23 results on '"Tadić, Andrea"'
Search Results
2. Coastal vulnerability and flooding of settlements due to sea level rise
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Tadić, Andrea, primary, Ružić, Igor, additional, Benac, Čedomir, additional, Krvavica, Nino, additional, Jakupović, Dado, additional, Ljubičić, Gorana, additional, and Petrović, Vedrana, additional
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- 2023
- Full Text
- View/download PDF
3. Large gravitational collapse structure on a rocky coast (Kvarner, NE Adriatic Sea)
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Benac, Čedomir, Dugonjić Jovančević, Sanja, Navratil, Dražen, Tadić, Andrea, Maglić, Lovro, Benac, Čedomir, Dugonjić Jovančević, Sanja, Navratil, Dražen, Tadić, Andrea, and Maglić, Lovro
- Abstract
The studied rock collapse structure is located on the Liburnian coast (Rijeka Bay, channel zone of the NE Adriatic). The relief of the southern part of this coast, with a length of 6.5 km, is a large escarpment with very steep to vertical slopes reaching heights of 100 m above sea level, as a result of tectonic movements along the Kvarner fault zone. These events probably led to a sudden relaxation of the highly fractured rock mass. The progressive expansion occurred at locations where previously favourably oriented faults and fissures had formed a polygonal rock collapse resembling a rock-slide which is the focus of this study. Another aim of this study is to reconstruct and explain the complex morphological evolution of the studied landslide, from the pre-failure deformations, through the failure itself, to post-failure displacements, as well as possible future instabilities. Recent techniques to survey the instability, location and to analyse the evolution of the rupture surface and its dimensions were combined (Unmanned Aerial Vehicle, Side Scan Sonar and Remotely Operated Vehicles). The estimated total volume of displaced rock mass is 950,000 m3. The lower part of the instability phenomenon was submerged during the Holocene sea level rise. Since then, a large part of the displaced rock mass has been in a stable position, with sporadic rock falls. However, given unfavourable orientation and discontinuity characteristics, as well as unfavourable environmental influences, possible instabilities might also be expected in the future.
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- 2023
4. The role of gravel pocket beach on stability of urban rocky coastline
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Ružić, Igor, Tadić, Andrea, Ilić, Suzana, Krvavica, Nino, Benac, Čedomir, Strypsteen, G., Roest, B., Bonte, D., and Rauwoens, P.
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gravel beach, coastal cliff, erosion ,coastal cliff ,gravel beach ,erosion - Abstract
Gravel beaches provide natural coastal protection along other ecosystem services to many coastal areas. By dissipating wave energy, they can contribute to stability of cliffs and coastal structures behind them. This paper investigates the effectiveness of gravel pocket beaches (GPB) for protecting urban coastline in the city of Rijeka, Croatia. Two beach systems were studied, a natural system comprised of a beach and a cliff (Sablićevo) and a man-made system (Ploče) comprised of an artificial beach and a sea wall. The rocky coastline around Rijeka is predominantly formed in carbonates (Benac et al., 2013). A number of pocket gravel beaches can be found at locations of previously weakened carbonates, where a local erosion of coastal cliffs provides the sediment supply (Pikelj and Juračić, 2013). This is a micro-tidal environment with a tidal range between 20 and 50 cm. The coastline is exposed to wind-generated waves from the south-east (SE) to south-west (SW) directions, with the largest significant wave height of 3 m in the Rijeka Bay (Lončar et al., 2014). The highest waves from the SE direction are usually accompanied by storm surges. The heights water elevation of 1.27 m CVD was recorded at the nearby tidal gauge in Bakar Bay, east of Rijeka, on 29th October 2018.
