Journal articles on the topic 'Resistance maximale en traction'
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1
Battiato, A., and E. Diserens. "Influence of Soil on the Traction Performance of a 65 kW MFWD Tractor." Journal of Agricultural Science 11, no. 17 (October 15, 2019): 11. http://dx.doi.org/10.5539/jas.v11n17p11.
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This study aimed to investigate the influence of the mechanical behaviour of the soil surface on the traction performance and the fuel consumption of an agricultural tractor, both in qualitative and in quantitative terms, in order to increase the consciousness about the major role of the soil mechanical response in the optimisation of the energy aspects involved in the traction developed by a tractor and promote the development of new strategies to reduce costs of tillage management and improve agricultural sustainability. The traction performance of a 65 kW MFWD tractor at tyre pressures of 60 and 160 kPa was compared on four Swiss agricultural soils: a clay with corn stubbles, a clay loam with wheat stubbles, a silty loam and a loamy sand both with corn stubbles. Tests performed with a bevameter pointed out noticeable differences in the mechanical behaviour of the soils. According to such differences, the drawbar pull on the four soils was significantly disparate with differences in maximal values of about 16% at a tyre pressure of 60 kPa and up to 37% at a tyre pressure of 160 kPa. Simulations with a semi-empirical tractor-soil interaction model also showed dissimilarities in traction coefficient, motion resistance, and traction efficiency. Measurements of the fuel consumption pointed out the presence of a narrow slip range where the specific fuel consumption SFC is minimised. This range doesn’t vary significantly among the considered soils as well as with the tyre pressure and doesn’t differ very much from the range where the power delivery efficiency is maximised. The SFC differed for almost 20% among the considered soils at a tyre pressure of 60 kPa and for ca. 10% at a tyre pressure of 160 kPa. The increase in tyre pressure from 60 to 160 kPa produced an increment in SFC up to 16%. The results of this study clearly pointed out how the traction performance is a characteristic of the tractor-soil system and not of the tractor only, therefore, a proper knowledge of the soil mechanical behaviour should aid in developing strategies oriented towards reducing fossil fuel consumption.
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Kader Hounsouho Lingani, Abdel, Siedouba Georges Ye, Sie Kam, and Dieudonne Joseph Bathiebo. "ETUDE DES CARACTERISTIQUES MECANIQUES DE VARIETES DE TUBERCULES DIGNAME, DE PATATE ET DE MANIOC CONSOMMES AU BURKINA FASO." International Journal of Advanced Research 9, no. 10 (October 31, 2021): 795–804. http://dx.doi.org/10.21474/ijar01/13612.
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Lobjectif de cette etude est letude des caracteristiques mecaniques de varietes de tubercules dignames, de patates et de manioc consommes au Burkina Faso. Deux varietes ont ete etudiees par tubercules et les principaux paramètres mecaniques etudies sont la resistance à la penetration des tubercules et leurs forces maximales de decoupe. Un banc dessai traction compression muni dun capteur de compression dune force maximale de 2000 Newton (N) a ete utilise à cet effet.Un outil de decoupe ainsi quune tige ont ete utilises respectivement pour la decoupe des tubercules en tranche et pour leur penetration. Six (06) plages de vitesses (15, 30, 45, 60, 75, 90 mm/s) ont ete utilisees pour la decoupe des tubercules en tranches, et une vitesse de 20 mm/s pour la penetration. Les teneurs en eau moyennes des tubercules etudiees etaient comprises entre 58,8±1,8 % et 77,1 ± 1,8 %. Lanalyse des resultats des tests de durete et de decoupe des tubercules nous ont permis dobtenir leurs forces maximales de penetration qui sont de 145 N pour ligname bêtê bêtê, 216 N pour la patate douce fadanga blanche et 391 N pour le manioc kalagè.Les forces maximales de decoupe sont de 311 N pour ligname gogo, 347 N pour le manioc kalagè et 410 N pour la patate douce fadanga blanche. Cette etude nous permet de mieux comprendre les facteurs pouvant affecter lefficacite de decoupe des tubercules. Les donnees de cette etude peuvent être dintegrees dans le dimensionnement des motorisations des equipements de transformation post-recolte des tubercules en vue de leur optimisation energetique.
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Van de Graaff, W. B. "Thoracic influence on upper airway patency." Journal of Applied Physiology 65, no. 5 (November 1, 1988): 2124–31. http://dx.doi.org/10.1152/jappl.1988.65.5.2124.
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Patency of the upper airway (UA) is usually considered to be maintained by the activity of muscles in the head and neck. These include cervical muscles that provide caudal traction on the UA. The thorax also applies caudal traction to the UA. To observe whether this thoracic traction can also improve UA patency, we measured resistance of the UA (RUA) during breathing in the presence and absence of UA muscle activity. Fifteen anesthetized dogs breathed through tracheostomy tubes. RUA was calculated from the pressure drop of a constant flow through the isolated UA. RUA decreased 31 +/- 5% (SEM) during inspiration. After hyperventilating seven of these dogs to apnea, we maximally stimulated the phrenic nerves to produce paced diaphragmatic breathing. Despite absence of UA muscle activity, RUA fell 51 +/- 11% during inspiration. Graded changes were produced by reduced stimulation. In six other dogs we denervated all UA muscles. RUA still fell 25 +/- 7% with inspiration in these spontaneously breathing animals. When all caudal ventrolateral cervical structures mechanically linking the thorax to the UA were severed, RUA increased and respiratory fluctuations ceased. These findings indicate that tonic and phasic forces generated by the thorax can improve UA patency. Inspiratory increases in UA patency cannot be attributed solely to activity of UA muscles.
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Zapałowicz, Krzysztof, and Maciej Radek. "The distribution of brachial plexus lesions after experimental traction: a cadaveric study." Journal of Neurosurgery: Spine 29, no. 6 (December 2018): 704–10. http://dx.doi.org/10.3171/2018.5.spine171148.
