scholarly journals A Large Set of Torus Obstructions and How They Were Discovered

10.37236/3797 ◽  
2018 ◽  
Vol 25 (1) ◽  
Author(s):  
Wendy Myrvold ◽  
Jennifer Woodcock

We outline the progress made so far on the search for the complete set of torus obstructions and also consider practical algorithms for torus embedding and their implementations. We present the set of obstructions that are known to-date and give a brief history of how these graphs were found. We also describe a nice algorithm for embedding graphs on the torus which we used to verify previous results and add to the set of torus obstructions. Although it is still exponential in the order of the graph, the algorithm presented here is relatively simple to describe and implement and fast-in-practice for small graphs.It parallels the popular quadratic planar embedding algorithm of Demoucron, Malgrange, and Pertuiset.

Muzealnictwo ◽  
2017 ◽  
Vol 58 (1) ◽  
pp. 2-13
Author(s):  
Teresa Grzybkowska

Professor Zdzisław Żygulski Jr. (1921–2015) was one of the most prominent Polish art historians of the second half of the 20th century. He treated the history of art as a broadly understood science of mankind and his artistic achievements. His name was recognised in global research on antique weapons, and among experts on Rembrandt and Leonardo da Vinci. He studied museums and Oriental art. He wrote 35 books, about 200 articles, and numerous essays on art; he wrote for the daily press about his artistic journeys through Europe, Japan and the United States. He illustrated his publications with his own photographs, and had a large set of slides. Żygulski created many exhibitions both at home and abroad presenting Polish art in which armour and oriental elements played an important role. He spent his youth in Lvov, and was expatriated to Cracow in 1945 together with his wife, the pottery artist and painter Eva Voelpel. He studied English philology and history of art at the Jagiellonian University (UJ), and was a student under Adam Bochnak and Vojeslav Molè. He was linked to the Czartoryski Museum in Cracow for his whole life; he worked there from 1949 until 2010, for the great majority of time as curator of the Arms and Armour Section. He devoted his whole life to the world of this museum, and wrote about its history and collections. Together with Prof. Zbigniew Bocheński, he set up the Association of Lovers of Old Armour and Flags, over which he presided from 1972 to 1998. He set up the Polish school of the study of militaria. He was a renowned and charismatic member of the circle of international researchers and lovers of militaria. He wrote the key texts in this field: Broń w dawnej Polsce na tle uzbrojenia Europy i Bliskiego Wschodu [Weapons in old Poland compared to armaments in Europe and the Near East], Stara broń w polskich zbiorach [Old weapons in Polish armouries], Polski mundur wojskowy [Polish military uniforms] (together with H. Wielecki). He was an outstanding researcher on Oriental art to which he dedicated several books: Sztuka turecka [Turkish art], Sztuka perska [Persian art], Sztuka mauretańska i jej echa w Polsce [Moorish art and its echoes in Poland]. Prof. Zdzisław Żygulski Jr. was a prominent educator who enjoyed great respect. He taught costume design and the history of art and interiors at the Academy of Fine Arts in Cracow, as well as Mediterranean culture at the Mediterranean Studies Department and at the Postgraduate Museum Studies at the UJ. His lectures attracted crowds of students, for whose needs he wrote a book Muzea na świecie. Wstęp do muzealnictwa [Museums in the world. Introduction to museum studies]. He also lectured at the Florence Academy of Art and at the New York University. He was active in numerous Polish scientific organisations such as PAU, PAN and SHS, and in international associations such as ICOMAM and ICOM. He represented Polish art history at general ICOM congresses many times. He was also active on diverse museum councils all over Poland.


2018 ◽  
Author(s):  
Yang Xu ◽  
Barbara Claire Malt ◽  
Mahesh Srinivasan

One way that languages are able to communicate a potentially infinite set of ideas through a finite lexicon is by compressing emerging meanings into words, such that over time, individual words come to express multiple, related senses of meaning. We propose that overarching communicative and cognitive pressures have created systematic directionality in how new metaphorical senses have developed from existing word senses over the history of English. Given a large set of pairs of semantic domains, we used computational models to test which domains have been more commonly the starting points (source domains) and which the ending points (target domains) of metaphorical mappings over the past millennium. We found that a compact set of variables, including externality, embodiment, and valence, explain directionality in the majority of about 5000 metaphorical mappings recorded over the past 1100 years. These results provide the first large-scale historical evidence that metaphorical mapping is systematic, and driven by measurable communicative and cognitive principles.


