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1.
Detoxified spent pot lining from aluminum production as (alumino-)silicate source for composite cement and autoclaved aerated concrete
Arne Peys, Mateja Košir, Ruben Snellings, Ana Mladenovič, Liesbeth Horckmans, 2021, original scientific article

Abstract: New sources of supplementary cementitious materials (SCMs) are needed to meet the future demand. A potential new source of SCM is spent pot lining, a residue from aluminum production. The present work showed that the refined aluminosilicate part of spent pot lining (SPL) has a moderate chemical reactivity in a cementitious system measured in the R3 calorimetry test, comparable to commercially used coal fly ash. The reaction of SPL led to the consumption of Ca(OH)2 in a cement paste beyond 7 days after mixing. At 28 and 90 days a significant contribution to strength development was therefore observed, reaching a relative strength, which is similar to composite cements with coal fly ash. At early age a retardation of the cement hydration is caused by the SPL, which should most likely be associated with the presence of trace amounts of NH3. The spent pot lining is also investigated as silica source for autoclaved aerated concrete blocks. The replacement of quartz by spent pot lining did not show an adverse effect on the strength-density relation of the lightweight blocks up to 50 wt% quartz substitution. Overall, spent pot lining can be used in small replacement volumes (30 wt%) as SCM or as replacement of quartz (50 wt%) in autoclaved aerated concrete blocks.
Keywords: spent pot lining, construction materials, recycling, autoclaved aerated conctrte, supplementary cementitious material
Published in DiRROS: 04.12.2023; Views: 161; Downloads: 68
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2.
Cost-benefit analysis of fire protection in buildings : application of a present net value approach
Thomas Gernay, Shuna Ni, David Unobe, Andrea Lucherini, Ranjit Kumar Chaudhary, Ruben Van Coile, 2023, original scientific article

Abstract: In fire safety engineering, cost–benefit analysis provides a systematic method to assess whether the projected benefits from a fire safety measure outweigh its costs. However, there remains a wide discrepancy between methods used in the field for cost–benefit analysis, as well as a lack of quantitative data on the costs and economic impact of fire protection in buildings. In a recent research project, a reference methodology was proposed based on Present Net Value evaluation and on a combination of specialized construction database, fire statistics, and numerical modeling for estimation of the cost components. This paper presents the application of the methodology to four case studies. The case studies allow describing the methodology, the collection of data, fire statistics, and loss estimation, as well as illustrating how the methodology can support decision-making when multiple alternatives are compared. Under the assumptions adopted for the single-family house and the residential timber building case studies, it is found that for every 1\$, invested in sprinklers, \$1.06 is saved. This benefit–cost ratio increases with increasing valuation of indirect losses and statistical value of life. Sensitivity analyses are provided to explore the robustness of the investment recommendations. The results of evaluations, adapted from the presented case studies with project-specific inputs, can support decision making for policy makers, insurance companies, and individual building owners.
Keywords: fire safety, cost-benefit analysis, fire protection, fire statistics, sprinklers, compartmentation
Published in DiRROS: 29.11.2023; Views: 223; Downloads: 30
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3.
Cost-benefit analysis in fire safety engineering : state-of-the-art and reference methodology
Ruben Van Coile, Andrea Lucherini, Ranjit Kumar Chaudhary, Shuna Ni, David Unobe, Thomas Gernay, 2023, original scientific article

Abstract: Cost-effectiveness is a key consideration within fire safety engineering. Currently, different approaches are being applied in literature. These approaches differ in how cost-effectiveness is evaluated, which costs are considered, and how the preferred design solution is defined. Recognizing this issue, the Fire Protection Research Foundation enrolled an international team of researchers, supported by a broad stakeholder panel, to develop a reference methodology. In this paper, this reference methodology for cost-benefit analysis in fire safety engineering is presented following an extensive literature review. The methodology clarifies the minimum requirements for assessing cost-effectiveness, and highlights that only a present net value evaluation can be used to compare design alternatives. Commonly used cost-benefit ratios should only be used when deciding on the effectiveness of a single package of fire safety measures. An illustrative case study demonstrates the application of the meth- odology and shows how designs based on cost-benefit ratios can be sub-optimal when evaluating multiple possible fire safety measures.
Keywords: cost-benefit analysis, fire safety, investment, maintenance, loss, statistics, reliability
Published in DiRROS: 23.10.2023; Views: 274; Downloads: 62
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4.
Private forest owner willingness to mobilise wood from dense, small-diameter tree stands
Matevž Triplat, Satu Helenius, Ruben Laina, Nike Krajnc, Thomas Kronholm, Zdenka Ženko, Teppo Hujala, 2023, original scientific article

