LATEST ARTICLES
Details of the latest articles published in the Journal. Includes the most recent InPress papers (uncorrected proofs of accepted papers awaiting publication in a Journal issue).
Date: Thu, 18 Mar 2010 14:51:35 GMT
This paper reports on tools and methods used to analyse and present information for long-, medium-, and short-term planning and fleet condition supervision to predict and manage wheel–rail performance. Challenges in addressing measuring accuracy and repeatability are also discussed.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT339
- Authors
Date: Thu, 18 Mar 2010 14:51:33 GMT
Timber track steel girder railway bridges in service for many decades have been damaged and deteriorated despite the regular scheduled maintenance owing to their structural characteristics, calling for alternates to improve the structural safety and serviceability. In this study, the authors aim to develop precast slab panel (PSP) tracks to enhance the long-term workability and durability of existing bridges in service so as to improve the performance of conventional lines. Two full-scale specimens with a timber track and a PSP track were fabricated to evaluate the effects of the application of the PSP track, and static and dynamic tests were conducted. Also, a time-history analysis and a three-dimensional finite-element method analysis were performed to consider the train speed and the effect of multiple loads of train. From the results, the static and dynamic responses of the PSP track girder were significantly reduced, compared with the timber track girder.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT333
- Authors
- J-Y Choi, Institute of NewRail, Graduate School of Railway, Seoul National University of Technology, Nowon-Gu, Seoul, Republic of Korea
- Y-G Park, Department of Railway Construction Engineering, Graduate School of Railway, Seoul National University of Technology, Nowon-Gu, Seoul, Republic of Korea
- E-S Choi, Department of Civil Engineering, Hongik University, Seoul, Republic of Korea
- J-H Choi, Railway Division, Technology Institute of DaeHan Consultants, DaeHan Consultant Co., Ltd, JongRo-Gu, Seoul, Republic of Korea
Date: Thu, 18 Mar 2010 14:51:33 GMT
In order to develop more durable wheel materials to cope with the new specifications being imposed on wheel wear, a greater understanding of the wear mechanisms and transitions occurring in wheel steels is needed, particularly at higher load and slip conditions.
The aim of this work was to draw together current understanding of the wear mechanisms, regimes, and transitions (particularly with R8T wheel material) and new tests on R7T wheel material; to identify gaps in the knowledge; and to develop new tools for assessing wear of wheel materials, such as wear maps, that can be used to improve wear prediction. Wear assessment of wheel materials, as well as wear rates, regimes, and transitions, is discussed.
Twin disc wear testing, used extensively for studying wear of wheel and rail materials, has indicated that three wear regimes exist for wheel materials: mild, severe, and catastrophic. These have been classified in terms of wear rate and features. Wear rates are seen to increase steadily initially and then level off, before increasing rapidly as the severity of the contact conditions is increased.
Analysis of the contact conditions in terms of friction and slip has indicated that the levelling off of the wear rate observed at the first wear transition is caused by the change from partial slip to full slip conditions at the disc interface. Temperature calculations for the contact showed that the large increase in wear rates seen at the second wear transition may result from a thermally induced reduction in yield strength and other material properties. Comparisons made between discs and actual wheels have provided some support for the theories relating to the transitions observed.
Wear maps have been produced using the test results to study how individual contact parameters such as load and sliding speed influence wear rates and transitions. The maps are also correlated to expected wheel–rail contact conditions.