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- 2022
- Full Text
- View/download PDF
5. Post-Nourishment Changes of an Artificial Gravel Pocket Beach Using UAV Imagery
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Tadić, Andrea, Ružić, Igor, Krvavica, Nino, Ilić, Suzana, Tadić, Andrea, Ružić, Igor, Krvavica, Nino, and Ilić, Suzana
- Abstract
Monitoring and analysis of changes in the volume and area of nourished beaches is crucial to inform any beach renourishment programme. The aim of this study is to utilise UAV surveys and SfM photogrammetry to assess the beach nourishment performance of an artificial gravel beach exposed to a range of external forcing, including storms. The paper presents results from nineteen UAV surveys conducted between January 2020 and January 2021 at Ploče, an artificial beach in Rijeka (Croatia). The beach was nourished twice and eleven storm events, ranging from weak to strong, were recorded during this period. The Agisoft Metashape software was used to obtain point clouds and digital elevation models (DEM) from UAV images; Matlab and CloudCompare were used for further analysis of the DEMs. The accuracy and precision of the DEMs was assessed and uncertainty levels of ±5 cm were applied to all derived DEMs. The study provides new insights into the response of the emerged part of the beach to storms. Predictably, the largest changes were recorded after the first storm following beach nourishment. The longshore variability in the beach response to storms was identified from full 3D point clouds. Most of the lost sediment was from the east side of the beach, while the rest of the beach aligned with the predominant wave direction through cross-shore and longshore processes. Offshore/onshore sediment exchange between the lower and upper beach face on the western side manifested itself in beach profile steepening and berm formations. Overall, changes in beach volume and area were small, indicating that this artificial beach is relatively stable. The embayed layout following the natural coastal configuration appears to be effective in retaining nourished sediment on the beach. This work highlights the need to consider pocket embayed beaches in three dimensions, as traditional transect studies can overlook the three-dimensional behaviour. This study also highlighted the wider potential
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- 2022
6. Produbljivanje morskog dna za potrebe izgradnje LNG terminala na otoku Krku
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Matešić, Leo, Benac, Čedomir, Prcela, Josip, Tadić, Andrea, Matešić, Leo, Benac, Čedomir, Prcela, Josip, and Tadić, Andrea
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Kod Omišlja na otoku Krku, gdje je predviđena izgradnja pristaništa za ukapljeni plin, hidrografskim mjerenjima ustanovljene su tri pličine na dubinama 13,5 i 13,6 m. Zbog sigurnosti plovidbe, morsko dno je moralo biti dublje od 15,4 m. Pomoću hidroakustičkih metoda istraživanja i autonomne ronilice ustanovljena je geološka građa morskog dna. Pličine su oblikovane u čvrstoj karbonatnoj stijenskoj masi. Primijenjena je posebna tehnologija iskopa bez miniranja. Iskopano je 11.000 m3 stijenske mase koja je deponirana u blizini. Izmijenjeno je stanište površine oko 12.500 m2., Near Omišalj on the island of Krk, where the construction of a pier for liquefied gas is planned, hydrographic measurements revealed three shoals at depths of 13.5 and 13.6 metres. For the safety of navigation, the seabed had to be deeper than 15.4 m. The geological fabric of the seabed was determined using a hydroacoustic survey and remote operating vehicle. Shallows are formed in a solid carbonate rock mass. Special technology of excavation without blasting was applied. 11,000 m3 of rock mass was excavated which was deposited nearby. The seabed habitat with an area of about 12,500 m2 was changed.
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- 2022
7. Post-Nourishment Changes of an Artificial Gravel Pocket Beach Using UAV Imagery
- Author
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Tadić, Andrea, primary, Ružić, Igor, additional, Krvavica, Nino, additional, and Ilić, Suzana, additional
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- 2022
- Full Text
- View/download PDF
8. Analiza ranjivosti obalnog pojasa Primorsko-goranske županije zbog podizanja razine mora
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Ružić, Igor, Benac, Čedomir, Tadić, Andrea, Krvavica, Nino, Petrović, Vedrana, Ljubičić, Gorana, and Jakupović, Dado
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obala, ranjivost, podizanje razine mora, Jadransko more - Abstract
Analizirana je ranjivost obala Primorsko –goranske županije čija je ukupna duljina 1.072 km. Određivanje indeksa ranjivosti obale (CVI) izvršeno je za segmente obale duljine 25 m, a na temelju pet odabranih parametara (varijabli): geološke građe, obalnog nagiba, značajne visine valova, izloženosti plavljenju te postojanja i utjecaja žala. Prikazani rezultati analiza ranjivosti obala pokazali su složenost istraživanog područja, sa značajnim varijacijama indeksa ranjivosti duž obala. Ispitani su i scenariji plavljenja za prognozirani porast morske razine za 60 cm do kraja stoljeća, odnosno 120 cm kod ekstremnih plima. Potvrđena je visoka ranjivost obalnih naselja, prvenstveno zbog izloženosti plavljenju. Pokazalo se da je potrebno stvoriti baze podataka na temelju dovoljno točnih podataka o reljefu kopna i podmorja, geološkoj građi i oceanografskim značajkama, kako bi se mogao odrediti stupanj ranjivosti te mjere umanjenja hazarda i rizika.
