bluuebunny/crossref_metadata_2025_split huggingface dataset:
Light Weight Rigid OCS in Elevated Section of Delhi MRTS
Authors: Pande Om Hari , Tewari Ashok , Kumar Sanjeev 
Published: August 2020

Abstract
Delhi Metro is the first Metro in the world to provide 25 kV AC Rigid Overhead Conductor System (ROCS) in underground Tunnel. Most of the metros worldwide runs on 1500 V DC. The Elevated section of Delhi Metro is also provided with 25 kV AC Flexible OHE systems. The system is designed in accordance with EN-50119, 50122.
MRTS system plays an important role in functioning of the city transport. In the national capital of India, the Delhi Metro has become lifeline of Delhi since it’s inauguration in December 2002. Even occasional disruption of services, not only creates inconvenience & chaos between commuters but also invites severe criticism from public & media.
A number of failures in flexible OHE have caused disruption of metro services in the past few years. In elevated & at grade sections, DMRC is using conventional 25 kV AC flexible OHE where contact wire is suspended from a stranded messenger wire. Detailed analysis of the failure incidents indicated that catenaries’ parting and strands breakages due to short circuit contribute a significant portion i.e. 49% of total flexible OHE failures, While ROCS in underground stations is giving almost trouble-free services. Exploration of the possibilities of adopting Rigid OCS in elevated section shall help in reducing the breakdowns in 25kV traction as this will eliminate the component (i.e. Messenger wire) which is responsible for major failure. Also, mechanical properties of ROCS during electrical faults are far superior to that of flexible OHE.
The Next Generation of Train Control for Canadian Heavy Haul Systems
Authors: Thurston David F. 
Published: August 2020

Abstract
Heavy Haul Rail Transport in Canada has not advanced as in other countries. This gives these railways a chance to leap over intermediate technology in Train Control, Asset Management and levels of RAMS not offered in previous designs. Train Control is part of a System of Systems (SoS) that provides the basis of safety for operations, while allowing other non-vital systems to be implemented cheaper and faster than systems currently being modified to perform these tasks. This paper performs several tasks. First, it will update the reader on work being performed under the auspices of the Railway Association of Canada for Enhanced Train Control, and then it will describe how Train Control will interact with other systems to provide the overall functionality for safe train movement. Finally, the base requirements for a Train Control System meeting the requirements for Enhanced Train Control will be described.
The initial concepts and designs will be presented to show how the requirements will be met. In addition, the pilot project that is underway for proof of concept and operational readiness will be detailed. Test cases will be illustrated and portions of an Operational Concept, Requirements Analysis and Form Fit ad Function (F3) specifications will be documented. All of this will be the stepping stone for other systems to lead in advanced functionality and operation on Canadian Railways of the future.
Wireless Communication for High-Speed Passenger Rail Services: A Study on the Design and Evaluation of a Unified Architecture
Authors: Banerjee Subharthi , Hempel Michael , Ghasemzadeh Pejman , Sharif Hamid , Omar Tarek 
Published: August 2020

Abstract
High-speed trains, though prevalent in Europe and Asia, are not yet a reality in the US. But interest and industry engagement are growing, especially around commercial hubs close to commuter homes for alleviating commute times. With support from the Federal Railroad Administration in the United States, the authors are exploring the design requirements, challenges, and technology capabilities for wireless communication between passenger cars, on-board systems and with trackside infrastructure, all using next-generation radio access technologies. Key aspects of this work focus on interoperability, modularity of the architecture to facilitate a future-proof design, high-performance operations for passenger services and ultra-low latency capabilities for train control operations.
This paper presents the theoretical studies and computer simulations of the proposed network architectures, as well as the results of an LTE/5G field test framework using an OpenAir-Interface (OAI)-based software-defined radio (SDR) approach. Through various test scenarios the OAI LTE/5G implementation is first evaluated in a lab environment and through field tests. These tests provide ground-truth data that can be leveraged to refine the computer simulation model for evaluating large-scale environments with high fidelity and high accuracy. Of particular focus in this evaluation are performance aspects related to delay, handover, bit error rate, frequency offset and achievable uplink/downlink throughput.
Probabilistic Fatigue Crack Growth of Detail Fractures in Different Rail Steels
Authors: Jeong David Y. , Woelke Pawel 
Published: August 2020

