for different tasks are suggested. It is noted that for regional mapping, even 5–10 km line spacing can produce useful data

    Towards Resilience to Nuclear Accidents:Financing Nuclear Liabilities via Catastrophe Risk Bonds

    Get PDF
    In light of the 2011 Fukushima disaster, recent discussion has focused on finding the best nuclear storage options, maximizing the oversight power of global institutions, and strengthening safety measures. In addition to these, the development of dependable liability coverage that can be tapped in an emergency is also needed and should be considered thoughtfully. To succeed, financing is essential using special-purpose instruments from the global bond market, which is as big as US$175 trillion. Thus, in this paper, for the first time, a two-coverage-type trigger nuclear catastrophe (N-CAT) risk bond for potentially supplementing the covering of U.S. commercial nuclear power plants (NPPs) beyond the coverage per the Price Anderson Act as amended, and potentially other plants are proposed and designed worldwide. The N-CAT peril is categorized by three risk layers: incident, accident, and major accident. The pricing formula is derived by using a semi-Markovian dependence structure in continuous time. A numerical application illustrates the main findings of the paper.</jats:p

    Postoperative Management And Core Stabilization Interventions For A Semi-Pro Football Athlete Following Lumbar Discectomy: A Case Report

    Get PDF
    Background: Many cases of low back pain (LBP) are idiopathic in nature, however, LBP in result of a herniated intervertebral disc exerting pressure on the nerve root may require lumbar discectomy to relieve sciatica and radiating pain. Although there is evidence to support successful return to work in the general population and return to sports in professional athletes, less is known regarding the interventions that played a role in their return. Purpose: The purpose of this case report is to describe the physical therapy management and core stabilization interventions for a semi-pro football athlete following lumbar discectomy who sustained a herniated disc during recreational exercise and football.https://dune.une.edu/pt_studcrposter/1034/thumbnail.jp

    Who Gets What from International Organizations? The Case of the International Atomic Energy Agency’s Technical Cooperation

    Get PDF
    What affects the allocation of aid by international organizations to their member states? Using data on nuclear assistance by the International Atomic Energy Agency (IAEA), I demonstrate that political considerations affect the likelihood of receiving aid, and the amount of aid countries receive. Specifically, I find that membership in the IAEA Board of Governors or acceptance of tougher IAEA inspections increase the likelihood of IAEA assistance, and in some cases the amounts of assistance, but only for countries that do not share policy preferences with the US. This finding is consistent with theories that foreign aid is given in exchange for cooperation and concessions to recipients that are not likely to be cooperative without aid. I also examine whether nuclear assistance is given to countries that need it the most and that can make effective use of this aid, and find only partial support for need-based explanations of aid allocation

    Determination of the uptake and translocation of nitrogen applied at different growth stages of a melon crop (Cucumis melo L.) using 15N isotope.

    Full text link
    In order to establish a rational nitrogen (N) fertilisation and reduce groundwater contamination, a clearer understanding of the N distribution through the growing season and its dynamics inside the plant is crucial. In two successive years, a melon crop (Cucumis melo L. cv. Sancho) was grown under field conditions to determine the uptake of N fertiliser, applied by means of fertigation at different stages of plant growth, and to follow the translocation of N in the plant using 15N-labelled N. In 2006, two experiments were carried out. In the first experiment, labelled 15N fertiliser was supplied at the female-bloom stage and in the second, at the end of fruit ripening. Labelled 15N fertiliser was made from 15NH415NO3 (10 at.% 15N) and 9.6 kg N ha−1 were applied in each experiment over 6 days (1.6 kg N ha−1 d−1). In 2007, the 15N treatment consisted of applying 20.4 kg N ha−1 as 15NH415NO3 (10 at.% 15N) in the middle of fruit growth, over 6 days (3.4 kg N ha−1 d−1). In addition, 93 and 95 kg N ha−1 were supplied daily by fertigation as ammonium nitrate in 2006 and 2007, respectively. The results obtained in 2006 suggest that the uptake of N derived from labelled fertiliser by the above-ground parts of the plants was not affected by the time of fertiliser application. At the female-flowering and fruit-ripening stages, the N content derived from 15N-labelled fertiliser was close to 0.435 g m−2 (about 45% of the N applied), while in the middle of fruit growth it was 1.45 g m−2 (71% of the N applied). The N application time affected the amount of N derived from labelled fertiliser that was translocated to the fruits. When the N was supplied later, the N translocation was lower, ranging between 54% at female flowering and 32% at the end of fruit ripening. Approximately 85% of the N translocated came from the leaf when the N was applied at female flowering or in the middle of fruit growth. This value decreased to 72% when the 15N application was at the end of fruit ripening. The ammonium nitrate became available to the plant between 2 and 2.5 weeks after its application. Although the leaf N uptake varied during the crop cycle, the N absorption rate in the whole plant was linear, suggesting that the melon crop could be fertilised with constant daily N amounts until 2–3 weeks before the last harvest

