38 research outputs found
Evaluacija investicionih performansi portfolija sastavljenih od tematskih i sektorskih investicionih fondova na tržištu akcija u SAD-u
Rad ima dvostruko postavljene ciljeve. Naučni cilj istraživanja je dekomponovanje, analiziranje i interpretiranje investicionih performansi hipotetičkih portfolija sastavljenih od investicionih fondova sa definisanim univerzumima akcija, na osnovu zvanično naznačenih investicionih strategija. Društveni cilj istraživanja je prezentovanje adekvatne metodologije za evaluaciju investicionih performansi, koja bi bila osnov za postavljanje regulatornih standarda, ali isto tako i pružila vrednost za široku bazu internih i eksternih činioca. Primenjena metodologija istraživanja podrazumevala je dve grupe modela za pripisivanje investicionih performansi, a to su faktorski, kao i modeli bazirani na imovini. U okviru prvopomenute grupe korišćeni su: model za vrednovanja kapitalne aktive, trofaktorski Fama-French model, Carhart model i petofaktorski Fama-French model. U okviru drugopomenute grupe korišćeni su Brinson-Hood-Beebower i Brinson-Fachler modeli, kao i geometrijski modeli. Istraživanje koje se bavi tematskim investicionim fondovima obuhvatilo je 240 pojedinačnih fondova u Sjedinjenim Američkim Državama. Investicioni fondovi su analizirani na individualnom nivou, ali i na nivou portfolija na osnovu 2x2 matrice tržišne kapitalizacije i investicionog stila. Svaki od analiziranih portfolija sastavljen je od 60 investicionih fondova date investicione tematike. Korišćenjem faktorskih modela otkriveni su faktori koji su prevladali na tržištu. Takođe, korišćenjem modela baziranih na imovini potvrđeni su rezultati faktorskih modela za dominantan investicioni stil. Za sve posmatrane faktore bilo je moguće utvrditi uticaj na portfolije investicionih fondova i pojedinačne investicione fondove. Uticaji faktora koji su u skladu sa očekivanjima inicijalnih originalnih modela su: tržišna premija, veličina kompanije, momentum, kao i profitabilnost kompanije. Uticaji faktora koji nisu u skladu sa očekivanjima inicijalnih originalnih modela su: investicioni stil i konzervativnost investiranja kompanije. Rezultati pripisivanja investicionih performansi takođe su ukazali na heterogenost ostvarenih dodatnih prinosa, posmatranih po sektorima. Postoji i prisustvo momentuma u ostvarenim dodatnim prinosima po sektorima. Ovakvi rezultati sugerišu da postoje određeni aspekti investicione filozofije koji su pretočeni u investicione strategije koji nisu samo rezultat pasivnog praćenja sektora na osnovu ostvarivanja izloženosti. Na osnovu rebalansirana portfolija, u slučaju istraživanja na godišnjem nivou, bilo je moguće značajno unaprediti prinose ukoliko se može predvideti prisustvo dominantnog investicionog stila na tržištu. Tome idu u prilog rezultati na osnovu izloženosti tematskim investicionih fondova i godišnji efekti sektorske alokacije u istraživanju namenjenom sektorskim investicionim fondovima. Analizom ostvarene izloženosti prema posmatranim faktorima, kao i analizom same strukture portfolija bilo je moguće utvrditi pojavu eventualnih nekonzistentnosti u odnosu na navedene investicione strategije. Na osnovu analize rezultat istraživanja zaključeno je da postoji visok nivo konzistentnosti na portfolio i individualnom nivou na osnovu uticaja faktora iz primenjenih modela. Primena modela baziranih na imovini, koji koriste podatke o strukturi portfolija i investicionog repera, omogućila je da se dobiju rezultati koji mogu biti od veće koristi budući da se mogu bolje uskladiti sa procesom donošenja investicionih odluka. Komplementarnost primene faktorskih modela sa modelima baziranim na imovini omogućila je da se potvrde pojedini prisutni trendovi na tržištu, ali je i dala uvid u aspekte koji nisu bili mogući putem samo korišćenja faktorskih modela. Nedostaci aritmetičkih modela za pripisivanje investicionih performansi baziranih na višestrukim periodima, prevaziđeni su primenom geometrijskih modela. To je rezultiralo uspešnim povezivanjem višeperiodičnih prinosa putem modela za geometrijsko pripisivanja, bez reziduala. Time je obezbeđena konzistentnost efekata pripisivanja po osnovu različitih perioda prikazivanja
Obrada otpadne vode tekstilne industrije u anaerobno-aerobnom membranskom bioreaktoru i postupkom naknadnog ozoniranja
U ovom istraživanju procijenjena je učinkovitost rada poluindustrijskog uređaja za obradu realne otpadne vode tekstilne industrije nakon procesa bojadisanja primjenom biološko-fizikalnog procesa te naknadnog kemijskog procesa. Provedeni biološko-fizikalni proces obrade sastojao se od biološkog anaerobno-aerobnog procesa te procesa ultrafiltracije poznatog kao membranski bioreaktorski sustav s izdvojenom membranom (MBR). Kemijski proces obrade otpadne vode obuhvaćao je oksidaciju ozonom. Eksperimenti su provedeni kroz duže vrijeme na poluindustrijskom bioreaktorskom postrojenju. Promatrane su karakteristike rada pilot membranskog bioreaktora s vanjskom membranskom jedinicom uz kontinuirani dotok realne otpadne vode. Karakteristike i rad postrojenja procijenjeni su na osnovi mjerenja karakteristika permeata i promjena vrijednosti parametara kvalitete vode (kemijske potrošnje kisika, KPK, boje, ukupnog dušika, koncentracije nitrita, NO2- i amonijaka, NH4+). Također je pomoću UV-spektrometrije praćena učinkovitost obezbojavanja otpadne vode nakon procesa ozoniranja