Abstract
The most common rail defect encountered in continuously welded rail is known as the detail fracture. The U.S. Department of Transportation, Federal Railroad Administration has sponsored and managed research over the past several decades to understand the structural integrity of rail in general, and the fatigue crack growth behavior of detail fractures in particular. Control of rail integrity and defect growth is conducted via periodic rail tests (i.e. inspections) to ensure that rail defects do not become large enough to cause rail failure. Moreover, federal regulations have been codified to establish a maximum interval between rail inspections based on the results of government-sponsored research.
Over the past several decades, however, rail manufacturing has evolved and improved, particularly the head-hardening process to improve wear resistance. Propagation life of railroad rail was examined in previous research using fatigue crack growth data for non-head-hardened rail. Recently Thornton-Tomasetti conducted research, sponsored by FRA, to examine the fatigue crack growth behavior of modern rail steels (i.e. railroad rails with head-hardening). The initial results of the more recent research effort were reported in the 2019 Joint Rail Conference.
In this paper, fatigue crack growth rate data generated for head-hardened rail are used to examine the fatigue crack growth life of detail fractures under nominal revenue service conditions. Moreover, this paper applies a probabilistic approach to estimate rail life to account for the inherent variability or scatter typically observed in fatigue crack growth rate data. Regression methods are employed to derive the parameters for the Walker crack growth rate equation, which are subsequently treated as correlated, multivariate, and normally distributed random variables. Data from four different rail steels are used in the regression analyses, which are referred to as: Advanced Head Hardened (AHH), Head Hardened (HH), Standard Strength (SS), and Colorado Fuel and Iron (CF&I). Monte Carlo simulations of fatigue growth of detail fractures are carried out to estimate fatigue life distributions for each of the different rails. The results from these four rail steels are compared to those based on the previous research for non-head-hardened rails. Implications of these comparisons on determining rail testing intervals are discussed.
Behaviour of Metro Coach on Newly Built Track in Kolkata
Authors: Danawe Hrishikesh Gajanan , Singh Sudhir Kumar , Racherla Vikranth , R. Singh Sanjay , Prasad Arun 
Published: August 2020

Abstract
This paper presents the behaviour of a new metro coach on a newly built track in Kolkata, India. Oscillation trials were conducted using LVDT sensors at different locations to monitor primary and secondary springs compression. Multibody dynamics model is built with actual parameters of coach and track in SIMPACK. The behaviour of the vehicle for given track with elevation and curvature changes has been studied. Vehicle performance has been evaluated based on safety, running behaviour and track fatigue mentioned in UIC 518. Results of primary and secondary spring compressions obtained from field trials and multibody dynamics model have been compared. Coach lateral and vertical acceleration, bogie lateral acceleration, static load at rail wheel contact and derailment coefficient obtained from the multibody dynamics model are discussed. Obtained results were within permission values. Scope of this paper lies in studying the vehicle performance in connection to safety and running behaviour of newly introduced metro in Kolkata.
A Literature Review on Railroad Tank Car Thermal Protection Systems
Authors: Bian Zheyong , Carchi Nathalie , Liu Xiang 
Published: August 2020

