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Biografi [swe]

Dr Ying Zhen Li is a senior research scientist at RISE and also an associate Professor (Docent) affiliated with Luleå University of Technology. He chairs the Scientific Committee of the International Symposium on Tunnel Safety and Security (ISTSS). He also serves as associate editor of Tunnelling and Underground Space Technology, guest editor of Fire Safety Journal, editorial board member of Underground Space, and editorial board member of Frontiers in Heat and Mass Transfer. He has published more than 100 scientific/technical publications concerning tunnel fire safety, co-authored the book “Tunnel Fire Dynamics”, and has been the winner of several prestigious awards such as the SFPE Jack Bono Award and the ITA COSUF Award.

His main research interests are in fire dynamics and fire suppression in tunnels, fire and explosion hazards of alternative fuel vehicles, scale modelling and CFD modelling of fire and explosion flows.

Publikasjoner (10 av 117) Visa alla publikasjoner
He, K., Li, Y. Z., Ingason, H., Shi, L. & Cheng, X. (2024). Experimental study on the maximum ceiling gas temperature driven by double fires in a tunnel with natural ventilation. Tunnelling and Underground Space Technology, 144, Article ID 105550.
Åpne denne publikasjonen i ny fane eller vindu >>Experimental study on the maximum ceiling gas temperature driven by double fires in a tunnel with natural ventilation
Vise andre…
2024 (engelsk)Inngår i: Tunnelling and Underground Space Technology, ISSN 0886-7798, E-ISSN 1878-4364, Vol. 144, artikkel-id 105550Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The maximum gas temperature below the ceiling is an important parameter for tunnel safety. The present study analyzed the characteristics of the maximum excess ceiling gas temperature driven by double fire sources in a naturally ventilated tunnel. A series of small-scale tunnel fire experiments were carried out with different fire separation distances and heat release rates. Theoretical analysis based on the equivalent virtual origin was also performed. The results showed that there exists only one peak gas temperature when the two fire plumes are merged before reaching the ceiling, while two peak gas temperatures can be observed when the two fire plumes are completely separated. The maximum excess gas temperature below the tunnel ceiling gradually decreases with an increasing fire separation distance in the plume merging region (S < Scp). When the fire separation distance increases further (S > Scp), the effect of the fire separation distance on the maximum gas temperature below the ceiling is very limited. Furthermore, a model using an equivalent fire source was proposed to predict the maximum excess gas temperature below the ceiling, considering different plume merging states. The present study contributes to the understanding of the maximum excess gas temperature characteristics of the smoke flow driven by double fires with an equal heat release rate in naturally ventilated tunnels. 

sted, utgiver, år, opplag, sider
Elsevier Ltd, 2024
Emneord
Ceilings; Fires; Gases; Merging; Smoke; Thermal plumes; Ventilation; Double fire source; Fire separation; Gas temperature; Heat release; Maximum excess gas temperature; Natural ventilation; Separation distances; Temperature profiles; Tunnel fires; Ventilated tunnels; Gas temperature
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-68815 (URN)10.1016/j.tust.2023.105550 (DOI)2-s2.0-85180417123 (Scopus ID)
Forskningsfinansiär
Brandforsk
Merknad

This work was financially supported by National Key Research and Development Program of China (No. 2022YFC3005201 ), the Tunnel and Underground Safety Center (TUSC), the Swedish Fire Research Board (BRANDFORSK), Youth Innovation Promotion Association CAS (No. CX2320007001 ), Fundamental Research Funds for the Central Universities under Grants (No. WK2320000048 and No. WK2320000056 ) and USTC Tang Scholar, which are greatly acknowledged.

