Journal articles: 'Track running'

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SEI, Kenji. "All Weather Running Track." NIPPON GOMU KYOKAISHI 83, no. 5 (2010): 125–32. http://dx.doi.org/10.2324/gomu.83.125.

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Koc, Władysław. "Speed of Trains Running on Parallel Track Connections Using Curved Turnouts." Problemy Kolejnictwa - Railway Reports 64, no. 189 (December 2020): 85–95. http://dx.doi.org/10.36137/1892e.

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The issue of connecting parallel main tracks located in a circular curve by means of curved turnouts is discussed in the pa-per, focusing on determining the achievable train speed. Selected geometries are used in the analysis. The curved turnout diverging track radii and the corresponding train speeds are determined. An analytical notation is used, thereby creating greater options in specific applications. It is shown that the speed of trains running on parallel track connections depends on the type of basic turnout subjected to curving (i.e. mainly on the radius of this turnout), while the second very important factor is the value of the track cant used. In each case, the determined speed resulting from the diverging track radius is lower than the speed on the main tracks. While discussing the general principles of constructing parallel track connections in a circular arc using curved turnouts, it is pointed out that in some situations the speed of travel must be further reduced due to the need to connect the ends of the diverging tracks with a circular arc. Keywords: railway turnouts, turnout curving, speed analysis, connecting diverging tracks

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Brown, Alan S. "Running Energy." Mechanical Engineering 121, no. 06 (June 1, 1999): 58–61. http://dx.doi.org/10.1115/1.1999-jun-4.

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Composite Power Corp., Las Vegas, plans to use composites as a key material in a wind turbine a quarter-mile across that will turn on air or magnetic bearings in breezes as mild as 3 mph. Composite towers cost more than steel, however, are cheaper to transport and easier to assemble on-site, making them cost-competitive, especially in remote areas. Since composite towers have small footprints, they can share rights of way with railroad tracks. The system is designed so even if a car jumps the track and takes out up to three towers, the fiber-reinforced cable will remain intact. Beginning with inexpensive coal fuel, the proposed Montana-Wisconsin line will deliver power for an estimated 3 cents a kilowatt, compared with the 4 to 9 cents a kilowatt it costs other state utilities. The heart of the technology consists of cables made of aluminum strengthened by a composite wrapping. Although aluminum has a generous current-carrying capacity, its poor mechanical strength has curbed its role in power transmission lines.

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Worsey, Matthew T. O., Hugo G. Espinosa, Jonathan B. Shepherd, Julian Lewerenz, Florian S. M. Klodzinski, and David V. Thiel. "Features Observed Using Multiple Inertial Sensors for Running Track and Hard-Soft Sand Running: A Comparison Study." Proceedings 49, no. 1 (June 15, 2020): 12. http://dx.doi.org/10.3390/proceedings2020049012.

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Variability in the running surface can cause an athlete to alter their gait. Most literature report running on grass, a treadmill or athletics running tracks using inertial sensors. This study compares the signals obtained by 9 degrees of freedom (DOF) inertial-magnetic sensors incorporating an accelerometer (±16 g), gyroscope (±2000°/s) and magnetometer (±8 gauss). The sensors were placed on the participant’s shank, knee, lower spine and upper spine, and the participants were asked to run on three different surfaces (running track, hard sand and soft sand). The calculated player loads for a 400 m run on each surface type was very similar. The mean and standard deviation values were 577 ± 130, 581 ± 128, 568 ± 124 for soft sand, hard sand and the running track, respectively. This did not correlate with the participant’s self-assessment RPE (Rate of perceived exertion), which demonstrated running on soft sand to be significantly more challenging, yielding a mean and standard deviation of 5.3 ± 2.5 (Hard to Very Hard). Soft sand running had a decreased swing time duration but increased variability (0.44 ± 0.02 s—Swing Time, 6.5 ± 1.1%—CV), hard sand running had the longest swing and intermediate variability duration (0.46 ± 0.02 s—Swing Time, 3.30 ± 2.58 %—CV) and running track running had the medium swing time but lowest variability (0.45 ± 0.02 s, 2.7 ± 0.9%—CV). Gait dominance was not consistent across the surfaces for each participant and remained below a ratio of 0.4. These results provide an insight into how athletes modify their gait mechanics to accommodate different running surfaces.

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Vu, Linh, Dong-Doo Jang, and Yun-Suk Kang. "Assessment of Structural Dynamic Response and Vehicle-Track Interaction of Precast Slab Track Systems." Applied Sciences 11, no. 8 (April 15, 2021): 3558. http://dx.doi.org/10.3390/app11083558.

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Recently, precast slab tracks have been used widely in railway applications, especially in conventional urban railway lines. These types of tracks are rapidly constructed and limit interruptions to train operation. However, the problems of dynamic stability when the trains run on the discontinuous type of tracks must be seriously considered. This paper focuses on analyzing the train-track interaction in two types of tracks under the dynamic load by using the numerical analysis program (APATSI) to evaluate the structural response as well as the running safety to precisely understand the load transfer efficiency of precast slab track systems.

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Panascì, Marco, Romuald Lepers, Antonio La Torre, Matteo Bonato, and Hervè Assadi. "Physiological responses during intermittent running exercise differ between outdoor and treadmill running." Applied Physiology, Nutrition, and Metabolism 42, no. 9 (September 2017): 973–77. http://dx.doi.org/10.1139/apnm-2017-0132.

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The aim of this study was to compare the physiological responses during 15 min of intermittent running consisting of 30 s of high-intensity running exercise at maximal aerobic velocity (MAV) interspersed with 30 s of passive recovery (30–30) performed outdoor versus on a motorized treadmill. Fifteen collegiate physically active males (age, 22 ± 1 years old; body mass, 66 ± 7 kg; stature, 176 ± 06 cm; weekly training volume, 5 ± 2 h·week−1), performed the Fitness Intermittent Test 45–15 to determine maximal oxygen uptake (V̇O2max) and MAV and then completed in random order 3 different training sessions consisting of a 30-s run/30-s rest on an outdoor athletic track (30–30 Track) at MAV; a 30-s run/30-s rest on a treadmill (30–30 Treadmill) at MAV; a 30-s run/30-s rest at MAV+15% (30–30 + 15% MAV Treadmill). Oxygen uptake (V̇O2), time above 90%V̇O2max (t90%V̇O2max), and rating of perceived exertion (RPE) were measured during each training session. We observed a statistical significant underestimation of V̇O2 (53.1 ± 5.4 mL·kg−1·min−1 vs 49.8 ± 6.7 mL·kg−1·min−1, –6.3%, P = 0.012), t90%V̇O2max (8.6% ± 11.5% vs 38.7% ± 32.5%, –77.8%, P = 0.008), RPE (11.4 ± 1.4 vs 16.5 ± 1.7, –31%, P < 0.0001) during the 30–30 Treadmill compared with the same training session performed on track. No statistical differences between 30–30 +15 % MAV Treadmill and 30–30 Track were observed. The present study demonstrates that a 15% increase in running velocity during a high-intensity intermittent treadmill training session is the optimal solution to reach the same physiological responses than an outdoor training session.

