Assessment of Integrated Pedestrian Protection Systems with Autonomous Emergency Braking (AEB) and Passive Safety Components

Objective: Autonomous emergency braking (AEB) systems fitted to cars for pedestrians have been predicted to offer substantial benefit. On this basis, consumer rating programs—for example, the European New Car Assessment Programme (Euro NCAP)—are developing rating schemes to encourage fitment of these systems. One of the questions that needs to be answered to do this fully is how the assessment of the speed reduction offered by the AEB is integrated with the current assessment of the passive safety for mitigation of pedestrian injury. Ideally, this should be done on a benefit-related basis.

The objective of this research was to develop a benefit-based methodology for assessment of integrated pedestrian protection systems with AEB and passive safety components. The method should include weighting procedures to ensure that it represents injury patterns from accident data and replicates an independently estimated benefit of AEB.

Methods: A methodology has been developed to calculate the expected societal cost of pedestrian injuries, assuming that all pedestrians in the target population (i.e., pedestrians impacted by the front of a passenger car) are impacted by the car being assessed, taking into account the impact speed reduction offered by the car's AEB (if fitted) and the passive safety protection offered by the car's frontal structure. For rating purposes, the cost for the assessed car is normalized by comparing it to the cost calculated for a reference car.

The speed reductions measured in AEB tests are used to determine the speed at which each pedestrian in the target population will be impacted. Injury probabilities for each impact are then calculated using the results from Euro NCAP pedestrian impactor tests and injury risk curves. These injury probabilities are converted into cost using “harm”-type costs for the body regions tested. These costs are weighted and summed. Weighting factors were determined using accident data from Germany and Great Britain and an independently estimated AEB benefit. German and Great Britain versions of the methodology are available. The methodology was used to assess cars with good, average, and poor Euro NCAP pedestrian ratings, in combination with a current AEB system. The fitment of a hypothetical A-pillar airbag was also investigated.

Results: It was found that the decrease in casualty injury cost achieved by fitting an AEB system was approximately equivalent to that achieved by increasing the passive safety rating from poor to average. Because the assessment was influenced strongly by the level of head protection offered in the scuttle and windscreen area, a hypothetical A-pillar airbag showed high potential to reduce overall casualty cost.

Conclusions: A benefit-based methodology for assessment of integrated pedestrian protection systems with AEB has been developed and tested. It uses input from AEB tests and Euro NCAP passive safety tests to give an integrated assessment of the system performance, which includes consideration of effects such as the change in head impact location caused by the impact speed reduction given by the AEB.     

Environmental impact of exhaust emissions by Arctic shipping

Since 2005, a dramatic decline of the Arctic sea-ice extent is observed which results in an increase of shipping activities. Even though this provides commercial and social development opportunities, the resulting environmental impacts need to be investigated and monitored. In order to understand the impact of shipping in arctic areas, the method described in this paper determines the travel time, fuel consumption and resulting exhaust emissions of ships navigating in arctic waters. The investigated case studies are considering ship particulars as well as environmental conditions with special focus on ice scenarios. Travel time, fuel consumption and exhaust gas emission were investigated for three different vessels, using different passages of the Northern Sea Route (NSR) in different seasons of years 1960, 2000 and 2040. The presented results show the sensitivity of vessel performance and amount of exhaust emissions to optimize arctic traffic with respect to efficiency, safety and environmental impact.     

Comparing canopy leaf temperature of three Central European tree species based on simultaneous confidence bands for penalized splines

Temperature is an important physical factor that is known to strongly affect biodiversity as well as ecosystems and their functioning. However, research in this area is still relatively limited; this may also be attributed to the multitude of influencing factors and the complexity of the statistics involved. This study analyzes the differences between the surface temperature of three Central European broadleaf tree species. A better understanding of these differences may help to elucidate the role of microclimate in biodiversity. We consider a time series of high-resolution thermal images taken from a meteorological observation tower and calculate mean canopy leaf temperatures for beech, ash and maple (Fagus silvatica, Fraxinus excelsior and Acer pseudoplatanus). In a first step, comparable image areas are extracted from the thermal image sections of the crown of each tree species avoiding shadow areas, branches, etc. We used an automatic segmentation technique, the Otsu thresholding. Extracted canopy leaf temperature values were then processed and the resulting temperature profiles estimated by O’Sullivan penalized splines. For comparing the differences in canopy leaf temperature over time, we propose the construction of simultaneous confidence bands. The analyses show that there are significant—though small—differences in canopy surface temperature between the three tree species.     

Earthworm cast production as a new behavioural biomarker for toxicity testing

There is currently a lack of ecotoxicity tests adapted to earthworm species of higher ecological relevance and whose endpoints could be directly related to their ecological role in the soil. We propose a new and relatively simple ecotoxicity test based on the estimation of cast production (CP) by Lumbricus terrestris under laboratory conditions. CP was found to be linearly correlated to earthworm biomass and to be greatly influenced by soil water content. Azinphos-methyl had no effect on CP at all the concentrations tested. Significant decreases were observed at the normal application rate for other pesticides with (imidacloprid, carbaryl, methomyl) or without (ethyl-parathion and chlorpyrifos-ethyl) a clear concentration-effect response. For the highest concentration tested, reduction in CP varied between 35 and 67%. CP is straightforward and rapidly measured and ecologically meaningful. We thus believe it to be of great use as an endpoint in ecotoxicity testing.     

