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Modelling and optimal control of electric vehicle powertrain containing four independent motors
No full textU posljednjem desetljeću znatno je porasla zastupljenost električnih vozila na tržištu automobila, s ciljem smanjenja emisija štetnih plinova. Porastu popularnosti i zastupljenosti električnih vozila pridonijelo je orijentiranje proizvodnje električne energije prema obnovljivim izvorima energije i napredak u tehnologiji baterija. Zadržavanje konkurentnosti na tržištu električnih vozila koje se svakodnevno razvija zahtjeva brzo prilagođavanje promjenama i kontinuirano unaprjeđenje sustava vozila. U svrhu brzog stjecanja točnih informacija o tehnologijama koje će se potencijalno primijeniti u vozilu, koriste se simulacijski modeli vozila. U ovom radu se razmatra optimalan način upravljanja pogonom električnog vozila sa četiri nezavisna elektromotora kako bi se postigla maksimalna učinkovitost komponenti pogona, s ciljem smanjenja potrošnje električne energije, odnosno povećanja dometa te smanjenja potrošnje. Model pogona izrađen je u ko-simulacijskom okruženju u programima MATLAB / Simulink, i IPG CarMaker. Postavljeno je pet strategija upravljanja pogonom vozila koje su simulacijski ispitane na WLTP voznom ciklusu. Rezultati pokazuju povećani domet vozila uslijed implementacije nove upravljačke logike kojom se stražnji pogon isključuje pri niskim brzinama vozila.Throughout the last decade, the presence of electric vehicles in the car market has increased significantly, with the aim of reducing harmful gas emissions. The main contributors to the increased market share are orientation of electricity production towards renewable energy sources and advances in battery technology. Maintaining competitiveness in the market that is continuously evolving requires the ability to quickly adapt to changes and continuously improve the product, which must be thoroughly tested and verified before entering the market. In order to quickly evaluate the technologies that could potentially be applied in the vehicle, numerical simulations of the vehicle and its subsystem are typically used. This thesis discusses the optimal way to control the powertrain of a vehicle with four independent electric motors to achieve highest efficiency of the powertrain components and thus reduce consumption during a homologation cycle and increase driving range. The vehicle model is set up in MATLAB / Simulink and IPG CarMaker co-simulation environment. Five powertrain control systems are evaluated on WLTP driving cycle. The results point out that completely disengaging the rear wheels reduces power consumption to the greatest extent
Spectrophotometric determination of ionisation constant of resveratrol analogues
No full textPoznavanje konstante ionizacije (Ka) izuzetno je važno prilikom razvoja novih lijekova s obzirom da nam omogućuje predviđanje ponašanja lijekova u fiziološkim uvjetima. Također, ima važnu ulogu kod određivanja ADMET (apsorpcija, distribucija, metabolizam, izlučivanje, toksičnost) svojstava lijekova. Vrijednosti pKa moguće je odrediti različitim metodama poput potenciometrije, kapilarne elektroforeze, tekućinske kromatografije te UV/VIS spektrofotometrije. U ovom radu određene su pKa vrijednosti novih analoga rezveratrola
UV/VIS spektrofotometrijskom metodom. Eksperimentalno određene pKa vrijednosti iznose: 9.80±0.09, 9.94±0.14, 9.10±0.05, 9.44±0.04 i 9.58±0.16.The knowledge of ionisation constant (Ka) is extremly important for the development of new drugs as it allows us to predict the behavior of drugs under psysiological conditions. It also plays a crucial role in determinig the ADMET (absorption, distribution, metabolism, excretion, toxicity) prosperties of drugs. The pKa values can be determined using various methods such as potentiometry, capillary electrophoresis, liquid chromatography, and UV/VIS spectrophotometry. In this study, the pKa values of new resveratrol analogs were determined using the UV/VIS spectrophotometric method. The experimentally determined pKavalues are: 9.80±0.09, 9.94±0.14, 9.10±0.05, 9.44±0.04 and 9.58±0.16
The association between self-compassion and symptoms of eating disorders in high school students
No full textOvaj diplomski rad istražuje povezanost samosuosjećanja i simptoma poremećaja hranjenja kod adolescenata, s posebnim naglaskom na razlike između mladića i djevojaka. Samosuosjećanje, kao koncept koji se sve više prepoznaje kao vitalan za mentalno zdravlje, obuhvaća ljubaznost prema sebi, zajedničku čovječnost i usredotočenu svjesnost kada je u pitanju vlastita patnja.
