14 research outputs found

    Introduction to Communications in Transportation

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    69A3551747115/Project: 06-008As new Intelligent Transportation Systems (ITS) and vehicle-to-everything (V2X) communication technology and protocols continue to emerge, additional training is needed for personnel working in the transportation sector. The Virginia Department of Transportation has already created a training program focusing on general topics pertaining to connected and automated vehicles (CAVs) and has recently identified a need for a more specific program focusing on communication technologies. To address this need, the Virginia Tech Transportation Institute team developed a 60-minute online learning program that includes a series of 10 narrated modules with slides, images, charts, videos, and learning assessments. The training provides a high-level overview of the types of communications that support ITS, traffic management, and connected vehicle environments. The training includes descriptions of the communication technologies, protocols, performance metrics, use cases, and data security. The included communication technologies are currently being utilized by infrastructure owner-operators (IOOs), original equipment manufacturers (OEMs), and industry technology providers

    Signal Awareness Applications

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    69A3551747115/Project VTTI-00-021Intersection collisions account for 40% of all crashes on U.S. roadways. It is estimated that 165,000 accidents, which result in approximately 800 fatalities annually, are due to vehicles that pass through intersections during red signal phases. Although infrastructure-based red-light violation countermeasures have been deployed, intersections remain a top location for vehicle crashes. The Virginia Department of Transportation and its research arm, the Virginia Transportation Research Council, partnered with the Virginia Tech Transportation Institute to create the Virginia Connected Corridors (VCC), a connected vehicle test bed located in Fairfax and Blacksburg, Virginia, that enables the development and assessment of early-stage connected and automated vehicle applications. Recently, new systems have been deployed that transmit position correction messages to support lane-level accuracy, enabling development of signal awareness applications such as red-light violation warning. This project enhances the current capabilities of VCC platforms by developing new signal awareness safety and mobility features. Additionally, this project investigated the technical and human factors constraints associated with user interfaces for notifying and alerting drivers to pertinent intersection-related information to curb unsafe driving behaviors at signalized intersections

    Evaluation Tools for Low-Speed Automated Vehicle (LSAV) Transit Readiness of the Area

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    69A3551747115/Project 05-113Automated shuttles are small, low-speed (generally less than 25 mph) vehicles that do not require a human operator, though to date all have included an onboard human attendant. This project aims to assess the limitations that the EasyMile EZ10 Gen 3 low-speed automated vehicle (LSAV) encountered while operating on public roadways. The primary interests are to evaluate the infrastructure elements that posed the most challenges for the LSAV during its deployment. Further, the EasyMile EZ10 Gen 3 is advertised as being capable of operating at SAE International Level 4 Automated Driving System capability in certain ODDs. Accordingly, the team deployed the LSAV with the expectation that it would be operated at SAE Level 2 capability. The human safety operator was required to intervene in scenarios beyond the vehicle\u2019s automated functional capability. The results of this analysis indicated that the LSAV operated at a lower than expected speed, experienced a high frequency of disengagements, and had a regular need for safety operator intervention. These results suggest that the EZ10 Gen 3 vehicle is not yet operating at SAE International Level 4 capability on routes with moderate complexity

    A Critical Review of Approaches to the Design of Floating-Liner Apparatus for Instantaneous Piston Assembly Friction Measurement

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    Several approaches have been developed to measure instantaneous friction between the piston assembly and cylinder in internal combustion (IC) engines, such as floating-liner, reciprocating liner, instantaneous mean effective pressure (IMEP), fixed sleeve, and (P-ω) method and tribological bench tests. However, the “floating-liner method” and the “(IMEP) method” are the most common methods used to measure instantaneous friction between the piston assembly and IC engines. This paper critically evaluates different approaches to the design of the “floating-liner”. The paper begins by discussing piston assembly frictional losses and their significance and then discuss the development of instantaneous piston-friction measurements. After that, it reviews the main design challenges in the floating-liner approach. “Methods of cylinder sealing” and “force balancing methods” are also reviewed. Design challenges associated with firing operation were presented. Floating-liner designs were classified into different categories with a detailed presentation of the features of each. The paper ends by presenting a range of broad recommendations for further work which would benefit future designs

    Genome-wide association study of REM sleep behavior disorder identifies polygenic risk and brain expression effects

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    Rapid-eye movement (REM) sleep behavior disorder (RBD), enactment of dreams during REM sleep, is an early clinical symptom of alpha-synucleinopathies and defines a more severe subtype. The genetic background of RBD and its underlying mechanisms are not well understood. Here, we perform a genome-wide association study of RBD, identifying five RBD risk loci near SNCA, GBA, TMEM175, INPP5F, and SCARB2. Expression analyses highlight SNCA-AS1 and potentially SCARB2 differential expression in different brain regions in RBD, with SNCA-AS1 further supported by colocalization analyses. Polygenic risk score, pathway analysis, and genetic correlations provide further insights into RBD genetics, highlighting RBD as a unique alpha-synucleinopathy subpopulation that will allow future early intervention

    Defining the causes of sporadic Parkinson's disease in the global Parkinson's genetics program (GP2)

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    The Global Parkinson’s Genetics Program (GP2) will genotype over 150,000 participants from around the world, and integrate genetic and clinical data for use in large-scale analyses to dramatically expand our understanding of the genetic architecture of PD. This report details the workflow for cohort integration into the complex arm of GP2, and together with our outline of the monogenic hub in a companion paper, provides a generalizable blueprint for establishing large scale collaborative research consortia

    Multi-ancestry genome-wide association meta-analysis of Parkinson?s disease

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    Although over 90 independent risk variants have been identified for Parkinson’s disease using genome-wide association studies, most studies have been performed in just one population at a time. Here we performed a large-scale multi-ancestry meta-analysis of Parkinson’s disease with 49,049 cases, 18,785 proxy cases and 2,458,063 controls including individuals of European, East Asian, Latin American and African ancestry. In a meta-analysis, we identified 78 independent genome-wide significant loci, including 12 potentially novel loci (MTF2, PIK3CA, ADD1, SYBU, IRS2, USP8, PIGL, FASN, MYLK2, USP25, EP300 and PPP6R2) and fine-mapped 6 putative causal variants at 6 known PD loci. By combining our results with publicly available eQTL data, we identified 25 putative risk genes in these novel loci whose expression is associated with PD risk. This work lays the groundwork for future efforts aimed at identifying PD loci in non-European populations

    Infrastructure-Based Performance Evaluation for Low-Speed Automated Vehicle (LSAV)

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    This study assessed the limitations of the EasyMile EZ10 Gen 3 low-speed automated vehicle (LSAV) while operating on public roadways. The primary interest was to evaluate the infrastructure elements that posed the greatest challenges for the LSAV. A route was chosen that would satisfy a legitimate transit need. This route included more operational complexity and higher traffic volumes than a typical EasyMile LSAV deployment. The results indicate that the LSAV operated at a lower-than-expected speed (6 to 8 mph), with a high frequency of disengagements, and a regular need for safety operator intervention. Four-way stop-sign controlled intersections, three-lane roads with a shared turning lane in the middle, open areas, and areas without clear markings were the most challenging for the LSAV. Some important considerations include the need to have LSAVs operate on roadways where other vehicles may pass more safely, or on streets with slower posted speed limits. Additionally, the low passenger capacity and inability to understand where passengers are located onboard make it hard for the LSAV to replace bus transits. Currently, the LSAV is best suited to provide first/last-mile services, short routes within a controlled access area, and fill in gaps in conventional transits
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