bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of Software Tools to Implement a Systems Engineering Process for Specification Development in a Brownfield Train Control Project
Authors: Chy John , Diemunsch Kenneth , Banks Bradley 
Published: July 2019

When a signaling system reaches its end of life, an overall replacement is necessary. The replacement may be in-kind but for many mass transit agencies, it is common that capacity needs will have grown significantly, and the transit agency is required to increase capacity while tackling obsolescence. Capacity and obsolescence are the primary reasons for deploying Communications Based Train Control (CBTC) technology to replace conventional trip stop and track circuit-based systems operated by New York City Transit (NYCT) or cab signaling systems operated by Baltimore Maryland Transit Administration (MTA) and the San Francisco Bay Area Rapid Transit District (BART). Resignaling projects are often refereed as brownfield train control projects.
Due to the technical and commercial complexity, the quantity of stakeholders, the number of interfaces, the regulatory involvement via safety certification, the temporal and geographic scale of the project and the continual evolution of the existing system, a robust Systems Engineering (SE) process is necessary to achieve success in large signaling replacement projects.
This paper describes the software tools and processes that were deployed to meet the technical, legal and commercial needs of a large signaling replacement project during the specification development phase. The processes put in place were tailored to the size and location of the team members. The paper describes the software tools, such as IBM Rational DOORS, Microsoft SharePoint Online and Office 365 which were integrated and configured to allow for collaboration while accounting for the security, commercial and legal requirements of the agency. The selection, deployment and management of these processes and tools enabled the large, complex project to succeed.
Safety and Security Analysis for Movable Railroad Bridges
Authors: Wang Yongxin , Jablonski Matthew , Yavvari Chaitanya , Wang Zezhou , Liu Xiang , Holt Keith , Wijesekera Duminda 
Published: July 2019

Movable railroad bridges, consisting of lift, bascule, or swing bridges have been used by American rail tracks that cross usable waterways for over a century. Although custom made, movable bridges share many common components and designs. Most of them use weight bearing towers for the movable span using electric or electro-hydraulic systems lift and/or rotate these movable spans. Automated locks hold the bridge in place as soon as the movement stops. The bridge operation, train and ship signaling systems work in synchrony for trains and waterway traffic to be granted safe passage with minimal delay. This synchrony is maintained by using custom-made control systems using Programmable Logic Controllers (PLCs) or Field Programmable Gate Arrays (FPGAs). Controllers located on the movable and the static parts of the bridge communicate using radio and/or wired underwater links sometimes involving marine cables.
The primary objective of this paper is to develop a framework to analyze the safety and security of the bridge operating systems and their synchronous operations with railway and waterway systems. We do so by modeling the movable physical components and their control system with the interconnected network system and determine the faults and attacks that may affect their operations. Given the prevalence of attacks against PLCs, FPGAs and controllers, we show a generic way to determine the effect of what if scenarios that may arise due to attacks combined with failures using a case study of a swing bridge.
On Numerical Analyses of Rail Steel Fatigue Crack Growth Data
Authors: Jeong David Y. 
Published: July 2019

For a given material and set of test conditions, fatigue crack propagation behavior can be described by the relationship between cyclic crack-growth rate, da/dN and the fluctuation of stress intensity factor, △K. Such test data are usually displayed in a log-log plot. At intermediate values of △K, fatigue crack-growth data fall along a straight line such that a power-law equation may be used as a curve-fit to the data. Various numerical techniques are applied in order to (1) derive the crack-growth rate and (2) determine the parameters for the power-law equation.
Using data from laboratory tests conducted on rail steels, this paper explores the various numerical methods used to characterize fatigue crack-growth behavior. Tests were conducted using two different fracture-mechanics specimens (a standard compact tension specimen and a non-standard single edge notch specimen). Three different numerical techniques were applied to determine the fatigue crack-growth rate, da/dN from test data measuring crack length, a versus number of fatigue cycles, N: (1) secant method, (2) modified secant method, and (3) incremental polynomial method. Four different least squares regression analyses were then applied to determine the parameters for the power law. Moreover, the outcome of these analyses is to determine the combination of numerical techniques which yields the least amount of error when the crack-growth rate equation is integrated and compared to the original a versus N data. Fatigue life calculations performed by integrating the crack-growth rate equation demonstrate the sensitivity of predicted growth rates to the power-law parameters derived from the different regression analyses.
This paper explores the various numerical methods and techniques employed to analyze fatigue crack growth data using test data on rail steels.
Boundary Conditions Effects on the Crack Growth Mechanism Under Cycling Bending
Authors: Pucillo Giovanni Pio , Esposito Luca , Leonetti Davide 
Published: July 2019

