39,259 research outputs found
Fraction auctions: the tradeoff between effciency and running time
Get PDFThis paper studies the sales of a single indivisible object where bidders have continuous valuations. In Grigorieva et al. [13] it was shown that, in this setting, query auctions necessarily allocate inefficiently in equilibrium. In this paper we propose a new sequential auction, called the c-fraction auction. We show c-fraction auctions guarantee approximate efficiency at any desired level of accuracy, independent of the number of bidders. We discuss the running time and the efficiency in the ex-post equilibrium of the auction. We show that by changing the parameter c of the auction we can trade off efficiency against running time.operations research and management science;
On discriminating swell and wind-driven seas in voluntary observing ship data
No full text[1] The global visual wave observations are reanalyzed within the theoretical concept of self-similar wind-driven seas. The core of the analysis is one-parametric dependencies of wave height on wave period. Theoretically, wind-driven seas are governed by power-like laws with exponents close to Toba's one 3/2 while the corresponding swell exponent (À1/2) has an opposite signature. This simple criterion was used and appeared to be adequate to the problem of swell and wind-driven waves discrimination. This theoretically based discrimination does not follow exactly the Voluntary Observing Ship (VOS) data. This important issue is considered both in the context of methodology of obtaining VOS data and within the physics of wind waves. The results are detailed for global estimates and for analysis of particular areas of the Pacific Ocean. Prospects of further studies are discussed. In particular, satellite data are seen to be promising for tracking ocean swell and for studies of physical mechanisms of its evolution. Citation: Badulin, S. I., and V. G. Grigorieva (2012), On discriminating swell and wind-driven seas in Voluntary Observing Ship data
Канонический анализ категориальных данных с приложением в маркетинге
Get PDFГригорьева Ирина Владимировна. Канонический анализ категориальных данных с приложением в маркетинге. Научный руководитель: Алексеева Нина Петровна. Направление: прикладная математика и информатика, профиль: вычислительная стохастика и статистические модели.
В работе рассматривается задача исследования зависимости между двумя множествами номинальных признаков. Производится поиск связей между множествами, где в качестве меры зависимости рассматривается коэффициент неопределенности. Для расширения исходных множеств используются алгебраические методы: алгоритм быстрого перечисления точек грассманиана.
Отличие работы от других: поиск не только наибольших связей между множествами, но и самых устойчивых симптомов, в смысле уменьшения количества значимых связей и снижения уровней зависимости при их исключении из совокупностей , названных номинативными представителями.
Были получены следующие результаты: Получены искомые подмножества признаков по алгоритму быстрого перечисления точек грассманиана и наилучшие связи между получившимися подмножествами. Реализованы два метода поиска номинативного представителя: частотный способ и метод, основанный на удалении признаков. Получены номинативные представители обоих множеств при помощи методов многомерной статистики.
Количество использованных источников: 6
Григорьева, И.В. Канонический анализ категориальных данных с приложением в маркетинге: бакалаврская работа / Григорьева Ирина Владимировна. – Спб., 2016. – 60 с. – Библиогр.: с. 60.Grigorieva Irina Vladimirovna. Canonical analysis of categorical data with application in marketing. Scientific Supervisor: Alekseeva Nina Petrovna. Field of study: Applied Mathematics and Computer Science. Profile: Computational Stochastics and Statistical Models.
In work the dependence research problem between two sets of nominal attributes. Search of communications between sets where as a metrics used uncertainty coefficient. For expansion of initial sets used algebraic methods: algorithm of fast enumeration grassmanian points.
Unlike other works: search not only the greatest communications between sets, but also the steadiest symptoms.
Results: Received the desired subset by algorithm of fast enumeration grassmanian points and the best connections between subsets. Implemented two methods of search nominative representative: the frequency method and a method based on removing the attributes. Obtained nominative representatives of both sets using multivariate statistical methods.
