| 41. |
- Adesiyun, Adewole, et al.
(författare)
-
Review and Evaluation of NRAs : Deliverable D2
- 2023
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Connected and Automated Driving (CAD) is an important area of digital technology that will bring disruption to individuals, economies, and societies. Most forms of CAD require some level of infrastructure support for their safe operation. Additional infrastructure and services to support CAD have the potential to improve safety even further, and to bring other benefits such as increased efficiency or reduced congestion. However, the infrastructure requirements from Original Equipment Manufacturer (OEMs) are not always clear, and it is difficult for National Road Authorities (NRAs) to predict and plan for the future levels of support needed for CAD given rapidly evolving technology and uncertain projections of future CAD demand. In addition, there is also a need for better dialogue among NRAs, OEMs and service providers to articulate those requirements and to define a roadmap and responsibilities for achieving safe and smart roads through CAD.The aim of DiREC is to establish a CAV Readiness Framework and a set of toolkits dedicated to CAVs (Connected and Autonomous Vehicles) that incorporates a wide range of components that affect CAD and the ability of highway infrastructure to support it. These components include machine readability of physical infrastructure, digital services, connectivity, in addition to aspects such as governance of the infrastructure and services, and legal and regulatory requirements. Together these components influence the ability of the NRA to become a digital road operator. The DiREC project will thus provide a framework for NRAs, service providers and OEMs to support CAD. It will consolidate and combine standards, research, and recommendations from other projects and extend research into new areas such as creating a common vision for digital twins among NRAs, understanding connectivity and connectivity requirements to support digital services and analysing how these can be met, reviewing the quality management processes around digital data, and documenting existing legal and regulatory frameworks in all areas relating to CAD.
|
|
| 42. |
|
|
| 43. |
- Adesiyun, Adewole, et al.
(författare)
-
Stakeholder Engagement Report : Deliverable D1
- 2023
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The main aim of the DiREC project is developing a common framework to support National Road Authorities (NRAs) to provide better engagement with Original Equipment Manufacturers (OEM) and service providers, identify clearer responsibilities and liabilities, and include tools to calculate the costs and benefits of providing different levels of support to Connected and Automated Vehicles (CAVs). Greater engagement and dialogue are key. By understanding the infrastructure and communications requirements of automated vehicles, and the challenges faced by CAVs in an operational environment, NRAs will be able to strategically plan their networks to support Connected and Automated Driving (CAD) and place themselves in a much stronger position to influence how traffic operates on the network.A proactive approach to liaising with vehicle manufacturers and service providers will also promote NRA involvement in the services that are developing around digital mapping, localisation, navigation and traffic management. By aligning the digital strategies and plans of the NRAs with the requirements of OEMs and CAVs, and by giving direction to service providers, a common framework for CAD will help achieve major cost efficiencies and facilitate economic transformation. It will help optimise the delivery of infrastructure and communications systems on national road networks in support of CAD implementation whilst helping NRAs maintain their influence over CAD activity. In order to facilitate productive interactions with various stakeholders involved with CAVs, WP1 within the DiREC project is dedicated to stakeholder engagement activities. This will ensure that input from different stakeholder categories will be collected and utilized for CAV-ready framework development.
|
|
| 44. |
|
|
| 45. |
- Adolehoume, Amakoe, et al.
(författare)
-
Road safety policies in seven West African countries
- 2001
-
Ingår i: Proceedings of the Conference Road Safety on Three Continents in Pretoria, South Africa, 20-22 September 2000. - Linköping : Statens väg- och transportforskningsinstitut. ; , s. 303-316
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- At the end of 1999, UEMOA, the Economic and Monetary Union for West Africa, launched a study of the road safety situation and management processes in seven of the eight countries of the Union (Benin, Burkina Faso, Cite d'Ivoire, Mali, Niger, Senegal, Togo), in view of formulating Communal Road Safety Policies at the regional level. A team of African and European "experts" was formed to establish a diagnosis on each country as well as a global assessment of the situation in the region, and to draw proposals for action. The final report was published in March 2000 and is now being evaluated by UEMOA and integrated into a wider proposal for transport policies, for presentation at a round table of donors. The present paper does not provide a complete summary of the outcome of the study, but presents a selection of some difficult problems encountered in the countries investigated and directions for possible solutions as seen by the researchers and consultants that took part in the study. Comprehensive proposals and guidelines for Communal Road Safety Policies are not included as they have not officially been accepted by UEMOA yet, but the original report can be requested from this organisation in Ouagadougou. A brief outline of the approach and methodology used is described. More complete methodological guidelines, developed from the experience gathered through the UEMOA study as well as previous ones carried out by Inrets (the French National Institute for Transport and Safety Research) will be published at a later stage.