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Picerno, Pietro, and Johnny Padulo. "Acute kinematic adaptations to running on a centrifugal track: A pilot study." Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology 232, no. 3 (January 1, 2018): 275–81. http://dx.doi.org/10.1177/1754337117749515.

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The centrifugal track, a basin-shaped track characterised by a platform with a parabolic section, exploits the centripetal acceleration to increase the bodyweight of the athlete during the foot contact phase of running. Because this overload is produced by an inertial force that is equally distributed to the infinitesimal point masses of the body, no postural changes are expected with respect to level running. This pilot study aimed to compare some selected key kinematic quantities of running on the centrifugal track with respect to level running. A video-based three-dimensional (3D) motion analysis was performed on five sprinters and used to compute spatio-temporal variables, frontal and sagittal trunk kinematics and knee sagittal kinematics at footstrike, midstance and foot-off over two consecutive steps at similar speeds. No significant changes were found in spatio-temporal variables and knee kinematics between the right and the left leg during running on the centrifugal track. Neither step length nor step duration was found statistically different between the two running typologies. Trunk flexion was not altered during the stance phase of running on the centrifugal track. Knee angle at footstrike was found similar to level running. A slightly larger but statistically significant knee flexion at midstance and knee extension at foot-off were found with respect to flat-track running, but these findings appear more beneficial for strength training rather than detrimental for the running technique. The centrifugal track was found to be a viable alternative to the common resisted sprint training techniques as the training effect is produced without localised overloads on the musculoskeletal system and detrimental postural changes.

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Kawamoto, Ryuji, Yusuke Ishige, Koji Watarai, and Senshi Fukashiro. "Influence of Curve Sharpness on Torsional Loading of the Tibia in Running." Journal of Applied Biomechanics 18, no. 3 (August 2002): 218–30. http://dx.doi.org/10.1123/jab.18.3.218.

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The purpose of this study was to test quantitatively the hypothesis that, as runners run along a more sharply curved track, greater torsional moments act on their tibiae. Six male participants were asked to run along a straight track and along counterclockwise curved tracks with turn radii of 15 m (gentle) and 5 m (sharp) at 3.5 m s–1. Data were collected using two high-speed cameras and force platforms. Each participant’s left (corresponding to the inside of the curves) foot and tibia were modeled as a system of coupled rigid bodies. For analysis, net axial moments acting on both ends of the tibia were calculated using free-body analysis. The torsional moment acting on the tibia was determined from the quasi-equilibrium balance of the tibial axial moments based on the assumption that the rate of change of the angular momentum about the tibial axis was negligible. The results showed that the torsional moments, which were in the direction of external rotational loading of the proximal tibiae, increased as the track curvature became sharper. Furthermore, the mean value of the maximum torsional moments, while running on a sharply curved track (28.5 Nm), was significantly higher than the values obtained while running on a straight track (11.0 Nm, p < .01) and on a gently curved track (12.2 Nm, p < .01). In conclusion, the present study has quantitatively confirmed that as runners run along a more sharply curved track, greater torsional moments act on their tibiae. The findings imply that athletes prone to tibial running injuries such as stress fractures should avoid repetitive running on sharply curved paths.

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Ford, R. A. J. "Track and Ground Vibrations from Trains Running on Conventional Ballasted Track." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 206, no. 2 (July 1992): 117–26. http://dx.doi.org/10.1243/pime_proc_1992_206_225_02.

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This theoretical analysis predicts how spectra of track and ground vibrations from passing trains depend upon axle spacings in vehicles and sleeper spacings in track. At any measuring point on the surface of the ground, vibrations caused by trains running on conventional ballasted track are the combined effect of vibration waves propagating from every sleeper. The character of these vibrations is initially determined by the character of the vibration input that the train applies to each sleeper, but this is substantially modified by what happens as the resulting vibration waves propagate to the measuring point and superpose there. Propagation and superposition strongly modulate the input spectrum from trains, emphasizing vibrations at some frequencies in the measured response while minimizing vibrations at others. The shape of the final predicted spectrum depends upon the interrelationship of sleeper spacing and axle spacings, so it may be possible through careful choice of these dimensions to reduce the unwanted effects of train-induced vibrations—for example by minimizing excitation at known resonant frequencies of sensitive line-side structures. The predictions of the theory now await checking by experiment.

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Fries, R. H., and C. G. Da´vila. "Wheel Wear Predictions for Tangent Track Running." Journal of Dynamic Systems, Measurement, and Control 109, no. 4 (December 1, 1987): 397–403. http://dx.doi.org/10.1115/1.3143873.

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Wear of wheels and rails is a problem of substantial magnitude for railways throughout the world. Efforts to control wear by using new wheels profiled to match worn wheels have met with a measure of success. Purely empirical approaches to this problem require years of effort before results can be assessed. This paper describes a computational method for predicting worn profiles. The method is applied here to freight cars running on tangent track, and it includes the capability to handle both stable and hunting running. The method has been evaluated with four different wear models, and it was found that the predicted worn wheel profiles are relatively insensitive to the selection of wear model. Results include predictions from AAR and CNA wheels running on new rail, and from a simulated unit-train operation.

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Picerno, Pietro. "Dynamics of running on a centrifugal track." Sports Engineering 20, no. 3 (March 14, 2017): 239–42. http://dx.doi.org/10.1007/s12283-017-0231-4.

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Bigelow, Erin M. R., Niell G. Elvin, Alex A. Elvin, and Steven P. Arnoczky. "Peak Impact Accelerations during Track and Treadmill Running." Journal of Applied Biomechanics 29, no. 5 (October 2013): 639–44. http://dx.doi.org/10.1123/jab.29.5.639.

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To determine whether peak vertical and horizontal impact accelerations were different while running on a track or on a treadmill, 12 healthy subjects (average age 32.8 ± 9.8 y), were fitted with a novel, wireless accelerometer capable of recording triaxial acceleration over time. The accelerometer was attached to a custom-made acrylic plate and secured at the level of the L5 vertebra via a tight fitting triathlon belt. Each subject ran 4 miles on a synthetic, indoor track at a self-selected pace and accelerations were recorded on three perpendicular axes. Seven days later, the subjects ran 4 miles on a treadmill set at the individual runner’s average pace on the track and the peak vertical and horizontal impact magnitudes between the track and treadmill were compared. There was no difference (P= .52) in the average peak vertical impact accelerations between the track and treadmill over the 4 mile run. However, peak horizontal impact accelerations were greater (P= .0012) on the track when compared with the treadmill. This study demonstrated the feasibility for long-term impact accelerations monitoring using a novel wireless accelerometer.

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Ham, Young Sam, Jai Sung Hong, and Taek Yul Oh. "A Study on the Evaluation Methods of Running Safety for Railway Vehicle." Key Engineering Materials 321-323 (October 2006): 1499–502. http://dx.doi.org/10.4028/www.scientific.net/kem.321-323.1499.