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- 2022
9. Deepening of the seabed for the construction of the LNG terminal on the island of Krk
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Matešić, Leo, Benac, Čedomir, Prcela, Josip, and Tadić, Andrea
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morsko dno, iskop, nasipavanje, karbonatna stijena, Riječki zaljev, Jadransko more ,seabed, excavation, fill, carbonate rock, Rijeka Bay, Adriatic Sea - Abstract
Kod Omišlja na otoku Krku, gdje je predviđena izgradnja pristaništa za ukapljeni plin, hidrografskim mjerenjima ustanovljene su tri pličine na dubinama 13,5 i 13,6 m. Zbog sigurnosti plovidbe, morsko dno je moralo biti dublje od 15,4 m. Pomoću hidroakustičkih metoda istraživanja i autonomne ronilice ustanovljena je geološka građa morskog dna. Pličine su oblikovane u čvrstoj karbonatnoj stijenskoj masi. Primijenjena je posebna tehnologija iskopa bez miniranja. Iskopano je 11.000 m3 stijenske mase koja je deponirana u blizini. Izmijenjeno je stanište površine oko 12.500 m2., Near Omišalj on the island of Krk, where the construction of a pier for liquefied gas is planned, hydrographic measurements revealed three shoals at depths of 13.5 and 13.6 metres. For the safety of navigation, the seabed had to be deeper than 15.4 m. The geological fabric of the seabed was determined using a hydroacoustic survey and remote operating vehicle. Shallows are formed in a solid carbonate rock mass. Special technology of excavation without blasting was applied. 11,000 m3 of rock mass was excavated which was deposited nearby. The seabed habitat with an area of about 12,500 m2 was changed.
- Published
- 2022
10. Primjena trodimenzionalnih oblaka točaka za monitoring morfoloških promjena plaže
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Ružić, Igor, Tadić, Andrea, Salopek, Marinko, Racetin, Ivana, Zrinjsk, Mladen, and Župan, Robert
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bespilotna letjelica, promjene plaže, SfM fotogrametrija, trodimenzionalni oblak točaka, umjetna plaža - Abstract
U ovom je radu opisana primjena trodimenzionalnih oblaka točaka, generiranih iz fotografija snimljenih dvjema bespilotnim letjelicama: Matrice 600 Pro s kamerom Sony ILCE-7M2 i Phantom 4 Pro. Za potrebe projekta Održiva gradnja plaža – gradnja novih i povećanje kapaciteta postojećih plaža (Beachex) provedeno je ukupno 19 letova tijekom 2020. i 2021. godine na plaži Ploče (Kantrida, Rijeka). Gustoća oblaka točaka dobivenih fotogrametrijskim postupkom u prosjeku je 5.670 točaka po m², a točnosti na kontrolnim točkama za sva su snimanja oko 5 cm. Rezultati točnosti i preciznosti pokazuju da nema značajne razlike između oblaka točaka snimljenih dvjema letjelicama. Slabije performanse Phantoma 4 kompenzirane su nižom visinom i dužim trajanjem leta i većim brojem fotografija. Konzervativna vrijednost točnosti od ± 5 cm usvojena je za procjenu određenih parametara plaže. Oblaci točaka pokazali su se kao vrijedan ulazni podatak pri analizama promjena plaža. Prvenstveno je moguće pratiti visinske promjene žala između uzastopnih mjerenja, koje su na plaži Ploče značajno veće od postignute preciznosti oblaka točaka. Transport materijala unutar promatranog područja može se točno prostorno definirati uz pomoć trodimenzionalnih podloga, a vrlo precizno može se pratiti i pomak obalne linije. Analizirane su i promjene površine i volumena tijela plaže, ali zbog relativno malih varijacija ovih parametara između snimanja, moguće je pratiti samo trend njihovih promjena. Za određivanje točne količine materijala ipak će biti potrebno raspolagati s preciznijim podlogama.