The recent increase of train speed and frequency determines a rise of the loads transmitted to the superstructure. Therefore, railway components might experience service loads that have not considered at the design stage. Moreover, wear and backlash modification between components of a mechanical system might be able to modify the internal boundary conditions of the assembly. According to damage tolerance philosophy, an initial flaw is assumed to exist in the fatigue critical location of a structural component, and the analysis of the crack propagation life for such component needs accurate Stress Intensity Factor (SIF) evaluations.
In this study, the effects of the boundary conditions on the crack propagation life have been evaluated for a semi-elliptical surface crack having semi-axes a and c and growing from the root of a shoulder fillet notch in a round bar loaded in bending. Two cases have been analyzed: - the shoulder is free from external forces; - the shoulder is in contact with an adjacent generic body.
At first, the SIF distribution has been calculated with the Virtual Crack Closure Technique, considering or not the nonlinear effect induced by the contact forces arising from the interaction between the shoulder and the neighboring component. Successively, in both the above cases a two-parameters propagation law has been utilized to predict the evolution of both crack shape and crack depth when a cyclic bending load is applied to the rod. For this purpose, different values of the Stress Concentration Factor at the root of the fillet, and of the initial aspect ratio of the crack front, were considered in the calculations.
It is found that the aspect ratio evolves to a unique asymptote, taking or not into account the non-linearity introduced by the contact at the shoulder, and this value depends on the notch severity.
The ratio between the dimensionless SIFs obtained with and without the unilateral constraint at the shoulder, βcs / βfs, does not depend on the relative crack depth and crack shape. Also, the effect of the notch severity on the dimensionless SIF appears to be evident only for the portion of the crack front in the vicinity of the free surface.
Enhancements in the Performance of Journal Bearing Grease
Authors: Blasko Daniel S. , Aindow David , Mistry Kuldeep K. 
Published: July 2019

Wheelsets are removed from service for many reasons by North American Interchange Service. For example, journal bearings can be the cause of wheelset removal when operating temperature or acoustic signatures recorded by wayside detectors exceed certain limits. The Association of American Railroads (AAR) has established 13 failure progression modes to categorize the reason a bearing sets off one of these two detection systems. This study focuses on two failure progression modes: water etch caused by corrosion and issues associated with lubrication (grease).
Greases for rail journal bearings are expected to satisfy a wide variety of requirements such as moisture tolerance, mechanical stability, vibration tolerance, range of operating temperatures and oxidation resistance, to name a few. This paper provides the reader an overview of several experiments and tests that were conducted with the goal of extending service life and reducing corrosion, including field tests used in the development of advanced journal bearing greases for the rail industry. One such new grease formulation was tested in the UK with good results.
Implementation of a cloud-based referral platform in ophthalmology: making telemedicine services a reality in eye care
Authors: Kern Christoph , Fu Dun Jack , Kortuem Karsten , Huemer Josef , Barker David , Davis Alison , Balaskas Konstantinos , Keane Pearse A , McKinnon Tom , Sim Dawn A 
Published: July 2019

BackgroundHospital Eye Services (HES) in the UK face an increasing number of optometric referrals driven by progress in retinal imaging. The National Health Service (NHS) published a 10-year strategy (NHS Long-Term Plan) to transform services to meet this challenge. In this study, we implemented a cloud-based referral platform to improve communication between optometrists and ophthalmologists.MethodsRetrospective cohort study conducted at Moorfields Eye Hospital, Croydon (NHS Foundation Trust, London, UK). Patients classified into the HES referral pathway by contributing optometrists have been included into this study. Main outcome measures was the reduction of unnecessary referrals.ResultsAfter reviewing the patient’s data in a web-based interface 54 (52%) out of 103 attending patients initially classified into the referral pathway did not need a specialist referral. Fourteen (14%) patients needing urgent treatment were identified. Usability was measured in duration for data input and reviewing which was an average of 9.2 min (median: 5.4; IQR: 3.4–8.7) for optometrists and 3.0 min (median: 3.0; IQR: 1.7–3.9) min for ophthalmologists. A variety of diagnosis was covered by this tool with dry age-related macular degeneration (n=34) being most common.ConclusionAfter implementation more than half of the HES referrals have been avoided. This platform offers a digital-first solution that enables rapid-access eye care for patients in community optometrists, facilitates communication between healthcare providers and may serve as a foundation for implementation of artificial intelligence.
Clinical specialty training in UK undergraduate medical schools: a retrospective observational study
Authors: Vaidya Hrisheekesh J , Emery Alexander W , Alexander Emma C , McDonnell Angus J , Burford Charlotte , Bulsara Max K 
Published: July 2019

