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Lindberg, T., Johansson, F., Peterson, A. & Tapani, A. (2021). Discrete Event Simulation of Bus Terminals: A Modular Approach with a High Spatial Resolution. Journal of Advanced Transportation, 2021, Article ID 8862893.
Open this publication in new window or tab >>Discrete Event Simulation of Bus Terminals: A Modular Approach with a High Spatial Resolution
2021 (English)In: Journal of Advanced Transportation, ISSN 0197-6729, E-ISSN 2042-3195, Vol. 2021, article id 8862893Article in journal (Refereed) Published
Abstract [en]

Interchange stations with their many connecting modes and lines are central for a high-qualitypublic transport system. Bus access at the station needs to operate reliably and efficiently in order to prevent congestion and queues. To this end, a conceptual simulation model for evaluation of bus terminal operations is presented in this paper. It is based on discrete event simulation and able to describe the detailed movements and interactions that occur between vehicles at larger terminals. The model has a modular approach, where common spatial sections at terminals are represented bymodules that can be easily combined into many different terminal layouts. An implementation of the model is presented and, as a first sensitivity test, applied in a numerical experiment representingNorrköping interchange station in Sweden. The results indicate that the model can be a useful tool in planning processes.

Place, publisher, year, edition, pages
Hindawi Limited, 2021
National Category
Transport Systems and Logistics
Identifiers
urn:nbn:se:vti:diva-15929 (URN)10.1155/2021/8862893 (DOI)2-s2.0-85100604129 (Scopus ID)
Available from: 2021-03-03 Created: 2021-03-03 Last updated: 2022-10-12Bibliographically approved
Liu, C., Tapani, A., Kristoffersson, I., Rydergren, C. & Jonsson, D. (2020). Appraisal of cycling infrastructure investments using a transport model with focus on cycling. Case Studies on Transport Policy
Open this publication in new window or tab >>Appraisal of cycling infrastructure investments using a transport model with focus on cycling
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2020 (English)In: Case Studies on Transport Policy, ISSN 2213-624X, E-ISSN 2213-6258Article in journal (Refereed) Published
Abstract [en]

Cost-benefit analysis (CBA) for cycling infrastructure investments are less sophistically developed compared to the ones for private cars and public transport, and one of main reasons is the lack of “well-developed” transport models for cycling. In this study, a dedicated transport model for cycling is used to appraise cycling infrastructure investments in Stockholm, Sweden. The model captures the impact of a change in cycling infrastructure on cycling route choice, mode choice, destination choice and trip generation and calculates cycling flow on link level. the generalised cost measure defined in the route choice model captures the impact of cycling infrastructure. Results suggest that although cycling flow on the links with investment may increase substantially, only a small share comes from modal shift and thus the external effects such as reducing car congestion and emissions are marginal. For all three scenarios investigated, over 97% of the benefits measured in the unit of generalised cost belong to the existing cyclists. The route choice model does not minimize travel time but generalised cost which also measures health, safety benefits and other possible benefits that may be considered by the cyclists when they choose to cycle. In fact, travel time saving benefits of the investments evaluated in this paper are all negative. The existing effect evaluation models therefore need to be adjusted to be more consistent with the transport model.

Place, publisher, year, edition, pages
Elsevier Ltd, 2020
National Category
Transport Systems and Logistics
Identifiers
urn:nbn:se:vti:diva-15874 (URN)10.1016/j.cstp.2020.11.003 (DOI)2-s2.0-85097085357 (Scopus ID)
Available from: 2020-12-29 Created: 2020-12-29 Last updated: 2020-12-29Bibliographically approved
Grumert, E. & Tapani, A. (2020). Bottleneck mitigation through a variable speed limit system using connected vehicles. Transportmetrica A: Transport Science, 16(2), 213-233
Open this publication in new window or tab >>Bottleneck mitigation through a variable speed limit system using connected vehicles
2020 (English)In: Transportmetrica A: Transport Science, ISSN 2324-9935, E-ISSN 2324-9943, Vol. 16, no 2, p. 213-233Article in journal (Refereed) Published
Abstract [en]

Variable speed limit (VSL) systems are used to improve the traffic conditions by adjusting the speed limits based on the current traffic situation. Advances in vehicle technology have made it possible to use connected vehicles in VSL systems. Connected vehicles can continuously transmit information about their speed and location, which can be used to estimate the current traffic conditions at arbitrary locations. In this study, we propose a VSL system based on connected vehicles. The aim is to also allow application of VSLs for non-recurrent bottleneck mitigation at arbitrary locations, unlike today's systems which require densely placed detectors or are limited to beforehand known bottleneck locations. The proposed system is evaluated by microscopic traffic simulation. The results indicate that the VSL system manage to improve traffic efficiency in a simulated incident scenario.