Number of reference links: 6
Grigorieva, I. V. Canonical analysis of categorical data with application in marketing / Grigorieva Irina Vladimirovna. – SPb., 2016. – 60 p. – Bibliography.: p. 60
Problems of Translating into Russian
Get PDFThe general traditions of Russian literature has been based on the requirement that any literary translation should be good literature in itself as well as preserving the author’s manner of writing. It seems that understanding of J.R.R. Tolkien and his books is growing very slowly in Russia. There have never been any professional literary works on Tolkien or the problems of translating his works. A number of approaches to translating are connected with this fact. A short history of this subject shows that both the author’s attitude and fairy-story reality should be reproduced correctly and with care. I am going to compare Russian published versions of The Lord of the Rings (by V. Murav’ev & A. Kistyakovskii, by V. Matorina, by N. Grigorieva & V. Grushetskiy, and by Z. Bobir). The following are discussed: • The author’s and translator’s attitudes to the story they tell (horror and humour, fairies and dragons) • Reliability of Middle-earth elements - how this is achieved by different approaches (hobbits’ names and manner of speech, Elvish languages and so on) • Folklore and the nature of the hero: ways to find analogies • The laws of Faerie must not be changed! A fully adequate version should find solutions for all these problems; but really the more is done the better the translation
S. I. Gessen in Memoirs and Assessments of V. V. Zenkovsky: Page from Intellectual History of Russian Emigration
Get PDFThe relationship between S. I. Gessen and V. V. Zenkovsky, representatives of Russian philosophical, psychological, pedagogical and social thought, is considered as an episode of the intellectual history of the Russian diaspora. It is argued that the image of S. I. Gessen, formed in the scientific works and memoirs of a famous teacher, complements the idea of his personality, of the position S. I. Gessen held in the scientific, pedagogical and social life of the emigration. An analysis of the relationship between two thinkers over a quarter of a century is presented. The conclusion is drawn about the “internal dialogue” between them, which developed on the pages of emigre periodicals, was recorded in correspondence with like-minded people and became the subject of reflection and self-reflection in scientific works. The author pays special attention to assessments of the theoretical contribution of S. I. Gessen to Russian and European philosophical and pedagogical thought, which are given in reviews and surveys, the essay “Russian Pedagogy in the XX century” and “History of Russian Philosophy”. It is shown that in this context, the responses to the death of S. I. Gessen and memories of him, which make it possible to determine the attitude of V. V. Zenkovsky not only to S. I. Gessen the thinker, but also to man, acquire great importance
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
TeX v jednoduchém unixovém prostředí
Get PDFsummary:Při ladění TeXového dokumentu potřebujeme mnohokrát opakovaně pouštět TeX, podívat se, jak dopadl výsledek v prohlížeči DVI nebo PDF souboru, mrknout na výpis TeXu na terminálu, podívat se případně do logu a celou činnost opakovat. V tomto článku je ukázáno, jak tuto práci dělá autor článku. Proces "editor-TeX-kuk" je zde podporován jednoduchými unixovými nástroji: bashovým skriptem texloop, který si autor pro tyto účely vytvořil, dále terminálem Xterm a jednoduchým editorem, který umí navázat na klávesovou zkratku spuštění příkazu v systému. Čtenář se zde může inspirovat a přizpůsobit tyto nástroje svým vlastním potřebám. V článku je popsána funkce skriptu texloop, dále je neformálně rozveden dlouholetý vývoj autorova vztahu k textovým editorům a konečně je zde uvedena konfigurace terminálu Xterm, aby vyhovoval českému prostředí jak v kódování ISO-8859-2, tak v kódování UTF-8. Pro kódování UTF-8 si v závěru článku vygenerujeme TeXový formát csplain.summary:By debugging a TeX document it is necessary many times repeatedly to run TeX, to look for the result in DVI or PDF file, to gander the TeX output on the terminal, or eventually to have a look in the log-file, and all that action to repeat. In the paper it is show, how this work is made by author. The process '‘'editor-TeX-look' is supported by simple Unix tools: bash script texloop, created by author for these purposes, Xterm terminal and a simple editor, which is able to link to the shortcut key the activation of a system command. The reader could be inspired with the solution and to adapt these tools to his/her own needs. In the paper the function of the texloop script is described, and further the longstanding evolution of the author's relation to text editors is informal elaborated and finally a configuration of Xterm terminal, suitable for the czech environment with both ISO-8859-2 and UTF-8 encoding is introduced. For UTF-8 encoding the TeX format csplain is generated at the end of the paper
Neutrophil extracellular traps: a role in inflammation and dysregulated hemostasis as well as in patients with COVID-19 and severe obstetric pathology
No full textMacrophage activation syndrome in COVID-19
Get PDFThe novel coronavirus epidemic is characterized by high rates of morbidity and relatively high mortality. Laboratory test results in patients include leukopenia, an increase in liver function tests and ferritin levels reaching hundreds, and sometimes thousands of units. These data remind us about the macrophage activation syndrome (MAC). Secondary hemophagocytic lymphohistiocytosis syndrome, MAC, which pathogenesis is based on a defect in the mechanisms of T-cell cytotoxicity and decreased level of natural killer cells associated with the defect in the perforin-encoding gene as well as hyperproduction of a number of cytokines – interleukin (IL)-1â, tumor necrosis factor-á, etc. by T-lymphocytes and histiocytes, indirectly leading to the activation of macrophages and production of proinflammatory cytokines, in particular IL-6 hyperproduction. MAC is one of "hyperferritinemic syndromes". These disorders have similar clinical and laboratory manifestations, and they also respond to similar treatments, suggesting that hyperferritinemia may be involved in the overall pathogenesis and is characterized by elevated ferritin level and cytokine storm. Despite the fact that data on the immune and inflammatory status in patients with COVID-19 have only started to appear, it is already clear that hyperinflammation and coagulopathy affect the disease severity and increase the risk of death in patients infected with SARS-CoV-2. Hence, understanding the pathogenesis of the novel coronavirus infection can help in its early diagnostics and treatment
Structural and Functional Organization of the Mitochondrial DNA Control Region in the Woolly Mammoth (Mammuthus primigenius)
No full textТекст статьи не публикуется в открытом доступе в соответствии с политикой журнала.The woolly mammoth mitochondrial genome (including the Malolyakhovsky mammoth) has been previously sequenced, followed by the annotation of all its genes (MF770243). In this study, based on the Malolyakhovsky mammoth, we describe for the first time the sites of functional significance in the control region of the woolly mammoth mitogenome
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