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The important factor to evaluate the running safety of a railway vehicle would be the interaction force between wheel and rail(derailment coefficient), for which is one of important factors to check the running safety of a railway vehicle that may cause a tragic accident. Especially, a newly developed vehicle that first runs commercially requires necessarily the measurement and evaluation of derailment coefficient for securing the safety of a vehicle while measuring the derailment coefficient in view of securing running safety could be the more important factor than any other factors. In the meanwhile, it should be also measured the interaction force between wheel and rail in view of track maintenance as well as running safety because increased weight of a vehicle while it is running over a railway may cause damages or destruction on track components such as rails, sleepers and etc consisted of track and any rapid distortion of track. For the reason, the study was intended to evaluate the curving performance and the running safety from the analyses of dynamic running properties, manufacturing wheel axes to measure the working operation of wheels/rail, static load test, derailment coefficient calculated by running test on main track, ratio of wheel unloading, lateral force tolerance of the vehicle that is newly manufactured and commercially running on Gwangju Urban Railway and describe the results.

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Jin, Zhibin, Ligang Yuan, and Shiling Pei. "Efficient evaluation of bridge deformation for running safety of railway vehicles using simplified models." Advances in Structural Engineering 23, no. 3 (September 13, 2019): 454–67. http://dx.doi.org/10.1177/1369433219875304.

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The running safety of high-speed trains over bridges is a great concern in bridge design. Typically, the running safety of vehicles is evaluated by vehicle–track simulations that are computationally expensive and unfamiliar to bridge designers. This study investigates simplified vehicle–track models for assessing the running safety of vehicles on deformed bridges. Four types of simplified vehicle models along with four types of simplified wheel–track models are investigated. The predicted wheel–rail forces are compared with those simulated by the detailed vehicle–track program. In these simulations, typical bridge deformations are taken as excitations to the dynamic system. It is found that omitting the rail vibration leads to large wheel–rail response errors. The wheel–rail constraint model gives similar wheel–rail responses to those obtained by the Hertz contact model. A vehicle–track model with five degrees-of-freedom is adequate for assessing wheel–rail forces. Furthermore, an analytical solution to the wheel–rail forces running over an angular rotation was obtained. These simplified vehicle–track models provide an efficient way to assess the running safety of vehicles on deformed bridges when using probabilistic or optimal analyses that require a large number of simulations.

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Lou, Ping, Kailun Gong, Chen Zhao, Qingyuan Xu, and Robert K. Luo. "Dynamic Responses of Vehicle-CRTS III Slab Track System and Vehicle Running Safety Subjected to Uniform Seismic Excitation." Shock and Vibration 2019 (July 21, 2019): 1–12. http://dx.doi.org/10.1155/2019/5308209.

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The dynamic model for the vehicle-CRTS III slab track system is established subjected to uniform seismic excitation, and the calculation program with MATLAB is compiled and verified. The influences of track parameters, seismic intensity, and running speed of the vehicle on the dynamic responses of the system and the vehicle running safety are analyzed. The results show that (1) the track parameters have certain influence on the dynamic responses of the system, and the seismic intensity and the running speed of the vehicle have important influence on the vehicle running safety; (2) the derailment coefficient is highly sensitive to seismic intensity, and the wheel load reduction rate is also highly sensitive to the running speed of the vehicle.

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Wee, Veronika Myran, Erna Von Heimburg, and Roland Van den Tillaar. "Comparison of perceptual and physiological variables of running on a track, motorized treadmill, and non-motorized curved treadmill at increasing velocity." Acta Kinesiologiae Universitatis Tartuensis 22 (December 19, 2016): 20. http://dx.doi.org/10.12697/akut.2016.22.02.

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The aim of this study was to compare perceptual and physiological variables between running on three different modalities — an indoor athletics track, a motorized treadmill, and a non-motorized curved treadmill — for 1000 m at three different velocities. Ten male athletes (age 24±3 years, body mass 69.8±6.91 kg, height 1.80±0.06 m, VO2peak 69.0±6.70 ml/kg/ min) conducted three 1000 m laps at increasing velocity on three different running modalities. The athletes had a 3-minute recovery between each lap, where the rate of perceived exertion (RPE) was registered and the blood lactate concentration and heart rate were measured. Oxygen uptake was measured using a portable metabolic analyser. The physiological (oxygen uptake, heart rate, and blood lactate concentration) and perceptual (RPE) variables were higher when running on a non-motorized curved treadmill compared with running on the track or a motorized treadmill. No differences were found between running on a motorized treadmill and the track except for the RPE, which was lower when running on the track compared with the motorized treadmill. Running on a non-motorized curved treadmill at three different velocities results in a higher oxygen uptake (37%) and heart rate (22%) and is subjectively much harder than running on a track or a motorized treadmill at the same velocities. The difference is around 4 km/h when comparing the physiological and perceptual responses. Thus, when performing training sessions on a non-motorized curved treadmill, subjects should subtract 4 km/h from their regular pace on a track or motorized treadmill to get the same response considering oxygen uptake, heart rate, RPE and blood lactate concentration.

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Tucker, Ross, Vincent O. Onywera, and Jordan Santos-Concejero. "Analysis of the Kenyan Distance-Running Phenomenon." International Journal of Sports Physiology and Performance 10, no. 3 (April 2015): 285–91. http://dx.doi.org/10.1123/ijspp.2014-0247.

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Purpose:To investigate the ethnicity of Kenya’s most successful international runners, tracking their evolution over the period of their international emergence and current dominance.Methods:The authors analyzed male track distance events from 800m upwards from all the major global athletics championships from 1964 to 2013, and the annual Top-25 world marathon performances since 1990.Results:The percentage of top-25 marathon performances and medals won by Kenyan and Kalenjin runners have increased over time with Nandi subtribe outperforming the rest of the world outside Africa (r > .70, large effect). However, Europe, North America, Oceania, Asia, and South America decreased over time in top marathon performances and track medals won (r > .70, large effect). The tribe and subtribe distribution was different in the marathon than in the track: Maasais were more likely to feature in medals won in shorter track events than in the top 25 of the world marathon rankings (risk ratio [RR] = 9.67, very large effect). This was also the case for Marakwets (RR = 6.44, very large effect) and Pokots (RR = 4.83, large effect). On the other hand, Keiyos, Kikuyus, Kipsigis, Sabaots, and Tugens were more likely to succeed in the marathon than in shorter track events (RR > 2.0, moderate effect).Conclusion:These data emphasize that the previously documented emergence of African distance runners is primarily a Kenyan phenomenon, driven by the Kalenjin tribe and in particular the Nandi subtribe. This supports the complex interaction between genotype, phenotype, and socioeconomic factors driving the remarkable dominance of Kenyan distance runners.

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Behncke, Horst. "Small Effects in Running." Journal of Applied Biomechanics 10, no. 3 (August 1994): 270–90. http://dx.doi.org/10.1123/jab.10.3.270.

