Pub Date : 2020-04-27DOI: 10.15587/1729-4061.2020.200664
V. Popov, V. Loginov, Volodymyr Shmyrov, Yevgen Ukrainets, Petro Steshenko, Pavlo A. Hlushchenko
Improving the aircraft’s fuel efficiency is one of the main requirements for prospective and modernized aircraft. This paper reports the assessment of change in aerodynamic quality resulting in the improved fuel efficiency of a long-range aircraft when using promising means to enhance aerodynamic quality. These means include the abandonment of the mechanization of wing edges and conventional controls through the use of an adaptive wing, the artificial laminarization of the flow around the elements of a glider, the application of winglets. The abandonment of conventional wing controls and wing mechanization is predetermined by the need to ensure a seamless surface of the glider elements to prevent the premature turbulization of the flow that consequently leads to a decrease in the profile drag of an aircraft. The use of winglets is aimed at reducing inductive drag. Determining a change in the aircraft’s fuel efficiency would make it possible to estimate a change in the operating costs during its life cycle. The study employed the known modular software complex «Integration 2.1». The engineering and navigational calculation was performed for a typical flight profile of a long-range aircraft. The possibility of reducing fuel consumption by up to 20 % has been shown. The largest impact on the decrease in fuel consumption is exerted by the flow laminarization on the surface of the glider elements; the reduction in fuel consumption was 17.1 %. The abandonment of mechanization and ailerons decreases fuel consumption by 3.9 %, while the abandonment of ailerons, slats, and flaps reduces fuel consumption by 0.4, 1.5, and 0.4 %, respectively. The use of spiroid winglets made it possible to reduce fuel consumption by 1.95 %
{"title":"Improving Aircraft Fuel Efficiency by Using the Adaptive Wing and Winglets","authors":"V. Popov, V. Loginov, Volodymyr Shmyrov, Yevgen Ukrainets, Petro Steshenko, Pavlo A. Hlushchenko","doi":"10.15587/1729-4061.2020.200664","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.200664","url":null,"abstract":"Improving the aircraft’s fuel efficiency is one of the main requirements for prospective and modernized aircraft. This paper reports the assessment of change in aerodynamic quality resulting in the improved fuel efficiency of a long-range aircraft when using promising means to enhance aerodynamic quality. These means include the abandonment of the mechanization of wing edges and conventional controls through the use of an adaptive wing, the artificial laminarization of the flow around the elements of a glider, the application of winglets. The abandonment of conventional wing controls and wing mechanization is predetermined by the need to ensure a seamless surface of the glider elements to prevent the premature turbulization of the flow that consequently leads to a decrease in the profile drag of an aircraft. The use of winglets is aimed at reducing inductive drag. Determining a change in the aircraft’s fuel efficiency would make it possible to estimate a change in the operating costs during its life cycle. The study employed the known modular software complex «Integration 2.1». The engineering and navigational calculation was performed for a typical flight profile of a long-range aircraft. The possibility of reducing fuel consumption by up to 20 % has been shown. The largest impact on the decrease in fuel consumption is exerted by the flow laminarization on the surface of the glider elements; the reduction in fuel consumption was 17.1 %. The abandonment of mechanization and ailerons decreases fuel consumption by 3.9 %, while the abandonment of ailerons, slats, and flaps reduces fuel consumption by 0.4, 1.5, and 0.4 %, respectively. The use of spiroid winglets made it possible to reduce fuel consumption by 1.95 %","PeriodicalId":210650,"journal":{"name":"EnergyRN: Transportation (Sub-Topic)","volume":"334 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116906930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Using staggered entry of two dockless bikesharing firms, we find the entrant expands the market for the incumbent. The entry helps the incumbent to serve a greater number of trips, make more bike investment, achieve higher revenue per trip, improve bike utilization rate, and form a wider and more evenly distributed network. The market expansion effect on new users dominates a significant marketstealing effect on old users. These findings, together with a theoretical model that highlights consumer search and network effects, suggest that a market with positive network effects is not necessarily winnertakesall, especially when users multihome across compatible networks.
{"title":"Market Expanding or Market Stealing? Competition with Network Effects in Bikesharing","authors":"Guangyu Cao, G. Jin, Li-an Zhou","doi":"10.3386/W24938","DOIUrl":"https://doi.org/10.3386/W24938","url":null,"abstract":"Using staggered entry of two dockless bikesharing firms, we find the entrant expands the market for the incumbent. The entry helps the incumbent to serve a greater number of trips, make more bike investment, achieve higher revenue per trip, improve bike utilization rate, and form a wider and more evenly distributed network. The market expansion effect on new users dominates a significant marketstealing effect on old users. These findings, together with a theoretical model that highlights consumer search and network effects, suggest that a market with positive network effects is not necessarily winnertakesall, especially when users multihome across compatible networks.","PeriodicalId":210650,"journal":{"name":"EnergyRN: Transportation (Sub-Topic)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130353803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Economists often favour market-based mechanisms over non-market based mechanisms to allocate scarce public resources on grounds of economic efficiency and revenue generation. When the usage of the resources in question generates type-dependent negative externalities, the welfare comparison can become ambiguous. Both types of allocation mechanisms are being implemented in China's major cities to distribute limited vehicle licences as a measure to combat worsening traffic congestion and air pollution. While Beijing employs non-transferable lotteries, Shanghai uses an auction system. This article empirically quantifies the welfare consequences of the two mechanisms by taking into account both allocation efficiency and automobile externalities post-allocation. Our analysis shows that different allocation mechanisms lead to dramatic differences in social welfare. Although Beijing's lottery system has a large advantage in reducing automobile externalities over auction, the advantage is offset by the significant allocative cost from misallocation. The lottery system in Beijing resulted in a social welfare loss of 30 billion Yuan (nearly $5 billion) in 2012 alone. A uniform-price auction would have generated nearly 20 billion Yuan to Beijing municipal government, more than covering all its subsidies to the local public transit system.
