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Using elemental analyses and multivariate statistics to identify the off-site dispersion from informal e-waste processing
Get PDFElectronic waste (e-waste) is informally processed and recycled in Agbogbloshie in Accra (Ghana), which may be the largest such site in West Africa. This industry can lead to significant environmental contamination. In this study, surface dust samples were collected at a range of sites within Accra to establish the offsite consequences of such activities. Fifty-one samples were collected and analysed for 69 elements by ICP-mass spectrometry after nitric acid digestion. The data indicated a significant enrichment in metals associated with solder and copper wire at the site itself and a downwind dispersion of this source material to a distance of approximately 2.0 km. Chlorine and bromine were also elevated at this site as residues from polyvinyl chloride combustion and flame retardants respectively. The elemental composition indicated that only low technology electrical equipment was being treated this way. Multivariate statistical analyses by principal components analysis and polytopic vector analysis identified three sources contributing to the system; (i) burn site residue dispersing within 2 km from the source site, (ii) marine matter on the beaches alone and (iii) the baseline soil conditions of the city of Accra. Risk ratios and hazard quotients developed from the measured concentrations indicated that copper was providing the greatest risk to inhabitants in most cases although nickel, vanadium, chromium and zinc also contributed.acceptedVersio
Risk of non-collision injuries to public transport passengers: Synthesis of evidence from eleven studies
Get PDFResearch problem This paper reviews and summarises studies of the risk of non-collision injuries to public transport passengers. Non-collision injuries include injuries when boarding or alighting and falls onboard as a result of e.g. sudden braking. It was possible to reconstruct exposure to risk for eleven studies, providing a total of twelve estimates of risk for boarding and alighting and twelve estimates of risk for falls onboard. Results The mean risk of falling in a moving vehicle is about 0.3–0.5 per million passenger kilometres. The mean risk of injury associated with boarding or alighting is about 0.8–1.7 per million passengers. Variability of results Estimates of risk are uncertain and vary substantially from study-to-study, largely for unknown reasons. Half of the estimates of exposure to risk were rated as very or somewhat uncertain.acceptedVersio
Macro-qualitative comparison - Grounded theory and the comparative case of Norwegian and Danish food industries since the 1990s transformations
Get PDFThis article examines macro-qualitative methodology specified for studies in comparative economic sociology. It elaborates a qualitative approach to comparative theory development. An examination of the socio-philosophical roots of social science theory is given, grounded theory methodology is reconstructed and research designs for macro-qualitative studies are discussed. It is argued that grounded theory methodology is able to contribute to macro-comparative studies as knowledge accumulation in case-specific research projects enables researchers to develop empirically grounded and plural notions of comparative theory. The research design presented for macro-qualitative inquiry builds on a middle-range attempt to accumulate knowledge in a micro-meso-macro procedure, including the productive examination of empirically grounded theoretical concepts at each analytical level. A previous macro-qualitative case study on Norwegian and Danish food industries since the 1990s turn is reconstructed to demonstrate how qualitative sociology is able to contribute to research frontiers that usually are dominated by quantitative economics.acceptedVersio
Citizenship in collision: Notions of agency in road safety work
Get PDFIn 2004, the Norwegian Accident Investigation Board (AIBN), previously restricted to civil aviation, was expanded to include a new section for road traffic, which was to investigate individual road accidents. The overall ambition behind the new organisation was to reduce the number of fatalities in road traffic. This article explores the idea that the main task of the Accident Investigation Board’s section for road traffic was to construct a new kind of narrative about road accidents, which would in turn open up new possibilities for intervention. The article examines what characterizes the narratives they have constructed and how these narratives interact with conceptions of risk and causality. It also discusses how they fit into the existing structure of road safety work in Norway. It concludes that the Accident Investigation Board’s narratives are implicitly political, as they partly deconstruct the notion of liberal citizenship underlying the legal system, and that this deconstruction can potentially have far-reaching practical consequences.publishedVersio
Comparison of regulated emission factors of Euro 6 LDV in Nordic temperatures and cold start conditions: Diesel- and gasoline direct-injection
Get PDFLocal air pollution in Norwegian wintertime is characterized by an increase in NO2 concentrations, due to poor dispersion and increased vehicle emissions. The focus of this study is therefore the characterisation of exhaust vehicle emissions in cold ambient temperatures. Euro 6 Gasoline Direct Injection (GDI) cars and diesel cars were tested in the laboratory in cold temperatures, including with cold start of the engine. Results show high emissions of CO2, PM and NOx. For the first time, we report also elevated NOx values for GDI vehicles. Further measurements are required to investigate whether these results are the beginning of a new trend of high NOx emissions from GDIs, or if these results represent singular events, but it may indicate that further NOx traps or catalysts are required for these vehicles. Understanding the relationship of cold ambient temperatures and vehicle emissions is also particularly important for air quality dispersion modelling, which do not currently account for emission temperature dependence.publishedVersio
A logistics cost function with explicit transport costs
Get PDFWith a view to construct a new framework to assess the benefits of freight transport improvements, an Economic Order Quantity model with uncertain lead time demand is equipped with detailed transport costs. The problem is to minimise total logistics cost by choosing shipment size, vehicle size and reorder point subject to constraints on vehicle size and annual transport capacity. An analytical solution in all variables except the reorder point is derived, reducing the cost minimisation problem to a well-behaved problem in one dimension only. Different parts of transport costs influence the solution differently: Some act like ordering costs, some like holding costs and some have no influence on the solution. The solution exhibits economies of scale at all levels of optimal shipment size. Examples with real data show that model calibration for an entire population of firms is feasible at the firm level, and that the model produces reasonable results.publishedVersio