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OBJECTIVEThe objective of the present study was to determine experimentally the distribution of lesions caused in the cadaveric brachial plexus (BP) by excessive stretching. The authors attempted to delineate the correlation between the direction of stretching and sites of lesions.METHODSFifteen specimens (each comprised the spinal segment C4–T2 with 2 BPs) were harvested from adult cadavers. Each BP was stretched in a mechanical testing machine at a constant speed of 200 mm/min. Specimens were divided into 3 groups: in group A the BPs were stretched caudally at a 45° angle to the spinal midline; in group B they were stretched perpendicularly to the spinal midline; and in group C the stretching was caudally parallel to the midline. Lesions of each BP were identified and analyzed. A graph of load against dislocation was registered when stretching to delineate the maximal force (Fmax), defined as the maximum load at which BP failure occurs.RESULTSBased on macroscopic examination, 140 sites of mechanical damage were identified in 30 BPs. Preganglionic injuries (63.6% of lesions), defined as avulsions of the spinal ganglia with their rootlets, were found in 89 spinal nerves. In group B—in which specimens were stretched perpendicularly to the spinal segment—preganglionic injuries were significantly more frequent (41 avulsed spinal nerves) than in groups A and C (21 and 27 avulsed spinal nerves, respectively). Postganglionic lesions equivalent to neurotmesis were found in 51 sites (36.4% of all lesions) along spinal nerves, trunks, divisions, and cords. Postganglionic lesions in group B were much less frequent (8) as compared with groups A and C (24 and 19, respectively).CONCLUSIONSPredominance of preganglionic lesions suggests that attachments of the BP to the spine are more susceptible to traction than postganglionic elements. Preganglionic lesions were mainly produced in C7, C8, and T1 spinal nerves, suggesting their weaker attachment to the spine than in the case of C5 and C6 nerves. Preganglionic lesions were highly correlated with a traction perpendicular to the spine, whereas postganglionic lesions were provoked mainly by traction directed at 45° caudally or by means of caudal traction parallel to the midline. This discrepancy implies a relationship between mechanical resistance of pre- and postganglionic elements of the BP and the vector of force.
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Murphy, Erin H., Eric D. Johnson, and Frank R. Arko. "Device-Specific Resistance to in Vivo Displacement of Stent-Grafts Implanted with Maximum Iliac Fixation." Journal of Endovascular Therapy 14, no. 4 (August 2007): 585–92. http://dx.doi.org/10.1177/152660280701400422.
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Purpose: To compare the in vivo device-specific downward displacement force of various externally supported endografts implanted with maximum iliac fixation. Methods: Twenty female sheep had aneurysms created with a graft patch in the infrarenal aorta. In 12 animals, a fully supported modular bifurcated stent-graft [AneuRx (n=4), Talent (n=4), or Zenith (n=4)] was deployed; in the other 8, a bifurcated aortic graft was surgically anastomosed to the infrarenal aorta. All grafts were displaced in vivo by applying downward traction to a guidewire brought out both femoral arteries. The peak force to cause initial stent-graft migration or disruption of the sutured anastomosis was recorded and compared. Results: There was no difference in animal size, aortic neck diameter or length, aneurysm size, or iliac artery diameter for animals receiving the AneuRx, Talent, or Zenith stent-grafts and those undergoing surgical repair. The mean length of iliac fixation was 31.0±0.3 mm, 30.8±0.5 mm, and 31.3±0.6 mm for the AneuRx, Talent, and Zenith devices, respectively (p=NS). Peak force to initiate migration was 30.2=5.5 N (range 25–38) for the AneuRx, 44.8±5.5 N (range 40–53) for the Talent, 46.7±5.4 N (range 38–55) for the Zenith, and 40.6±7.5 N (range 31–50) for the surgical anastomosis (p=0.01). There was no difference detected in the peak force to initiate migration between the suprarenally affixed Talent and Zenith stent-grafts and the surgical anastomosis (p=0.55). Conclusion: Devices with a suprarenal component require significantly greater force to cause downward displacement compared to infrarenal devices. The force required to displace a suprarenal device with maximal iliac fixation was equivalent to the force required to disrupt a surgical anastomosis.
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Zhang, Rui, Dianlei Han, Guolong Yu, Haitao Wang, Haibao Liu, Haibin Yu, and Jianqiao Li. "Bionic research on spikes based on the tractive characteristics of ostrich foot toenail." SIMULATION 96, no. 9 (June 10, 2020): 713–23. http://dx.doi.org/10.1177/0037549720927080.
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Inspired by the superior fixed and traction characteristics of ostrich foot toenails, we devised, optimized and manufactured the single structure and group arrangement of a new-style bionic spike for sprint shoes to improve athletic performance. The tractive performance of the bionic spike was tested by finite element analysis and experimental verification. The optimized single structure of the bionic spike had a top slope angle of 13° and the radius of the medial groove of 7.3 mm. Compared with the conventional conic spike, the maximal and stable extrusion resistances of the single bionic spike decreased by about 25% and 40% respectively, while the maximal and stable horizontal thrusts increased by about 16% and 10%, respectively. In addition, the arrangement of the bionic spikes was also optimized. Compared with the conventional spike group, the maximal and stable extrusion resistances of the bionic spike group decreased by 11.0% and 6.2%, respectively, while the maximal and stable horizontal thrusts increased by 20.0% and 16.0%, respectively. The current results may provide useful mechanical information that can help develop a better design of athletic shoes with the potential for advanced performance.
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Pavlov, I. M., and A. E. Sarsenov. "Coulter’s traction resistance." Agrarian Scientific Journal, no. 2 (February 20, 2017): 64–66. http://dx.doi.org/10.28983/asj.v0i2.35.
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Begunov, M. A., V. S. Koval, and E. V. Demchuk. "Coulter Traction Resistance Analysis." IOP Conference Series: Earth and Environmental Science 666, no. 5 (March 1, 2021): 052034. http://dx.doi.org/10.1088/1755-1315/666/5/052034.
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Ka, S., PS Dieng, J. Thiam, MM Dieng, S. Kobinama, and A. Dem. "C113: Exérèse large sous anesthésie locale des tumeurs suspectes du sein : une technique pour sécuriser les marges." African Journal of Oncology 2, no. 1 Supplement (March 1, 2022): S47. http://dx.doi.org/10.54266/ajo.2.1s.c113.umpg1519.
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INTRODUCTION : La discordance clinique dans le diagnostic des masses mammaires impose une approche chirurgicale à minima respectant des principes carcinologiques. Nous rapportons une technique d’exérèse large des nodules mammaires sous anesthésie locale. MATERIELS ET METHODES : Nous utilisons 15 cc de xylocaine à 1% diluée dans une cupule avec 20 cc de sérum physiologique. L’infiltration se fait sur les points cardinaux puis sous la lésion. Puis, nous infiltrons sous la ligne d’incision cinq cc de xylocaine non diluée. L’incision est faite en quartier d’orange et l’exérèse est faite grâce à une traction au zénith de la lésion suivie d’une dissection circulaire. RESULTATS : Dix patientes ont été opérées. Les lésions étaient toutes à distance de l’aréole. La taille maximale était de quatre cm. Il n’y avait pas d’incident ni d’accident. Les suites opératoires étaient simples et toutes les marges était saines à l’histopathologie. CONCLUSION : L’exérèse sous anesthésie locale de tumeurs du sein dans le cadre de l’exploration d’un trépied discordant utilisant la traction au zénith est une technique simple et sure pour garantir la sécurité des marges.