Place, publisher, year, edition, pages
Taylor and Francis Ltd., 2020
Keywords
Connected vehicle, Variable speed limit, Bottleneck, Evaluation (assessment), Simulation, Micro
National Category
Infrastructure Engineering
Research subject
20 Road: Traffic engineering, 22 Road: Traffic control and traffic information
Identifiers
urn:nbn:se:vti:diva-13453 (URN)10.1080/23249935.2018.1547332 (DOI)2-s2.0-85057525365 (Scopus ID)
Available from: 2018-12-28 Created: 2018-12-28 Last updated: 2022-06-16Bibliographically approved
Liu, C., Tapani, A., Kristoffersson, I., Rydergren, C. & Jonsson, D. (2020). Development of a large-scale transport model with focus on cycling. Transportation Research Part A: Policy and Practice, 134, 164-183
Open this publication in new window or tab >>Development of a large-scale transport model with focus on cycling
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2020 (English)In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 134, p. 164-183Article in journal (Refereed) Published
Abstract [en]

This study presents a transport model to better model cycling demand. The model improves modelling of cycling in several ways compared to a conventional transport model. First, it uses a detailed bicycle network containing information about existing bicycle infrastructure. Second, generalised cost measures based on different bicycle route choice models are calculated and compared to evaluate how to best represent the impact of bicycle infrastructure in the model. Third, the model utilizes a refined zone system with smaller zones of size 250 m × 250 m. Using these smaller zones, more short-distance tours are included in the model, and these are predominantly walking and cycling trips. Fourth, the model considers cycling also as an access mode choice to public transport. Therefore, the model treats cycling and public transport as both competing and complementary modes. Results show that the model captures detailed individual heterogeneity in cycling demand for different trip purposes. Impacts of bicycle infrastructure, land use characteristics and individual/household socio-demographics are investigated. Detailed individual level travel time and generalised cost are derived for cyclists of different socio-demographics. The result highlights the importance of choosing a good measure of generalised cost, given that different bicycle route choice models result in different effects of bicycle infrastructure. In future applications, the model can be used to evaluate proposed bicycle investments regarding their impact on link flow, bicycle route choice, modal shift and generation of completely new tours. The model can also be a powerful tool in a cost-benefit analysis of bicycle investments.

Place, publisher, year, edition, pages
Elsevier, 2020
Keywords
Transport network, Bicycle, Mathematical model, Cycling infrastructure, Route (itinerary), Choice, Modal choice, Journey purpose, Land use, Journey time, Cost
National Category
Transport Systems and Logistics
Research subject
10 Road: Transport, society, policy and planning, 113 Road: Cycling, walking and moped transport
Identifiers
urn:nbn:se:vti:diva-15082 (URN)10.1016/j.tra.2020.02.010 (DOI)2-s2.0-85079644007 (Scopus ID)
Available from: 2020-03-09 Created: 2020-03-09 Last updated: 2020-04-29Bibliographically approved
Lindberg, T., Johansson, F., Peterson, A. & Tapani, A. (2020). Microsimulation Of Bus Terminals: A Case Study From Stockholm. In: K.-H. Bae, B. Feng, S. Kim, S. Lazarova-Molnar, Z. Zheng, T. Roeder, and R. Thiesing (Ed.), Proceedings of the 2020 Winter Simulation Conference: . Paper presented at 2020 Winter Simulation Conference.
Open this publication in new window or tab >>Microsimulation Of Bus Terminals: A Case Study From Stockholm
2020 (English)In: Proceedings of the 2020 Winter Simulation Conference / [ed] K.-H. Bae, B. Feng, S. Kim, S. Lazarova-Molnar, Z. Zheng, T. Roeder, and R. Thiesing, 2020Conference paper, Published paper (Other academic)
Abstract [en]

