Modernization of the underfloor copying wheel lathe for reprofiling of railroad wheelsets

V podjetju SŽ – Vleka in tehnika, d. o. o., Center Ljubljana, se ukvarjajo z vzdrževanjem vseh vrst železniških vozil, vleko vlakov in tehničnimi vagonskimi dejavnostmi. Vzdrževalna dela, opravljena na voznih površinah kolesnih dvojic različnih vrst železniških vozil, se izvajajo z uporabo podnivojske kopirne stružnice proizvajalca Hegenscheidt-MFD, tipa stroja 105 z letom izdelave 1979. Modernizacija obdelovalnega stroja bi izboljšala konkurenčnost z drugimi tujimi vzdrževalnimi podjetji na trgu. V magistrskem delu so za boljše razumevanje predstavljene tematike najprej opredeljene osnove na področju obdelave in vzdrževanja tekalnih profilov in sledilnih vencev kolesnih dvojic na tirnih vozilih. Nato je v prvem sklopu zaključnega dela analizirana podnivojska kopirna stružnica, uporabljena v obravnavanem podjetju. To vključuje opis sestavnih komponent, določitev tehničnih specifikacij stroja, predstavitev načina delovanja stroja, opredelitev poglavitnih pomanjkljivosti stroja ter navedbo vzrokov za neuspelo posodobitev in lastnosti izvedljive modernizacije obdelovalnega stroja. V drugem sklopu zaključnega dela je za obravnavano podjetje po izpolnitvi različnih pomembnih kriterijev in z najboljšimi tehničnimi specifikacijami izbran vodilni model podnivojske CNC-stružnice na trgu. V zaključku so primerjane tehnične specifikacije in način delovanja uporabljene podnivojske kopirne stružnice z izvedeno možno posodobitvijo in predlaganim novim modelom podnivojske CNC-stružnice. Na osnovi vseh pridobljenih podatkov je obravnavanemu podjetju predlagan najboljši potek ukrepanja na področju strategije konkurenčnosti vzdrževanja tirnih vozil.In the company SŽ - Vleka in tehnika d.o.o., Center Ljubljana, they deal with an array of railway services ranging from train traction and maintenance of the rolling stock to technical wagon activity. The maintenance work performed on the running surfaces of the wheel sets of various types of railway vehicles is carried out using an underfloor copying wheel lathe of the manufacturer Hegenscheidt-MFD, machine type 105, made in 1979. The desire to modernize the processing machine would improve competitiveness with other foreign maintenance companies present on the market. For a better understanding of the represented topics, the basics in the field of processing and maintenance of profiles and flanges of the wheel sets on rail vehicles are first described in the master\u27s thesis. And then, in the first part of the master\u27s thesis, the company\u27s underfloor copying wheel lathe is analyzed. It includes a description of the components, a determination of the technical specifications, the way the machine works, a definition of the main shortcomings, causes of the desired failed modernization and the characteristics of feasible modernization of the machine tool. In the second part of the final work, after fulfilling various important criteria and with the best technical specifications, the leading model of the underfloor wheel CNC lathe currently present on the market was selected for the company SŽ - Vleka in tehnika d.o.o., Center Ljubljana. In conclusion, the technical specifications and operation procedure are compared of the used underfloor copying wheel lathe with a possible modernization and a proposed new model of underfloor wheel CNC lathe. On the basis of all the obtained data, the best course of action is proposed to the company SŽ - Vleka in tehnika d.o.o., Center Ljubljana in the field of the strategy of competitiveness of rolling stock maintenance

The relationship between self-esteem and friendship among elementary school students