Abstract: Forests are a source of renewable biomass, and their utilisation will play a vital role in the transition towards a climate-neutral economy. Small-diameter tree management could contribute to this transition via providing renewable biomass for sustainable uses and fostering tree growth towards long-lifecycle bioproducts. The utilisation of small-diameter trees in the EU is still low since new technologies and work models are required to make the operations economically profitable, environmentally sound, and socially attractive. The supply of biomass from small-diameter tree stands is dependent on forest owners with diverse perceptions on their forests and diverse ownership objectives. However, there is scarce research on forest owner perceptions on small-diameter tree management, which encompasses home consumption, self-active work, and commercial forestry services. A survey in four EU countries was designed to identify the main factors affecting the motivation of forest owners to mobilise biomass from small-diameter stands. Factor and clustering analyses were used to identify four forest owner segments: weakly-engaged traders, well-being seekers, self-active profit-seekers, and well-informed service users. The willingness to utilise biomass from small-diameter tree stands and participate in the market was shaped by forest owner knowledge of forestry, economic and socio-cultural motivations, and sensitivity to service offerings. Forest owner preferences for market participation are heterogenous, and thus different policy implementation approaches are needed and proposed.
Keywords: customer profiles, factor analysis, forestry services, management objectives, biomass, communication strategies
Published in DiRROS: 05.01.2023; Views: 605; Downloads: 236
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5.
6.
Environmental impacts of boom-corridor and selectively thinned small-diameter-tree forests
Teresa de la Fuente, Dan Bergström, Raul Fernandez-Lacruz, Teppo Hujala, Nike Krajnc, Ruben Laina, Tomas Nordfjell, Matevž Triplat, Eduardo Tolosana, 2022, original scientific article

Abstract: European forest stands of small-diameter trees can provide industries with biomass as an alternative to fossil use. Small-tree harvesting is costly using conventional methods but using accumulating felling heads (AFH) in combination with a novel boom-corridor thinning (BCT) technique can increase harvester productivity and supply cost efficiency. This method has great potential to reduce costs, but its environmental impact compared with selective thinning (ST) needs to be determined. The objectives of this study were therefore to quantify and compare tree and soil damage as well as air, water and soil emissions for both BCT and ST in various European small-diameter-tree forests. Trials were performed in 84 study units (42 replications per thinning technique) across four countries. Damaged trees (with a diameter at breast height ≥ 7 cm) were measured after thinning and after forwarding. Harvesting emissions were calculated from a life cycle assessment. The percentage of remaining trees that had been damaged by the harvesting processes was 13% and 19% for BCT and ST, respectively, and the difference was significant. BCT exhibited the lowest emissions in all environmental impact categories considered, in all countries. Greenhouse gas emissions were on average 17% lower for BCT. BCT in small-diameter-tree stands therefore reduces the environmental impact of thinning operations compared with conventional methods, and results in less damage to the remaining trees.
Keywords: first thinning, harvesting damages, GHG emissions, forest biomass, forest operations
Published in DiRROS: 17.05.2022; Views: 633; Downloads: 356
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7.
A meta-analysis of global fungal distribution reveals climate-driven patterns
Tomáš Větrovský, Petr Kohout, Martin Kopecky, Antonin Machac, Matěj Man, Barbara Doreen Bahnmann, Vendula Brabcová, Jinlyung Choi, Lenka Mészárosová, Zander Rainier Human, Clémentine Lepinay, Rubén López-Mondéjar, Tijana Martinović, 2019, original scientific article

