1,720,956 research outputs found
Rekonstrukcija postojećih evaporativnih kondenzatora industrijskog rashladnog postrojenja
Full text linkU ovom radu analizirano je postojeće amonijačno rashladno postrojenje koje se koristi za tehnološke potrebe hlađenja u industriji mlijeka. Postavljen je rashladni proces sustava hlađenja i dizalice topline. Napravljen je plan rekonstrukcije evaporativnih kondenzatora zbog njihove dotrajalosti, kao i još nekih elemenata kako bi se optimizirao sustav. Izvršen je i termodinamički proračun evaporativnog kondenzatora kapaciteta 1000 kW, a za cijeli plan rekonstrukcije je napravljen i ekonomski proračun kao i plan povrata investicije
Reconstruction of current evaporative condensers in industrial refrigeration system
Full text linkU ovom radu analizirano je postojeće amonijačno rashladno postrojenje koje se koristi za tehnološke potrebe hlađenja u industriji mlijeka. Postavljen je rashladni proces sustava hlađenja i dizalice topline. Napravljen je plan rekonstrukcije evaporativnih kondenzatora zbog njihove dotrajalosti, kao i još nekih elemenata kako bi se optimizirao sustav. Izvršen je i termodinamički proračun evaporativnog kondenzatora kapaciteta 1000 kW, a za cijeli plan rekonstrukcije je napravljen i ekonomski proračun kao i plan povrata investicije.In this paper the existing ammonia cooling plant used for technological cooling needs in the dairy industry is analyzed. The process of the cooling system and the heat pump is calculated. A plan for the reconstruction of the evaporative condenser was made because of their wear and tear, as well as some other elements in order to optimize the system. A thermodynamic calculation of evaporative condenser with a capacity of 1000 kW was carried out, and for the entire reconstruction plan, an economic budget as well as an investment return plan was made
Zamjena radne tvari R-404A s radnom tvari srednjeg utjecaja na globalno zatopljenje u rashladnom uređaju za potrebe hlađenja na temperature više od 0 °C
No full textPod utjecajem F-gas uredbe, radne tvari s visokim GWP-om postaju zabranjene u uporabi. Zbog toga se traže alternativne radne tvari s nižim GWP brojem kako bi se provela zamjena .
U ovom radu istražene su komercijalno dostupne radne tvari HFC skupine sa srednjim GWP faktorom te je napravljen termodinamički proračun procesa s radnom tvari R-404A i zamjenskim radnim tvarima R-448A, R-449A i R-407F. Opisani su prednosti i nedostaci pri zamjeni radne tvari kao i postupak same zamjene. Navedene su komponente sustava s opisom i ulogom te dijelovi koji zahtijevaju zamjenu jer nisu kompatibilni s novom radnom tvari
Retrofitting of a R-404A condensing unit to a fluorinated medium GWP refrigerant for a medium temperature commercial application
No full textPod utjecajem F-gas uredbe, radne tvari s visokim GWP-om postaju zabranjene u uporabi. Zbog toga se traže alternativne radne tvari s nižim GWP brojem kako bi se provela zamjena .
U ovom radu istražene su komercijalno dostupne radne tvari HFC skupine sa srednjim GWP faktorom te je napravljen termodinamički proračun procesa s radnom tvari R-404A i zamjenskim radnim tvarima R-448A, R-449A i R-407F. Opisani su prednosti i nedostaci pri zamjeni radne tvari kao i postupak same zamjene. Navedene su komponente sustava s opisom i ulogom te dijelovi koji zahtijevaju zamjenu jer nisu kompatibilni s novom radnom tvari.Under the influence of F-gas regulation, refrigerants with high GWP factor are becoming banned to use. Therefore, alternative refrigerants with lower GWP factor are sought for retrofitting.
In this study it is looked into commercially available HFC refrigerants with medium GWP factor and thermodynamic calculation of process with refrigerant R-404A and its retrofits R-448A, R-449A and R-407F is presented. Advantages and disadvantages are described for each refrigerant as well as the procedure of retrofitting. Components of a system are listed with description and role as well as parts that require replacement because they are not compatible with a new refrigerant
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
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