Pozitivno sprejemanje samega sebe je ključno za obvladanje vsakodnevnih izzivov in negovanje zdravih odnosov, medtem ko prijateljstva zagotavljajo ključno podporo, sprejemanje in občutek pripadnosti. V magistrskem delu smo raziskovali povezavo med samopodobo in prijateljstvom pri osnovnošolcih. Zanimalo nas je, kakšna je povezava med samopodobo in številom prijateljev, kako se samopodoba spreminja glede na starost in glede na priljubljenost. V teoretičnem delu smo naredili pregled ugotovitev o mladostništvu, samopodobi in prijateljstvu, v empiričnem delu pa smo s kvantitativno metodologijo preučili povezavo med skupno samopodobo in številom vzajemnih prijatelstjev ter raziskali morebitne razlike med različnimi starostnimi skupinami. V raziskavi je sodelovalo 187 učencev petih in osmih razredov. Ugotovili smo, da obstaja kompleksna povezava med skupno samopodobo, številom vzajemnih prijateljstev in priljubljenostjo pri učencih. Učenci s pozitivnejšo skupno samopodobo imajo običajno več prijateljev, vendar skupna samopodoba z napredovanjem v višje razrede postaja bolj negativna. Število vzajemnih prijateljstev ostaja relativno stabilno glede na starost. Zaznana priljubljenost, tako s strani sošolcev kot posameznika samega, je povezana s pozitivnejšo skupno samopodobo, medtem ko je podcenjevanje lastne priljubljenosti IV negativno povezano s skupno samopodobo. Rezultati podpirajo pomen razvoja zdrave samopodobe in pozitivnih odnosov med vrstniki.Positive self-acceptance is crucial for managing daily challenges and fostering healthy relationships, while friendships provide essential support, acceptance, and a sense of belonging. In this master\u27s thesis, we investigated the connection between self-esteem and friendship among elementary school students. We were interested in the relationship between self-esteem and the number of friends, how self-esteem changes with age, and how it is influenced by perceived popularity. In the theoretical part, we focused on reviewing findings about adolescence, self-esteem, and friendship. In the empirical part, we used a quantitative methodology to examine the connection between overall self-esteem and the number of mutual friendships, while also investigating potential differences between different age groups. The study involved 187 fifth and eighth-grade students. We found that there is a complex relationship between overall self-esteem, the number of mutual friendships, and popularity among students. Students with more positive overall self-esteem tend to have more friends, but overall self-esteem tends to become less positive with progression to higher grades. The number of mutual friendships remains relatively stable with increasing age. Perceived popularity, both by peers and individuals themselves, is associated with more positive overall self-esteem, while underestimating one\u27s own popularity is negatively associated with overall self-esteem. These results support the importance of developing healthy self-esteem and positive relationships with peers

History of the Cerknica Primary School from 1873 to 1987

Začetki šolanja v Cerknici segajo v začetek 19. stoletja. Šola se je v Cerknici zgradila leta 1827 in se je nenehno širila. Leta 1863 je postala dvorazredna, leta 1878 trirazredna, 1879 pa štirirazredna. Za časa Avstro-Ogrske in stare Jugoslavije je na šoli delovala tudi nižja gimnazija, ki je predstavljala višje razrede. Ta je bila v šolskem letu 1958/59 ukinjena, njeni razredi pa so bili pripojeni osnovni šoli, ki je postala 8-letka. Šola je prešla čez več obdobij, večjo je bilo obdobje Marije Terezije in Franca Jožefa II. To je bil čas Avstro-Ogrske, kjer je bilo značilno, da je imela cerkev velik vpliv na šolo, učenci so se morali redno udeleževati svetih maš in večkrat obeležiti cerkvene praznike. V tem obdobju se je tudi intenzivno praznovalo rojstne dneve in godove vladarjev ter cesarjev. Vse skupaj se je spremenilo, ko je šola prišla pod jugoslovansko oblast. Pouk in praznovanje praznikov sta se bistveno spremenila, spremenili pa so se tudi metode in načini poučevanja, ki so postali naprednejši. Skozi čas se je šolsko poslopje nenehno nadgrajevalo. Kljub temu se je šola skozi celotno obdobje srečevala s prostorsko stisko in z različnimi nevšečnostmi, 23. novembra 1943 pa je bila celo v celoti požgano. Šolanje se je za kratek čas preselilo v Dolenjo vas, nato pa se je začela obnova požgane šole. V šolskem letu 1962/63 se je začela graditi nova šola v Cerknici, ki je bila zgrajena v obdobju od leta 1963 do leta 1976. Nova šola je omogočila kvalitetnejšo izvedbo pouka, seveda modernejšo obliko pa poznamo še danes.Schooling in Cerknica began in the early 19th century, with a school built in 1827 and expanding steadily. By 1863, it offered two-year programmes, followed by three-year programmes in 1878 and four-year programmes in 1879. Under the Austro-Hungarian Empire and later the Kingdom of Yugoslavia, it also offered a lower grammar school programme, until the programme was absorbed by a new eight-year primary school programme in the school year 1958/59. The school weathered several historical periods, significantly the reign of Maria Theresa and Franz Joseph II. Their Austro-Hungarian Empire was characterised by the Church\u27s influence on schooling. Pupils had to regularly attend mass and celebrate religious holidays. Birthdays and name-days of rulers and monarchs were intensely celebrated. Everything changed under the Yugoslav authority. The lessons and holiday celebrations changed considerably, as did the teaching, which became more progressive. The school building saw constant enhancements, yet faced spatial constraints and numerous inconveniences, and completely burnt down on 23 November 1943. The schooling temporarily moved to Dolenja vas. The reconstruction of the Cerknica school lasted from 1963 to 1976. The new building enabled enhanced lesson delivery and formed the essence of the school we know today, albeit with modern additions

