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Prihranki od naložbe v RPA tehnologijo in uvedbe digitalizacije v računovodsko podjetje
No full textThe thesis explores the implementation of Robotic Process Automation (RPA) in a small accounting firm and its potential to accumulate monetary and time savings. The motivation for this research stems from the author’s practical experience in digital transformation projects, where author directly participated in implementing RPA tools in different organizational structures and industries. The main objective of this thesis is to demonstrate the financial and operational benefits of RPA implementation, particularly through the lens of economic indicators that quantify savings.
The research approach includes an analysis of five accounting processes automated using RPA technology. The study further provides investment assessment with cost estimation, including a cost-benefit breakdown, ROI estimation, and NPV overview through the years. In depth analysis shows that investment in RPA project is more than justified, and that savings are increasing each year even with possible negative impacts.
The key contribution of the thesis is a practical framework for assessing the financial impact of RPA in small businesses. The results confirm that even limited RPA deployments can lead to significant savings and cost reductions. This thesis aims to support decision-makers in understanding both the strategic and economic value of automation in everyday business operations.Magistrsko delo raziskuje implementacijo robotske avtomatizacije procesov (RPA) v majhnem računovodskem podjetju in njen potencial za povečevanjepovečevanje denarnih in časovnih prihrankov. Motivacija za to raziskavo izhaja iz avtoričinih praktičnih izkušenj pri projektih digitalne transformacije, kjer je avtorica neposredno sodelovala pri implementaciji orodij RPA v različnih organizacijskih strukturah in panogah. Glavni cilj tega magistrskega dela je prikazati finančne in operativne koristi implementacije RPA, zlasti skozi prizmo ekonomskih kazalnikov, ki kvantificirajo prihranke.
Raziskovalni pristop vključuje analizo petih računovodskih procesov, avtomatiziranih z uporabo tehnologije RPA. Študija dodatno vključuje oceno naložbe z oceno stroškov, vključno z razčlenitvijo stroškov in koristi, oceno donosnosti naložbe in pregled neto sedanje vrednosti skozi leta. Poglobljena analiza kaže, da je naložba v projekt RPA več kot upravičena in da se prihranki vsako leto povečujejo, kljub morebitnim negativnim vplivom.
Ključni prispevek magistrskega dela je praktičn okvir za oceno finančnega vpliva RPA v malih podjetjih. Rezultati potrjujejo, da lahko tudi omejena uvedba RPA privede do znatnih prihrankov in zmanjšanja stroškov. Namen magistrskega dela je podpreti odločevalce pri razumevanju tako strateške kot ekonomske vrednosti avtomatizacije v vsakodnevnem poslovanju
Izboljšanje učinkovitosti pseudokondenzatorjev na osnovi Co in Ni
No full textThe increasing demand for clean and reliable energy has driven the search for efficient energy storage systems to complement intermittent renewable sources such as solar and wind. While batteries offer high energy density and supercapacitors deliver high power, there is still a need for materials that combine both properties to achieve optimal performance in advanced energy storage applications. Pseudocapacitive materials that utilize fast redox reactions, such as cobalt and nickel hydroxide, offer great promise for energy storage applications, but their performance is strongly dependent on structural features that influence ion diffusion and redox activity. In this thesis, we systematically explored the impact of composition and structural parameters on the electrochemical properties of Co- and Ni-based hydroxide materials.
The structural properties of Co(OH)2 and Ni(OH)2 significantly influence their electrochemical performance. Hydrothermally synthesized Co(OH)2 prepared at lower temperatures exhibits a hydrotalcite-like structure with larger basal spacing and more stacking defects, which promote ion diffusion and enhance redox reactions, resulting in higher capacitance. In contrast, higher synthesis temperature leads to the formation of cobalt carbonate hydroxide with restricted ion accessibility and reduced pseudocapacitive properties. Similarly, for Ni(OH)2, the incorporation of carbonate increases with the temperature of hydrothermal synthesis. Using hexamethylenetetramine (HMT), it is possible to prepare hydroxide with minimal carbonate content in the lower temperature range, where HMT decomposition is incomplete. While using urea as a precipitating agent, the carbonate incorporation cannot be avoided. The presence of carbonate in Ni(OH)2 hinders electrochemical performance. These findings underscore the importance of structural features, particularly minimizing carbonate content, for optimizing pseudocapacitors\u27 performance.
