Digital repository of Slovenian research organisations

Search the repository
A+ | A- | Help | SLO | ENG

Query: search in
search in
search in
search in

Options:
  Reset


Query: "author" (��erne Rok) .

51 - 60 / 142
First pagePrevious page234567891011Next pageLast page
51.
Extending BIM for air quality monitoring
Michael Nicolas Mrissa, Jan Vcelak, László Hajdu, Balázs Dávid, Miklós Ferenz Krész, Jakub Michal Sandak, Anna Malgorzata Sandak, Rok Kanduti, Monika Varkonji, Anja Jutraž, Katja Malovrh Rebec, 2020, published scientific conference contribution

Abstract: As we spend more than 90% of our time inside buildings, indoor environmental quality is a major concern for healthy living. Recent studies show that almost 80% of people in European countries and the United States suffer from SBS (Sick Building Syndrome), which affects physical health, productivity and psychological well-being. In this context, environmental quality monitoring provides stakeholders with crucial information about indoor living conditions, thus facilitating building management along its lifecycle, from design, construction and commissioning to usage, maintenance and end-of-life. However, currently available modelling tools for building management remain limited to static models and lack integration capacities to efficiently exploit environmental quality monitoring data. In order to overcome these limitations, we designed and implemented a generic software architecture that relies on accessible Building Information Model (BIM) attributes to add a dynamic layer that integrates environmental quality data coming from deployed sensors. Merging sensor data with BIM allows creation of a digital twin for the monitored building where live information about environmental quality enables evaluation through numerical simulation. Our solution allows accessing and displaying live sensor data, thus providing advanced functionality to the end-user and other systems in the building. In order to preserve genericity and separation of concerns, our solution stores sensor data in a separate database available through an application programming interface (API), which decouples BIM models from sensor data. Our proof-of-concept experiments were conducted with a cultural heritage building located in Bled, Slovenia. We demonstrated that it is possible to display live information regarding environmental quality (temperature, relative humidity, CO2, particle matter, light) using Revit as an example, thus enabling end-users to follow the conditions of their living environment and take appropriate measures to improve its quality
Keywords: Building Information Model, internet of things, environmental quality monitoring, healthy living
Published in DiRROS: 19.01.2024; Views: 539; Downloads: 233
.pdf Full text (18,89 MB)
This document has many files! More...

52.
53.
Hydrogeological characterization of karst springs of the white (Proteus anguinus anguinus) and black olm (Proteus anguinus parkelj) habitat in Bela krajina (SE Slovenia)
Katja Koren, Rok Brajkovič, 2023, original scientific article

Abstract: The springs west of Črnomelj, in SE Slovenia, are the habitat of the black (Proteus anguinus parkelj) and the white olm (Proteus anguinus anguinus). Some of these springs are also the only known habitat in the world of endemic species of black olm. A steady decline in olm populations has been observed in this area over the past decades. Owing to the rapid runoff and groundwater flow high-resolution monitoring is essential in providing better insight into the hydrogeological characterization of the catchment area of springs. Specific factors and critical parameters of water behind said olm degradation have not yet been defined. Because the olm’s environment is largely aquatic, one potential critical parameter could be the higher water temperatures (>12 °C) or higher nitrate concentration (>9.2mg/l). The six-month observation of the springs (July – December 2021) point to water temperature as a potential critical parameter since the water temperature of the springs exceeded 12 °C in months July and August. Nitrate concentrations could also be a second critical parameter in the degradation of the olm’s habitat. Maximum nitrate concentrations above 9.2mg/l throughout much of the observation period (except for Dobličica spring). Due to less agricultural activity in December in the spring catchment area and a higher dilution rate due to reduced evapotranspiration and increased effective precipitation during this time of the year, the nitrate concentrations are decreased. The results of the measured parameters of groundwater could show the hydrogeological connection between the Otovski and Pački breg springs and between Šotor, Jamnice and Dobličica. The Obršec spring has an independent catchment area. A detailed estimation of the springs catchment area is possible due to a detailed geologic map. It is necessary to determine the origin of the nitrate (nitrate isotope analysis), to quantify the threshold values of the critical parameters, to define precisely all the causes of the olm deterioration, and to make proposals for appropriate measures to limit or even stop the decline of the olm population.
Keywords: hydrogeology, olm, ecology, nitrate, monitoring
Published in DiRROS: 16.01.2024; Views: 432; Downloads: 133
.pdf Full text (13,65 MB)

