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LABORATORIJSKO ISPITIVANJE UČINKOVITOSTI DVOKOMPONENTNE SMJESE ZA INJEKTIRANJE IZA SEGMENTA TUNELA U PJESKOVITIM TLIMA ISPOD RAZINE PODZEMNE VODE
No full textThe increasing use of TBMs in urban areas has heightened the significance of grouting behind tunnel segments. A key aspect of mechanized tunnelling is the application of grout for injection behind the tunnel segments (support system) to prevent ground settlement. This study aims to investigate the extent of two-component grout washout behind the segments and also simulates the presence of water flow in laboratory tests, which distinguishes it from other studies. Issues such as groundwater seepage and grout washout behind the segments—particularly when there are failures in the brush (caused by factors like reduced tail thickness from friction with the segment ring, misalignment in the shield from improper assembly, or damage to articulation jacks)—can lead to incomplete filling of the space and cause surface settlements. As a result, selecting an appropriate grout mixing design under these conditions is critical. A study was conducted to assess the injection of two-component grout with varying amounts of bentonite and sodium silicate. Different injection pressures and water conditions were simulated to evaluate grout penetration in coarse-grained soils. The grout injection tests at pressures of 1 and 2 bars showed that increasing the bentonite and sodium silicate in the grout mix not only reduces penetration into the soil but also helps prevent washout due to water flow. It is important to note that sodium silicate has a greater effect on this process than bentonite.Sve veća uporaba TBM-a u urbanim područjima povećala je važnost injektiranja iza tunelskih segmenata. Ključni koncept strojnoga iskopa tunela jest primjena smjese za injektiranje iza segmenata tunela (potporni sustav) kako bi se spriječilo slijeganje tla. Cilj je ove studije istražiti veličinu ispiranja dvokomponentne smjese iza segmenata tunela. Ova studija također simulira prisutnost protoka vode u laboratorijskim testovima, što je razlikuje od drugih sličnih studija. Problemi kao što su curenje podzemne vode i ispiranje smjese iza segmenata tunela, posebice kada postoje nedostatci na četki za brtvljenje (uzrokovani raznim čimbenicima kao što su smanjena debljina dodira zbog trenja o segmentni prsten, neusklađenost štita zbog nepravilnoga sastavljanja ili oštećenja zglobnih potiskivača), mogu dovesti do nepotpunoga ispunjavanja prostora i uzrokovati površinsko slijeganje. Zbog toga je iznimno važno odabrati odgovarajuću smjesu za injektiranje u tim uvjetima. Studija provodi procjenu injektiranja dvokomponentne smjese s različitim količinama bentonita i natrijeva silikata. Simulirani su različiti pritisci injektiranja i vodonosni uvjeti kako bi se procijenilo prodiranje smjese u krupnozrnata tla. Ispitivanja injektiranja smjese za injektiranje pri tlaku od 1 i 2 bara pokazala su da povećanje sadržaja bentonita i natrijeva silikata u smjesi za injektiranje ne samo da smanjuje prodiranje u tlo, već i pomaže u sprječavanju ispiranja smjese uslijed protoka vode. Osim toga, važno je napomenuti da natrijev silikat ima veći učinak na spomenute procese od bentonita
Prevođenje za djecu: odgovornost, dijalog i uloga prevoditelja
No full textTranslators occupy a privileged position when translating works written for a young audience as they are simultaneously ideal readers and authors of the target texts. The apparently easy task of translating children’s literature relies on the translator’s responsibility to keep the author of the source text and the readership in mind. If we consider children’s literature as an opportunity for young readers to shape their own image of the world and – with reference to youth literature – reflect on their identity, translations can nurture a silent dialogue between the reader and the book during reading. This paper outlines the position of children’s literature in academia and the shared multidisciplinary dimension with translation in order to discuss the value of translations and the role of translators as responsible for nurturing a narrative dialogue with young readers.Prevoditelji zauzimaju privilegiranu poziciju pri prevođenju djela namijenjenih mladoj publici jer su istodobno idealni čitatelji i autori ciljanoga teksta. Naizgled jednostavan