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The influence of altitude, wind, and track curvature is studied on the basis of a simple biomechanical model. The results are compared with some data from the Olympic Games in Tokyo, Munich, and Mexico City. The influence of these factors is found to be considerably larger than the current precision in the measurement of records.

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Seo, Sungil, Hyung-Suk Mun, Myung-Eun Suk, and Ji-Ho Moon. "Development of a bogie for running on a track having a steep gradient and sharp curves." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 232, no. 4 (May 16, 2017): 1121–34. http://dx.doi.org/10.1177/0954409717709108.

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In this study, core technologies are developed for a bogie system to enable the bogie to run on a track that has a steep gradient and sharp curves. The bogie is designed to run on a minimum curve radius of 10 m by developing independently rotating wheels and axles. It is also designed to run on a maximum gradient of 180‰ with reduced noise by developing an elastic pinion. The traction motor power required for a steep gradient is calculated and reflected in the design of the traction system. In addition, a band braking system is developed to improve the braking force while running on a steep gradient track. The developed main parts are tested to evaluate their performance and are subsequently applied to the bogie systems designed to run on a steep gradient and sharp curve tracks. The maximum load on the bogie frame is reassessed by considering the running conditions on a track that has a steep gradient and sharp curves. The safety of the bogie frame is verified through a loading test. Finally, the developed bogie system with the incorporated parts and core technologies undergoes a running test on a roller rig for evaluating its performance.

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Ketting, Michael, and Christoph Pietzsch. "Strength-optimal running surface contour for track links." Journal of Terramechanics 34, no. 2 (March 1997): 109–26. http://dx.doi.org/10.1016/s0022-4898(97)00020-7.

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Costa, Ricardo J. S., Beat Knechtle, Mark Tarnopolsky, and Martin D. Hoffman. "Nutrition for Ultramarathon Running: Trail, Track, and Road." International Journal of Sport Nutrition and Exercise Metabolism 29, no. 2 (March 1, 2019): 130–40. http://dx.doi.org/10.1123/ijsnem.2018-0255.

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Ultramarathon running events and participation numbers have increased progressively over the past three decades. Besides the exertion of prolonged running with or without a loaded pack, such events are often associated with challenging topography, environmental conditions, acute transient lifestyle discomforts, and/or event-related health complications. These factors create a scenario for greater nutritional needs, while predisposing ultramarathon runners to multiple nutritional intake barriers. The current review aims to explore the physiological and nutritional demands of ultramarathon running and provide general guidance on nutritional requirements for ultramarathon training and competition, including aspects of race nutrition logistics. Research outcomes suggest that daily dietary carbohydrates (up to 12 g·kg−1·day−1) and multiple-transportable carbohydrate intake (∼90 g·hr−1 for running distances ≥3 hr) during exercise support endurance training adaptations and enhance real-time endurance performance. Whether these intake rates are tolerable during ultramarathon competition is questionable from a practical and gastrointestinal perspective. Dietary protocols, such as glycogen manipulation or low-carbohydrate high-fat diets, are currently popular among ultramarathon runners. Despite the latter dietary manipulation showing increased total fat oxidation rates during submaximal exercise, the role in enhancing ultramarathon running performance is currently not supported. Ultramarathon runners may develop varying degrees of both hypohydration and hyperhydration (with accompanying exercise-associated hyponatremia), dependent on event duration, and environmental conditions. To avoid these two extremes, euhydration can generally be maintained through “drinking to thirst.” A well practiced and individualized nutrition strategy is required to optimize training and competition performance in ultramarathon running events, whether they are single stage or multistage.

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Belli, A., H. Kyröläinen, and P. V. Komi. "MECHANICAL EFFICIENCY COMPARISON BETWEEN TREADMILL AND TRACK RUNNING." Medicine & Science in Sports & Exercise 27, Supplement (May 1995): S162. http://dx.doi.org/10.1249/00005768-199505001-00914.

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Aftalion, Amandine, and Pierre Martinon. "Optimizing running a race on a curved track." PLOS ONE 14, no. 9 (September 5, 2019): e0221572. http://dx.doi.org/10.1371/journal.pone.0221572.

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Huang, Jingyu, Xiong Zhou, Liwei Shang, Zhewei Wu, Weinan Xu, and Dongzhou Wang. "Influence analysis of track irregularity on running comfort of Maglev train." Transportation Systems and Technology 4, no. 2 (September 13, 2018): 129–40. http://dx.doi.org/10.17816/transsyst201842129-140.

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Background: In this article, the TR08 car of the Shanghai Magnetic Train Demonstration Line was prototyped and a multi-body dynamics simulation model was established. And based on the low-interference track irregularity power spectrum in Germany, track irregularity data was obtained. Used dynamic simulation software, completed the dynamic simulation analysis of the vehicle-rail model controlled by the proportion-integral-derivative control system PID parameters. It can be concluded that the vibration of trains passing through irregular tracks at different speeds, and evaluated its comfort. The optimal solution for the control of the PID parameters of the train also has been derived. Aim: Evaluation of operational comfort and suspension gap control effect of Shanghai Maglev Train Demonstration Line by simulation analysis. Materials and methods of the studies: Simulation analysis. Results: The vibration acceleration and suspension gap of Shanghai Maglev Train Demonstration Line has been obtained. Conclusion: By adjusting the parameters of PID control system, the vibration acceleration of train can be reduced and the ride comfort can be improved.

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Qiao, Rui Jun, Xiao Ning Zhu, and Wei Yan. "Optimized Utilization of Station Arrival and Departure Tracks for Passenger Dedicated Lines." Advanced Materials Research 468-471 (February 2012): 2450–54. http://dx.doi.org/10.4028/www.scientific.net/amr.468-471.2450.

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For running trains according to timetable, it is very important to arrange appropriate arrival and departure tracks to trains transacted by passenger dedicated line station. Builds optimized model of arrival and departure track utilization, the optimization objective is maximizing the sum of weights of trains using tracks, and having the most balanced utilization schedule. For constraints, it is different from existing railway station that the two turnaround trains share the same train-set must be arranged to the same arrival and departure track, and this paper considers the constraint seriously. Taking Beijing South Railway Station inter-city yard as an instance, use the method put forward in this paper to calculate the arrival and departure track utilization schedule. Compared with existing schedule, the result calculated makes the arrival and departure track utilization more balanced.

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Waddington, G., T. Dickson, S. Trathen, and R. Adams. "Walking for fitness: is it enough to maintain both heart and bone health?" Australian Journal of Primary Health 17, no. 1 (2011): 86. http://dx.doi.org/10.1071/py10035.

