bluuebunny/crossref_metadata_2025 huggingface dataset:
Self‐Representation and Perspectives in Dreams
Authors: Rosen Melanie , Sutton John
Published: November 2013

Integrative and naturalistic philosophy of mind can both learn from and contribute to the contemporary cognitive sciences of dreaming. Two related phenomena concerning self‐representation in dreams demonstrate the need to bring disparate fields together. In most dreams, the protagonist or dream self who experiences and actively participates in dream events is or represents the dreamer: but in an intriguing minority of cases, self‐representation in dreams is displaced, disrupted, or even absent. Working from dream reports in established databanks, we examine two key forms of polymorphism of self‐representation: dreams (or dream episodes) in which I take an external visuospatial perspective on myself, and those in which I take someone else's perspective on events. In remembering my past experiences or imagining future or possible experiences when awake, I sometimes see myself from an external or ‘observer’ perspective. By relating the issue of perspective in dreams to established research traditions in the study of memory and imagery, and noting the flexibility of perspective in dreams, we identify new lines of enquiry. In other dreams, the dreamer does not appear to figure at all, and the first person perspective on dream events is occupied by someone else, some other person or character. We call these puzzling cases ‘vicarious dreams’ and assess some potential ways to make sense of them. Questions about self‐representation and perspectives in dreams are intriguing in their own right and pose empirical and conceptual problems about the nature of self‐representation with implications beyond the case of dreaming.
Context Matters: Studying Indigenous Religions in North America
Authors: King Sarah J.
Published: November 2013

Context is critically important to the study of indigenous religions in North America. This paper argues that the significance of context to indigenous (native, Indian, tribal, or aboriginal) religions is unique and particular. In studying indigenous religions, attending to context engages geographical, political, and methodological issues, which emphasize the diversity of indigenous ideas and experience. The Mi'kmaq relationship to their homeland, Mi'kma'ki, demonstrates the importance of land as fundamental context for indigenous religions; the figure of Kateri Tekakwitha illuminates the inextricably political nature of indigenous religions. Finally, methods, theories, and practices (such as self‐reflexivity) that have arisen in indigenous contexts are important analytical tools in the study of indigenous ways of knowing/practices.
A Sulphur‐crested Cockatoo in fifteenth‐century Mantua: rethinking symbols of sanctity and patterns of trade
Authors: Dalton Heather
Published: November 2013

The earliest image of an Australasian parrot by a European artist predates the arrival of Vasco de Gama's fleet at Calicut on the Malabar Coast in 1498. This article focuses on that image – a small but significant detail in Andrea Mantegna's Madonna della Vittoria, completed in Mantua in 1496. Although Mantegna's altarpiece has been the subject of attention in modern scholarship, the significance of the Sulphur‐crested Cockatoo has not been explored. In this article, I consider why Mantegna would have included parrots in his altarpiece and the symbolic significance of the cockatoo's position in the composition. I also explore the intriguing issue of how a creature native to regions generally considered to have been beyond Europe's trading reach in 1496 could have appeared in a Renaissance artwork. The Sulphur‐crested Cockatoo in the Madonna della Vittoria provides a unique opportunity to place fifteenth‐century Italy in its global context. Its presence not only confirms the interests and purchasing power of Mantegna and his patrons, the Gonzagas, it reveals the complexity and range of South‐East Asian trading networks prior to the establishment of European trading posts in the region.
Leisure Activities and Rural Community Change: Valuation and Use of Rural Space among Permanent Residents and Second Home Owners
Authors: Pitkänen Kati , Adamiak Czesław , Halseth Greg
Published: November 2013

Rural communities are getting more diversified in terms of people's backgrounds, sources of livelihood and interests towards the rural landscape. A common way to discuss rural community change has been to contrast in‐migrants and seasonal residents with long‐term rural residents. In this article, we aim to challenge this segmentation. We ask what it is to be a dweller in the modern countryside and how much the residential status has to do with people's interests and use of space. Based on a postal survey in a case study area in Finland, we look into the differences in the valuation of different leisure activities performed in rural space between second home owners and permanent residents. After dividing permanent residents and second home owners into further subgroups based on their spatial and temporal possibilities to engage in rural leisure, we found that there are no specific activities or groups of activities typical for certain groups of rural leisure space users. Differences between local residents and second‐home owners are rarely explained by this simple dichotomy, rather the differences are better explained by spatial and temporal accessibility.
Sustaining Food Production through Multifunctionality: The Dynamics of Large Farms in Italy
Authors: de Rooij Sabine , Ventura Flaminia , Milone Pierluigi , van der Ploeg Jan Douwe
Published: November 2013

Theoretical approaches to multifunctional agriculture often posit a dichotomy between ‘productivist’ and multifunctional agriculture. However, this theoretical dichotomy runs counter to the tendency among many ‘productivist’ farms to now rely, to varying extents, on newly‐developed multifunctional activities. In this article we identify four of the main controversies within the complex theoretical and political debates about multifunctional agriculture. These concern whether or not multifunctionality is: (1) a survival strategy mostly followed by small and marginal farms, (2) at the expense of food production, (3) primarily driven by governmental programmes, and (4) only relevant at the farm‐level.