Cilj istraživanja bio je ispitati razlike u razinama samosuosjećanja i simptomima poremećaja hranjenja kod mladića i djevojaka, kao i utvrditi povezanost između ovih konstrukata. Istraživanje je provedeno u sklopu većeg znanstvenog projekta „Testiranje 5c modela pozitivnog razvoja mladih: tradicionalno i digitalno mobilno mjerenje“ (P.R.O.T.E.C.T.), čiji je nositelj Edukacijsko-rehabilitacijski fakultet u Zagrebu. U istraživanju je sudjelovalo 289 srednjoškolaca, točnije 141 djevojka i 148 mladića. Učenici su pohađali 2. razrede srednjih škola, pri čemu je 127 učenika gimnazije (43,9%), 141 učenik četverogodišnje ili petogodišnje škole (48,8%) te 21 učenik trogodišnje strukovne škole (7,3%). Prosječna dob djevojaka bila je 15,92 godine (SD= 0,36) dok je prosječna dob mladića bila 15,97 godina (SD=0,42). Podaci su prikupljeni putem standardiziranih upitnika, uključujući SCOFF upitnik za simptome poremećaja hranjenja i Skalu samosuosjećanja za mlade (SCSA).
Rezultati istraživanja pokazali su da adolescentice iskazuju znatno višu razinu simptoma poremećaja hranjenja u odnosu na adolescente, pri čemu 42,1% adolescentica brine o gubitku kontrole nad hranom, u usporedbi sa 15,2% adolescenata. Također, 37,1% adolescentica smatra sebe debelima, dok taj postotak među adolescentima iznosi 15,2%. U istom istraživanju, mladići su pokazali značajno veće razine samosuosjećanja od djevojaka. Daljnja analiza pokazuje da se samosuosjećanje negativno korelira sa svim varijablama simptoma poremećaja hranjenja. Regresijska analiza potvrdila je da je samosuosjećanje značajan negativan prediktor simptoma poremećaja hranjenja, a izraženiji je njegov učinak kod adolescentica nego kod adolescenata. Zaključci ovog istraživanja ukazuju na važnu ulogu samosuosjećanja u razvoju i održavanju mentalnog zdravlja adolescenata te u prevenciji poremećaja hranjenja.This thesis investigates the relationship between self-compassion and eating disorder symptoms among adolescents, with a particular focus on differences between boys and girls. Self-compassion, as a concept increasingly recognized as vital for mental health, encompasses kindness toward oneself, understanding of the shared human experience, and mindful awareness regarding one’s own suffering.
The aim of the research was to examine differences in self-compassion levels and eating disorder symptoms between boys and girls, as well as to determine the connection between these constructs. The research was conducted as part of a larger scientific project called “Testing the 5C Model of Positive Youth Development: Traditional and Digital Mobile Measurement” (P.R.O.T.E.C.T.), led by the Faculty of Education and Rehabilitation Sciences in Zagreb. A total of 289 high school students participated in the research, specifically 141 girls and 148 boys. The students were in their second year of high school, with 127 students in gymnasiums (43.9%), 141 students in four or five-year programs (48.8%), and 21 in three-year vocational schools (7.3%). The average age of the girls was 15.92 years (SD = 0.36), while the average age of the boys was 15.97 years (SD = 0.42). Data were collected using standardized questionnaires, including the SCOFF questionnaire for eating disorder symptoms and the Self-Compassion Scale for Adolescents (SCSA).
The research results revealed that adolescent girls exhibit a significantly higher level of eating disorder symptoms compared to boys, with 42.1% of girls concerned about losing control over their eating, compared to 15.2% of boys. Furthermore, 37.1% of girls consider themselves overweight, while this percentage among boys is 15.2%. In the same study, boys demonstrated significantly higher levels of self-compassion then girls. Further analysis indicates that self-compassion negatively correlates with all variables of eating disorder symptoms. Regression analysis confirmed that self-compassion is a significant negative predictor of eating disorder symptoms, with a more pronounced effect among girls than boys.
