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关键词： Developmental biology   Stem cells   Nutrition   Hormones  

关键词： Trust in automation   Driving automation   Automation failure   Prior information   Training   Malfunction   ADAPTIVE CRUISE CONTROL   MODEL   PERFORMANCE   ACCEPTANCE   BIAS  

摘要： To prompt the use of driving automation in an appropriate and safe manner, system designers require knowledge about the dynamics of driver trust. To enhance this knowledge, this study manipulated prior information of a partial driving automation into two types (detailed and less) and investigated the effects of the information on the development of trust with respect to three trust attributions proposed by Muir (1994): predictability, dependability, and faith. Furthermore, a driving simulator generated two types of automation failures (limitation and malfunction), and at six instances during the study, 56 drivers completed questionnaires about their levels of trust in the automation. Statistical analysis found that trust ratings of automation steadily increased with the experience of simulation regardless of the drivers' levels of knowledge. Automation failure led to a temporary decrease in trust ratings; however, the trust was rebuilt by a subsequent experience of flawless automation. Results showed that dependability was the most dominant belief of drivers' trust throughout the whole experiment, regardless of their knowledge level. Interestingly, detailed analysis indicated that trust can be accounted by different attributions depending on the drivers' circumstances: the subsequent experience of error-free automation after the exposure to automation failure led predictability to be a secondary predictive attribution of drivers' trust in the detailed group whilst faith was consistently the secondary contributor to shaping trust in the less group throughout the experiment. These findings have implications for system design regarding transparency and for training methods and instruction aimed at improving driving safety in traffic environments with automated vehicles.

关键词： Climate-smart agriculture   Cropland expansion   Deforestation   Zambia   MINIMUM TILLAGE   TROPICAL FORESTS   LAND   INTENSIFICATION   PATTERNS   IMPACT   PRODUCTIVITY   INVESTMENTS   POLICIES   FARMERS  

摘要： There is an urgent need to increase agricultural production in order to meet increasing food demands driven in part by population growth and changing dietary preferences. Doing so by expanding area cultivated into forests has important environmental consequences, including engendering climate change. Climate-smart agriculture (CSA) is considered an important option to increase agricultural productivity and resilience, intensify agricultural production, and possibly reduce cropland expansion. This paper uses nationally representative survey data to assess the extent, intensity and drivers of cropland expansion, and applies an instrumental variable approach to determine the extent to which CSA reduced cropland expansion in Zambia. We find that one-fifth of the 7241 farm households surveyed in 2019 expanded cropland between the 2016/2017 and 2017/2018 farming seasons, clearing on average 0.18 ha, but only 13% expanded their cropland into intact forests, clearing an average of 0.09 ha of forestland per household per year. In aggregate, cropland expansion by smallholder into forests represents about 60% of the estimated 250,000 ha of forests lost per year in Zambia. Most households expanded cropland because they needed to meet subsistence food requirements and a few others in response to market opportunities. We did not find statistically significant associations between adopting CSA and cropland expansion in our national sample. Thus, given the low extent and intensity of CSA adoption as defined in this paper, relying only on CSA as a means to spare forests may be risky. These findings have important implications on CSA practice definition, promotion, framing and adoption.

关键词： Value of travel time   Value of travel time reliability   Road network   Multi-class UE traffic assignment problem   TRAFFIC EQUILIBRIUM-MODEL   RISK-TAKING BEHAVIOR   ROUTE CHOICE   FORMULATION   COVARIANCE   MULTICLASS   CONGESTION   TRANSPORT   DEMANDS   ASSIGNMENT  

摘要： Travel time reliability has been recognized as an important factor in cost-benefit analysis in a transportation network. To estimate the benefit and cost of travel time reliability, several network models have been proposed to estimate the monetary values both of travel time and of travel time reliability based on the driver's route choice behavior. In this study, we propose a network model that addresses monetary values that are specific to each origin-destination pair in a road network. The proposed model is formulated as a utility maximization problem with constraints in a manner similar to studies that address the value of travel time only. The proposed model has the same equilibrium conditions as a multiclass user equilibrium traffic assignment problem with elastic demand in which the risk-averse driver's route choice behavior is explicitly considered. By accounting for data availability, we propose a parameter estimation method based on the maximum likelihood method with two alternative approaches; namely link flow-based and route flow-based approaches. However, the two proposed methods require link flow data only. Numerical experiments are carried out to demonstrate the performance of the two proposed methods together with some insightful findings.

关键词： Automatic vehicle braking   Driver models  

摘要： We propose a new driver braking control model. The driver braking control model is developed based on a ride comfort index. First, a brake model of the experimental vehicle is shown. Next, a driver braking control model is developed by using LQ optimal control. The driver braking control model is designed so that a ride comfort index can become small and ride comfort performance can be improved. Finally, numerical simulations are carried out to show effectiveness of the driver braking control model.

