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Hierarchical multilabel classification method with feature extraction based on textual analysis of microbial data
Get PDFZanesljiva identifikacija kompleksnih vsebinskih struktur v primerih, kjer posamezni primerki podatkovnega nabora niso homogeni, pač pa združujejo informacije več virov, predstavlja enega izmed ključnih metodoloških izzivov sodobne podatkovne analitike. Relativno enostavna je namreč naloga, kjer je določen primerek homogen in ga z uporabo večrazredne klasifikacije znamo relativno preprosto razvrstiti v enega izmed ponujenih razredov. Kompleksnost pa se drastično poveča, ko se v istem primerku skriva več virov. V tem primeru osnovne metode analize ne zadostujejo več in potrebujemo naprednejše pristope, ki so sposobni razbrati soobstoj več razredov oziroma oznak, kar je tudi domena večznačne klasifikacije. V predloženi doktorski disertaciji obravnavamo omenjeni problem na področju metagenomike, ki med drugim omogoča raziskovanje mikrobiote, raznolike skupnosti bakterij in drugih mikroorganizmov v določenem okolju. Z naprednimi tehnikami sekvenciranja iz njih pridobimo zaporedja DNK celotne mikrobne združbe, ki jih lahko opišemo kot izjemno dolga besedila, zapisana z abecedo štirih nukleotidov: A, T, G in C. Naš cilj je v teh besedilih poiskati t. i. označevalne gene, ki so izključno ali močno povezani z gostiteljem. V ta namen smo na podlagi optimizacijskih pristopov in domenskih pravil predlagali metodo ekstrakcije značilnic, temelječo na osnovi k-merov, tj. krajših delov DNK. Pristop na osnovi k-merov se je izkazal za zelo učinkovitega, zato smo ga uporabili tudi pri sintetičnem generiranju vzorcev mikrobnih oziroma mikrobiotskih podatkov. Metoda temelji na pripravi profilov k-merov in na nanje osnovanih grafih prehodov. Ker smo v doktorski disertaciji analizirali lokacijsko specifične vzorce, smo morali njihov manjši nabor čistih vzorcev ustrezno razširiti. Še več, sintetično smo razširili tudi nabor mešanih vzorcev, kar predstavlja še večji izziv v realnih okoljih. Obe predlagani metodi sta se združili v konceptualno najzahtevnejšem delu doktorske naloge, predlagani metodi hierarhične večznačne klasifikacije na osnovi ekstrakcije značilnic, imenovani MLB. Z njo smo na osnovi vhodnih podatkov, tj. čistih ali sintetično ustvarjenih vzorcev, napovedovali deleže gostiteljev v mešanih mikrobnih vzorcih. Rezultate metode MLB smo primerjali s tistimi, pridobljenimi z orodjem SourceTracker, vodilnim orodjem za natančno identifikacijo in kvantifikacijo gostiteljev mikrobov v mešanih vzorcih. Metodi smo ovrednotili z uveljavljenimi metrikami na področju večznačne klasifikacije, ki razkrivajo, da metoda MLB učinkovito rešuje problem določitve gostiteljev in njihovih deležev ter poda primerljive, večinoma pa boljše rezultate kot orodje SourceTracker.Reliable identification of complex content structures in cases where individual dataset instances are not homogeneous, but consist of information from multiple sources, represents one of the key methodological challenges in modern data analytics. The task is relatively straightforward when an instance is homogeneous, and can be easily classified into one of the available classes using multiclass classification. However, the complexity increases drastically when multiple sources are present within the same instance. In such cases, basic analytical methods are no longer sufficient, and advanced approaches capable of determining the coexistence of multiple classes or labels are required, which is the domain of multilabel classification. In the presented doctoral dissertation, we address this challenge within the field of metagenomics, which enables the exploration of the microbiome, a diverse community of bacteria and other microorganisms in a given environment. Using advanced sequencing techniques, we obtain DNA sequences of the entire microbial community, which can be described as extremely long texts written with the alphabet of four nucleotides: A, T, G, and C. Our goal is to identify so-called marker genes in these texts that are exclusively or strongly associated with a specific host. Hence, we proposed a feature extraction method based on optimization approaches and domain rules, relying on k-mers, i.e., shorter segments of DNA. The k-mer-based