Tilgjengelig fra: 2024-01-08 Laget: 2024-01-08 Sist oppdatert: 2024-01-08bibliografisk kontrollert
Li, Y. Z., Ingason, H., Blom, J., Arvidson, M. & Försth, M. (2024). Mechanisms and performance of different fixed fire fighting systems in tunnels – summary of laboratory and tunnel fire tests.
Åpne denne publikasjonen i ny fane eller vindu >>Mechanisms and performance of different fixed fire fighting systems in tunnels – summary of laboratory and tunnel fire tests
Vise andre…
2024 (engelsk)Rapport (Annet vitenskapelig)
Abstract [en]

This report presents both small scale laboratory tests and tunnel fire tests carried out in a FORMAS project. Four series of small scale laboratory tests were conducted to obtain the material properties, burning properties, water spray distributions, and spray droplet size distributions. The main efforts were, by adopting the Froude scaling, seven series of tests conducted in a about 50 m long container tunnel with a scale of 1 to 3. This report presents results on the influence of low pressure, medium pressure and high pressure water-based fixed fire fighting systems (FFFSs) on fire development, fire spread to adjacent vehicles, structural protection, tenability, smoke control, spray deflection and spray resistances. The focus is to compare the performance of three default FFFSs and to evaluate the efficiency of each of the FFFS. The results show that the default low pressure FFFS performs well in term of suppressing the fire development, preventing the fire spread to nearby vehicles, providing tenable conditions for evacuation and rescue service, protecting tunnel structure and easing the problem with spray deflection due to tunnel ventilation. The default high pressure FFFS is usually on the opposite side while the default medium pressure FFFS usually lie in between.

Publisher
s. 75
Serie
RISE Rapport ; 2024:22
Emneord
tunnel fire, fixed fire fighting system, fire suppression, fire spread, ventilation, smoke control, deflection, ventilation resistance, structural protection
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-72327 (URN)978-91-89896-70-3 (ISBN)
Forskningsfinansiär
Swedish Research Council Formas
Tilgjengelig fra: 2024-03-15 Laget: 2024-03-15 Sist oppdatert: 2024-04-05bibliografisk kontrollert
Li, Y. Z., Svensson, R., Wahlqvist, J., Van Hees, P. & Ingason, H. (2024). Numerical modelling of water sprays and fire suppression in tunnels.
Åpne denne publikasjonen i ny fane eller vindu >>Numerical modelling of water sprays and fire suppression in tunnels
Vise andre…
2024 (engelsk)Rapport (Annet vitenskapelig)
Abstract [en]

This work aims to validate numerical modelling of water sprays against experiments carried out in this project. The focus has been on the influence of ventilation on water distributions on the tunnel floor, the influence of water sprays on control of smoke flow, and the modelling of pool fires and crib fires. Besides, full scale tunnel fires with FFFS in tunnels using longitudinal ventilation and point extraction ventilation systems are simulated and compared, as well recommendations for numerical modelling of such scenarios.

Publisher
s. 117
Serie
RISE Rapport ; 2024:23
Emneord
tunnel fire, water spray, FFFS, smoke control, water distribution, pyrolysis modelling, ventilation
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-72328 (URN)978-91-89896-71-0 (ISBN)
Forskningsfinansiär
Swedish Research Council Formas, 2019-00521
Merknad

The work is a part of the project “Mechanisms and performance of different fixed fire fighting systems (FFFS) in tunnels” funded by Swedish Research Council FORMAS (2019-00521), which is gratefully acknowledged.

Tilgjengelig fra: 2024-03-15 Laget: 2024-03-15 Sist oppdatert: 2024-04-05bibliografisk kontrollert
Sjöström, J., Sokoti, H., Li, Y. Z. & Brandon, D. (2024). Pyrolysis and thermal properties of wood and high-density polyethylene.
Åpne denne publikasjonen i ny fane eller vindu >>Pyrolysis and thermal properties of wood and high-density polyethylene
2024 (engelsk)Rapport (Annet vitenskapelig)
Abstract [en]

Sample tests were conducted to obtain thermal and kinematic parameters for wood and high-density polyethylene (HDPE) that were used in a series of intermediate scale tunnel fire tests with and without water-based fire suppressions systems. The thermal properties were measured using Transient Plane Source (TPS) and Transient Line Source (TLS). The pyrolysis kinetics parameters were tested based on Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). Different methods were used to obtain pyrolysis kinetics parameters. Different oxygen concentrations exposed to samples were tested and the results showed its significant influence in the charring process.

