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61.
ABSTRACT

The benefits of biofuels depend on the feedstock, conversion pathway and local context. This paper assesses biofuels technology readiness and developments to provide foresight to biofuels development in Southern Africa. Efficient conversion pathways, coupled with biomass from waste or high-yielding energy crops, will reduce both the costs of biofuels production, and the environmental impacts. Compared to petroleum fuels, the current commercial biofuels (ethanol, biogas and biodiesel) typically offer carbon emission reductions of 30–50% but are marginally more expensive. The extent of biofuels market penetration will therefore be influenced by mandates (blending targets) and subsidies (green premium). Advanced biofuels promise greater efficiencies and carbon emission reductions at reduced cost but will require further research and development to reach commercialisation. If developed appropriately, biofuels can reduce carbon emissions and improve energy security, while enabling sustainable agriculture and improved natural resources management.  相似文献   
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After‐tax income inequality has risen since the mid‐1990s, as increases in market income inequality have not been offset by greater fiscal redistribution. We argue that the substantial increase in the diversity of consumer goods has mitigated mounting political pressures for redistribution. Within a probabilistic voting framework, we demonstrate that if the share of diversified goods in the consumption bundle increases sufficiently with income, then an increase in goods diversity can reduce the political equilibrium tax rate. Focusing on OECD countries, we find empirical support for both the model's micro‐political foundations and the implied relation between goods diversity and fiscal policy outcomes.  相似文献   
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Abstract

Unsignalized intersections in developing countries experience many serious conflicts between cross-traffic due to indiscipline traffic manoeuvrability. Historically, Post Encroachment Time (PET) has gained attention as a proximal indicator to analyze crossing conflicts. However, identifying an appropriate PET threshold to classify critical conflicts for highly heterogeneous traffic scenario is still an unexplored area. Consequently, this study proposes a novel approach of PET threshold identification with proof of application by collecting data from ten intersections located on four-lane intercity highways in the National Capital Region (NCR), India. Both crossing conflicts and right-turn related crash data (for the left-hand drive) are collected. Their correlations are thoroughly studied for each PET threshold using a quantitative technique considering all and individual vehicle categories. Finally, a qualitative analysis is done by ranking the sites based on cumulative PET and related crashes to verify the proposed quantitative technique. A PET threshold of 1?s is obtained from both the techniques which can be used to identify critical conflicts for unsignalized intersections located on four-lane intercity highways. The proposed methodology will serve as an alternative, faster and effective tool to evaluate the hazardousness of unsignalized intersections located on intercity highways under highly heterogeneous traffic condition.  相似文献   
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Research on location-based advertising (LBA) suggests that the merits of LBA lie in the fact that consumers can be targeted with location-congruent ads on their personal mobile devices. However, LBA consists of two underlying constructs: a mobile (vs. point-of-sales) advertising medium and location congruency (vs. location incongruency). This study aims to disentangle these underlying constructs by showing that they differentially affect the efficacy of an ad. Using a virtual reality lab experiment, this study shows that location-congruent ads result in increased choice for the target brand as compared to location-incongruent ads, independent of medium type. However, in location-incongruent situations, mobile ads attracted more attention than point-of-sales display ads. The advantages of LBA thus do not seem to emanate from medium type, but rather from the congruency between the ad and product location. When the ad is received at a different location than the product, the mobile medium is able to enhance consumers' ad attention.  相似文献   
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ABSTRACT

This article discusses some of the issues regarding the first employees to work in a space hotel. As space hotels initially will be vastly different to existing hotels on Earth, it is important to question what human resource challenges this will raise for hospitality workers and providers. To assist reflection on this issue, the notions of space tourism and space tourist are explored, and a definition of a space hotel is included to create product and service boundaries. Plausible futures methodology is used to create five main human resource considerations and concludes by suggesting this sector is largely unexplored.  相似文献   
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This article reports the findings of a study, conducted among 234 foreign tourists who visited Cyprus, that aimed to identify the drivers and outcomes of eco‐friendly attitudes and behavior. Using structural equation modeling, the authors confirmed that deontological status, law obedience, and political action of tourists positively influence the adoption of an environmentally friendly attitude. In turn, these effects are conducive to eco‐friendly behavior, which ultimately enhances tourist satisfaction. Certain sociodemographic characteristics of tourists—namely, gender, age, education, and income—had a moderating effect on the link between deontological status, law obedience, and political action on the one hand and eco‐friendly attitudes on the other hand. Tourist nationality also had a control effect on tourist eco‐friendly attitudes.  相似文献   
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