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Fire properties of natural insulation
No full textPri izbiri ustrezne toplotne izolacije objekta je treba poleg prenosa toplote, ekonomskega vidika, trdnosti in stabilnosti upoštevati tudi njihovo optimalno delovanje in čim manjši vpliv na okolje. Na tržišču obstaja več različnih vrst toplotnih izolacij, od najpogosteje uporabljene steklene volne, kamene volne, EPS in XPS do naravnih materialov, kot so volna, konoplja, celuloza, lan itd., ki imajo različne tehnične lastnosti, kot so toplotna in zvočna izolacija, požarne lastnosti, sposobnost uravnavanja vlažnosti okolja ter ogljični odtis.
V magistrskem delu so obravnavane tri naravne izolacije, ovčja volna, celulozna izolacija (lesna volna) ter izolacija iz konoplje, katerih prednost je relativno majhen vpliv na okolje, prispevek k večjemu udobju v zaprtih prostorih zaradi zmanjšanja onesnaženosti zraka in dobra požarna odpornost, že zaradi samih lastnosti materiala ali pa zaradi dodanih zaviralcev gorenja. Proksimativno analizo omenjenih vzorcev se je določilo z uporabo metod TA, in sicer EGA, TGA, DTA, DTG. S pomočjo metod TA se je ugotavljala termična stabilnost treh vzorcev toplotnih izolacij, glede na spremembo mase vzorca in toplotne spremembe v vzorcu med termično obremenitvijo vzorca. Z EGA metodo, ki združuje termogravimetrični analizator (TGA) in kvadrupolni masni spektrometer (QMS) se je poskušalo določiti oz. ugotoviti sestavo hlapnih komponent vzorcev. Cilj raziskave je ugotoviti, katera od obravnavanih naravnih izolacij je glede na proksimativno sestavo, termično stabilnost in ceno najboljša izbira, pri čemer se bo upošteval tudi ogljični odtis (GWP) in vgrajena energija (EE) vsakega vzorca izolacije.
Rezultati metod termične analize so pokazali, da ovčja volna, lesna volna in konopljina izolacija razpadejo v tristopenjskem procesu. Prva stopnja vključuje izgubo vlage, druga stopnja nastanek hlapnih komponent oz. piroliznih plinov, tretja stopnja podžig fiksnega ogljika, ostanek po termični obdelavi je pepel. Prvi dve spremembi mase vzorca potekata v inertni atmosferi (argon), tretja pa v oksidativni atmosferi (argon in kisik) v temperaturnem intervalu od 40 °C do 900 °C, pri čemer so se beležile nastale komponente termičnega razpada vzorca.
Ugotovitve so pokazale, da je konopljina izolacija imela večjo termično obstojnost zaradi višje temperature nastanka piroliznih plinov in najmanjši (negativni) ogljični odtis (GWP). Volnena izolacija je imela z največjim deležem pepela, največjo toplotno stabilnost ter najnižjo ceno. Lesna izolacija pa je imela najbolj temperaturno stabilen fiksni ogljik ter najnižjo vgrajeno energijo (EE).In addition to heat transfer, economic considerations, strength and stability, the choice of the right thermal insulation for a building should also take into account optimal performance and minimised environmental impact. There are several different types of thermal insulation on the market, ranging from the most commonly used glass wool, rock wool, EPS and XPS to natural materials such as wool, hemp, cellulose, flax, etc., which have different technical characteristics such as thermal and acoustic insulation, fire performance, ability to control ambient humidity and carbon footprint.
The master\u27s thesis deals with three natural insulations, sheep wool, cellulose insulation (wood wool) and hemp insulation, which have the advantage of a relatively low environmental impact, a contribution to indoor comfort by reducing air pollution and good fire resistance, either due to the material properties themselves or due to the addition of flame retardants. The proximate analysis of these samples was determined using TA methods, namely EGA, TGA, DTA, DTG. The thermal stability of the three thermal insulation samples was determined using TA methods depending on variation of the mass of the sample and the thermal changes in the sample during the thermal loading of the sample. The EGA method, which combines a thermogravimetric analyser (TGA) and a quadrupole mass spectrometer (QMS), was used to determine the composition of the volatile components of the samples. The aim of the research is to determine which of the natural insulations considered is the best choice in terms of proximate composition, thermal stability and cost, taking into account also the carbon footprint (GWP) and embodied energy (EE) of each insulation sample.
The results of the thermal analysis methods showed that sheep\u27s wool, wood wool and hemp insulation and decompose in a three – step process. The first stage involves the loss of moisture, the second stage the formation of volatile components or pyrolysis gases, the third stage the combustion of fixed carbon and the residue after thermal treatment is ash. The first two mass changes of the sample take place in an inert atmosphere (argon) and the third in an oxidising atmosphere (argon and oxygen) in a temperature range from 40 °C to 900 °C, recording the thermal decomposition components of the sample.
The findings showed that hemp insulation had a higher thermal stability due to the higher pyrolysis gas generation temperature and the lowest (negative) carbon footprint (GWP). Wool insulation had with the highest ash content, the highest thermal stability and the lowest cost. Wood insulation, on the other hand, had the most thermally stable fixed carbon and the lowest embodied energy (EE)
Psychological aspect of the influence of the color of light on human
Get PDFSvetloba ima močan vpliv na naše telo. Ne samo količina svetlobe pač pa tudi njena barva. V nalogi preučite, kako barva svetlobe vpliva na delovanje človeškega telesa in kako jo lahko uporabimo za izboljšanje svetlobnih razmer na delovnih mestih.Light has a profound effect on our body. Not only the amount of light but also its colour. In the thesis, explore how the colour of light influences the functioning of the human body and how it could be used to improve lighting conditions in workplaces
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
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