Publisher
s. 31
Serie
RISE Rapport ; 2024:24
Emneord
TGA, DSC, wood, HDPE, thermal property, pyrolysis kinematic parameters
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-72460 (URN)978-91-89896-72-7 (ISBN)
Forskningsfinansiär
Swedish Research Council Formas, 2019-00521
Merknad

The work is part of the project “Mechanisms and performance of different fixed fire fighting systems in tunnels” funded by Swedish Research Council FORMAS (2019-00521)

Tilgjengelig fra: 2024-03-27 Laget: 2024-03-27 Sist oppdatert: 2024-04-09bibliografisk kontrollert
Hynynen, J., Quant, M., Pramanik, R., Olofsson, A., Li, Y. Z., Arvidson, M. & Andersson, P. (2023). Electric Vehicle Fire Safety in Enclosed Spaces.
Åpne denne publikasjonen i ny fane eller vindu >>Electric Vehicle Fire Safety in Enclosed Spaces
Vise andre…
2023 (engelsk)Rapport (Annet vitenskapelig)
Abstract [en]

Lately, concerns regarding fires in electric vehicles in enclosed spaces such as in road tunnels and parking garages have been raised and there are indications that parking of electric vehicles may be prohibited in some spaces. For the success of electromobility and the transition from fossil to renewable fuels, it is important to understand the risks and consequences of fires in electric vehicles and to provide technical solutions if necessary, so as not to hinder the widespread adoption of electric vehicles.

In this work, a literature review on fires in vehicles has been conducted. The focus was on fires in enclosed spaces involving electric vehicles. A comprehensive risk assessment of electric vehicle fires was performed using systematic hazard identification. In addition, a workshop with representatives from three Swedish fire and rescue services was carried out to evaluate the emergency rescue sheets/response guides.

The main conclusions are; That statistics regarding vehicle fires need to be improved, as of today the root causes of fires are missing in the data, which could potentially result in non-fact based regulations; The data studied in this work does not imply that fires in electric vehicles are more common than fires in internal combustion engine vehicles; Fires in electric vehicles and internal combustion engine vehicles are similar in regards to the fire intensity and peak heat release rates. 

The most effective risk reductions measures on vehicle level, to decrease the number of fires in EVs, could not be defined based on that relevant data on the root causes of fires in EVs are currently not publicly accessible. The most effective risk reduction measures, to limit fire spread, on infrastructure level were the use of fire sprinkler systems, fire detection systems (early detection) and increased distance between parked vehicles.

Publisher
s. 79
Serie
RISE Rapport ; 2023:42
Emneord
Electric vehicle, fire safety, enclosed space, parking garage, vehicle fire, field experience, hazard identification
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-64248 (URN)978-91-89757-90-5 (ISBN)
Tilgjengelig fra: 2023-03-21 Laget: 2023-03-21 Sist oppdatert: 2023-11-02bibliografisk kontrollert
He, K., Li, Y. Z., Ingason, H. & Cheng, X. (2023). Fire spread among multiple vehicles in tunnels using longitudinal ventilation. Tunnelling and Underground Space Technology, 133, Article ID 104967.
Åpne denne publikasjonen i ny fane eller vindu >>Fire spread among multiple vehicles in tunnels using longitudinal ventilation
2023 (engelsk)Inngår i: Tunnelling and Underground Space Technology, ISSN 0886-7798, E-ISSN 1878-4364, Vol. 133, artikkel-id 104967Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The characteristics of fire spread among multiple vehicles in tunnels using longitudinal ventilation were investigated by analyzing the experimental data from a series of fire tests in a 1:15 scale tunnel. Further, a simple theoretical model for gas temperature in a tunnel with multiple fire sources was proposed and used in analysis of the experimental data. The results showed that, for objects (wood piles) placed at a same separating distance downstream of the fire, the fire spread occurred faster and faster along the tunnel. Validation of the simplified temperature model for multiple fire sources was made against both model and full-scale tunnel fire tests. The model was further used to predict the critical conditions for fire spread to the second and third objects. Comparisons with the test data showed that average excess temperature of 465 K (or an equivalent incident heat flux of 18.7 kW/m2) could be used as the criterion for fire spread, and this was verified further by other model-scale tests and full-scale tests. The results showed that the critical fire spread distance monotonously increases with the heat release rate, and decreases with the tunnel perimeter. For multiple fire sources with equivalent heat release rates, as the separation distance between the first two fire sources increases, the critical fire spread distance from the second fire source to the third fire source decreases, but the total fire spread distance from the first fire source to the third one increases. If the total heat release rate at the site of a downstream fire source is greater than that at the former fire source, the critical fire spread distance becomes longer.