We use the results of a representative survey among 795 larger farmers across Italy in order to empirically evaluate these arguments. The research results show that larger farmers are also investing in new, multifunctional activities, alongside investments in food production; in fact, these farmers are keeping pace with, or moving ahead of, farmers who only invest in food production. They consider investments in new activities to be a ‘life‐jacket’ that strengthens their agricultural activities. The results also show that government programmes are not decisive factors for farms engaging in or further developing multifunctional activities. The main drivers are family centred, with some farmers also having ‘broader’ motivations and seeing the wider benefits of multifunctional agriculture.
Problematising the Suicides of Older Male Farmers: Subjective, Social and Cultural Considerations
Authors: Garnham Bridget , Bryant Lia
Published: November 2013

The literature on suicide reveals an academic praxis that largely overlooks the group potentially at highest risk of suicide, namely older male farmers. Within the broader literature on suicide, a small and constrained body of articles has provided empirical evidence and review of the individual risk factors for older male suicides. The rural studies literature on suicide has predominantly focused on the risk factors of suicide for farmers and rural youth and the ways in which masculinities are implicated in suicide. This article engages with these literatures for what they might reveal about the suicides of older male farmers but also critiques their limitations and makes suggestions about potentially revealing avenues for empirical investigation. It argues that the suicides of older male farmers, both real and within discourse, raise complex questions concerning reasons for suicide, embedded within subjective, social and cultural contexts. Examination of cultures of farming masculinity, rural cultures of ageing and the ways in which old age and suicide are problematised may therefore provide critical insights into the suicides of older farming men.
Placing Housing in Rural Development: Exogenous, Endogenous and Neo‐Endogenous Approaches
Authors: Gkartzios Menelaos , Scott Mark
Published: November 2013

This article aims to address the disconnect between housing and rural development research. We do this by examining models of rural development (exogenous, endogenous and neo‐endogenous) in the rural housing context. Drawing on in‐depth documentary analysis of planning and rural development policy and research in the Republic of Ireland, we demonstrate a series of policy failures in implementing exogenous and pseudo‐endogenous approaches to housing policy in rural areas. Subsequently, we propose a neo‐endogenous framework for a more effective integration of housing and rural development theory and practice. In an international context Ireland represents an insightful case for studying the relationship between rural development and housing, due to the emphasis on housing development in rural areas, which in essence has represented a ‘quick fix’ for development, as evidenced by the country's liberal planning regime during an extraordinary housing boom period until the more recent property crash. While the article focuses on Ireland as a case‐study, lessons and a framework for a neo‐endogenous model of rural development and housing are also drawn internationally.
Toward a Critical Race Psychology
Authors: Salter Phia , Adams Glenn
Published: November 2013

Critical Race Theory (CRT) emerged as an identity‐conscious intervention within critical legal studies and has subsequently developed an interdisciplinary presence. We draw upon CRT perspectives to articulate five core ideas for a Critical Race Psychology (CRP). CRT perspectives (1) approach racism as a systemic force embedded in everyday society (rather than a problem of individual bias); (2) illuminate how ideologies of neoliberal individualism (e.g., merit, choice) often reflect and reproduce racial domination; (3) identify interest convergence as the typical source of broad‐based support for reparative action; (4) emphasize possessive investment in privileged identities and identity‐infused realities that reproduce racial domination; and (5) propose practices of counter‐storytelling to reveal and contest identity‐infused bases of everyday society. In summary, we propose a CRP that consider race not as one domain (among many) for psychological investigation but instead as a conceptual lens through which to analyze all of psychological science.
Humble Beginnings: Current Trends, State Perspectives, and Hallmarks of Humility
Authors: Chancellor Joseph , Lyubomirsky Sonja
Published: November 2013

After decades of neglect, research in humility is finally turning a corner. Within the past few years, investigators have articulated two promising strategies to overcome methodological concerns – namely, using personality judgments and designing humility “stress tests” to elicit humility‐relevant behavior. We also highlight an alternative perspective of humility that has not yet gained much attention: the investigation of humility as a state, which helps to understand what humility actually is, how it functions, and its variability within individuals over time. To improve the observation of humility‐relevant behavior, we propose five intrapersonal and interpersonal hallmarks of humility that have strong theoretical support, can distinguish between humility's conceptual foils of narcissism and low self‐esteem, and provide broad theoretical ties between ongoing research endeavors: A secure, accepting identity, freedom from distortion, openness to new information, other‐focus, and egalitarian beliefs. Finally, to increase methodological rigor, we recommend using a combination of self‐reports and other‐reports and employing multiple raters with demonstrated inter‐rater reliability in validation studies.
Nostalgia as a Resource for Psychological Health and Well‐Being
Authors: Routledge Clay , Wildschut Tim , Sedikides Constantine , Juhl Jacob
Published: November 2013