This improved understanding of wheel wear mechanisms and transitions will help in the aim of eventually attaining a wear modelling methodology reliant on material properties rather than on wear constants derived from testing.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT328
- Authors
- R Lewis, Department of Mechanical Engineering, The University of Sheffield, Sheffield, UK
- R S Dwyer-Joyce, Department of Mechanical Engineering, The University of Sheffield, Sheffield, UK
- U Olofsson, Department of Machine Design, KTH, Stockholm, Sweden
- J Pombo, IDMEC/Instituto Superior Técnico, Technical University of Lisbon, Lisbon, Portugal
- J Ambrósio, IDMEC/Instituto Superior Técnico, Technical University of Lisbon, Lisbon, Portugal
- M Pereira, IDMEC/Instituto Superior Técnico, Technical University of Lisbon, Lisbon, Portugal
- C Ariaudo, Running Dynamics, ALSTOM Ferroviaria s.p.a., Savigliano (CN), Italy
- N Kuka, Running Dynamics, ALSTOM Ferroviaria s.p.a., Savigliano (CN), Italy
Date: Thu, 18 Mar 2010 14:51:33 GMT
Leaf contamination has been identified as the major cause of low adhesion incidents occurring on some railway networks in the last few decades. In the presence of leaf layers, the trains cannot have the required adhesion at the wheel–rail contact for adequate traction and braking operation. Under these circumstances, not only the punctuality but also the safety of the railway transportation can be threatened. In order to mitigate low adhesion problems, railway organizations have opted for different measures, particularly in Autumn. The most employed measure consists of bringing sand to the wheel–rail interface, which can be performed by means of air-pumped sanders or in the form of sand-based friction modifiers. Although sand has widely been accepted as an effective adhesion improver, the effect of some sanding parameters on the adhesion improvement in leaf-contaminated contacts seems to be unclear. This hinders the possible optimized use of sand on the railway networks. In this paper, the influence of the number of sanding axles, particle size of sand, and wheel slip on the adhesion recovery in leaf-contaminated wheel–rail contacts is presented. Rolling–sliding tests under closely controlled conditions have been performed on a twin-disc roller rig. An electrical circuit has been connected to the rig for monitoring the effect of contamination on the electrical conductivity across the wheel–rail contact. The results show that the application of sand contributes to removing the leaf layers from the discs surfaces, which leads to a higher adhesion coefficient in comparison with the untreated (baseline) situation. Accordingly, the electrical conductivity across the wheel–rail contact is also improved. Furthermore, the adhesion recovery is shown to become larger and faster with the increase in sanding axles and wheel slip. Among the particle sizes tested in this work, medium particles are found to yield the most effective adhesion recovery.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT308
- Authors
- O Arias-Cuevas, Section of Road and Railway Engineering, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft, The Netherlands
- Z Li, Section of Road and Railway Engineering, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft, The Netherlands
- R Lewis, Department of Mechanical Engineering, The University of Sheffield, Sheffield, UK
- E A Gallardo-Hernández, Department of Mechanical Engineering, The University of Sheffield, Sheffield, UK
Date: Fri, 12 Feb 2010 17:14:04 GMT
The Korea High-Speed Train (KHST) is complete and ready for commercial service. In preparation for commercial service, the reliability of the KHST was proved. In this article, a practical procedure is proposed to assess and manage the reliability of the prototype train traction system. The past data of a similar traction system are analysed in order to set the reliability target. The effectiveness of the procedure for reliability growth is shown. After the electric traction system is classified into subsystems, reliability analysis is carried out. Reliability block diagram and failure mode effect analyses are performed. The expressions for calculating the reliability are deduced and the mean kilometres between service failures are calculated using the previous failure rate data. Some practical criteria for the demonstration of reliability are proposed. Reliability growth is shown using a test run on a commercial line.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT297
- Authors
- S Il Seo, Planning and Policy Division, Korea Railroad Research Institute, Uiwang-City, Gyeonggi-Do, Republic of Korea
- C S Park, High Speed Rail Division, Korea Railroad Research Institute, Uiwang-City, Gyeonggi-Do, Republic of Korea
- S H Choi, High Speed Rail Division, Korea Railroad Research Institute, Uiwang-City, Gyeonggi-Do, Republic of Korea
- Y J Han, High Speed Rail Division, Korea Railroad Research Institute, Uiwang-City, Gyeonggi-Do, Republic of Korea
- Ki H Kim, High Speed Rail Division, Korea Railroad Research Institute, Uiwang-City, Gyeonggi-Do, Republic of Korea
Date: Fri, 12 Feb 2010 17:14:04 GMT