sted, utgiver, år, opplag, sider
Elsevier, 2023
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-64962 (URN)10.1016/j.tust.2022.104967 (DOI)
Merknad

This project was financially supported by the Tunnel and Underground Safety Center (TUSC), and the Swedish Fire Research Board (BRANDFORSK), which are greatly acknowledged. 

Highlights:•Fire spread in tunnels using longitudinal ventilation was studied.•A simplified temperature model for tunnel with multiple fire sources was proposed.•Criterion for fire spread to two nearby vehicles in tunnel was investigated.•Critical fire spread distance in a tunnel with multiple fire sources was discussed.

 

 

Tilgjengelig fra: 2023-06-09 Laget: 2023-06-09 Sist oppdatert: 2023-06-12bibliografisk kontrollert
Guo, Q., Li, Y. Z., Ingason, H., Yan, Z. & Zhu, H. (2023). Numerical study on thermally driven smoke flow characteristics in long tunnels under natural ventilation. International journal of thermal sciences, 192, Article ID 108379.
Åpne denne publikasjonen i ny fane eller vindu >>Numerical study on thermally driven smoke flow characteristics in long tunnels under natural ventilation
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2023 (engelsk)Inngår i: International journal of thermal sciences, ISSN 1290-0729, E-ISSN 1778-4166, Vol. 192, artikkel-id 108379Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The paper focuses on the flow structures and mass flow rates of thermally driven smoke flows induced by fires in long transportation tunnels under natural ventilation. The important influencing factors including heat release rate (HRR), tunnel width and height, are taken into consideration. The mechanism of the smoke flow movement is explored. The results show that for a fire in a long naturally ventilated transportation tunnel, there exists a critical point which is dependent on HRR and tunnel geometry. This critical point is defined as the location where the smoke layer thickness and the outgoing mass flow rate increase towards it and decrease after it. Further, it is found that the critical point moves farther away from the fire source in a wider or higher tunnel, while it lies closer to the fire source for a higher HRR. A correlation is proposed to estimate the location of the critical point. The outgoing mass flow rates along the tunnel are calculated using the two-layer flow model and well-mixed flow model of thermally driven flows, and the results indicate that these models produce satisfactory predictions of the mass flow rates if the vertical temperature profile is known. © 2023 The Authors

sted, utgiver, år, opplag, sider
Elsevier Masson s.r.l., 2023
Emneord
Critical point, Long tunnel, Mass flow rate, Smoke flow structure, Tunnel fire, Flow rate, Flow structure, Mass transfer, Smoke, Ventilation, Heat release, Long tunnels, Mass-flow rate, Natural ventilation, Release rate, Smoke flows, Thermally driven, Tunnel fires, Fires
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-64422 (URN)10.1016/j.ijthermalsci.2023.108379 (DOI)2-s2.0-85154579409 (Scopus ID)
Merknad

Correspondence Address: Y.Z. Li; Fire and Safety, RISE Research Institutes of Sweden, Borås, Box 857, SE-501 15, Sweden; email: yingzhen.li@ri.se;  The author(s) would like to acknowledge the Tunnel and Underground Safety Center (TUSC) for the financial support. This work was also financially supported by National Natural Science Foundation of China ( 52208408 ), Key Laboratory of Large Structure Health Monitoring and Control in Hebei Province ( KLLSHMC2101 ) and Taiyuan University of Science and Technology ( 20232014 ) in China.