Historically, nostalgia has been viewed as a disease of the brain or the mind. However, in recent years, nostalgia has received a conceptual rehabilitation due to a revival of scholarly interest accompanied by the use of contemporary empirical methods. Drawing upon this recent work, we propose that nostalgia is an important resource for psychological health and well‐being. We begin by detailing the characteristics of the nostalgic experience and then discuss a wide range of studies demonstrating that psychological threat triggers nostalgia, nostalgia enhances psychological health and well‐being, and nostalgia promotes adaptive psychological functioning among individuals at risk for poor mental health. We also highlight the need for future research on nostalgia's relation to psychological health.
Inter‐regulation of the unfolded protein response and auxin signaling
Authors: Chen Yani , Aung Kyaw , Rolčík Jakub , Walicki Kathryn , Friml Jiří , Brandizzi Federica
Published: November 2013

The unfolded protein response (UPR) is a signaling network triggered by overload of protein‐folding demand in the endoplasmic reticulum (ER), a condition termed ER stress. The UPR is critical for growth and development; nonetheless, connections between the UPR and other cellular regulatory processes remain largely unknown. Here, we identify a link between the UPR and the phytohormone auxin, a master regulator of plant physiology. We show that ER stress triggers down‐regulation of auxin receptors and transporters in Arabidopsis thaliana. We also demonstrate that an Arabidopsis mutant of a conserved ER stress sensor IRE1 exhibits defects in the auxin response and levels. These data not only support that the plant IRE1 is required for auxin homeostasis, they also reveal a species‐specific feature of IRE1 in multicellular eukaryotes. Furthermore, by establishing that UPR activation is reduced in mutants of ER‐localized auxin transporters, including PIN5, we define a long‐neglected biological significance of ER‐based auxin regulation. We further examine the functional relationship of IRE1 and PIN5 by showing that an ire1 pin5 triple mutant enhances defects of UPR activation and auxin homeostasis in ire1 or pin5. Our results imply that the plant UPR has evolved a hormone‐dependent strategy for coordinating ER function with physiological processes.
A Wireless, Passive Magnetoelastic Force–Mapping System for Biomedical Applications
Authors: Pereles Brandon D. , DeRouin Andrew J. , Ghee Ong Keat
Published: November 2013

A wireless, passive force–mapping system based on changes in magnetic permeability of soft, amorphous Metglas 2826MB strips is presented for long-term force/stress monitoring on biomedical devices. The presented technology is demonstrated for use in lower-limb prosthetics to ensure proper postoperative fitting by providing real-time monitoring of the force distribution at the body-prosthesis interface. The sensor system consisted of a force-sensitive magnetoelastic sensing strip array that monitored applied loading as an observed change in the peak amplitude of the measured magnetic higher-order harmonic signal of each array element. The change in higher-order harmonic signal is caused by the change in the magnetic permeability of the sensing strips that corresponds to an increase in strip magnetization. After loading, the measured higher-order harmonic signals were fed into an algorithm to determine the applied forces, allowing for determination of the real-time loading profile at the body prosthesis interface.
Abdominal Aortic Aneurysm: From Clinical Imaging to Realistic Replicas
Authors: de Galarreta Sergio Ruiz , Cazón Aitor , Antón Raúl , Finol Ender A.
Published: November 2013

The goal of this work is to develop a framework for manufacturing nonuniform wall thickness replicas of abdominal aortic aneurysms (AAAs). The methodology was based on the use of computed tomography (CT) images for virtual modeling, additive manufacturing for the initial physical replica, and a vacuum casting process and range of polyurethane resins for the final rubberlike phantom. The average wall thickness of the resulting AAA phantom was compared with the average thickness of the corresponding patient-specific virtual model, obtaining an average dimensional mismatch of 180 μm (11.14%). The material characterization of the artery was determined from uniaxial tensile tests as various combinations of polyurethane resins were chosen due to their similarity with ex vivo AAA mechanical behavior in the physiological stress configuration. The proposed methodology yields AAA phantoms with nonuniform wall thickness using a fast and low-cost process. These replicas may be used in benchtop experiments to validate deformations obtained with numerical simulations using finite element analysis, or to validate optical methods developed to image ex vivo arterial deformations during pressure-inflation testing.
Relays to Processors at the Port Authority Trans-Hudson
Authors: Landau Stuart A. , Reitz Daniel J.
Published: November 2013

The Port Authority Trans-Hudson (PATH) heavy-rail rapid-transit system has a two-decade history of using microprocessor-based equipment as replacements for electromechanical and electrical systems. Until recently, these processors were used for non-vital applications only, such as event recording and train dispatching. With the rebuilding of the World Trade Center terminal, processors were introduced for vital applications. PATH is now in the midst of a processor-based replacement of its entire signal system.