关键词： Driver behaviour   Driver psychology   Latent class   Cluster analysis   Risk factors   ACCIDENT   STRATEGIES  

摘要： Speeding has consistently contributed to a high number of motor vehicle crashes and subsequent injuries and deaths in the U.S. Identifying types of drivers related to speeding behaviour may help target interventions to reduce speeding. Typology of U.S. driver speeders have examined very specifically speeding behaviours and speeding-related attitudes. This exploratory work used latent class analysis (LCA) to examine how other driving behaviours and attitudes cluster around speeding behaviours to determine speeder typologies, which may lend a more holistic perspective to speeder types. Predicted class assignments were evaluated for associations with demographic and personality factors. The LCA resulted in four driver typologies, which we labelled: Externally Motivated (40.7%), Non-Reactors (26.2%), Perceived Invulnerable (24.3%), and Perceived Vulnerable (8.9%). The Externally Motivated and Non-Reactors typologies had the highest probability of reporting extreme speeding. The Externally Motivated may be intervened upon with messaging about reducing risks crashes and injuring passengers, while the Perceived Vulnerable class already exhibit several risk-averse behaviours that self-limits their speeding behaviour. Class placement was associated with age, self-reported speeding frequency, receipt of speeding violations. The resulting U.S. driver typologies advances the literature by demonstrating that non-speeding driver behaviours and attitudes cluster with speeding behaviours, which altogether can inform more nuanced and effective anti-speeding campaigns.

关键词： Energy trilemma   Energy use   Financial development   Economic growth   Top ten countries of the WETI 2020   RENEWABLE ENERGY   CONSUMPTION   SECURITY   DYNAMICS   MODEL  

摘要： Economic growth can increase the economy's energy intensity, impeding security through unmanaged demand and affecting sustainability. This study employed energy use, population growth, and financial development from 1990 to 2016 as moderator variables to examine the impact of energy trilemma on the economic growth of the top ten countries in the World Energy Trilemma Index (WETI) 2020. We applied advanced econometric methodologies for empirical analysis, such as second-generation panel unit root tests, and cross-section dependence. Besides, we used the random-effect and fixed effect panel generalized method of moments (GMM) for short-run estimates and the random effect and fixed effect generalized least squares (GLS) regressions and robust fully modified least squares (FMOLS) regression for the long-run estimates. The results indicate that the impact of energy trilemma and population growth on economic growth are significant only in the long-run, while energy use and financial development influence economic growth in both the short-run and the long-run. Our findings suggest that policymakers implement lesser potential for Pareto perfections in the energy system by levying energy security, affordability, and sustainability taxes on energy products, and that they highlight energy efficiency and support robust policies to enhance financial development. Study limitations and directions for future research in the area are discussed.

关键词： Disaster   Amphan   Resilience   Risk   Hazards   Cyclone  

摘要： Disaster like the supercyclone Amphan which devastated the states of West Bengal and Odisha in India caused severe disruption to the life, and led to widespread economic losses which surpassed the proficiency of the society to overcome with sustenance from its own assets. The main prospect for disaster risk reduction lies in decreasing susceptibility and exposure to such hazards. In our study, we targeted identification and lessening the factors driving the risk, to understand risks of hazards such as Amphan. Thereafter, we explained the pathways of understanding disaster risks and ways of building resilience involving every section of society, government, nongovernmental organizations including the private sector which may influence sustainable development. We summarized that disaster mitigation required a people-oriented multi-sector methodology which may help build resilience to manifold, surging and interrelating hazards and generating principles of deterrence and resilience through all societal sections. The developmental plan of actions discussed to ensure disaster resilience, needs to permeate through all societal levels including the financial structure, risk-sharing strategies and social safety device mechanisms. Significant prospects to achieve synergies between actions intended to strengthen resilience may help to achieve progress towards the achievement of disaster risk reduction. Understanding the risk of a disaster like Amphan, developing resilience against it to create sustainable development had not been explored previously. The paper reported insight into the ways adapted by central & state government and the local bodies to reduce the risk and build resilience against a disaster like Amphan.

关键词： nitrification   denitrification   N fertilizer   N2O emission   soil water content   plant presence   GREENHOUSE-GAS EMISSIONS   N2O EMISSIONS   NITRIFIER DENITRIFICATION   NO EMISSIONS   CH4 FLUXES   SOIL CO2   FERTILIZER   SYSTEMS   IMPACT   NITRIFICATION  

摘要： There is a need for long-term data on N2O emission in Central Europe to provide a thorough understanding of the variability of the emission processes as affected by different biotic and abiotic drivers. It could be helpful for national greenhouse gas inventories and also for revealing potential ways of mitigation. In order to describe temporal variability of soil N2O emission under varying key conditions, a field experiment was carried out at a cropland site on loamy and clay loamy Chernozems in Central Hungary. Dynamics of N2O emissions were observed bi-weekly during a two-year-long study (November 2017-November 2019) using a static closed chamber-gas chromatographic method. Additional variables, including soil water content, soil temperature, leaf area index, vegetation index and net ecosystem exchange of CO2 were also measured. Besides, a laboratory pot experiment was conducted focusing on the role of soil water content, N fertilizer, and plant presence on soil N2O emissions. Average field N2O emissions during the study period varied between 0.27 and 29.94 mu g N m(-2) h(-1) with the largest emission peaks measured following the freeze-thaw cycle during wintertime. Additional N2O emission peaks were observed following applications of N fertilizer and at high soil water content. Significant positive correlations were found between field N2O emission and both soil water content and vegetation index. In contrast, a negative relationship was found between N2O emission and soil temperature. Similar pattern was observed in the pot experiment with a significant positive correlation between N2O emissions and soil water content when neither soil nitrate content nor temperature were limiting for microbial denitrification. In addition, a significant correlation between N2O emission and fertilizer rate was revealed at the soil water content higher than 30% both in bare and planted soil. However, variations in soil N2O emission among the treatments were not significantly corr