{"title":"Better Lucky Than Rich? Welfare Analysis of Automobile License Allocations in Beijing and Shanghai","authors":"Shanjun Li","doi":"10.2139/ssrn.2349865","DOIUrl":"https://doi.org/10.2139/ssrn.2349865","url":null,"abstract":"Economists often favour market-based mechanisms over non-market based mechanisms to allocate scarce public resources on grounds of economic efficiency and revenue generation. When the usage of the resources in question generates type-dependent negative externalities, the welfare comparison can become ambiguous. Both types of allocation mechanisms are being implemented in China's major cities to distribute limited vehicle licences as a measure to combat worsening traffic congestion and air pollution. While Beijing employs non-transferable lotteries, Shanghai uses an auction system. This article empirically quantifies the welfare consequences of the two mechanisms by taking into account both allocation efficiency and automobile externalities post-allocation. Our analysis shows that different allocation mechanisms lead to dramatic differences in social welfare. Although Beijing's lottery system has a large advantage in reducing automobile externalities over auction, the advantage is offset by the significant allocative cost from misallocation. The lottery system in Beijing resulted in a social welfare loss of 30 billion Yuan (nearly $5 billion) in 2012 alone. A uniform-price auction would have generated nearly 20 billion Yuan to Beijing municipal government, more than covering all its subsidies to the local public transit system.","PeriodicalId":210650,"journal":{"name":"EnergyRN: Transportation (Sub-Topic)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125351891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Infrastructure finance has been much discussed recently. We first present a brief argument about the importance of establishing what we call the Wicksellian Connection – a clear and meaningful linkage between expenditures and revenues – essentially because unless it is decided who is going to pay for infrastructure and how, we cannot sensibly decide what should be done. In the next section we then review the major proposals that have been put forward on financing rapid transit in the Toronto region, and find that little attention has been paid to establishing a sufficiently clear linkage between what is to be done and how it is to be paid to ensure that what is finally done is financed in a way that will meet even the barest tests of efficiency, equity, and accountability. Finally, a brief conclusion considers some ways in which this circle may be closed and at least a partial Wicksellian Connection established.
{"title":"Financing Regional Public Transit in Ontario: The Case for Strengthening the Wicksellian Connection","authors":"E. Slack, R. Bird","doi":"10.2139/SSRN.2642438","DOIUrl":"https://doi.org/10.2139/SSRN.2642438","url":null,"abstract":"Infrastructure finance has been much discussed recently. We first present a brief argument about the importance of establishing what we call the Wicksellian Connection – a clear and meaningful linkage between expenditures and revenues – essentially because unless it is decided who is going to pay for infrastructure and how, we cannot sensibly decide what should be done. In the next section we then review the major proposals that have been put forward on financing rapid transit in the Toronto region, and find that little attention has been paid to establishing a sufficiently clear linkage between what is to be done and how it is to be paid to ensure that what is finally done is financed in a way that will meet even the barest tests of efficiency, equity, and accountability. Finally, a brief conclusion considers some ways in which this circle may be closed and at least a partial Wicksellian Connection established.","PeriodicalId":210650,"journal":{"name":"EnergyRN: Transportation (Sub-Topic)","volume":"72 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133530551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-04-20DOI: 10.24924/IJABM/2015.04/V3.ISS1/92.107
Yousif, Zubair Hassan
The purpose of this study is identifying the customer perceived value associated with automobile and examining its impact on customer satisfaction and brand loyalty. A sample size of 198 respondents was chosen from various points in Jeddah, Saudi-Arabia using convenient sampling. A multi-factor CPV questionnaire with a Likert-Scale from 1-5 was used to collected the data to determine customer perceived value associated with automobile and its impact on customer satisfaction and brand loyalty. To ensure reliability and validity of the data set, sample size only includes respondents who have been using/driving an automobile for a year. Descriptive statistics shows that the most significant perceived value associated with automobile is functional value followed by emotional value and epistemic value. Social value was the least reason that respondents purchase an automobile. In terms of correlations, this study found that overall customer perceived value associated with automobile is highly correlated with customer satisfaction and brand loyalty. Bivariate multiple regression analysis shows that there is a significant and positive impact of FV and CV on customer satisfaction. We do not find any significant influence of EV, EPV and SV on customer satisfaction. However we found that there is a significant and positive impact of EV, FV and CV on customer brand loyalty. Again we did not find any significant impact of SV and EPV on brand loyalty. The current study contributes to the body of research by investigating the combined impacts of customer perceived value on automobiles using one instrument on cross-sectional setting. This research shows that customer perceived value associated with automobile is crucial in increasing customer satisfaction and brand loyalty. Future research should be undertaken on different context or by increasing the sample size by widening the research context to ensure validity and reliability of the results
