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Influence of flood-control reservoir Brezje on flood waters of the river Horjulščica
No full textThe aim of this assignment is to determine how flood-control reservoir Brezje influences the flood wave on the river Horjulščica. Because of growing urban environment around the city of Ljubljana there is less and less natural environment for natural river flow. One example of this problem is the river Gradaščica. It flows through an area which is very much endangered by floods. This was already shown in the past when the flooded river Gradaščica caused extensive damage. Lately, there are lots of different flood-control projects in developing – they would lower the risk of floods in this area. One of these projects – the influence of flood- control reservoir Brezje – is studied in this diploma work. During this assignment hydrological and hydraulic models were made. The hydrological model computes hydrographs based on data of precipitation and composition of terrain. The hydrographs are then used in hydraulic model that is created for the area of flood-control reservoir Brezje. As a result of this model hydrographs for area of flood-control reservoir Brezje are given. The changes of output hydrographs are based on different manoeuvres of sluice gates which are halting the free discharge of the water and thus affect the flood wave of the river Horjulščica. The results of these models tell us that flood-control reservoir Brezje has a positive influence on 100-years flood waters and because of that floods are less likely to occur in downstream areas
Impact of water level pivot point on operation of HPP reservoirs
Full text linkZa zagotavljanje varnega delovanja v vseh razmerah imajo pretočne hidroelektrarne določen
način obratovanja, ki velja za razmere ob zagonu objekta. Na podlagi izbranega načina
delovanja je konstruirana denivelacijska krivulja, skladno s katero posamezni objekt deluje.
Posledica izbranega načina obratovanja in denivelacijske krivulje je oblikovanje gladinskega
vrtišča v akumulaciji. Vrtišče predstavlja tisto točko v akumulaciji, kjer gladina ostaja
konstantna kljub povečanju oz. manjšanju pretoka v vodotoku in se pojavi samo v času, ko
hidroelektrarna deluje skladno z denivelacijsko krivuljo. Z umestitvijo hidroelektrarne in s
tem vzpostavitvijo zajezitve vodotoka se spremenijo hidravlične razmere na vodotoku. V
akumulaciji se prične odlaganje sedimentov in s tem spreminjanje batimetrije akumulacije. V
nalogi je s hidravličnem modeliranjem preverjen vpliv sedimentacije na začetno lokacijo
gladinskega vrtišča in s tem na obratovanje hidroelektrarn. Najprej so izvedeni izračuni za
teoretični primer hidroelektrarne z akumulacijo s poenostavljeno geometrijo, za katero je
preverjen vpliv dvigovanja dna in spremembe hidravlične hrapavosti ter vpliv teh sprememb
na predpisani način obratovanja. Z izvedbo izračunov so pridobljene osnovne ugotovitve,
kako se ob različnih spremembah obnaša lokacija gladinskega vrtišča in kakšen vpliv ima to
na samo obratovanje. Pridobljene ugotovitve so nato preverjene še z izdelavo hidravličnega
modela območja hidroelektrarne HE Boštanj. Glede na rezultate izračunov iz obeh izdelanih
primerov, je izvedena sinteza ugotovitev, ki nam pove, kako odlaganje/odnašanje plavin
vpliva na lokacijo gladinskega vrtišča, kakšne so informacije, ki jih poda položaj vrtišča in na
kakšen način lahko s spremljanjem položaja vrtišča izboljšamo obratovanje HE.To ensure safe operation of hydropower plant (HPP) in all conditions, every HPP has to have
defined operation concept. Operation concept is always defined for starting conditions in
which HPP and its reservoir starts to operate. Based on the selected operation concept a set of
operating rules is applied. As a result of the selected operating concept and designed set of
operation rules a water level pivot point appears in HPP reservoir. Pivot point represents the
point in the reservoir, where the water level remains constant, regardless the increase or.
decrease of the flow in the river. Pivot point appears only at times, when HPP operates in
accordance with designed set of operation rules. But with the construction of HPP, hydraulic
conditions of the river are altered. Consequently of that a process of sedimentation begins in
the reservoir. In this assignment the impact of sedimentation on the initial location of water
level pivot point and thus on starting operation concept is analyzed with methods of hydraulic
modeling. Hydraulic calculations are performed for theoretical example of HPP in a reservoir
with simplified geometry. Changes in reservoir\u27s bottom and hydraulic roughness are
observed and their impact on the starting operating concept is investigated. By performing
calculations for this example, we obtaine basic knowledge regarding how the various changes
influence the water level pivot point and the level of impact on operation concept. The results
are later validated with calculations for the hydraulic model of HPP Boštanj. Based on the
results from both calculations, the analysis were made. The analysis explains the impact of
sedimentation on the location of water level pivot point, the implications on operation concept
and how the effects can be mitigated
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
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
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