Chromatographic methods for the determination of lipid peroxidation biomarkers from physiological samples

V magistrskem delu smo razvili in validirali kromatografske metode za določanje biomarkerjev lipidne peroksidacije v fizioloških vzorcih, s poudarkom na malondialdehidu (MDA), ki je ključni kazalec oksidativnega stresa. Uporabili smo tehnike plinske kromatografije z masno spektrometrijo (GC-MS) in tekočinske kromatografije z masno spektrometrijo (LC-MS/MS), ki omogočajo visoko občutljivost in selektivnost pri analizi kompleksnih bioloških vzorcev, kot je serum. Validacija metod je vključevala oceno linearnosti, ponovljivosti, točnosti in mej zaznave (LOD) za MDA in sorodne spojine. Poleg tega smo izvajali teste antioksidativne kapacitete, kot so DPPH, FRAP, CUPRAC, ORAC in TAC, da bi ocenili sposobnost seruma in drugih vzorcev pri nevtralizaciji prostih radikalov. Rezultati kažejo, da so razvite metode natančne, občutljive in primerne za analizo MDA v fizioloških vzorcih. Ugotovili smo, da koncentracije MDA korelirajo z intenzivnostjo oksidativnega stresa, kar potrjuje uporabnost teh biomarkerjev pri spremljanju patoloških stanj. Poleg tega smo pokazali, da ima serum pomembno antioksidativno kapaciteto, ki jo je mogoče učinkovito ovrednotiti z uporabo kombinacije različnih testov. Magistrsko delo prispeva k razvoju naprednih analitskih orodij za raziskave oksidativnega stresa, ki so ključnega pomena za razumevanje vpliva lipidne peroksidacije na zdravje in bolezni ter za razvoj novih terapevtskih strategij.In this master\u27s thesis, we developed and validated chromatographic methods for the determination of lipid peroxidation biomarkers in physiological samples, focusing on malondialdehyde (MDA), a key indicator of oxidative stress. We employed gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques, which provide high sensitivity and selectivity for analyzing complex biological samples, such as serum. The method validation included the assessment of linearity, repeatability, accuracy, and limits of detection (LOD) for MDA and related compounds. Additionally, we performed antioxidant capacity tests, including DPPH, FRAP, CUPRAC, ORAC, and TAC, to evaluate the ability of serum and other samples to neutralize free radicals. The results demonstrate that the developed methods are precise, sensitive, and suitable for MDA analysis in physiological samples. We found that MDA concentrations correlate with oxidative stress levels, confirming the utility of these biomarkers in monitoring pathological conditions. Furthermore, we showed that serum exhibits significant antioxidant capacity, which can be effectively evaluated using a combination of different assays. This master\u27s thesis contributes to the development of advanced analytical tools for oxidative stress research, which are essential for understanding the impact of lipid peroxidation on health and disease and for advancing new therapeutic strategies

Processed food intake assortativity in the personal networks of older adults

Existing research indicates that dietary habits spread through social networks, yet the impact on populations in Eastern Europe, particularly in rural areas, is less understood. We examine the influence of personal networks on the consumption of high-salt processed foods among individuals in rural Romania, with a specific focus on older adults. Using a personal network analysis, we analyze data from 83 participants of varying ages and their social contacts through multi-level regression models. The inclusion of participants across a wider age range allows us to capture the broader dynamics of social networks, reflecting the intergenerational nature of rural communities. Our findings reveal assortativity in dietary habits, indicating that individuals cluster with others who share similar food consumption patterns. Our results underscore the need for public health interventions that account for the influence of social networks on dietary behavior, as addressing high salt intake and its associated health risks may require considering the broader social context beyond older adults. The study contributes to understanding the social determinants of dietary behaviors and highlights the role of personal networks in shaping food choices in vulnerable populations

Organisations\u27 owners as ambassadors of sustainability: searching for synergies between formal higher education woth micro-credentials and the economy to increase sustainability

