15 research outputs found
Calculating concentration of explosive fumes in the Stupe sewerage tunnel
Prikazani su rezultati matematiÄkog modeliranja strujanja zraka i sadržaja eksplozivnih plinova u hidrotehniÄkom kanalizacijskom tunelu Stupe u Splitu. Modeliranje je provedeno radi procjene ugroženosti tunela od eksplozivnih i zapaljivih plinova. Prikazani su rezultati proraÄuna stacionarnog strujanja pri radu ventilatora te prirodnoj ventilaciji. Istaknuto je da se na temelju provedenih istraživanja i analiza može zakljuÄiti da nema opasnosti od pojave plinova u tunelu.Results obtained by mathematical modeling of the air flow and content of explosive fumes in the Stupe sewerage tunnel in Split, are presented. The modeling was performed in order to estimate exposure of this tunnel to the action of explosive and inflammable gases. Stationary flow calculation results, obtained during fan-assisted ventilation and during natural ventilation, are presented. It is emphasized that the modeling and analyses conducted in this research show that there is no gas hazard in this sewerage tunnel
Calculating concentration of explosive fumes in the Stupe sewerage tunnel
Prikazani su rezultati matematiÄkog modeliranja strujanja zraka i sadržaja eksplozivnih plinova u hidrotehniÄkom kanalizacijskom tunelu Stupe u Splitu. Modeliranje je provedeno radi procjene ugroženosti tunela od eksplozivnih i zapaljivih plinova. Prikazani su rezultati proraÄuna stacionarnog strujanja pri radu ventilatora te prirodnoj ventilaciji. Istaknuto je da se na temelju provedenih istraživanja i analiza može zakljuÄiti da nema opasnosti od pojave plinova u tunelu.Results obtained by mathematical modeling of the air flow and content of explosive fumes in the Stupe sewerage tunnel in Split, are presented. The modeling was performed in order to estimate exposure of this tunnel to the action of explosive and inflammable gases. Stationary flow calculation results, obtained during fan-assisted ventilation and during natural ventilation, are presented. It is emphasized that the modeling and analyses conducted in this research show that there is no gas hazard in this sewerage tunnel
Design solution for the Jurin kuk tunnel
U Älanku je prikazan i obrazložen glavni projekt tunela āJurin kukā koji se nalazi u sklopu županijske ceste, na dionici Gata ā ZveÄanje u zaleÄu OmiÅ”a. Opisane su osnovne prometne i geometrijske karakteristike tunela. Prikazano je projektno rjeÅ”enje i komentirana Å”ira problematika izgradnje tunela. GeoloÅ”ke i geotehniÄke karakteristike terena takoÄer su prikazane, a posebno karakteristike stjenske mase i naÄin iskopa i podgrade te usvojena geotehniÄka i graÄevinska rjeÅ”enja.The detailed design for the Jurin kuk tunnel, situated on the county road between Gata and ZveÄanje, in the OmiÅ” hinterland area, is presented. Basic geometrical and transport-related properties of the tunnel are described. The design solution is presented, and problems generally encountered during tunnel construction are commented on. Geological and geotechnical properties of the terrain are also presented, with a special emphasis on the rock mass, excavation method and support work, and on geotechnical and structural solutions adopted on this project
Investigations and design solution for the Stupe hydropower tunnel
Opisani su opsežni istražni radovi na lokaciji hidrotehniÄkog tunela Stupe u Splitu koji su poslužili za izradu projektne dokumentacije. Rezultati istraživanja bili su osnova za klasifikaciju i kategorizaciju stijenske mase. Tako odreÄene geotehniÄke karakteristike bili su odluÄujuÄe pri odabiru trase tunela i za projektiranje podgradnog sustava koji je predviÄen kao tunelska obloga. Na kraju su navedeni podaci o tijeku iskopa tunela pri Äemu su opisane i karakteristike tla.Authors describe extensive investigations on the site of the Stupe hydropower tunnel in Split which were underaken in order to enable preparation of design documents. The investigation results were the basis for the rock mass classification and categorization, which is also presented in the paper. Geotechnical properties defined in this way were of crucial significance for the selection of the tunnel route and for designing the support system for which tunnel lining has been adopted. Finally, a brief account is given of the construction process, including data on soil properties
Study of the Aqueduct of Salona 2014-2015
U ovom radu bit Äe prezentirani rezultati istraživanja
trase i znaÄajki Salonitanskog akvedukta koji su
provedeni tijekom prve godine znanstvenog projekta
āAntiÄki vodni sustavi grada Salone i Dioklecijanove palaÄe i njihov utjecaj na održivost urbane sredineā
koji financira Hrvatska zaklada za znanost. Prvi put je
u cijelosti utvrÄena trasa akvedukta, njegov uzdužni
