scholarly journals Optimizing Road Networks for Automated Vehicles with Dedicated Links, Dedicated Lanes, and Mixed-Traffic Subnetworks

2021 ◽  
Vol 2021 ◽  
pp. 1-17
Author(s):  
Bahman Madadi ◽  
Rob Van Nes ◽  
Maaike Snelder ◽  
Bart Van Arem
Keyword(s):  
Large Scale ◽  
Transition Period ◽  
Road Networks ◽  
Network Design Problem ◽  
Metropolitan Region ◽  
Mathematical Framework ◽  
Mixed Traffic ◽  
Automated Vehicles ◽  
Network Topologies ◽  
Full Automation

This study focuses on network configurations to accommodate automated vehicles (AVs) on road networks during the transition period to full automation. The literature suggests that dedicated infrastructure for AVs and enhanced infrastructure for mixed traffic (i.e., AVs on the same lanes with conventional vehicles) are the main alternatives so far. We utilize both alternatives and propose a unified mathematical framework for optimizing road networks for AVs by simultaneous deployment of AV-ready subnetworks for mixed traffic, dedicated AV links, and dedicated AV lanes. We model the problem as a bilevel network design problem where the upper level represents road infrastructure adjustment decisions to deploy these concepts and the lower level includes a network equilibrium model representing the flows as a result of the travelers’ response to new network topologies. An efficient heuristic solution method is introduced to solve the formulated problem and find coherent network topologies. Applicability of the model on real road networks is demonstrated using a large-scale case study of the Amsterdam metropolitan region. Our results indicate that for low AV market penetration rates (MPRs), AV-ready subnetworks, which accommodate AVs in mixed traffic, are the most efficient configuration. However, after 30% MPR, dedicated AV lanes prove to be more beneficial. Additionally, road types can dictate the viable deployment plan for certain parts of road networks. These insights can be used to guide planners in developing their strategies regarding road network infrastructure during the transition period to full automation.

Integration of automated vehicles in mixed traffic: Evaluating changes in performance of following human-driven vehicles

2021 ◽  
Vol 152 ◽  
pp. 106006
Author(s):  
Iman Mahdinia ◽  
Amin Mohammadnazar ◽  
Ramin Arvin ◽  
Asad J. Khattak
Keyword(s):  
Mixed Traffic ◽  
Automated Vehicles

scholarly journals Controllable and decomposable multidirectional synchronizations

2021 ◽  
Author(s):  
Gábor Bergmann
Keyword(s):  
Systems Engineering ◽  
Large Scale ◽  
Mathematical Framework ◽  
Collaborative Systems ◽  
Consistency Constraints ◽  
Restoration Mechanism ◽  
Common Goals ◽  
Access Privileges ◽  
Novel Concept ◽  
Engineering Projects

AbstractStudying large-scale collaborative systems engineering projects across teams with differing intellectual property clearances, or healthcare solutions where sensitive patient data needs to be partially shared, or similar multi-user information systems over databases, all boils down to a common mathematical framework. Updateable views (lenses) and more generally bidirectional transformations are abstractions to study the challenge of exchanging information between participants with different read access privileges. The view provided to each participant must be different due to access control or other limitations, yet also consistent in a certain sense, to enable collaboration towards common goals. A collaboration system must apply bidirectional synchronization to ensure that after a participant modifies their view, the views of other participants are updated so that they are consistent again. While bidirectional transformations (synchronizations) have been extensively studied, there are new challenges that are unique to the multidirectional case. If complex consistency constraints have to be maintained, synchronizations that work fine in isolation may not compose well. We demonstrate and characterize a failure mode of the emergent behaviour, where a consistency restoration mechanism undoes the work of other participants. On the other end of the spectrum, we study the case where synchronizations work especially well together: we characterize very well-behaved multidirectional transformations, a non-trivial generalization from the bidirectional case. For the former challenge, we introduce a novel concept of controllability, while for the latter one, we propose a novel formal notion of faithful decomposition. Additionally, the paper proposes several novel properties of multidirectional transformations.