approach proved to be very effective, and we therefore applied it to the synthetic generation of microbial data samples. The method relies on creating k-mer profiles and corresponding transition graphs. Since we analyzed location-specific samples, we needed to expand their smaller set of pure samples accordingly. Furthermore, we synthetically expanded the set of mixed samples, which poses an even greater challenge in real-world settings. Both proposed methods were combined in the conceptually most demanding part of the dissertation: a proposed hierarchical multilabel classification method with feature extraction, named MLB. This method predicts the proportions of hosts in mixed microbial samples based on input data, i.e., pure or synthetically generated samples. The results of the MLB method were compared with those obtained by the SourceTracker, a leading tool for predicting and quantifying microbial hosts in mixed samples. Both methods were evaluated using established metrics, revealing that the MLB method effectively addresses the problem of identifying hosts and their proportions, delivering comparable, and in most cases, superior results to SourceTracker
Magnetic separation of oil spills from water using cobalt ferrite nanoparticles with fluorocarbon functionalization
Get PDFIn the present study, we synthesized fluorocarbon-coated cobalt ferrite (CoFe2O4) magnetic nanoparticles using alkoxysilanes such as trimethoxy(3,3,3-trifluoropropyl)silane (TFPTMS), trimethoxy(1H,1H,2H,2H-nonafluorohexyl)silane (NFHTMS), and triethoxy(1H,1H,2H,2H-perfluorodecyl)silane (PFDTES). The synthesized nanoparticles were characterized by various techniques, including X-ray diffractometry (XRD), transmission electron microscopy (TEM/HRTEM/EDXS), Fourier transform infrared spectroscopy (FTIR), specific surface area measurements (BET), and magnetometry (VSM). To understand their surface characteristics, contact angle (CA) measurements were carried out, providing valuable insights into their hydrophobic properties. Among the samples of CoFe2O4 coated with fluoroalkoxysilanes, those with PFDTES surface coating had the highest water contact angle of 159.2°, indicating their superhydrophobic character. The potential of the prepared fluoroalkoxysilane-coated CoFe2O4 nanoparticles for the removal of waste low-SAPS synthetic engine oil from a model aqueous solution was evaluated based on three key parameters: adsorption efficiency (%), adsorption capacity (mg/g), and desorption efficiency (%). All synthesized CoFe2O4 samples coated with fluoroalkoxysilane showed high oil adsorption efficiency, ranging from 87% to 98%. The average oil adsorption capacity for the samples was as follows: F3-SiO2@CoFe2O4 (3.1 g of oil/g of adsorbent) > F9-SiO2@CoFe2O4 (2.7 g of oil/g of adsorbent) > F17-SiO2@CoFe2O4 (1.5 g of oil/g of adsorbent) as a result of increasing oleophobicity with increasing fluorocarbon chain length. The desorption results, which showed 77–97% oil recovery, highlighted the possibility of reusing the adsorbents in multiple adsorption/desorption cycles
Notaries, chamberlains, and court masters
Get PDFTema članka je primerjava razvoja dvornih služb vladarjev vojvodine Štajerske in grofije Tirolske v 12. in 13. stoletju. Na Štajerskem iz virov razberemo hiter razvoj aparata dvornih služb že globoko v 12. stoletju, za kar je bil zaslužen mejni grof Otokar III., ki je svoji mejni grofiji vladal že med letoma 1129 in 1164. Po drugi strani je bil tovrstni razvoj na Tirolskem mnogo počasnejši, čeprav prve grofovske dvorne uradnike tudi tam srečamo že sredi 12. stoletja. To se je spremenilo v času vlade tirolskega grofa Majnharda II. (sicer tudi koroškega vojvode), ki je na Tirolskem vladal med letoma 1258 in 1295.The article focuses on the development of court offices under the rulers of the Duchy of Styria and the County of Tyrol in the twelfth and thirteenth centuries. In Styria, sources already point to a swift development of the court administration structure in the twelfth century, which was owed to Margrave Ottokar III, who governed his margraviate between 1129 and 1164. On the other hand, such development was much slower in the County of Tyrol, even though the first court officials may also be encountered there as early as the mid-twelfth century. This changed during the period of Count Meinhard II (who was also Duke of Carinthia), who ruled over Tyrol between 1258 and 1295