When new bus terminals are being planned or existing ones redesigned, suitable tools that are able todescribe the complex situation at a terminal are needed. Using microsimulation, vehicle movements andinteractions can be simulated and the congestion and capacity of a terminal can be evaluated. In this study,a discrete event simulation model is used in a case study of the Slussen bus terminal in Stockholm, Sweden.The model is calibrated and validated with empirical data that are automatically collected at the terminal.Already with this limited amount of data, the parameter time per boarding passenger can be calibrated witha relative error less than 1 % and the validation gives further insights into the data needed for calibrationof a terminal simulation model.

Keywords
Bus stop, Passenger station, Simulation, Pedestrian, Mathematical model
National Category
Transport Systems and Logistics
Research subject
10 Road: Transport, society, policy and planning, 111 Road: Public transport
Identifiers
urn:nbn:se:vti:diva-16066 (URN)10.1109/WSC48552.2020.9383876 (DOI)2-s2.0-85103889145 (Scopus ID)
Conference
2020 Winter Simulation Conference
Available from: 2021-03-11 Created: 2021-03-11 Last updated: 2022-10-12Bibliographically approved
Liu, C., Tapani, A., Kristoffersson, I., Rydergren, C. & Jonsson, D. (2019). En transportmodell med fokus på cykeltrafik: modellutveckling och scenarioanalyser. Linköping: Statens väg- och transportforskningsinstitut
Open this publication in new window or tab >>En transportmodell med fokus på cykeltrafik: modellutveckling och scenarioanalyser
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2019 (Swedish)Report (Other academic)
Alternative title[en]
A transport model with focus on bicycle trips : model development and scenario analysis
Abstract [sv]

Ökad andel resor med hållbara färdmedel är en förutsättning för att kombinera fortsatt tillväxt med minskad resursförbrukning och miljöpåverkan. I många europeiska städer har cykel blivit ett alltmer populärt färdmedel under de senaste decennierna. Dagens storskaliga transportmodeller, som utgör viktiga verktyg för utvärderingar och samhällsekonomiska analyser, är dock oftast fokuserade på modellering av resor med bil eller kollektivtrafik. Den här rapporten presenterar en tur-baserad transportmodell med syfte att bättre modellera cykelresor. Nyheterna i denna modell är bland annat ett detaljerat cykelnät som innehåller mer än 200 000 länkar och att modellen nyttjar en mer detaljerad zonindelning. Jämfört med nuvarande verktyget för samhällsekonomisk analys av cykelåtgärder, GCkalk, beskriver modellen ett fullständigt utbud och efterfrågan för cykel på detaljerad geografisk nivå. Modellen har skattats på data från den senaste resvaneundersökningen i Stockholms län från 2015 och representerar därmed observerat resebeteende. Modellen beaktar även cykel som anslutningsfärdmedel till resor med kollektivtrafik. Därigenom behandlar modellen cykel- och kollektivtrafik både som konkurrerande och som komplementära färdmedel och modellen kan utvärdera effekten av en förbättring av cykelinfrastrukturen på både enbart cykelresande och på cykel som anslutningsfärdmedel till kollektivtrafikstationer. Modellen är validerad mot cykelräkningar i Stockholm stad från september och oktober 2015. Modellen har testats på sex scenarier valda från Stockholms stads investeringsplan. Resultaten visar att investeringarna har en begränsad effekt på överflyttning mellan färdmedel och en måttlig effekt på befintliga cyklisters ruttval, restid och generaliserad kostnad.