To enhance the voltage window and improve capacitance, we incorporated redox-inactive M3+ ions (Al3+, Ga3+, and In3+) into the Co(OH)2 and Ni(OH)2, aiming to modify the electronic structure and consequently suppress the oxygen evolution reaction (OER). While CoAl- and NiAl-LDH showed promising results, a mismatch in cation size of larger Ga3+ and In3+ led to poorly crystalline powders. Nevertheless, the suppression of OER activity was successful for all the samples.
However, carbonate intercalation was identified as a limiting factor for capacitance for all M3+ incorporated hydroxides, which we avoid in the next steps of materials optimization.
An alternative approach to enhance electrochemical performance and capacitance involved expanding the basal plane distance of layered double hydroxides (LDHs) by the intercalation of larger organic anions. Specifically, ethyl sulfate (ES) and n-octyl sulfate (OS) were incorporated into CoAl-LDH by coprecipitation, increasing the interlayer spacing. CoAl-LDH materials facilitated suppression of the OER, widened the voltage window and improved capacitance. While ES showed increased enhancement of capacitance, there was also a large amount of carbonate ions present in the structure, indicating ongoing anion exchange. The OS ion exhibited superior performance among all prepared materials in this work. Furthermore, it showed resistance to exchange with carbonate, suggesting its potential for improved cycle life.
Finally, the formation of a nanocomposite by incorporating gold nanoparticles into CoAl-LDH was explored. Through the intercalation of the terephthalate anion (TA), the basal plane distance of the LDH was expanded, providing a suitable environment for gold nanoparticle growth without disrupting the LDH structure. The TA anions were exchanged with the tetrachloroaurate anions, followed by the growth of gold nanoparticles within the basal space. The resulting CoAl-TA-LDH/Au nanocomposite exhibited a significant increase in surface area and charge storage capacity, with performance surpassing best-performing Co(OH)2. This enhancement is attributed to the synergistic effects of the gold nanoparticles, which facilitated improved ion diffusion and enhanced the Co redox behavior.Razvoj učinkovitih hranilnikov energije, ki dopolnjujejo izrabo energije iz obnovljivih virov (veter, sonce,..) je ključen za zanesljivo električno oskrbo. Pri tem imajo pomembno vlogo sistemi, ki hkrati nudijo visoko gostoto energije in veliko moč, ter omogočajo hitre cikle polnjenja in praznjenja. Baterije dosegajo odlično gostoto energije, medtem ko superkondenzatorji visoko moč. Združitev teh dveh lastnosti bi prinesla optimalne rešitve za pametne sisteme shranjevanja energije. Pseudokondenzatorji, na primer na osnovi nikljevega in kobaltovega hidroksida, temeljijo na izjemno hitrih redoks reakcijah, ki prispevajo k kapacitivnosti. Njihova zmogljivost je tesno povezana s strukturni lastnostmi, ki določajo difuzijo ionov in redoks aktivnost elektrod.
V doktorski nalogi smo sistematično proučili, kako strukturni parametri vplivajo na elektrokemijske lastnosti nikljevih in kobaltovih hidroksidnih materialov. Osredotočili smo se na vlogo morfologije, kemijske sestave ter strukture pri optimizaciji elektrod za pseudokondenzatorje. Pri analizi materialov smo uporabili različne karakterizacijske tehnike. Kristalno strukturo smo določevali s pomočjo rentgenske difrakcije (XRD), medtem ko smo morfologijo podrobno analizirali z vrstičnim (SEM) in presevnim (TEM) elektronskim mikroskopom. Elektrokemijske lastnosti smo ovrednotili s ciklično voltametrijo ter polnjenjem in praznenjem pri konstantni gostoti toka (GCD), ki je bil ključen za izračun specifične kapacitivnosti. Dodatni vpogled v kemijsko stanje kobaltovih in nikljevih kationov pa smo pridobili z in situ rentgensko absorpcijsko spektroskopijo (XAS).
