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Određivanje energetski optimalne putanje šestosnih industrijskih robotskih manipulatora primjenom strojnog učenja i memetičkih algoritama : doktorski rad
No full textThis dissertation focuses on the energy optimization of serial robotic
manipulators’ trajectories. Due to the frequent repetition of trajectories, their optimization can lead to significant energy savings. The first step is modeling the
energy consumption of the manipulator concerning the trajectory defined by positions, velocities, and accelerations in joint space. Two approaches are presented:
a classical analytical model based on the Lagrange-Euler algorithm and machine learning methods. The applied algorithms include a multilayer perceptron,
support vector machines, a passive-aggressive regressor, and gradient-boosted
trees. These algorithms were tested on three datasets: real (collected in a laboratory), simulated, and synthetic (generated from real data). The models were
trained using cross-validation and optimized via grid search, then tested on real
data. Results indicate that models trained on simulated data perform worse due
to deviations from the real IRM, whereas synthetic data allowed for models nearly
identical to those trained on real data. The best-performing models were based
on a multilayer perceptron and were incorporated into the optimization process
as part of the fitness function. Optimization was performed using a genetic algorithm, with the best performance achieved through random gene recombination
(95%) and mutation (5%). The algorithm was further enhanced with a memetic
approach featuring local search. Informed search improved trajectories by an
average of 59% compared to randomly selected parameters, demonstrating the
potential of the memetic approach for trajectory energy optimization.Ovaj rad bavi se energetskom optimizacijom putanja serijskih robotskih manipulatora. Zbog čestog ponavljanja putanja, njihova optimizacija može donijeti značajne uštede. Prvi korak je modeliranje potrošnje energije manipulatora u odnosu na putanju definiranu pozicijama, brzinama i akceleracijama u zglobovskom prostoru. Predstavljena su dva pristupa: klasični analitički model temeljen na Lagrange-Eulerovom algoritmu te metode strojnog učenja. Korišteni su višeslojni perceptron, strojevi potpornih vektora, pasivno-agresivni regreso i gradijentno pojačana stabla. Algoritmi su primijenjeni na tri skupa podataka: stvarni (prikupljen u laboratoriju), simulirani i sintetički (generiran iz stvarnih podataka). Modeli su trenirani višestrukom validacijom i optimizirani pretragom rešetke, a testirani na stvarnim podacima. Rezultati pokazuju da su modeli trenirani na simuliranim podacima slabiji zbog odstupanja od stvarnog IRM-a, dok su sintetički podaci omogućli modele gotovo jednake kao stvarni. Najbolji modeli temelje se na višeslojnom perceptronu i koriste se u optimizacijskom procesu
kao dio funkcije pogodnosti. Optimizacija se provodi genetskim algoritmom, pri čemu se najboljom pokazala nasumična rekombinacija gena (95%) uz mutaciju (5%). Algoritam se nadograđuje memetskim pristupom s lokalnim pretraživanjem. Informirano pretraživanje poboljšava putanju u prosjeku za 59% u odnosu na nasumične parametre, što ukazuje na potencijal memetskog pristupa za optimizaciju putanja
Prediction of Energy Consumption in SCARA Robots Using Machine Learning and Data Synthesis
No full textOvaj rad istražuje primjenu umjetnih neuronskih mreža (UNM) za predviđanje potrošnje energije SCARA industrijskog robota. Modeli su trenirani na originalnim i sintetičkim podatcima, pri čemu su sintetički podatci generirani pomoću TVAE modela. Analiza pokazuje da neuronske mreže mogu precizno predvidjeti potrošnju snage, dok su rezultati na sintetičkim podatcima pokazali minimalna odstupanja u odnosu na stvarne podatke. Ovi rezultati potvrđuju mogućnost korištenja sintetičkih podataka za treniranje modela, čime se smanjuju troškovi i vrijeme eksperimentalnih mjerenja.This paper explores the use of artificial neural networks (ANN) for predicting the power consumption of a SCARA industrial robot. Models were trained on both real and synthetic data, with synthetic datasets generated using the TVAE model. The analysis demonstrates that neural networks can accurately predict power consumption, while results on synthetic data showed minimal deviations compared to real data. These findings confirm the feasibility of using synthetic data for model training, reducing both cost and time associated with experimental measurements
The impact of the COVID pandemic on gender equality
No full textRodna neravnopravnost predstavlja problem na tržištu rada i u cjelokupnom društvu koji se
očituje kroz nejednak pristup pravima, resursima i mogućnostima ovisno o spolu. Proizlazi iz
kulturološki i društveno određenih rodnih uloga koje su dodijeljene muškarcima i ženama.