Abstract [en]

Encouraging the use of active travel modes such as walking and cycling is vital for ensuring a sustainable urban development. In many European metropolitan areas, cycling is becoming increasingly popular within the recent decades. On the other hand, large-scale transport models, which serve as the main tools for policy evaluation and cost-benefit analysis, are often designed for modelling motorised travel modes such as private car and public transport. This study presents a tourbased transport model to better model cycling demand and supply. First, it uses a detailed bicycle network containing more than 200,000 links, covering the whole Greater Stockholm Area. Second, the model utilizes a refined zoning system with totally 5 808 zones each of the size of 250 m×250 m covering the entire Greater Stockholm Area. Third, the model is estimated on the newest Stockholm travel survey 2015, and therefore the model can represent travel behaviour that is up-to-date. In addition to the improvements mentioned above, the model also considers cycling as an access travel mode to a trip by public transport. Therefore, the model treats cycling and public transport as both competing and complementary modes, and the model is capable of evaluating the impact of an improvement in bicycle infrastructure on cycling, as well as on cycling to public transport stations. The model is then validated against bicycle count data from the City of Stockholm. Six scenarios are tested according to the investment plan from the City of Stockholm. The results show that the investments have a limited effect on modal shift but a moderate effect on the existing cyclists' route choice, travel time and generalised cost.

Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2019. p. 144
Series
VTI rapport, ISSN 0347-6030 ; 1007
Keywords
Bicycle, Cycling, Journey, Forecast, Model (not math), Calculation
National Category
Transport Systems and Logistics
Research subject
10 Road: Transport, society, policy and planning, 113 Road: Cycling, walking and moped transport
Identifiers
urn:nbn:se:vti:diva-13706 (URN)
Available from: 2019-04-18 Created: 2019-04-18 Last updated: 2020-09-14Bibliographically approved
Grumert, E., Bernhardsson, V., Ekström, J., Gundlegård, D., Ringdahl, R. & Tapani, A. (2019). Variabla hastighetsgränser för Stockholms motorvägsnät: effekter av alternativa algoritmer och möjligheter till styrning genom estimerade trafiktillstånd. Linköping: Statens väg- och transportforskningsinstitut
Open this publication in new window or tab >>Variabla hastighetsgränser för Stockholms motorvägsnät: effekter av alternativa algoritmer och möjligheter till styrning genom estimerade trafiktillstånd
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2019 (Swedish)Report (Other academic)
Alternative title[en]
Variable speed limits for Stockholm’s urban motorways : effects of different algorithms and the possibility to control by the use of estimated traffic states.
Abstract [sv]

Variabla hastighetsgränser är väl utbrett på Stockholms stadsnära motorvägar och en del av Stockholms Motorway Control System (MCS). Målet med dagens system är att minska risken för olyckor och följdolyckor vid låga hastigheter, trafikstockningar m.m. Detta görs genom att mäta medelhastigheten med hjälp av fasta detektorer och uppdatera hastigheten som visas på variabla meddelandeskyltar utifrån rådande trafiktillstånd. I och med att efterfrågan på resor i Stockholm under rusningstid överstiger den tillgängliga kapaciteten i vägnätet är behovet av ett effektivt trafiksystem stort. Variabla hastighetsgränser kan bidra till ökad framkomlighet, men då dagens system har som målsättning att öka säkerheten är effekter som leder till ökad framkomlighet begränsade. Dessutom finns det i dagens system ett stort beroende av fungerande detektorer som mäter trafiktillståndet så korrekt som möjligt för att valet av hastighet ska kunna bestämmas på ett effektivt sätt.

Syftet med den här rapporten är att undersöka alternativa styralgoritmer för att bestämma variabla hastighetsgränser på Stockholms motorvägsnät. Målet är att öka framkomligheten jämfört med dagens system. Två olika sträckor med olika komplexitet, trafiksituation och problematik studeras. Valet av studerade styralgoritmer för de olika sträckorna väljs för att på bästa sätt motverka den problematiken som uppstår på de specifika sträckorna. Därmed kan val av algoritmer komma att skilja sig åt beroende på sträcka. I projektet utvärderas också om estimering av trafiktillståndet kan användas för att förbättra informationsflödet till algoritmerna då detektorer inte fungerar som de ska eller helt saknas, vilket i sin tur kan leda till förbättrad anpassning av de variabla hastighetsgränserna. Detta görs av för en av de studerade sträckorna. Styralgoritmerna utvärderas med mikroskopisk trafiksimulering och metoden utvecklad i projektet Mobile Millenium Stockholm (MMS), som bygger på en makroskopisk trafikflödesmodell och Kalman filtrering, används för estimering av trafiktillståndet.