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Exercising at levels of whole body accelerations exceeding 3.6 g has been shown to have positive effects on cardiovascular fitness, bone density and balance. This pilot research project evaluated the whole body accelerations and cardiovascular challenge provided by selected walks in the Canberra region of Australia to determine if walks could be ranked according to potential level of impact on both cardiovascular fitness and bone health. Nine participants, who described themselves as walking at least 3 km, three times per week, wore a data logging device recording heart rate, acceleration and GPS position while walking three outdoor tracks: (1) the running track of an athletics stadium; (2) on a hill climb path through bushland; and (3) on a route through suburban streets. There was a significant difference (P < 0.05) for heart rate, distribution of whole body accelerations and average walking speed between track 2 and tracks 1 and 3. There was a significant difference for heart rate, distribution of whole body accelerations and average walking speed between the walks. The running track and the suburban walk provide a moderate exercise challenge, with the hill climb walk providing progressively greater vertical height challenge, resulting in an increased cardiovascular exercise challenge. No participant effectively exceeded the threshold for achieving a positive impact on bone density (100 or more accelerations/day >3.6 g) on track 1, and only two of the nine participants intermittently achieved this threshold on tracks 2 and 3.

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Cai, Yi Chang, Hao Pu, Wei Li, Jian Li, Xi An Long, and Hai Feng Zhao. "Study and Application of High-Speed Railway Real-Time Dynamic Response Based on Running Simulation." Advanced Materials Research 779-780 (September 2013): 695–99. http://dx.doi.org/10.4028/www.scientific.net/amr.779-780.695.

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In order that the vehicle-track dynamic simulation can reflect the actual operation better, the running simulation theory was introduced into the analysis process of the high-speed railway dynamic response. Firstly, the data (including time, mileage, velocity, acceleration, etc.) of train running simulation was worked out by traction calculation. Secondly, according to the structure feature of high-speed railways vehicle and track, the vehicle-track coupled dynamic model was built. Non-linear Hertz theory was used for modeling the wheel-rail contact. Then the wheel-track creep force was obtained by using Kalker's creep theory and Shen's non-linear theory. Meanwhile, various track spectrums were simulated. Furthermore, the running simulation data as the original data were used to work out the real-time dynamic response indices in the dynamic calculation process. Thirdly, the indices would be applied to the alignment comfort evaluation. Finally, the system was developed out and the rationality and practicability of the method were verified through an example.

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Calimeri, Francesco, Giovambattista Ianni, Thomas Krennwallner, and Francesco Ricca. "The Answer Set Programming Competition." AI Magazine 33, no. 4 (December 21, 2012): 114. http://dx.doi.org/10.1609/aimag.v33i4.2448.

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The Answer Set Programming (ASP) Competition is a biannual event for evaluating declarative knowledge representation systems on hard and demanding AI problems. The competition consists of two main tracks: the ASP system track and the model and solve track. The traditional system track compares dedicated answer set solvers on ASP benchmarks, while the model and solve track invites any researcher and developer of declarative knowledge representation systems to participate in an open challenge for solving sophisticated AI problems with their tools of choice. This article provides an overview of the ASP competition series, reviews its origins and history, giving insights on organizing and running such an elaborate event, and briefly discusses about the lessons learned so far.

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Yue, Guo-dong, Zheng Xu, Liding Wang, Chong Liu, and Tongqun Ren. "WSN-Based Vibration Characteristic Research for Various Railway Track Structures for Pattern Classification." International Journal of Pattern Recognition and Artificial Intelligence 30, no. 10 (November 23, 2016): 1650020. http://dx.doi.org/10.1142/s0218001416500208.

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To effectively study vibration characteristics of tracks under different track structures, wavelet transforms of the vibration data are used for pattern classification of vibration feature. First, acceleration data of the track are collected with running speed of 150[Formula: see text]km/h at 26 positions respectively on a slab tangent track, ballast tangent track and ballast curve track by a wireless sensor network (WSN). Then they are analyzed using the power spectral densities (PSDs) and wavelet-based energy spectrum analysis. The paper elaborates on the reasons for the differences of vibration energy and excitation frequencies due to the mechanism of different frequency bands and the corresponding track structures. Based on these, the instantaneous frequencies, vibration energies and durations in the low, medium, and high frequency bands are selected as the features for three track structures. A function curve representing the features is proposed to detect the abnormal track structure by a correlation analysis. Finally, the proposed method of pattern classification has been validated by experimental testings.

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Ribeiro, Heitor Siqueira, Hugo de Luca Corrêa, Lívia Kelly Barbosa Lima, Maria Barroso Costa Filha, Severino Leão Albuquerque Neto, Edilberto Santos Barros, and Aparecido Pimentel Ferreira. "Agreement and reproducibility of field and laboratory tests in the prediction of running speed in a 10-km race in amateur runners." Kinesiology 52, no. 2 (2020): 299–307. http://dx.doi.org/10.26582/k.52.2.16.

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Knowing running speed, particularly by means of easy-to-apply tests and low cost, is important for the definition of the race strategy and the most appropriate training throughout the preparation period. The aim was to compare the agreement and reproducibility of critical velocity (CV), anaerobic threshold (AT), and the simulated time trial on the track for the determination of the running speed in a 10-km race in amateur runners. A cross-sectional study was conducted with 34 runners of both genders aged 42.4±11.0 years. We measured their CV, assessed their body composition and AT. Participants performed also a simulated time trial on a 10-km running track and an official 10-km race. The delta of the comparisons and the standard error of estimate between the running velocities determined by the CV, AT, and the simulated time trial on the track ranged from 0.55 to -0.79 km/h and 0.14 to 0.59 km/h, respectively. Furthermore, CV and AT were compared to the 10-km running speed. Good agreement and reproducibility were observed between the velocities determined by the CV, AT, and the simulated time trial on the track with the real-time of a 10-km official race.

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Vercoutere, C., and P. Van Den Haute. "Post-Palaeozoic cooling and uplift of the Brabant Massif as revealed by apatite fission track analysis." Geological Magazine 130, no. 5 (September 1993): 639–46. http://dx.doi.org/10.1017/s001675680002094x.

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AbstractA fission track study has been carried out on apatite from the igneous rock belt running along the southern border of the Brabant Massif. The study includes age determinations and a length analysis of both surface tracks and confined tracks. Apatite fission track ages vary between 146 Ma and 209 Ma. Confined track length distributions and the projected length age spectra indicate that the rocks cooled relatively rapidly from above 100 °C to ambient temperatures. The fission track ages therefore date a cooling phase of the Brabant Massif which is interpreted as reflecting an important uplift during the major part of the Jurassic, related to the Cimmerian tectonism which affected the North Sea basin and adjacent areas. Two apatite samples from the southerly Dinant Basin yield fission track ages around 200 Ma, similar to the oldest ages observed in the Brabant Massif, and with comparable track length characteristics. This indicates that the uplift was not limited to the Brabant region but also affected the Hercynian basement to the south.

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Lu, Tian Yu, Zu Jun Yu, and Hong Mei Shi. "Vibration Analysis of Vehicle-Rail System under the Condition of Track Stiffness Irregularity." Applied Mechanics and Materials 368-370 (August 2013): 1431–37. http://dx.doi.org/10.4028/www.scientific.net/amm.368-370.1431.

