185 research outputs found
Black Hole Mass Estimation in Type 1 AGN: H vs. Mg II lines and the role of Balmer continuum
Here we investigate the H and Mg II spectral line parameters used for
the black hole mass (M) estimation for a sample of Type 1 Active
Galactic Nuclei (AGN) spectra selected from the Sloan Digital Sky Survey (SDSS)
database. We have analyzed and compared the virialization of the H and
Mg II emission lines, and found that the H line is more confident virial
estimator than Mg II. We have investigated the influence of the Balmer
continuum emission to the M estimation from the UV parameters, and
found that the Balmer continuum emission can contribute to the overestimation
of the M on average for ~ 5% (up to 10%).Comment: 9 pages, 3 figures, Accepted for publication in Frontiers in
Astronomy and Space Science
Synthetic Population of Interstellar Objects in the Solar System
The discovery of the first two macroscopic interstellar objects (ISOs)
passing through the Solar System has opened entirely new perspectives in
planetary science. The exploration of these objects offers a qualitatively new
insight into the processes related to the origin, structure and evolution of
planetary systems throughout the Galaxy. Knowledge about these phenomena will
greatly advance if current and future sky surveys discover more ISOs. On the
other hand, the surveys require better characterization of this population in
order to improve their discovery algorithms. However, despite their scientific
significance, there is still no comprehensive orbital model of ISOs in the
Solar System and computationally efficient algorithm for generating their
synthetic representations that would respond to these increasing needs.
Currently available method for generating synthetic populations cannot fully
take into account important phenomena, such as gravitational focusing and the
shielding effect of the Sun. On the other hand, this method is also
computationally far too demanding to be used for systematic exploration of the
ISO population. This paper presents an analytical method for determining the
distributions of the orbital elements of ISOs, as well as computationally
efficient algorithm for generating their synthetic populations, based on the
multivariate inverse transform sampling method. The developed method is several
orders of magnitudes more efficient than the available method, depending on the
size of the synthetic population. A Python implementation of the method is
freely available and can be used to generate synthetic populations of ISOs with
user-defined input parameters.Comment: to be published in Astronomy and Computin
Differences in morphological properties between the olivine group minerals formed in natural and industrial processes
Olivines are a large isomorphic series of minerals, belonging to silicates group. Regardless of their chemical composition, any of these minerals can be formed both in natural and industrial processes. The aim of this work is to describe these minerals and differences of morphological properties between the olivines formed in nature, and those formed as byproducts of some industrial processes , as Process Metalurgy-Ironmaking. The olivines whose formation is tied to rock masses (natural process) and the olivines genetically tied to industrial processes of black metallurgy slags (process metallurgy-Ironmaking) are shown in this paper. The morphological properties of these minerals and their differences have been analyzed by optical microscopy in refracted and in reflected light.
