1,203 research outputs found

    Thermal correlators of anyons in two dimensions

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    The anyon fields have trivial α\alpha-commutator for α\alpha not integer. For integer α\alpha the commutators become temperature-dependent operator valued distributions. The nn-point functions do not factorize as for quasifree states.Comment: 14 pages, LaTeX (misprints corrected, a reference added

    A Framework for Design-Time Testing of Service-Based Applications at BPEL Level

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    Software applications created on top of the service-oriented architecture (SOA) are increasingly popular but testing them remains a challenge. In this paper a framework named TASSA for testing the functional and non-functional behaviour of service-based applications is presented. The paper focuses on the concept of design time testing, the corresponding testing approach and architectural integration of the consisting TASSA tools. The individual TASSA tools with sample validation scenarios were already presented with a general view of their relation. This paper’s contribution is the structured testing approach, based on the integral use of the tools and their architectural integration. The framework is based on SOA principles and is composable depending on user requirements.The work reported in this paper was supported by a research project funded by the National Scientific Fund, Bulgarian Ministry of Education, Youth and Science, via agreement no. DOO2-182

    Þráðormasamfélög Surtseyjar 50 árum eftir myndun hennar.

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    Soil nematodes are a key group that can both influence and reflect changes in the soil ecosystem. We investigated the generic composition, abundance and community structure of soil nematodes in two contrasting vegetation successional seres now found on the 50 year old volcanic island of Surtsey, Iceland. One represented the primary succession without much external input of nutrients (S1), while the other was a grassland that has evolved under a strong influence of allochthonous nutrient inputs by gulls (S2). In 2012 in total 25 genera of nematodes were identified, of which 14 were reported on Surtsey for the first time. Across the whole island, the nematode abundance and distribution was most strongly related to soil C:N ratio, soil acidity, plant cover and biomass. The nematode abundance was higher at S2 and there the trophic structure was dominated by bacterial- and plantfeeders, while hyphal-feeders were more dominant at S1. Nematode communities have continued to change at S1 since the last nematode survey, which took place 17 years ago, even where the vegetation cover and composition has remained stable. This may indicate a gradual change in the soil environment at S1. Within S2, the nematode community had become denser and more structured, but still it had lower generic diversity than found at S1. Resource availability was found to be an important driver for nematode colonization and primary succession on this isolated volcanic island. However, the study also found that soil nematode communities may show a different pattern of succession than plant communities.Samfélög þráðorma í jarðvegi gegna mikilvægu hlutverki í frumframvindu og jarðvegsmyndun. Í þessari grein var fjallað um þær breytingar sem hafa orðið á samfélögum þráðorma í jarðvegi á Surtsey síðan að hún myndaðist 1963. Megin áherslan var lögð á að bera saman fjölda ættkvísla, þéttleika og skiptingu þeirra í fæðuhópa á milli tveggja megin framvindustiga gróðurs á Sutsey; á svæðum með lítilli næringarefnaákomu (S1) og svæðum innan þétts máfavarps á eynni þar sem næringarefnaákoma er mikil og gróðurframvinda er lengra komin (S2). Alls fundust 25 ættkvíslir þráðorma í þessari rannsókn og 14 þeirra höfðu ekki fundist áður á Surtsey. Þegar öll gögnin voru skoðuð saman kom í ljós að bæði þéttleiki og samsetning þráðormasamfélaga sýndi sterkast samband við C:N hlutfall í jarðvegi, sýrustig jarðvegs, gróðurþekju og ofanjarðarlífmassa gróðurs. Þéttleiki þráðorma var hærri á S2 og bakteríu- og plönturótaætur einkenndu samfélögin þar á meðan sveppþráðaætur einkenndu samfélögin á S1. Þráðormasamfélögin á S1 höfðu breyst frá síðustu úttekt þar fyrir 17 árum, þrátt fyrir að gróðurþekja og samsetning gróðurs hafi ekki breyst þar. Þetta bendir til breytinga (framvindu) á jarðvegsþáttum sem ekki sér merki ofanjarðar. Á S2 höfðu þráðormasamfélögin á sama tíma orðið þéttari og 44 ICELANDIC AGRICULTURAL SCIENCES með flóknari fæðuvef, en fjölbreytileiki þeirra var samt minni en á S1. Næringarefnaákoma, gróðurframvinda og jarðvegsmyndun voru afgerandi þættir í frumframvindu þráðorma. Athygli vakti einnig að framvinda þráðorma hafði að hluta til annan feril en gróðurframvinda á SurtseyPeer ReviewedRitrýnt tímari

