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1.
Spatially explicit individual-based model reveals the mauve stinger jellyfish distribution in the Mediterranean Sea
Martin Vodopivec, Alenka Malej, 2025, izvirni znanstveni članek

Povzetek: The mauve stinger Pelagia noctiluca is a holoplanktonic oceanic jellyfish known for its painful sting and large outbreaks at irregular intervals. As jellyfish field observations are almost exclusively limited to coastal regions, there are many unknowns about the spatial and temporal dynamics of most species. We approach the problem using a spatially explicit individual-based model for the mauve stinger in the Mediterranean Sea. The newly developed module for the OpenDrift Lagrangian particle tracking tool includes diel vertical migrations, fooddependent growth modeled on Michaelis–Menten kinetics, and custom mortality related to shallow waters and stranding. In the first part of the study, we analyze the resulting parameter space searching for solutions that ensure a stable Pelagia noctilucapopulation in the western Mediterranean Sea. In the second part, we conducted several 21-year simulations. Despite its relative simplicity, the model reveals for the first time the dynamic spatio-temporal distribution of Pelagia noctiluca. We demonstrate how spatially explicit individual-based model can be used to generate a realistic spatio-temporal distribution of marine zooplankton, even with a limited set of observations and loosely constrained parameters. The model code is easy to modify and freely available.
Ključne besede: individual-based model, agent-based model, zooplankton, Lagrangian particle tracking, ocean circulation, jellyfish
Objavljeno v DiRROS: 05.06.2025; Ogledov: 142; Prenosov: 81
.pdf Celotno besedilo (5,98 MB)
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2.
Age-dependent moisture response of conifers near their cold range limit
Jan Tumajer, Grudd Håkan, Jernej Jevšenak, Andreas J. Kirchhefer, Francesco Marotta, Jiří Mašek, Kiara Maria Nowatzki, Nikolaus Obojes, Markus Stoffel, V. Treml, Jelena Lange, 2025, izvirni znanstveni članek

Povzetek: Growth dynamics of cold subarctic and subalpine forests are primarily sensitive to temperature, but growth responses may vary across regions or shift over tree ontogeny. Systematic assessments of spatial, interspecific, and demographic variation in temperature and moisture limitation of tree growth at cold distribution margins are essential for enhancing our understanding of how these ecosystems will evolve under climate regimes. To address this gap, we built a network of 22 tree-ring width chronologies from cold forests covering two regions (Fennoscandia, European Alps), three species (Pinus sylvestris, Pinus cembra, Larix decidua), and two age cohorts (45–100 and >150 years). We combined daily climate-growth correlations with the process-based Vaganov-Shashkin growth model to identify differences in critical growth factors between species and age cohorts. In addition, we assessed the coincidence of unusually wide and narrow tree rings with years of specific climatic anomalies. Although growing season temperature was the dominant growth-limiting factor, seasonal effects of water balance on tree growth were considerably large and varied systematically between regions, species, and particularly age cohorts. The growth of young P. sylvestris in Fennoscandia responded negatively to water balance and narrow rings coincided with wet years. In contrast, the growth of young P. cembra in the Alps was drought-limited. Old trees of all species and both age cohorts of L. decidua in the Alps showed limited sensitivity to water balance. The patterns of climate-growth responses in cohort chronologies based on tree age at the year of coring were similar to ontogenetic shifts of climate-growth responses if chronologies were based on the cambial age of individual rings. Our results stress the need to account for interspecific and demographic differences in sensitivity to climate in large-scale studies of cold forest ecosystems.
Ključne besede: boreal forest, Larix, subalpine forest, pinus, tree ring, Vaganov-Shashkin model
Objavljeno v DiRROS: 04.06.2025; Ogledov: 129; Prenosov: 58
.pdf Celotno besedilo (10,22 MB)
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3.
A simple multiple flow regime modeling approach of induced flow in external loop airlift reactors
Bor Zupan, Matjaž Perpar, Jurij Gregorc, Božidar Šarler, 2025, izvirni znanstveni članek