2006 ◽  
Vol 04 (01) ◽  
pp. 59-74 ◽  
Author(s):  
YING-JUN HE ◽  
TRINH N. D. HUYNH ◽  
JESPER JANSSON ◽  
WING-KIN SUNG

To construct a phylogenetic tree or phylogenetic network for describing the evolutionary history of a set of species is a well-studied problem in computational biology. One previously proposed method to infer a phylogenetic tree/network for a large set of species is by merging a collection of known smaller phylogenetic trees on overlapping sets of species so that no (or as little as possible) branching information is lost. However, little work has been done so far on inferring a phylogenetic tree/network from a specified set of trees when in addition, certain evolutionary relationships among the species are known to be highly unlikely. In this paper, we consider the problem of constructing a phylogenetic tree/network which is consistent with all of the rooted triplets in a given set [Formula: see text] and none of the rooted triplets in another given set [Formula: see text]. Although NP-hard in the general case, we provide some efficient exact and approximation algorithms for a number of biologically meaningful variants of the problem.


Author(s):  
K.L. Dhammajoti

Abhidharma had its origin in certain systematizing, analytical, and exegetical features found in the Sūtra, particularly, mātṛikā (summary list), abhidharma-kathā (discussion about the doctrine), vibhaṅga (“analytical exposition”), and upadeśa (exegetical elaboration). Buddhist philosophies may have been primarily initiated and vigorously elevated in the Abhidharma tradition. However, while the Abhidharma treatises undoubtedly exhibit highly developed scholastic and hermeneutical components, Abhidharma is essentially a soteriology. The Sarvāstivāda Ābhidhārmikas consistently claim that Abhidharma is truly “Buddha-word,” being the sine quo non for ascertaining the true intents of the sutras—it constitutes the ultimate authority for discerning the definite and explicit discourses (nītārtha-sūtra) of the Buddha. Sarvāstivāda, the “All-exist School,” was undoubtedly one of the most important Buddhist schools in the period of Abhidharma Buddhism. Since its establishment around the 2nd century bce, it exerted tremendous impact, directly or indirectly, on the subsequent development of Indian Buddhism. This school possesses a complete set of seven canonical Abhidharma texts, nearly all of which are now preserved in Chinese translation, and one, the Prajñapti-śāstra, is preserved in a complete Tibetan translation. A huge compendia, The Great Abhidharma Commentary (Abhidharma-mahāvibhāṣā), whose gradual compilation must have spanned over more than half a century and was fully completed around 150 ce, is now extant only in Chinese. This compendia, encyclopedic in scope, defines the doctrinal positions of the orthodox Sarvāstivādins based in Kaśmīra, who subsequently came to be known as the Vaibhāṣikas. The central thesis of the school is sarvāstivāda or sarvāstitā (/sarvāstitva), which claims that all “dharmas”—fundamental realities or real entities of existence—sustain their unique intrinsic natures throughout the three periods of time. That is, whether future, past, or present, a dharma’s intrinsic nature remains the same, even though its mode of existence (bhāva) varies. This thesis was vehemently challenged by the Vibhajyavādins (Distinctionists) who denied the reality of the past and future dharmas. The reverberation of this “Sarvāstivāda-versus-Vibhajyavāda” controversy can be observed to have generated decisively significant doctrinal implications throughout the history of Buddhist thoughts. The Savāstivāda school was also known as Hetuvāda, a “school which expounds on causality.” Kātyāyanīputra (c. 150 bce), often regarded as the effective “founder” of the Sarvāstivāda school, was credited with the innovation of a theory of sixfold causes, of which the coexistent or simultaneous causality was the most important legacy. For the first time in human history, he systematically articulated a form of causality in which the cause and its effect coexist simultaneously. This theory contributed importantly to Buddhist doctrinal development, particularly its epistemology. Mahāyāna Yogācāra had embraced it from their very inception, finding it indispensable for the establishment of many of their fundamental doctrines, including “store consciousness” (ālaya-vijñāna) and “cognition-only” (vijñaptimātratā).