54.
Geochemical and mineralogical approaches in unraveling paleoweathering, provenance, and tectonic setting of the clastic sedimentary succession (Western Central Paratethys)
Kristina Ivančič, Rok Brajkovič, Mirijam Vrabec, 2024, original scientific article

Abstract: Pronounced tectonic and paleogeographic changes were detected in the Alpine–Pannonian region during the Miocene at the interface between the Alps, the Dinarides, and the Pannonian Basin. To understand the major tectonic, paleogeographic, and paleoclimatic changes during this period, geochemical and mineralogical investigations were carried out on the fine-grained clastic sedimentary rocks in the Tunjice Hills. The paleoweathering indicates a cold and/or arid to a warm and humid period. The paleoclimate and the regional climatic conditions correspond well with the Middle Miocene Climatic Optimum. The mineral composition shows an abundance of quartz and calcite. Quartz is associated with detrital origin from volcanic and metamorphic rocks of the Eastern and Southern Alps and with authigenic processes in sediments. Calcite is related to authigenic origin formed in shallow marine environments and to detrital provenance from the Southern Alps. Not all discriminant functions based on major oxides provided adequate results in determining the tectonic setting. The source rocks were subjected to oceanic island arc and collision. Moreover, sedimentation was influenced by both active and passive margin settings. The former is related to the Alpine collision, which continued from the Cenozoic onward, and the latter is connected to the processes associated with the formation of the Pannonian Basin System, which began in the late Early Miocene.
Keywords: Central Paratethys, provenance, tectonic setting, paleoweathering, Miocene, Tunjice Hills
Published in DiRROS: 15.01.2024; Views: 391; Downloads: 139
.pdf Full text (13,59 MB)

55.
56.
O domorodnosti alpskega kozoroga v Sloveniji
Andreja Nève Repe, Elena Bužan, Borut Toškan, Jernej Javornik, Boštjan Pokorny, Andrej Arih, Lars Zver, Maruša Prostor, Miha Krofel, Matija Stergar, Klemen Jerina, Hubert Potočnik, Rok Černe, Aleš Poljanec, 2023, professional article

Abstract: Alpski kozorog (Capra ibex) je alpski endemit. Na območju Slovenije naj bi bila vrsta iztrebljena v drugi polovici 17. stoletja, globalno pa je bila zaradi prelova na robu izumrtja konec 19. stoletja. Preživela je le populacija na širšem območju parka Gran Paradiso na skrajnem zahodu Alp v Italiji. Zaradi naselitev in drugih varstvenih programov sedaj alpski kozorog živi v celotnih Alpah, vključno s Slovenijo. Vendar pri nas njegove populacije nazadujejo in so v zelo slabem stanju, kar je lahko rezultat več dejavnikov. Malo izvornih osebkov ob naselitvah, zgodovinska ozka grla in ločenost kolonij so povzročili parjenje v sorodstvu, kar je slabšalo genetsko stanje populacij in lahko negativno vpliva tudi na demografijo. K številčnemu zmanjševanju vrste so lahko prispevale tudi bolezni. Za dolgoročno ohranitev alpskega kozoroga v Sloveniji so nujni takojšnji aktivni ohranitveni ukrepi, pogoj pa je ustrezna opredelitev izvornosti vrste, saj je (bila) zaradi prejšnjih pomanjkljivih podatkov umeščena med tujerodne. V prispevku na podlagi arheo-zooloških, genetskih in preliminarnih habitatnih analiz utemeljujemo, da je v Sloveniji kozorog domorodna vrsta. V raziskavah smo pokazali, da je vrsta živela na ozemlju zdajšnje Slovenije v poznoantičnem in zgodnje srednjeveškem obdobju. Preliminarno smo določili tudi primernost in povezanost habitata kozoroga v slovenskem alpskem svetu ter nakazali verjetne potrebne ukrepe za ohranitev vrste v Sloveniji.
Keywords: Capra ibex, izvornost vrste, programi varstva, Alpe, habitat, genetika
Published in DiRROS: 09.01.2024; Views: 703; Downloads: 162
.pdf Full text (475,48 KB)

57.
Low but significant evolutionary potential for growth, phenology and reproduction traits in European beech
Marjana Westergren, Juliette Archambeau, Marko Bajc, Rok Damjanić, Adélaïde Theraroz, Hojka Kraigher, Sylvie Oddou-Muratorio, Santiago C. González-Martínez, 2023, original scientific article