Railways are expected to operate with ever increasing availability. The availability of railway systems and subsystems influences the overall operational availability. As the track circuit is a key component of railway signalling and control, it can contribute significantly to the loss of availability of the railway system. One way to increase the availability of the track circuit is by implementing a proper maintenance policy. In this article, Petri-Nets have been used to develop models for availability analysis of the track circuit for both time-based and condition-based maintenance. A sensitivity analysis has been performed to estimate the effect of maintenance parameters on availability performance using cost–benefit analysis.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT296
- Authors
Date: Thu, 07 Jan 2010 17:08:15 GMT
During the operation of a high speed railway vehicle, safety is a basic requirement. However, due to the potentially large lateral displacements of the wheelsets, the precise mechanism of derailment is different from conventional vehicles and not fully understood. To obtain correct simulation results for this behaviour it is necessary to select methods for rapid and exact computation of the creep forces, the normal force, and the three-dimensional geometry at each contact point. In this paper, a dynamic model is presented and two types of derailment have been thoroughly investigated. High lateral force is used as a criterion for determining the critical point at which flange climb occurs and the critical speed for impact derailment is derived using the oblique-impact theory. Finally, an assessment method is proposed which distinguishes between the two types of derailment. The simulation model can also be used to identify the factors that lead to greatest risk of derailment.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT277
- Authors
Date: Thu, 07 Jan 2010 17:08:15 GMT
This article presents a dynamic computational model for analysing the correlation between rail's natural frequencies and the longitudinal stress generated by temperature variation. The model includes a rail, sleepers, and the foundation. Some factors such as the rail section profile, rail wear, and the stiffness of fasteners are also considered. Based on the model, numerical computational analyses are performed. The relationship between the rail's longitudinal temperature force and the natural frequency is also studied. The influences of parameters such as the wear of the rail, unsupported distance of adjoining sleepers, fastener stiffness, rail types, and foundation stiffness are investigated. A field experiment is also presented that was performed to investigate the relationship between the rail's dynamic characteristics and the longitudinal stress generated by temperature variation with various unsupported sleeper spacings. The results of analysis and in-field measurements are compared.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT290
- Authors
- Y Luo, Railway and Urban Mass Transit Research Institute, Tongji University, Shanghai, People's Republic of China
- L Li, Railway and Urban Mass Transit Research Institute, Tongji University, Shanghai, People's Republic of China
- H Yin, Université Paris-Est, UR Navier, Ecole Nationale des Ponts et Chaussées, Champs sur Marme, Marne la Vallée Cedex, Paris, France
Date: Tue, 08 Dec 2009 06:02:21 GMT
Pre-assembled turnouts have recently been introduced with split concrete sleepers joined by elastic coupling plates. Their effect on the forces, vibration response, and sound radiation as trains run through a turnout is studied here using a calculation model for a whole turnout based on the finite-element method. The non-linear characteristics of the ballast's support under the sleepers, as well as the special construction of the articulated joints, are included. It is shown that compared with the normal integral sleeper design, the track with articulated switch sleepers has a lower rigidity, which changes more evenly along the track and improves its dynamic performance. Furthermore, the fatigue strength of an articulated switch sleeper is higher due to its lower stress amplitudes. Additionally, when the vehicles are running on the main turnout route, as the switch sleepers’ vibration behaviour is modified, the articulated joints effectively reduce the impact loading of the ballast at the end of the sleeper under the turnout branch track. This will extend the life of the ballast bed. Finally, the sound radiation from the articulated switch sleeper is very low in the hinged short part and is reduced by about 0.6 dB for the total length.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT302
- Authors
- J Y Zhu, Institute of Railway and Urban Mass Transit, Tongji University, Shanghai, People's Republic of China
- D J Thompson, Institute of Sound and Vibration Research, University of Southampton, Southampton, UK
Date: Tue, 08 Dec 2009 06:02:20 GMT