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Kurbаnov, Sherzod, Isroil Temirov, Yorkinoy Khashimova, Parakhat Berdimuratov, and Said Yuldoshev. "Pulling resistance of the front plow cornercutter." E3S Web of Conferences 383 (2023): 04012. http://dx.doi.org/10.1051/e3sconf/202338304012.
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When installed on the frontal plow, the bodies will work in conditions of semi-blocked cutting. The purpose of the study is the theoretical determination of the traction resistance of the frontal plough's cornercutter. The basic principles and methods of classical mechanics, mathematical analysis and statistics were used in this study. Analytical equations for determination of traction resistance of cornercutter beam and plough have been obtained. It is established that traction resistance of frontal plough corners depends on cornersner and plough parameters as well as on physical-mechanical soil properties. At speeds of 1.8-2.3 m/s, traction resistance of the corrugated plough is 0.36-0.39 kN.
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Sun, Wei, Jian Min Wu, Lin Rong Shi, Hua Zhang, Tao Li, and Jing Kao. "Drag Reduction Performance Parameter Optimization of Vibration Digging Shovel." Advanced Materials Research 926-930 (May 2014): 777–80. http://dx.doi.org/10.4028/www.scientific.net/amr.926-930.777.
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In order to optimize vibration digging shovels drag reduction performance parameter, building the regression model of traction resistance between vibration frequency and amplitude, penetrating angle and the traction rate based on the vibration reduction simulation experiment results, moreover, it is optimized. The results show that the effect factors of traction resistance from high to low is the vibration frequency, the traction rate, penetrating angle, amplitude. When the drawing speed is 0.67 m/s, the vibration frequency is 13.77 Hz, vibration amplitude is 11.93 mm, penetrating angle is 8.35 °, optimization value of traction resistance is 1449.59 N. Test results show that: the field test resistance average and the simulation results error is less than 5%, which illustrate that the regression model can better reflect the relationship between the vibration frequency, traction rate, penetrating angle, amplitude and traction resistance.
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Batirov, Zafar, Shuhrat Sharipov, Yokubjon Mahmudov, Shakhboz Azizov, and Obid Mamadiyorov. "Traction resistance of a ripper with a current distribution line." E3S Web of Conferences 264 (2021): 04050. http://dx.doi.org/10.1051/e3sconf/202126404050.
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The pipeline distributor carries out deep loosening of the soil and three-tier fertilization. The study aims to determine the traction resistance of the working body of the ripper with a distribution pipe. The study uses the basic provisions of mathematics, theoretical mechanics, and agricultural mechanics. The method of calculating the traction resistance of the cultivator-fertilizer equipped with pipelines-distributors for three-tier fertilization is presented. The components of the balance of traction resistance are determined. Analytical dependencies are obtained for determining the traction resistance of the working body of the ripper with a distribution pipe. It has been established that the traction of the ripper working body with the fertilizer distributor depends on the physical and mechanical properties of the soil, the blade thickness and length of the chisel blade, the length of the working surface of the share, the angle of crumbling and the solution of the share, the width of the working body and the speed of movement. The traction resistance of the pipeline is 12-12.5% of the traction resistance of the rack and 4-5% of the total traction resistance of the ripper working body.
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Erzamaev, Maxim P., Dmitry S. Sazonov, Alexander E. Afonin, Leila S. Kurmanova, and Evgeny S. Nesterov. "Universal equipment for determining traction resistance of working bodies and their combinations designed for soil treatment." BIO Web of Conferences 17 (2020): 00010. http://dx.doi.org/10.1051/bioconf/20201700010.
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The article describes a strain gauge measuring system designed for measuring the traction resistance of tillage bodies and their combinations. Technical tools measure the traction resistance of the whole machine or one working body which is not an objective and reliable characteristics of combined tillage units. The design and principle of operation of the tensometric measuring system designed and manufactured by Samara State Agrarian University is described. It is used to determine the traction resistance of individual working bodies and their combinations. The results show that the measurement data on traction resistance are in compliance with the calculated values.
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Gumarov, Gali S., Vladimir V. Konovalov, Amangeldy E. Sarsenov, Zhanna K. Kubasheva, and Abelshaek A. Rakhimov. "Mathematical modelling of traction resistance of the improved opener of grain seeder." BIO Web of Conferences 17 (2020): 00044. http://dx.doi.org/10.1051/bioconf/20201700044.
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The object of the study is a double disc coulter with a pressure plate. The aim of the research was to simulate the operation of the double disc coulter using a grain seed drill as an example. Analytical dependencies for determining the traction resistance of the improved coulter are presented. The method of calculating the drag resistance of a double disc coulter with an original pressure plate installed on it is given. The components of the traction resistance balance have been determined and the dependence on the sowing depth has been established. 3D graphical dependences of the traction resistance of serial and advanced coulters on the speed and depth of its movement have been constructed based on the results of calculations. The main influence is the placement depth. Speed of movement of the seeder in the considered interval of its values does not render essential influence on traction resistance. Installation of an additional pressure plate increases traction resistance to 5 %.
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Liu, Kaihua, Marco Benetti, Marco Sozzi, Franco Gasparini, and Luigi Sartori. "Soil Compaction under Different Traction Resistance Conditions—A Case Study in North Italy." Agriculture 12, no. 11 (November 19, 2022): 1954. http://dx.doi.org/10.3390/agriculture12111954.
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Tractive efficiency is essential in tillage operations to optimise traction performance. In this field experiment, the tractor performance was measured under different traction resistance conditions. This study quantified the soil stress, soil bulk density, soil moisture, soil cone index, soil surface disturbance, rolling resistance and slip rate under different numbers of passes and traction conditions. The actual power used under different soil and traction conditions was collected. Fuel consumption and savings were calculated between uncompacted soil, compacted soil and the permanent traffic lane. The results show that soil stress increases in each location as traction and the number of passes increase. Soil’s physical properties increase, such as the soil bulk density, soil cone index and soil surface disturbance. Additionally, the slip rate increases with traction in each soil condition as uncompacted soil, compacted soil and the permanent traffic lane. The results show that the permanent traffic lane has a lower slip rate under different traction conditions than the uncompacted and compacted soil. Furthermore, the permanent traffic lane has less energy consumption with the same traction resistance. The permanent traffic lane saved 25.50%, 29.23% and 42.34% fuel compared to the uncompacted field in 7.85, 14.71 and 24.52 kN traction conditions, respectively. Our results confirm that dynamic factors such as traction and rolling resistance should be considered in soil compaction research rather than static weight only. In practice, the controlled traffic farming (CTF) system or driving the tractor more frequently on the permanent traffic lane should be considered to improve working efficiency and reduce energy consumption.