Abstract: Local survival of forest tree populations under climate change depends on existing genetic variation and their adaptability to changing environments. Responses to selection were studied in European beech (Fagus sylvatica) under field conditions. A total of 1087 adult trees, seeds, 1-year-old seedlings and established multiyear saplings were genotyped with 16 nuSSRs. Adult trees were assessed for phenotypic traits related to growth, phenology and reproduction. Parentage and paternity analyses were used to estimate effective female and male fecundity as a proxy of fitness and showed that few parents contributed to successful regeneration. Selection gradients were estimated from the relationship between traits and fecundity, while heritability and evolvability were estimated using mixed models and the breeder's equation. Larger trees bearing more fruit and early male flowering had higher total fecundity, while trees with longer growth season had lower total fecundity (directional selection). Stabilizing selection on spring phenology was found for female fecundity, highlighting the role of late frosts as a selection driver. Selection gradients for other traits varied between measurement years and the offspring cohort used to estimate parental fecundity. Compared to other studies in natural populations, we found low to moderate heritability and evolvability for most traits. Response to selection was higher for growth than for budburst, leaf senescence or reproduction traits, reflecting more consistent selection gradients across years and sex functions, and higher phenotypic variability in the population. Our study provides empirical evidence suggesting that populations of long-lived organisms such as forest trees can adapt locally, even at short-time scales.
Keywords: climate change, Fagus sylvatica, heritability, in situ adaptation, response to selection, selection gradients
Published in DiRROS: 12.12.2023; Views: 546; Downloads: 242
.pdf Full text (6,82 MB)
This document has many files! More...

58.
Evolution of surface functional groups and aromatic ring degradation upon treatment of polystyrene with hydroxyl radicals
Alenka Vesel, Rok Zaplotnik, Gregor Primc, Miran Mozetič, 2023, original scientific article

Abstract: The surface properties of hydrocarbon polymers are inadequate for numerous applications. Hence, they require alteration via functionalisation with desired functional groups. Hydroxyl groups are often preferred, since they enable appropriate polarity for the irreversible grafting of desired molecules. In this study, the surface kinetics resulting from the treatment of polystyrene with hydroxyl (OH) radicals from the gas phase was fundamentally investigated through a precisely-designed experiment. Polystyrene samples were exposed to various known fluences of OH radicals, and the evolution of surface functional groups versus the OH fluence was monitored using high-resolution X-ray photoelectron spectroscopy (XPS). The fluences of OH radicals varied between 1 × 1018 and 4 × 1023 m−2 in the process of finding a threshold fluence for the formation of specific groups. The surface concentration of carbonyl (C=O) groups could be measured using XPS at a fluence of approximately 5 × 1020 m−2. The C=O groups became measurable at a fluence of approximately 1.5 × 1021 m−2, and carboxyl (COOH)/ester groups at approximately 4 × 1021 m−2. As deduced from the XPS, a concentration of C=O groups at approximately 5 % occurred before the degradation of the aromatic ring. The formation of other oxygen-functional groups required opening of the aromatic ring. The results have been explained using a two-step process, considering available theories vis-a-vis initial stages in the functionalisation of PS with polar functional groups.
Keywords: polistiren, kinetika površinske funkcionalizacije, OH radikali, vpliv doze radikalov, časovni razvoj, polystyrene, surface functionalisation kinetics, OH radicals
Published in DiRROS: 09.11.2023; Views: 543; Downloads: 220
URL Link to file

59.
Models for forecasting the traffic flow within the city of Ljubljana
Gašper Petelin, Rok Hribar, Gregor Papa, 2023, original scientific article

Abstract: Efficient traffic management is essential in modern urban areas. The development of intelligent traffic flow prediction systems can help to reduce travel times and maximize road capacity utilization. However, accurately modeling complex spatiotemporal dependencies can be a difficult task, especially when real-time data collection is not possible. This study aims to tackle this challenge by proposing a solution that incorporates extensive feature engineering to combine historical traffic patterns with covariates such as weather data and public holidays. The proposed approach is assessed using a new real-world data set of traffic patterns collected in Ljubljana, Slovenia. The constructed models are evaluated for their accuracy and hyperparameter sensitivity, providing insights into their performance. By providing practical solutions for real-world scenarios, the proposed approach offers an effective means to improve traffic flow prediction without relying on real-time data.
Keywords: traffic modeling, time-series forecasting, traffic-count data set, machine learning, model comparison
Published in DiRROS: 28.09.2023; Views: 647; Downloads: 276
.pdf Full text (5,05 MB)
This document has many files! More...

60.
Search done in 0.33 sec.
Back to top