Muškarci se smatraju hraniteljima koji vrše plaćeni rad, dok su žene majke i njegovateljice.
Radi toga žene, osim plaćenog rada, obavljaju većinu neplaćenog rada kod kuće. Također
odgovorne su za većinu mentalnog rada koji se odnosi na vođenje kućanstva. Prije pojave
pandemije COVID-19 postignut je određeni napredak u postizanju rodne ravnopravnosti, no
pojavom pandemije stvoreni su novi problemi usklađivanja zahtjeva plaćenog posla s
povećanim zadacima u kućanstvu. U radu su istraživane rodne uloge u okviru plaćenog i
neplaćenog rada te su predstavljeni pojmovi pod nazivom mentalni rad i kinkeeping kao dio
neplaćenog rada. Prikazana je problematika neravnomjerne raspodjele obaveza između
muškaraca i žena te je analiziran je utjecaj COVID-19 pandemije na rodnu ravnopravnost i
raspodjelu obaveza. Predstavljene su mjere i politike za postizanje veće rodne ravnopravnosti.
Zaključeno je da pandemija osim što je utjecala na zdravlje, utjecala je i na položaj žena u
društvu i na tržištu rada. Povećao se teret neplaćenog rada kod kuće kao i teret mentalnog
opterećenja te su se pogoršali radni i životni uvjeti žena. Ne poduzimanje adekvatnih mjera za
rješavanje nerazmjernog utjecaja COVID-19 na žene dovodi do rizika da se postignuti napredak
ugrozi te da se sudjelovanje žena na tržištu rada dodatno smanji u budućnosti. Stoga je bitno
kreirati rodno osjetljive politike s ciljem osiguravanja jednakih ekonomskih prilika za žene
nakon krize izazvane COVID-19
Neuron-restricted cytomegalovirus latency in the central nervous system regulated by CD4+ T-cells and IFN-γ
No full textAll human herpesviruses establish latency following the resolution of the primary infection. Among these, α-herpesviruses HSV-1, HSV-2 and VZV establish latency in neurons, whereas neurons are not traditionally considered a site of latency for other herpesviruses. Using a combination of in vivo murine models and ex vivo human fetal tissues, we discovered that cytomegalovirus (CMV), a ubiquitous β-herpesvirus, can persist in neurons and that CD4+ T-cell-derived interferon-gamma is critical in restricting active viral replication in this cell type. Furthermore, we show that mouse CMV can establish latency in neurons and that CD4+ T-cells are essential in preventing viral reactivation. Our findings may have translational significance because human cytomegalovirus (HCMV) is the leading cause of congenital viral infections resulting in neurodevelopmental and neuroinflammatory lesions with long-term functional sequelae
Market Research for the Needs of Introducing a New Service – Food Intolerance
No full textU radu se istražuje tržišni potencijal i ključni faktori za uspješno uvođenje nove usluge testiranja
intolerancije na hranu. Cilj istraživanja je analizirati spremnost korisnika na prihvaćanje ove
usluge, identificirati ključne elemente koji utječu na zadovoljstvo korisnika te ispitati koje
demografske karakteristike korisnika utječu na njihovu zainteresiranost za uslugu. U teorijskom
dijelu rada obrađeni su koncepti istraživanja tržišta, zadovoljstva korisnika te specifičnosti
usluga u zdravstvenom sektoru. Empirijsko istraživanje provedeno je anketnim ispitivanjem, a
prikupljeni podaci analizirani su statističkim metodama, uključujući Chi-squared test. Rezultati
pokazuju da ključni faktori poput brzine dobivanja testa, točnost testa, cijena, lokacija,
korisnička podrška te ostali elementi utječu na ukupno zadovoljstvo korisnika. Također ovo
istraživanje je pokazalo da su za većinu ispitanika pri odabiru usluge testiranja intolerancije na
hranu najvažniji upravo preciznost testa i njegova cijena. Istraživanje je pokazalo da visina
primanja značajno utječe na zainteresiranost korisnika za uslugu, dok spol i obrazovanje nemaju
statistički značajan utjecaj. Dobiveni rezultati mogu poslužiti kao temelj za oblikovanje
strategije uvođenja usluge na tržište.The paper explores the market potential and key factors for the successful introduction of a new
food intolerance testing service. The aim of the research is to analyze users' willingness to
accept this service, identify the key elements that influence customer satisfaction, and examine