Implementation of the ecosystem services approach in Swedish municipal planning

While ecosystem-based planning approaches are increasingly promoted through international and national policies, municipalities are still struggling with translating them into practice. Against this background, this paper aims to increase the knowledge of current advances and possible ways to support the implementation of the ecosystem services (ES) approach at the municipal level. More specifically, we analyze how ES have been integrated into comprehensive planning within the municipality of Malmö in Sweden over the last 60 years, a declared forerunner in local environmental governance. Based on a content analysis of comprehensive plans over the period 1956–2014 and interviews with municipal stakeholders, this paper demonstrates how planning has shifted over time toward a more holistic view of ES and their significance for human well-being and urban sustainability. Both explicit and implicit applications of the ES concept were found in the analyzed comprehensive plans and associated programs and projects. Our study shows how these applications reflect international, national, and local policy changes, and indicates how municipalities can gradually integrate the ES approach into comprehensive planning and facilitate the transition from implicit to more explicit knowledge use.     

The championing of environmental improvements in technology investment projects

The literature on environmental champions emphasises the effective action of environmentally committed individuals. This paper draws on case studies of process technology investment projects in chemical and dairy companies in the UK and Sweden. The analysis is based on a political process perspective on organisations. By analysing the career histories of environmental champions as well as their behaviour in the investment projects, the paper shows how their championing behaviour is shaped by dynamic interaction with the organisational context, as well as a broader range of motivations and interests, including career opportunities and private life concerns.     

Hermaphrodite sex role preferences: the role of partner body size, mating history and female fitness in the sea slug Chelidonura sandrana

Costs and benefits associated with matings and the effects of mating frequency on fitness commonly differ between the sexes. As a result, outcrossing simultaneous hermaphrodites may prefer to copulate in the more rewarding sex role, generating conflicts over sperm donation and sperm receipt between mates. Because recent sex role preference models remain controversial, we contrast here some of their assumptions and predictions in the sea slug Chelidonura sandrana. For this hermaphrodite with sperm storage and internal fertilisation, risk-averse models assume that fitness pay-offs are constantly higher in the female than in the male function in any single mating. Moreover, excluding mutual partner assessment, these models predict male mating behaviour to be independent of receiver traits. The competing gender ratio hypothesis assumes that relative fitness pay-offs, and thus the preferred mating roles, vary and may reverse between matings and predicts that ejaculation strategies co-vary with receiver quality. We found that field mating rates of C. sandrana substantially exceeded what is required to maintain female fertility and fecundity, indicating large variation in direct female benefits between matings. We further demonstrate that male copulation duration adaptively increased with partner body size (i.e. fecundity) but decreased with recent partner promiscuity. These findings are compatible with the gender ratio hypothesis but contradict risk-averse models.     

Hereditary Blindness in a Captive Wolf (Canis lupus) Population: Frequency Reduction of a Deleterious Allele in Relation to Gene Conservation

Numerous cases of hereditary diseases and disorders have been reported in wild animals bred in captivity, but little attention has been paid to the particular genetic management problems that arise when such defects occur. These problems include the obstacle of eliminating the deleterious allele(s) without contemporary loss of genetic variability. In this paper we use the statistical methods of pedigree analysis to address questions regarding a previously presumed hereditary form of blindness observed in a captive wolf population bred for conservation purposes in Scandinavian zoos. The most likely mode of inheritance coincides with an autosomal recessive allele with either a full penetrance or a reduced penetrance of 0.6 (depending on the reliability of studbook records). Using these two models of inheritance, we calculate the probability of carrying the blindness allele for each living animal. Analysis of the effect of removing high-probability carriers on founder allele survival and level of inbreeding demonstrates that the frequency of the deleterious allele can be significantly reduced without seriously affecting founder allele survival or current degree of inbreeding in the wolf population.     

Supportive Breeding and Variance Effective Population Size

The practice of supporting weak, wild populations through release of individuals bred in captivity is becoming an increasingly important conservation measure. A frequently recommended form of such breeding-release activity refers to supportive breeding: a fraction of the target population is brought into captivity for reproduction, and the resulting progeny are released to mix with the wild segment of the population. We derived an expression for the variance effective size of a population managed through supportive breeding and discuss its relationship to previously published equations that are based on the assumption of random mating. We show that the effect of supportive breeding may be quite different on the inbreeding and the variance effective sizes. Whereas supportive breeding always results in a reduction of the inbreeding effective number, the variance effective number may either decrease, increase, or remain unchanged. We discuss these observations in relation to conservation management and suggest some general guidelines for supportive breeding situations. Our recommendations include making a distinction between inbreeding and variance effective numbers; taking particular care when dealing with organisms with high reproductive potential; assuring that the amount of drift be no larger than it would be without supportive breeding; and focusing primarily on the variance effective size of a population-that is, on the effective number directly related to the rate of loss of gene diversity.