Comparison of Two Felling & Processing Methods in Beech Forests
In this research, two motor-manual felling & processing methods were compared, assortment and half-tree length, in beech stands. Investigation was done in two compartments in the northern part of Bosnia and Herzegovina (B&H), where four sample plots were chosen that differed by felled tree diameter and harvesting method. On the sample plots A1 and B1 assortment harvesting method was performed and on the sample plots A2 and B2 half-tree length method. In the study, 318 trees were felled in total, of which 163 by the assortment method and 155 by the half-tree length method. With the increase of DBH, productivity was constantly increasing and it was higher when the half-tree length method was applied than the assortment method. The main reason why half-tree length was more productive was the fact that some working operations, like production and stacking of fuel wood, were avoided or minimized
Uloga jezika u izgradnji hrvatskoga nacionalnog identiteta u Istri: s primjerima iz odabrane istarske periodike u 19. i 20. stoljeÄu
In this paper, we address the building of Croatian national identity in several Istrian newspapers of the 19th and 20th century, from the earliest publishing enterprises to 1955. This was a time of complex political circumstances and changes in the Istrian region, when an important role in the process of language planning and in language policy was played, among others, by publications that influenced the formation of the public language: NaÅ”a sloga, Hrvatski list, PuÄki prijatelj, Istarska rijeÄ, and Hrvatski glas. Texts dedicated to bilingualism and trilingualism, Germanization and Italianization of language in education, administration, post offices, seafaring, railway, Church, and other forms of both public and private communication reflect clearly the language policy of the period of building Croatian national identity. In the atmosphere marked by the general dissolution of cultural institutions (schools, peopleās associations, libraries, societies, and journals) in both Croatian and Slovene ā which helped the assimilation of the local population considerably ā the emergence of publications in Croatian was extremely important for the language. Additionally, they were an important source of information and familiarization of the population with legal regulations concerning the status of the Croatian language, whereby these media became a powerful tool of spreading the rhetoric of the ruling parties that created or tried to influence the linguistic reality and practices.U radu se osvrÄemo na tekstove odabranih istarskih glasila koja su tematizirala jezik, a imala su ulogu u oblikovanju hrvatskoga nacionalnog identiteta u Istri u 19. i u prvoj polovici 20. stoljeÄa, od prvih nakladniÄkih pothvata do 1955. godine. Vrijeme je to vrlo složenih politiÄkih prilika i mijena na istarskome podruÄju, a važnu ulogu u procesima izgradnje hrvatskoga nacionalnog identiteta imaju i glasila koja utjeÄu na oblikovanje javnoga jezika: NaÅ”a sloga, Hrvatski list, PuÄki prijatelj, Istarska rijeÄ i Hrvatski glas. Iz tekstova o dvojeziÄnosti i trojeziÄnosti, germanizaciji i talijanizaciji jezika u Å”kolstvu, administraciji, pomorstvu, poÅ”tama, željeznici, crkvi te u drugim oblicima javne, ali i privatne komunikacije može se iÅ”Äitati važnost jeziÄne politike vremena u izgradnji hrvatskoga nacionalnog identiteta. U ozraÄju posvemaÅ”njega gaÅ”enja kulturnih institucija (Å”kola, narodnih domova, knjižnica, druÅ”tava i novina) na hrvatskome i slovenskome jeziku, Å”to je uvelike pripomoglo odnaroÄivanju domaÄega stanovniÅ”tva, pojava publikacija na hrvatskome jeziku bila je viÅ”estruko važna za hrvatski jezik. TakoÄer, važan su izvor informacija i upoznavanja stanovniÅ”tva sa zakonskim odredbama kojima se pokuÅ”ava regulirati status hrvatskoga jezika Äime ovi mediji postaju snažnim alatom u mijenama jeziÄne prakse
Water - a significant natural resource of Croatia's economy
Voda je najzastupljenija tvar u graÄi svih živih biÄa, pa možemo reÄi da je voda život, vodom zadovoljavamo osnovnu ljudsku potrebu, voda je i transportni medij, sredstvo za proizvodnju energije, uzgajaliÅ”te hrane, roba, lijek, prostor za rekreaciju, voda je Äesta granica izmeÄu država, kultura i religija, ali voda isto tako može biti opasnost.
Zbog porasta broja ljudi na Zemlji i zbog poveÄanih potreba za vodom, kao posljedice porasta životnog standarda, promjena životnih navika i poljoprivredne proizvodnje, potroÅ”nja vode u svijetu neprestano raste.
Problemi s kojima smo suoÄeni jednim dijelom su izazvani od strane Äovjeka i njegovog neodgovornog koriÅ”tenja tog resursa, dok s druge strane, svjedoci smo sve veÄih klimatskih promjena Äije se posljedice odražavaju i na vodu.