Trajnostno upravljanje in vodenje organizacij postaja vedno bolj pomembno za dolgoročno uspešnost organizacij, pri tem pa imajo pomembno vlogo lastniki kot upravljalci in oblikovalci politike podjetja. Magistrsko delo obravnava vlogo lastnikov organizacij kot ambasadorjev trajnostnosti in preučuje sinergije med formalnim visokošolskim izobraževanjem, mikrodokazili, razvojem gospodarstva in podjetji za povečanje trajnostnosti. Predstavljeni so ključni koncepti trajnostnosti, integralnega managementa in vpliva lastnikov kot upravljalcev na organizacijo in njene trajnostne usmeritve. Predstavljeni so zakonodajni okviri, standardi, protokoli in druge komponente poročanja organizaciji o trajnostnosti ter povezava tega s pomenom izobraževanja o trajnostnosti za organizacije. V empiričnem delu sta izvedeni dve študiji primera, prva se nanaša na analizo izbranih izobraževanj o trajnostnosti v poslovanju v Sloveniji, druga pa na preučitev izbranih tujih visokošolskih študijskih programov s področja trajnostnosti. Na podlagi ugotovitev je oblikovan predlog modela kurikuluma za trajnostno izobraževanje lastnikov organizacij z uporabo mikrodokazil v visokem šolstvu. Raziskava je pokazala, da je izobraževanje na področju trajnostnosti v poslovanju pomembno, vendar v Sloveniji še ni sistematično urejeno. Zato se mikrodokazila izkazujejo kot potencialno učinkovito orodje za povezovanje akademskega sveta in gospodarstva, kar bi lahko omogočalo boljši prenos znanja ter večjo izobraženost o trajnostnosti v poslovanju.Sustainable governance and management of organizations are becoming increasingly important for the long-term success of businesses, with owners playing a crucial role as governors and as decision-makers of business policy. This master’s thesis examines the role of business owners as sustainability ambassadors and explores the synergies between formal higher education, micro-credentials, the economy development and business sector in enhancing sustainability. Key concepts of sustainability, integral management, and the influence of owners as governors on organization and its sustainability orientations are presented. The thesis also outlines legislative frameworks, standards, protocols, and other reporting components related to organizations\u27 sustainability, emphasizing the importance of sustainability education for businesses. The empirical section includes two case studies. The first case study analyzes selected education programs on sustainability in business in Slovenia, while the second case study examines selected international higher education programs focused on sustainability. Based on the findings, a proposed curriculum model for sustainability education for business owners is developed, proposing incorporating micro-credentials in higher education. The results indicate that sustainability education in business is essential but remains unsystematically structured in Slovenia. Consequently, micro-credentials emerge as a potentially effective tool for bridging academia and the business sector, enabling better knowledge transfer and greater awareness of sustainability in business practices

Modernization of the self-consumption system in energy facilities of 110 kV voltage level

Lastna raba je ključnega pomena za zagotavljanje stabilnosti delovanja energetskega objekta. Vsak energetski objekt ima svoje specifične sisteme lastne rabe glede na vir napajanja. Sistem lastne rabe mora biti načrtovan tako, da ne vpliva na nihanja v energetskem sistemu. Vira napajanja, tako glavni kot pomožni, morata biti načrtovana tako, da zagotavljata zanesljivo delovanje.Self-use is crucial for ensuring stability in the workings of any electric object. Every electric object has its own specific system of self-use that is based on its power source. The system of self-use must be planned in such a way, that it does not interfere with the fluctuations in the energy system. Power sources, both main and auxiliary, must be planned in such a way that they can ensure reliable operations

Comparison between 1d and 3d cfd numerical simulation of excavator underhood

Namen zaključnega dela je primerjava med 1D in 3D CFD numerično simulacijo kompleksnega motornega prostora delovnega stroja. Zanima nas, ali je 1D CFD simulacija smiselna in dovolj natančna za nadaljni razvoj hladilnega sistema. CAD model delovnega stroja je bil uvožen v GEM3D ter primerno obdelan za izvoz v 1D model. 1D model je bil izdelan in simuliran v programski opremi GT-SUITE. Končna ugotovitev je, da trenutno GT-SUITE še ne premore obdelovati tako kompleksnih modelov, vendar ima zelo dobro podlago za obdelavo modelov v začetni fazi razvoja modela.The purpose of this thesis is to compare 1D CFD and 3D CFD numerical simulations of a complex excavator underhood. Question was, whether a 1D CFD simulation is meaningful and accurate enough for the further development of the cooling system. The CAD model of the working machine was imported into GEM3D and appropriately processed for export to a 1D model. 1D model was build and simulated with GT-SUITE software. The final conclusion was that, at the moment, GT-SUITE is not capable of handling such complex 1D models, but it provides a very good foundation for processing models in the initial stages of model development