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- 2022
11. FENOLNI PROFIL I BIOLOŠKI POTENCIJAL NUSPROIZVODA VINIFIKACIJE BIJELOG VINA
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Tadić, Andrea
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vinski talog, nusproizvodi, fenoli, HPLC, antioksidacijska aktivnost - Abstract
Preradom grožđa i postupkom vinifikacije zaostaju vrijedni nusproizvodi sa visokim sadržajem fenola koji posjeduju brojna pozitivna biološka svojstva, osobito antioksidacijsku i antimikrobnu aktivnost. Nusproizvod kao što je vinski talog pokazao se bogatim izvorom vlakana i fenola što omogućava njegovo korištenje u prehrani. U ovom radu su ispitana dva uzorka taloga prikupljena tijekom proizvodnje bijelog vina, nakon maceracije i prije fermentacije te nakon provedene hladne fermentacije. Određeni su ukupni fenoli metodom po Folin-Ciocalteu, fenolni profil HPLC (eng. High performance liquid chromatography) metodom te je ispitana antioksidacijska aktivnost FRAP (eng. Ferric reducing antioxidant power), ORAC (eng. Oxygen radical apsorbance capacity) i DPPH (eng. 2, 2-diphenyl-1-picrylhydrazyl free radical scavenging) metodom. Rezultati ispitivanja pokazuju izuzetno visok udio fenola te raznolik fenolni profil ekstrakata. Osim fenolnog sastava uzorci su pokazali i dobru antioksidacijsku aktivnost. Iako su oba uzorka imala iznenađujuće dobre rezultate, posebno se ističe talog bijelog vina nakon maceracije obzirom da je imao gotovo dvostruko veći udio fenola kao i dvostruko bolju antioksidacijsku aktivnost u odnosu na talog vina uzorkovan nakon provedene fermentacije.
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- 2022
12. Ranjivost obalnoga područja Primorsko-goranske županije zbog klimatskih promjena
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Ružić, Igor, Benac, Čedomir, Tadić, Andrea, Krvavica, Nino, Petrović, Vedrana, Ljubičić, Gorana, Jakupović, Dado, and Lakušić, Stjepan
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klimatske promjene, rast razine mora, indeks obalne ranjivosti, marinska erozija, rizik, Kvarner - Abstract
U ovome radu prezentirani su rezultati istraživanja obalne ranjivosti Primorsko-goranske županije (PGŽ). Istraživanje je provedeno u suradnji s Javnom ustanovom Zavod za prostorno uređenje Primorsko-goranske županije. Rezultati istraživanja koristit će se kao podloga za izradu prostorno-planske dokumentacije. Razvijena je metodologija istraživanja obalne ranjivosti koja je prilagođena specifičnim karakteristikama obale Republike Hrvatske. Indeks ranjivosti obale (CVI) određen je za segmente obale duljine 25 m, i to na temelju pet odabranih parametara (varijabli): geološke građe, obalnoga nagiba, znatne visine valova, izloženosti plavljenju te postojanja i utjecaja žala. Analize su provedene za čitavu obalu PGŽ-a, čija ukupna dužina obalne linije iznosi 1235 km. Prikazani rezultati analiza ranjivosti obala pokazali su složenost istraživanoga područja te znatne varijacije indeksa ranjivosti duž obale. Ispitani su i scenariji ranjivosti s težištem na plavljenju obalnoga područja za prognozirani porast morske razine za 60 cm do kraja stoljeća, odnosno za 120 cm prilikom ekstremnih plima. Pokazalo se to da je potrebno stvoriti baze podataka na temelju dovoljno točnih podataka o reljefu kopna i podmorja, geološkoj građi i oceanografskim značajkama kako bi se mogli odrediti stupanj ranjivosti te mjere umanjenja rizika.