Characterization of membrane foulants at ambient temperature anaerobic membrane bioreactor treating low-strength industrial wastewater
Potential of dyes as draw solutions in forward osmosis for the south african textile industry
The textile industry produces large volumes of wastewater that requires appropriate treatment before being released into the environment. Research globally has focused on advanced desalination technologies to augment the limited freshwater resources. Forward osmosis (FO) technology has gained substantial interest as a possible lower-energy desalination technology. However, challenges such as the availability of effective draw solutions (DS) have limited its implementation. This study evaluated alternative feed water resources and assessed the potential of dye solutions as DS. The aim is to dilute a concentrated dye DS to a target concentration for direct dye-batch use, thereby reclaiming water resources. The measured osmotic pressure (OP) of the alternative feed solutions (synthetic brackish water; syntethic seawater; seawater from the Atlantic and Indian Oceans; and wastewater from two textile factories) were 414, 2 761, 2 580, 2 614; 1 716 and 7 822 kPa, respectively. Three basic dyes (Maxilon Turquoise, Red and Blue) and three reactive dyes (Carmine, Olive Green and Black) were selected based on common use in the South African textile industry. The dye samples were prepared without and with lt at different concentrations and different dye-to-salt mass ratios ranging from 1:10 to 1:60. The OP trends for the basic dyes followed Blue >> Red > Turquoise and for the reactive dyes Black >> Olive > Carmine. The overall OP trend was Black > Olive > Carmine > Blue > Red > Turquoise. The OP at different dye concentrations and different dye-to-salt ratios was mostly influenced by the dye chemistry and molecular weight (Mw) rather than the type of dye, i.e., reactive vs basic.The OP trend for the dye-to-salt ratios was 1:60 > 1:50 > 1:40 > 1:30 > 1:20 > 1:10. For both the basic and reactive dyes a linear relationship exists between OP and dye concentration; as well as between OP and Mw. The dye DS exhibited larger OP compared to that of the FS evaluated, thus rendering them suitable DS
Synthesis of Poly-Sodium-Acrylate (PSA)-Coated Magnetic Nanoparticles for Use in Forward Osmosis Draw Solutions
The synthesis of magnetic nanoparticles (MNPs) coated with hydrophilic poly-sodium-acrylate (PSA) ligands was studied to assess PSA-MNP complexes as draw solution (DS) solutes in forward osmosis (FO). For MNP-based DS, the surface modification and the size of the MNPs are two crucial factors to achieve a high osmolality. Superparamagnetic nanoparticles (NP) with functional groups attached may represent the ideal DS where chemical modifications of the NPs can be used in optimizing the DS osmolality and the magnetic properties allows for efficient recovery (DS re-concentration) using an external magnetic field. In this study MNPs with diameters of 4 nm have been prepared by controlled chemical co-precipitation of magnetite phase from aqueous solutions containing suitable salts of Fe2+ and Fe3+ under inert atmosphere and a pure magnetite phase could be verified by X-ray diffraction. Magnetic colloid suspensions containing PSA-coated MNPs with three different molar ratios of PSA:MNP = 1:1, 1:2 and 1:3 were prepared and assessed in terms of osmotic pressure, aggregation propensity and magnetization. Fourier Transform Infrared Spectroscopy (FTIR) confirmed the presence of PSA on coated MNPs and pristine PSA-MNPs with a molar ratio PSA:MNP = 1:1 exhibited an osmotic pressure of 30 bar. Molar ratios of PSA:MNP = 1:2 and 1:3 lead to the formation of less stabile magnetic colloid solutions, which led to the formation of aggregates with larger average hydrodynamic sizes and modest osmotic pressures (5.5 bar and 0.2 bar, respectively). After purification with ultrafiltration, the 1:1 nanoparticles exhibited an osmotic pressure of 9 bar with no aggregation and a sufficient magnetization of 25 emu/g to allow for DS regeneration using an external magnetic field. However, it was observed that the amount of PSA molecules attached to the MNPs decreased during DS recycling steps, leaving only strong chelate-bonded core-shell PSA as coating on the MNPs. This demonstrates the crucial role of MNP coating robustness in designing an efficient MNP-based DS for FO
Comparison of different rootstock for grafting tomatoes (Lycopersicon esculentum Mill.)