The conclusions of this research highlight the important role of self-compassion in the development and maintenance of mental health among adolescents, as well as in the prevention of eating disorders
Globalna strukturna analiza rešetkaste palubne konstrukcije poluuronjive plutajuće proizvodne jedinice
No full textThe goal of this thesis is to perform a global structural analysis of the deck truss structure of a semi-submersible Floating Production Unit (FPU). The primary objective of this structural analysis is to verify the global strength of the deck truss structure, ensuring its compliance with the American Bureau of Shipping (ABS) rules for building and classifying Floating Production Installations (FPI). Semi-submersible FPUs are vital in offshore oil and gas production, providing a stable platform for drilling, production, and processing operations in deepwater environments. The deck truss structure is a critical component, supporting the topside facilities and ensuring the overall stability and integrity of the unit. The research involves developing a detailed finite element model (FEM) of the deck truss structure, incorporating material properties, geometric configuration s, and boundary conditions. The model is used to simulate various loading scenarios, including environmental loads, as well as operational loads from equipment and personnel. The analysis aims to identify critical stress points and potential failure modes, ensuring that the deck truss structure meets the required global strength criteria as specified by ABS standards
The distribution of botulinum toxin type A in the rat brain after peripheral application
No full textIako predstavlja najpotentniji otrov poznat čovječanstvu, botulinum toksin tipa A (BT-A) tijekom posljednjih 30-ak godina pronašao je svoje mjesto u terapiji različitih stanja praćenih mišićom hiperkontraktilnošću. Novija ispitivanja ukazala su na njegov antinociceptivni učinak, pri čemu kronična migrena predstavlja prvu bolnu indikaciju za koju je odobren. Osim migrene, pokazuje veliki potencijal i u terapiji različitih vrsta neuropatske boli. Uz terapijsku primjenu, postao je i neizostavni dio u suvremenoj estetskoj medicini, te jedan od globalno najpopularnijih estetskih zahvata, pri čemu je smatran kao siguran i bez ozbiljnih štetnih nuspojava. Dokazi o među-sinaptičkom transportu BT-A u vizualnom, motornom i senzornom sustavu dodatno su potvrdili hipotezu o središnjem mehanizmu djelovanja na bol, s obzirom da BT-A retroaksonalnim transportom s periferije dolazi do prve sinapse unutar leđne moždine, gdje interferira s različitim neurotransmiterskim sustavima. Stoga, postavlja se pitanje ostaje li BT-A na razini leđne moždine ili se transinaptičkim prijenosom prenosi dalje u supraspinalne regije. Cilj ovog istraživanja bilo je ispitati distribuciju BT-A unutar hipotalamusa, hipokampusa, gracilne te facijalne jezgre, nakon jednostrane periferne primjene u stražnju šapu štakora. Imunohistokemijskom metodom praćen je indirektni pokazatelj proteolitičke aktivnosti BT-A, pokidani fragment SNAP-25 proteina. Signal pokidanog SNAP-25 detektiran je unutar svih promatranih regija, pri čemu je kod skupine kojoj je primijenjen specifičan antitoksin za BT-A, uočeno smanjenje intenziteta signala. Taj učinak rezultat je neutralizacije dijela izvanstaničnog BT-A antitoksinom te indirektni dokaz među-sinaptičkog prijenosa BT-A u središnjem živčanom sustavu. Prikazani rezultati otvaraju brojna pitanja o značenju ovih nalaza, posebice u kontekstu sigurnosti dugotrajne primjene BT-A, te zahtijevaju daljnja ispitivanja.Although it represents the most potent toxin known to humanity, botulinum toxin type A (BT-A) has found its place over the last 30 years in the therapy of various conditions accompanied by muscle hypercontractility. Recent studies have indicated its antinociceptive effect, with the first case of approval as treatment for chronic migraine. Besides migraine, it shows great potential in the therapy of various types of neuropathic pain. In addition to therapeutic use, it has also become an indispensable part of modern aesthetic medicine and one of the most popular aesthetic procedures, generally being accepted as safe and without serious adverse side effects. Evidence of BT-A's trans-synaptic transport in