Tilgjengelig fra: 2023-05-11 Laget: 2023-05-11 Sist oppdatert: 2023-06-08bibliografisk kontrollert
Li, Y. Z., Lönnermark, A., Gehandler, J. & Ingason, H. (Eds.). (2023). Proceedings from the Tenth International Symposium on Tunnel Safety and Security. Paper presented at Tenth International Symposium on Tunnel Safety and Security. STAVANGER, NORWAY, APRIL 26-28, 2023.
Åpne denne publikasjonen i ny fane eller vindu >>Proceedings from the Tenth International Symposium on Tunnel Safety and Security
2023 (engelsk)Konferanseproceedings (Fagfellevurdert)
Abstract [en]

This publication includes the Proceedings of the 10th International Symposium on Tunnel Safety and Security (ISTSS) held in Stavanger, Norway, April 26-28, 2023. The Proceedings include 45 papers and 16 posters. The papers were presented in 16 different sessions, i.e., Keynote sessions, Alternative Fuel Vehicle Safety, Risk Management & Explosion, Digitization, Explosion, Poster Corner, Ventilation 1&2, Fixed Fire Fighting Systems, Tenability and Evacuation, Emergency Management, Evacuation, Safety Management, Fire Dynamics and Resistance. Each day was opened by invited Keynote Speakers (in total five) addressing broad topics of pressing interest. The Keynote Speakers, selected as leaders in their field, consisted of Ove Njå (University of Stavanger, Norway), Vladimir Molkov (Ulster University, UK), Ulf Lundström (Swedish Transport Administration, Sweden), Mirjam Nelisse (TNO, The Netherlands), and Gunnar Jenssen (SINTEF, Norway). We are grateful that the keynote speakers were able to share their knowledge and expertise with the participants of the symposium.

Publisher
s. 680
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-67532 (URN)978-91-89757-89-9 (ISBN)
Konferanse
Tenth International Symposium on Tunnel Safety and Security. STAVANGER, NORWAY, APRIL 26-28, 2023
Tilgjengelig fra: 2023-10-16 Laget: 2023-10-16 Sist oppdatert: 2023-11-29bibliografisk kontrollert
Zhao, S., Yang, H., Li, Y. Z., Ingason, H. & Liu, F. (2023). Theoretical and numerical study on smoke descent during tunnel fires under natural ventilation condition. Tunnelling and Underground Space Technology, 142, Article ID 105414.
Åpne denne publikasjonen i ny fane eller vindu >>Theoretical and numerical study on smoke descent during tunnel fires under natural ventilation condition
Vise andre…
2023 (engelsk)Inngår i: Tunnelling and Underground Space Technology, ISSN 0886-7798, E-ISSN 1878-4364, Vol. 142, artikkel-id 105414Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The smoke stratification and the smoke descent along a tunnel are of the utmost importance for personnel evacuation. The paper investigates the smoke descent along a tunnel during a naturally ventilated tunnel fire. A theoretical model is developed to predict the smoke depth below the ceiling along the tunnel. A series of numerical simulations of full-scale tunnel fires are conducted to compare with the developed model, and some coefficients such as the entrainment coefficient are determined from the simulation results. The concepts of critical moment and critical distance are proposed to characterize the smoke descent along the tunnel. The results show that as the smoke spreads longitudinally, the smoke depth below the tunnel ceiling continuously increases. The temperature decay along the tunnel due to heat losses and air entrainment at the smoke layer interface is considered as the main parameter for the smoke descent. After the vitiated air returns back to the fire source, the smoke stratification in the entire tunnel will be significantly reduced. The smoke layer depth along the tunnel based on the temperature distribution is relatively stable in the process of smoke development, which is not sensitive to the HRR, but influenced by the tunnel width, and this method could only be used before the critical moment. The outcomes of this study could provide references for a better understanding of smoke movement in naturally ventilated tunnels and provide technical guidelines for fire safety designers.

sted, utgiver, år, opplag, sider
Elsevier Ltd, 2023
Emneord
Air entrainment; Fires; Ventilation; Condition; Critical moment; Natural ventilation; Personnel evacuations; Smoke descent; Smoke layer; Smoke stratification; Stratification; Tunnel fires; Ventilated tunnels; Smoke
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-67456 (URN)10.1016/j.tust.2023.105414 (DOI)2-s2.0-85171775524 (Scopus ID)
Merknad