profil, kapacitet i karakteristiÄni presjeci u razliÄitim
terenskim uvjetima, kao i naÄin gradnje.This paper will present the results obtained by the
study of the route and the physical characteristics of
the Aqueduct of Salona. The study was conducted during
the first year of the research project entitled āAncient
Water Systems of Salona and the Diocletianās
Palace and Their Impact on the Sustainability of the
Urban Environmentā, which has been financed by the
Croatian Science Foundation. The significance of the study lies in the fact that, the overall route of the Aqueduct,
its longitudinal profile, capacity, typical sections
in various field conditions, as well as the method of
construction have been determined for the first time
Nalazi meduze Aequorea cf. forskalea u Jadranskom moru: usporedba povijesnih i recentnih podataka
Jellyfish are becoming an increasingly important component of studies of the global marine environment, as their frequent mass phenomena affect ecosystem performance and have economic and health consequences. Recent research has focused primarily on mass occurrences of scyphozoans
and ctenophores, while less attention has been paid to hydromedusae blooms, which can also have
significant impacts on the marine ecosystem with economic consequences. Like many members of
the Scyphozoa and Ctenophora, Aequorea species can be numerous and form blooms. Based on surveys from 2000 to 2020 and information provided by marine professionals, we examine the (multiannual) variability, seasonality, and spatial distribution patterns of the poorly studied temperate species Aequorea cf. forskalea (Hydrozoa: Leptothecata). We hypothesized that this macrogelatinous jellyfish with a bipartite life cycle (benthic polyps and planktonic medusae) is sensitive to seasonal
and long-term temperature fluctuations, particularly because temperature has been shown to play
a critical role in mediating transitions in the life cycle of cnidarians. The cold-water affinity of A.
cf. forskalea was confirmed by a significant negative correlation with temperature and the most frequent occurrence during the winter-spring period. For the northern Adriatic (Gulf of Trieste), sea temperature data and semi-quantitative plankton data are available for the first decade of the 20th
century, allowing comparison of the historical data (1900-1911) with our current data set. Compared to historical records, the current occurrence of A. cf. forskalea differs significantly. With the warming of the northern Adriatic Sea since the beginning of the 20th century, the current phenology
of A. cf. forskalea has changed, probably related to the delayed production of medusae by hydroids
in autumn, the absence of medusae in this season and their less frequent occurrence in winter.Meduze postaju sve važnija komponenta globalnog prouÄavanja morskog okoliÅ”a, buduÄi da
njihove Äeste masovne pojave utjeÄu na održanje ekosustava, a imaju ekonomske i zdravstvene
posljedice. Najnovija su istraživanja usmjerena prvenstveno na masovnu pojavu režnjaka (Scyphozoa) i rebraÅ”a (Ctenophora), dok se manje pažnje posveÄuje masovnim pojavama hidromeduza, koje takoÄer mogu imati veliki utjecaj na morski ekosustav sa znaÄajnim ekonomskim posljedicama.
Poput mnogih pripadnika Scyphozoa i Ctenophora, vrste roda Aequorea se mogu javljati u visokim
brojnostima te njihovu pojavu možemo opisati kao masovnu (ābloomā). Na temelju podataka prikupljenih tijekom istraživanja Jadrana u razdoblju od 2000. do 2020. godine te informacija dobivenih od struÄnjaka koji se bave istraživanjem mora, razmatrali smo viÅ”egodiÅ”nju i sezonsku varijabilnost
kao i obrasce prostorne raspodjele slabo prouÄavane vrste Aequorea cf. forskalea (Hydrozoa: Leptothecata) koja nastanjuje umjerena klimatska podruÄja. Pretpostavili smo da je ova makro-želatinozna meduza, s bipartitnim životnim ciklusom (bentoski polipi i planktonske meduze), osjetljiva na sezonske i dugoroÄne promjene temperaturne, buduÄi da temperatura igra kljuÄnu ulogu za izmjenu
generacija u životnom ciklusu žarnjaka (Cnidaria). Afinitet A. cf. forskalea prema hladnoj morskoj
vodi potvrÄuje znaÄajna negativna korelacija s temperaturom te uÄestalo pojavljivanje tijekom zimsko-proljetnog razdoblja. Podaci o temperaturi mora i abundancijama vrste su dostupni za sjeverni Jadran (TrÅ”Äanski zaljev) za prvo desetljeÄe 20. stoljeÄa, Å”to je omoguÄilo usporedbu povijesnih
podataka (1900.-1911.) s novim setom podataka. U usporedbi s povijesnim zapisima, recentna se
pojava A. cf. forskalea znaÄajno razlikuje. Sa zatopljenjem sjevernog dijela Jadranskog mora od
poÄetka 20. stoljeÄa se mijenja sadaÅ”nja fenologija vrste A. cf. forskalea, Å”to je vjerojatno povezano
sa zakaÅ”njelom proizvodnjom meduza u jesen, izostankom tijekom jeseni i njihovom rjeÄom pojavom tijekom zime