Povzetek: Accurate treatment of heat and mass transfer processes inside airlift reactors requires accurate velocity field information. This study presents a novel one-dimensional model forecasting induced liquid flow within an external loop airlift reactor across diverse flow regimes. The approach is grounded on homogeneous flow assumption, augmented by a novel correction term derived through modeling of turbulence-induced pressure losses behind gas structures, employing the separated flow model (Lockhart-Martinelli). The model was assessed by comparing the results with purpose-provided experimental data utilizing air and demineralized water. The gas and liquid superficial velocities ranged from 0.001-0.6 m/s and 0.2–1.1 m/s, respectively. Within ± 10 %, an agreement between the novel model and experimental data was observed for both bubbly, separated, and in- termediate flow regimes. A similarly robust agreement was confirmed through comparisons with five published experimental datasets. The distinctive feature of this model is its ability to accommodate multiple flow regimes in a unified manner. It circumvents the necessity for specific regime modeling by introducing a correction term with a complexity marginally surpassing that of the conventional homogeneous flow approach. Beyond its primary application in airlift reactors, the model provides a unified framework for modeling two-phase flow hydrody- namics in thermal applications, particularly in flow boiling and bubble-induced convective heat transfer systems. The model’s simple yet effective structure also allows for integration into higher-fidelity heat transfer simula- tions, making it valuable for boiling heat transfer studies, enhanced cooling strategies, and industrial multiphase flow applications.
Ključne besede: airlift reactor, homogeneous flow, separated flow, theoretical model, induced flow
Objavljeno v DiRROS: 13.05.2025; Ogledov: 169; Prenosov: 71
.pdf Celotno besedilo (4,69 MB)
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Considering the concept of synergism in corrosion inhibition
Anton Kokalj, 2023, izvirni znanstveni članek

Povzetek: Synergism in corrosion inhibition and how to best quantify it is explored conceptually. In the equation for the synergistic parameter, the mixture’s inhibition efficiency is evaluated against a threshold inhibition efficiency based on the performance of pure compounds. However, the choice for the threshold value is not unique. In the literature, the threshold of Aramaki–Hackerman is usually used. Herein, several other reasonable choices are developed, which are based on (i) the Langmuir adsorption model, (ii) the requirement that a mixture’s inhibition efficiency is higher than the highest inhibition efficiency of pure compounds, or (iii) that corrosion resistance in a mixture is higher than the sum of resistances in pure compounds. The presented synergistic models are also extended to multi-component mixtures.
Ključne besede: corrosion inhibition, synergism, Langmuir adsorption model
Objavljeno v DiRROS: 23.04.2025; Ogledov: 198; Prenosov: 52
.pdf Celotno besedilo (1,65 MB)

7.
Runoff and evapotranspiration–precipitation ratios as indicators of water regulation ecosystem services in urban forests
Urša Vilhar, 2025, izvirni znanstveni članek

Povzetek: As a form of green infrastructure, urban forests play a key role in the provision of hydrological ecosystem services (ESs) in cities. Understanding how urban forest structure and soil properties influence water regulation ESs is crucial for managing and planning green infrastructure in cities. We analysed two indicators—the runoff to precipitation (Q/P) and the evapotranspiration to precipitation (ETP/P) ratios—for five different urban forests. We used the hydrological model Brook90 over 16 years to simulate runoff, evapotranspiration, canopy interception, transpiration and soil evaporation. The results showed that mixed forests have the highest water retention capacity, with the lowest Q/P (0.41) and the highest ETP/P (0.59). In contrast, riparian deciduous forests had the lowest water retention capacity, with the highest Q/P (0.75) and the lowest ETP/P (0.25). Both indicators showed similar annual and seasonal results. However, Q/P showed strong inter-annual variation and a strong correlation with precipitation, while ETP/P remained consistent despite precipitation fluctuations in the observed years. In conclusion, the ETP/P ratio is better suited to assess the water regulation ES of urban forests.
Ključne besede: stand structure, tree species composition, soil properties, hydrological model Brook90, urban ecosystems, precipitation, transpiration, urban green space, urban green infrastructure
Objavljeno v DiRROS: 14.04.2025; Ogledov: 284; Prenosov: 95
.pdf Celotno besedilo (2,38 MB)
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8.
Verjetnostna napoved sanitarnega poseka smreke zaradi podlubnikov v Sloveniji v 2025
Nikica Ogris, Maarten De Groot, 2025, drugi znanstveni članki