scholarly journals On the structural connectivity of large-scale models of brain networks at cellular level

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Giuseppe Giacopelli ◽  
Domenico Tegolo ◽  
Emiliano Spera ◽  
Michele Migliore
Keyword(s):  
Large Scale ◽  
Brain Networks ◽  
Structural Connectivity ◽  
Network Models ◽  
Brain Regions ◽  
Cellular Level ◽  
Scale Model ◽  
Mathematical Framework ◽  
Underlying Mechanisms ◽  
Experimental Findings

AbstractThe brain’s structural connectivity plays a fundamental role in determining how neuron networks generate, process, and transfer information within and between brain regions. The underlying mechanisms are extremely difficult to study experimentally and, in many cases, large-scale model networks are of great help. However, the implementation of these models relies on experimental findings that are often sparse and limited. Their predicting power ultimately depends on how closely a model’s connectivity represents the real system. Here we argue that the data-driven probabilistic rules, widely used to build neuronal network models, may not be appropriate to represent the dynamics of the corresponding biological system. To solve this problem, we propose to use a new mathematical framework able to use sparse and limited experimental data to quantitatively reproduce the structural connectivity of biological brain networks at cellular level.

scholarly journals A Parallel-Computing Approach for Vector Road-Network Matching Using GPU Architecture

2018 ◽  
Vol 7 (12) ◽  
pp. 472 ◽  
Author(s):  
Bo Wan ◽  
Lin Yang ◽  
Shunping Zhou ◽  
Run Wang ◽  
Dezhi Wang ◽  
...  
Keyword(s):  
Road Network ◽  
Large Scale ◽  
Graphics Processing Unit ◽  
Road Networks ◽  
Processing Unit ◽  
Data Partition ◽  
Matching Method ◽  
The Road ◽  
Central Processing ◽  
Relaxation Matching

The road-network matching method is an effective tool for map integration, fusion, and update. Due to the complexity of road networks in the real world, matching methods often contain a series of complicated processes to identify homonymous roads and deal with their intricate relationship. However, traditional road-network matching algorithms, which are mainly central processing unit (CPU)-based approaches, may have performance bottleneck problems when facing big data. We developed a particle-swarm optimization (PSO)-based parallel road-network matching method on graphics-processing unit (GPU). Based on the characteristics of the two main stages (similarity computation and matching-relationship identification), data-partition and task-partition strategies were utilized, respectively, to fully use GPU threads. Experiments were conducted on datasets with 14 different scales. Results indicate that the parallel PSO-based matching algorithm (PSOM) could correctly identify most matching relationships with an average accuracy of 84.44%, which was at the same level as the accuracy of a benchmark—the probability-relaxation-matching (PRM) method. The PSOM approach significantly reduced the road-network matching time in dealing with large amounts of data in comparison with the PRM method. This paper provides a common parallel algorithm framework for road-network matching algorithms and contributes to integration and update of large-scale road-networks.

TrustVehicle – Improved Trustworthiness and Weather-Independence of Conditionally Automated Vehicles in Mixed Traffic Scenarios

2018 ◽  
pp. 75-89 ◽  
Author(s):  
Pamela Innerwinkler ◽  
Ahu Ece Hartavi Karci ◽  
Mikko Tarkiainen ◽  
Micaela Troglia ◽  
Emrah Kinav ◽  
...  
Keyword(s):  
Mixed Traffic ◽  
Automated Vehicles

PART 1: Finance: Transport Strategy for Polish Cities

1997 ◽  
Vol 1576 (1) ◽  
pp. 1-9
Author(s):  
Slobodan Mitric
Keyword(s):  
Mass Transport ◽  
Low Income ◽  
Local Governments ◽  
Large Scale ◽  
Road Networks ◽  
Cost Recovery ◽  
Urban Transport ◽  
Transport Infrastructure ◽  
Rolling Stock ◽  
Urban Road