Abstract [en]

Variable speed limits are commonly used on Stockholm’s urban motorways, and it is part of the Stockholm Motorway Control System (MCS). The goal of today’s system is to reduce the risk of accidents during congested conditions, traffic jams etc. This is done by updating the speed limits shown on variable message signs based on a measured average speed at fixed detectors. As the demand for travel in Stockholm during peak-hours exceeds the available capacity in the road network, the need for an efficient traffic system is high. Variable speed limit systems have the possibility to contribute to increased efficiency, but since today’s system aims to increase safety, effects that lead to increased efficiency are limited. Further, in todays’ variable speed limit systems there are a large dependency of precise and available measurements from stationary detectors to be able to display speed limits that reflects the current traffic conditions. The purpose of this report is to investigate alternative control algorithms to decide on the variable speed limits to be displayed at variable message signs on the urban motorway of Stockholm.

The goal is to increase efficiency compared to today's system. Two different road stretches with different complexity and different traffic conditions, resulting in two different types of congestion, are studied. Thereby, the studied control algorithms on the two road stretches are chosen based on the possibility of solving a specific problematic traffic situation in the best way. Hence, the studied control algorithms might differ for the two road stretches. Furthermore, for one of the roads stretches it is investigated if estimation of the traffic state can be used as input to the control algorithm as a complement to missing and erogenous measurements from stationary detectors in order to improve the calculations of the variable speed limits. The control algorithms are evaluated with microscopic traffic simulation and the method developed in the project Mobile Millenium Stockholm (MMS), using a macroscopic traffic flow model together with a Kalman filter, is used for estimation of the traffic state.

Place, publisher, year, edition, pages
Linköping: Statens väg- och transportforskningsinstitut, 2019. p. 52
Series
VTI rapport, ISSN 0347-6030 ; 1006
Keywords
Variable speed limit, Algorithm, Traffic flow, Traffic, Simulation, Micro, Macro, Motorway, Traffic control
National Category
Transport Systems and Logistics
Research subject
20 Road: Traffic engineering, 25 Road: Traffic theory
Identifiers
urn:nbn:se:vti:diva-13704 (URN)
Available from: 2019-04-08 Created: 2019-04-08 Last updated: 2020-09-14Bibliographically approved
Lindberg, T., Peterson, A. & Tapani, A. (2018). A simulation model for assessment and evaluation of bus terminal design. In: : . Paper presented at Conference on Advanced Systems in Public Transport and TransitData 2018.
Open this publication in new window or tab >>A simulation model for assessment and evaluation of bus terminal design
2018 (English)Conference paper, Published paper (Other academic)
Abstract [en]

Interchange stations with their connections between modes and lines are central for a high quality public transport system. Bus access at the station needs to operate reliably and efficiently in order to prevent congestion and queues. Here, a discrete event simulation model of vehicle movements and interactions at bus terminals is developed and implemented. The model has a modular approach, where common spatial sections at terminals are represented by modules that can be combined into various terminal layouts. These modules describe the events a vehicle may go through in a particular section of the terminal, such as arriving to a bus stop or stopping at a traffic light at the exit. The model can be used in planning processes, both for new terminals and redesign of existing ones, and is able to describe the detailed movements and interactions between vehicles that occur at larger terminals. The model is tested in a numerical experiment representing Norrköping interchange station in Sweden. The experiment shows that the model is able to evaluate and compare different scenarios and can thus be a useful tool in planning processes.

 

Keywords
Interchange (public transport), Simulation, Bus, Accessibility, Mathematical model, Evaluation (assessment)
National Category
Transport Systems and Logistics
Research subject
10 Road: Transport, society, policy and planning, 111 Road: Public transport; 20 Road: Traffic engineering, 25 Road: Traffic theory
Identifiers
urn:nbn:se:vti:diva-13985 (URN)
Conference
Conference on Advanced Systems in Public Transport and TransitData 2018
Available from: 2019-06-25 Created: 2019-06-25 Last updated: 2020-01-17Bibliographically approved
Grumert, E., Tapani, A. & Ma, X. (2018). Characteristics of variable speed limit systems. European Transport Research Review, 10(2), Article ID 21.
Open this publication in new window or tab >>Characteristics of variable speed limit systems
2018 (English)In: European Transport Research Review, ISSN 1867-0717, E-ISSN 1866-8887, Vol. 10, no 2, article id 21Article in journal (Refereed) Published
Abstract [en]

