1,720,954 research outputs found
Separation sequence synthesis
No full textSinteza separacijskog niza ključan je korak u projektiranju kemijskih procesa. Većina troškova opremanja i rada postrojenja otpada upravo na separacijske uređaje, stoga je pravilan odabir metode separacije i optimiranje rada separacijskog niza bitno, ne samo zbog smanjenja troškova rada sustava za separaciju, već i za ukupnu profitabilnost cjelokupnog proizvodnog procesa. Najrašireniji i energetski najintenzivniji separacijski proces je destilacija, stoga se u ovom radu obrađuje sinteza niza destilacijskih kolona. Uz algoritam za izbor tlaka te tipa kondenzatora, prikazana su iskustvena pravila za odabir najboljeg niza razdvajanja. Uz to prikazana je metoda marginalne vrijednosti protoka pare (marginal vapor rate), kojom je moguće na jednostavan način približno odrediti ukupne troškove procesa destilacije, što omogućuje brzu ocjenu pojedinog redoslijeda, bez detaljnog modeliranja. Metodologija je predstavljena na primjeru sinteze destilacijskog niza za razdvajanje trokomponentnih smjesa.Separation sequence synthesis is the key step in designing chemical processes. Unit operations purchase costs, as well as their operating expenses comprise major part of the total plant capital expenses. Therefore, proper selection of the separation method and optimization of the separation sequence is important for profitability of the entire production process. The most widely applied and energy intensive process for fluid separation is distillation – therefore, the synthesis of a distillation sequence is being discussed in this thesis. Besides an algorithm for selection of condenser type and pressure, heuristic rules for distillation sequence synthesis are presented. In addition, the marginal vapour rate method for approximate distillation process cost determination is presented, which enables quick assessment of a sequence, without the need for rigorous modelling. The methodology is presented on a three-product separation case
Analysis of the plug-flow reactor for ammonia sulphate synthesis in NPK-2 plant
No full textU ovom radu provedena je analiza rada cijevnog reaktora za proizvodnju amonijeva sulfata u postrojenju NPK-2 u Petrokemiji d.d. iz Kutine. U teorijskom dijelu rada dan je pregled vrsti, karakteristika te procesa proizvodnje gnojiva s naglaskom na amonijev sulfat. Uz to, opisano je djelovanje mineralnih gnojiva u primjeni te njihovo značenje u modernoj poljoprivredi. Poseban naglasak stavljen je na primjenu i djelovanje amonijeva sulfata. Cilj rada bilo je proučiti sintezu amonijeva sulfata i simulirati proces proizvodnje. Provedeno je simulacijsko istraživanje sinteze amonijeva sulfata pomoću procesnog simulatora CHEMCAD. U radu je razvijen model simulacije proizvodnje amonijeva sulfata za kapacitet proizvodnje od 15 t/h, te simulacija pročišćavanja otpadnih plinova pomoću skrubera.In this paper, an analysis of the operation of a tube reactor for the production of ammonium sulfate in the NPK-2 plant at Petrokemija d.d. from Kutina. The theoretical part of the paper gives an overview, characterization and processing of fertilizer production with emphasis on ammonium sulfate. In addition, the effect of mineral fertilizers in application and what is known in modern agriculture is described. Particular emphasis is placed on the example of the action of ammonium sulfate. The aim of the study was to study the synthesis of ammonium sulfate and to simulate the production process. A simulation study of ammonium sulfate synthesis using a CHEMCAD process simulator has been demonstrated. A simulation model for the production of ammonium sulfate was developed for a production capacity of 15 t/h, and a simulation of waste gas treatment using a scrubber
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
- …