the visual, motor, and sensory systems has further confirmed the hypothesis of a central mechanism of action on pain, given that BT-A reaches the first synapse within the spinal cord through retroaxonal transport from the periphery, where it interferes with various neurotransmitter systems. Therefore, the question arises whether BT-A remains at the spinal cord level or is transported trans-synaptically to supraspinal regions. The aim of this research was to examine the distribution of BT-A within the hypothalamus, hippocampus, gracile, and facial nuclei after unilateral peripheral administration to the hind paw of rats. The immunohistochemical method tracked an indirect indicator of BT-A proteolytic activity, the cleaved fragment of the SNAP-25 protein. The signal of cleaved SNAP-25 was detected within all observed regions, with a reduction in signal intensity noted in the group treated with a specific antitoxin for BT-A. This effect is the result of the neutralization of a part of extracellular BT-A by the antitoxin and an indirect proof of BT-A trans-synaptic transport in the central nervous system. The presented results raise numerous questions about the significance of these findings, especially in the context of the safety of long-term BT-A use, and require further investigation
Determination of heavy metals in dietary supplement therapies for inflammatory bowel disease by graphite furnace atomic absorption spectrometry
No full textUključivanje dodataka prehrani standardnoj terapiji za liječenje upalnih bolesti crijeva može pozitivno djelovati na tijek i jačinu bolesti. Kurkumin, andrografolidi, piperin i bosvelične kiseline su biološki aktivne tvari biljnog podrijetla koje svojim protuupalnim, antioksidativnim, i/ili imunomodulatornim svojstvima smanjuju simptome bolesti. Cilj ovog rada bio je procijeniti kvalitetu i sigurnost dodataka prehrani s obzirom na sadržaj teških metala; arsena, kadmija i olova. Budući da su navedeni metali najčešće zastupljeni u niskim koncentracijama, odabrana je tehnika grafitne atomske apsorpcijske spektrometrije nakon postupka mikrovalne digestije. Dobiveni rezultati upućuju na niski sadržaj metala arsena i kadmija. Međutim, sadržaj olova u dva uzorka prelazi dozvoljenu dnevnu izloženost oralnom putem te njihova primjena predstavlja rizik za zdravlje ljudi. U zaključku se ističe potreba stalnog praćenja sigurnosti dodataka prehrani dostupnih na tržištu s obzirom na sadržaj olova.The inclusion of dietary supplements in the standard therapy for the treatment of inflammatory bowel diseases can have a positive effect on the course and severity of the disease. Curcumin, andrographolides, piperine and boswellic acids are biologically active compounds from plants that reduce disease symptoms with their anti-inflammatory, antioxidant and/or immunomodulatory properties. The aim of this work was to evaluate the quality and safety of dietary supplements with regard to the content of heavy metals such as arsenic, cadmium and lead. Since the mentioned metals are primarily present in low concentrations, the graphite atomic absorption spectrometry technique was used after the microwave digestion procedure. The results indicated a low content of metals, including arsenic and cadmium. However, the lead content in two samples exceeds the permitted daily oral exposure, and their use could pose a risk to human health. In conclusion, the need for constant monitoring of the safety of dietary supplements available on the market regarding lead content is emphasized
Analysis and improvement of picking processes in a selected distribution centre
No full textLogistika je znanstvena disciplina koja se bavi upravljanjem tokovima robe, informacija i ljudi od početne točke proizvodnje do krajnjeg korisnika. Glavni cilj logistike je osigurati učinkovito i ekonomično kretanje proizvoda kroz lanac opskrbe, što uključuje planiranje, implementaciju i kontrolu svih logističkih aktivnosti. Logistika obuhvaća brojne aktivnosti, od kojih su najznačajnije upravljanje zalihama, skladištenje, transport, distribucija te upravljanje informacijama u procesima tih aktivnosti. Igra ključnu ulogu u optimizaciji lanca opskrbe, smanjenju troškova, poboljšanju učinkovitosti i povećanju zadovoljstva kupaca. Na primjeru Distribucijskog centra Sv. Helena, dan