Here we present a review of past, current and future applications of processor-based equipment at PATH. We examine the reasons for conversion and the advantages and disadvantages for design, installation and maintenance. A survey is made of equipment that is removed, added, replaced or retained for processor-based conversion. Interfacing with field appliances, including the continued use of relays for limited applications, is examined. With so much functionality concentrated within a single piece of equipment, new types of failure modes and redundancy become important considerations, as well as the volatility of critical information needed to maintain service. We also expose the problems of testing and cutover of new equipment on a railroad that operates passenger service 24 hours a day, 365 days a year, and training requirements of signal office staff and field forces. Since PATH is under FRA jurisdiction, use of processor-based equipment for vital applications is subject to additional regulations and we look at the programming accommodations for FRA testing.
Modeling Capacity of Urban Rail Transit Network Based on Bi-Level Programming
Authors: Hu Jianqiang , Li Haiying , Meng Lingyun , Xu Xinyue
Published: November 2013

Capacity index of Urban Rail Transit (URT) Network plays an improtant role in rational utilization of system capacity and operation management. A definition and calculating method of the capacity of URT Network was first proposed according to the features of URT network and route choice behavior of rail passengers in this paper. Several aspects of influencing factors of URT capacity were analyzed. A bi-level programming model was presented to optimize the URT capacity besides the system utility. Upper level of the model aims at maximizing the total OD flow through the URT network, and the lower level model is one kind of Fisk Equilibrium model. A new kind of impendence function relevant to the lower level model was put forward in consideration of practical traveler behavior. Genetic algorithm technique was applied to solve the bi-level programming model on the premise that the bi-level programming problem be converted into a single-level programming which was achieved by reformulating the lower-level problem model to its equivalent Karush-Kuhn-Tucker conditions. Effective crossover and mutation operators were proposed to enhance the convergence of the Genetic algorithm. A simplified network of Beijing URT was designed and numerical examples were conducted to prove that the proposed model and algorithm are feasible and valid in calculating the capacity of such network.
Application of Operational Modal Analysis on Railway Vehicles Using on Track Measurements
Authors: Erviti Calvo Lara Mª , Agirre Castellanos Gorka , Portillo Igor Alonso
Published: November 2013

Nowadays the application of experimental modal analysis techniques on railway vehicles is gaining importance. A correct identification of modal characteristics allows improving the dynamic behavior design of the vehicle and so reaching higher running speeds and accomplishing better comfort levels. So far, in the railway sector only conventional modal analysis techniques have been used. With these techniques, the modal parameters are determined during a static test by measuring the responses of the system to one or multiple known forces.

This paper presents the application of the Operational Modal Analysis (OMA) technique on a railway vehicle. This technique determines the modal parameters employing only the responses of the system to an unknown excitation. In this way, the data to be used can be acquired during on track test which presents three main advantages. The first one is that the nonlinear components of the suspensions are working in their normal operating condition which is difficult to achieve during a static test. The second one is that the wheel spinning effect is taken into account. Finally, the test can be combined with other type of track tests, reducing the period of time before delivery of the vehicle to the client. In the case under study, the OMA technique is applied by means of commercial software to measurements performed on a passengers train. The modal parameters obtained for the carbody and one of the bogies are presented.
CBTC/ERTMS/PTC Convergence
Authors: Chabanon David
Published: November 2013

A trend has recently emerged in re-signaling projects, especially in Europe, where infrastructure managers of large commuter rails are facing a dilemma: “should we install CBTC (Communication Based Train Control) or ERTMS (European Rail Traffic, Management System) — or both?”

These commuter rails often span over a large territory, interfacing sometimes with the national network and have to cross through high-density traffic sections in crowded cities.

This paper discusses this dilemma and the factors that contribute to the decision-making process of deploying a new signaling system.

These factors, often captured early in the business case of the project, are more complex than the simple issues of a) high throughput capability (leaning toward CBTC) and b) interoperability needs (leaning toward ERTMS).

Other factors are considered in the business case such as: operating needs of the railway including the regulation concepts, reducing the Life Cycle Cost of the system, the risk level that the owner is willing to carry, other high-profile national roll-out plans and special needs of key stakeholders. All of these different factors and parameters are discussed in this paper, and are illustrated by actual re-signaling projects in London, Paris, Madrid and Istanbul.