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Chuyanov, Dustmurod, Golib Shodmonov, Ibrat Ismailov, Gayrat Ergashov, and Akramjon Sadikov. "Traction resistance of the combined machine plough." E3S Web of Conferences 264 (2021): 04036. http://dx.doi.org/10.1051/e3sconf/202126404036.
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Subsoils are widely used on tillage and combination machines. The tiller of the combined machine for preparing the soil for sowing melons and gourds carries out strip loosening of the subsoil layers. The study aims to theoretically determine the traction resistance of a soil deepener of a combined machine for preparing the soil for sowing melons and gourds. The study uses the basic provisions of mathematics, theoretical mechanics, and agricultural mechanics. In studies, it is assumed that the destruction of the soil under the influence of the drill bit occurs by separation. The total traction resistance of the subsoiler was determined as the sum of the resistance of the rack and the bit. An analytical expression has been obtained to determine the traction resistance of a tilting machine with an inclined stand, depending on its design, technological parameters, and the physical and mechanical properties of the soil. As a result of theoretical studies, it was found that the traction resistance of the soil deepener is mainly influenced by its design parameters, the depth of soil cultivation, the physical and mechanical properties of the soil, and the speed of the machine.
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Mamatov, Farmon. "Traction Resistance of Soil Submersibility Type "Paraplau"." Journal of Advanced Research in Dynamical and Control Systems 12, SP7 (July 25, 2020): 2154–61. http://dx.doi.org/10.5373/jardcs/v12sp7/20202336.
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Derepaskin, A. I., and A. P. Komarov. "Justification of the layout of the working bodies of tillage implements according to the criteria of metal consumption and traction resistance." Machinery and Equipment for Rural Area, no. 8 (August 30, 2021): 10–13. http://dx.doi.org/10.33267/2072-9642-2021-8-10-13.
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The results of laboratory and field studies to determine the quantitative characteristics of the change in the traction resistance of the working bodies depending on their operation conditions in the soil environment are provided. The values of the traction resistance of the working bodies operating in different cutting modes have been determined. A method is proposed for a comparative assessment of various process flow sheets of tools according to the criteria of metal consumption and traction resistance.
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Shchirov, Vladimir Vladimirovich, Andrey Yuryevich Nesmiyan, Sergey Mikhaylovich Oldyrev, Sergey Vartanovich Asaturyan, and Yuriy Mikhaylovich Cheremisin. "The analysis of the traction resistance of the chisel plows." Agrarian Scientific Journal, no. 5 (May 28, 2019): 95–100. http://dx.doi.org/10.28983/asj.y2019i5pp95-100.
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The study analyzed the traction resistance of chisel plows when working on light clayey chernozem that is widespread in the southern arid part of Russia. On the basis of the research, the refined relationship was proposed to determine the traction resistance of chisel plows and the values of the empirical coefficients included in it with reference to light clayey soils. Calculated values of reduced traction resistance of chisel plows, obtained using the proposed expression and refined empirical coefficients, differ from experimental data by about 2.5 %.
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Salavat Mudarisov, Ilshat Gainullin, Ildar Gabitov, and Eduard Khasanov. "Improvement of Traction Indicators of a Track-Chain Tractor." Communications - Scientific letters of the University of Zilina 22, no. 3 (July 8, 2020): 89–102. http://dx.doi.org/10.26552/com.c.2020.3.89-102.
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The aim of this research was to conduct the comparative traction tests for T-170M1.03-55 tractor with a flat and elliptical rim. Structurally rational geometry of the crawler's support surface for tractors with semi-rigid suspension is realized by placing the support rollers at different heights relative to the cart. The results of traction tests showed that elliptical track rim has increased the maximum traction power by 10.4%, conditional traction propulsive efficiency coefficient to 7.43% and the specific traction effort by 8%. The increase in indicators is provided by a lower rolling resistance of a tractor with an elliptical rim. Reduction of the resistance power to rolling of the tractor with an ellipse track rim occurs due to alignment of support rollers vertical load and reduction of resistance to rollers movement on internal contours of tracks and in hinges of track chain links. The results of the research indicate a significant improvement in traction performance of T-170M1.03.55 tractors with elliptical track-chain rim.
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Makasheva, Svetlana, and Pavel Pinchukov. "Return traction current system’s operation in cold climate regions." MATEC Web of Conferences 265 (2019): 02009. http://dx.doi.org/10.1051/matecconf/201926502009.
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The paper deals the problem of the reverse traction current's asymmetry at the AC electrified railways. The features of return traction current system’s operation under conditions of cold climate are considered. The goal of work is to determinate value of return traction current asymmetry coefficient for cold climate regions operating AC electrified railways. To achieve the goal the methods of scientific analysis, imitation modelling, experimental study are used. Types and rationing of return traction current asymmetry are accented. The return traction current system model is created in Multisim 12.0 software for analyse the degree of various factors influence on the return traction current's asymmetry. Main influencing factors for asymmetry coefficient in cold climate regions as a traction current value and catenary tower resistance are considered. The calculated graphic dependences of the asymmetry coefficient as a function of the traction current and the catenary tower resistance are given. Algorithm for identifying the critical zones (hazardous areas) by graphical dependencies and predicting the system's predicament states is described.
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Gupta, Shubham, Sarabjeet Singh Sidhu, Subhodip Chatterjee, Ayush Malviya, Gurpreet Singh, and Arnab Chanda. "Effect of Floor Coatings on Slip-Resistance of Safety Shoes." Coatings 12, no. 10 (October 2, 2022): 1455. http://dx.doi.org/10.3390/coatings12101455.
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Slippery flooring often leads to unintentional slips and falls, which results in traumatic injuries. To reduce slipping risks, adequate traction at the shoe and flooring contact is essential. In addition, viscous slippery contaminants like water or oil reduce a floor’s traction performance and increase slipping hazards. In this work, the effect of commonly available protective floor coatings on the traction performance of safety-labelled shoes was extensively studied. The study included three floor coatings, namely acid-based etchant coating, epoxy floor paint, and polyurethane, which were tested across five safety shoes. The coated floorings were tested using a robotic slip-testing device in dry and in the presence of water and machine oil—as separate contaminants. The application of floor coatings produced varying surface roughness for the flooring. Significant traction was generated by the etchant coating for the dry flooring, epoxy coating for the wet flooring, and polyurethane coating for all flooring conditions. A comparison of uncoated and coated floorings showed a high effectiveness of generating traction with epoxy coating on wet flooring and polyurethane coating on both wet and oily conditions. The study results are novel and are anticipated to provide valuable guidelines for the selection of slip-resistant coatings for different slippery floorings, and to reduce risks related to slips and falls.