zadatak prevođenja u dječjoj književnosti oslanja se na odgovornost prevoditelja da pritom ima na umu i autora izvornoga teksta i ciljnu čitateljsku publiku. Ako dječju književnost promatramo kao mogućnost za mlade čitatelje da oblikuju vlastitu sliku svijeta i – s obzirom na književnost za mlade – promisle o vlastitom identitetu, prijevodi mogu potaknuti tihi dijalog koji se odvija između čitatelja i knjige tijekom čitanja. Ovaj rad iznosi pregled položaja dječje književnosti unutar akademske zajednice te njezine zajedničke multidisciplinarne povezanosti s prevođenjem kako bi se raspravila vrijednost književnih prijevoda i uloga prevoditelja kao odgovornih nositelja dijaloga s mladim čitateljima
PROCJENA UČINAKA JAKE GEOMAGNETSKE OLUJE OD 10. DO 11. SVIBNJA 2024. NA GEOMAGNETSKO POLJE I IONOSFERU NAD INDONEZIJSKIM PODRUČJEM
No full textThe severe geomagnetic storm on May 11, 2024, is the largest space weather phenomenon in the 25th solar cycle. This paper presents the impact of that severe geomagnetic storm (Dst = -412 nT) on the geomagnetic field and ionosphere over Indonesia. Additionally, it examines geoelectric disturbances generated during the storm and disruptions to HF radio communication in Indonesia. The study uses geomagnetic field data (HDZ) and ionospheric data (foF2) from Pontianak and Kupang, averaged minutely and hourly. The results indicate that the geomagnetic storm on May 11th, 2024 caused geomagnetic disturbances with ΔH = -471 nT in Pontianak and ΔH = -462 nT in Kupang. These disturbances led to significant geoelectric disturbances around the region with possible induced currents. In the ionosphere, the geomagnetic storm caused negative ionospheric storms during the main phase and positive storms during the recovery phase, as observed in the foF2 data from both stations. These ionospheric storms resulted in foF2 disturbances (ϕ) with values ranging from -30% to 30%, lasting for 180 minutes.Jaka geomagnetska oluja 11. svibnja 2024. najveći je svemirski vremenski fenomen u 25. Sunčevu ciklusu. U ovome radu prikazan je utjecaj te jake geomagnetske oluje (Dst = –412 nT) na geomagnetsko polje i ionosferu iznad Indonezije. Dodatno, ispituju se geoelektrični poremećaji nastali tijekom oluje i poremećaji HF radiokomunikacije u Indoneziji. Studija upotrebljava podatke o geomagnetskome polju (HDZ) i podatke o ionosferi (foF2) iz Pontianaka i Kupanga, izračunane u prosjeku po minuti i po satu. Rezultati pokazuju da je geomagnetska oluja 11. svibnja 2024. uzrokovala geomagnetske poremećaje s ΔH = –471 nT u Pontianaku i ΔH = –462 nT u Kupangu. Ti su poremećaji doveli do znatnih geoelektričnih potresa oko regije s mogućim induciranim strujama. U ionosferi je geomagnetska oluja uzrokovala negativne ionosferske oluje tijekom glavne faze i pozitivne oluje tijekom faze oporavka, kao što je primijećeno u foF2 podatcima s obiju postaja. Ove ionosferske oluje rezultirale su poremećajima foF2 (Ø) s vrijednostima u rasponu od –30 % do 30 % u trajanju od 180 minuta
Numerical study of scale effects of viscous roll damping for a container ship
No full textIn this paper, the scale effects on a container ship’s roll motion are investigated by numerical approach. The accuracy of the numerical method is verified by comparing numerical results with experimental data through a grid sensitivity study. The roll decay tests of the vessel at full-scale and model-scale at various forward speeds are simulated, and it is noticed that scale effects on roll motion occur when forward speed is nil or low. To further understand the impacts of scale on damping components, forced roll tests with different forward speeds are simulated, roll damping coefficients are determined, the flow field created by roll motion and forward speed near bilge keels is observed. It is found that the scale effects affect both the frictional and bilge keel damping components. At low Froude number, the difference of the relative velocity distributions for the height (or breadth) of bilge keels between model (model-scale) and ship (full-scale) is proved as the cause of the scale effects on the bilge keel component
Pisma Ivane Brlić-Mažuranić svojim roditeljima
No full textPrikaz knjige "Pisma majci i ocu (1902. – 1928.)" Ivane Brlić-Mažuranić. Knjiga je izdao Ogranak Matice hrvatske u Slavnoskom Brodu 2024. godine
Djeca se igraju kazališta lutaka
No full textPrikaz knjige "Scenska lutka i igra u dječjem vrtiću: Pedagogijski temelji i odgojno-obrazovna praksa" autora Branimira Mendeša i Vlaste Pokrivke. Knjigu je izdala izdavačka kuća Alfa u Zagrebu 2024. godine