- Published
- 2021
13. Analiza plavljenja područja napuštene šljunčare Kikovica
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Ružić, Igor, Krvavica, Nino, and Tadić, Andrea
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šljunak, plavljenje, iskop, razina vode, podzemne vode - Abstract
U radu je analizirano plavljenje napuštene šljunčare Kikovica na osnovi provedenih mjerenja površinskih i podzemnih voda. Utvrđeno je da dolazi do značajnih plavljenja analizirane retencije. Preporuča se provesti sanacija napuštene šljunčare sukladno važećoj legislativi i praksi.
- Published
- 2021
14. Vulnerabilität der Küste der Insel Krk
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Benac, Čedomir, Tadić, Andrea, Petrović, Vedrana, Jakupović, Dado, Ljubičić, Gorana, Krvavica, Nino, and Ružić, Igor
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klimatske promjene ,rast razine mora ,indeks obalne ranjivosti ,marinska erozija ,prirodni hazard ,rizik ,Kvarner ,Jadransko more ,klimatske promjene, rast razine mora ,climate change ,sea level rise ,coastal vulnerability index ,marine erosion ,natural hazard ,risk ,Kvarner area ,Adriatic Sea ,Klimawendel ,Meeresspiegelanstieg ,Vulnerabilitätsindex für die Küste ,Meereserosion ,natürliche Gefahr ,Risiko ,Adria - Abstract
U ovom radu analizirana je ranjivost obala otoka Krka. Određivanje indeksa ranjivosti obale (CVI) izvršeno je za segmente obale duljine 25 m, a na temelju pet odabranih parametara (varijabli): geološke građe, obalnog nagiba, značajne visine valova, izloženosti plavljenju te postojanja i utjecaja žala. Prikazani rezultati analiza ranjivosti obala pokazali su složenost istraživanog područja, sa značajnim varijacijama indeksa ranjivosti duž obale otoka. Ispitani su i scenariji plavljenja za prognozirani porast morske razine za 60 cm do kraja stoljeća, odnosno 120 cm kod ekstremnih plima. Potvrđena je visoka ranjivost obalnih naselja na otoku Krku, prvenstveno zbog izloženosti plavljenju. Pokazalo se da je potrebno stvoriti baze podataka na temelju dovoljno točnih podataka o reljefu kopna i podmorja, geološkoj građi i oceanografskim značajkama, kako bi se mogao odrediti stupanj ranjivosti te mjere umanjenja hazarda i rizika., The paper provides analyses of the Krk Island coast vulnerability. The determination of the coastal vulnerability index (CVI) was carried out for costal segments of 25 m in length and based on 5 selected parameters (variables): geological composition, fabric coastal slope, significant wave heights, exposure to flooding, and the existence and impact of shores. The presented results of the costal vulnerability analyses revealed the complexity of the researched area, with significant variations of the vulnerability index along the island’s coast. Flooding scenarios for the forecast increase in sea levels by 60 cm until the end of the century, i.e. 120 cm at extreme tides were also tested. High vulnerability of the costal settlements on Krk Island was confirmed, primarily due to flooding exposure. It is necessary to create databases with sufficient accurate data on land and seafloor relief, geological composition fabric and oceanographic characteristics to determine the degree of vulnerability and hazard and risk mitigation measures., n diesem Beitrag wird die Vulnerabilität der Küste der Insel Krk analysiert. Der Vulnerabilitätsindex (engl. coastal vulnerability index; CVI) wurde für die Küstensegmente in Länge von 25 m bestimmt und zwar aufgrund der fünf Variablen: geologischer Aufbau, Küstengefälle, signifikante Wellenhöhe, Anfälligkeit gegenüber Überschwemmung und Existenz und Auswirkung des Strandes. Die dargestellten Ergebnisse der Analyse der Küstenvulnerabilität zeigen, dass das Forschungsgebiet einschließlicherheblicher Variationen des Vulnerabilitätsindexes entlang der Inselküsten komplex ist. Die Überschwemmungsszenarien für einen Meeresspiegelanstieg von 60 cm bis Ende des Jahrhunderts bzw. 120 cm bei extrem hohen Flut wurden auch simuliert. Die sehr hohe Vulnerabilität der Küstensiedlungen auf der Insel Krk wurde bestätigt, insbesondere weil sie Überschwemmungen ausgesetzt sind. Es hat sich auch gezeigt, dass Datenbanken aufgrund richtiger Angaben über Land- und Meeresrelief, geologischen Aufbau und ozeanographische Merkmale erstellt werden sollen, um den Vulnerabilitätsgrad und die Maßnahmen bestimmen zu können undsomit Gefahr und Risiko zu reduzieren.
