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1.
Replacing conventional vehicle taxis with electric vehicles would be an efficient measure to reduce greenhouse gas emissions. Due to the limited range and long charging times of current battery electric vehicles, it is of utmost importance to provide sufficient charging facilities. This article analyses the impact of the placement and charging power of charging stations on potential mileage and revenue of electric taxis on the example of Singapore. Therefore, we developed an agent-based electric taxi simulation model to investigate electric taxis’ driving profiles with respect to different vehicle types and charging infrastructure designs. This model is also capable of simulating conventional taxi driving profiles. The validation of these simulation results with real taxi data showed that the model is reproducing taxi driving profiles with high accuracy in great detail. We found out that electric taxis could reach the same mileage and revenue as conventional taxis if charging with a power of 160?kW is possible. Furthermore, we discovered that waiting times for available charging stations have a stronger effect on revenue than the length of detours to reach charging stations. Based on these findings, we concluded that it is more important to reduce waiting times by placing sufficient numbers of charging stations at each location before expanding the charging network by installing small numbers of charging stations at many locations.  相似文献   
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Sapir  André  Schraepen  Tom  Tagliapietra  Simone 《Intereconomics》2022,57(3):175-178
Intereconomics - Public procurement amounts to around 14% of European Union GDP and, given this size, could well represent an important tool to foster the green transition. However, green public...  相似文献   
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Review of Quantitative Finance and Accounting - We investigate the firms’ specific attributes that determine the difference in speed of adjustment (SOA) towards the cash holdings target in...  相似文献   
5.
Many wildlife tourist attractions (WTAs) have negative impacts on animal welfare and species conservation. In the absence of regulation, raising standards requires tourists to create market pressure by choosing to attend WTAs with benefits for wildlife. We surveyed respondents from five countries – China, Australia, Canada, UK, and USA – to quantify how attitudes to captive animals, and towards WTAs’ outputs and standards, may vary with nationality. Our aim was to provide a firm basis for behaviour change interventions to alter current patterns of tourist consumption of WTAs. All respondents agreed on the importance of conservation and animal welfare, but Chinese respondents were twice as likely to believe that WTAs would not be allowed to exist if they were bad for animals, and that WTAs’ promotional materials were reliable indicators of welfare and conservation standards. These findings indicate Chinese respondents had fundamentally similar attitudes to those from the other countries, but differed in how those attitudes were likely to be applied. Chinese tourists may experience more barriers to aligning their actions with their values with respect to WTAs. Removing these barriers may require information campaigns to highlight the lack of regulation, and the unreliability of some WTAs’ promotional materials and tourists’ reviews.  相似文献   
6.
Meta-analysis has become the conventional approach to synthesizing the results of empirical economics research. To further improve the transparency and replicability of the reported results and to raise the quality of meta-analyses, the Meta-Analysis of Economics Research Network has updated the reporting guidelines that were published by this Journal in 2013. Future meta-analyses in economics will be expected to follow these updated guidelines or give valid reasons why a meta-analysis should deviate from them.  相似文献   
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Fisheries management is characterised by multiple objectives, some of which may be complementary, while others may require trade‐offs between outcomes. Balancing these objectives is made more complex in the case of multispecies and multigear fisheries. In this paper, we develop a bioeconomic model that captures the key elements of such a fishery to test a range of potential harvest strategies to provide insights into how economic target reference points could lead to both desirable and undesirable management outcomes (e.g. discards). The model is developed as a long‐run optimisation model to identify target reference points to achieve multispecies maximum economic yield, and a dynamic recursive optimisation model, which includes more realistic representation of fishers’ behaviour, such as discards and trading of under‐caught species quotas. The potential economic, social and ecological impacts are evaluated using data envelopment analysis (DEA). The results suggest that the use of proxy target reference points can result in short‐term economic benefits at the cost of slower stock recovery and higher discarding. Limiting the number of species subject to quota controls may also prove beneficial in multispecies fisheries, while ensuring quota markets are efficient is likely to produce benefits irrespective of the harvest strategy adopted.  相似文献   
8.
The general consensus in the volatility forecasting literature is that high-frequency volatility models outperform low-frequency volatility models. However, such a conclusion is reached when low-frequency volatility models are estimated from daily returns. Instead, we study this question considering daily, low-frequency volatility estimators based on open, high, low, and close daily prices. Our data sample consists of 18 stock market indices. We find that high-frequency volatility models tend to outperform low-frequency volatility models only for short-term forecasts. As the forecast horizon increases (up to one month), the difference in forecast accuracy becomes statistically indistinguishable for most market indices. To evaluate the practical implications of our results, we study a simple asset allocation problem. The results reveal that asset allocation based on high-frequency volatility model forecasts does not outperform asset allocation based on low-frequency volatility model forecasts.  相似文献   
9.
ABSTRACT

Unemployment durations vary across local authority districts in the UK. We explore the extent to which this variation is explained by differences in local labour demand as opposed to composition, business cycle and regional effects. We use seventeen waves of the British Household Panel Survey to identify the determinants of the duration of unemployment spells. Once we adjust for individual-level, business cycle and regional controls, we do not find evidence that living in a local authority district with relatively high unemployment is associated with longer spells of unemployment. This indicates that differences in labour demand operate at larger geographic scales, such as between large regions. Our findings have implications for the design of policies to help high unemployment districts.  相似文献   
10.
If teachers are not equipped to teach Technology Education subject nationally and internationally, the continent of Africa will continue to bear the brunt of unsavoury results unless radical interventions are implemented to transform the situation. It is against this background that action research methods became a useful site-based support to empower Technology teachers at three sampled schools from Tshwane South Circuit in Gauteng Province of South Africa. The purpose of this study was to share fresh perspectives on how a sample of Technology teachers responded to content-related classroom practices during reflective action research activities that took place during community engagement contact sessions. These teachers, who are under qualified and unqualified to teach this subject, were engaged in circular and spiral action research cycles. The teachers’ engagement brought forth the development of Technology Education Cascading Theory. It was evident that community engagement activities served as a podium to transform teachers’ teaching of Technology Education and enhance learners’ achievement. The study was underpinned by cooperative enquiry theory and engaged participants in reflective practices of developmental action paradigm. Interaction with Technology Education teachers further revealed that most of them need their schools to budget for this Technology subject they are teaching.  相似文献   
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