Development of an Integrated Model for the Evaluation and Planning of Railroad Track Maintenance

2013 ◽  
Author(s):  
Alexander H. Lovett ◽  
C. Tyler Dick ◽  
Conrad Ruppert ◽  
M. Rapik Saat ◽  
Christopher Barkan
Keyword(s):  
Indirect Costs ◽  
Cost Effective ◽  
Rolling Stock ◽  
Costs And Benefits ◽  
Track Maintenance ◽  
Wide Range ◽  
Maintenance Work ◽  
Service Disruption ◽  
Model Components ◽  
Acute Failure

In order for a railroad to function effectively all aspects of the system should be maintained in good working order. Locomotives and rolling stock regularly move through areas where they can be inspected and maintained. However track does not move, so inspectors must traverse the line either on foot or in a rail mounted vehicle and maintenance crews must be sent to specific locations to make track repairs, which may not always happen before a service disruption. A track failure, due to either exceeding some industry or governmental specification or an acute failure, such as a rail break, can result in costly delays or even derailments with significant consequences. To help avoid such failures, it is beneficial for a railroad to be able to predict when and where failures might occur and then evaluate the relative costs and benefits of performing maintenance activities to ensure that the most cost effective actions are taken. A model is being developed to assist in the process of scheduling and directing track maintenance work. The model consists of three primary modules: an integrated track quality and degradation module, a maintenance activity selection module, and a scheduling optimization module. By taking into account a wide range of costs and benefits, the model can help railroad infrastructure managers better account for risk and indirect costs such as track time, as well as account for the criticality of certain types of imminent failures. This paper will describe the inputs and outputs for the model, as well as detailing the concepts associated with each of the model components.

scholarly journals Optimization of work performance of snow removal work trains on the basis of linear programming

2018 ◽  
Vol 239 ◽  
pp. 04001 ◽  
Author(s):  
Aleksey Manakov ◽  
Andrey Abramov ◽  
Andrey Ilinykh ◽  
Vladimir Aksenov
Keyword(s):  
Linear Programming ◽  
Work Performance ◽  
Railway Track ◽  
Rolling Stock ◽  
Snow Removal ◽  
Track Maintenance ◽  
Maintenance Work ◽  
Optimization Methodology ◽  
The Cost ◽  
Removal Equipment

The introduction of monitoring systems for the work performance of special rolling stock and monitoring the load of snow removal work trains revealed a number of shortcomings in the planning, organization, and recording of work performed by snow removal work trains. The elimination of the identified problems is possible on the basis of optimization of work performance, the implementation of which can be achieved on the basis of existing systems with appropriate additional functionality. For this purpose, in the framework of the theoretical studies presented in the paper, a methodology for optimization of work performance of snow removal work trains has been developed. Linear programming is adopted as a method of solving the optimization problem. On the basis of the algorithm for solving the transport problem, the problem of minimizing the cost of snow removal from various sections of the track by the existing park of work trains is formulated, for which a mathematical model is constructed that includes the objective function and the corresponding restrictions. The results of the study show that the widespread use of work planning on the basis of the presented optimization methodology will make it possible to make the most efficient use of snow removal equipment and, as a result, to reduce the cost of this type of railway track maintenance work.

scholarly journals Importance and Applications of Robotic and Autonomous Systems (RAS) in Railway Maintenance Sector: A Review

Computers ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 56 ◽  
Author(s):  
Randika K. W. Vithanage ◽  
Colin S. Harrison ◽  
Anjali K. M. DeSilva
Keyword(s):  
Dominant Role ◽  
Autonomous Systems ◽  
Cost Effective ◽  
Rapid Expansion ◽  
Railway Track ◽  
Rolling Stock ◽  
Track Maintenance ◽  
Railway Industry ◽  
Railway Maintenance ◽  
Effective Service

Maintenance, which is critical for safe, reliable, quality, and cost-effective service, plays a dominant role in the railway industry. Therefore, this paper examines the importance and applications of Robotic and Autonomous Systems (RAS) in railway maintenance. More than 70 research publications, which are either in practice or under investigation describing RAS developments in the railway maintenance, are analysed. It has been found that the majority of RAS developed are for rolling-stock maintenance, followed by railway track maintenance. Further, it has been found that there is growing interest and demand for robotics and autonomous systems in the railway maintenance sector, which is largely due to the increased competition, rapid expansion and ever-increasing expenses.

scholarly journals The complex phenomenological model for prediction of inhomogeneous deformations of railway ballast layer after tamping works

