Methodological approach for measuring the effects of organisational-level interventions on employee withdrawal behaviour

Background: Theoretical frameworks have recommended organisational-level interventions to decrease employee withdrawal behaviours such as sickness absence and employee turnover. However, evaluation of such interventions has produced inconclusive results. The aim of this study was to investigate if mixed-effects models in combination with time series analysis, process evaluation, and reference group comparisons could be used for evaluating the effects of an organisational-level intervention on employee withdrawal behaviour. Methods: Monthly data on employee withdrawal behaviours (sickness absence, employee turnover, employment rate, and unpaid leave) were collected for 58 consecutive months (before and after the intervention) for intervention and reference groups. In total, eight intervention groups with a total of 1600 employees participated in the intervention. Process evaluation data were collected by process facilitators from the intervention team. Overall intervention effects were assessed using mixed-effects models with an AR (1) covariance structure for the repeated measurements and time as fixed effect. Intervention effects for each intervention group were assessed using time series analysis. Finally, results were compared descriptively with data from process evaluation and reference groups to disentangle the organisational-level intervention effects from other simultaneous effects. Results: All measures of employee withdrawal behaviour indicated statistically significant time trends and seasonal variability. Applying these methods to an organisational-level intervention resulted in an overall decrease in employee withdrawal behaviour. Meanwhile, the intervention effects varied greatly between intervention groups, highlighting the need to perform analyses at multiple levels to obtain a full understanding. Results also indicated that possible delayed intervention effects must be considered and that data from process evaluation and reference group comparisons were vital for disentangling the intervention effects from other simultaneous effects. Conclusions: When analysing the effects of an intervention, time trends, seasonal variability, and other changes in the work environment must be considered. The use of mixed-effects models in combination with time series analysis, process evaluation, and reference groups is a promising way to improve the evaluation of organisational-level interventions that can easily be adopted by others

A meta-evaluation of climate policy evaluations: findings from the freight transport sector

Knowledge about how implemented policy instruments have performed is important for designing effective and efficient policy instruments that contribute to reductions of greenhouse gas emissions. This paper carries out a meta-evaluation of ex-post evaluations of climate policy instruments in the freight transport sector. By analysing the outcomes and quality of evaluations, the aim is to identify whether estimated effects of policy instruments can be compared between evaluations and if the results are appropriate to use for evidence-based decision making. To analyse these aspects, commonly applied evaluation criteria are assessed and classified according to an assessment scale. We confirm that few ex-post evaluations are carried out and that there is a gap between evaluation theory and how ex-post policy evaluations are performed in practice, where evaluation criteria recommended in policy evaluation guidelines are found to often be neglected in evaluations. The result is a lack of systematic climate policy evaluation which hinders reliable conclusions about the effect of policy instruments. There is a need for more systematic monitoring and evaluation of implemented policy instruments and we suggest that evidence-based decision making can be improved by adjusting current policy evaluation guidelines and by introducing an evaluation obligation

Under pressure – The working situation of Swedish healthcare managers during the first wave of COVID-19

Introduction: The aim of this study is to provide insight into the psychosocial work situation of hospital managers during the first wave of the COVID-19 pandemic. Methods: Mixed-effect modelling was used on survey data on job demands, job resources, job motivation, and work-life balance among over 500 managers working in 55 departments of a large Swedish university hospital in 2019 and 2020. Responses from 6011 employees were then used to stratify the analysis for COVID-19 exposure. Inductive content analysis was applied to open-ended questions on the managers’ views on organisational prerequisites during the onset of the pandemic. Results: The proportion of managers reporting difficulties with role clarity, quantitative demands, decision-making authority, and emotional support, time for recovery at work, motivation deficits, or problems with work-life balance clearly increased during the first wave of the pandemic. The proportion of managers reporting negative responses was higher in departments with high COVID-19 exposure. The qualitative analysis shows that overall governance in terms of clear, fair, and well-communicated routines, resource allocation, and division of responsibilities constituted an important framework for managerial during the crisis. First-line managers also require a mandate to re-organize their roles and their teams to successfully adapt to the situation. Organisational and social support was also important resources. Discussion: This is the first study investigating healthcare managers’ work situation during the first wave of the COVID-19 pandemic in a Swedish context. As expected, it indicates an increasingly strained work situation during the crisis, but it also provides findings on organisational prerequisites that allow healthcare managers to cope with stressful situations. In line with previous research on organisational resilience, the study provides suggestions for how higher-level managers can act in order to provide front-line managers with the organisational prerequisites they need to adapt, learn and develop successfully during times of unpredictability, insecurity, and rapid change in order to offer the best possible support to health care workers