je detaljan opis svih logističkih djelatnosti koje su zastupljene u jednom distribucijskom centru. Fokus je dan procesu komisioniranja robe, te su na osnovu vremenske analize procesa komisioniranja, predložena tri unaprjeđenja.Logistics is a scientific discipline that deals with the management of the flow of goods, information, and people from the point of origin to the end-user. The main goal of logistics is to ensure efficient and economical movement of products across the supply chain, which includes planning, implementation, and control of all logistic activities. Logistics encompasses numerous activities, among which, picking, transportation, inventory management, distribution, as well as information processing during these processes. It plays a crucial role in optimizing the supply chain, reducing the costs, improving the efficiency, and increasing the customer satisfaction. The thesis focuses on the example of the Sv. Helena Distribution Center to provide, a detailed description of all logistic activities carried out in distribution center. Based on the time analysis of the picking process in the Sv. Helena Distribution Center, three enhancements aimed at improving the picking process are proposed
Consumer acceptance of chatbots measured by the UTAUT2 model
No full textDiplomski rad fokusira se na prihvaćenost chatbotova od strane potrošača, koristeći UTAUT2 model. Predmet rada je analiza kako korisnici percipiraju i prihvaćaju chatbotove u digitalnom okruženju, a cilj je identificirati ključne faktore koji utječu na njihovu odluku o prihvaćanju ove tehnologije. S obzirom na brzinu razvoja tehnologije i njezin sveprisutni utjecaj na svakodnevni život i poslovne procese, razumijevanje načina na koji korisnici reagiraju na inovacije i umjetnu inteligenciju postaje ključno. Istraživanje prihvaćenosti tehnologije omogućuje nam da prepoznamo prepreke i poticaje koji utječu na usvajanje novih rješenja, čime se može poboljšati razvoj i implementacija tehnologija te povećati njihova efikasnost i korisnost za korisnike. U okviru istraživanja, provedena je anketa među 126 ispitanika, pri čemu su analizirane demografske karakteristike, iskustvo i prihvaćenost chatbotova. Rezultati pokazuju da je 70,6% ispitanika koristilo chatbotove, s najvećom popularnošću chatbotova na web stranicama tvrtki i u mobilnim aplikacijama. Istraživanje je otkrilo umjerenu percepciju koristi od chatbotova, visoku ocjenu jednostavnosti njihove upotrebe, te umjerenu zabrinutost za privatnost i sigurnost informacija. Ovi nalazi pružaju uvid u složene odnose između korisnika i tehnologije te ističu važnost razumijevanja faktora koji oblikuju prihvaćenost novih tehnologija.The thesis focuses on consumer acceptance of chatbots, using the UTAUT2 model. The subject of the thesis is the analysis of how users perceive and accept chatbots in the digital environment, with the goal of identifying key factors influencing their decision to adopt this technology. Given the rapid pace of technological development and its pervasive impact on daily life and business processes, understanding how users react to innovations and artificial intelligence is crucial. Research into technology acceptance helps identify barriers and incentives affecting the adoption of new solutions, thereby improving the development and implementation of technologies and enhancing their effectiveness and utility for users. The study involved a survey of 126 participants, analyzing demographic characteristics, experience, and acceptance of chatbots. The results indicate that 70.6% of respondents have used chatbots, with the highest popularity found among chatbots on company websites and in mobile applications. The research revealed a moderate perception of the benefits of chatbots, high ratings for their ease of use, and moderate concern for privacy and information security. These findings provide insight into the complex relationship between users and technology and highlight the importance of understanding the factors that shape the acceptance of new technologies
Beta-carboline ring structure optimisation: the way towards new hybrid compounds with potential antimalary activity
No full textMalarija je zarazna bolest koju uzrokuju različite vrste parazita roda Plasmodium, a od koje umire sve veći broj ljudi.