A systematic cost-benefit analysis of 29 road safety measures
Get PDFEconomic evaluations of road safety measures are only rarely published in the scholarly literature. We collected and (re-)analyzed evidence in order to conduct cost-benefit analyses (CBAs) for 29 road safety measures. The information on crash costs was based on data from a survey in European countries. We applied a systematic procedure including corrections for inflation and Purchasing Power Parity in order to express all the monetary information in the same units (EUR, 2015). Cost-benefit analyses were done for measures with favorable estimated effects on road safety and for which relevant information on costs could be found. Results were assessed in terms of benefit-to-cost ratios and net present value. In order to account for some uncertainties, we carried out sensitivity analyses based on varying assumptions for costs of measures and measure effectiveness. Moreover we defined some combinations used as best case and worst case scenarios. In the best estimate scenario, 25 measures turn out to be cost-effective. 4 measures (road lighting, automatic barriers installation, area wide traffic calming and mandatory eyesight tests) are not cost-effective according to this scenario. In total, 14 measures remain cost-effective throughout all scenarios, whereas 10 other measures switch from cost-effective in the best case scenario to not cost-effective in the worst case scenario. For three measures insufficient information is available to calculate all scenarios. Two measures (automatic barriers installation and area wide traffic calming) even in the best case do not become cost-effective. Inherent uncertainties tend to be present in the underlying data on costs of measures, effects and target groups. Results of CBAs are not necessarily generally valid or directly transferable to other settings.acceptedVersio
How and why does intra-metropolitan workplace location affect car commuting?
Get PDFThis paper illuminates important causal processes that can explain differences between central, semi-central and suburban workplaces in commuting distances and modes. Its empirical base is qualitative interview material on the considerations and conditions underlying commuting behavior among employees of workplaces differently located within Oslo metropolitan area. The interviewees do not necessarily choose local jobs but rather travel a bit farther if this is necessary to find a more relevant job, especially if they have specialized job qualifications. Likewise, employers do not restrict their recruitment to local applicants. Workplaces close to the city center have a large number of potential employees within a short distance from the workplace and are therefore more likely to recruit workers locally. The interviewees’ rationales for travel mode choices, such as time-saving, flexibility, convenience and stress avoidance, encourage commuting by transit to central workplaces and by car to peripheral workplaces. For example, transit is often faster and more convenient than car when commuting to central workplaces, while the opposite is often the case for commutes to peripheral workplaces. Rationales of avoidance of stress and frustration and of predictability and control work in similar waysHow and why does intra-metropolitan workplace location affect car commuting?publishedVersio
Combining roadside interviews and on-road observation for assessing prevalence of driver inattention
Get PDFInattention among car drivers on a motorway section with two lanes in each direction was investigated by a combination of two different methodological approaches. First, an observer in a driving car in the non-passing (right) lane observed 1337 passing drivers; i.e., all drivers passing during the observation period. At a service area about midway along the section, 273 drivers were interviewed during the same period. The observations showed that 14% of drivers were involved in some secondary activity, with handheld mobile telephone use (which is prohibited) being the most frequent activity (5%). Involvement in secondary activities were far more frequent among drivers without passengers, with 15%, compared to 9% for drivers with passengers. For the latter, interaction with passengers was observed for 6%. The interviews made a useful supplement to roadside observations, providing prevalence estimates also for non-observable activities and states like daydreaming and listening to radio or music. Concerning passenger interaction, duration data were uncertain because many drivers tended to report total driving time with passengers rather than time interacting with them. Consequently, prevalence estimates for passenger interaction as reported in interviews were uncertain, and we therefore estimated this prevalence from observation data only. Total prevalence of secondary activities and internal states presumably implying inattention was estimated at about 24% of total driving time when based on both methods combined.acceptedVersio
Energy scenario analysis for the Nordic transport sector: A critical review
Get PDFExperiencing the highest growth in emissions since 1990 and relying mainly on oil, transport is considered the most complicated sector to decarbonize. Lately, the Nordic countries have shown remarkable success in reducing greenhouse gas (GHG) emissions, especially in the power and heat sector. However, when it comes to transportation, the greatest source of Nordic GHG emissions, stronger measures are needed. Relying on a rich and diversified portfolio of renewable sources and expertise, the Nordic countries could benefit from a common mitigation strategy by encompassing a larger variety of solutions and potential synergies. This article reviews studies addressing integrated energy and transport scenario analysis for the Nordic region as a whole. The studies targeted are those applying energy system models, given their extensive adoption in supporting scenario analysis. Most notable of these studies is the “Nordic Energy Technology Perspectives 2016” to which a special focus is dedicated. The article reviews the methodological choices and the research content of the selected literature. Challenges/limitations are identified in light of recent transport research, and categorized as: “transport behavior”, “breakthrough technologies”, “domestic energy resources” and “geographical aggregation and system boundaries”. Lastly, a list of suggestions to tackle the identified gaps is provided based on the existing literature.publishedVersio