ObjectivesTo determine if increased exposure to clinical specialties at medical school is associated with increased interest in pursuing that specialty as a career after foundation training.DesignA retrospective observational study.Setting31 UK medical schools were asked how much time students spend in each of the clinical specialties. We excluded two schools that were solely Graduate Entry, and two schools were excluded for insufficient information.Main outcome measuresTime spent on clinical placement from UK undergraduate medical schools, and the training destinations of graduates from each school. A general linear model was used to analyse the relationship between the number of weeks spent in a specialty at medical school and the percentage of graduates from that medical school entering each of the Core Training (CT1)/Specialty Training (ST1) specialties directly after Foundation Year 2 (FY2).ResultsStudents spend a median of 85 weeks in clinical training. This includes a median of 28 weeks on medical firms, 15 weeks in surgical firms, and 8 weeks in general practice (GP). In general, the number of training posts available in a specialty was proportionate to the number of weeks spent in medical school, with some notable exceptions including GP. Importantly, we found that the number of weeks spent in a specialty at medical school did not predict the percentage of graduates of that school training in that specialty at CT1/ST1 level (ß coefficient=0.061, p=0.228).ConclusionsThis study found that there was no correlation between the percentage of FY2 doctors appointed directly to a CT1/ST1 specialty and the length of time that they would have spent in those specialties at medical school. This suggests that curriculum adjustments focusing solely on length of time spent in a specialty in medical school would be unlikely to solve recruitment gaps in individual specialties.
Optimising pacemaker therapy and medical therapy in pacemaker patients for heart failure: protocol for the OPT-PACE randomised controlled trial
Authors: Paton Maria F , Gierula John , Jamil Haqeel A , Lowry Judith E , Byrom Rowena , Gillott Richard G , Chumun Hemant , Cubbon Richard M , Cairns David A , Stocken Deborah D , Kearney Mark T , Witte Klaus K 
Published: July 2019

IntroductionPermanent artificial pacemaker implantation is a safe and effective treatment for bradycardia and is associated with extended longevity and improved quality of life. However, the most common long-term complication of standard pacemaker therapy is pacemaker-associated heart failure. Pacemaker follow-up is potentially an opportunity to screen for heart failure to assess and optimise patient devices and medical therapy.Methods and analysisThe study is a multicentre, phase-3 randomised trial. The 1200 participants will be people who have a permanent pacemaker for bradycardia for at least 12 months, randomly assigned to undergo a transthoracic echocardiogram with their pacemaker check, thereby tailoring their management directed by left ventricular function or the pacemaker check alone, continuing with routine follow-up. The primary outcome measure is time to all-cause mortality or heart failure hospitalisation. Secondary outcomes include external validation of our risk stratification model to predict onset of heart failure and quality of life assessment.Ethics and DisseminationThe trial design and protocol have received national ethical approval (12/YH/0487). The results of this randomised trial will be published in international peer-reviewed journals, communicated to healthcare professionals and patient involvement groups and highlighted using social media campaigns.Trial registration numberNCT01819662.
Observational study to understand interpreter service use in emergency medicine: why the key may lie outside of the initial provider assessment
Authors: Benda Natalie C , Fairbanks Rollin J , Higginbotham D Jeffrey , Lin Li , Bisantz Ann M 
Published: July 2019

ObjectiveTo characterise the use of interpreter services and other strategies used to communicate with limited English proficient (LEP) patients throughout their emergency department visit.MethodsWe performed a process tracing study observing LEP patients throughout their stay in the emergency department. A single observer completed 47 hours of observation of 103 communication episodes between staff and nine patients with LEP documenting the strategy used to communicate (eg, professional interpreter, family member, own language skills) and duration of conversations for each communicative encounter with hospital staff members. Data collection occurred in a single emergency department in the eastern USA between July 2017 and February 2018.ResultsThe most common strategy (per communicative encounter) was for the emergency department staff to communicate with the patient in English (observed in 29.1% of encounters). Total time spent in communicating was highest using telephone-based interpreters (32.9% of total time spent communicating) and in-person interpreters (29.2% of total time spent communicating). Communicative mechanism also varied by care task/phase of care with the most use of interpreter services or Spanish proficient staff (as primary communicator) occurring during triage (100%) and the initial provider assessment (100%) and the lowest interpreter service use during ongoing evaluation and treatment tasks (24.3%).ConclusionsEmergency department staff use various mechanisms to communicate with LEP patients throughout their length of stay. Utilisation of interpreter services was poorest during evaluation and treatment tasks, indicating that this area should be a focus for improving communication with LEP patients.
Inequalities in adolescent self-rated health and smoking in Europe: comparing different indicators of socioeconomic status
Authors: Moor Irene , Kuipers Mirte A G , Lorant Vincent , Pförtner Timo-Kolja , Kinnunen Jaana M , Rathmann Katharina , Perelman Julian , Alves Joana , Robert Pierre-Olivier , Rimpelä Arja , Kunst Anton E , Richter Matthias 
Published: July 2019