Train formation planning models determine the routing and frequency of trains and assign the wagons to trains. In this article, a new robust mixed integer model for the train formation problems is proposed where the input data are subject to uncertainty. The optimal solution of the proposed model of this article is believed to be difficult to determine and a heuristic approach to find the near-optimal solution is presented. The implementation of the proposed model of this article is demonstrated for a real-world case study and the results are discussed.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT295
- Authors
- M A Shafia
- S J Sadjadi
- A Jamili
Date: Tue, 08 Dec 2009 06:02:18 GMT
Recent experience with the operation of high-speed railways in the UK and elsewhere has revealed the phenomenon, termed ‘ballast flight’, of ballast particles becoming airborne during the passage of trains, potentially causing damage to both the railhead and the vehicle. This article reports the results of an investigation into the mechanical and aerodynamic forces acting on ballast particles that are generated during the passage of a high-speed train and addresses the question whether these might offer a possible explanation for the initiation of ballast flight. As the high-speed trains passed, measurements were made of the air pressure and velocity at various locations across the track, and of the velocity and acceleration of the track system (sleeper and rails) and the ballast itself. The aerodynamic forces exerted on a suspended ballast particle were also measured. An analytical model of the behaviour of small ballast particles was constructed to assist in the interpretation of the measured data. Analysis of the data and modelling suggest that neither mechanical forces nor aerodynamic forces in isolation are likely to be sufficient to initiate ballast flight under the conditions investigated, but that the phenomenon could arise from a combination of the two effects. It appears that the process is stochastic in nature: further work, with an increased number of measurements, is required to explore this.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT294
- Authors
- A D Quinn, Centre for Railway Research and Education, School of Civil Engineering, University of Birmingham, Edgbaston, Birmingham, UK
- M Hayward, Channel Tunnel Rail Link, Network Rail, London, UK
- C J Baker, Centre for Railway Research and Education, School of Civil Engineering, University of Birmingham, Edgbaston, Birmingham, UK
- F Schmid, Centre for Railway Research and Education, School of Civil Engineering, University of Birmingham, Edgbaston, Birmingham, UK
- J A Priest, School of Civil Engineering and the Environment, University of Southampton, Southampton, UK
- W Powrie, School of Civil Engineering and the Environment, University of Southampton, Southampton, UK
Date: Fri, 18 Sep 2009 15:48:02 GMT
Railway construction projects involve major capital investments, and a slight variance in design could lead to a significant change in the total project cost. To achieve value for money, it is necessary to optimize the design as far as possible. However, in reducing costs, it is important that key project objectives such as system capacity and operational flexibility are not sacrificed. In this article, a value engineering methodology, with particular emphasis on maintaining project objectives and requirements, is introduced. It involves identifying major cost drivers, devising explicit knowledge representations for these cost drivers, and analysing how they could be optimized without compromising key requirements such as the passenger-carrying capacity. The methodology is illustrated using real-world examples taken from the West Rail project in Hong Kong, which was originally conceived to be a twelve-car railway and subsequently optimized to become a seven-car system initially, with provisions to grow into an eight-car and then a nine-car configuration, without compromising the planned carrying capacity. The savings achieved were in the order of billions of Hong Kong dollars. One novel aspect of the proposed methodology is the development of a structured representation for a cost driver, through which non-obvious but significant savings could be derived.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT291
- Authors
- E C S Kwok, MTR Corporation, Hong Kong, People's Republic of China
- P M Anderson, Vision Skills Consulting Limited, Hong Kong, People's Republic of China
- S H S Ng, Atkins China Limited, Hong Kong, People's Republic of China
Date: Fri, 18 Sep 2009 15:48:02 GMT
Climate change predictions suggest a trend towards hotter drier summers in the UK. At extreme high temperatures the railway network is prone to dangerous, damaging, and expensive rail buckles. In order to reduce the risk of a rail buckle, emergency speed restrictions are introduced which can be costly. This article presents a quantification of the effects of higher summer temperatures due to climate change on the UK railway network. A combination of analogue techniques and a weather generator are used to establish trends between heat-related delays and temperatures. Costs are assigned to the change in frequency and severity of delays and evidence-based recommendations are made for future operations. The results demonstrate that the costs incurred as a result of the hot summer of 2003 will become typical in the 2050s (high emissions scenario) and 2080s (low emissions scenario). If no changes are made to maintenance regimes, it is estimated that the total costs of heat-related delays will eventually double to nearly £23 M during extreme summers.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT292