- Published
- 2021
15. The application of remote sensing for monitoring the morphological changes of Ploče beach in Rijeka
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Tadić, Andrea, Grbčić, Ana, Lopac, Nikola, Strabić, Marko, Dugonjić Jovančević, Sanja, Franulović, Marina, and Vukelić, Goran
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beach erosion ,SfM photogrammetry ,point cloud ,digital elevation model - Abstract
Unmanned aerial vehicles (UAVs) have been used for coastal research in Croatia since 2012. SfM-MVS photogrammetry is mostly used for analysis of changes on beaches, which increasingly requires high resolution and precision of three-dimensional point clouds resulting from photogrammetric technique [1]. In this paper, this technology was used to study coastal processes on Ploče beach in Rijeka. The beach was surveyed 19 times with a drone in 2020 and 2021, and two 3D scans of the beach area were performed to determine the accuracy of the point clouds. The defined point cloud precision for the emerged beach is better than ± 5 cm. The point cloud representing the submerged beach was compared to the multibeam echo sounder data, and the results showed significantly greater discrepancies than for the emerged beach. The accuracy of the submerged point cloud data was increased by depth correction using the light refractive index, but more accurate corrections are one of the ultimate goals of this research. The CloudCompare software has also proven to be a useful tool for identifying and describing beach surface changes. Successive beach surveys were compared and digital models of the differences (DoDs) were created as a result. The comparisons showed that the greatest changes on the beach are caused by waves from southern and southeastern directions, and when storm events are accompanied by higher rainfall, runoff from coastal springs enhances the coastal process on the beach body. UAV photogrammetry has proven to be a simple, fast, and cost-effective tool for describing and visualising changes on beaches, considering that the morphological changes under the influence of waves and precipitation are much greater than the accuracy achieved.
- Published
- 2021
16. Erozija žala plaže Ploče (Rijeka)
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Tadić, Andrea
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erozija šljunčanih plaža ,digitalni model terena ,SfM fotogrametrija ,CloudCompare ,Shingle model - Abstract
Osnovni problem koji se javlja na šljunčanim plažama svakako je erozija izazvana vjetrovnim valovima. U Hrvatskoj, zahvaljujući turističkoj potražnji, sustavni monitoring obale postaje važan dio upravljanja priobalnim područjima, kako bi održavanje oblika i povećanje kapaciteta plaža bilo opravdano i efikasno. U te svrhe izrađuju se digitalni visinski modeli ispitivanih područja, a kao jeftina, brza i jednostavna metoda za prikupljanje podataka sve više se koristi SfM (eng. Structure from Motion) fotogrametrija. Ova tehnologija omogućuje izradu trodimenzionalnih oblaka točaka promatranoga područja, visoke preciznosti i razine detaljnosti iz niza fotografija. U radu je opisana primjena ovoga postupka na istraživanje problema erozije plaže Ploče u Rijeci. Nakon 7 snimanja terena, odgovarajući oblaci točaka uspoređivali su se u CloudCompare-u. Rezultati pokazuju da je plaža u 50 dana nakon dohranjivanja izgubila cca. 50 m³ materijala kao rezultat valne aktivnosti tijekom i nakon snažnih vjetrova iz smjera juga. Na istočnoj ćeliji plaže gdje je izraženo pomicanje materijala okomito na obalnu liniju izvršena je i usporedba oblika plaže s teoretskim Shingle modelom.