Poskus primerjave različnih podlag za cepljenje paradižnika je potekal v neogrevanem plastenjaku Fakultete za kmetijstvo in biosistemske vede na Pohorskem dvoru. Na podlage \u27Maxifort\u27, \u27Vigomax\u27 in \u27Beaufort\u27 smo s cepljenjem v zarezo cepili kultivarja Optima F1\u27 in \u27Saint Pierre\u27. Namen raziskave je bil preveriti ali lahko s cepljenjem povečamo rast in pridelek paradižnika. Uspešnost cepljenja pri podlagi \u27Maxifort\u27 je bila 69 %, pri \u27Vigomax\u27 59 % in pri \u27Beaufort\u27 57 %. Med cepljenimi in necepljenimi rastlinami ni bilo statistično značilnih razlik pri skupnem in tržnem pridelku, niti med morfološkimi lastnostmi. Na paradižniku ni bilo opaženih znakov talnih bolezni, ki bi jih lahko s cepljenjem preprečili, ker na poskusni parceli v preteklih letih ni bilo intenzivne pridelave paradižnika in tla niso okužena. Se pa kažejo trendi večjega pridelka na cepljenih rastlinah.The attempt to compare different rootstock of tomatoes for grafting was done in an unheated plastic container in the Faculty for agriculture and biosystems in Pohorski dvor. With grafting on \u27Maxifort\u27, \u27Vigomax\u27 and \u27Beaufort\u27 rootstock with cultivated \u27Optima F1\u27 and \u27Saint Pierre\u27. The purpose of this research was to verify if we boost the growth and yield with grafting. Success rate of the \u27Maxifort\u27 rootstock was at 69 % , \u27Vigomax\u27 at 59 % and \u27Beaufort\u27 at 57 %. Statistically speaking there were practically no differences between grafted and plants that were not grafted in combined and marketing yield, not even in morphological characteristics. There were no signs of ground diseases which would have been prevented with grafting because there was no heavy tomato production on the test soil in the past years. But there are sings of a bigger yield on grafted plants
The history of puppetry
V diplomskem delu z naslovom Zgodovina lutkarstva smo želeli raziskati lutke in zgodovino lutkarstva. Namen diplomskega dela je bil, da s pomočjo strokovne literature naredimo pregled in izvor zgodovine lutkarstva. Osredotočili smo se tudi na različne vrste lutk in jih opisali. Zanimalo pa nas je tudi lutkarstvo na Slovenskem in pomembni slovenski lutkarji. Diplomsko delo je teoretično in pri pisanju smo uporabili deskriptivno metodo s študijem domače in tuje literature.
Lutka je že od nekdaj okoli nas. Ta starodavna umetnost se pojavi že v pradavnini in je prisotna ter priljubljena še dandanes po vsem svetu. Seveda se je lutka skozi različna časovna obdobja spreminjala, ampak bila prisotna skoraj vsepovsod. V lutkovnih predstavah uživajo ljudje vseh starosti, priljubljena pa je tudi v vrtcih in šolah. Lutkarstvo poznamo kot umetniško gledališko zvrst, vzgojno-terapevtsko sredstvo in kot otroško kreativno igro.
Za začetnika lutkarske dejavnosti v Sloveniji štejemo Milana Klemenčiča, ki je sestavil repertoar Slovenskega marionetnega gledališča in postavil pomembne temelje slovenskega umetniškega lutkarstva.In the thesis entitled The History of Puppetry, we wanted to explore the puppets and the history of puppetry. The purpose of the diploma thesis was to make a review of the origin and the history of puppetry with the help of professional literature. Further, we focused on various types of puppets and their description, as well as, the puppetry in Slovenia and important Slovenian puppeteers. The diploma thesis is theoretical, while writing we used a descriptive method with the study of indigenous and foreign literature.
The puppet has always been around us. This ancient art is present and beloved all around the world even today. Indubitably the puppet changed over time, but it was present almost everywhere. Puppet shows are enjoyed by people of all ages and are popular in kindergartens and schools. Puppetry is known as an artistic theatrical genus, an educational therapeutic agent and as a children\u27s creative game.
Milan Klemenčič is considered the beginner of puppetry in Slovenia when he created the repertoire of the Slovenian Marionette Theatre and laid the foundations of the Slovenian art puppetry