- Authors
- K Dobney, School of Engineering, University of Birmingham, Birmingham, UK
- C J Baker, School of Engineering, University of Birmingham, Birmingham, UK
- L Chapman, School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK
- A D Quinn, School of Engineering, University of Birmingham, Birmingham, UK
Date: Wed, 02 Sep 2009 20:50:19 GMT
Early attempts at monitoring the condition of railway point mechanisms employed simple thresholding techniques to detect faults, but success was limited and there were large numbers of false alarms and missed failures in the field. More recent research using data collected from line-side equipment and lab-based test rigs, though, is suggesting that it should indeed be possible to predict failures with sufficient accuracy and notice to be of genuine use to infrastructure maintainers and owners. This review into state-of-the-art predictive fault detection and diagnosis methods shows how some very different generic models have been tailored to the various types of mechanisms that are in use worldwide. In any specific case, the most appropriate combination of quantitative and qualitative techniques will be determined by the inherent failure modes of the system and the particular conditions under which it operates. Furthermore, it is vital to have a priori knowledge of the symptoms that are observable under fault conditions if diagnosis is to be reliable.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT289
- Authors
- F P García Márquez, ETSII de Ciudad Real, Universidad de Castilla-La Mancha, Spain
- C Roberts, Birmingham Centre for Railway Research and Education, University of Birmingham, Edgbaston, UK
- A M Tobias, Birmingham Centre for Railway Research and Education, University of Birmingham, Edgbaston, UK
Date: Wed, 12 Aug 2009 14:25:20 GMT
Issues regarding capacity and service quality of metro lines have been receiving attention in worldwide transportation circles recently. Because investment in metro infrastructure is costly, increasing capacity utilization of existing systems while maintaining service quality, particularly in environments where disturbance occurs frequently, is a challenge. For highly homogeneous railway systems such as metro lines, the robustness of the train regulation system against disturbances is an important factor affecting capacity utilization and service quality. Train regulation in metro lines is essentially a highly non-linear, stochastic, and constrained optimization problem. This article proposes an automatic train regulation (ATR) design using dual heuristic dynamic programming (DHP). The ATR system makes easier the handling of the non-linear and stochastic characteristics of metro line with infrastructure constraint; and near-optimal regulation can be obtained more rapidly and accurately. The verification of the DHP-based ATR referring to practical operation data of Taipei metro is presented, and a comparison with a design using linear quadratic regulator is also provided, especially regarding robustness against disturbance.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT283
- Authors
- W-S Lin, Department of Electrical Engineering, National Taiwan University, Taipei, Republic of China
- J-W Sheu, Department of Electrical Engineering, National Taiwan University, Taipei, Republic of China
Date: Fri, 24 Jul 2009 15:47:39 GMT
Transition curves play an important role in riding quality, especially for high-speed railways. Accordingly, various curves have been proposed as transition forms. To evaluate the effects of the forms in transition curves, the basic requirements and forms of transition curves were first discussed, and then simulations were performed with several typical transition curves at various speeds, based on the dynamic model developed in this research. The results indicate that the dynamic effects of transition curves are determined by the curvature variation and the order of the curvature derivative that is equal to zero at the curve endpoints, while the expression mode (such as algebraic or trigonometric expression) does not make much difference. From a dynamic viewpoint, the ideal transition form requires that the second derivative of its curvature is equal to zero at the curve endpoints at least, such as the seventh parabola, ninth parabola, and sinusoid, with which the vibration accelerations of the vehicle vary smoothly and the jerk can be effectively eased. Then the appropriate transition forms are recommended for ordinary and high-speed railways, respectively.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT287
- Authors
- X-Y Long, School of Civil Engineering, Beijing Jiaotong University, Beijing, People's Republic of China
- Q-C Wei, School of Civil Engineering, Beijing Jiaotong University, Beijing, People's Republic of China