A recent study requested by a group of mayors representing the largest Polish cities is summarized. The study was to be used as input into local and national debates about future directions of urban transport development in the country. The wider context is that of a major political and economic reform, begun in the late 1980s, involving no less than a rapidpaced transition from socialism to capitalism, featuring large-scale downsizing of the public sector, privatization, and a redistribution of political and resource powers from the state to local governments. Among the downstream effects of these changes has been an increase in private car ownership and use and a reduction in the market share of urban mass transit modes from between 80 and 90 percent of nonwalk daily trips to 70 percent or less. For transit operators, now owned by local governments, this has meant an added financial pressure coming after a decade of underinvestment in infrastructure, rolling stock, and other equipment. Large numbers of unemployed, retired, or otherwise low-income travelers, another consequence of restructuring the economy, have made it difficult to improve cost recovery by increasing fares. Traffic growth has generated congestion, since the structure and size of urban road networks were predicated on low car use. An urban transport strategy is proposed to respond to these problems. Its main short-term objective is to have an affordable and socially and environmentally acceptable modal split. In the longer term, the objective is to use the demand response to a much-reformed price system as the principal guide to how infrastructure and services should evolve. The key features of the strategy are as follows: ( a) evolution toward market-supplied services by a mixed-ownership mass transport industry; ( b) treatment of urban road networks as public utilities, focusing on cost recovery through pricing; ( c) linkage of pricing policies for mass transport and individual transport modes, in line with second-best thinking, aiming to reduce and even eliminate subsidies for both modes; and ( d) reliance on internally generated revenue leveraged by long-term borrowing to finance sectoral investments. It is therefore a counterpoint to a strategy wherein mass transport is a state-owned monopoly, the use of urban roads is subsidized as is mass transport, infrastructure investment is the instrument of preference as opposed to pricing, and sectoral investments and operating subsidies are financed from tax-generated budgets.

scholarly journals Extreme Climate Events, Household Decision-Making and Transitions in the Immediate Aftermath of Hurricane Sandy

2017 ◽  
Vol 21 (4) ◽  
pp. 139-150 ◽  
Author(s):  
William Solecki ◽  
Robin Leichenko ◽  
David Eisenhauer
Keyword(s):  
New York ◽  
Storm Surge ◽  
Large Scale ◽  
Hurricane Sandy ◽  
Metropolitan Region ◽  
Scale Transformation ◽  
Household Decision ◽  
Surge Flooding ◽  
Term Response

AbstractIt is five years since Hurricane Sandy heavily damaged the New York- New Jersey Metropolitan region, and the fuller character of the long-term response can be better understood. The long-term response to Hurricane Sandy and the flooding risks it illustrated are set in myriad of individual and collective decisions taken during the time following the event. While the physical vulnerability of this region to storm surge flooding and climate change risks including sea level rise has been well-documented within the scholarly literature, Sandy’s impact placed decision-makingpost extreme events into the forefront of public and private discussions about the appropriate response. Some of the most fundamental choices were made by individual homeowners who houses were damaged and in some cases made uninhabitable following the storm. These individuals were forced to make decisions regarding where they would live and whether Sandy’s impact would result in their moving. In the disaster recovery and rebuilding context, these early household struggles about whether to leave or stay are often lost in the wider and longer narrative of recovery. To examine this early phase, this paper presents results of a research study that documented the ephemeral evidence of the initial phase of recovery in coastal communities that were heavily impacted by Hurricane Sandy’s storm surge and flooding. Hurricane Sandy and the immediate response to the storm created conditions for a potential large-scale transformation with respect to settlement of the coastal zone. In the paper, we examine and analyze survey and interview results of sixty-one residents and two dozen local stakeholders and practitioners to understand the stresses and transitions experienced by flooded households and the implications for the longer term resiliency of the communities in which they are located.

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