Vpliv temperature pri hidrotermalni sintezi kovinskih hidroksidov ima pomembno vlogo pri izražanju strukturnih ter elektrokemijskih lastnosti Co(OH)2 kot tudi Ni(OH)2, s čimer neposredno vpliva na učinkovitost shranjevanja energije. Pri nižjih temperaturah sinteze (80 °C in 100 °C) tvori Co(OH)2 strukturo z razmeroma širokim medslojnim razmikom (9.3 Å). Takšna ureditev izboljša difuzijo ionov elektrolita in elektrokemijsko dostopnost Co2+ mest, kar je bistveno za učinkovito delovanje pseudokondenzatorjev. Prisotnost redoks vrhov in dobro definirane krivulje polnjenja in praznjenja potrjujejo prisotnost faradičnih procesov. Posledično dosegajo ti vzorci visoko kapacitivnost, pri čemer je vzorec sintetiziran pri 100 °C dosegel najvišjo vrednost.
Pri povišanju temperature sinteze (120 °C in 140 °C), se je struktura Co(OH)2 preoblikovala v monoklinski kobaltov karbonat hidroksid, kjer so karbonatni anioni močno vezani v kristalno mrežo. Čeprav imajo ti vzorci večjo specifično površino, njihova struktura ovira difuzijo ionov in omejuje dostop do elektrokemijsko aktivnih mest, kar vodi v manj izrazito redoks aktivnost. Iz rezultatov je razvidno, da je gostota energije pri Co(OH)2 močno odvisna od njegove strukturne ureditve, zlasti od razdalje med plastmi hidroksida in dostopnosti Co2+ kationov. Ni(OH)2 tvori pri nižjih temperaturah sinteze (80 °C in 100 °C) manj urejeno α-strukturo z razširjenimi razmiki med sloji, kar je posledica delnega razpada in vgradnje razpadnih produktov heksametilentetramina (HMT). Ta struktura omogoča lažji dostop in difuzijo ionov, kar je bilo razvidno iz elektrokemijskih meritev in visoke vrednosti kapacitivnosti. V primeru povišanja temperature (120 °C in 140 °C), se HMT popolnoma razgradi, kar vodi do vgradnje karbonata in nastanka nikljevega karbonata hidroksida. Ta omejuje difuzijo ionov in zmanjšuje dostop do redoks aktivnih Ni2+ mest, s čimer se kapacitivnost in gostota energije zmanjšata. Pri vzorcih, pripravljenih z ureo, temperatura sinteze ni imela opaznega vpliva, saj so vsi pokazali slabo elektrokemijsko zmogljivost. Že pri nižjih temperaturah razgradnje uree se tvorijo karbonatne zvrsti, ki se vgradijo v strukturo in zmanjšujejo dostopnost redoks aktivnih Ni2+ mest. Pri višjih temperaturah pa kristalizirajo v nikljev karbonat hidroksid, kar kapacitivnost še dodatno zniža.
Vgradnja Al3+ kationov v strukturo Co(OH)2 ter Ni(OH)2 tvori hidrotalcitno strukturo. Z dodatkom kationov z večjim ionskim radijem, Ga3+ in In3+ , je prav tako nastala hidrotalcitna struktura, vendar z izrazito razširjenimi difrakcijskimi vrhovi, kar nakazuje na večjo strukturno neurejenost. Zaradi različnih velikosti ionskih radijev je bila vgradnja kationov v strukturo nepopolna in se ni skladala s pričakovanim razmerjem M2+/M3+ , ki je značilen za hidrotalcitno strukturo. Kljub temu sta bila CoAl-LDH in NiAl-LDH elektrokemijsko aktivna, pri čemer NiAl-LDH dosega bistveno večjo kapacitivnost. Pri CoAl-LDH je vgradnja Al3+ kationa povzročila premik oksidacijskega vrha Co2+/3+ iz vrednosti 1.10 V, kar je značilno za Co(OH)2, na vrednost 1.43 V. Kapacitivnost CoAl-LDH (128 F g-1 pri 1 A g-1) ni presegala najboljšega vzorca Co(OH)2 pripravljenega pri 80 °C (220 F g-1 pri 1 A g-1).
Ni(OH)2 je dosegel kapacitivnost 700 F g-1 pri 1 A g-1, primerljivo z najboljšim vzorcem Ni(OH)2 pripravljenim pri 100 °C s pomočjo heksametilentetramina (680 F g-1 pri 1 A g-1). Karbonatni anion je prisoten v vseh vzorcih, podobno kot je bilo predstavljeno pri Co(OH)2 ter Ni(OH)2, kar zmanjšuje celotno elektrokemijsko zmogljivost.