which demographic characteristics affect users' interest in the service. The theoretical part of
the paper covers concepts related to market research, customer satisfaction, and the specifics of
services in the healthcare sector. The empirical research was conducted through a survey, and
the collected data were analyzed using statistical methods, including the Chi-squared test. The
results show that key factors such as test processing speed, test accuracy, price, location,
customer support, and other elements influence overall user satisfaction. Additionally, the study
revealed that test accuracy and price are the most important factors for most respondents when
choosing a food intolerance testing service. The research also found that income level
significantly affects users' interest in the service, while gender and education do not have a
statistically significant impact. The obtained results can serve as a basis for developing a market
entry strategy for the service
THE RIGHT TO A FAIR TRIAL IN CRIMINAL PROCEEDINGS ACCORDING ARTICLE 6 OF THE EUROPEAN CONVENTION ON HUMAN RIGHTS
No full textU ovom radu objašnjeno je postupanje prema članku 6. Europske konvencije ljudskim pravima i to dio koji se odnosi na pošteno suđenje u kaznenim postupcima. Radi utvrđivanja svojih prava i obveza građanske naravi ili u slučaju podizanja optužnice za kazneno djelo protiv njega svatko ima pravo da zakonom ustanovljeni neovisni i nepristrani sud pravično, javno i u razumnom roku ispita njegov slučaj. Pravo na pošteno suđenje zajamčeno Europskom konvencijom o ljudskim pravima i temeljnim slobodama i njegov kaznenopravni aspekt nadalje su razrađeni kroz niz institucionalnih i postupovnih jamstava kjučnih za ostvarenje pravičnosti kaznenih postupaka, a time i vladavine prava. Primjerima sudske prakse Europskog suda za ljudska prava u predmetima protiv Republike Hrvatske prikazane su povrede jamstava, gdje do izražaja upravo dolazi autonomno tumačenje.This thesis explains the procedure according to Article 6 of the European Convention on Human Rights, specifically the part that relates to the right to a fair trial in criminal proceedings. In order to determine one’s civil rights and obligations, or in the case of being charged with a criminal offence, everyone has the right to fair and public hearing within a reasonable time by an independent and impartial tribunal established by law. The right to a fair trial, guaranteed by the European Convention on Human Rights and Fundamental Freedoms and its criminal law aspect, is further elaborated through a series of institutional and procedural safeguards essential for ensuring the fairness of criminal proceedings, and thus the rule of law. Through examples of the case law of European Court of Human Rights in cases against the Republic of Croatia, violations of these safeguards are presented, highlighting the importance of autonomous interpretation
Nutritional quality of tofu on the Croatian market
No full textTofu je biljni proizvod podrijetlom iz Kine koji se sve više konzumira kao zamjena za namirnice životinjskog podrijetla. Kvaliteta i nutritivna vrijednost soje kao i operacije u proizvodnom procesu (namakanje soje, dodatak učvršćivača, jačina prešanja, dimljenje, vrsta pakiranja) utječu na kvalitetu i nutritivnu vrijednost konačnog proizvoda. Nutritivna deklaracija obavezan je podatak na prehrambenim proizvodima, a Nutri-Score je jednostavna slikovna oznaka nutritivne kvalitete koja potrošačima može pomoći u donošenju informiranih odluka o kupnji. Cilj ovog istraživanja bio je analizirati i usporediti sastav i nutritivnu kvalitetu svježeg i dimljenog tofua te proizvoda od tofua dostupnih na hrvatskom tržištu. Istraživanje je provedeno analizom podataka s deklaracija 34 proizvoda u svrhu usporedbe i izračuna Nutri-Score vrijednosti. Utvrđeno je da tofu-proizvodi u usporedbi sa svježim i dimljenim tofuom imaju znatno raznolikiji sastav, statistički značajno veću energijsku vrijednost, veći udio masti, ugljikohidrata i soli. Zbog niske energijske vrijednosti, manjeg udjela soli, masti i šećera, svježi i dimljeni tofu imaju povoljnije Nutri-Score oznake (A, odnosno B) od tofu-proizvoda (oznaka C).Tofu is a plant-based product originating from China that is