The main characteristics of ERTMS and CBTC are presented with their pros and cons for these types of applications.

The paper further discusses how the industry is reacting to this emerging trend. Are there any state-of-the-art signaling solutions from the suppliers that can fit these types of projects?

The paper also gives an overview of the recent progress of the European Rail Industry in terms of research and development for future signaling systems in urban / suburban areas.

Meanwhile, Positive Train Control (PTC) systems are being deployed in North America on class 1 railroads as mandated by the US congress, primarily as a means to increase safety. At the same time, some US rail transit agencies are adopting CBTC (albeit at a slow pace). The paper explores if there are any lessons from Europe related to CBTC/ERTMS convergence that could apply in North America related to CBTC/PTC convergence.
Development of Rail Temperature Predictions to Minimize Risk of Track Buckle Derailments
Authors: Bruzek Radim , Biess Larry , Al-Nazer Leith
Published: November 2013

Track buckling due to excessive rail temperature is a major cause of derailments with serious consequences. To minimize the risk of derailments, slow orders are typically issued on sections of track in areas where an elevated rail temperature is expected and risk of track buckling is increased. While the slow orders are an important preventive safety measure, they are costly as they disrupt timetables and can affect time-sensitive shipments. Optimizing the slow order process would result in significant cost saving for the railroads.

The Federal Railroad Administration’s (FRA’s) Office of Research and Development has sponsored the development of a model for predicting rail temperatures using real time weather forecast data and predefined track parameters and a web-based system for providing resulting information to operators.

In cooperation with CSX Transportation (CSX), ENSCO Inc. conducted a model verification study by comparing actual rail temperatures measured by wayside sensors installed on railroad track near Folkston, GA, with the rail temperatures predicted by the model based on weather forecast data over the course of summer 2011. The paper outlines the procedure of the verification process together with correlation results, which are favorable.

The paper also presents results of several case studies conducted on derailments attributed to track buckling. These investigations improve our understanding of conditions and temperature patterns leading to increased risk of rail buckles and validate further use of the Rail Temperature Prediction Model as track buckling prediction tool and as an aid to the railroads in making more informed decisions on slow order issuing process.
Development of a Standard Bond Test for Indented Prestressing Wires
Authors: Arnold Matthew L. , Peterman Robert J. , Bodapati Naga Narendra B. , Beck B. Terry , Wu Chih-Hang (John)
Published: November 2013

An experimental testing program was conducted at Kansas State University (KSU) to test the bond characteristics of various 5.32 mm-diameter, Grade 270 low-relaxation steel wires used in prestressed concrete railroad ties. This un-tensioned pullout test could serve as a quality control test similar to the NASP (North American Strand Producers) Strand Bond Test that has been developed for pre-tensioned strands. A total of twelve (12) wires produced by six different steel manufacturers were used to develop the wire pullout test. All of the wires were tested in their “as-received” condition and have different indent geometries. It is generally accepted that indentations in the wire improve the bond between the steel and concrete. However, there are currently no commonly accepted quality control tests that accurately predict a wire’s bond characteristics in a pre-tensioned application.

The un-tensioned pullout test developed is comparable to the NASP [Strand] Bond Test. The specimens consist of a 4 in. (100 mm) outer-diameter tube with a total length of 8 in. (200 mm) and a steel plate welded to the bottom. The 5.32 mm-diameter wire was centered in the tube and the sand-cement mortar was placed and allowed to cure. The flow of the mortar was measured for consistency and 2” × 2” (50 mm × 50 mm) mortar cubes were used to determine the compressive strength of the mortar. The specimens were tested when the compressive strength of the mortar was between 4500 and 5000 psi (31.0 MPa and 34.5 MPa). Each batch of mortar contained 12 pullout specimens; one with each wire type. Each wire was tested six times leading to a total of six batches and a total of 72 mortar specimens.

During testing, the wires were loaded in force control at the bottom, while continuously monitoring and recording the movement (slip) of the wire with respect to the mortar at the opposite (top) end. The force verses end-slip data of the six tests for each wire type were numerically combined to obtain the average bond performance. These average results from the un-tensioned pullout tests were then compared to transfer length measurements from accompanying pre-tensioned concrete prisms. In general, the wire end slip measurements from the pullout tests were found to have good correlation with the measured transfer length. For all 12 wires, a coefficient of determination (R2) of 0.872 was found between the average pullout force (at 0.10-inch (2.54 mm) of wire free-end slip) and average transfer length measurements from the accompanying concrete prism tests. However, when only the indented wires were considered, the R2 increased to 0.913.
Autonomous Train Control and Track Circuit Inspection System
Authors: Meunier Jeffrey K. , Rolin Amaury
Published: November 2013

The Washington D.C. Metro utilizes an Automatic Train Control (ATC) system designed in the mid 1970’s. This ATC system employs passive track bed markers and antennas inductively coupled to the track to send and receive audio frequency control signals over the rails. The ATC system is only installed in revenue passenger cars and has never been installed on any other vehicle. Recently, a new inspection vehicle was delivered that includes an inspection module that interfaces with this train control system to inspect the control and track occupancy signals.