Vgradnja različnih organskih anionov v strukturo CoAl-LDH je bila namenjena povečanju razmika med sloji hidroksidov in odpravi karbonatnih ionov, s čimer bi se odprle difuzijske poti za ione elektrolita in izboljšala dostopnost redoks aktivnih mest. Po vgraditvi se je razmik med plastmi v primerjavi z CoAl-CO3-LDH za vzorec CoAl-ES-LDH povečal na 0.784 nm in na 2.159 nm pri CoAl-OS-LDH, kar neposredno odraža uspešno vgradnjo anionov. Kot je bilo pričakovano, je CoAl-OS-LDH izkazal najboljšo elektrokemijsko zmogljivost, saj je razmik med plastmi izboljšal transport ionov elektrolita in dostopnost aktivnih mest. Kapacitivnost za ta vzorec je dosegala vrednost 1070 F g-1 pri 1 A g-1, kar presega tako CoAl-CO3-LDH (128 F g-1 pri 1 A g-1) kot CoAl-ES-LDH (870 F g-1 pri 1 A g-1).
Drugi pristop za izboljšanje kapacitivnosti je bila priprava nanokompozita z Au nanodelci. V strukturo CoAl-LDH smo vgradil tereftalat, kot prekurzor za pripravo nanokompozita. Primerjava difrakcijskih vrhov z CoAl-CO3-LDH je pokazala uspešno vgraditev tereftalata. Difrakcijski vrhovi so se premaknili k manjšim kotom in pojavila sta se dva seta difrakcijskih vrhov za dve fazi materiala z različnim načinom zlaganja tereftalata. Z anionsko izmenjavo z [AuCl4]- so bili vgrajeni nanodelci zlata, kar je vodilo do oblikovanja nanokompozita. Pri tem nismo več zaznali dveh setov difrakcijskih vrhov, kar kaže na uspešno rekristalizacijo LDH, pri čemer se je ohranila hidrotalcitna struktura. Nanokompozit je dosegel kapacitivnost 740 F g-1 pri 1 A g-1, kar je preseglo vrednosti CoAl-LDH z vgrajenim karbonatom ali tereftalatom. Vgradnja tereftalata in nanodelcev zlata bistveno poveča elektrokemijsko zmogljivost CoAl-LDH. Razširjeni razmik med sloji omogoča učinkovitejšo difuzijo ionov, vgrajeni nanodelci zlata pa izboljšajo prevodnost in ustvarijo dodatna elektrokemijsko aktivna mesta
Dijana Jotanović: Optimization of the system for developing and monitoring competencies in the company
No full textDiplomsko delo obravnava optimizacijo sistema za razvoj in spremljanje kompetenc v podjetju letalske industrije, kjer je usposobljenost zaposlenih neposredno povezana z zagotavljanjem kakovosti, varnosti in skladnosti z mednarodnimi standardi. Posebna pozornost je namenjena izpolnjevanju zahtev standarda ISO 9001, ki predpisuje sistematično določanje, ocenjevanje in dokumentiranje kompetenc, ter regulative EASA Part 21G, ki določa stroge zahteve glede usposobljenosti kadrov v proizvodnih organizacijah. V uvodnem delu so predstavljeni pomen kompetenc za učinkovito delovanje podjetja, ključne regulativne zahteve ter teoretični okvir uporabe matrike kompetenc kot orodja za sistematično spremljanje znanj in veščin zaposlenih.
Analiza obstoječega stanja matrike kompetenc v podjetju je pokazala več pomanjkljivosti, med drugim odsotnost faktorja pomembnosti posameznih kompetenc, omejeno preglednost matrike kompetenc, pomanjkljivo beleženje izvedenih usposabljanj ter pomanjkanje sistematičnega merjenja učinkov izvedenih izboljšav. Na podlagi ugotovitev je oblikovan predlog optimizacije, ki vključuje izboljšano definicijo delovnih mest, uvedbo faktorja pomembnosti posameznih kompetenc, nadgrajen postopek ocenjevanja kompetenc z jasno lestvico, sodoben sistem beleženja usposabljanj ter kazalnike uspešnosti za spremljanje napredka. Predlagani model omogoča večjo preglednost, ciljno usmerjena usposabljanja, zmanjšanje operativnih tveganj in večjo skladnost z mednarodnimi standardi. Zaradi prilagodljive zasnove ima model širšo uporabno vrednost tudi v drugih visoko reguliranih industrijah, kjer je kompetentnost kadra ključnega pomena.The thesis addresses the optimisation of a system for the development and monitoring of competencies in an aerospace industry company, where employee competence is directly linked to ensuring quality, safety, and compliance with international standards. Particular attention is devoted to fulfilling the requirements of the ISO 9001 standard, which prescribes the systematic determination, assessment, and documentation of competencies, as well as the EASA Part 21G regulation, which sets strict requirements regarding personnel qualifications in production organisations. The introductory part of the thesis presents the importance of competencies for the effective functioning of the company, the key regulatory requirements, and the theoretical framework of using a competency matrix as a tool for systematically monitoring the knowledge and skills of employees.