- Published
- 2020
17. Proračun konstrukcija prema teoriji plastičnosti
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Tadić, Andrea
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teorija plastičnosti, Prandtlov model, granica tečenja, plastični zglob - Abstract
U radu je detaljno obrađen proračun konstrukcija prema teoriji plastičnosti, odnosno proračunu prema graničnim stanjima. U uvodnom dijelu opisane su glavne postavke u odnosu na teoriju elastičnosti, a u nastavku je opisan model i svojstva materijala za koji se ovakav proračun može provesti. Proračun je prikazan na primjeru ravnoga štapa opterećenoga na čisto savijanje i savijanje silama, te je objašnjen način otkazivanja. Također su navedene metode proračuna statički neodređenih konstrukcija. Riješen je kvalitativan primjer te su opisani statički i kinematički teorem na kojima se proračun ovakvih konstrukcija i temelji. Na kraju rada dana su dva numerička primjera proračuna statički neodređenih konstrukcija.
- Published
- 2018
18. The Role of Picturebooks in Helping Children Become Autonomous Readers
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Tadić, Andrea
- Subjects
the Croatian National Curriculum ,teaching reading ,picturebook ,scaffolding ,autonomous readers ,David Shannon - Abstract
As stated in the Croatian National Curriculum one of the main goals of teaching reading skills in a foreign language context is to form positive attitudes towards the language in question (English in this case), and to select and read various types of texts, either with the help of others or independently (2010, p. 54). This thesis takes into account the strategy of scaffolding as a necessary tool in the problem-solving approach to teaching literature. Contemporary picturebooks, as the most suitable type of literature for lower primary grades, prove to be an efficient medium for the transition from illiteracy to literacy and, more importantly, for the scaffolded development of autonomous readers. The thesis emphasizes the double communication in picturebooks, dependent on its parallel discourses, visual and verbal, that encourages readers to use higher literacy skills. Several picturebooks by David Shannon are analysed in this context, and activities are developed based on the picturebook David Goes to School (1999) to support child-readers on their way towards becoming independent readers.
- Published
- 2016
19. The Story of Alice: Lewis Carroll and the Secret History of Wonderland.
- Author
-
Tadić, Andrea
- Subjects
NONFICTION - Published
- 2015
20. Preliminary analyses of the optimal distance between a roundabout and signalized intersection
- Author
-
Klobučar, Mirna, Deluka-Tibljaš, Aleksandra, Dugonjić Jovančević, Sanja, Sulovsky, Tea, and Tadić, Andrea
- Subjects
delay, minimum distance, roundabout, signalized intersection, VISSIM - Abstract
With increasing urban traffic flows and increased congestions, the question of design modifications and intersection reconstruction is a common problem for urban traffic designers. Roundabouts are often chosen when planning new intersections and reconstructing old ones, given numerous advantages in terms of traffic safety and lower maintenance costs. When planning roundabouts, in addition to micro-location, it is important to consider functional criteria and the influence of adjacent intersections. Usually, roundabouts experience less queuing than signalized intersections. The queues for the signals will govern and, in the case of a more significant amount of traffic, have a negative impact on roundabout capacity. In the literature, it is emphasized that the positioning of a roundabout between two adjacent signalized intersections should be avoided. Still, in practice, it is not always possible to prevent this situation. There are no specific guidelines for the acceptable distance between signalized intersection and roundabout. Traffic queues that extend into adjacent intersections need to be analyzed further. The design of the system generally follows the principles of isolated roundabout design, but modeling requires two steps. The first step is providing a model as an isolated intersection – deterministic models. The second, often overlooked, step is analyzing the model as a system – stochastic model. The research utilized the well-known software package VISSIM to evaluate the performance of signalized intersections and roundabouts, respectively. Four-leg intersections at different distances were taken into account. A microsimulation analysis was performed to determine the minimum distance at which a nearby signalized intersection does not affect the traffic flow of the roundabout.