    Consideration of urban green space in impact assessments for health

    Get PDF
    This paper explores how health aspects connected with the planning of urban green space are currently supported through two types of impact assessments: health impact assessment (HIA) and environmental assessment, including strategic environmental assessment (SEA) of policies, plans and programmes and environmental impact assessment (EIA) of projects. Seven HIAs and five EIAs/SEAs from the UK, the US, the Netherlands, Austria and Germany are reviewed, using an analytical framework designed on the basis of a literature review. An important finding is that whilst all HIAs follow a problem-/objectives-driven approach, designing guidelines for potential future projects, all EIAs/SEAs use an impact-driven approach, focusing on the impacts of planned and concrete action. HIAs therefore approach policy, plan, programme and project-making exercises from the outside, making suggestions to those working on them to consider certain aspects in the future, rather than working with them on improving things within a decision making process, as is usually is usually the case with EIAs/SEAs

    Comparing nuclear power trajectories in Germany and the UK: from ‘regimes' to ‘democracies’ in sociotechnical transitions and Discontinuities

    Get PDF
    This paper focuses on arguably the single most striking contrast in contemporary major energy politics in Europe (and even the developed world as a whole): the starkly differing civil nuclear policies of Germany and the UK. Germany is seeking entirely to phase out nuclear power by 2022. Yet the UK advocates a ‘nuclear renaissance’, promoting the most ambitious new nuclear construction programme in Western Europe.Here,this paper poses a simple yet quite fundamental question: what are the particular divergent conditions most strongly implicated in the contrasting developments in these two countries. With nuclear playing such an iconic role in historical discussions over technological continuity and transformation, answering this may assist in wider understandings of sociotechnical incumbency and discontinuity in the burgeoning field of‘sustainability transitions’. To this end, an ‘abductive’ approach is taken: deploying nine potentially relevant criteria for understanding the different directions pursued in Germany and the UK. Together constituted by 30 parameters spanning literatures related to socio-technical regimes in general as well as nuclear technology in particular, the criteria are divided into those that are ‘internal’ and ‘external’ to the ‘focal regime configuration’ of nuclear power and associated ‘challenger technologies’ like renewables. It is ‘internal’ criteria that are emphasised in conventional sociotechnical regime theory, with ‘external’ criteria relatively less well explored. Asking under each criterion whether attempted discontinuation of nuclear power would be more likely in Germany or the UK, a clear picture emerges. ‘Internal’ criteria suggest attempted nuclear discontinuation should be more likely in the UK than in Germany– the reverse of what is occurring. ‘External’ criteria are more aligned with observed dynamics –especially those relating to military nuclear commitments and broader ‘qualities of democracy’. Despite many differences of framing concerning exactly what constitutes ‘democracy’, a rich political science literature on this point is unanimous in characterising Germany more positively than the UK. Although based only on a single case,a potentially important question is nonetheless raised as to whether sociotechnical regime theory might usefully give greater attention to the general importance of various aspects of democracy in constituting conditions for significant technological discontinuities and transformations. If so, the policy implications are significant. A number of important areas are identified for future research, including the roles of diverse understandings and specific aspects of democracy and the particular relevance of military nuclear commitments– whose under-discussion in civil nuclear policy literatures raises its own questions of democratic accountability
    corecore