Abstract
Railroad tank car transportation is the most efficient way to transport large amounts of hazardous material. More than 2 million tank-car loads of hazardous materials (hazmat) are transported annually by rail in the United States. Recently, the boom in the production of petroleum crude oil and natural gases from shale has dramatically increased the rail transport volume of flammable energy resources. However, accidents do occur, and the transportation of flammable hazardous material can result in disastrous consequences. The fire can heat up a tank car, rapidly increasing the inside pressure and causing the tank car to either rupture or explode. Railroad companies are developing or seeking advanced thermal protection systems to prevent tank car explosion or prolong the burst time to win a sufficient rescue time. It is of great importance to understand the existing thermal protection systems used in hazmat tank cars and to identify key priorities that the government and industry consider for improving tank car thermal protection performance, providing guidance for future thermal protection material development. Thus, this paper reviews the literature on the effects and analysis of different tank car thermal protection systems, identifying the effectiveness of different thermal protection components, properties of thermal protection materials, and testing methodologies.
Different combinations of insulators and jackets are tested in order to observe the effects of the fire on the tank car. The tank car is tested while carrying hazardous material like liquefied petroleum gas, propane, and ethylene oxide, etc. This investigation analyzes the differences of thermal protection systems in prolonging the life span of a tank car engulfed in flames.
A tank car can use either material like fiberglass, ceramic fiber blankets, perlite powder, or urethane foam to better insulate and thermally protect the tank car. An insulator is shown to prolong the life span of a tank car since bare tank cars tend to heat up rapidly when exposed to flames. The thermal protection system of a tank car is built of insulators, jackets, and supporting material for the insulator. The supporting material and jacket combination with the insulator also prevent the tank car from heating up rapidly.
There are two primary testing methods, pool fire, and torch fire. Each type of fire has different outcomes and limits in which the tank car can withstand. When testing the heating of a tank car, thermocouples were placed throughout a tank car and recorded to check what areas were heated the most during the experiment. Some factors that had been accounted for in the previous studies were the wind speed and the direction of the wind, which affected the overall experiment, mostly torch fire experiments.
Field Testing Plan for Positive Train Control Enforcement in Passenger Terminals
Authors: Zhang Zhipeng , Liu Xiang , Holt Keith 
Published: August 2020

Abstract
In the United States, a train moving onto a terminating track at a passenger terminal relies on the train engineer’s operation. Currently, there are no mechanisms installed at the U.S. passenger terminals that are able to automatically stop a train before reaching the end of the track if an engineer fails to do so. The engineer’s actions determine whether the train will safely stop before the end of the terminating track. Thus, incapacitated or inattentive engineer operation would result in end-of-track collisions, such as the New Jersey Transit train accident at Hoboken Terminal in 2016. Currently, PTC enforcement is not required in passenger terminals. In an ongoing project tasked by the Federal Railroad Administration, we study the cost-effectiveness and operational impact of possible PTC enforcement to prevent end-of-track collisions. Specifically, a Concept of Operations (ConOps) was developed to outline the proposed plans to implement two of the most widely used PTC types, namely the Advanced Civil Speed Enforcement System (ACSES) and Interoperable Electronic Train Management System (I-ETMS). This paper describes in-field testing of the ConOps in ACSES-type terminal.
In the planned field test, a train equipped with one locomotive and at least one passenger coach would be tested on platform tracks in a selected passenger terminal. These are three major testing components, which are test equipment, test track, and recorded information for each test sequence. Firstly, in terms of equipment, a traffic cone will be placed on the track to simulate a bumping post. In ACSES system, two sets of transponders are programmed to require a positive stop within a specified distance and mounted to the cross ties at specified positions. Secondly, a yard track will be used to test the feasibility of this exercise at the beginning. Upon successfully completing the test multiple times, a series of tests will also be made on the studied platform track. Thirdly, each test run should record the distance from the head end of the test train and the traffic cone for each test run. In addition, ACSES system should also record the information on the ACSES display as it passes the first and second transponder set, respectively. Overall, the field tests presented in this paper, along with previous work in benefit-cost analysis and operational impact assessment, can contribute to an assessment of the proposed PTC implementation at stub-end terminals in the United States in order to effectively and efficiently prevent end-of-track collisions.
Characterize Rail Crack Pattern Through Image Analysis
Authors: DeVine Ryan , Qian Yu , Wang Yi , Wang Shaofeng , Rizos Dimitris 
Published: August 2020

