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Samohodni aplikator za ubrizgavanje tečnog azota u usevu pšenice na usitnjenim žetvenim ostacima pirinča
No full textIn order to reduce nitrogen losses sustained in broadcasting of urea under
high rice straw mulched wheat crop and to enhance crop yield, a self propelled spoke
wheel nitrogen applicator for injecting nitrogen in liquid form beneath the soil surface
was designed, developed and evaluated under actual field conditions. The machine
comprised four sets of spoke wheel having radial injectors attached to a distribution hub
with inline mounted flow control valve and cut-off system. Constant supply of liquid
urea to the distribution hub by means of a piston pump produced pressure adequate to
expel urea solution through the flow control valve as it opened. The opening and closing
of flow control valve was regulated through a specially designed lever and stationery
cam. The average field capacity and efficiency of the machine were found to be 0.36
ha·h-1 and 88.9%, respectively. Yield and nitrogen use efficiency (NUE) of wheat crop
fertilized with spoke wheel nitrogen applicator was 20 and 47 % respectively higher than
that of broadcasting method of nitrogen application. Lower nitrogen accumulation in
mulch and higher nitrogen uptake in wheat crop indicated reduced nitrogen losses in
case of point injected nitrogen application over broadcasting. Hence, spoke wheel
nitrogen applicator acquires a promising option not only for enhancing crop yield but
also environment protection.Sa ciljem smanjenja gubitaka azota pri ubacivanju uree pod usitnjene
žetvene ostatke radi povećanja prinosa, konstruisan je samohodni aplikator za
ubrizgavanje tečnog azota pod površinu zemljišta. Mašina se sastoji od četiri kompleta
točkova sa paocima i injektorima postavljenim na haubu sa ugrađenim ventilom za
kontrolu protoka i isključenje sistema. Konstantan dotok tečne uree do distributera preko
klipne pumpe obezbeđen je odgovarajućim pritiskom za izbacivanje rastvora uree kad je
kontrolni ventil otvoren. Otvaranje i zatvaranje kontrolnog ventila je regulisano
specijalno konstruisanom ručicom. Srednji poljski kapacitet i efikasnost mašine su
iznosili 0.36 ha·h-1 i 88.9%, redom. Prinos i efikasnost iskorišćenja azota (NUE) kod
pšenice đubrene ovim aplikatorom azota bili su 20 i 47%, redom, viši nego pri
uobičajenom rasturanju azota. Niža akumulacija azota u malču i više usvajanje azota kod
pšenice ukazuju na manje gubitke azota kod tačkastog ubrizgavanja azota u odnosu na
rasturanje. Tako ovaj aplikator azota predstavlja povoljniju opciju, ne samo za povećanje
prinosa nego i za zaštitu okoline
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
Razvoj i standardizacija mernog mehanizma na uređaju za aplikaciju azota (tečne uree) tačkastim ubrizgavanjem
No full textThe existing method of broadcasting urea on straw mulched direct seeded
wheat crop is susceptible to nitrogen losses. Nitrogen (liquid urea) applicator could be
used to forestall the hazards of nitrogen loss and a metering mechanism for nitrogen
(liquid urea) is currently not available. Hence, a nitrogen (liquid urea) metering
mechanism was developed and tested in the laboratory. The operating pressure and
peripheral speed of metering system were found to have significant effect on the
discharge rate of metering mechanism. The discharge rate of the metering system was
directly correlated with operating pressure and indirectly correlated with peripheral
speed of the metering system. Based on the performance parameters, a peripheral speed
of 0.70 m·s-1 (forward speed of 2.5 km·h-1), operating pressure of 3 kg·cm-2 and 2.095
l·ha-1 application rate of urea solution were selected for field operation of nitrogen
(liquid urea) applicator. The outcome of this study will encourage the use of point
injected nitrogen (liquid urea) applicator on straw mulched crops.Postojeći metod primene uree na površini tretiranoj malčom slame sa
direktno sejanom pšenicom je podložan gubicima azota. Azot (tečna urea) može biti
apliciran kako bi se izbegao rizik od gubitka azota, ali merni mehanizam za azot (tečnu
ureu) trenutno nije dostupan. Zato je razvijen i u laboratorijskim uslovima testiran uređaj
za merenje azota. Radni pritisak i obimna brzina mernog mehanizma imali su značajan
uticaj na normu aplikacije. Intenzitet pražnjenja je bio u direktnoj korelaciji sa radnim
pritiskom i u obrnutoj korelaciji sa obimnom brzinom mernog sistema. Na osnovu
ispitivanih veličina, za rad u poljskim uslovima određeni su sledeći parametri: obimna
brzina od 0.70 m∙s-1 (radna brzina od 2.5 km∙h-1), radni pritisak od 3 kg∙cm-2 i norma
aplikacije rastvora azota (tečne uree) od 2.095 l∙ha-1. Rezultati istraživanja u ovoj studiji
će unaprediti upotrebu uređaja tačkastu aplikaciju azota (tečne uree) na parcelama sa
usevima na slamenom malču
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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