2018 ◽  
Vol 47 (3) ◽  
pp. 91-107 ◽  
Author(s):  
Mykola Sysyn ◽  
Ulf Gerber ◽  
Vitalii Kovalchuk ◽  
Olga Nabochenko
Keyword(s):  
Experimental Studies ◽  
Rolling Stock ◽  
Key Factors ◽  
Railway Ballast ◽  
Track Geometry ◽  
Track Maintenance ◽  
Geometric Deviations ◽  
Maintenance Work ◽  
Residual Deformations ◽  
The Given

The given article considers the method of calculating the track geometry deformation with respect to uneven accumulation of residual deformations along the track. The technique proposes two significant changes in existing approaches to calculating the efficiency of the ballast layer. The transition from the approach of allowable stresses design in the ballast layer to the deformative approach of accumulations of track geometry deformations allows us to draw conclusions regarding the intervals of track tamping and the duration of ballast layer life cycle. The transition from the determinative to probabilistic approaches makes it possible to draw conclusions not only from the average unevenness, but also with regard to all possible facts of unevenness. The method is based on the mechanism of sudden and gradual deformations occurrence, which depends on a number of key factors: dynamic stresses on the ballast, non-uniformity of track elasticity, performance of current maintenance work. Based on the experimental studies results, the dependencies of sudden deformations and the intensity of gradual deformations on the level of stress on the ballast layer were established. The experimental results of the influence of the sub-ballast base elasticity on the intensity of accumulation of residual deformations are shown. On the basis of the developed method, the prediction of track geometry deterioration for a given structure of the track, the rolling stock and the permissible level of geometric deviations for track maintenance is presented.

2D Color-Intensity Representation of Ultrasonic Thickness Gauge Measurements

2020 ◽  
pp. 1192-1198
Author(s):  
M.S. Mohammad ◽  
Tibebe Tesfaye ◽  
Kim Ki-Seong
Keyword(s):  
Cost Effective ◽  
The Other ◽  
Thickness Gauge ◽  
Color Intensity ◽  
Digital Readout ◽  
Flat Surfaces ◽  
Video Cameras ◽  
Wide Range ◽  
Cost Effective Alternative ◽  
Ultrasonic Thickness

Ultrasonic thickness gauges are easy to operate and reliable, and can be used to measure a wide range of thicknesses and inspect all engineering materials. Supplementing the simple ultrasonic thickness gauges that present results in either a digital readout or as an A-scan with systems that enable correlating the measured values to their positions on the inspected surface to produce a two-dimensional (2D) thickness representation can extend their benefits and provide a cost-effective alternative to expensive advanced C-scan machines. In previous work, the authors introduced a system for the positioning and mapping of the values measured by the ultrasonic thickness gauges and flaw detectors (Tesfaye et al. 2019). The system is an alternative to the systems that use mechanical scanners, encoders, and sophisticated UT machines. It used a camera to record the probe’s movement and a projected laser grid obtained by a laser pattern generator to locate the probe on the inspected surface. In this paper, a novel system is proposed to be applied to flat surfaces, in addition to overcoming the other limitations posed due to the use of the laser projection. The proposed system uses two video cameras, one to monitor the probe’s movement on the inspected surface and the other to capture the corresponding digital readout of the thickness gauge. The acquired images of the probe’s position and thickness gauge readout are processed to plot the measured data in a 2D color-coded map. The system is meant to be simpler and more effective than the previous development.

The Future of Plasma-Based Surface Engineering Techniques in Tribology (Keynote)

2005 ◽  
Author(s):  
Allan Matthews ◽  
Adrian Leyland
Keyword(s):  
Surface Engineering ◽  
Performance Enhancement ◽  
Bulk Material ◽  
Cost Savings ◽  
Cost Effective ◽  
Ceramic Coatings ◽  
Performance Improvements ◽  
Treatment Techniques ◽  
Wide Range ◽  
Macro Scale

Over the past twenty years or so, there have been major steps forward both in the understanding of tribological mechanisms and in the development of new coating and treatment techniques to better “engineer” surfaces to achieve reductions in wear and friction. Particularly in the coatings tribology field, improved techniques and theories which enable us to study and understand the mechanisms occurring at the “nano”, “micro” and “macro” scale have allowed considerable progress to be made in (for example) understanding contact mechanisms and the influence of “third bodies” [1–5]. Over the same period, we have seen the emergence of the discipline which we now call “Surface Engineering”, by which, ideally, a bulk material (the ‘substrate’) and a coating are combined in a way that provides a cost-effective performance enhancement of which neither would be capable without the presence of the other. It is probably fair to say that the emergence and recognition of Surface Engineering as a field in its own right has been driven largely by the availability of “plasma”-based coating and treatment processes, which can provide surface properties which were previously unachievable. In particular, plasma-assisted (PA) physical vapour deposition (PVD) techniques, allowing wear-resistant ceramic thin films such as titanium nitride (TiN) to be deposited on a wide range of industrial tooling, gave a step-change in industrial productivity and manufactured product quality, and caught the attention of engineers due to the remarkable cost savings and performance improvements obtained. Subsequently, so-called 2nd- and 3rd-generation ceramic coatings (with multilayered or nanocomposite structures) have recently been developed [6–9], to further extend tool performance — the objective typically being to increase coating hardness further, or extend hardness capabilities to higher temperatures.