2017 ◽  
Vol 9 (1) ◽  
pp. 66-91 ◽  
Author(s):  
Richard A. Hawkins

Purpose This paper explores the development of a luxury retail shoe brand in Belle Époque Vienna. Design/methodology/approach Footwear retailing and marketing history is a neglected area. Unfortunately, no business records have survived from Robert Schlesinger’s shoe stores. However, it has been possible to reconstruct the history of the development of the Paprika Schlesinger brand from its extensive advertising in the Viennese newspaper, the Neue Freie Presse, with the guidance of the founder’s grandson, Prof Robert A. Shaw, Emeritus Professor of Chemistry, Birkbeck, University of London, England. This case study would not have been possible without the digitization of some major collections of primary sources. In 2014, the European Union’s Europeana digitization initiative launched a new portal via the Library of Europe website which provides access to selected digitized historic newspaper collections in libraries across Europe. The project partners include the Austrian National Library which has digitized full runs of several major historic Austrian newspapers, including the Neue Freie Presse. Other project partners which have digitized historic newspapers which are relevant to this paper are the Landesbibliothek Dr Friedrich Teßmann of Italy’s Südtirol region, the National Library of France and the Berlin State Library. An associate project partner library, the Slovenian National and University Library’s Digital Library of Slovenia, has also digitized relevant historic newspapers. Furthermore, the City of Vienna has digitized a complete set of Vienna city directories as part of its Wienbibliothek Digital project. Findings This paper suggests that Robert Schlesinger created one of the first European luxury retail shoe brands. Originality/value This is the first academic study of the historical development of the advertising and marketing of a European luxury retail shoe brand.


Comunicar ◽  
2015 ◽  
Vol 22 (44) ◽  
pp. 45-53 ◽  
Author(s):  
Leonard Muellner

Evidence for annotating Homeric poetry in Ancient Greece is as old as the 5th Century BCE, when the «Iliad» and «Odyssey» were performed by professional singers/composers who also performed annotations to the poetry in answer to questions from their audiences. As the long transition from a song culture into a literate society took place in Ancient Greece from the 8th to the 2nd and 1st centuries BCE, annotations were gradually incorporated into written poetic texts. By the 10th Century CE, the quantity of written annotations in the margins of medieval manuscripts has become huge. For the first two versions of «The Ancient Hero», a HarvardX MOOC, it was not possible to implement the set of annotation tools that we requested as a vehicle for close reading and assessment. Using a partial system, we were able to create a semblance of annotations in close reading self-assessment exercises. For the anticipated third version, we expect to have a complete set of textual and video annotation tools developed for HarvardX, including semantic tagging and full sharing of annotations. Such a system, which promises to make the educational experience more effective, will also inaugurate a digital phase in the long history of Homeric annotation.Las evidencias de anotaciones en la poesía homérica de la Antigua Grecia se remontan al siglo V (a.C.), cuando ya la «Ilíada» y la «Odisea» eran representadas por cantantes profesionales/compositores, que hacían anotaciones en la poesía para responder a los interrogantes de su público. A medida que la transición, desde una cultura de la canción a una sociedad alfabetizada, aconteció en este período de la Antigua Grecia, entre el siglo VIII al I y II (a.C.), las anotaciones se incorporaron poco a poco en los escritos poéticos. La cantidad de anotaciones escritas en los márgenes de los manuscritos medievales se volvió enorme hacia el siglo X. En las dos primeras versiones de «The Ancient Hero» en el MOOC de HarvardX no fue posible utilizar el conjunto de herramientas de anotación solicitadas como medio para una atenta evaluación de las lecturas. Utilizando un sistema parcial, hemos sido capaces de crear aparentes anotaciones en los primeros ejercicios de autoevaluación de lectura. En la tercera versión, disponemos ya de un conjunto completo de herramientas de anotaciones de texto y de vídeo, desarrollados para HarvardX, incluyendo etiquetado semántico y anotaciones compartidas. Dicho sistema nos permitirá una experiencia educativa más eficaz, inaugurando también una fase digital en la larga historia de la anotación homérica.


Blood ◽  
2010 ◽  
Vol 115 (5) ◽  
pp. 975-984 ◽  
Author(s):  
Katia Basso ◽  
Masumichi Saito ◽  
Pavel Sumazin ◽  
Adam A. Margolin ◽  
Kai Wang ◽  
...  