    Anyons and the Bose-Fermi duality in the finite-temperature Thirring model

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    Solutions to the Thirring model are constructed in the framework of algebraic QFT. It is shown that for all positive temperatures there are fermionic solutions only if the coupling constant is λ=2(2n+1)π,nN\lambda=\sqrt{2(2n+1)\pi}, n\in {\bf N}. These fermions are inequivalent and only for n=1n=1 they are canonical fields. In the general case solutions are anyons. Different anyons (which are uncountably many) live in orthogonal spaces and obey dynamical equations (of the type of Heisenberg's "Urgleichung") characterized by the corresponding values of the statistic parameter. Thus statistic parameter turns out to be related to the coupling constant λ\lambda and the whole Hilbert space becomes non-separable with a different "Urgleichung" satisfied in each of its sectors. This feature certainly cannot be seen by any power expansion in λ\lambda. Moreover, since the latter is tied to the statistic parameter, it is clear that such an expansion is doomed to failure and will never reveal the true structure of the theory. The correlation functions in the temperature state for the canonical dressed fermions are shown by us to coincide with the ones for bare fields, that is in agreement with the uniqueness of the τ\tau-KMS state over the CAR algebra (τ\tau being the shift automorphism). Also the α\alpha-anyon two-point function is evaluated and for scalar field it reproduces the result that is known from the literature.Comment: 25 pages, LaTe

    INNs granted with specific storage requirements in Bulgarian pharmacies. Part 2: Antineoplastic and immunomodulating agents

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    There are drugs that require special storage in Bulgarian pharmacies as well as extra caution during the dispensing process. This is due to serious adverse reactions that may be even fatal. These medicines are included in Appendix № 9 to Art. 17, para. 1 of Ordinance № 28/9.12.2008, issued by the Minister of Health. The performed study of the anticancer drugs listed in the Appendix showed that a major part of these medicines that have a marketing authorization for use in Bulgaria are not included in the Appendix № 9. In addition, there are antitumor drugs that are listed in the appendix but are not authorized in Bulgaria to date. In conclusion, it is necessary to periodically update the drugs in Appendix № 9 as well as to develop clear and precise criteria for the inclusion of medicines in it

    IMPACT OF COVID-19 ON PHYSICAL ACTIVITY OF HIGH SCHOOL STUDENTS (BULGARIAN EXPERIENCE)

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    The neglect of physical activity in the education of high-school students (14 – 19 years old) during the COVID-19 pandemic could lead to serious consequences for their physical development and put their health at risk. In order to mitigate the problem with inactivity many countries all over the world use different approaches to sports classes. In cases where attendance is not possible, it is necessary to provide distance learning with maximum efficiency. The aim of the study was to examine the opinion of high-school students on the influence of COVID-19 on their physical activity and to optimize the learning process in physical education and sports under the conditions of distance learning in an electronic environment (DLEE). The study was carried out with 43 respondents who met the criteria of the target group. The survey was administered in two phases. Two questionnaires were completed by the participating students. The analysis of the results shows that in Bulgaria the pandemic does not have a negative influence on the physical activity of high-school students. We assume that the main reasons for this observation are the more liberal measures and the availability of options to use different sports facilities. In perspective, it would be useful to identify contemporary and innovative methods for improvement and monitoring of the activity of high-school students under the conditions of DLEE

