While all relational database systems are based on the bag data model, much of theoretical research still views relations as sets. Recent attempts to provide theoretical foundations for modern data management problems under the bag semantics concentrated on applications that need to deal with...
01a Articolo in rivista
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This paper aims to analyze overall economic and environmental performances of alternative bus powertrains by focusing on U.S. active fleets in different urban contexts. We define a life cycle cost model related to bus technologies by referring to real-world data of 256 transport operators, which...
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In this article, we contribute to the scant literature covering quantitative studies on the determinants of the non-academic staff incidence in higher education institutions by analysing how the proportion of non-academic staff is related to key features such as size, prestige, year of foundation...
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We study the effects of the deregulation of intercity bus services in Europe on intermodal competition in long-distance land passenger transport and on social welfare. We consider a bus company with a flexible (Internet-based) business model and a rail operator with a rigid cost structure due to...
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Airport runways, radio spectrum, and hospital beds are resources with capacity limits used to provide multiple services with specific capacity requirements in separate markets, which contribute to recover capacity investment costs. A welfare-maximizing and (possibly) budget-constrained firm, whose...
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When comparing the cost structure of different transport operators, tools standardising the expenses an ideal efficient operator would incur in producing a specific transport service are valuable instruments for private companies and public authorities. In this paper, we build a bottom-up cost...
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Local public transport (LPT) operators typically operate at a deficit and require economic compensation from public authorities. In some countries, public funds are provided both at a national (centralized) level and at a regional (decentralized) level. Thus, a proper distribution of such funds...
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In the last years, several Italian legislative interventions concerning the local public transport (LPT) sector aimed at inducing Local Authorities to re-programming the current services by changing the existing transport modes in favor of less expensive ones, while preserving passengers mobility....
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In this paper, we build a proxy cost model for tramway services. we estimate separately: (i) transport services production costs; (ii) infrastructure costs; (iii) maintenance costs; (iv) administrative and general costs and (v) the cost of capital. we apply the proposed methodology to estimate the...
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The paper estimates the standard cost in Italian regional public rail passenger transport services (LPTR), depending on service characteristics. The results highlight the crucial role of: number of seats per ride, commercial speed, service size and length of rail tracks. The model also shows the...