{"title":"Customer Perceived Values Associated with Automobile and Brand Loyalty","authors":"Yousif, Zubair Hassan","doi":"10.24924/IJABM/2015.04/V3.ISS1/92.107","DOIUrl":"https://doi.org/10.24924/IJABM/2015.04/V3.ISS1/92.107","url":null,"abstract":"The purpose of this study is identifying the customer perceived value associated with automobile and examining its impact on customer satisfaction and brand loyalty. A sample size of 198 respondents was chosen from various points in Jeddah, Saudi-Arabia using convenient sampling. A multi-factor CPV questionnaire with a Likert-Scale from 1-5 was used to collected the data to determine customer perceived value associated with automobile and its impact on customer satisfaction and brand loyalty. To ensure reliability and validity of the data set, sample size only includes respondents who have been using/driving an automobile for a year. Descriptive statistics shows that the most significant perceived value associated with automobile is functional value followed by emotional value and epistemic value. Social value was the least reason that respondents purchase an automobile. In terms of correlations, this study found that overall customer perceived value associated with automobile is highly correlated with customer satisfaction and brand loyalty. Bivariate multiple regression analysis shows that there is a significant and positive impact of FV and CV on customer satisfaction. We do not find any significant influence of EV, EPV and SV on customer satisfaction. However we found that there is a significant and positive impact of EV, FV and CV on customer brand loyalty. Again we did not find any significant impact of SV and EPV on brand loyalty. The current study contributes to the body of research by investigating the combined impacts of customer perceived value on automobiles using one instrument on cross-sectional setting. This research shows that customer perceived value associated with automobile is crucial in increasing customer satisfaction and brand loyalty. Future research should be undertaken on different context or by increasing the sample size by widening the research context to ensure validity and reliability of the results","PeriodicalId":210650,"journal":{"name":"EnergyRN: Transportation (Sub-Topic)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130394926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The U.S. public transit system represents a multi-billion dollar industry that provides essential transit services to millions of urban residents. We study the market for new transit buses that features a set of non-profit transit agencies purchasing buses primarily from a few domestic bus makers. In contrast with private passenger vehicles, the fuel economy of public buses has not improved during the last thirty years and is irresponsive to fuel price changes. To understand these findings, we build a model of bus fleet management decisions of public transit agencies that yields testable hypotheses. Our empirical analysis of bus fleet turnover and capital investment highlights the role of energy prices, environmental regulations, and the “Buy America” mandate associated with receiving federal funding to purchase public transit buses.
{"title":"Public Transit Bus Procurement: the Role of Energy Prices, Regulation and Federal Subsidies","authors":"Shanjun Li, Matthew E. Kahn, Jerry Nickelsburg","doi":"10.2139/ssrn.2393806","DOIUrl":"https://doi.org/10.2139/ssrn.2393806","url":null,"abstract":"The U.S. public transit system represents a multi-billion dollar industry that provides essential transit services to millions of urban residents. We study the market for new transit buses that features a set of non-profit transit agencies purchasing buses primarily from a few domestic bus makers. In contrast with private passenger vehicles, the fuel economy of public buses has not improved during the last thirty years and is irresponsive to fuel price changes. To understand these findings, we build a model of bus fleet management decisions of public transit agencies that yields testable hypotheses. Our empirical analysis of bus fleet turnover and capital investment highlights the role of energy prices, environmental regulations, and the “Buy America” mandate associated with receiving federal funding to purchase public transit buses.","PeriodicalId":210650,"journal":{"name":"EnergyRN: Transportation (Sub-Topic)","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114154251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The concept that exporters learn from their exporting experience is a theoretical result that needs to be tested empirically. However, the literature provides mixed evidence. In this paper, to estimate productivity, an approach suggested by De Loecker is applied, which corrects for econometric and consistency problems. Using a dataset for the Chinese automobile between 1998 and 2007, no evidence of learning by exporting was found. The data also suggests explanations for why it does not support this hypothesis.
{"title":"Does Learning by Exporting Happen? Evidence from the Automobile Industry in China","authors":"T. Luong","doi":"10.1111/rode.12043","DOIUrl":"https://doi.org/10.1111/rode.12043","url":null,"abstract":"The concept that exporters learn from their exporting experience is a theoretical result that needs to be tested empirically. However, the literature provides mixed evidence. In this paper, to estimate productivity, an approach suggested by De Loecker is applied, which corrects for econometric and consistency problems. Using a dataset for the Chinese automobile between 1998 and 2007, no evidence of learning by exporting was found. The data also suggests explanations for why it does not support this hypothesis.","PeriodicalId":210650,"journal":{"name":"EnergyRN: Transportation (Sub-Topic)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115320987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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