Abstract: The evolutionary and environmental factors that shape fungal biogeography are incompletely understood. Here, we assemble a large dataset consisting of previously generated mycobiome data linked to specific geographical locations across the world. We use this dataset to describe the distribution of fungal taxa and to look for correlations with different environmental factors such as climate, soil and vegetation variables. Our meta-study identifies climate as an important driver of different aspects of fungal biogeography, including the global distribution of common fungi as well as the composition and diversity of fungal communities. In our analysis, fungal diversity is concentrated at high latitudes, in contrast with the opposite pattern previously shown for plants and other organisms. Mycorrhizal fungi appear to have narrower climatic tolerances than pathogenic fungi. We speculate that climate change could affect ecosystem functioning because of the narrow climatic tolerances of key fungal taxa.
Keywords: fungi, global distribution, climate
Published in DiRROS: 03.01.2022; Views: 753; Downloads: 551
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8.
Ocena stanja ohranjenosti habitatnega tipa 91E0* Obrečna vrbovja, jelševja in jesenovja v območju Natura 2000 Ličenca pri Poljčanah
Ajša Alagić, Lado Kutnar, Erika Kozamernik, Valerija Babij, Aleksander Marinšek, Janez Kermavnar, Anica Simčič, Ruben Šprah, 2021, original scientific article

Abstract: Stanje ohranjenosti sestojev habitatnega tipa 91E0* Obrečna vrbovja, jelševja in jesenovja (Alno-Padion, Alnion incanae, Salicion albae) je v Sloveniji precej zaskrbljujoče. V Sloveniji je bilo njegovo stanje ocenjeno kot slabo, trend pa negativen, kar pomeni dodatno možnost poslabšanja. Omenjeni gozdni habitatni tip sodi med prioritetne ali prednostne habitatne tipe, za katere je predvidena posebna skrb Evropske skupnosti. Zaradi njegove majhnosti in fragmentiranosti je pogosto spregledan in tudi neustrezno obravnavan. Z namenom, da bi izboljšali njegovo prepoznavnost in spoznali njegove značilnosti na terenu, smo mu v okviru LIFE integriranega projekta za okrepljeno upravljanje Nature 2000 v Sloveniji namenili posebno pozornost. V raziskavi smo z uporabo metode terenskega kartiranja podrobneje proučili stanje sestojev habitatnega tipa 91E0* v območju Natura 2000 Ličenca pri Poljčanah. Na tak način smo ugotovili, kakšna je površina sestojev tega habitatnega tipa in jo primerjali z obstoječimi conami habitatnega tipa 91E0*. Ugotavljali smo pojavljanje ključnih drevesnih vrst oz. drevesno sestavo sestojev, njihovo pomlajevanje ter vrste pritiskov in groženj za habitatni tip 91E0* na tem območju. Izmed različnih znanih podtipov habitatnega tipa 91E0* smo na tem območju našli predvsem podtip nižinsko črnojelševje, pa tudi fragmente podtipa vrbovja s topolom. Ponekod so se tudi v gozdu pojavljali manjši sestoji vrb in ozkolistnega jesena. Ugotovili smo, da površine sestojev habitatnega tipa 91E0* na območju Natura 2000 Ličenca pri Poljčanah dejansko zavzemajo le približno četrtino površine obstoječih con habitatnega tipa. Analiza drevesne sestave sestojev je pokazala predvsem vraščanje smreke v sestojih črnojelševja, le-ta naravno ni prisotna v tem habitatnem tipu. Ugotovili smo, da je na proučevanem območju pomlajevanje črne jelše zelo okrnjeno. Na slabšanje stanja sestojev črnojelševja še dodatno vplivajo različni pritiski in grožnje, kot so bližina kmetijskih površin, odpadki, fragmentacija sestojev črnojelševja, širjenje invazivnih tujerodnih rastlin, vodne regulacije, bližina prometnic, izsuševanje rastišč idr. Stanje ohranjenosti sestojev tega habitatnega tipa je bilo posledično v večini primerov ocenjeno kot neugodno do slabo. Z namenom, da bi se stanje obrečnih gozdov na območju Ličence pri Poljčanah izboljšalo, smo v prispevku predlagali nekaj konkretnih ohranitvenih ukrepov
Keywords: habitatni tip, črnojelševje, obrečni gozdovi, terensko kartiranje, stanje ohranjenosti, Alnus glutinosa, Natura 2000
Published in DiRROS: 14.04.2021; Views: 1546; Downloads: 537
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