Abstract BCL6 is a transcriptional repressor required for mature B-cell germinal center (GC) formation and implicated in lymphomagenesis. BCL6's physiologic function is only partially known because the complete set of its targets in GC B cells has not been identified. To address this issue, we used an integrated biochemical-computational-functional approach to identify BCL6 direct targets in normal GC B cells. This approach includes (1) identification of BCL6-bound promoters by genome-wide chromatin immunoprecipitation, (2) inference of transcriptional relationships by the use of a regulatory network reverse engineering approach (ARACNe), and (3) validation of physiologic relevance of the candidate targets down-regulated in GC B cells. Our approach demonstrated that a large set of promoters (> 4000) is physically bound by BCL6 but that only a fraction of them is repressed in GC B cells. This set of 1207 targets identifies several cellular functions directly controlled by BCL6 during GC development, including activation, survival, DNA-damage response, cell cycle arrest, cytokine signaling, Toll-like receptor signaling, and differentiation. These results define a broad role of BCL6 in preventing centroblasts from responding to signals leading to exit from the GC before they complete the phase of proliferative expansion and of antibody affinity maturaton.


Author(s):  
Peng-Yeng Yin ◽  
Fred Glover ◽  
Manuel Laguna ◽  
Jia-Xian Zhu

A recent study (Yin, et al., 2010) showed that combining Particle Swarm Optimization (PSO) with the strategies of Scatter Search (SS) and Path Relinking (PR) produces a Cyber Swarm Algorithm that creates a more effective form of PSO than methods that do not incorporate such mechanisms. In this chapter, the authors propose a Complementary Cyber Swarm Algorithm (C/CyberSA) that performs in the same league as the original Cyber Swarm Algorithm but adopts different sets of ideas from the Tabu Search (TS) and the SS/PR template. The C/CyberSA exploits the guidance information and restriction information produced in the history of swarm search and the manipulation of adaptive memory. Responsive strategies using long-term memory and path relinking implementations are proposed that make use of critical events encountered in the search. Experimental results with a large set of challenging test functions show that the C/CyberSA outperforms two recently proposed swarm-based methods by finding more optimal solutions while simultaneously using a smaller number of function evaluations. The C/CyberSA approach further produces improvements comparable to those obtained by the original CyberSA in relation to the Standard PSO 2007 method (Clerc, 2008). These findings motivate future investigations of Cyber Swarm methods that combine features of both the original and complementary variants and incorporate additional strategic notions from the SS/PR template as a basis for creating a still more effective form of swarm optimization.


2020 ◽  
Author(s):  
Lukáš Fasora ◽  
Jan Čermin ◽  
Jana Čerminová ◽  
Jiří Hanuš ◽  
Michaela Máliková

The book commemorating the centenary of the establishment of the Faculty of Arts is also a contribution to the anniversary of the whole Masaryk University. Its aim is to walk through the history of the faculty by means of a biographical method, i.e., using short biographies that introduce representative, prominent or interesting personalities whose fates and work were connected with the faculty. There was certainly no lack of biographical views in the research of the faculty history, still, such a complex set of biograms has not been collected so far. And the publication offers much more: the authors use a large set of biographical data to interpret the history of the faculty from the perspective of alternating academic generations and contemplate the formative generation experience as well as the phenomena that affected the lives of academics and students over the past 100 years. These include, as a matter of fact, both positive and negative phenomena, therefore, the publication is not just an overview of deserving personalities, respected scientists and charismatic teachers, but it also openly discusses the lives of controversial scholars. Thus, the collection of biograms provides a credible testimony to the one-hundred-year work of the faculty, continually blending studies, science and politics.


2018 ◽  
Vol 35 (1) ◽  
pp. 193-228
Author(s):  
Nebahat Avcıoğlu

Abstract This article is a study of the family photo album of Elisabeth Leitner (ca. 1842?–1908), a Hungarian immigrant in the Ottoman empire. The album contains a complete set of cartes de visite portraits of the Ottoman sultans by the Abdullah Frères. As the only surviving example of such a collection with a known provenance, it provides a rare opportunity for understanding how such images were used in the context of identity formation and social mobility undertaken by a member of the immigrant population. The album, which has never been studied before, is also a fascinating source for investigating the history of Hungarian immigrants in the Ottoman empire who were displaced after the 1848 Revolution. The article approaches the intriguingly autobiographical album by means of a close reading of Elisabeth Leitner’s diaries and unfinished autobiography. My interpretation serves to dismantle notions of a carefree global cosmopolitanism and exposes a historiographical bias that privileges men and their collections of images and ethnographic artifacts over those of women. Elisabeth Leitner’s writings and photographic collection also represent a vast and entirely untapped resource for investigating cultural contacts between Europe and the Ottoman empire in the second half of the nineteenth century.


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