increasingly being consumed as a substitute for animal-based foods. The quality and nutritional value of soybeans, as well as the operations in the production process (soaking soybeans, addition of coagulants, pressing intensity, smoking, type of packaging), influence the quality and nutritional value of the final product. Nutritional labeling is mandatory on food products, and the Nutri-Score is a simple visual label of nutritional quality that can help consumers to make informed purchasing decisions. The aim of this study was to analyze and compare the composition and nutritional quality of fresh and smoked tofu, as well as tofu-based products available on the Croatian market. The research was conducted by analyzing data from the labels of 34 products to compare and calculate their Nutri-Score values. It was found that tofu-based products, in comparison to fresh and smoked tofu, have a significantly more varied composition, statistically higher energy value, and a greater proportion of fat, carbohydrates, and salt. Due to their lower energy value, and lower content of salt, fat, and sugar, fresh and smoked tofu have more favorable Nutri-Score ratings (A and B, respectively) compared to tofu-based products (rating C)
The role of non-invasive diagnostic procedures in diagnosing and assessing the risk of coronary heart disease
No full textKronični koronarni sindrom (CCS) jedan je od glavnih uzroka morbiditeta i mortaliteta u svijetu, s velikim socioekonomskim značajem. CCS se može prezentirati nizom kliničkih manifestacija ili sindroma koji nastaju zbog strukturnih i/ili funkcionalnih promjena povezanih s kroničnim bolestima koronarnih arterija i/ili mikrocirkulacije. S obzirom na trenutačno razumijevanje složenih patofizioloških mehanizama koji vode razvoju CCS-a, u kliničkoj se praksi upotrebljavaju dva temeljna neinvazivna dijagnostička modaliteta: anatomski (koronarna kompjutorizirana tomografska angiografija - CCTA) i funkcionalni (stres ehokardiografija – SE, magnetska rezonanca srca – CMR, jednofotonska emisijska kompjutorizirana tomografija – SPECT, pozitornska emisijska tomografija –PET). Funkcionalne neinvazivne dijagnostičke metode omogućuju procjenu protoka krvi kroz koronarne arterije, uočavanje poremećaja perfuzije miokarda, evaluaciju poremećaja kontraktilnosti miokarda te procjenu prisutnosti eventualnih ožiljnih promjena u miokardu. S druge strane, anatomsko oslikavanje putem CCTA može procijeniti težinu koronarne stenoze, kao i sastav i morfologiju plaka, identificirajući značajke visokorizičnog plaka te pružajući dodatne informacije o ukupnom kardiovaskularnom opterećenju. Ovakva sveobuhvatna procjena omogućuje rano postavljanje dijagnoze CCS-a, određivanje prostorne distribucije ishemije prema zahvaćenim koronarnim segmentima te identifikaciju pacijenata s povišenim rizikom za nepovoljne kliničke ishode, koji bi potencijalno mogli imati korist od invazivnih intervencija poput revaskularizacije.Chronic coronary syndrome (CCS) is one of the leading causes of morbidity and mortality worldwide, with significant socioeconomic impact. CCS can present with a variety of clinical manifestations or syndromes that result from structural and/or functional changes associated with chronic coronary artery disease and/or microcirculation disorders. Based on the current understanding of the complex pathophysiological mechanisms leading to the development of CCS, two fundamental non-invasive diagnostic modalities are used in clinical practice. These include anatomical imaging (coronary computed tomography angiography – CCTA) and functional imaging (stress echocardiography – SE, cardiac magnetic resonance – CMR, single-photon emission computed tomography – SPECT, positron emission tomography – PET). Functional non-invasive diagnostic methods enable the assessment of blood flow through the coronary arteries, the detection of myocardial perfusion abnormalities, evaluation of myocardial contractility disorders, and the identification of potential myocardial scarring. On the other hand, anatomical imaging using CCTA can evaluate the severity of coronary stenosis, as well as the structure and morphology of plaques, identifying features of high-risk plaques and providing additional information on the overall cardiovascular risk. This comprehensive assessment enables early diagnosis of CCS, determination of the spatial distribution of ischemia according to the affected coronary segments, and identification of patients at increased risk for adverse clinical outcomes, who may benefit from invasive interventions such as revascularization