Abstract
Railway provides more than 40% of the freight ton-miles moved in the U.S. each year, surpassing all other modes of transportation. In addition to moving more tonnage farther than other modes, trains have better fuel efficiency than trucks and airplanes due to the low friction between the wheels and the rails. With traffic accumulation, rails will degrade which may lead to different types of defects, including but not limited to spalling, separation, crack, and corrugation. Rail head fissures or surface crack is often associated with rolling fatigue and must be addressed through grinding or other maintenance activities to restore the smooth-running surface. This ensures the riding conforms to operational safety requirements. The growth pattern of rail surface cracks has not been thoroughly understood or well-quantified yet due to the difficulties of rail crack inspection and insufficient data. This paper presents a study that uses image analysis techniques to detect and quantify cracks in images of rail segments that were taken in the field. Various crack detection techniques were tested and compared with visual inspection, including thresholding, edge detection, and bottom-hat filtering. The crack length, direction, and curvature were also quantified with each approach. Cracks were found to grow not perpendicular to the rail head, but with a certain angle from the vertical direction and relatively evenly distributed along the rail. The bottom-hat filtering technique was found to be the best in terms of accuracy among the methods tested in this study. The results from the study fill the gap of the literature by quantitatively characterizing the rail crack growth pattern and helping to identify possible approaches for future autonomous crack detection.
Radiation Transport Simulation Results Assessment Through Comparison With Reduced Complexity Analytic and Computational Models (LA-UR-20-22342)
Authors: Remedes Tyler J. , Ramsey Scott D. , Schmidt Joseph H. , Baciak James 
Published: August 2020

Abstract
In the past when faced with solving a non-tractable problem, scientists would make tremendous efforts to simplify these problems while preserving fundamental physics. Solutions to the simplified models provided insight into the original problem. Today, however, the affordability of high-performance computing has inverted the process for analyzing complex problems. In this paradigm, results from detailed computational scenarios can be better assessed by “building down” the complex model through simple models rooted in the fundamental or essential phenomenology.
This work demonstrates how the analysis of the neutron flux spatial distribution behavior within a simulated Holtec International HI-STORM 100 spent fuel cask is enhanced through reduced complexity analytic and computational modeling. This process involves identifying features in the neutron flux spatial distribution and determining the cause of each using reduced complexity computational and/or analytic model. Ultimately, confidence in the accuracy of the original simulation result is gained through this analysis process.
Diagnosis of occupational asthma from serial measurements of forced expiratory volume in 1 s (FEV1) using the Area Between Curves (ABC) score from the Oasys plotter
Authors: Parkes Edward D , Moore Vicky C , Walters Gareth I , Burge Peter Sherwood 
Published: August 2020

ObjectivesTo identify the changes in serial 2-hourly forced expiratory volume in 1 s (FEV1) measurements required to identify occupational asthma (OA) using the Oasys Area Between Curves (ABC) score.MethodsThe ABC score from 2-hourly measurements of FEV1was compared between workers with confirmed OA and asthmatics without occupational exposure to identify the optimum separation using receiver operator characteristic (ROC) analysis. Separate analyses were made for plots using clock time and time from waking to allow for use in shift workers. Minimum record criteria were ≥6 readings per day, >4 day shifts and >4 rest days (or >9 days for controls).ResultsA retrospective analysis identified 22 workers with OA and 30 control asthmatics whose records reached the quality standards. Median FEV1diurnal variation was 20.3% (IQR 16.1–32.6) for OA and 19.5% (IQR 14.5–26.1) for asthmatic controls. ROC curve analysis identified that a difference of 0.056 L/hour gave a ROC score of 0.821 for clock time and 0.768 for time from waking with a sensitivity of 73% and a specificity of 93% for the diagnosis of OA.ConclusionsThe diagnosis of OA requires objective confirmation. Unsupervised serial FEV1measurements are more difficult to obtain reliably than measurements of peak expiratory flow, which are likely to remain the standard for general use. A FEV1ABC score >0.056 L/hour provides a valid cut-off for those who wish to use FEV1rather than peak expiratory flow.
Epidemiology of SARS-CoV-2 antibodies among firefighters/paramedics of a US fire department: a cross-sectional study
Authors: Caban-Martinez Alberto J , Schaefer-Solle Natasha , Santiago Katerina , Louzado-Feliciano Paola , Brotons Angel , Gonzalez Marco , Issenberg S. Barry , Kobetz Erin 
Published: August 2020