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The interaction of track structure and high-speed train has greater impact on safe and steady running of the trains. This paper obtained acceleration and frequency spectrum of the train's running vibration in the case of sleeper’s spacing and continuous failure， and continuous and spacing loose tie by establishing the vertical model of vehicle-track coupling system, and analyzed the sleeper failure and loose tie which has a greater impact on the 40-80 Hz vibration frequency of the train, which provided a basis for track maintenance.

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Thompson, Dixie L., and Keith A. West. "Ratings of Perceived Exertion to Determine Intensity During Outdoor Running." Canadian Journal of Applied Physiology 23, no. 1 (February 1, 1998): 56–65. http://dx.doi.org/10.1139/h98-003.

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A paucity of data exists related to the usefulness of Ratings of Perceived Exertion (RPE) to set exercise intensity in non-laboratory settings. The purpose of this study was to determine if RPE could be used on an outdoor track to generate blood lactate and heart rate (HR) responses similar to those obtained on a treadmill (tm) run. Nine experienced runners (6 males, 3 females; [Formula: see text]) completed a horizontal, incremental tm test. HR, RPE, and lactate were measured for each stage. Subsequently, subjects ran for 30 min on an outdoor track at the RPE corresponding with 2.5 mM lactate during the tm run. Repeated measures ANOVA compared lactate and HR values at 2.5 mM lactate on the tm run and values obtained during the track run. Lactate during the track run was significantly higher (p < .05) than 2.5 mM throughout the 30 min (6.9 ± 2.9, 63 ± 2.9, and 5.8 ± 3.0 mM at 10, 20, and 30 min, respectively). HR at 2.5 mM lactate during the tm run (173 ± 6.1 bpm) was significantly lower (p < .05) than at min 10 and 20 of the track run (182.6 ± 9.3 and 182.9 ± 8.0 bpm, respectively) but not different from min 30 (181.3 ± 10.6 bpm). In summary, it is difficult to generate specific physiological responses using RPE. Key words: RPE, Borg Scale, exercise, lactate, training

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Shi, Hong Mei, and Zu Jun Yu. "Dynamic Responses Analysis of Vehicle and Track Based on Different Train Speed." Advanced Materials Research 706-708 (June 2013): 1314–18. http://dx.doi.org/10.4028/www.scientific.net/amr.706-708.1314.

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With the rapid development of high-speed railway, dynamic interaction between vehicles and track is correspondingly strengthened. Therefore, dynamic responses analysis of the high-speed vehicles and track become more and more important to the train operation safety, riding comfort as well as the maintenance of railway infrastructure. In this paper, vehicle and track vibration equations are separately established based on the vehicle track vertical coupling model. Taking the CRH vehicle running on the existing line as an example, the random vibration responses of the vehicle and track under different running speed are analyzed in time domain through numerical integral method and MATLAB program. According to the results, the velocity of train has more influence on the vibration property of rail and wheelsets than bogie and carbody.

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Parakhnenko, Inna, Sergey Akkerman, Andrey Romanov, and Oksana Shalamova. "Influence of change in frictional condition of track rail surfaces on interaction forces in the “wheel/rail” contact." E3S Web of Conferences 296 (2021): 02005. http://dx.doi.org/10.1051/e3sconf/202129602005.

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Determination of frictional condition of the running surface and side surface of the top of rail (lubrication) that ensures the best interaction of the rolling stock wheels and the rail, reduces the force action and thus ensures the track stability and reduced side wear of rails in the curved tracks is relevant for all the rail net.The objective of research is to determine the influence of frictional condition of the track rail surfaces on the interaction forces in the “wheel/rail” contact with various motion parameters (speed, radius).The theoretical and experimental methods were used in the research. The theoretical methods include multioptional computer modelling of axial and lateral forces that appear in the curved tracks during the freight train movement in the software package “Universal Mechanism”. The modelling results were processed with the use of correlation and regression analysis. The experimental methods include full-scale measurements in the existing track and results processing.According to the research results, the theoretical algorithms for assessment of influence of the running surface lubrication on the forces. The option of frictional condition of the wheel and rail interaction surfaces has been established to ensure reduction in the operating expenses for surfacing and rail replacement, energy costs for haulage of freight train.

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Bikov, Andrey, and Kristina Chelyadinova. "THE DIGITAL PROJECT OF THE TRACK AND ELECTRONIC MAPS FOR THE CONSTRUCTION AND REPAIR OF THE RAILWAY." Interexpo GEO-Siberia 1, no. 1 (2019): 92–98. http://dx.doi.org/10.33764/2618-981x-2019-1-1-92-98.

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Development of technology based on electronic maps and GNSS informational support of railways is one of the directions for the development of digital railways. As part of the implementa-tion of this direction, a software complex for maintenance of repairs and construction of railway tracks was developed based on the digital project of the track. This complex allows solving the tasks of preparing a working draft of repair and construction of a railway track, preparing completed doc-umentation, positioning on the ground with a digital model displayed on the track, also functions of linear referencing are available when running track machines, data visualization at the stage of creat-ing a digital track project. In addition to using the developed software (NavDMR) for solving engi-neering problems of railway track construction and repair, it is possible to fully use it as part of the current operation of the railway infrastructure.

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Wang, Li Hua, Guang Wei Liu, An Ning Huang, and Ya Yu Huang. "Research on the Lateral Vibration Characteristic of the Bogie in Dynamic Track Stabilizer with Track Irregularity Excitation." Applied Mechanics and Materials 120 (October 2011): 325–28. http://dx.doi.org/10.4028/www.scientific.net/amm.120.325.

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Bogie is one of the major critical components of the dynamic track stabilizer, and its vibration characteristics will affect the dynamic characteristics of the dynamic track stabilizer directly. It is very important to improve the running safety by analyzing the lateral vibration characteristics of the bogie. The time domain loads of the track irregularities were gained based on the U.S. spectral density of the track irregularities using the method of numerical simulate. Then the lateral vibration characteristics of the dynamic track stabilizer bogie under the excitation of the track irregularities were analyzed on the bases of the ANSYS/LS-DYNA. The results of numerical simulation and the associated experiment are basically consistent, and the analysis results can provide foundation for research on the running stationarity and safety of the dynamic track stabilizer. This research method also can provide a new effective method for further researching on the dynamic characteristics of the bogie and the dynamic track stabilizer.

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Girard, Olivier, Gregoire Millet, and Jean-Paul Micallef. "Mechanical Alterations during 800-m Self-Paced Track Running." International Journal of Sports Medicine 38, no. 04 (March 1, 2017): 314–21. http://dx.doi.org/10.1055/s-0042-121262.

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Weyand, P., K. Curcton, D. Conley, and M. Sloniger. "586 PERCENTAGE ANAEROBIC ENERGY UTILIZED DURING TRACK RUNNING EVENTS." Medicine & Science in Sports & Exercise 25, Supplement (May 1993): S105. http://dx.doi.org/10.1249/00005768-199305001-00588.