Pharmacogenomics - impact on cytochrome p450 system and drug metabolism
No full textTo sum up pharmacogenomics is a broad and evolving field in genetics and pharmacological perspective. The CYP enzyme system plays a central role in metabolizing approximately 75 % of all medication. This system is categorized into 3 families- CYP1, CYP2 and CYP3. The isoforms CYP3A4 and CYP2D6 alone make about 50 % the drug metabolism. Genetic polymorphisms, that can be grouped according to different types of metabolizers such as UM, EM, IM and PM significantly affect efficacy and toxicity of prescribed drugs. But not only the genetic predisposition is responsible for the metabolization of medications, also external factors such as other drugs, that can act as CYP inducers and CYP inhibitors, or diseases have a big impact on activity of biotransformation and can be summarized under the term phenoconversion. Postmortem studies demonstrate how important it is to consider those drug- drug-gene interactions are. To reduce the risk of adverse events and increase the therapeutic effect of prescribed drugs, databases such as CPIC, PharmGKB and PharmVar provide clinical guidelines to help physicians to avoid inadequate prescriptions and provide proper dosages. Integrating pharmacogenomic testing into routine medical practice becomes more and more essential. Doing so will enhance patient safety, support personalized medicine and ensure effective and save treatment for everyone
Raising resilience through mentorship – evaluation of a high school program for prevention of peer violence from the perspective of student mentors
No full textOvaj rad istražuje iskustva učenica srednje škole koje su sudjelovale u programu vršnjačkog mentorstva u sklopu projekta „Snažni(ji) zajedno – vršnjačkim mentorstvom do okruženja bez nasilja“. Cilj istraživanja bio je ispitati njihov osobni doživljaj uloge vršnjačke mentorice te proučiti doprinos programa njihovom osobnom razvoju i razvoju otpornosti. Kvalitativna metodologija s polustrukturiranim intervjuima omogućila je dubinsku analizu motiva, izazova i koristi koje su sudionice prepoznale u svom iskustvu. Rezultati pokazuju kako program potiče razvoj komunikacijskih i emocionalnih vještina, jača samopouzdanje te doprinosi boljem nošenju sa stresom i izazovnim životnim situacijama. Sudjelovanje u programu povezano je s osjećajem svrhe, pripadnosti i stvaranjem podržavajuće zajednice, što su ključni elementi otpornosti. Istraživanje ističe transformativni potencijal vršnjačkog mentorstva te njegovu vrijednost u prevenciji vršnjačkog nasilja, pri čemu se program pokazao usklađenim s nacionalnim i međunarodnim preporukama za razvoj sigurnog i podržavajućeg školskog okruženja.This thesis explores the experiences of high school girls participating as peer mentors in the project “Stronger together – creating a violence-free environment through peer mentorship.” The study aimed to examine their subjective experience of the mentoring role and explore the program’s contribution to their personal development and the development of resilience. A qualitative approach using semi-structured interviews enabled an in-depth analysis of participants’ motivations, challenges, and perceived benefits. Findings indicate that the program fosters the development of communication and emotional skills, enhances self-confidence, and supports more effective coping with stress and life challenges. Participation was linked to a sense of purpose, belonging, and the formation of a supportive community—key elements of resilience. The research highlights the transformative potential of peer mentorship and its value in the prevention of peer violence. The program aligns with both national and international recommendations for creating safe and supportive school environments