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Šmerda, Tomáš, and František Bauer. "Effect of the load of drive axles and high of the curtain on stress-strain properties of the tractor." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 55, no. 4 (2007): 77–88. http://dx.doi.org/10.11118/actaun200755040077.
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The goal of the experimental measurement was determination of relation among weight load of the tractor together, hitch height changes and drawbar characteristic. The measurement was realized on chassis dynamometer at MUAF in Brno. The first step consisted of rated speed characteristics measurement in conformity with OECD demands. The drawbar characteristic was measured under two selected gears. Adding 980 kg to the nominal wight of the tractor brought increasing maximal drawbar power and drawbar force together with decreasing of slip. The highest differences were observed during the mesurement of fifth gear shifted. The drawbar force grew up to 18.9% as well as the maximal drawbar power (15.2%). The maximal drawbar power at ninth gear gave 62.8 kW. The hitch height was setting to 0.54 m; 0.64 m and 0.74 m. When the hitch height was set from 0.54 m to 0.74 m the drawbar force an power on front axle was lower by reason of load reduction. As can be noticed from the final drawbar characteristics, both curves are identical up to border of maximal drawbar power. Small differences in the area of the highest slips can be ascribed to the rolling resistance.
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Kosarev, A. B., and B. I. Kosarev. "Calculation methodology of current distribution in traction networks of AC current." Vestnik of the Railway Research Institute 76, no. 6 (December 28, 2017): 329–35. http://dx.doi.org/10.21780/2223-9731-2017-76-6-329-335.
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Several publications have been devoted to the development of traction power supply for alternating current [1, 2]. They set the task of considering the resistance of the external power supply system and power traction transformers when calculating the current distribution in traction networks. With all the merits of the existing methods for calculating these resistances, there are discrepancies in the published sources in determining the parameters of the equivalent circuit for the traction power supply system [3, 4, 5, 6]. In the present work, the authors propose a technique for calculating reduced to a voltage of 27.5 kV equivalent resistances of an external power supply system and a power traction transformer. An equivalent circuit for replacing the traction power supply system is substantiated, allowing to take into account the voltage drop on the overall resistance of the external power supply system from the traction currents of the considered and adjacent feeder zones, as well as transit currents flowing through the power lines. Using the method of symmetrical components it was obtained that when calculating the internal resistance of a traction substation consisting of the resistances of the longitudinal power supply line and the power traction transformer, it is necessary to use the calculated formulas obtained when taking into account the actual current distribution in the secondary (traction) winding of the power traction transformer. It is shown that the traction network equivalent circuit for the calculation of short-circuit currents, given in [1, 2], does not reflect the real current distribution relationships in traction networks. The main reason for the inconsistency of the scheme proposed by a number of experts with the existing traction power supply system is determined by an unjustified transition from an asymmetric system “three-phase transmission line - transformer - power supply system - single-phase traction network” to a single-line calculation scheme. When calculating the current distribution according to this scheme, there is no metallic connection of the track with one of the phases (more often phase C ) of the power traction transformer. The absence of this connection leads to the flow of traction currents between the district and traction substations, short-circuit current on the ground, which is not permissible.
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Shoop, S. "Electric Vehicle Traction and Rolling Resistance in Winter." Tire Science and Technology 26, no. 2 (April 1, 1998): 64–83. http://dx.doi.org/10.2346/1.2135963.
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Abstract Low rolling resistance tires help optimize the economy of electric vehicle (EV) operation. Five types of EV tires were evaluated under cold weather conditions and compared with traditional winter tires in terms of traction and rolling resistance. Other contributions to vehicle resistance (brake drag, wheel bearing resistance, driveline resistance, and air drag) were also measured and used to estimate changes in total vehicle resistance and associated changes in range with temperature. At low speeds, tire rolling resistance is the primary contribution to increased vehicle resistance at cold temperatures, with snow tires having both higher resistance and a stronger dependence on temperature than low rolling resistance tires. Lowering tire pressure increases both resistance and temperature dependence for most tires but also improves traction and therefore may serve as a temporary safety measure in winter conditions.
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Petrov, Alexander, Yuri Saveliev, Pavel Ishkin, and Mikhail Petrov. "Soil tillage energy efficiency increase." BIO Web of Conferences 17 (2020): 00177. http://dx.doi.org/10.1051/bioconf/20201700177.
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Tillage energy efficiency increase is one of the important tasks in improving the profitability and sustainability of agricultural production. The paper proposes to increase cultivation energy efficiency due to the use of traction-drive tilling implement with active working bodies, not creating a high traction resistance and not requiring a large towing weight of aggregated tractor. The analysis of the energy efficiency of soil cultivation using traction-driven tilling implements with active working bodies has been carried out, and theoretical dependences of the coefficient of efficiency of a traction-driven machine-tractor unit has been obtained. The possibility of increasing the efficiency of the unit by reducing slipping of the tractor wheels and losses on rolling of the unit has been determined, which has been achieved by transferring part of the power through the power take-off shaft (PTO) of tractor to the drive working bodies of tilling implement, which compensate for traction resistance of the implement and create a pushing force, reducing the resistance to rolling.
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Kyurchev, Volodymyr, Nataliia Veselovska, and Serhii Burlaka. "INCREASING THE TRACTION AND TRACTION CHARACTERISTICS OF THE ENERGY VEHICLE WHEN CARRYING OUT COMBINED SOIL PROCESSING OPERATIONS." ENGINEERING, ENERGY, TRANSPORT AIC, no. 1(120) (May 1, 2023): 48–53. http://dx.doi.org/10.37128/2520-6168-2023-1-6.
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The article is devoted to the study of methods and means that help to improve traction and traction characteristics of power vehicles, in particular tractors, when performing combined operations of soil treatment. The article analyzes the impact of weight distribution, tire pressure, and the use of special devices on the quality of tillage operations. It was established that the efficiency of combined tillage operations depends on the level of traction and traction characteristics of the power tool. To increase traction characteristics of the tractor, it is proposed to use mathematical methods of increasing tire pressure and optimal weight distribution on the axle. The article also describes special devices for increasing traction resistance, which help to provide better traction and increase traction characteristics. This article examines the influence of soil parameters on traction and traction characteristics of an energy vehicle during combined soil treatment operations. It was found that soil indicators, such as moisture, density and fractional composition, have a significant impact on the quality of soil processing operations and traction characteristics of the tractor. To solve this problem, methods of increasing traction and traction characteristics are proposed, such as a mathematical method of increasing tire pressure and a method of optimal weight distribution on the suspension. The use of special devices to increase traction resistance, which help to ensure better traction and improve traction characteristics, is also considered. The research conducted by the authors can be useful for tillage and tractor maintenance specialists who are engaged in optimizing the operation of energy equipment at agricultural enterprises.