scholarly journals Gamma models for estimating the odds ratio for a skewed biomarker measured in pools and subject to errors

Biostatistics ◽  
2019 ◽  
Author(s):  
Dane R Van Domelen ◽  
Emily M Mitchell ◽  
Neil J Perkins ◽  
Enrique F Schisterman ◽  
Amita K Manatunga ◽  
...  
Keyword(s):  
Odds Ratio ◽  
Adjusted Odds Ratio ◽  
Lower Cost ◽  
Cost Effective ◽  
Ratio Estimation ◽  
Statistical Efficiency ◽  
Function Model ◽  
Processing Error ◽  
Wide Range ◽  
Pooled Samples

SUMMARYMeasuring a biomarker in pooled samples from multiple cases or controls can lead to cost-effective estimation of a covariate-adjusted odds ratio, particularly for expensive assays. But pooled measurements may be affected by assay-related measurement error (ME) and/or pooling-related processing error (PE), which can induce bias if ignored. Building on recently developed methods for a normal biomarker subject to additive errors, we present two related estimators for a right-skewed biomarker subject to multiplicative errors: one based on logistic regression and the other based on a Gamma discriminant function model. Applied to a reproductive health dataset with a right-skewed cytokine measured in pools of size 1 and 2, both methods suggest no association with spontaneous abortion. The fitted models indicate little ME but fairly severe PE, the latter of which is much too large to ignore. Simulations mimicking these data with a non-unity odds ratio confirm validity of the estimators and illustrate how PE can detract from pooling-related gains in statistical efficiency. These methods address a key issue associated with the homogeneous pools study design and should facilitate valid odds ratio estimation at a lower cost in a wide range of scenarios.

scholarly journals Sporulation in solventogenic and acetogenic clostridia

2021 ◽  
Author(s):  
Mamou Diallo ◽  
Servé W. M. Kengen ◽  
Ana M. López-Contreras
Keyword(s):  
Current Knowledge ◽  
Carbon Sources ◽  
Cost Effective ◽  
Biotechnological Production ◽  
Key Points ◽  
Wide Range ◽  
Potential Applications ◽  
A Cell ◽  
Sporulation Initiation ◽  
Solventogenic Clostridia

AbstractThe Clostridium genus harbors compelling organisms for biotechnological production processes; while acetogenic clostridia can fix C1-compounds to produce acetate and ethanol, solventogenic clostridia can utilize a wide range of carbon sources to produce commercially valuable carboxylic acids, alcohols, and ketones by fermentation. Despite their potential, the conversion by these bacteria of carbohydrates or C1 compounds to alcohols is not cost-effective enough to result in economically viable processes. Engineering solventogenic clostridia by impairing sporulation is one of the investigated approaches to improve solvent productivity. Sporulation is a cell differentiation process triggered in bacteria in response to exposure to environmental stressors. The generated spores are metabolically inactive but resistant to harsh conditions (UV, chemicals, heat, oxygen). In Firmicutes, sporulation has been mainly studied in bacilli and pathogenic clostridia, and our knowledge of sporulation in solvent-producing or acetogenic clostridia is limited. Still, sporulation is an integral part of the cellular physiology of clostridia; thus, understanding the regulation of sporulation and its connection to solvent production may give clues to improve the performance of solventogenic clostridia. This review aims to provide an overview of the triggers, characteristics, and regulatory mechanism of sporulation in solventogenic clostridia. Those are further compared to the current knowledge on sporulation in the industrially relevant acetogenic clostridia. Finally, the potential applications of spores for process improvement are discussed.Key Points• The regulatory network governing sporulation initiation varies in solventogenic clostridia.• Media composition and cell density are the main triggers of sporulation.• Spores can be used to improve the fermentation process.

scholarly journals A review on design and testing methodologies of modern freight train draft gear system