Psychological factors and price movements in financial markets: an analysis using the fear & greed index
Get PDFMagistrska naloga analizira vpliv psiholoških dejavnikov na gibanje cen na finančnih trgih, pri čemer je osrednji analitični okvir indeks strahu in pohlepa (Fear & Greed Index – FGI). Delo združuje teoretične osnove psihologije odločanja z vedenjsko ekonomijo, pri čemer izpostavlja vlogo čustev kot pomembnega, a pogosto spregledanega dejavnika pri investicijskih odločitvah. Teoretični del obravnava povezavo med čustvi in kognicijo, vedenjske anomalije, kot so učinek lastništva, pristranskost statusa quo in strah pred izgubo, ter psihologijo naložbenega procesa. Empirični del temelji na statistični analizi povezave med indeksom strahu in pohlepa ter vrednostmi glavnih ameriških borznih indeksov (S&P 500, Dow Jones, Nasdaq, NYSE Composite) in ceno kriptovalute Bitcoin. Uporabljene so metode deskriptivne statistike, Spearmanove korelacije ter neparametrični testi (Kruskal-Wallis, Dunn-Bonferroni). Rezultati potrjujejo obstoj statistično značilne povezave med indeksom strahu in pohlepa in gibanjem delniških indeksov ter razlike v povprečni ceni Bitcoina med različnimi obdobji razpoloženja na trgu (strah, nevtralnost, pohlep). Naloga ugotavlja, da so razpoloženje vlagateljev in širše čustveno stanje na trgu pomembna napovednika kratkoročnih tržnih gibanj. Ugotovitve prispevajo k boljšemu razumevanju psiholoških vplivov na finančne trge ter predstavljajo podlago za oblikovanje učinkovitejših strategij upravljanja tveganj in naložbenega odločanja.The master\u27s thesis analyzes the impact of psychological factors on price movements in financial markets, with the Fear & Greed Index (FGI) serving as the central analytical framework. The study combines theoretical foundations from decision psychology and behavioral economics, emphasizing the role of emotions as a significant yet often overlooked factor in investment decision-making. The theoretical part explores the connection between emotions and cognition, behavioral anomalies such as the endowment effect, status quo bias, and loss aversion, as well as the psychology of the investment process. The empirical part is based on statistical analysis of the relationship between the Fear & Greed Index and the values of major U.S. stock indices (S&P 500, Dow Jones, Nasdaq, NYSE Composite) and the price of Bitcoin. Methods employed include descriptive statistics, Spearman’s rank correlation, and non-parametric tests (Kruskal-Wallis, Dunn-Bonferroni). The results confirm a statistically significant relationship between the Fear & Greed Index and stock market movements, as well as differences in the average price of Bitcoin across various market sentiment periods (fear, neutrality, greed). The thesis concludes that investor sentiment and the broader emotional climate of the market are important predictors of short-term market dynamics. The findings contribute to a deeper understanding of psychological influences on financial markets and offer a foundation for developing more effective trading strategies and risk management approaches
The impact of corporate intelligence on the competitive advantage in the business world
Get PDFKorporativna obveščevalna dejavnost je vrsta poslovne dejavnosti, ki se izvaja v gospodarski sferi. Njen namen se uresničuje skozi pridobivanje podatkov, ki predstavljajo podporo pri strateškem odločanju in posledično pri ustvarjanju konkurenčne prednosti na poslovnem trgu. V magistrskem delu je bilo ugotovljeno, da ima ta dejavnost zelo pomembno vlogo pri poslovanju podjetij, predvsem na globalni ravni. Ugotovljeno je bilo, da je postala celo nepogrešljivo orodje za uspešno pozicioniranje podjetij in bo v prihodnosti imela še večjo vlogo in pomen, delno tudi zaradi tehnoloških sprememb znotraj le te. Magistrsko delo se osredotoča tudi na resnično izvajanje dejavnosti v slovenskih podjetjih in njen vpliv na poslovno uspešnost. Pri tem je bilo ugotovljeno, da se pri izvajanju dejavnosti uporabljajo številne programske opreme, ki v veliki meri olajšajo izvajanje, hkrati pa povečujejo potrebo po ustrezno usposobljenem kadru. V magistrskem delu so identificirane prednosti in slabosti, ki se pojavljajo