Making an ultralow platinum content bimetallic catalyst on carbon fibres for electro-oxidation of ammonia in wastewater

Electrocatalysis of wastewater containing ammonia is a promising alternative to chemical and biological water purification for several reasons, one being that energy-rich hydrogen gas is generated as a by-product while the reaction can be strictly controlled to meet demands. An objective has been to reduce the loading of expensive platinum (Pt) in the catalyst electrodes, and to reduce the poisoning of the metal surface during the electrolysis. Herein, the co-deposition of a copper-platinum (Cu-Pt) bimetallic alloy onto carbon filaments, stripped from their polymeric coating, is shown to give an electrocatalytic performance superior to that of pure Pt at a content of less than 3 wt% Pt. The key to the enhanced performance was to take advantage of micrometer-sized carbon filaments to distribute a very large bimetallic alloy surface uniformly over the filaments. The Cu-Pt-alloy-coated filaments also suffer less electrode poisoning than pure Pt, and are bonded more strongly to the carbon fibre due to better mechanical interlocking between the bimetallic alloy and the carbon filaments. High-resolution electron microscopy studies combined with a tuned electro-deposition process made it possible to tailor the catalyst micro/nano morphology to reach a uniform coverage, surrounding the entire carbon filaments. The results are promising steps towards large-scale wastewater treatment, combined with clean energy production from regenerated hydrogen

Thorium fuels for light water reactors - steps towards commercialization

Thorium-containing nuclear fuel is proposed as a means of gaining a number of benefits in the operation of light water reactors, some related to the nuclear properties of thorium and some related to the material properties of thorium dioxide. This thesis aims to investigate some of these benefits and to widen the knowledge base on thorium fuel behaviour, in order to pave the way for its commercial use.Part of the work is dedicated to finding ways of utilizing thorium in currently operating light water reactors which are beneficial to the reactor operator from a neutronic point of view. The effects of adding different fissile components to the fertile thorium matrix are compared, and the neutronic properties of the preferred alternative (plutonium) are more closely investigated. The possibility to use thorium as a minor component in conventional uranium dioxide fuel is also subject to study.Another part of the work is related to the thermal mechanical behaviour of thorium containing nuclear fuel under irradiation. To assess this behaviour, an irradiation experiment has been designed and is ongoing in the Halden research reactor. Existing software for prediction of thermal-mechanical fuel behaviour has been modified for application to mixed thorium and plutonium oxide fuel, and the preliminary simulation output is compared with irradiation data.The conclusion of the research conducted for this thesis is that the adoption of thorium containing fuel in light water reactors is indeed technically feasible and could also beattractive to reactor operators in a number of different aspects. Some steps have been taken towards a more complete knowledge of the behaviour of such fuel and therewith towards its commercial use

A BWR fuel assembly design for efficient use of plutonium in thorium–plutonium fuel

The objective of this study is to develop an optimized BWR fuel assembly design for thorium–plutonium fuel. In this work, the optimization goal is to maximize the amount of energy that can be extracted from a certain amount of plutonium, while maintaining acceptable values of the neutronic safety parameters such as reactivity coefficients, shutdown margins and power distribution. The factors having the most significant influence on the neutronic properties are the hydrogen-to-heavy-metal ratio, the distribution of the moderator within the fuel assembly, the initial plutonium fraction in the fuel and the radial distribution of the plutonium in the fuel assembly. The study begins with an investigation of how these factors affect the plutonium requirements and the safety parameters. The gathered knowledge is then used to develop and evaluate a fuel assembly design. The main characteristics of this fuel design are improved Pu efficiency, very high fractional Pu burning and neutronic safety parameters compliant with current demands on UOX fuel

Thorium-plutonium fuel for long operating cycles in PWRs - preliminary calculations