This paper will discuss the challenges of designing a track circuit inspection system and retrofitting a refurbished ATC system designed for a revenue vehicle to a custom self propelled inspection car to ensure uniform inductive coupling over curved track, maintaining dynamic clearance envelop of the inspection car and design of custom broadband signal antennas to prevent interference. Additionally this paper will discuss the technical approach for conducting the inspection and results achieved during testing.
Influence of Indented Wire Geometry and Concrete Parameters on the Transfer Length in Prestressed Concrete Crossties
Authors: Bodapati Naga Narendra B. , Zhao Weixin , Peterman Robert J. , Wu Chih-Hang John , Beck B. Terry , Haynes Mark , Holste Joseph R.
Published: November 2013

A study was conducted to determine the variation in the transfer length of prestressed concrete railroad ties with different indented wire geometries and different concrete properties, including slump and release strength. The study included 12 different reinforcement wire types that are used in concrete railroad ties worldwide.

This paper presents the results from transfer length measurements on 96 pretensioned concrete members that were cast in the laboratory. In order to replicate the wire-to-concrete proportions commonly used in prestressed concrete railroad ties, small (3 1/2″ (88.9 mm) × 3 1/2″ (88.9 mm)) prestressed concrete prisms were fabricated and each contained four 5.32-mm-diameter indented wires. A special jacking arrangement was used to ensure that each of the wires was tensioned to the same jacking force.

The wires were initially tensioned to 7000 pounds (31.14 kN) each, and the transfer of prestress force into the members was accomplished by a gradual release method replicating the one used in most prestressed concrete crosstie manufacturing plants. The study consisted of two phases. In the first phase, 36 concrete prisms were cast to investigate the effect of different wire indent geometry in a 6-inch (152.4mm) slump concrete mix with 4500 psi (31.03 MPa) release strength.

In the second phase, a total of 60 prisms were used to investigate the effect of 4 different concrete parameters with a select group of 5 indented wire types. The second phase included concrete release strengths of 3500 psi (24.13 MPa) and 6000 psi (41.37 MPa), and concrete consistencies (slumps) of 3 (76.2) and 9 inches (228.6 mm).

The results have shown that there is a significant variation in transfer lengths for the different indented wires at the same release strength. Additionally, the results show that the transfer lengths decreased significantly with modest increases in the concrete release strength. However, there was no correlation observed between transfer lengths and different concrete slumps for mixes having the same water-to-cementitious (w/c) ratio. For each concrete pour, the splitting tensile strength and modulus of elasticity were measured at the time of prestress transfer. All wire indents were measured according to ASTM A-881 [1] and the results of both phases are presented.
Understanding Stray Current Mitigation, Testing and Maintenance on DC Powered Rail Transit Systems
Authors: Memon Saud
Published: November 2013

All direct current traction power systems using rails for return of traction current have a level of current leakage. This leakage of current is dependent on both design and operating factors affecting the efficiency of the rail return path and is referred to as stray current. Stray currents have been detected since the first electric railways were placed into operation during the latter half of the nineteenth century and have serious effects on utility structures and the neighboring infrastructure at large. Stray currents can create safety hazards thereby rendering the design of stray current mitigation an important element of the overall design of a rail transit system.

Like any other design/construction project, a baseline survey is an important and significant step in the data collection and fact finding process for a light rail system. Such a survey would aid in finding the soil resistivity data and the results of the stray current levels on existing buried metal utilities. Similarly defining the design criteria for stray current mitigation, monitoring, and testing for a new light rail design project is also important. Most of the design criteria for the older rail transit systems have been developed as an aftermath of the corrosion problem and/or after the design of new extension to the system. Some older transit systems still do not have a specified design or mitigation criteria for stray current, and corrosion issues are handled as they surface and are prioritized based on severity. In the absence of guidelines, it is hard to understand the reasoning behind the limiting criteria suggested in the transit agency manuals particularly when there is no record of testing or soil resistivity investigation. For these older transit systems the limiting criterion was developed based on the information from other transit services. Having applicable design criteria for stray current control and mitigation will help standardize the process for the transit and will lower the cost of mitigation.