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Kaul, David, Eva Fallenberg, Felix Diekmann, Volker Budach, and Martin Maurer. "Dislocability of Localization Devices for Nonpalpable Breast Lesions: Experimental Results." Radiology Research and Practice 2014 (2014): 1–4. http://dx.doi.org/10.1155/2014/425823.
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Purpose. For accurate resection of nonpalpable malignant breast lesions with a tumor-free resection rim, an exact and stable wire localization is essential. We tested the resistance towards traction force of different localization devices used in our clinic for breast lesions in two types of tissue.Materials and Methods. Eight different commercially available hook-wire devices were examined for resistance towards traction force using an analogue spring scale.Results. Most systems showed a high level of movement already under small traction force. Retractable systems with round hooks such as the Bard DuaLok , the Fil d’Ariane, and the RPLN Breast Localization Device withstood less traction force than the other systems. However, the Bard DuaLok system was very resistant towards a small traction force of 50 g when compared to the other systems. The Ultrawire Breast Localization Device withstood the most traction force in softer tissue and Kopans Breast Lesion Localization Needle withstood the most force in harder tissue.Conclusion. The Ultrawire Breast Localization Device and Kopans Breast Lesion Localization Needle withstood the most traction force. In general retractable systems withstand less traction force than nonretractable systems.
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Smith, Robert H. "Traction Considerations during Stairway Descent." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 46, no. 10 (September 2002): 910–14. http://dx.doi.org/10.1177/154193120204601007.
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Investigations of actual pedestrian descent slips on dry stairway-tread nosings indicate that additional analysis of traction requirements during such activity is warranted. Limited bio-mechanical-traction-demand testing utilizing force plates on stairs have been conducted. Results from this work have been used to characterize currently accepted safety factors for stair-tread slip resistance as generous. However, two issues of relevance have not been considered. One is the angle of foot contact with the nosing, which can produce a ramp-effect. Ramp descent necessitates provision of greater slip resistance than does horizontal ambulation. Another is elastomeric friction behavior by shoe heel and -sole materials in contact with treads. in classical metallic theory, the coefficient of friction is directly proportional to the developed frictional resistance force divided by the applied normal load. This is not always so with elastomeric materials. With some elastomers, the friction coefficient decreases as applied normal forces increase. Because of this inverse response, focus widens to include both traction demand by the pedestrian and traction production in the footwear. The potential importance of foot-contact angles and the elastomeric-friction mechanism in stairway descent are assessed.
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Li, Shanjun, Zehua Yang, Qiang Wan, Jianfeng Hou, Yangyi Xiao, Xin Zhang, Rui Gao, and Liang Meng. "Increase in Wear Resistance of Traction Wheel via Chromizing: A Study Combining Experiments and Simulations." Coatings 12, no. 9 (September 2, 2022): 1275. http://dx.doi.org/10.3390/coatings12091275.
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The wear failure of traction wheels in orchard transport severely restricts the stability of orchard conveyors and impedes the mechanization of orchard work. In this study, the thermal-diffusion chromizing method was employed to increase the hardness of a traction wheel for the enhancement of wear resistance. The results show that a uniform and dense chrome coating with a thickness of 16 μm was formed on the surface. The coating was revealed to have a hardness of 1752.7 HV and benefited from the formation of Cr-C compounds. A friction test and a wear simulation test under both dry-friction and lubrication conditions were conducted to assess the enhanced wear resistance based on the friction coefficient and wear loss. The friction coefficient of QT400 and that of the chrome coating were 0.37 and 0.36, respectively, under dry conditions. Additionally, the friction coefficient of QT400 decreased to 0.12, while that of the chrome coating remained at 0.35, under lubrication conditions. In the wear simulation test, the wear loss of the chromed traction wheel was about 1/28 of that of the QT400 traction wheel under dry-friction conditions. In addition, the wear loss of the chromed traction wheel was about 1/24 of that of the QT400 traction wheel under lubrication conditions. Moreover, the wear mechanism was analyzed with a microstructure study and finite element analysis (FEA). The synergetic effect between fatigue wear and abrasive wear was likely responsible for the wear failure of the traction wheel. The method proposed in this study may be a promising way to enhance the wear resistance of QT400 traction wheels through the application of a chrome coating without sacrificing the loading capacity, and this work contributes to the understanding of the wear failure mechanism of traction wheels.
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Pitanuwat, Siriorn, Hirofumi Aoki, Satoru Iizuka, and Takayuki Morikawa. "Development of Hybrid-Vehicle Energy-Consumption Model for Transportation Applications—Part I: Driving-Power Equation Development and Coefficient Calibration." Energies 13, no. 2 (January 18, 2020): 476. http://dx.doi.org/10.3390/en13020476.
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This study is the first of a two-part paper. The overall study presents a new methodology to improve the accuracy of hybrid vehicles’ energy-consumption model over conventional transportation modeling methods. The first paper attempts to improve an equation for vehicles’ driving-power estimation to be more realistic and specific for a particular vehicle model or fleet. The second paper adopts the driving-power equation to estimate the requested driving power. Then, the data are utilized to construct the hybrid-vehicle energy-consumption model, namely, the traction-force–speed-based energy-consumption model (TFS model). The main concept of the first paper is to utilize the power-split hybrid powertrain’s accessible on-board diagnostics (OBD) dataset, and its dynamic model to estimate the total propulsion power. Then, propulsion power was applied as the main parameter for driving-power equation development and vehicle-specific coefficient calibration. For coefficient calibration, this study implemented the stepwise multiple regression method to select and calibrate an optimal set of coefficients. Results showed that conventional driving-power equations Vehicle-Specific Power (VSP) LDV 1999 and VSP Prius3Spec provide low prediction fidelity, especially under high-speed (>80 km/h) and heavy-load driving (≥50 kW). In contrast, D r v P w P r i u s 3 , proposed in this study, effectively improved prediction to become more accurate and reliable through all driving conditions and speed ranges. It dramatically helped to reduce prediction discrepancy over the conventional equations at heavy-load driving, from an R-square of 0.79 and 0.78 to 0.96. D r v P w P r i u s 3 also the prediction error at high-speed driving from the maximal error of approximately −20 to −5 kW. This study also discovered that aerodynamics and rolling resistance were the primary factors that caused the prediction error of conventional VSP equations. In addition, results in this study showed that both of the approaches used to establish the P P T d r v and D r v P w P r i u s 3 equations were valid for a power-split hybrid vehicle’s driving-power estimation. For the coefficient-calibration part, the stepwise and multiple regression method is low-cost and simple, allowing to calibrate an appropriate set of optimal coefficients for a specific vehicle model or fleet.