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Jones, Gareth R., Ian J. Newhouse, Jennifer M. Jakobi, Norm Lavoie, and Robert Thayer. "The Incidence of Hematuria in Middle Distance Track Running." Canadian Journal of Applied Physiology 26, no. 4 (August 1, 2001): 336–49. http://dx.doi.org/10.1139/h01-021.

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The purpose of this study was to establish if middle distance track athletes experience hematuria during their competitive season interval workouts and, if so, what type of workout based on intensity and distance was most associated with hematuria. During a 4-week observational period, athletes (n = 10) underwent reagent strip urinalysis before and after their twice weekly interval sessions. Positive samples for hematuria were analyzed microscopically to accurately determine red blood cell (RBC) loss. Seventy-one individual interval workouts were observed, of which 32 cases of hematuria were reported. Nine cases of hematuria exhibited > 100 RBC per High Power Field (Hpf). Furthermore, 90% of the athletes experienced post-workout hematuria at least once. The highest incidence of hematuria was observed after workouts run at 110% of [Formula: see text] over short (600-1,500 m) to moderate (1,501-3,000 m) distances. All post-exercise cases of hematuria resolved within 2 hr of recovery. Key words: hematuria, running, training, urinalysis

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You, Wonhee, Hyukbin Kwon, Joonhyuk Park, and Yujeong Shin. "Effect of wind gusts on the dynamics of railway vehicles running on a curved track." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 232, no. 4 (June 13, 2017): 1103–20. http://dx.doi.org/10.1177/0954409717708924.

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Due to global warming, there is an increasing number of wind gusts that affect the stability of railway vehicles. A railway vehicle running on a curved track during a wind gust is subjected to multiple forces simultaneously, which include the centrifugal force and forces exerted by the wind gust and cant, and they significantly affect the vehicle’s dynamic characteristics as well as its safety. The forces increase the vibration of carbodies and the risk of derailment and overturning of cars; the effect is worse on irregular tracks. In order to review the phenomenon in detail, a 1/20 scale model of a railway vehicle was built to measure the aerodynamic coefficients in five directions—side force, lift force, roll moment, pitch moment, and yaw moment—through a wind tunnel test. The data collected were applied as external forces to a full-scale railway vehicle model traveling on a curved track. Using a multibody simulation software program, SIMPACK, a railway vehicle was modeled, which was then used in the simulation of the dynamic characteristics and safety of vehicles while traveling on a curved track during a wind gust. Using the actual measured track data from the curved zone, a comparison was made on the dynamic characteristics of the car traveling, with and without a wind gust, on a curved track with a railway curve radius of 599 m; also, the difference was analyzed with the direction of the wind gust blowing from inside and toward the center of curvature. The results showed that in the presence of a wind gust blowing from outside the curvature with an average speed of 25 m/s it is advisable to stop train services on grounds of safety.

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Davis IV, John J., and Allison H. Gruber. "Quantifying exposure to running for meaningful insights into running-related injuries." BMJ Open Sport & Exercise Medicine 5, no. 1 (October 2019): e000613. http://dx.doi.org/10.1136/bmjsem-2019-000613.

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The very term ‘running-related overuse injury’ implies the importance of ‘use’, or exposure, to running. Risk factors for running-related injury can be better understood when exposure to running is quantified using either external or internal training loads. The advent of objective methods for quantifying exposure to running, such as global positioning system watches, smartphones, commercial activity monitors and research-grade wearable sensors, make it possible for researchers, coaches and clinicians to track exposure to running with unprecedented detail. This viewpoint discusses practical issues surrounding the use and analysis of data from such devices, including how wearable devices can be used to assess both internal and external training loads. We advocate for an integrative approach where data from multiple sources are used in combination to directly measure exposure to running in diverse settings.

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Pyne, David B., Philo U. Saunders, Amanda J. Cox, and Will G. Hopkins. "Do Seasonal Changes In Physiological Measures In An Incremental Running Test Track Peak Running Speed?" Medicine & Science in Sports & Exercise 40, Supplement (May 2008): S420. http://dx.doi.org/10.1249/01.mss.0000322789.52574.d4.

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44

Smirnov, V. I., and S. A. Vidiushenkov. "On equilibrium slope of station gradient." Proceedings of Petersburg Transport University 17, no. 4 (December 2020): 575–82. http://dx.doi.org/10.20295/1815-588x-2020-4-575-582.

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Objective: Defi nition of slope gradient for station track profi le elevation at which self-induced runningoff of loose running stock. Methods: Simulation of rolling stock movement based on analytical solution of differential equation of equilibrium of cut of wagons. Cut of wagons on station track is treated as a solid on a gradient plane with a mass equal to the mass of the cut of wagons. Track profi le elevation is approximated by piecewise-linear right line. Results: The paper shows that hopper wagons have the highest probability of self-induced running-off due to high air resistance coeffi cient. For three-element profi le the hypothetic wind speed at which running-off of wagons is possible remains relatively low, about 14 metres per second, which leaves the problem of effective fastening of wagons at stations still current. Practical importance: The solution obtained permits evaluating the probability of running-off of loose rolling stock under the action of gravity and under the impact of wind loading, as well as refi ne the norms for fastening of wagons at a station. The proposed calculation scheme also permits gauging the strength with which moving wagons would impact the backing thrust in case it is installed at the end of a track section.

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Li, Mingfei, and Junwei Liu. "Safety Analysis of the Running Train under Earthquake Dynamic Disturbance." Shock and Vibration 2021 (January 18, 2021): 1–21. http://dx.doi.org/10.1155/2021/6668274.

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Focusing on the safe operation of rail transit during earthquakes, the finite element method is used to construct a wheel-track-subgrade dynamics model in this study. Through spring-damper units, the relationship between the rail and the track slab and the connection between the track slab and the subgrade are established. A method for establishing a viscoelastic artificial boundary is proposed. Four seismic waves—the Tianjin wave, the El Centro wave, the Taft wave, and the Qian’an wave—are selected as the seismic input waveforms, and only the impact of the lateral ground motion on the wheel-track-subgrade system is considered. In this paper, the ground motion problem is transformed into a wave source problem, the seismic input is transformed into an equivalent load acting on the artificial boundary, and the wave input of the viscoelastic artificial boundary is realized. The normalization method is used to process the seismic waves, and a method that converts the input of the seismic waves into equivalent loads is proposed. The changing laws of different dynamic response indexes under the influence of the four waveforms are studied. Under the action of the Tianjin wave, the wheel-rail dynamic response is very violent near the acceleration peak, whereas, after the peak, all dynamic response indexes are within a safe range. Under the effect of the El Centro wave, the collision between the wheel and the track is relatively violent, and the train is already in a dangerous state. Under the action of the Taft wave, due to the sudden action of the peak ground motion acceleration, the displacement between the wheel and the track increases instantaneously, causing the train to derail. Under the action of the Qian’an wave, the force between the wheel and rail changes approximately linearly with respect to the frequency of the ground motion, and all dynamic response indexes are within a safe range. The vibration intensity of the four seismic waves is amplified by an intensity expansion factor. Except for the Tianjin wave, the amplified seismic wave has a greater impact on safe train operations. This paper can provide a reference for research on the running safety of trains under similar dynamic disturbance conditions.