    Verteilte Bearbeitung von Zeichnungen im Bauwesen

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    Eine Bauunterlage ist in der Regel an mehreren Orten vorhanden. Sie wird von verschiedenen Personen an verschiedenen Orten zu verschiedenen Zeitpunkten geändert. Die Änderungen sind häufig und in vielen Fällen von geringem Umfang. Die Verteilung solcher Unterlagen in Computernetzen, sowie die Durchführung und die Verwaltung von Änderungen stellen hohe Anforderungen an die Informations- und Kommunikationstechnik. Insbesondere ist die Konsistenz der Unterlagen unter Berücksichtigung der typischen Merkmale des Arbeitsablaufes im Bauwesen zu sichern. Im Vortrag wird ein Konzept für die Bearbeitung von Bauunterlagen, insbesondere für Zeichnungen, in Computernetzen vorgestellt. Grundlage dieses Konzeptes ist die Norm ISO 10303 STEP (The standard for exchange of product model data). Das AP 201 >Explicit draughting< der ISO 10303 wurde als Austauschformat für Zeichnungen festgelegt. Im Rahmen des Vortrages wird ein Projektmodell vorgestellt. Das Projektmodell bildet den Informationsfluß während des Bauprozesses ab und ermöglicht die Sicherung der Konsistenz einer Zeichnung während der Bearbeitung der verschiedenen Fachleute. Bei Änderung einer Zeichnung wird ausschließlich die Differenzmenge als Information übertragen. Da die Arbeitsweise des Ingenieurs im Bauwesen eine Vollauthomatisierung des Datenaustausches nicht zuläßt, werden Änderungen nur nach Entscheidung des zuständigen Fachmanns in die ursprüngliche Fassung der Zeichnung übernommen. Werkzeuge für die Unterstützung der Auflösung von Widersprüchen in einem Dokument werden vorgestellt

    In situ FT-IR investigation of the reduction of NO with CO over Au/CeO2-Al2O3 catalyst in the presence and absence of H-2

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    Cataloged from PDF version of article.he NO + CO + H-2 reaction over CeO2, Au/CeO2 (3 wt% Au), Au/CeO2-Al2O3 (2.9 wt% Au, 20 wt% Al2O3) and CeO2-Al2O3 mixed support prepared by co-precipitation has been Studied by FT-IR spectroscopy at elevated temperatures. Formation of NCO species has been detected on all of the samples. The presence of metallic gold is not necessary for the generation of the isocyanates on ceria and the mixed ceria-alumina support. The NCO species are produced by a process involving the dissociation of NO on the oxygen vacancies of the support, followed by the reaction between N atoms lying oil the surface and CO molecules. Gold plays an important role in the modification of ceria leading to Ce3+ and oxygen vacancies formation, and causes significant lowering of the reduction temperature of CeO2 and CeO2-Al2O3 enhancing the reducibility of ceria surface layers. The role of H-2 is to keep the surface reduced during the course of the reaction. The onset temperature, at which the interaction between the surface isocyanates and No begins, is low (100 degrees C). This explains the high activity of the Au/CeO2-Al2O3 catalyst with 100% selectivity in the reduction of NO by CO at low temperature (200 degrees C) and in the presence of H-2 (C) 2008 Elsevier B.V. All rights reserve

    Roof Segmentation Towards Digital Twin Generation in LoD2+Using Deep Learning

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    There is an increasing need for digital twins of cities and their base maps, 3D city models. Creating and updating these twins is not an easy task, so automating and streamlining the process is a field of active research. A significant part of the urban geometry is residential buildings and their roofs. Modeling of roofs for urban buildings can be divided into three main areas - building detection, roof recognition and building reconstruction. The building and roofs are segmented with the help of machine learning and image processing. Afterwards the extracted information is used to generate parametric models for the roofs using methods from computational geometry. The goal is to create correct virtual models of roofs belonging to many different types of buildings. In this study, a supervised deep learning approach is proposed for the segmentation of roof edges from a single orthophoto. The predicted features include the linear elements of roofs. The experiments show that, despite the small amount of training data, even in the presence of noise, the proposed method performs well on semantic segmentation of roofs with different shapes and complexities. The quality of the extracted roof elements for the test area is about 56% and 71% for mean intersection over union (IOU) and Dice metric scores, respectively. Copyright (C) 2022 The Authors
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