This paper has been written by a Civil Engineer with an effort to understand the source and the scientific reasoning behind the limiting values suggested by the transit agencies associated with stray current testing procedures and its control. In order to understand the limited stray current corrosion criteria and the respective testing, various transit agencies were interviewed. These interviews were supplemented by a thorough review of the respective transit agency criteria manual/guidelines (where such information was available and accessible). Critical evaluations of the testing procedures were conducted to analyze if these tests and mitigation methods were effective.
Seismic Testing for Track Substructure (Ballast and Subgrade) Assessment for Passenger/Freight Corridors
Authors: Stark Timothy D. , Nazarian Soheil , Ho Carlton L. , Tutumluer Erol
Published: November 2013

This paper presents the research framework and preliminary findings from a recently started Federal Railroad Administration (FRA) sponsored research project at the University of Illinois at Urbana-Champaign on developing and using seismic wave propagation principles to develop a track substructure (ballast and subgrade) condition assessment system. This condition assessment system will be used to evaluate track safety and to predict inspection intervals. This research is needed because there is no tool or system available that quantitatively measures the mechanics based properties of the layers comprising a track system. These mechanics based properties are shear modulus, modulus of deformation (Young’s modulus), and shear strength that can be derived from direct measurement of the shear wave velocity profile. Currently the modulus and shear strength of the track system materials are usually estimated which leads to uncertainty in the numerical analyses and estimates of track safety.
A Study on Determination of Electrical Impedance and Frequency Characteristics of a Subway System Using Finite Element Analysis
Authors: Deleanu Sorin , Carpenter David C.
Published: November 2013

The paper provides a description of the analysis of a subway system (track-in-tunnel) by using FEM analysis and comparing to classical analytical approaches by Carson, Pollaczek, Bickford and Tylavsky.

Reviews of methods to determine self and mutual impedance for electrified railroads are provided. These methods include frequency response and are directly applicable to a three-rail track DC track system.

The analytic impedance models are built on Carson-Pollaczek–Bickford equations, adjusted by Tylavsky, for two situations: when the ground is perfectly insulated and when considering the earth return current. For the latter, the authors assume a return current path only through the tunnel concrete structure below the railway track support structure. The model is extended by considering the effects of the soil beneath under tunnel as a conductor.

The solution of finite element method (FEM) applied for the determination of impedance for the three-rail track subway train configuration, modeled and examined, consists of computational analysis based upon minimizing the energy of electromagnetic field.

The paper continues by examining the frequency effects on the track and system. The track/trolley model developed by Tylavsky was modified such that the trolley feeder is provided by the power rail and used to calculate the return current through the traction rails. The subway train, supplied with a rectified DC power, is subjected to a significant harmonic content, which may affect the signal and control circuits.

Both experimental data and preliminary analytical and numerical calculations are presented, showing the variation of resistances and inductances of the running track with the current magnitude and frequency response. In the study, a large frequency range was considered (15Hz to 5000Hz) in order to cover all of the significant frequencies used for control and signal systems in common tracks configurations, and for which measurements have been carried. It is then shown that the power and signaling characteristics of the modeled system can predict the magnitude of the perturbation current for different values of frequency. The current density profile is illustrated for the case of a concrete tunnel structure in a subway application.

The last section consists of a discussion regarding future developments and further work.
Multifunction LIDAR Sensors for Non-Contact Speed Measurement in Rail Vehicles: Part I — System Installation and Implementation
Authors: Muñoz Joshua , Craft Michael , Ahmadian Mehdi , Wrobel Shannon
Published: November 2013

This study presents speed measurement system using Light detection And Ranging (LIDAR) technology is successfully tested on moving railway cars. The system has multiple mounting capabilities that allow it to attach to various locations on the railcar. Using lasers to measure train speed off of each rail individually, the system determines curvature characteristics of the track based on known track geometry and speed differentials measured by the system. The LIDAR speed measurement system offers a non-contact form of measurement that eliminates noise and unwanted disturbances originating from contact sensors such as wheel-mounted encoders. The results of the study indicate that, with an ability to operate at speeds from 0.5mph and upwards of 100mph, the LIDAR system proves to be a highly versatile and precise measurement device useful in rail geometry measurement applications.
Consequences of Failed Track Circuits on Conventional Signaling System in CBTC Projects
Authors: Diemunsch Kenneth M. , Reitz Daniel J.
Published: November 2013

In recent years, many rapid mass transit agencies have chosen Communication Based Train Control (CBTC) technology to refurbish their signaling system or to equip a new line. CBTC technology is a type of Automatic Train Control (ATC) that allows transit agencies to increase nominal throughput and to improve safety. The main functions of CBTC are described in [1.] and [2.].