pri praktičnem izvajanju omenjene dejavnosti, hkrati pa tudi izzivi in omejitve, na katere naleti dotični kader. Ugotovitve imajo podlago v intervjujih s posamezniki, ki se v slovenskih podjetjih ukvarjajo z danim področjem. Intervjuvanci prepoznavajo to dejavnost kot pomembno orodje za spremljanje konkurenčnega okolja in pridobivanje relevantnih podatkov za sprejemanje boljših poslovnih odločitev. Korporativna obveščevalna dejavnost je v primerjavi z globalnim trgom, v Republiki Sloveniji še vedno v povojih, vendar se stvari v zadnjih letih spreminjajo. Zaradi pomena, ki ga ima omenjena dejavnost za ustvarjanje konkurenčne prednosti in potenciala, ki ga lahko doseže v prihodnosti, je o njej smiselno govoriti, vsaka raziskava pa odpira številna nova področja in možnosti za nadaljnje raziskovanje.Corporate intelligence is a type of business activity carried out in the economic sphere. Its purpose is pursued through the acquisition of information that supports strategic decision-making and, consequently, the creation of competitive advantage in the business market. The master thesis concluded that this activity plays a very important role in the business of companies themselves, especially at a global level. It was found that it has even become an indispensable tool for the successful positioning of companies and will play an even greater role and importance in the future, partly due to the technological changes within the business. The master thesis also focuses on the actual implementation of the activity in Slovenian companies and its impact on business performance. It is found that a number of software applications are used in the implementation of activities, which greatly facilitate the implementation, while at the same time increasing the need for appropriately qualified staff. The Master\u27s thesis also identifies the advantages and disadvantages that arise in the practical implementation of the activity, as well as the challenges and constraints encountered by the personnel concerned. The findings are based on interviews with individuals working in the field in Slovenian companies. The interviewees identify this activity as an important tool to monitor the competitive environment and to obtain relevant information to make better business decisions. Corporate intelligence is still in its infancy in the Republic of Slovenia compared to the global market, but things have been changing over the years. The importance of this activity for creating competitive advantage and the potential it has for the future make it worth talking about, and each study opens up many new areas and possibilities for further research
Cloud-Based ERP solutions: a case study of small businesses
Get PDFV diplomski nalogi smo obravnavali oblačne rešitve ERP na primeru dveh rešitev – Microsoft Dynamics 365 Business Central in Odoo – z vidika njihove uporabe v malih slovenskih podjetjih. Rešitve ERP omogočajo povezovanje poslovnih funkcij v enoten sistem, oblačne različice pa prinašajo dodatne prednosti, kot so nižji stroški, hitrejša uvedba, enostavno vzdrževanje in dostopnost kjerkoli in kadarkoli.
V teoretičnem delu smo predstavili značilnosti računalništva v oblaku in rešitev ERP, v empiričnem pa primerjalno analizirali Odoo in Business Central glede funkcionalnosti, arhitekture, možnosti integracije ter primernosti za mala podjetja. Ugotovili smo, da je Business Central posebej primeren za podjetja, ki že delujejo znotraj Microsoftovega ekosistema, medtem ko Odoo izstopa po svoji prilagodljivosti, odprtokodnosti in modularnem pristopu.
Študiji primera podjetij IC Elektronika in Valens potrjujeta, da ERP v oblaku pomembno prispeva k večji preglednosti, avtomatizaciji ter splošni učinkovitosti poslovanja. Obe rešitvi sta primerni za mala podjetja, končna izbira pa je odvisna od specifičnih poslovnih potreb, proračuna ter razpoložljivih tehničnih znanj v podjetju.In our thesis, we examined cloud-based ERP solutions using two examples—Microsoft Dynamics 365 Business Central and Odoo—from the perspective of their use in small Slovenian companies. ERP solutions enable the integration of business functions into a single system, while cloud versions offer additional advantages such as lower costs, faster implementation, easy maintenance, and accessibility anywhere and anytime.
