Search results for "Arity"
showing 10 items of 2893 documents
The effect of cooperative infrastructure fees on high-speed rail and airline competition
2021
Abstract This paper explores the effects of cooperation between rail and air infrastructures in setting per-passenger fees prior to competition among airlines and high-speed rail (HSR) in a transport network. It is shown that, for a sufficiently low degree of substitution, cooperation results in lower fees and greater HSR traffic than under competition. Besides, it leads to more connecting passengers. An empirical application allows for a quantitative assessment of cooperation. Gains to passengers and operators are sizeable when cooperation either involves all infrastructure managers or the rail and the hub airport managers. Welfare gains are in the range of 10.4–11.1%. Our contribution off…
Crowdfunding in Africa: Opportunities and Challenges
2020
AbstractThe chapter presents the current state of crowdfunding research and practice in Africa while outlining opportunities and challenges associated with them. Conditions of growing popularity of digital and mobile finance, low penetration of traditional financial institutions, and a long cultural heritage of communal mutual support may enhance crowdfunding uptake. On the other hand, conditions of unclear regulation, relatively low levels of internet access, and societies characterized by low social trust may all hinder crowdfunding uptake. Accordingly, African crowdfunding is at its infancy and involves transitory hybrid practices of early adoption, often involving reliance on foreign co…
Sustainable development goals research in higher education institutions: An interdisciplinarity assessment through an entropy-based indicator
2022
Since 2015, the United Nations has urged higher education institutions (HEIs) to adopt an interdisciplinary approach towards the Sustainable Development Goals (SDGs). In other words, universities are encouraged to transcend any single disciplinary perspective in exploring sustainable development issues. This study examines the importance of driving the scientific production of HEIs towards the SDGs as a concrete institutional contribution to sustainable development. While bibliometric tools for the SDGs are currently emerging, the existing models have not focused on interdisciplinarity or on their usefulness as decision-management tools to drive SDG-related research at a micro-scale (i.e. t…
Crowdfunding Models, Strategies, and Choices Between Them
2020
AbstractThe growing popularity of crowdfunding is manifested through the proliferation of thousands of platforms globally. The current chapter presents an elaborate, up-to-date, and detailed typology of crowdfunding models currently in use, as well as their main characteristics. Furthermore, it suggests some of the first frameworks developed for guiding prospective fundraisers in choosing between models. Each of the frameworks is designed for a different type of fundraiser, including model choice heuristics for organizations and consumers. The chapter concludes with some suggestions for further research and implications for practice.
A new series of π-extended tetrathiafulvalene derivatives incorporating fused furanodithiino and thienodithiino units: a joint experimental and theor…
2004
A new family of tetrathiafulvalenes has been prepared. The materials exhibit complex redox behaviour related to the electronic influence of the 1,4-dithiin moieties embedded within the framework of the molecules. The X-ray crystal structure of compound 4 reveals an unusual non-planar conformation of the heterocyclic compound, with the TTF fragment adopting a boat conformation. Theoretical calculations, performed at the DFT level (B3P86/6-31G*), confirm the boatlike structure (C2v symmetry) as the most stable conformation for this family of tetrathiafulvalenes. Upon oxidation, electrons are extracted from the whole molecule and the radical cations and dications remain highly distorted from p…
Structural and magnetic properties of the solid solution series Sr2Fe1–xMxReO6(M = Cr, Zn)
2005
Strong correlations between the electronic, structural and magnetic properties have been found during the study of doped double perovskites Sr2Fe1−xMxReO6 (0 ≤ x ≤ 1, M = Zn, Cr). The interplay between the van Hove singularity and the Fermi level plays a crucial role for the magnetic properties. Cr doping of the parent compound Sr2FeReO6 leads to a non-monotonic behaviour of the saturation magnetization and an enhancement for doping levels up to 10%. The Curie temperatures monotonically increase from 401 to 616 K. In contrast, Zn doping leads to a continuous decrease in the saturation magnetization and the Curie temperatures. Superimposed on the electronic effects is the structural influenc…
Valence instabilities and inhomogeneous mixed valence in some ternary europium compounds
1997
Abstract Photoemission spectra and TB-LMTO-ASA band structure calculations of some mixed valency europium compounds hve been studied. The band structures are compared with the band structures of the isostructural lanthanum and strontium compounds. Surprisingly a 4f density of states in the vicinity of the Fermi level is observed in inhomogenous mixed valency EuPd 3 B, Eu 3 S 4 , and EuPdP. Indeed a van Hove Singularity (vHS) derived from the d states of La and Pd or p states of boron or phosphorous are found in La 3 S 4 , LaPd 3 B and SrPdP. The valence instability in the Eu compounds is thus not necessarily due to Eu 4f states. The results also provide some ground for the assumption that i…
COVID-19 and orientations towards solidarity: the cases of Spain, Hungary, and Romania
2020
Solidarity is core to Europe's societal organisation and was intensively addressed in recent research. Using data collected before and during the lockdown in spring 2020, we examine whether value o...
What determines the willingness to sanction violations of newly introduced social norms: Personality traits or economic preferences? evidence from th…
2021
Abstract Social norms govern human behavior and usually change slowly over time. While individuals’ willingness to sanction others is decisive for the enforcement of social norms and thus social stability, little is known about individual sanctioning behavior related to newly introduced social norms. During the COVID-19 pandemic, governments have used various tools to rapidly and actively introduce the new norm of wearing a face mask; this offers a unique setting to study the determinants of individuals’ willingness to sanction a cooperation norm. In a nationwide online survey in Germany, we find that higher levels of conscientiousness and neuroticism, but none of the economic preferences (…
The Importance of Friendship in the Construction of Positive Nations
2013
This chapter is written by two Argentineans, Graciela Tonon and Lia Rodriguez de la Vega, and brings interesting data from their own studies regarding friendship as relational glue for a positive nation. Departing from the results gathered, where friendship emerged as the variable ranked with the highest value for the people interviewed, they define the concept and its typologies and connect it with the idea of a positive nation, with Martin Seligman’s flourishing model, and, finally, with Aristotle’s idea of friendship as community. Alongside the chapter, we can understand, through the testimonies and words of the interviewed, the dynamic perspectives regarding friendship as an instrument …