Harmala alkaloidi β-karbolinskog tipa identificirani su kao spojevi uzori za razvoj novih klasa antimalarika. Promjena
strukture postojećih antimalarika uvođenjem β-karbolinskog motiva pokazala se učinkovitom strategijom za pojačanje
antimalarijske aktivnosti, kao i potencijalno smanjenje rezistencije. S obzirom na poboljšanu antimalarijsku aktivnost
prethodno sintetiziranih hibrida β-karbolina i poznatih antimalarika, u okviru ovog rada odlučili smo modificirati β-
karbolinski prsten. U svrhu njegove priprave, bilo je potrebno sintetizirati N-tosil nitroindol te seriju aminokiselina
modificiranih izocijanidnom skupinom. Dearomatizacijom N-tosil nitroindola serijom aminokiselina modificiranih
izocijanidnom skupinom dobiven je novi triciklički prsten (heksahidropirolo[3,4-b]indol). Novosintetizirani, različito
supstituirani, triciklički prsteni su in situ alkilirani N-propargil indolom ili indolom čime su dobivene ciljne molekule
(16-18). Strukture svih novosintetiziranih molekula potvrđene su standardnim spektroskopskim metodama (1H i 13C
NMR). Dobivene molekule će se u nastavku istraživanja koristiti kao fragmenti za tvorbu hibridnih spojeva s poznatim
antimalaricima metodom Cu(I) katalizirane alkin-azid cikloadicije (klik-reakcijom).Malaria is an infectious disease caused by various species of parasites of the Plasmodium genus, and from which an
increasing number of people are dying. Harmala alkaloids of the β-carboline type have been identified as lead
compounds for the development of new classes of antimalarials. Changing the structure of existing antimalarials by
introducing a β-carboline motif has proven to be an effective strategy for enhancing antimalarial activity, as well as
potentially reducing resistance. Given the improved antimalarial activity of previously synthesized β-carboline hybrids
and common antimalarials, we decided to modify the β-carboline ring in this work. For its preparation, it was necessary
to synthesize a N-tosyl nitroindole and a series of amino acids modified with an isocyano group. A new tricyclic ring
(hexahydropyrrolo[3,4-b indole]) was obtained by dearomatization of N-tosyl nitroindol with a series of amino acids
modified with an isocyano group. Newly synthesized, differently substituted, tricyclic rings were in situ alkylated with
N-propargyl indole or indole to obtain the target molecules (16-18). The structures of all newly synthesized molecules
were confirmed by standard spectroscopic methods (1H and 13C NMR). The obtained molecules will be used in the
continuation of the research as fragments for the formation of hybrid compounds with known antimalarials by the
method of Cu(I) catalyzed alkyne-azide cycloaddition (click-reaction)
The Role of Enterprise Risk Management in Preserving the Value of the Lufthansa Group - an Analysis using the Cash-Flow-at-Risk Method
No full textU dinamičnom poslovnom okruženju, poduzeća se suočavaju sa sve većim brojem rizika kojima je potrebno upravljati. Kao pouzdan alat za identifikaciju i upravljanje rizicima ističe se sustav integriranog upravljanja rizicima. Cilj ovog rada je identificirati i kvantificirati ključne rizike s kojima se suočava Lufthansa Grupa, jedna od najvećih globalnih zrakoplovnih grupacija.
Analiza se provodi primjenom 'top-down' pristupa, kojim se sagledava vanjsko i unutarnje okruženje Grupe. Intrinzična vrijednost poduzeća procjenjuje se metodom diskontiranih novčanih tokova, dok se utjecaj pojedinih rizika na vrijednost procjenjuje korištenjem metode rizičnih novčanih tokova. Rezultati analize pokazuju da najveću prijetnju poslovanju predstavljaju kibernetički rizik, inovacijski rizik i rizik od promjene cijena goriva. Na kraju rada predložene su mjere i strateške preporuke za upravljanje identificiranim rizicima.In a dynamic business environment, companies are exposed to an increasing number of risks that need to be managed. A reliable tool for risk identification and management is Enterprise Risk Management system. The aim of this paper is to identify and quantify the key risks faced by Lufthansa Group, one of the largest global aviation groups.
The analysis is conducted using the 'top-down' approach, which examines both external and internal factors. The intrinsic value of the Group is estimated by using the Discounted Cash Flow Model, while the impact of individual risks on the value is assessed through Cash-Flow-at-Risk Model. The results of the analysis show that the greatest threats to the business are cyber-security risk, innovation risk, and fuel price volatility risk. Finally, the paper proposes measures for managing the identified risks