This technology can operate without fixed wayside track detectors such as track circuits. However, track circuit equipment continues to be implemented on the tracks and in the equipment rooms. For authorities under the Federal Railroad Administration, current regulations require use of track circuit but the main functional reason is to have a backup system in case of CBTC failure. Most transit agencies decide to include track circuit occupied and vacant status into the CBTC system in order to enhance safety. How to enhance safety and keep train operation efficient during track circuit failure is a challenge for CBTC projects.

This paper discusses the relationship between the CBTC and the conventional interlocking system when track circuit failure occurs. The analysis in this paper applies to both relay and solid state interlocking systems as both technologies have to deal with the same impact under this scenario. The method of detection of track circuit failure by the CBTC system and the possible restrictions on CBTC train operation are not presented. The paper focuses on the interface between the CBTC and the signaling system. It begins by introducing the different types of track circuit failures and their consequences on conventional signaling system to address and compare multiple scenarios. Then, the paper discusses how the CBTC system can affect the conventional signaling system equipment, such as signals and train stops, once it has detected a track circuit failure. Transit agencies’ different possible approaches to manage track circuits failures within the context of an operating CBTC system are explained.
The Application of Track Spectrum Applying to Track Dynamic Analysis
Authors: Li Cheng-hui , Chen Bo-jing , Liu Yu-tao , Dai Feng
Published: November 2013

The track irregularity is the primary cause to induce the vibration of the wheel-rail system. With the statistical characteristics of track irregularity, the track spectrum is widely applied to the track dynamic analysis. The track spectrum and its application are discussed in this paper mainly from the three aspects as follows.

1. Due to the multiple types of track structure, the statistical features of the track irregularity are varying, thus the original type and wavelength of the track spectrum cannot interpret the current situation.

2. As for the track dynamic analysis, because of the lack of the important short wave track irregularity spectrum, the track high-frequency vibration can hardly be further analysed with the existing track spectrum.

3. When the track irregularity in time domain included in the track spectrum for track dynamic analysis is used, there exists the problem that the amplitude of responses tends to be smaller than the actual situation.

To sum up, this paper further put forward some suggestions about optimizing the test work of the supplementary track spectrum and reasonably utilizing the track spectrum.
Selected In-Track Applications and Performances of Hot-Mix Asphalt Trackbeds
Authors: Rose Jerry G.
Published: November 2013

The use of a layer of asphalt within railway trackbeds has steadily grown since the early 1980s in the United States. Its primary use has been for maintenance and rehabilitation applications in existing tracks, particularly at special trackworks, to improve trackbed performance, and to a lesser extent for new trackbed applications where the projected long-term performance of the asphalt trackbed is anticipated to be economically justified. Normally the asphalt layer is 6 in. (150 mm) thick, placed on a prepared subgrade or granular subballast, and is subsequently topped with a layer of typical ballast. Accepted highway/railway construction practices are adhered to, including adequate preparation and compaction of the support layers. In addition, surface and sub-surface drainage aspects are evaluated on a site-specific basis and improvements are specified based on accepted engineering practices. This application does not deviate significantly from conventional all-granular trackbed designs, except the asphalt layer is substituted for a portion of the thickness of the granular subballast and ballast support materials.

Described herein are 1) typical trackbed designs, 2) in-track applications, and 3) long-term performance evaluations for various types of major applications on several U.S. Class I railroads, namely NS, UP, CSX, and BNSF, and a limited number of Shortline railroads. Specifically addressed are rehabilitation applications for special trackworks — tunnel floors/approaches, wheel impact load detectors, bridge approaches, rail-highway crossings, turnouts, rail crossings, and rail crossovers — plus descriptions for a limited number of new double-tracking open-track installations. Brief descriptions are provided for international applications in six countries.

Particular detail is given to factors affecting the economic justification for utilizing this technology based on long-term performances and historical evaluations of numerous installations. Details are provided relative to unique conditions and logistics related to the application of the layer of asphalt within the trackbed support for the special trackworks and selected open-track installations. Several specific installations are highlighted.
Effect of Wheel Truing on Wheel Rim Axial Residual Stress
Authors: Lonsdale Cameron , Oliver John
Published: November 2013

Recent x-ray diffraction testing of wheels with machined treads showed that axial residual stresses in the wheel rim were different than the axial residual stresses in Vertical Split Rim (VSR) wheels, and service worn wheels with no machining. As a result, a larger study was conducted at the wheel shops of major North American railroads. Tread damaged wheelsets were machined to remove tread damage and restore the flange/tread profile. The amount of metal removed from the treads was recorded, wheels were demounted, and slices were removed from the machined wheel rims at pre-marked areas for x-ray diffraction testing. The wheel rim axial residual stress patterns for the machined wheels are presented and are compared to the axial residual stress patterns for VSR wheels and used wheels with no machining. Data are presented for both forged and cast wheels. Implications for improved service performance from reduced tread damage are also discussed.