Äovjek kao pojedinac nije dovoljno osvijeÅ”ten po pitanju održivog koriÅ”tenja vode. StanovniÅ”tvo bogatijih zemalja mnogo je rastroÅ”nije i ne obraÄaju pažnju na potroÅ”nju vode i naÄine kojima se odnose prema vodi, dok u siromaÅ”nijim zemljama postoje ljudi koji ni nemaju pristup pitkoj vodi. Da bi izbjegli neželjene prognoze bliske buduÄnosti, upravljanje vodom mora ukljuÄivati koncept održivog razvoja.
Ono Å”to danas nije teÅ”ko zakljuÄiti jest da voda zbog svog znaÄaja nije samo izvor života, nego na žalost i izvor profita, a samim time i oružanih sukoba.
Prema zakonu iz 2010. godine, u najÅ”oj državi opskrbu pitkom vodom mogu obavljati samo trgovaÄka druÅ”tva u vlasniÅ”tvu jedinica lokalne samouprave ili države. Dok suprotno tome postoje zemlje koje su dopustile privatnim korporacijama posjedovanje vodovoda i vodocrpiliÅ”ta, te je iskustvo pokazalo kako se privatni vlasnik prema toj Äinjenici ne odnosi kao prema posjedovanju opÄeg dobra, veÄ iskljuÄivo kao prema sredstvu zarade.Water is the most common substance in the body of all living beings, so we can say that water is life.
With water we fulfill the basic human need, water is a transport medium, it is used for energy production, a grocery breeding farm, a good, a drug, a recreation area, water is a common border between states, cultures and religions, but water can also be a danger.
Becouse of the growth of number of people on the Eart and also becouse of the growing needs for water, as a the consequences of rising living standards, changes in living habits and agricultural production, world water consumption is constantly increasing.
The problems we are faceing partly are caused becouse we are unresponsably using that resource, but from the other angle, we are witnesses of growing climate changes whose aftermath are beeing reflected also on the wather.
Human as an individual is not enough conscious abouth sustainable water using. Population of wealthy countries is much more wasteful and they don't pay atention on water consumption ant the ways they treat water, while in poor countries there are people that do not have access to drinking water. To avoid unwanted forecasts of the near future, water management must include the concept of sustainable development.
Today is not hard to say that water is not only a source of life but also a source of profits and, therefore, armed conflicts.
According to the law of 2010, in our country drinking water can only be supplied by the state-owned companies. On the other side, there are countries that have allowed private corporations to own water supply, and experience has shown that a private owner does not relate to that fact as having a general good but exclusively as a means of earning
JeziÄnometodiÄki predloÅ”ci u nastavi hrvatskoga jezika
Nastavni predmet Hrvatski jezik sastoji se od nastavnih podruÄja poÄetnog Äitanja i pisanja, hrvatskog jezika u užem smislu, jeziÄnog izražavanja, književnosti i medijske kulture. Tekstove kojima se koristimo u sklopu nastave Hrvatskoga jezika nazivamo jeziÄnometodiÄkim predloÅ”cima. DidaktiÄki osmiÅ”ljeni i usustavljeni tekstovi polaziÅ”te su za spoznavanje književnoumjetniÄkih, ali i jeziÄnih nastavnih sadržaja. Stoga Äe se za svaki od ovih podruÄja koristiti i razliÄita vrsta izvora znanja, odnosno konkretnije, metodiÄkog predloÅ”ka. U nastavi književnosti govorimo o pjesmi, dramskom tekstu, tekstu u prozi ili esejistiÄkom tekstu. U nastavi jezika koristit Äemo se pogodnim književnim tekstom, ali takoÄer može biti rijeÄ i o posebno napisanom tekstu ili didaktiÄkom stripu koji je zasiÄen pojavom koja se usvaja. U nastavi medijske kulture, metodiÄki Äe predložak biti neko medijsko djelo (kazaliÅ”na predstava, televizijska ili radio emisija, film itd.)Croatian language as school subject consists of several teaching areas: initial reading and writing, the Croatian language in the narrow sense, language expression, literature and media culture. The texts we use in the teaching of the Croatian language are called lingual-didactic templates. Didactically designed and arranged texts are the starting point for learning, both literary and language teaching contents. Therefore, for each of these areas, different types of knowledge sources (a
methodical templates) will be used. In the teaching of literature we talk about poetry, dramatic text, prose text, or essayist text. In language teaching, we will use appropriate literary text, but it may also be a specially written text or didactic strip that is saturated with the phenomenon that is being learned. In the teaching of media culture, didactic template will be some media work (theater play, television or radio show, movie, etc.