- F-Y Zheng, School of Civil Engineering, Beijing Jiaotong University, Beijing, People's Republic of China
Date: Thu, 16 Jul 2009 18:47:54 GMT
The accuracy of the simulation of train–track interaction can be improved by adding a node at the point of loading, when a contact force exists within the beam element that models the rail. This causes difficulties in the formulation and entails large computational times since the node moves along with the point of contact. In this study, a more simplified method that can represent the discontinuities of slope deflection at the location of both the sleeper and of the moving contact force, while employing the customary finite-element method, has been presented. The simulation of the existence of such an added node without explicitly including it is realized by modifying the Hertzian spring coefficient and adding the additional mass matrix to the existing mass matrix. Also, to enhance the convergence and to overcome the computational burden of load vector calculations at all iterations, a modified Newmark-β integral scheme is proposed. The suggested model was validated by comparing the results with field-test data and other numerical models reported in the literature by other researchers.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT285
- Authors
Date: Mon, 29 Jun 2009 14:52:00 GMT
This article describes a flexible track system model (FTSM) that represents the track structure for a typical ballasted track, taking into account the flexibility of the rails, the sleeper mass and the resilience of the pad/fastening elements, as well as the ballast support stiffness condition. The detailed track model is integrated into a commercial railway vehicle dynamics software, thus allowing for any vehicle to be simulated onto the flexible track while at the same time taking into account the detailed calculation of the non-linear wheel–rail contact interaction. As an example, the application of the FTSM to the study of hanging sleepers, with respect to the UK Railway Group Standard limits, is presented. This example shows the impact of forces because of hanging sleepers on the vehicle and on the track, and attempts at quantifying the damage made to the track components for the specific conditions simulated.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT276
- Authors
- Y Bezin, Engineering & Technology Department, Manchester Metropolitan University, Manchester, UK
- S D Iwnicki, Engineering & Technology Department, Manchester Metropolitan University, Manchester, UK
- M Cavalletti, VI-Grade, Perugia, Italy
- E de Vries, MSC.Software Limited, London, UK
- F Shahzad, MSC.Software Limited, London, UK
- G Evans, Corus Rail Technologies, Swinden Technology Centre, Moorgate, Rotherham, UK
Date: Fri, 26 Jun 2009 16:04:50 GMT
Rail corrugation is a phenomenon of great diversity but appears now to be substantially understood. This review proposes some differences in classification of the phenomenon to take account of work undertaken since a widely cited review was published by Grassie and Kalousek in 1993, it attempts to fill holes in an overall understanding of the problem, and answers questions that remained open in 1993 and several that have arisen since. All types of corrugation that have been documented to date are essentially constant-frequency phenomena. By treating the vehicle–track system in its entirety, treatments are proposed that impinge upon track and vehicle design as well as upon the wheel–rail interface where corrugation appears. There is no neat solution to rail corrugation, but it can be treated comprehensively and in many cases also prevented by using products that are already commercially available. Since the frequency of common wavelength-fixing mechanisms varies roughly in the range 50–1200 Hz, trains travelling at different speeds can produce corrugation of substantially similar wavelength by different mechanisms in different locations. Although historical data can no longer be checked, this is the most likely explanation of the belief that rail corrugation was a substantially constant-wavelength phenomenon.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT264
- Authors
Date: Fri, 26 Jun 2009 16:04:50 GMT
This article develops two relatively simple models that are combined in order to model the response of a standing person to a passing train. The first model combines potential flow theory, boundary layer theory, and autoregressive modelling in order to simulate the slipstream of a passenger train. The second moment simulates the response of a person to the wind velocities generated in the slipstream model. For the first 0.375 s the person is assumed to respond as a solid object, whereas after this time a spring–mass–damper system is used to represent the response of a person. A Monte Carlo analysis is used in order to establish the probability of a person becoming destabilized as a result of increasing train speed. Finally, a parametric analysis is undertaken and illustrates that the output of the models that represent the response of a person is sensitive to the parameter values chosen.
- Content Type Journal Article
- DOI 10.1243/09544097JRRT281
- Authors
- S C Jordan
- M Sterling
- C J Baker