The control algorithm used for deciding on the speed limit in variable speed limit systems is crucial for the performance of the systems. The algorithm is designed to fulfil the purpose of the variable speed limit system, which can be one or several of the following aspects: increasing safety, increasing efficiency and decreasing environmental impacts. Today, many of the control algorithms used in practice are based on fixed thresholds in speed and/or flow. Therefore, they are not necessarily reflecting the current traffic conditions. Control algorithms with a greater level of complexity can be found in the literature. In this paper, four existing control algorithms are investigated to conclude on important characteristics affecting the performance of the variable speed limit system. The purpose of the variable speed limit system and, consequently, the design of the control algorithm differ. Requirements of the investigated control algorithms are that they should be easy to interpret and the execution time should be short. The algorithms are evaluated through microscopic traffic simulation. Performance indicators related to traffic safety, traffic efficiency and environmental impacts are presented. The results show that the characteristics of the variable speed limit system and the design of the control algorithm will have effect on the resulting traffic performance, given that the drivers comply with the variable speed limits. Moreover, the time needed to trigger the system, the duration and the size of speed limit reductions, and the location of the congestion are factors of importance for the performance of variable speed limit systems.

Place, publisher, year, edition, pages
SPRINGER HEIDELBERG, 2018
Keywords
Variable speed limit, Algorithm, Characteristics, Traffic, Micro, Simulation, Traffic flow, Efficiency, Evaluation (assessment), Safety, Emission, Congestion (traffic)
National Category
Transport Systems and Logistics
Research subject
20 Road: Traffic engineering, 22 Road: Traffic control and traffic information; 20 Road: Traffic engineering, 25 Road: Traffic theory
Identifiers
urn:nbn:se:vti:diva-13109 (URN)10.1186/s12544-018-0294-8 (DOI)000434026100001 ()2-s2.0-85047992584 (Scopus ID)
Available from: 2018-09-10 Created: 2018-09-10 Last updated: 2022-04-01Bibliographically approved
Grumert, E. & Tapani, A. (2018). Traffic State Estimation Using Connected Vehicles and Stationary Detectors. Journal of Advanced Transportation, Article ID UNSP 4106086.
Open this publication in new window or tab >>Traffic State Estimation Using Connected Vehicles and Stationary Detectors
2018 (English)In: Journal of Advanced Transportation, ISSN 0197-6729, E-ISSN 2042-3195, article id UNSP 4106086Article in journal (Refereed) Published
Abstract [en]

Real-time traffic state estimation is of importance for efficient traffic management. This is especially the case for traffic management systems that require fast detection of changes in the traffic conditions in order to apply an effective control measure. In this paper, we propose a method for estimating the traffic state and speed and density, by using connected vehicles combined with stationary detectors. The aim is to allow fast and accurate estimation of changes in the traffic conditions. The proposed method does only require information about the speed and the position of connected vehicles and can make use of sparsely located stationary detectors to limit the dependence on the infrastructure equipment. An evaluation of the proposed method is carried out by microscopic traffic simulation. The traffic state estimated using the proposed method is compared to the true simulated traffic state. Further, the density estimates are compared to density estimates from one detector-based method, one combined method, and one connected-vehicle-based method. The results of the study show that the proposed method is a promising alternative for estimating the traffic state in traffic management applications.

Place, publisher, year, edition, pages
WILEY-HINDAWI, 2018
Keywords
Traffic flow, Real time, Traffic control, Traffic concentration, Speed, Estimation, Connected vehicle, Detector
National Category
Transport Systems and Logistics
Research subject
20 Road: Traffic engineering, 23 Road: ITS och traffic
Identifiers
urn:nbn:se:vti:diva-12818 (URN)10.1155/2018/4106086 (DOI)000423031600001 ()2-s2.0-85042641207 (Scopus ID)
Available from: 2018-04-05 Created: 2018-04-05 Last updated: 2018-06-11Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-9635-5233

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