Translating Proper Names in the New Testament
No full textU sklopu znanstveno-istraživačkog projekta Egzegetski instrumentarij Novoga zavjeta rad se bavi pitanjem prijevoda imena osoba u Novom zavjetu. Uspoređujući hrvatske novozavjetne prijevode (Šarić, Katančić, Duda i Fućak, Gusič i Rupčić), uočavaju se različiti pristupi, metodologija i načela prevođenja. Rad ne donosi jedan pristup, ne predlaže ujednačenu metodologiju i ne određuje jasna načela prevođenja, niti određuje izvorni tekst kojim su se autori služili pri izradi prijevoda. U skladu s ciljevima projekta u radu se donose ključni statistički podatci o uporabi i učestalosti novozavjetnih vlastitih imena te se ukazuje na neke poteškoće i otvorena pitanja njihova prijevoda kao što su neujednačena transliteracija, ispravci imena (npr. Mt 1,7.10), prijevod istovjetnih oblika imena koje nosi više osoba (npr. Ana, Jakov, Josip), prijevod različitih oblika imena koje nosi ista osoba (npr. Lk 1,27.41), pitanje prevođenja imena ili njegova izvođenja iz izvornog oblika (npr. Dj 9,36a) i poteškoća pri određivanju vlastitih imenica u nominativu jednine (npr. 2 Tim 4,13; Dj 6,5).As part of the scientific-research project Exegetical Instrumentation of the New Testament, the paper addresses the issue of the translation of proper names in the New Testament. Comparing Croatian New Testament translations (Šarić, Katančić, Duda and Fućak, Gusič and Rupčić), different approaches, methodology and translation principles can be observed. The paper does not adopt a single approach, does not propose a uniform methodology and does not define clear principles of translation, nor does it define the original text that the authors had used when they created the translation. In accordance with the objectives of the project, the paper presents the most significant statistical data on the use and frequency of the New Testament proper names and points out some difficulties and open questions in their translation, such as uneven transliteration, corrections of names (e.g. Mt 1:7,10), translation of identical forms of names borne by several people (e.g., Anne, Jacob, Joseph), translation of different forms of names held by the same person (e.g., Lk 1:27,41), the question of translating a name or deriving it from its original form (e.g., Acts 9:36a) and the difficulty of determining proper nouns in the nominative singular (e.g., 2 Tim 4:13; Acts 6:5)
Održivost i čimbenici koji utječu na proizvodnju bakterijske celuloze: pregled utjecaja mikroorganizama, hranjivih podloga i metoda uzgoja
No full textThis review provides a comprehensive analysis of bacterial cellulose production, with a focus on the key factors influencing the bioprocess, including microorganism selection, substrate optimization and cultivation techniques. It addresses the challenges associated with bacterial cellulose production and proposes strategies to optimize upstream processes, such as microorganism preservation, inoculum preparation and culture medium formulation, which are critical for improving production efficiency. Additionally, the review explores the effects of fermentation parameters such as time, temperature, and oxygen availability on the yield and quality of bacterial cellulose. It also highlights the growing interest in utilizing alternative substrates, particularly agro-industrial waste, to reduce production costs and improve sustainability. By evaluating these factors, this review provides valuable insights for the further development of bacterial cellulose production in both research and industrial applications.Pozadina istraživanja. Cvjetovi maslačka imaju vrlo kratak vijek trajanja. Poznato je da proces konzerviranja stabilizira hranu i čuva njezin hranjivi sadržaj u velikoj mjeri, te značajno produljuje njezin vijek trajanja. Iz tog se razloga smatra da konzervirani cvjetovi maslačka mogu biti korisni i za potrošače i za gastronomski sektor.
Eksperimentalni pristup. U ovom su istraživanju svježi cvjetovi maslačka (Taraxacum officinale L.) konzervirani u šećernom sirupu različitih stupnjeva Brixa (20 i 30 °Bx) i skladišteni na 25 °C tijekom 30 dana. Pomoću tekućinske kromatografije spregnute s masenom spektrometrijom (LC-MS/MS) identificirano je ukupno 56 fitokemikalija, dok su aktivnost uklanjanja 2,2-difenil-1-pikrilhidrazil radikala (DPPH) i sposobnost redukcije iona bakra (CUPRAC), kao i ukupni udjel fenolnih spojeva (TPC), analizirani u konzerviranim cvjetovima i sirupu u različitim razdobljima skladištenja (deseti, dvadeseti i trideseti dan).