2021 ◽  
Author(s):  
Simon Wagner ◽  
Colin Cole ◽  
Maksym Spiryagin
Keyword(s):  
Soviet Union ◽  
South America ◽  
Former Soviet Union ◽  
Rolling Stock ◽  
Freight Train ◽  
Wide Range ◽  
Draft Gear ◽  
Design And Testing ◽  
Damping Systems ◽  
The Eu

AbstractRolling stock connection systems are key to running longer and heavier trains as they provide both the connections of vehicles and the damping, providing the longitudinal suspension of the train. This paper focuses on the evolution of both connection and stiffness damping systems. Focus is on freight rolling stock, but passenger draw gears are also examined. It was found that connection systems have evolved from the buff and chain system used in the pioneer railways of the 1800s to the modern auto-coupler connection systems that are in-service worldwide today. Refined versions of the buff and chain coupling are, however, still in use in the EU, UK, South America and India. A wide range of auto-coupler systems are currently utilised, but the AAR coupler (Janney coupler) remains the most popular. A further variation that persists is the SA3 coupler (improved Wilson coupler) which is an alternative auto-coupler design used mainly throughout the former Soviet Union. Restricting the review to auto-coupler systems allowed the paper to focus on draft gears which revealed polymer, polymer-friction, steel spring-friction, hydraulic draft gears and sliding sill cushioning systems. Along with the single compressive draft gear units balanced and floating plate configurations are also presented. Typical draft gear acceptance standards are presented along with modelling that was included to aid in presentation of the functional characteristics of draft gears.

scholarly journals Cost-of-illness for non-underweight binge-eating disorders

2021 ◽  
Author(s):  
Paul E. Jenkins
Keyword(s):  
Eating Disorders ◽  
Binge Eating ◽  
Economic Impact ◽  
Indirect Costs ◽  
Cost Effective ◽  
Level Of Evidence ◽  
Academic Impairment ◽  
The United Kingdom ◽  
Binge Eating Disorders ◽  
Low Weight

Abstract Purpose This study examined economic costs associated with untreated eating disorders (EDs) characterised by regular binge eating in the absence of low weight. Both direct and indirect costs were assessed, reporting a limited societal perspective of economic impact as some costs were not included. Methods One hundred and twenty six adults seeking treatment for recurrent binge eating were asked to report impairment associated with an ED. Costs were calculated using 2017 prices, including an examination of variables associated with costs. Results Estimated societal costs for the year preceding assessment were £3268.47 (€3758.54) per person. In multivariate analyses, no reliable baseline associates of cost were identified. Conclusion The economic burden of EDs characterised by regular binge eating is significant, and underscores the need for efficacious and cost-effective treatments. Individuals with binge-eating disorders report work impairment and healthcare use that may cost the United Kingdom economy upwards of £3.5 billion (€4bn) per annum. Further studies should consider academic impairment and the economic impact of EDs on families. Level of evidence III: evidence obtained from well-designed cohort or case–control analytic studies.

Narrowing longitudinally coupled prefabricated slab track maintenance duration with field data analysis of slab deformation under high temperature

2021 ◽  
pp. 095440972098626
Author(s):  
Zai-Wei Li ◽  
Xiao-Zhou Liu ◽  
Hong-Yao Lu ◽  
Yue-Lei He
Keyword(s):  
High Temperature ◽  
High Speed ◽  
Ride Comfort ◽  
Cost Effective ◽  
Periodic Variation ◽  
Longitudinal Force ◽  
Distribution Analysis ◽  
High Speed Rail ◽  
Track Maintenance ◽  
Slab Track

The deformation of longitudinally coupled prefabricated slab track (LCPST) due to high temperature may lead to a reduction in ride comfort and safety in high-speed rail (HSR) operation. It is thus critical to understand and track the development of such defects. This study develops an online monitoring system to analyze LCPST deformation at different slab depths under various temperatures. The trackside system, powered by solar energy with STM8L core that is ultra-low in energy consumption, is used to collect data of LCPST deformation and temperature level uninterruptedly. With canonical correlation analysis, it is found that LCPST deformation presents similar periodic variation to yearly temperature fluctuation and large longitudinal force may be generated as heat accumulates in summer, thereby causing track defects. Then the distribution of temperature and deformation data is categorized based on fuzzy c-means clustering. Through the distribution analysis, it is suggested that slab inspection can be shortened to 6 hours, i.e. from 10:00 am to 4:00 pm, reducing 14.3% track inspection workload from the current practice. The price of workload reduction is only a 2% chance of missed detection of slab deformation. The finding of this research can be used to enhance LCPST monitoring efficiency and reduce interruption to HSR operation, which is an essential step in promoting reliable and cost-effective track service.

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