ObjectivesWe estimate the point seroprevalence of SARS-CoV-2 antibodies in the frontline firefighter/paramedic workforce of a South Florida fire department located in the epicentre of a State outbreak.MethodsA cross-sectional study design was used to estimate the point seroprevalence of SARS-CoV-2 antibodies using a rapid immunoglobulin (Ig)M-IgG combined point-of-care lateral flow immunoassay among frontline firefighters/paramedics collected over a 2-day period, 16–17 April 2020. Fire department personnel were emailed a survey link assessing COVID-19 symptoms and work exposures the day prior to the scheduled drive-through antibody testing at a designated fire station. Off-duty and on-duty firefighter/paramedic personnel drove through the fire station/training facility in their personal vehicles or on-duty engine/rescue trucks for SARS-CoV-2 antibody testing.ResultsAmong the 203 firefighters/paramedics that make up the fire department workforce, 18 firefighters/paramedics (8.9%) tested positive for SARS-CoV-2 antibodies, of which 8 firefighters/paramedics (3.9%) were IgG positive only, 8 (3.9%) were IgM positive only and 2 (0.1%) were IgG/IgM positive. The positive predictive value (PPV) of the serological test is estimated to be 33.2% and the negative predictive value is 99.3%. The average number of COVID-19 case contacts (ie, within 6 feet of an infected person (laboratory-confirmed or probable COVID-19 patient) for ≥15 min) experienced by firefighters/paramedics was higher for those with positive serology compared with those with negative (13.3 cases vs 7.31 cases; p=0.022). None of the antibody positive firefighters/paramedics reported receipt of the annual influenza vaccine compared with firefighters/paramedics who tested negative for SARS-CoV-2 antibodies (0.0% vs 21.0%; p=0.027).ConclusionRapid SARS-CoV-2 IgM-IgG antibody testing documented early-stage and late-stage infection in a firefighter workforce providing insight to a broader medical surveillance project on return to work for firefighters/paramedics. Given the relatively low PPV of the serological test used in this study back in April 2020, caution should be used in interpreting test results.
Differences in Transforming Growth Factor‐β1/BMP7 Signaling and Venous Fibrosis Contribute to Female Sex Differences in Arteriovenous Fistulas
Authors: Cai Chuanqi , Kilari Sreenivasulu , Singh Avishek K. , Zhao Chenglei , Simeon Michael L. , Misra Avanish , Li Yiqing , Misra Sanjay 
Published: August 2020

Background
Women have decreased hemodialysis arteriovenous fistula (AVF) maturation and patency rates. We determined the mechanisms responsible for the sex‐specific differences in AVF maturation and stenosis formation by performing whole transcriptome RNA sequencing with differential gene expression and pathway analysis, histopathological changes, and in vitro cell culture experiments from male and female smooth muscle cells.

Methods and Results

Mice with chronic kidney disease and AVF were used. Outflow veins were evaluated for gene expression, histomorphometric analysis, Doppler ultrasound, immunohistologic analysis, and fibrosis. Primary vascular smooth muscle cells were collected from female and male aorta vessels. In female AVFs, RNA sequencing with real‐time polymerase chain reaction analysis demonstrated a significant decrease in the average gene expression of
BMP7
(bone morphogenetic protein 7) and downstream
IL17Rb (interleukin 17 receptor b)
, with increased transforming growth factor‐β1 (
Tgf‐β1)
and transforming growth factor‐β receptor 1 (
Tgfβ‐r1)
. There was decreased peak velocity, negative vascular remodeling with higher venous fibrosis and an increase in synthetic vascular smooth muscle cell phenotype, decrease in proliferation, and increase in apoptosis in female outflow veins at day 28. In vitro primary vascular smooth muscle cell experiments performed under hypoxic conditions demonstrated, in female compared with male cells, that there was increased gene expression of
Tgf‐β1
,
Tgfβ‐r1
,
and
Col1
with increased migration.

Conclusions

In female AVFs, there is decreased gene expression of
BMP7
and
IL17Rb
with increased
Tgf‐β1
and
Tgfβ‐r1
, and the cellular and vascular differences result in venous fibrosis with negative vascular remodeling.