The analysis of the current state of the competency matrix in the company revealed several shortcomings, including the absence of a weighting factor for individual competencies, limited transparency of the competency matrix, insufficient recording of completed training, and a lack of systematic measurement of the effects of implemented improvements. Based on these findings, an optimisation proposal was developed, whitc includes an improved definition of job positions, the introduction of a weighting factor for individual competencies, an upgraded competence assessment process with a clear rating scale, a modern training recording system, and performance indicators for monitoring progress. The proposed model enables greater transparency, more targeted training, reduced operational risks, and improved compliance with international standards. Due to its adaptable design, the model also has broader applicability in other highly regulated industries where staff competence is of critical importance
Key concepts for introducing chaos theory to secondary education
No full textThe understanding of nonlinear dynamics requires a solid background on differential equations, calculus, and numerical analysis. This is why the teaching of nonlinear dynamics and chaos is integrated in the later years of most curriculums of University Departments in the natural sciences. With chaotic systems being so abundant in real life though, numerous nonlinear dynamics principles and chaotic phenomena can be explained to younger students through simple definitions and examples, by circumventing rigorous mathematical descriptions. Many such seminars have been considered already for chaos theory [1-3] and its applications [4,5], either to secondary, or early university students. This work discusses the prospect of introducing concepts from the theory of dynamical systems and chaos in earlier stages of education. A catalogue of key underlying concepts that can be covered in a syllabus are presented, and the importance of each one are discussed
Recognition of Greek Orthodox hymns using audio fingerprint techniques
No full textAudio fingerprinting was originally developed for music song identification, and over the years has been used for many more cases. With fingerprinting, an equivalent signature of the audio signal is saved in a simple form, so that it can be easily compared with another fingerprint. In this work, an audio fingerprinting algorithm is developed for the recognition of Greek Orthodox hymns. The main difference between music songs and Greek Orthodox hymns is the absence of music instruments, as there is only the chanter\u27s voice. The test dataset consists of 10 hymns, and for each hymn there are 5 different performances, creating a dataset of 50 performances. Several tunable parameters of the fingerprinting technique are tested, like the parameters of the Hamming window, the frequency spectrum, the sample duration, and the sample noise, to find the differences in Greek Orthodox hymns. The recognition results for all cases are positive. The algorithm, in most cases, had a high recognition rate. even with noisy samples
Motion control of a mobile robot based on a chaotic iterative map
No full textIn this work, the problem of designing an efficient chaotic path planning generator for exploring an area is studied. To achieve so, a Chaotic Random Bit Generator (CRBG) is first constructed. The randomness of the generator was tested and verified by the FIPS statistical package. Then, the proposed CRBG is utilized to produce the chaotic motion commands for an autonomous mobile robot moving in a 2D area, in four or eight different directions. A series of simulations have been performed in Matlab, in order to evaluate the efficiency of the proposed method and the results show that the motion in eight directions gives better results with respect to the coverage rate while also the multiple visits to the same cells have been decreased significantly
On ps-supplement submodules
No full textIn this work, we introduce ps-supplement submodules as a kind of supplements. Specifically, a submodule V of a module M is referred to as a ps-supplement if there exists another submodule U⊆M such that M=U+V and the intersection U∩V is projective semisimple. We demonstrate that, over an arbitrary ring, the collection PS of short exact sequences of the form 0⟶M⟶ψN⟶ϕK⟶0, where Im(ψ) is a ps-supplement in N, constitutes a proper class. In addition, we explore several homological aspects of this class, including the symmetry of the relations between the modules. Finally, we provide that a ring R is a left SI-ring with essential socle if and only if every left R-module is ps-supplemented