|
|
| 46. |
- Adolph, Thorsten, et al.
(författare)
-
Comparison of the dummy response in two different restraint system crash tests
- 2014
-
Ingår i: 2014 IRCOBI Conference Proceedings - International Research Council on the Biomechanics of Injury. ; , s. 545-561
-
Konferensbidrag (refereegranskat)abstract
- In the European Project FIMCAR, a proposal for a frontal impact test configuration was developed which included an additional full width deformable barrier (FWDB) test. Motivation for the deformable element was partly to measure structural forces as well as to produce a severe crash pulse different from that in the offset test. The objective of this study was to analyse the safety performance of vehicles:in the full width rigid barrier test (FWRB) andin the full width deformable barrier test (FWDB)In total, 12 vehicles were crashed in both configurations. Comparison of these tests to real world accident data was used to identify the crash barrier most representative of real world crashes. For all vehicles, the airbag visible times were later in the FWDB configuration. This was attributed to the attenuation of the initial acceleration peak, observed in FWRB tests, by the addition of the deformable element. These findings were in alignment with airbag triggering times seen in real world crash data. Also, the dummy loadings were slightly worse in FWDB compared to FWRB tests, which is possibly linked to the airbag firing and a more realistic loading of the vehicle crash structures in the FWDB configuration. Evaluations of the lower extremities have shown a general increasing of the tibia index with the crash pulse severity.
|
|
| 47. |
- Adolph, T., et al.
(författare)
-
Development of compatibility assessments for full-width and offset frontal impact test procedures in FIMCAR
- 2014
-
Ingår i: International Journal of Crashworthiness. - : Informa UK Limited. - 1358-8265 .- 1754-2111. ; 19:4, s. 414-430
-
Tidskriftsartikel (refereegranskat)abstract
- The goal of the project FIMCAR (Frontal Impact and Compatibility Assessment Research) was to define an integrated set of test procedures and associated metrics to assess a vehicle's frontal impact protection, which includes self-And partner-protection. For the development of the set, two different full-width tests (full-width deformable barrier [FWDB] test, full-width rigid barrier test) and three different offset tests (offset deformable barrier [ODB] test, progressive deformable barrier [PDB] test, moveable deformable barrier with the PDB barrier face [MPDB] test) have been investigated. Different compatibility assessment procedures were analysed and metrics for assessing structural interaction (structural alignment, vertical and horizontal load spreading) as well as several promising metrics for the PDB/MPDB barrier were developed.The final assessment approach consists of a combination of the most suitable full-width and offset tests. For the full-width test (FWDB), a metric was developed to address structural alignment based on load cell wall information in the first 40 ms of the test. For the offset test (ODB), the existing ECE R94 was chosen. Within the paper, an overview of the final assessment approach for the frontal impact test procedures and their development is given.
|
|
| 48. |
- Afridi, Amjad, et al.