In the theoretical part, we presented the characteristics of cloud computing and ERP solutions, while in the empirical part, we conducted a comparative analysis of Odoo and Business Central in terms of functionality, architecture, integration options, and suitability for small businesses. We found that Business Central is particularly suitable for companies that already operate within the Microsoft ecosystem, while Odoo stands out for its flexibility, open source nature, and modular approach.
Case studies of IC Elektronika and Valens confirm that cloud-based ERP significantly contributes to greater transparency, automation, and overall business efficiency. Both solutions are suitable for small businesses, but the final choice depends on specific business needs, budget, and the technical expertise available within the company
Digitalization in accounting on the example of the Kovintrade d. d. company
Get PDFDiplomsko delo obravnava vpliv digitalizacije na področju računovodstva, s praktičnim primerom podjetja Kovintrade d.d. V teoretičnem delu so predstavljeni osnovni pojmi digitalizacije, razvoj, ter njihov vpliv na računovodske procese. Poseben poudarek je namenjen brezpapirnem poslovanju, kjer je opisan pomen eRačuna. Pozornost je namenjena tudi novodobnemu izzivu digitalnega delovnega okolja kot je pravica do odklopa, ki digitalizacija prinaša zaposlenim. Izpostavljeno je, da uspešna digitalizacija zahteva ne le tehnološke spremembe, temveč tudi nadgradnjo znanja in veščin zaposlenih, predvsem na področju digitalnih kompetenc, ki omogočajo učinkovito uporabo sodobnih orodij ter prilagajanje novim načinom. V empiričnem delu predstavimo podjetje Kovintrade d.d. Celje, kjer je poudarek na uvedbi sodobne platforme.The thesis deals with the impact of digitalization in the field of accounting, with the practical example of Kovintrade d.d. The theoretical part presents the basic concepts of digitalization, its development, and its impact on accounting processes. Special emphasis is given to paperless business, where the importance of eInvoicing is described. Attention is also paid to the modern challenge of the digital workplace, such as the right to disconnect that digitisation brings to employees. It is pointed out that successful digitisation requires not only technological change, but also upgrading employees\u27 knowledge and skills, especially in the area of digital competences, which enable them to use modern tools effectively and to adapt to new ways of doing things. In the empirical part we present the company Kovintrade d.d. Celje, where the focus is on the introduction of a modern platform
Analysis of an electromagnetic levitation system based on the TEAM workshop problem 28
Get PDFCilj magistrske naloge je izdelava in preizkus sistema magnetne levitacije, ki sestoji iz dveh zaporedno vezanih tuljav in aluminijastega diska. Gre za sistem elektrodinamične levitacije oziroma suspenzije prevodnih materialov, ki magnetno levitacijo dosežejo iz magnetnega polja, ki je posledica inducirane napetosti in vrtinčnih tokov v prevodnem materialu. Obravnavana je izdelava in rezultati simulacijskega izračuna v programskem orodju Altair Flux, ki je namenjeno numeričnemu izračunu magnetnih kot tudi drugih polj. Izdelan je fizični model sistema magnetne levitacije v laboratoriju, kjer je sistem bil preizkušen in merjen. Izvedena je primerjava rezultatov, pridobljenih iz simulacijskega izračuna in fizičnega preizkusa v laboratoriju, z referenčnimi rezultati, ki so jih podali avtorji naloge. Rezultati simulacijskega izračuna in laboratorijske meritve so podani kot časovni poteki premikanja aluminijastega diska in se ujemajo z referenčnimi rezultati avtorjev navodil. Opazna so pričakovana odstopanja med rezultati simulacijskega izračuna, laboratorijske meritve in referenčnih rezultatov, ki so posledica načina izdelave simulacijskega modela in modela v laboratorijskem preizkusu.The master\u27s thesis aims to create and test a magnetic levitation system consisting of two coils connected in series and an aluminium disk. It is a system of electrodynamic levitation or suspension of conductive materials that achieves magnetic levitation from the magnetic field resulting from the induced voltage and eddy currents in the aluminium disk. The creation and results of the simulation in the Altair Flux software tool, which is intended for the numerical calculation of magnetic as well as other fields, are discussed. A physical model of the magnetic levitation system was created in the laboratory, where the system was tested and measured. A comparison of the results obtained from the simulation calculation and physical testing in the laboratory was performed with the reference results provided by the authors of the instructions. The results of the simulation calculation and laboratory measurement are given as time courses of the movement of the aluminium disk and match the reference results of the authors of the instructions. Expected deviations between the results of the simulation calculation, laboratory measurement and reference results are noticeable, which are a consequence of the way the simulation model and the model in the laboratory test are build