Commercialization of non-wood forest products on the territory of AP Vojvodina
In the previous utilization of natural resources in forestry as an economic activity, timber exploitation was always the dominant part, and the utilization of other forest products was partly neglected. Nowadays, non-wood forest products (NWFPs) occupy an increasingly significant position in the forestry sector in numerous countries, so that the revenue from their utilization approaches the returns realized by the classical production of timber products. The research performed in Vojvodina, on the sample of six enterprises dealing with NWFP purchase, processing and sale was aimed at the analysis of their market activities to create the image of the market of this group of products. After the study data were analyzed by dynamic statistical methods, the changes in the activities on purchase, the domestic sales and export sales between 2004 and 2010 were presented and future projects were visualized. The research in the form of questionnaire included the quantities of purchased raw materials, the scope of production and sales, both in the domestic, and in foreign markets, as well as the prices of final products. Some species of medicinal plants were purchased on the territories of Croatia and Macedonia, and the purchasing network in the domestic market was remarkably wide and it included predominantly: NiÅ”, Svrljig, Äoka, Apatin, PanÄevo, Ruma, Boljevac, Kanjiža, etc. The most significant growth was realised in the purchase of a mixture of medicinal plants. Also significant are the purchased quantities of mint, which on average increased by 7.9 t and rose hip by 5.5 t per year. During the study period, the domestic sale of all species of herbal teas and medicinal plants increased significantly, while spices and honey were subject to a fluctuation in sales quantity. Average algebraic deviation of the original final NWFP sale value from the arithmetic mean accounts for 3.48%. With the significance level of 95%, it is estimated that the sale in 2012 will range between 3049.19 and 3343.95 t, under the condition that the sale continues its quadratic trend. Based on the quadratic trend, and with the significance level of 95%, it can be foreseen that the value of export in 2012 will range from 133.01 to 250.07 t. As for the time interval from 2004 to 2010, the average export amounted to 260.07 t, which encompassed primarily medicinal and aromatic plants, spices and honey. During the study period, export decreased on average by 7.03% (20.75 t per year)
Synthetic Detections of Interstellar Objects with The Rubin Observatory Legacy Survey of Space and Time
The discovery of two interstellar objects passing through the Solar System,
1I/`Oumuamua and 2I/Borisov, implies that a galactic population exists with a
spatial number density of order au. The forthcoming Rubin
Observatory Legacy Survey of Space and Time (LSST) has been predicted to detect
more asteroidal interstellar objects like 1I/`Oumuamua. We apply recently
developed methods to simulate a suite of galactic populations of interstellar
objects with a range of assumed kinematics, albedos and size-frequency
distributions (SFD). We incorporate these populations into the objectsInField
(OIF) algorithm, which simulates detections of moving objects by an arbitrary
survey. We find that the LSST should detect between asteroidal
interstellar objects every year (assuming the implied number density), with
sensitive dependence on the SFD slope and characteristic albedo of the host
population. The apparent rate of motion on the sky -- along with the associated
trailing loss -- appears to be the largest barrier to detecting interstellar
objects. Specifically, a relatively large number of synthetic objects would be
detectable by the LSST if not for their rapid sky-motion (
d). Therefore, algorithms that could successfully link and detect
rapidly moving objects would significantly increase the number of interstellar
object discoveries with the LSST (and in general). The mean diameter of
detectable, inactive interstellar objects ranges from m and
depends sensitively on the SFD slope and albedo.Comment: 13 pages, 11 figures, accepted for publication in the Planetary
Science Journa
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