(författare)
-
Management of municipal street network in Sweden : results from a national survey
- 2024
-
Ingår i: Sammanställning av referat från Transportforum 2024. - Linköping : Statens väg- och transportforskningsinstitut. ; , s. 395-396
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Management of street networks is different from state roads due to its multifunctional role in society. This requires timely maintenance of the street network to improve socioeconomic development. Municipalities in Sweden are responsible for the management of about 42000 km of street network in their jurisdiction. Maintenance budget and resources vary from municipality to municipality depending on their network size, geographical location, and population density. A questionnaire was sent to all 290 municipalities across the country to investigate the street network and pavement management practices at the municipal level. An in-depth interview of 14 municipalities took place afterwards. A total of 51% of responses were officially received to highlight the frequently and infrequently occurring pavement distresses and their causes. Furthermore, the study highlights the maintenance approaches and allocation of budget to manage the street network. Lastly, the study highlights the factors which need to be addressed to improve street network management. Visual assessment of pavements is common and the use of pavement management system (PMS) is not only limited but also lacks pavement performance prediction models. Common pavement distresses are excessive formation of potholes, surface unevenness and alligator distress among the municipalities. Frequent causes of distress include the ageing of the street network, heavy vehicles, patching and high traffic flow. Furthermore, cold climate and population density are important factors in the degradation process. Allocation of maintenance and reconstruction budget is relatively high in municipalities located in the north. Densely populated municipalities have higher taxpayers’ contributions to maintenance and reconstruction. Other major issues are limited resources and maintenance of budget, which adversely affect the maintenance backlog and the choice of maintenance alternatives, ultimately the decision-making. This restricts the use of preventive maintenance among the municipalities. Municipalities are required to improve the frequency and quality of pavement data collection, enhance the sophistication of PMS by using pavement deterioration models, and increase the maintenance budget and resources. An insight into the capabilities of municipalities would help in long-term strategic planning and effective utilisation of the maintenance budget to improve the street network across the country.
|
|
| 49. |
- Afridi, Muhammad Amjad, et al.
(författare)
-
Municipal street maintenance challenges and management practices in Sweden
- 2023
-
Ingår i: Frontiers in Built Environment. - : Frontiers Media S.A.. - 2297-3362. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- The municipal street network acts as a multifunctional asset by providing people, vehicles and public services with a well-functioning infrastructure. To keep it in good condition, optimal maintenance measures are required which would result in an efficient use of taxpayers' money. This paper investigates the street network deterioration processes and the management practices that the municipal administrations have applied in Sweden. The study is based on a survey with Swedish municipalities using questionnaires and complementary interviews. The answers provide insight into a wide range of common pavement distresses and deterioration factors, along with pavement management practices. The study identifies that potholes, surface unevenness and alligator cracking are the most cited challenges, while pavement ageing, heavy traffic and patches are the most noted causes. Similarly, the cold climate and population density are influential factors in pavement deterioration. Allocation of the maintenance and rehabilitation and reconstruction budget is higher in the northern part of the country as well as in densely populated municipalities. Condition data collection and use of commercial Pavement Management Systems (PMS) are limited. Addressing the challenges effectively may be possible through the enhancement of the budget, feasible/clear guidelines from municipal councils/politicians, and reducing the gap between street network administrations and utility service providers.
|
|
| 50. |
- Afridi, Muhammad Amjad, et al.
(författare)
-
Municipal Street Pavement Management Systems in Sweden
- 2024
-
Ingår i: Proceedings of the 10th International Conference on Maintenance and Rehabilitation of Pavements - MAIREPAV10 - Volume 2. - : Springer Nature. ; , s. 437-446, s. 437-446
-
Konferensbidrag (refereegranskat)abstract
- Street pavements are subject to various types of distress which necessitate a cost-effective management approach. This paper presents the outcomes of a survey focusing on street pavement maintenance and the utilization of machine learning (ML) pavement performance models on a 320 km municipal street network in Skellefteå municipality, Sweden. The findings reveal that the most common types of distress on Swedish streets include potholes, surface unevenness and alligator cracking, while prevalent causes of these distress are pavement ageing, heavy traffic and pavement patches. The windshield method of assessment of street pavement is prevalent, but the use of pavement management systems (PMS) is limited and pavement performance models are rarely employed. The case study reveals that Random Forest (RF) models developed for non-residential streets perform better than residential street models. RF models based on the variables age (A) and traffic (T) emerged as the best models, with 84% prediction accuracy. However, the R-squared value for the RF model applied to residential streets was 0.53, slightly surpassing the values for all models applied to non-residential streets (0.31, 0.50, 0.49). Further evaluation of models is suggested by using additional data.
|
|