Rezultati i zaključci. Antioksidacijske aktivnosti svježih cvjetova maslačka iznosile su 89,6 % i 0,8 mmol ekvivalenata Troloksa (TE) po gramu. Najmanje aktivnosti uklanjanja DPPH (41,4 %) i CUPRAC izražene kao ekvivalenti Troloksa (0,3 mmol/g) opažene su dvadeseti dan u uzorcima pohranjenim u sirupu s 30 °Bx. Ukupni udjel polifenola u svježim cvjetovima, izražen kao ekvivalent galne kiseline po gramu ekstrakta, iznosio je 367,4 mg/g. Najveći ukupni udjel polifenola u konzerviranim cvjetovima utvrđen je desetog dana u uzorcima u sirupu s oba °Bx. Analizom LC-MS/MS u svježim su cvjetovima identificirana 24 fitokemijska spoja, uključujući kininsku kiselinu, luteolin, siranosid, klorogensku kiselinu, fumarinsku kiselinu, kafeinsku kiselinu, protokatehuičnu kiselinu, kvercetin, kozmoziin, izokvercitrin i apigenin. Tijekom skladištenja zabilježeno je smanjenje udjela polifenola u konzerviranim cvjetovima. Rezultati pokazuju da je konzerviranje cvjetova maslačka u sirupu s 30 °Bx i skladištenje tijekom 20 dana očuvalo njihov fenolni udjel i antioksidacijski kapacitet.
Novina i znanstveni doprinos. Brojna dosad objavljena istraživanja su usmjerena na produljenje vijeka trajanja voća i povrća metodom konzerviranja. Međutim, ovo istraživanje po prvi put izvješćuje o uspješnoj primjeni tehnike konzerviranja na jestive cvjetove. Nadalje, rezultati ovoga istraživanja pridonose budućim istraživanjima moguće komercijalizacije konzerviranih cvijetova maslačka kao prehrambenog proizvoda
Integration of GPS Data and Seismic Events using Lomb-Scargle Spectral Analysis: a Study of GPS Station SPLT
No full textThis study analyzes the long-term and seasonal variations in the GPS time series of the SPLT station, located in a seismically active region. By integrating data on seismic events with a time series of GPS coordinates, we identify coseismic displacements, especially emphasizing the variability of the vertical component. In the analysis, the Lomb-Scargle spectral method was used to estimate the spectral indices after the detection of seismic events, and to obtain detailed information about the changes in the spectral characteristics of the series. The results show significant changes in vertical motion, with the largest coseismic displacement recorded on January 13, 2005, during the seismic swarm. Seasonal oscillations significantly affect the vertical components, which suggests the need for precise modelling to reduce inaccuracies. We also find that seismic activity introduces higher frequency energy into GPS signals, changing the values of the spectral indices, especially in the vertical axis. These studies highlight the effectiveness of integrating geodetic and seismic data for monitoring crustal deformations and their contribution to a more detailed understanding of seismic dynamics in the Adriatic basin
Transmission Power System Planning Under New Generation Insecurity
No full textThe integration of renewable energy sources into the power grid presents significant challenges and opportunities for grid planners. Renewable energy sources such as wind and solar are variable and intermittent, leading to fluctuations in power output based on weather conditions and time of day. This variability necessitates the development of more flexible and responsive systems to balance supply and demand effectively. Traditional power plants, which provide consistent and controllable power, have long been the backbone of grid stability. However, the increasing penetration of renewables introduces complexities such as voltage instability and frequency fluctuations. To address these issues, grid planners must implement advanced technologies and strategies, including energy storage systems and smart grid technologies, to maintain stability and reliability. The transition to renewable energy also requires substantial upgrades to the existing grid infrastructure. This includes expanding transmission lines to connect remote renewable energy sites to the main grid and enhancing distribution networks to handle the increased load and variability. The shift towards a more decentralized energy system, where power generation occurs closer to consumption points, challenges traditional centralized grid models. Grid planners must now incorporate distributed energy resources (DERs) like rooftop solar panels and local wind turbines into their planning processes. By addressing these challenges, grid planners can create a more sustainable, reliable, and resilient energy system that effectively integrates renewable energy sources