BackgroundAlthough there is evidence for socioeconomic inequalities in health and health behaviour in adolescents, different indicators of socioeconomic status (SES) have rarely been compared within one data sample. We examined associations of five SES indicators with self-rated health (SRH) and smoking (ie, a leading cause of health inequalities) in Europe.MethodsData of adolescents aged 14–17 years old were obtained from the 2013 SILNE survey (smoking inequalities: learning from natural experiments), carried out in 50 schools in 6 European cities (N=10 900). Capturing subjective perceptions of relative SES and objective measures of education and wealth, we measured adolescents’ own SES (academic performance, pocket money), parental SES (parental educational level) and family SES (Family Affluence Scale, subjective social status (SSS)). Logistic regression models with SRH and smoking as dependent variables included all SES indicators, age and gender.ResultsCorrelations between SES indicators were weak to moderate. Low academic performance (OR=1.96, 95% CI 1.53 to 2.51) and low SSS (OR=2.75, 95% CI 2.12 to 3.55) were the strongest indicators of poor SRH after adjusting for other SES-indicators. Results for SSS were consistent across countries, while associations with academic performance varied. Low academic performance (OR=5.71, 95% CI 4.63 to 7.06) and more pocket money (OR=0.21, 95% CI 0.18 to 0.26) were most strongly associated with smoking in all countries.ConclusionsSocioeconomic inequalities in adolescent health were largest according to SES indicators more closely related to the adolescent’s education as well as the adolescent’s perception of relative family SES, rather than objective indicators of parental education and material family affluence. For future studies on adolescent health inequalities, consideration of adolescent-related SES indicators was recommended.
Development and evaluation of a craniocerebral model with tactile-realistic feature and intracranial pressure for neurosurgical training
Authors: Yi Zongchao , He Bingwei , Liu Yuqing , Huang Shenyue , Hong Wenyao 
Published: July 2019

ObjectiveIn this article, a craniocerebral model is introduced for neurosurgical training, which is patient-specific, tactile-realistic, and with adjustable intracranial pressure.MethodsThe patient-specific feature is achieved by modeling from CT scans and magnetic resonance images (MRI). The brain tissue model is built by the hydrogel casting technique, while scalp, skull, vasculature, and lateral ventricles are all-in-one fabricated by three-dimensional (3D) printing. A closed-loop system is integrated to monitor and control the intracranial pressure. 3D measurements, mechanical tests, and simulated external ventricular drain (EVD) placement procedures are conducted on the model.ResultsA neurosurgical training model is completed with high accuracy (mean deviation 0.36 mm). The hydrogel brain tissue has a stiffness more similar to that of a real brain than the common 3D printed materials. The elasticity modulus of hydrogel brain tissue model is E=25.71 kPa, compared with our softest 3D printed material with E=1.14×103 kPa. Ten experienced surgeons rate the tactile realness of the neurosurgical training model at an average point of 4.25 on a scale from 1 (strongly negative) to 5 (strongly positive). The neurosurgical training model is also rated to be realistic in size (4.82), anatomy (4.70), and effective as an aid to improve blind EVD placement skills (4.65).ConclusionsThe neurosurgical training model can provide trainee surgeons with realistic experience in both tactile feedbacks and craniocerebral anatomy, improving their surgical skills.
Limitations of periodical health examinations in detecting occupational chronic solvent encephalopathy
Authors: Furu Heidi M , Sainio Markku , Hyvärinen Hanna-Kaisa , Kaukiainen Ari 
Published: July 2019

ObjectivesOccupational diseases (ODs) are globally underdetected, and chronic solvent encephalopathy (CSE) is no exception. The aim was to study how the recommended policies and protocols were followed in occupational health services (OHS) periodical health examinations where symptomatic CSE cases have remained undetected.MethodsWe retrospectively studied the medical records of occupational CSE cases (n=18) found in a screening project, which had not been detected in preceding OHS health examinations. We collected data from three sources: OHS units, the screening project and the Finnish Institute of Occupational Health. We analysed the health examinations conducted between symptom onset and the detection of CSE: regularity, content, use of recommended screening tools, exposure estimation and whether a physician was involved in the examinations, as recommended.ResultsThe mean duration of symptoms before OD identification was 7.3 years (range 3–13), and 36 health examinations had been conducted. Fifteen workers had attended these (1–9 times each) while suffering from CSE symptoms, and two before symptoms. Only one had not had access to OHS. The recommended symptom screening questionnaire, Euroquest, was used in five (14%) examinations, and previous solvent exposure inquired once. A physician was involved in 24 (67%) examinations, whereas the rest were carried out by a nurse.ConclusionsAlthough health examinations are conducted, guidelines are not followed. This may be due to a lack of awareness concerning CSE, and may apply to other ODs. In addition to legislation and policies, OH professionals must be continuously educated to improve awareness, prevention and detection of ODs.