13,854 research outputs found
Topological String, Supersymmetric Gauge Theory and BPS Counting
No full textIn this thesis we study the Donaldson-Thomas theory on the local curve geometry, which arises in the context of geometric engineering of supersymmetric gauge theory from type IIA string compactification. The topological A-model amplitude gives the F-term interaction of the com-pactified theory. In particular, it is related to the instanton partition function via Nekrasov conjecture. We will introduce ADHM sheaves on curve, as an alternative description of local Donaldson-Thomas theory. We derive the wallcrossing of ADHM invariants and their refinements. We show that it is equivalent to the semi-primitive wallcrossing from supergravity, and the Kontsevich-Soibelman wallcrossing formula. As an application, we discuss the connection between ADHM moduli space with Hitchin system. In particular we give a recursive formula for the Poincare polynomial of Hitchin system in terms of instanton partition function, from refined wallcrossing. We also introduce higher rank generalization of Donaldson-Thomas invariant in the context of ADHM sheaves. We study their wallcrossing and discuss their physical interpretation via string duality
Hydrodynamic benefit of cephalic fins in a self-propelled flexible manta ray
No full textThe hydrodynamic benefit of cephalic fins in manta ray was explored using the penalty immersed boundary method. When manta rays feed, they open their cephalic fins and lower them to their mouth. As they swim forward, the cephalic fins are straightened in the forward direction. The smooth body of manta rays was modeled as a flexible plate. A self-propelled flexible plate was realized by enforcing a prescribed harmonic oscillation in the vertical direction but allowing the plate to move freely in the horizontal direction. Simulations without cephalic fins were also performed for comparison. Vortical structures and pressure distributions were visualized to elucidate the hydrodynamic benefits of cephalic fins. The fins generated streamwise vortices that resulted in negative pressure and enhanced the average cruising speed and thrust. The effect of the gap distance (g/L, where g is the gap distance between the two cephalic fins and L is the length of the plate) was examined in detail. The underlying propulsion mechanism was analyzed by examining the phase of the heaving stroke. The effects of the g/L were scrutinized by visualizing the contours of vorticity (omega(x), omega(y), omega(z)) and pressure (p) around the flexible plate. A maximum cruising speed was obtained at g/L = 0.6, where the average cruising speed increased by more than 62.8%.
Overview of the Author Profiling Task at PAN 2013
No full text[EN] This overview presents the framework and results for the Author Profiling
task at PAN 2013. We describe in detail the corpus and its characteristics,
and the evaluation framework we used to measure the participants performance to
solve the problem of identifying age and gender from anonymous texts. Finally,
the approaches of the 21 participants and their results are described.The author profiling task @PAN-2013 was an activity of the WIQ-EI IRSES project (Grant No. 269180) within the FP 7 Marie Curie People Framework of the European Commission. We want to thank the Forensic Lab of the Universitat Pompeu Fabra Barcelona for sponsoring the award for the winner team. The work of the first author was partially funded by Autoritas Consulting SA and by Ministerio de Economía y Competitividad de España under grant ECOPORTUNITY IPT-2012-1220-430000. The work of the second author was in the framework the DIANA-APPLICATIONS-Finding Hidden Knowledge in Texts: Applications (TIN2012-38603-C02-01) project, and the VLC/CAMPUS Microcluster on Multimodal Interaction in Intelligent Systems. The work of fifth author was funded in part by the Swiss National Science Foundation (SNF) project "Mining Conversational Content for Topic Modelling and Author Identification (ChatMiner)" under grant number 200021_130208.Rangel, F.; Rosso, P.; Koppel, M.; Stamatatos, E.; Inches, G. (2013). Overview of the Author Profiling Task at PAN 2013. CLEF Conference on Multilingual and Multimodal Information Access Evaluation. 352-365. https://riunet.upv.es/handle/10251/46636S35236
Yin zhi wen ling yan ji