Toward precision medicine
Get PDFUlcerative colitis (UC), a subtype of inflammatory bowel disease (IBD), is a chronic, relapsing inflammatory condition that significantly impairs the patient’s quality of life. While biologics have transformed disease management, a substantial number of patients remain unresponsive or lose efficacy over time. Tofacitinib (TOFA), an oral Janus kinase (JAK) inhibitor, introduces a novel therapeutic class of small-molecule drugs with a unique oral administration route, offering enhanced patient convenience and broader accessibility compared to parenterally administered biologics. As the first oral treatment approved for moderate to severe UC in years, TOFA acts by modulating the JAK/STAT pathway, influencing critical inflammatory mediators such as IL-6, IL-17, and IFN-γ. However, response rates are variable and appear dose-dependent, with up to 60% of patients showing inadequate therapeutic outcomes. This review represents the first comprehensive synthesis focused specifically on biomarkers of TOFA response in UC. Drawing on multi-omics data—epigenomics, transcriptomics, proteomics, and cellular profiling, we highlight emerging predictors of responsiveness, including CpG methylation signatures (e.g., LRPAP1 and FGFR2), transcriptomic regulators (e.g., REG3A and CLDN3), immune and epithelial cell shifts, and the cationic transporter MATE1. TOFA demonstrates a dual mechanism by modulating immune responses while supporting epithelial barrier restoration. Despite being promising, TOFA’s dose-dependent efficacy and interpatient variability underscore the critical need for non-invasive, predictive biomarkers to guide personalized treatment. As the first review of its kind, this work establishes a basis for precision medicine approaches to optimize the clinical utility of TOFA in UC management
Online gambling regulatory policy: an analysis from the perspective of the rights and duties of the gambler in Portugal
Get PDFOnline games constitute an increasingly widespread activity that carries increased risks for players, especially minors. This study analyses the effectiveness of protecting online players\u27 rights considering Portuguese legislation, which originates from the common European rules established for all Member States of the European Union. This study aims to characterise the Portuguese regulatory policy for games of chance, especially in the online gaming modality, its regulatory principles, its characteristics, and purposes, and to describe how it articulates with European recommendations. Based on this characterisation, this study analyses the effectiveness of compliance with the fundamental aspects of this regulatory policy by entities operating online gambling from the perspective of protecting the rights and duties of players, as enshrined. It concludes that some of these rights need to be sufficiently protected. The methodology includes analysing the websites of licensed entities and providing a questionnaire to young people who frequently play online. The study shows that the information on online gaming platforms reasonably complies with the current legal requirements and that players must be fully aware of all their rights. It also highlights that such rights are not fully protected in sensitive aspects.Spletne igre so vse bolj razširjena dejavnost, ki prinaša večja tveganja za igralce, zlasti mladoletnike. Ta študija analizira učinkovitost zaščite pravic spletnih igralcev ob upoštevanju portugalske zakonodaje, ki izhaja iz skupnih evropskih pravil, določenih za vse države članice Evropske unije. Namen te študije je opisati portugalsko regulativno politiko za igre na srečo, zlasti na področju spletnih iger na srečo, njena regulativna načela, značilnosti in namene ter opisati, kako se ujema z evropskimi priporočili. Na podlagi te opredelitve ta študija analizira učinkovitost upoštevanja temeljnih vidikov te regulativne politike s strani subjektov, ki prirejajo spletne igre na srečo, in z vidika varstva pravic in dolžnosti igralcev. Ugotavlja, da je treba nekatere od teh pravic zaščititi v zadostni meri. Metodologija vključuje analizo spletnih strani licenciranih subjektov in posredovanje vprašalnika mladim, ki pogosto igrajo na spletu. Študija kaže, da so informacije na spletnih igralnih platformah v razumni meri skladne z veljavnimi zakonskimi zahtevami in da se morajo igralci v celoti zavedati vseh svojih pravic. Poudarja tudi, da te pravice v občutljivih vidikih niso v celoti zaščitene