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Lenski, Aleksandr V., Aleksandr A. Zheshko, and Anna A. Aletdinova. "Construction of mathematical models to determine traction resistance." Far Eastern Agrarian Herald 16, no. 3 (2022): 96–106. http://dx.doi.org/10.22450/199996837_2022_3_96.
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Missirlis, Dimitris, Tamás Haraszti, Lara Heckmann, and Joachim P. Spatz. "Substrate Resistance to Traction Forces Controls Fibroblast Polarization." Biophysical Journal 119, no. 12 (December 2020): 2558–72. http://dx.doi.org/10.1016/j.bpj.2020.10.043.
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Zharkov, Yu I., N. A. Popova, and E. P. Figurnov. "Accounting power supply schemes for traction substations in the calculation of short circuits in the AC traction network." Vestnik of the Railway Research Institute 78, no. 1 (May 13, 2019): 10–18. http://dx.doi.org/10.21780/2223-9731-2019-78-1-10-18.
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When calculating short-circuit currents in the AC traction network, it is assumed that each of the traction substations receives power from uncoupled external power supply sources with known resistances. In some cases, especially when powering a group of traction substations from a high-voltage power line of a longitudinal power supply, the external power supply system affects not only the magnitude of short-circuit currents, but also their redistribution between adjacent traction substations of the interstation area where this circuit is considered. Such unrecorded redistribution can have a negative effect on short circuit protection. The article considers the equivalent circuit of the traction network, taking into account resistance of the external power supply system. Particular attention is paid to the fact that in replacement circuits of direct and negative sequence value of reduced resistance of one phase of a multiwinding transformer, calculated from the short circuit voltage, does not depend on the connection scheme of its windings. It is noted that in some cases it is difficult to obtain a complete scheme of an external power supply system. Considering that the short circuit in the traction network for the external power supply system is remote, it is proposed taking into account the reference network or traction substations as power sources, from which high-voltage transmission lines power the traction substations. Resistance of the supporting substations as power sources must takes into account connected equivalent power system.Such equivalenting should be carried out by known values of currents or short-circuit powers at the inputs of the reference substation or, if such information is not available, by the rated values of the switched-off currents or powers of the switches of high-voltage line connections.The following power schemes for traction substations are considered: each from its own supporting substation, which is part of an electrically uncoupled external power supply system; from the double-circuit high-voltage line of longitudinal power supply when it is powered from different supporting substations; from the supporting network substation, the traction substation receives power from two lines, and from this the traction substations receive power from two lines in a circle pattern.These three common cases cover all the most common power schemes for traction substations. For each of them formulas are given to determine the resulting equivalent resistance of the external power supply circuit, which should be taken into account in the replacement circuit of the traction network.
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Zhu, Xiao Yu, and Jian Yong Zuo. "Power Consumption Analysis of High-Speed Train’s Brake Discs." Advanced Materials Research 765-767 (September 2013): 120–24. http://dx.doi.org/10.4028/www.scientific.net/amr.765-767.120.
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Apart from the aerodynamic drag produced by transitional motion of high-speed train, the rotational parts of the train, especially the ventilated discs mounted on axles, would also cause resistance torques due to air pumping effect, which consume traction power. In this paper the train running process is divided into traction, uniform running and braking three phases, then the power consumed by the brake discs as well as the proportion of which in total traction or braking power during the three periods is calculated based on kinetic energy theorem. The results indicate that, during traction and uniform running period, the power consumption of brake discs shares 2.84% and 12.87% of total traction power, and in brake stage, the proportion is 0.78%. What is more, in the uniform running phase, the proportion of brake discs power consumption caused by resistance torque can reach to 7.68%. If the air inlet of brake disc is blocked during traction and uniform running period to weaken air pumping effect, the useless power consumption can be effectively reduced and the traction efficiency can be improved.
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Kurilkin, Dmitry, Vladimir Grachev, and Valeriy Tanaev. "Defining Resistance in Traction Motor Circuit According to Microprocessor Control System Data." Bulletin of scientific research results 2022, no. 4 (December 24, 2022): 74–89. http://dx.doi.org/10.20295/2223-9987-2022-4-74-89.
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Purpose: To develop methodology for determining the actual resistance of traction electric drive (TED) circuits of a locomotive with electric power transmission and with refined calculation of voltage losses of a collector-brush apparatus according to microprocessor control system data. These data are necessary for calculating actual traction characteristics of a locomotive as well as its braking characteristics in electric braking modes. Methods: Methods of electric machine theory, statistical processing and regression analysis of experimental data were used. Results: Based on the statistical analysis of registration data of on-board diagnostics subsystem of 20 sections of 2TE116U and TEP70BS diesel locomotives, methods for determining resistance factual value for traction electric drive circuit as well as methods of refined calculation for voltage losses in a collector-brush apparatus are proposed and justified. The hypothesis on distribution normal law for the value of resistance and the possibility to use its mathematical expectation as an estimated value is confirmed. The limits of resistance possible changes for TED circuits of diesel locomotives 2TE116U and TEP70BS have been established. Practical significance: The results obtained allow us to clarify energy loss amounts in a locomotive traction drive when calculating its traction and braking characteristics. Data on the limits, allowed in exploitation, of active resistance change for TED serviceable chains may be used for operative diagnostics of locomotive power circuit.
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Isaicheva, A. G., M. V. Basharkin, A. L. Zolkin, A. N. Losev, and D. R. Giniyatullina. "Estimation of electrical energy losses in a DC traction rail network during heavy traffic." IOP Conference Series: Earth and Environmental Science 990, no. 1 (February 1, 2022): 012023. http://dx.doi.org/10.1088/1755-1315/990/1/012023.
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Abstract The growth of traction current leads to losses of electrical energy in the traction rail network, which entails losses for railway companies, including the Russian Railways holding. Additional losses arise due to the deterioration of the resistance of the elements, which occurs in a shorter time in terms of sections on which the movement of trains of increased mass and length is not carried out. Equations for estimation of the power and electrical energy losses in the DC traction rail network have been obtained. These equations are applicable both for the calculation at the sections of the circulation of freight trains, the mass of which does not exceed the weight norm established by the schedule on the route of this train, and taking into account the correction for the passage of long and heavy trains. A simulation model that makes it possible to assess the power losses in a section of a traction rail network depending on changes in the resistance of both individual elements and entire groups that make up the traction rail network, as well as to analyze the effect of the transition resistance rail-ground on the magnitude of leakage currents has been prepared. The need to constantly maintain the elements of the traction rail network in a working condition is determined. It is explained by a significant increase in losses in electrical energy when passing trains of increased weight and length, even with minor deviations of the resistance values from those established by the regulatory documentation. To maintain an operable state and reduce the likelihood of the appearance of faulty elements of the traction rail network, entailing the loss of electrical energy, it is proposed to develop automated monitoring systems for the traction rail network, which ensure the adoption of decisions on the need for maintenance or repair of an element of the traction rail network and transmit information about this repair personnel on duty.