Recognition of plants and their diseases with mobile application

Raziskava obravnava prepoznavanje izbranih rastlin in njihovih bolezni s pomočjo mobilne aplikacije. Na kratko so predstavljena uporabljena orodja: Orange Data mining, Android Studio, MS Visio, Figma, Flask, Nginx in Gunicorn. Arhitektura rešitve obsega virtualno okolje v oblaku s strežniki za dostop do modelov za klasifikacijo rastlin in njihovih bolezni in aplikacijo Android. Opisan je postopek izdelave modelov strojnega učenja, ki so bili preneseni na strežnik. V nalogi so prikazani pomembni deli kode in podana razlaga vseh aspektov delovanja aplikacije.The research focuses on recognizing selected plants and their diseases through a mobile application. Key tools Orange Data Mining, Android Studio, Figma, Flask, Nginx, and Gunicorn are briefly introduced. The solution\u27s architecture consists of a cloud based virtual environment hosting servers that run models to classify plants and their diseases, along with an Android application. The process of developing machine learning models and deploying them to the server is detailed, with essential code snippets and explanations of all aspects of the application\u27s functionality provided in the assignment

Motivating Employees to Undergo Further Training Within the Company X

V diplomskem delu smo obravnavali in raziskovali motivacijo za izobraževanje zaposlenih v podjetju X, ki je eden največjih trgovcev z urami in modnim nakitom v regiji. Ker podjetje X deluje v panogi, kjer se povpraševanje in ponudba dnevno spreminjata ter je obenem konkurenca zelo močna, je treba zaposlene ustrezno izobraževati za doseganje boljših poslovnih rezultatov. Namen diplomskega dela je bil ugotoviti, kaj najbolj motivira ali ovira zaposlene pri izobraževanju ter na katerih področjih in kdaj bi si želeli izobraževanja. Za željo po dodatnem izobraževanju sta pri posamezniku ključna spodbudna motivacija in jasen razlog za udeležbo. Diplomsko delo zajema teoretično opredelitev motivacije, izobraževanja in obstoječih motivacijskih teorij. V nadaljevanju sledijo predstavitev podjetja X ter izvedba raziskave in diskusija rezultatov. V teoretičnem delu smo uporabili deskriptivno metodo in metodo kompilacije, medtem ko smo v empiričnem delu s pomočjo anketnega vprašalnika proučevali stanje v podjetju X. Pridobljene rezultate smo nato prikazali v tabelah in grafih z uporabo različnih statističnih metod. Ob koncu diplomskega dela smo odgovorili na raziskovalna vprašanja. Ugotovili smo, da zaposlene za dodatno izobraževanje najbolj motivirata osebno zadovoljstvo in prispevek k lastnemu razvoju. Največjo oviro predstavlja preobremenjenost. Zaposleni bi si želeli pridobiti največ znanja na področju tujih jezikov in komunikacijskih veščin. Najraje bi se izobraževali v službenem času, v obliki praktičnih delavnic, predavanj in skupinskih izobraževanj. Podatki bodo podjetju X v pomoč pri odločitvi, na katera izobraževanja naj se osredotoči in kdaj naj jih začne izvajati. Prav tako bomo pridobili informacije o tem, katera področja in oblike zaposleni najbolj potrebujejo.In this diploma thesis, we discussed and researched the motivation for educating employees of Company X, one of the largest retailers of watches and fashion jewelry in the region. Since Company X operates in an industry where demand and supply change daily, and competition is very strong, it is necessary to properly educate employees to achieve better business results. The purpose of the diploma thesis was to identify what most motivates or hinders employees in pursuing education, as well as to determine in which areas and when they would like to receive training. An individual\u27s desire for additional education is key to stimulating motivation and provides a clear reason for participation. This diploma thesis covers the theoretical definitions of motivation, education, and existing motivational theories. This is followed by a presentation of Company X, as well as the implementation of the research and a discussion of the results. In the theoretical part, we used the descriptive and compilation methods, while in the empirical part, we studied the situation in Company X with the help of a questionnaire. At the end of the diploma thesis, we answered the research questions. We found that employees are most motivated by personal satisfaction and their contribution to their own development. The biggest obstacle to their participation in education is workload. Employees expressed a desire to acquire the most knowledge in the fields of foreign languages and communication skills. They would prefer to be educated during work hours, in the form of practical workshops, lectures, and group training sessions. The data will help Company X decide which training programs to prioritize and when to start implementing them. It will also provide information on the areas and structures employees need the most