College admissions with stable score-limits

A common feature of the Hungarian, Irish, Spanish and Turkish higher education admission systems is that the students apply for programmes and they are ranked according to their scores. Students who apply for a programme with the same score are in a tie. Ties are broken by lottery in Ireland, by objective factors in Turkey (such as date of birth) and other precisely defined rules in Spain. In Hungary, however, an equal treatment policy is used, students applying for a programme with the same score are all accepted or rejected together. In such a situation there is only one question to decide, whether or not to admit the last group of applicants with the same score who are at the boundary of the quota. Both concepts can be described in terms of stable score-limits. The strict rejection of the last group with whom a quota would be violated corresponds to the concept of H-stable (i.e. higher-stable) score-limits that is currently used in Hungary. We call the other solutions based on the less strict admission policy as L-stable (i.e. lower-stable) score-limits. We show that the natural extensions of the Gale-Shapley algorithms produce stable score-limits, moreover, the applicant-oriented versions result in the lowest score-limits (thus optimal for students) and the college-oriented versions result in the highest score-limits with regard to each concept. When comparing the applicant-optimal H-stable and L-stable score-limits we prove that the former limits are always higher for every college. Furthermore, these two solutions provide upper and lower bounds for any solution arising from a tie-breaking strategy. Finally we show that both the H-stable and the L-stable applicant-proposing scorelimit algorithms are manipulable

Editorial: special issue on matching under preferences

This special issue of Algorithms is devoted to the study of matching problems involving ordinal preferences from the standpoint of algorithms and complexit

Grain boundaries in graphene grown by chemical vapor deposition

The scientific literature on grain boundaries (GBs) in graphene was reviewed. The review focuses mainly on the experimental findings on graphene grown by chemical vapor deposition (CVD) under a very wide range of experimental conditions (temperature, pressure hydrogen/hydrocarbon ratio, gas flow velocity and substrates). Differences were found in the GBs depending on the origin of graphene: in micro-mechanically cleaved graphene (produced using graphite originating from high-temperature, high-pressure synthesis), rows of non-hexagonal rings separating two perfect graphene crystallites are found more frequently, while in graphene produced by CVD—despite the very wide range of growth conditions used in different laboratories—GBs with more pronounced disorder are more frequent. In connection with the observed disorder, the stability of two-dimensional amorphous carbon is discussed and the growth conditions that may impact on the structure of the GBs are reviewed. The most frequently used methods for the atomic scale characterization of the GB structures, their possibilities and limitations and the alterations of the GBs in CVD graphene during the investigation (e.g. under e-beam irradiation) are discussed. The effects of GB disorder on electric and thermal transport are reviewed and the relatively scarce data available on the chemical properties of the GBs are summarized. GBs are complex enough nanoobjects so that it may be unlikely that two experimentally produced GBs of several microns in length could be completely identical in all of their atomic scale details. Despite this, certain generalized conclusions may be formulated, which may be helpful for experimentalists in interpreting the results and in planning new experiments, leading to a more systematic picture of GBs in CVD graphene

Remembering and Forgetting: Lizkor VeLishkoach for String Quartet, after Schubert

Lizkor VeLishkoach (to Remember and to Forget) is a piece that is to be played together with Franz Schubert’s Quartet in G Major D887. Lizkor VeLishkoach (hebrew for “to remember and to forget”) forms its meaning from the roots of the words of its title. The root of “lizkor” is “zekher”, which means both “memory” and “imprint.” Embedded within the verb “lishkoakh” is the word “koakh” meaning “power.” In this paper, I explore aspects of time, memory and place within my quartet, aspects that have become “imprinted” within a personal subjective and larger collective memory. Investigating my own reaction to Schubert’s quartet, I examine how its form and material is re-collected within my own composition. Retracing the re-membering of Schubert’s quartet, I also speculate about my own re-membering and forgetting within the context of this chosen form.Lizkor VeLishkoach est une pièce qui est conçue pour être au même programme que le Quatuor en sol majeur D887 de Franz Schubert. Lizkor VeLishkoach (qui signifie « Se souvenir et oublier » en hébreu) trouve tout son sens dans la racine des mots qui forment son titre. La racine de « lizkor » est « zekher », qui singnifie à la fois « mémoire » et « impression ». Le verbe « lishkoakh » contient le mot « koakh », qui singifie « pouvoir ». Dans cet article, l’auteur explore des aspects du temps, de la mémoire et du lieu auquels se rattache son quatuor, des aspects qui sont « imprimés » dans sa propre mémoire subjective, mais aussi dans une plus vaste mémoire collective. Analysant sa propre perception du quatuor de Schubert, il vérifie à quel point sa forme et son matériau sont réappropriés dans son oeuvre à lui. Retraçant les rappels au quatuor de Schubert, il spécule sur ses propres souvenirs et oublis dans le contexte de la forme choisie

The Practice of Teaching Composition

In this essay, composer Dániel Péter Biró reveals his methodology and trajectory as a professor of music composition in the last 16 years. Biró explains how can one teaches a creative artistic process nowadays, in a globalized musical culture, which is full of possibilities for development of cultural diversity while simultaneously providing students distractions driven by capitalist paradigms. How can one help each student to develop his/her own musical language? For this task, Biró talks about how composition today is creative process highly grounded in intellectual and interdisciplinary approaches, sharing similarities with other areas of research such as philosophy and history. For this task, the composer relies on musical analysis in his seminars and individual lessons as one of the strongest methodologies to learn composition, alongside integrating music technology and contemporary performance practice research. [note by editor]

Historicized Composition and Creative Ethnomusicology

This paper investigates relationship between compositional and ethnomusicological research. The method of historicized composition developed out of my work as a chant scholar, as ongoing ethnomusicological research has had a profound influence on my compositional work. Understanding and underscoring historical and phenomenological relationships between music and language, the act of composition becomes a creative discovery of relationships between musical material and music history