Preliminary calculations have been carried out to investigate the possibility of extending oper-ating cycle length in PWRs by use of Thorium-Plutonium mixed oxide fuel (Th-MOX). Thecalculations have been carried out in two dimensions, using the fuel assembly burnup simula-tion program CASMO-5. The reload scheme and the operating parameters are modelled on theSwedish PWR Ringhals 3 and a normal UOX fuel assembly designed for this reactor has beenused as a reference. Results show that an extension of the currently employed 12-month oper-ating cycle length is possible, either with a burnable absorber or with a modified fuel assemblydesign, assuming the same 3-batch reload scheme as currently used in Ringhals 3.The initial k∞ of the new Th-MOX fuel design was designed not to exceed that of the refer-ence UOX fuel. The power peaking factor is initially significantly lower than the reference,but slightly higher later in the life of the fuel assembly. All reactivity coefficients are withinacceptable range. The worth of control rods and soluble boron are lower than the reference, asexpected for a plutonium-bearing fuel

Thorium fuels for light water reactors - steps towards commercialization

Thorium-containing nuclear fuel is proposed as a means of gaining a number of benefits in the operation of light water reactors, some related to the nuclear properties of thorium and some related to the material properties of thorium dioxide. This thesis aims to investigate some of these benefits and to widen the knowledge base on thorium fuel behaviour, in order to pave the way for its commercial use.Part of the work is dedicated to finding ways of utilizing thorium in currently operating light water reactors which are beneficial to the reactor operator from a neutronic point of view. The effects of adding different fissile components to the fertile thorium matrix are compared, and the neutronic properties of the preferred alternative (plutonium) are more closely investigated. The possibility to use thorium as a minor component in conventional uranium dioxide fuel is also subject to study.Another part of the work is related to the thermal mechanical behaviour of thorium containing nuclear fuel under irradiation. To assess this behaviour, an irradiation experiment has been designed and is ongoing in the Halden research reactor. Existing software for prediction of thermal-mechanical fuel behaviour has been modified for application to mixed thorium and plutonium oxide fuel, and the preliminary simulation output is compared with irradiation data.The conclusion of the research conducted for this thesis is that the adoption of thorium containing fuel in light water reactors is indeed technically feasible and could also beattractive to reactor operators in a number of different aspects. Some steps have been taken towards a more complete knowledge of the behaviour of such fuel and therewith towards its commercial use

DEVELOPMENT OF A FUEL PERFORMANCE CODE FOR THORIUM-PLUTONIUM FUEL

Thorium-plutonium Mixed OXide fuel (Th-MOX) is considered for use as light water reactor fuel. Both neutronic and material properties show some clear benefits over those of uranium oxide and uranium-plutonium mixed oxide fuel, but for a new fuel type to be licensed for use in commercial reactors, its behaviour must be possible to predict. For the thermomechanical behaviour, this is normally done using a well validated fuel performance code, but given thescarce operation experience with Th-MOX fuel, no such code is available today.In this paper we present the ongoing work with developing a fuel performance code for prediction of the thermomechanical behaviour of Th-MOX for light water reactors. The wellestablished fuel performance code FRAPCON is modified by incorporation of new correlations for the material properties of the thorium-plutonium mixed oxide, and by develoment of a new subroutine for prediction of the radial power profiles within the fuel pellets. This paper lists the correlations chosen for the fuel material properties, describes the methodology for modifying the power profile calculations and shows the results of fuel temperature calculations with the code in its current state of development. The code will ultimately be validated using data from a Th-MOX test irradiation campaign which is currently ongoing in the Halden research reactor

Thorium as an additive for improved neutronic properties in boiling water reactor fuel

This article treats the replacement of burnable absorbers with a fertile absorber in boiling water reactor fuel. The target is to improve the fuel economy while meeting the same safety demands as the currently used conventional uranium oxide (UOX) fuel. A candidate fertile absorber is Th-232, and this work investigates the impact of replacing part of the U-238 in UOX fuel with Th-232. Computer simulations have been carried out and comparisons made for fuel assemblies with fertile and burnable absorbers, loaded in the boiling water reactor Oskarshamn 3, using the tools and methods that are normally employed for reload design and safety evaluation for this reactor. The results show that power balance and shutdown margins can be improved at the cost of higher enrichment needs. Alternatively, the fuel can be designed to just fulfil the relevant safety criteria, giving slightly lower uranium needs, which may compensate for the increased enrichment costs