The authors would like to acknowledge the Tunnel and Underground Safety Center (TUSC) for the financial support. Thanks to Qinghua Guo for the valuable discussions and technical assistance during his stay at RISE. Shengzhong Zhao and Haoran Yang were also financially supported by the National Natural Science Foundation of China (No. 52208115 ), the Natural Science Foundation of Shandong Province (No. ZR2020QE279 ) and Plan of Guidance and Cultivation for Young Innovative Talents of Shandong Province.

Tilgjengelig fra: 2023-10-06 Laget: 2023-10-06 Sist oppdatert: 2023-10-06bibliografisk kontrollert
Ingason, H., Li, Y. Z., Arvidson, M. & Jiang, L. (2022). Fire tests with automatic sprinklers in an intermediate scale tunnel. Fire safety journal, 129, Article ID 103567.
Åpne denne publikasjonen i ny fane eller vindu >>Fire tests with automatic sprinklers in an intermediate scale tunnel
2022 (engelsk)Inngår i: Fire safety journal, ISSN 0379-7112, E-ISSN 1873-7226, Vol. 129, artikkel-id 103567Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

A series of 1:3 intermediate scale tunnel fire tests was performed to investigate the performance of a fully automatic sprinkler system in a road tunnel. The experiments were carried in a container tunnel with scaled geometry, using wood pallets as the fire source to simulate HGV fires. The activation of the sprinklers was simulated by using thermocouples that corresponded to a given Thermal Response Index (RTI) of a sprinkler bulb or a link. A total of 12 tests were carried out with varying longitudinal velocities (0.8–1.7 m/s), sprinkler activation temperatures (68–141 °C), water densities (2.9–8.7 mm/min) and types of arrangement of the fuel. The activation times, number of activated sprinklers, maximum heat release rates and other key parameters are presented and analyzed. The results show that the water density plays a key role in the performance of the automatic sprinkler systems tested. A high tunnel ventilation velocity, low water density and low sprinkler activation temperature are not recommended. © 2022 The Authors

sted, utgiver, år, opplag, sider
Elsevier Ltd, 2022
Emneord
Activation, Automatic sprinkler, Model scale, Tunnel fire, Tunnel velocity, Chemical activation, Fires, Flammability testing, Sprinkler systems (irrigation), Thermocouples, Activation temperatures, Fire tests, Performance, Road tunnel, Sprinkler activation, Tunnel fires, Water density, Hose
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-58999 (URN)10.1016/j.firesaf.2022.103567 (DOI)2-s2.0-85127092273 (Scopus ID)
Merknad

Funding details: Svensk Kärnbränslehantering, SKB; Funding details: Trafikverket; Funding text 1: The research was sponsored by the Tunnel and Underground Safety Center (TUSC) with additional funding from the Swedish Transport Administration (STA). The financiers of TUSC are the Swedish Transport Administration (STA), the Swedish Fortifications Agency, the Swedish Nuclear Fuel and Waste Management Company (SKB), and RISE Research Institutes of Sweden. Thanks to Ulf Lundstr?m at STA who contributed extensively to the discussion and preparation for this work and the technical staff at RISE who made it possible to perform the tests.; Funding text 2: The research was sponsored by the Tunnel and Underground Safety Center (TUSC) with additional funding from the Swedish Transport Administration (STA) . The financiers of TUSC are the Swedish Transport Administration (STA), the Swedish Fortifications Agency, the Swedish Nuclear Fuel and Waste Management Company (SKB), and RISE Research Institutes of Sweden. Thanks to Ulf Lundström at STA who contributed extensively to the discussion and preparation for this work and the technical staff at RISE who made it possible to perform the tests.

Tilgjengelig fra: 2022-06-13 Laget: 2022-06-13 Sist oppdatert: 2023-06-08bibliografisk kontrollert
Organisasjoner
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0001-7744-2390
v. 2.41.0