- Published
- 2022
21. DIC-based experimental analysis of plate specimens with central holes loaded in tension
- Author
-
Bjelobradić, Sanja, Basan, Robert, Marković, Ela, Marohnić, Tea, Dugonjić Jovančević, Sanja, Sulovsky, Tea, and Tadić, Andrea
- Subjects
Digital Image Correlation (DIC) ,Plate with central hole ,Stress concentrator ,Experiment - Abstract
Digital Image Correlation (DIC) experimental method is receiving a significant attention recently both in research and industry since it enables full-field, non-contact optical measurements of deformations and strains on almost any material and any geometry [1, 2]. In this study, DIC measurement system was used for determination and analysis of the values of strains and stresses in plate specimens with central hole loaded elastically in tension using a tensile testing machine. In order to determine the applicability of the method and the sizes of geometrical discontinuities i.e., stress concentrators that can be successfully characterized with available equipment, plate specimens made of various materials and with central holes of different sizes were studied. An important step in preparation of the specimens, which can have significant influence on results, is creation of the appropriate random speckle pattern on the specimen’s surface which is usually done by spraying paint [3]. In this work, speckle pattern was applied using airbrush system and influence of speckle pattern on measurement results was considered. Values of strains and stresses on individual specimens were determined using basic empirical equations, numerically with the FEA software and compared with those determined experimentally using the DIC system. Results of the study are reported.
- Published
- 2022
22. On the overset grids in computational Marine Hydrodynamics
- Author
-
Sulovsky, Ivan, Prpić-Oršić, Jasna, Dugonjić Jovančević, Sanja, Sulovsky, Tea, and Tadić, Andrea
- Subjects
CFD, marine hydrodynamics, seakeeping, onboard measurements - Abstract
An overview of using overset grids in computational marine hydrodynamics is presented. The main advantage of this method is the ability to capture large rigid body displacements that a ship withstands during voyage. Two different cases are presented in which overset grids are appropriate, using open source CFD toolkit OpenFOAM® [1]. First example includes wave response of a container ship scale model in regular steep waves. Results agree well with the experiment [2] which confirms the superiority of fully viscous CFD solvers for seakeeping problems. Second case is intrinsically different: open water propeller characteristics are calculated where rotating motion and advance speed are apriori known. Thrust and moment values are derived from the numerical simulation, showing good agreement with KT and KQ coefficients obtained by experiment [2]. Without any constraints in terms of motions, overset technique offers a powerful tool in numerical marine hydrodynamics despite having higher computational costs. Given the presented possibilities of overset, further work is revealed. With the possibility to validate the numerics with data from onboard measurements of a real going ship [4], expected investigations in terms of speed loss, propulsion efficiency etc. using high fidelity CFD tools are discussed.
- Published
- 2022
23. Application of feature selection techniques in assessing variables relevant for estimation of materials parameters and behavior
- Author
-
Marković, Ela, Marohnić, Tea, Basan, Robert, Dugonjić Jovančević, Sanja, Sulovsky, Tea, and Tadić, Andrea
- Subjects
Material behavior ,Cyclic/fatigue parameters ,Feature engineering/selection - Abstract
To adequately design a structure or a part, the behavior of a material, more precisely, relation between its stresses and strains, must be known. Considering that the experimental determination of fatigue and cyclic material parameters is costly and long-lasting, as opposed to monotonic tensile tests, it is of great interest to use more easily obtainable monotonic properties to estimate cyclic and fatigue material behavior [1]. Building a predictive model from acquired data can be done using classical approaches, such as regression, or more recently, various available machine learning methods. The dataset which is used as an input for such models needs to be of appropriate size and have an adequate number of input variables, also called predictors, to avoid underfitting or overfitting a model. Higher ratio of number of samples to number of predictors makes the model less likely to be affected by possible errors in data and to generalize new cases well [2]. To increase the data volume, additional datasets can be acquired by performing experiments which take a great amount of time. Therefore, it is more economical to implement a feature selection (i.e. feature engineering) techniques instead, which enable the detection of redundant input variables followed by their removal which then consequently reduces model complexity [2]. In this study, using several chosen feature selection techniques, importance of each predictor in relation with the response is determined and a subset of the most relevant variables for predicting the cyclic and fatigue parameters is selected. Building models with newly acquired subset should reduce overfitting, improve interpretability and decrease the complexity of the model.
- Published
- 2022
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