No full text[潘成雲原序].綫裝, 1函.框19.7x13.2公分, 9行25字, 小字雙行同. 白口, 左右雙邊, 單黑魚尾. 版心上鐫題名, 中鐫小題, 下鐫葉次. 行間有圈點.題名據版心.內封背頁鐫"光緖己亥仲春開雕", 並印有"千歲坊文光齋印板存甯城報德觀"前附《文昌帝君陰騭文》(周振翰錄), 《陰騭文原始》, 《陰騭文靈驗記》 ; 卷末附捐刊姓氏芳名.Xian zhuang, 1 han.Kuang 19.7 x 13.2 gong fen, 9 hang 25 zi, xiao zi shuang hang tong. Bai kou, zuo you shuang bian, dan hei yu wei. Ban xin shang juan ti ming, zhong juan xiao ti, xia juan ye ci. Hang jian you quan dian.Ti ming ju ban xin.Nei feng bei ye juan "Guangxu ji hai zhong chun kai diao", bing yin you "Qian sui fang Wen guang zhai yin ban cun Ning Cheng Bao de guan"Qian fu "Wenchang di jun yin zhi wen" (Zhou Zhenhan lu), "Yin zhi wen yuan shi", "Yin zhi wen ling yan ji" ; juan mo fu juan kan xing shi fang ming.[Pan Chengyun yuan xu]
Uncovering Plagiarism - Author Profiling at PAN
No full text[ES] PAN is a yearly workshop and evaluation lab on uncovering plagiarism, authorship, and social software misuse. Since 2009, PAN has been organizing benchmark activities on uncovering plagiarism, authorship, and social software misuse . An additional task - author profiling - has also recently been proposed. Author profiling, instead of focusing on individual authors, studies how language is shared by a class of people. Author profiling is a problem of growing importance in applications in forensics, security and marketing. For instance, a person working in the area of forensic linguistics may need to know the linguistic profile of a suspected text message (language used by a certain type of person) and identify characteristics (with language as evidence). Similarly, from a marketing viewpoint, companies may be interested in determining, through the analysis of blogs and online product reviews, what types of people like or dislike their products.Rosso, P.; Rangel Pardo, FM. (2014). Uncovering Plagiarism - Author Profiling at PAN. Ercim News. (96):49-49. https://riunet.upv.es/handle/10251/49303S49499
Overview of PAN 2018 : author identification, author profiling, and author obfuscation
No full textAbstract: PAN 2018 explores several authorship analysis tasks enabling a systematic comparison of competitive approaches and advancing research in digital text forensics. More specifically, this edition of PAN introduces a shared task in cross-domain authorship attribution, where texts of known and unknown authorship belong to distinct domains, and another task in style change detection that distinguishes between single-author and multi-author texts. In addition, a shared task in multimodal author profiling examines, for the first time, a combination of information from both texts and images posted by social media users to estimate their gender. Finally, the author obfuscation task studies how a text by a certain author can be paraphrased so that existing author identification tools are confused and cannot recognize the similarity with other texts of the same author. New corpora have been built to support these shared tasks. A relatively large number of software submissions (41 in total) was received and evaluated. Best paradigms are highlighted while baselines indicate the pros and cons of submitted approaches
E.: Overview of the Author Identification Task at PAN-2013
No full textAbstract. The author identification task at PAN-2014 focuses on author verification. Similar to PAN-2013 we are given a set of documents by the same author along with exactly one document of questioned authorship, and the task is to determine whether the known and the questioned documents are by the same author or not. In comparison to PAN-2013, a significantly larger corpus was built comprising hundreds of documents in four natural languages (Dutch, English, Greek, and Spanish) and four genres (essays, reviews, novels, opinion articles). In addition, more suitable performance measures are used focusing on the accuracy and the confidence of the predictions as well as the ability of the submitted methods to leave some problems unanswered in case there is great uncertainty. To this end, we adopt the c@1 measure, originally proposed for the question answering task. We received 13 software submissions that were evaluated in the TIRA framework. Analytical evaluation results are presented where one language-independent approach serves as a challenging baseline. Moreover, we continue the successful practice of the PAN labs to examine meta-models based on the combination of all submitted systems. Last but not least, we provide statistical significance tests to demonstrate the important differences between the submitted approaches.
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