Povzetek: Naredili smo verjetnostno napoved sanitarnega poseka navadne smreke zaradi podlubnikov v 2025 v Sloveniji. Napoved smo naredili s pomočjo prostorskega modela, ki je bil razvit z logistično regresijo in ima ločljivost 1 km × 1 km. Napoved modela temelji na podatkih iz lanskega leta. Sanitarni posek smreke zaradi podlubnikov se bo v letu 2025 verjetno zgodil v 52,6 % modelskih celic s smreko. Med najbolj ogroženimi so naslednja gozdnogospodarska območja: Slovenj Gradec, Nazarje in Kranj.
Ključne besede: navadna smreka, Picea abies, sanitarni posek, napoved, prognoza, model, smrekovi podlubniki, ogroženost, Ips typographus, Slovenija
Objavljeno v DiRROS: 14.04.2025; Ogledov: 194; Prenosov: 171
.pdf Celotno besedilo (1011,52 KB)
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9.
The European Fault-Source Model 2020 (EFSM20) : geologic input data for the European Seismic Hazard Model 2020
Roberto Basili, Laurentiu Danciu, Céline Beauval, Karin Sesetyan, Susana Vilanova, Shota Adamia, Jure Atanackov, Petra Jamšek Rupnik, Barbara Šket Motnikar, Polona Zupančič, 2024, izvirni znanstveni članek

Povzetek: Earthquake hazard analyses rely on seismogenic source models. These are designed in various fashions, such as point sources or area sources, but the most effective is the three-dimensional representation of geological faults. We here refer to such models as fault sources. This study presents the European Fault-Source Model 2020 (EFSM20), which was one of the primary input datasets of the recently released European Seismic Hazard Model 2020. The EFSM20 compilation was entirely based on reusable data from existing active fault regional compilations that were first blended and harmonized and then augmented by a set of derived parameters. These additional parameters were devised to enable users to formulate earthquake rate forecasts based on a seismic-moment balancing approach. EFSM20 considers two main categories of seismogenic faults: crustal faults and subduction systems, which include the subduction interface and intraslab faults. The compiled dataset covers an area from the Mid-Atlantic Ridge to the Caucasus and from northern Africa to Iceland. It includes 1248 crustal faults spanning a total length of ∼95 100 km and four subduction systems, namely the Gibraltar, Calabrian, Hellenic, and Cyprus arcs, for a total length of ∼2120 km. The model focuses on an area encompassing a buffer of 300 km around all European countries (except for Overseas Countries and Territories) and a maximum of 300 km depth for the subducting slabs. All the parameters required to develop a seismic source model for earthquake hazard analysis were determined for crustal faults and subduction systems. A statistical distribution of relevant seismotectonic parameters, such as faulting mechanisms, slip rates, moment rates, and prospective maximum magnitudes, is presented and discussed to address unsettled points in view of future updates and improvements. The dataset, identified by the DOI https://doi.org/10.13127/efsm20 (Basili et al., 2022), is distributed as machine-readable files using open standards (Open Geospatial Consortium).
Ključne besede: earthquakes, hazard, European Fault-Source Model 2020 (EFSM20), Europe
Objavljeno v DiRROS: 08.04.2025; Ogledov: 214; Prenosov: 97
.pdf Celotno besedilo (5,40 MB)
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