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Kim, Chul Su, Gil Hyun Kang, and Seung Ho Jang. "A Study on the Development of the Korean Gauge-Adjustable Wheelset System for Freight Train." Advanced Materials Research 199-200 (February 2011): 337–40. http://dx.doi.org/10.4028/www.scientific.net/amr.199-200.337.

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To reduce the cost and the time of transport in Eurasian railroad networks such as TKR(Trans-Korea Railway), TCR(Trans-China Railway) and TSR(Trans-Siberia Railway) owing to the problem of different track gauges (narrow/standard/broad gauge), it is important to develop the gauge-adjustable wheelset (GAW) system to adapt easily to these gauges. The GAW system in the transcontinental railway represents a more effective way in comparison with other techniques for overcoming difference in track gauges. Freight trains having the GAW system will be passing various curved tracks in railroad networks. In this study, it was performed to evaluate contact stress and fatigue life of locking parts during freight trains' service in the curved track, respectively. Moreover, the safety of Korean GAW system at running track was verified by rig tests according to UIC 510-4 code.

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Cho, Sanghyeon, Kyoung-Chan Lee, Seung Yup Jang, Ilwha Lee, and Wonseok Chung. "Sequential Track–Bridge Interaction Analysis of Quick-Hardening Track on Bridge Considering Interlayer Friction." Applied Sciences 10, no. 15 (July 23, 2020): 5066. http://dx.doi.org/10.3390/app10155066.

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A quick-hardening track (QHT) was developed by injecting quick-hardening mortar into an existing ballast track to rapidly substitute the ballast track with a slab track, thereby improving maintainability and running safety. QHT tracks on a bridge undergo track–bridge interactions similar to other track systems. This paper presents a model to analyze the interaction between the QHT and the bridge. This model considers the longitudinal resistances of rail fasteners and anchors, as well as the interlayer friction between the track and the bridge. A sequential analysis method was applied to systematically consider such effects, revealing that rail additional stress will be high if the track slips over the bridge for a very low frictional coefficient of 0.1. Furthermore, a track segment without an anchor can slip under train traction load when the frictional coefficient is 0.3 or lower. For low friction cases, low-speed operation is advised to prevent the accumulation of the resulting longitudinal slip displacements of the track. An anchor should be installed immediately after the quick-hardening mortar provides sufficient bearing strength to the anchors. The proposed sequential analysis is useful for determining the critical friction coefficient and appropriate longitudinal resistance of a rail fastener, as well as for verifying track safety.

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Petrov, Anton, Kirill Yeliseyev, Alexander Tretyakov, Alexander Marykyn, Victor Nikityn, Mariya Zymakova, and Pavel Kozlov. "COMPARATIVE ANALYSIS OF THE RESULTS OF FORCE IMPACT ON THE TRACK WITH APPLICATION OF SCHLUMPF, “RZhD-2016” AND “NVTs-TKP” METHODS." Bulletin of scientific research results, no. 4 (December 17, 2017): 174–89. http://dx.doi.org/10.20295/2223-9987-2017-4-174-189.

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Objective: To improve the integrity of running and dynamic testing results of force impact on the track, on the basis of modern facilities of data logging and wireless transmission from rotary elements of a car, as well as the change from indirect to direct methods of measurement. Methods: Comparative running and dynamic tests of the impact on the track were held simultaneously on the same section of the track, using three methods of logging vertical and side forces, that is Schlumpf (State Standard R 55050-2012), “RZhD-2016” and “NVTs-TKP” methods. The key difference of the third method was the application of strain-gauge set of wheels (TKP), making it possible to keep a continuous record of forces acting in the “wheel-rail” system throughout the track, whereas other methods allowed for the realization of the above mentioned only on districts with a limited amount of sections. Results: According to the results of comparative testing, a conclusion was made on the improvement of integrity and justification of the method of “NVTs-TKP” with an application of strain-gauge set of wheels. Practical importance: It was suggested to apply “NVTs-TKP” method to implementing organizations of running and dynamic tests when evaluating the load of an innovative rolling stock on the track.

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Kardas-Cinal, Ewa. "Running safety of a railway vehicle in the presence of random track irregularities." Rail Vehicles, no. 4 (November 2, 2012): 1–10. http://dx.doi.org/10.53502/rail-139450.

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The paper presents the author�s investigations on dynamics of a railway vehicle, especially the effect of various factors on the running safety. The applied simulation methods used for analysis of running safety are in agreement the technical standards UIC 518 and EN 14363. The numerical simulations are performed for non-linear model of railway vehicle (a passenger car) moving along a tangent track with lateral and vertical geometrical irregularities of random character. The obtained results are used to study how the derailment coefficient is affected by the ride velocity, the parameters of the primary and secondary vehicle suspension, the wear of wheel and rail profiles as well as the track condition. The investigation of running safety is further enhanced by performing the spectral analysis of the dynamical responses of the railway vehicle-track system. It is found that there is a direct relation between the obtained power spectral density (PSD) of the derailment coefficient and the PSD of the lateral and angular wheelset displacements showing the characteristic oscillations due to the wheelset hunting. Finally, the paper presents the results of the statistical analysis of local track geometrical irregularities occurring in the vicinity of the track points where the derailment coefficient attains large values.

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Chen, Zhaowei. "Evaluation of longitudinal connected track under combined action of running train and long-term bridge deformation." Journal of Vibration and Control 26, no. 7-8 (December 13, 2019): 599–609. http://dx.doi.org/10.1177/1077546319889855.

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With long-term operation of high-speed railways, bridge deformation is hard to avoid, which directly affects the mechanical property of longitudinal connected track. To ensure the structural stability of longitudinal connected track and operation safety of train, this work proposes a work to evaluate longitudinal connected track under combined action of running train and long-term bridge deformation. First, the methodology of evaluating longitudinal connected track subject to train load and long-term bridge deformation has been proposed, in which an accurate train–track–bridge dynamic model and the method to determine long-term bridge deformation are settled. Then, the long-term bridge deformations caused by concrete creep, shrinkage, temperature, and pier settlement are investigated. On this basis, the evaluation of longitudinal connected track subject to long-term bridge deformation and running train is conducted, and the safety value of pier settlement for Chinese high-speed railways with longitudinal connected track is suggested. Results show that the long-term bridge deformations are even larger than the amplitude of random rail irregularity. With smaller settlement, influences of creep, shrinkage, and temperature play the leading role in affecting the mechanical behavior of longitudinal connected track, while influence of pier settlement occupies the dominant position with larger settlement. It is suggested that the pier settlement for Chinese high-speed railways with longitudinal connected track should be less than 7.7 mm to ensure structural stability of track and operation safety of train.

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Journal articles on the topic 'Track running'

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