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The use of foundry sand in the composition of the asphalt mixture
Get PDFGlavne sestavine proizvedenih asfaltnih zmesi predstavljajo različne frakcije kamenih materialov, kamene moke ter bitumna. V proizvedeni toni asfaltne zmesi predstavlja približno 85% masnega deleža kameni material. Pri uporabi sekundarnih surovin, kot nadomestilu kamenih materialov za proizvodnjo asfaltnih zmesi, se lahko izognemo problemom povezanih s pridobivanjem ustreznih kamenih frakcij oziroma jih bistveno zmanjšamo. V magistrskem delu je prikazana možnost uporabe livarskega peska, kot sekundarne surovine ali nadomestek frakcij kamenega materiala pri proizvodnji asfaltnih zmesi.
Cilj magistrskega dela je preveriti ali z odpadnim livarskim peskom lahko enakovredno nadomestimo kamene frakcije v asfaltni zmesi, oziroma če lahko pride celo do določenega izboljšanja v smislu zmanjšanja porabljene energije pri proizvodnji vročih asfaltnih zmesi, kot tudi pri vgrajevanju. Pri tem pa ne sme priti do poslabšanja bistvenih lastnosti asfaltnih zmesi, kot so na primer: odpornost proti nastanku kolesnic, odpornost na vodo in odpornost na nizke temperature. Zaradi bentonitov vsebovanih v izbranih livarskih peskih je pričakovano lažje zgoščanje asfaltnih zmesi, oziroma možnost zgoščanja asfaltnih zmesi pri nižjih temperaturah od običajnih. Podoben vpliv na zgoščevanje zaradi kristalno vezane vode imajo tudi zeoliti.
Glavni del preiskav magistrskega dela je namenjen ovrednotenju prispevka livarskega peska k lažjem zgoščevanju asfaltnih zmesi. Iz tega izhajam, da pri dodajanju livarskega peska v asfaltne zmesi, ne gre le za dodajanje večje količine sekundarne surovine, temveč tudi za dodaten efekt zgoščevanja pri nižji temperaturi zaradi vsebnosti bentonita, ki je zaradi vezane vode še aktiven. Pri tem pa morajo biti izvedene vse preiskave bistvenih lastnosti asfaltnih zmesi z dodanim livarskim peskom, za preveritev, če dodani livarski pesek vpliva na te lastnosti asfaltnih zmesi.
Z raziskavami smo v magistrski nalogi ugotovili, da dodani livarski pesek bistveno vpliva le na lažjo vgradljivost asfaltnih plasti. Že 4 % dodanega livarskega peska ima na zgoščanje podoben vpliv, kot najpogosteje uporabljeni nizkotemperaturni dodatki (parafinski voski in zeolit). Iz rezultatov pa je razvidno, da so nekatere mehanske lastnosti (stabilnost in togost) nekoliko slabše v asfaltni zmesi pripravljeni pri 120 °C v primerjavi z mehanskimi lastnostmi asfaltne zmesi pripravljene pri 150 °C, vendar bi po kriterijih standarda JUS U.E4.014 še zmeraj ustrezale zahtevam. Poudariti velja, da standard JUS od leta 2003 ni več v veljavi, kriteriji za stabilnost in deformacijo pa niso več zahtevani. Za asfaltne zmesi uporabljene na letališčih pa določa standard SIST EN 13108-1 samo kategorije, zahtevane kategorije za konkretne asfalte pa izbere naročnik. Čeprav mehanski lastnosti, to sta stabilnost in deformacija oziroma njuni mejni vrednosti nista več zahtevani in določeni s standardom pri laboratorijskem preskušanju asfaltnih zmesi za gradnjo cest, smo jih uporabili kot izhodišče za določitev in opredelitev sprememb parametrov dveh osnovnih mehanskih lastnosti – stabilnosti in deformacije. Tako je mogoče enostavneje definirati ali so se mehanske lastnosti spreminjale bistveno z dodajanjem livarskega peska asfaltni zmesi pri različnih temperaturah. Znižanje temperature torej bolj vpliva na stabilnost asfaltnih preskušancev, količina dodanega livarskega peska pa na indirektno natezno trdnost ITSR.
Torej lahko v asfaltno zmes dodamo do 9 % livarskega peska brez bistvenega poslabšanja kakovosti asfaltne plasti.The main components of asphalt mixtures are fractions of stone aggregates, filler and bitumen. The main component in produced asphalt mixture by mass represents stone fractions with about 85% by weight. When stone materials for the production of asphalt mixtures are replaced with secondary raw materials, then problems associated with acquiring suitable stone fractions can be avoided or at least significantly reduced. The study presents the possibility of use of foundry sand as a secondary raw material that is a substitute fraction of stone material in the production of asphalt mixtures.
The aim of the master thesis is to examine whether the waste moulding sand can be used as substitute for mineral fractions in asphalt mixtures. Additionally it was assumed that there can be even some improvement in terms of reducing the consumed energy for the production and building in of hot mix asphalt mixture. At the same time there must be ne decrease in the essential characteristics of the bituminous mixture, such as, for example, resistance to the resistance to rutting, water resistance and resistance to low temperatures. Because bentonites contained in the selected foundry sands is was expected easier compaction of the asphalt layers, or the possibility of compaction of asphalt layers at lower temperatures than normal. Similar effects to ease of compaction due to crystal bound water are known for zeolites.
The main part of the master work is designed to evaluate the contribution of foundry sand to compaction of asphalt mixtures. The goal of addition of foundry sand in asphalt mixtures, is not just adding large quantities of secondary raw materials, but also to prove additional positive effect on compaction at lower temperatures due to the presence of bentonite in which is still some active bound water. All significant tests of the intrinsic properties of asphalt mixtures were carried out to verify if addition of the foundry sand effect on these properties of asphalt mixtures.
It was found out that the addition of foundry sand substantially affect only on the ease of workability of asphalt layers. Only addition of 4% foundry sand has similar effect as the most commonly used low-temperature additives (paraffin waxes and zeolite). From the results it is evident decrease in some mechanical properties (stability and Marshall stiffness) for asphalt mixtures prepared at 120 °C in comparison with the mechanical properties of the asphalt mixtures prepared at 150 °C. But, according to the criteria of the standard JUS U.E4.014 all asphalt mixtures still meet the requirements. It should be noted that the standard JUS since 2003 is no longer in force and so criteria for the stability and deformation are no longer officially required for roads. In the standard EN 13108-1 are only categories or asphalt mixtures used in airports, required categories for concrete asphalt are determined by contracting authority. Although the mechanical properties of stability and deformation or their limit values are no longer required and determined by the standard for laboratory testing of asphalt mixtures for road construction, they were used to identify and define the change in two basic mechanical properties - stability and deformation. In this way it was possible to easily define if mechanical properties of asphalt mixture changed significantly with the addition of foundry sand at different temperatures. Decrease in production temperature and thus more impact on the stability of asphalt test, on the other hand the amount of added foundry sand effect on the indirect tensile strength ITSR.
So in the asphalt mixture can be added to the 9 % foundry sand, with no substantial effect on the quality of the asphalt layer
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
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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