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Ning, Wang Yun, Ying Chen, Yu Lan Kuang, and Yong Hua Zhang. "The Drag Reduction Mechanism of Vibration Digging Shovel." Applied Mechanics and Materials 288 (February 2013): 41–47. http://dx.doi.org/10.4028/www.scientific.net/amm.288.41.
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In order to investigate the drag reduction mechanisms of vibration digging shovel from the kinematics and mechanical aspects, and to estimate the magnitude of its traction resistance, we performed kinematic analysis when the velocity of the digging shovel was undergoing sinusoidal changes. Based on the analysis of the relationship between vibration direction angle, ascending direction angle and the edge motion curve, we evaluated the efficacy of different mining modes and proposed the ideal working conditions. We found that when the vibration direction angle φ <0 it could produce favorable cutting conditions. When the cutting direction angle θ was slightly less than or equal to the buried angle α and the ascending direction angle λ <π/2, the traction resistance was the least and soil-crushing effect was enhanced. The application of the moving viscous friction resistance model of mining shovel to analyze the force, including the impact of cutting speed on vibration viscous friction, could optimize the ideal working state and deduce the horizontal traction resistance formula of cutting and ascending. This model will be conducive to the structural design of vibration digging shovel and the estimation of its traction resistance.
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Nuriev, K. K., M. K. Nuriev, O. Rakhmatov, Sh Korabekova, and M. A. Bakhronova. "Determination of the total resistance of the ploughshare when the blade is blunted." IOP Conference Series: Earth and Environmental Science 1112, no. 1 (December 1, 2022): 012014. http://dx.doi.org/10.1088/1755-1315/1112/1/012014.
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Abstract The article notes that when plowing, the traction resistance of a ploughshare with an occipital chamfer increases in proportion to the volume of compacted soil. When working, the traction resistance of the ploughshare with the occipital chamfer increases in proportion to the volume of the compacted soil. It was revealed that with an increase in the angle of the occipital chamfer of 5 to 40 degrees, the traction resistance increases 11.3 times, Whereas with an increase in the width of the occipital chamfer from 0.5 mm to 4 mm, the traction resistance increases 60...64 times. For the longest operation of the ploughshare, it is necessary to develop such a technical solution for the ploughshare, during the operation of which an occipital chamfer with the largest dimensions, that is, with a minimum area, was formed from the back side. Then the pushing force of the ploughshare from the soil will have a minimum value, which will ensure the operation of the plough for the most maximum time without violating agrotechnical requirements for the depth of processing.
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Hu, Xiu Chi, Lan Xia Zheng, Lei Jia, and Xin Song. "Dynamic Simulation Tests on Influencing Factors of Deep Tilling Plow Working Performance." Advanced Materials Research 219-220 (March 2011): 441–45. http://dx.doi.org/10.4028/www.scientific.net/amr.219-220.441.
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A plow surface-soil system dynamic simulation model was established, through MathCAD and ANSYS/LS-DYNA, on which the dynamic simulation tests were carried out by experimental design method. The discipline and mechanism about forming parameters of guiding curve and the plow working factors influencing on two targets, traction resistance and turn performance, were discussed and the factors optimization was made. The results show that tangent angle of guiding curve endpoints has a remarkable influence on two targets; in addition, it is benefit for reducing traction resistance and enhancing turn performance when the angle is large. Under the optimal condition, traction resistance is 4.40kN and turn performance reaches the optimal level 8.0.
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Solomin, Vladimir A., Andrei V. Solomin, and Anastasia A. Chekhova. "Starting forces of the traction linear induction motor with adjustable resistance of the short-circuited winding of the secondary element." Transportation Systems and Technology 7, no. 2 (July 1, 2021): 87–96. http://dx.doi.org/10.17816/transsyst20217287-96.
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Background: Development and research of linear traction drives for Maglev transport is an urgent task. Linear induction motors can be used as traction machines for advanced rolling stock.
Aim: Study of the starting characteristics of an adjustable traction linear induction motor with variable resistance by a short-circuited winding of the secondary element.
Methods: Theoretically, relations were obtained for calculating the traction starting forces of an adjustable linear induction motor with various designs of a short-circuited winding of the secondary element.
Results: Based on the obtained ratios, the calculations of the starting traction forces of linear induction motors intended for use in promising modes of transport were performed.
Conclusion: The results of calculating the starting traction forces of adjustable linear induction motors make it possible to reasonably select the modes of starting the motor depending on the design of the secondary winding.
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Xin, Lili, Chuanqi Li, and Jihui Liang. "Study About the Design and Experiments of the Vibrating Resistance Reduction Force Measuring Device." Open Mechanical Engineering Journal 8, no. 1 (December 31, 2014): 705–9. http://dx.doi.org/10.2174/1874155x01408010705.
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The force measuring device is designed to the study of the relationship between vibration amplitude, frequency, speed and traction resistance of the tractor If the design of the force measuring device which consists of a force measuring frame and three octagonal ring transducers is successful, the goal of real-time monitoring of the traction resistance in the process of vibrating sub soil may be reached. Also, the up, down, left and right margin of frame is designed to be adjustable, so that different kinds of tractor could link up with the force measuring device. With the vibrating sub-soiler machine, the vibrating resistance reduction experiments, which are mainly based on the change of the vibration amplitude, frequency and the speed of the tractor, may be done. The three levels of the vibration amplitude, frequency, and speed are as follows: vibration amplitude: 0.001 m, 0.002 m, and 0.003 m; frequency: 9 Hz, 10 Hz, and 12 Hz; speed: 0.1 m/s, 0.2 m/s, and 0.3 m/s. The experiment results showed that with the same speed and bigger vibration frequency, the tractor traction resistance is small and when the amplitude is 0.001 m, the vibration frequency is 10 Hz, and forward speed is 0.2 m/s, and the tractor traction resistance is the minimum.
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Czarnecki, Jarosław, Marek Brennensthul, Włodzimierz Białczyk, Weronika Ptak, and Łukasz Gil. "Analysis of Traction Properties and Power of Wheels Used on Various Agricultural Soils." Agricultural Engineering 23, no. 1 (March 1, 2019): 13–23. http://dx.doi.org/10.1515/agriceng-2019-0002.
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AbstractThe paper presents results of the research on traction properties of two tractor tyres used on two agricultural grounds. The first ground was a stubble and the second one cropland. The investigated tyres had the same structure (diagonal, with a traditional tyre tread but different external dimensions. The research was carried out in field conditions with the use of a stand aggregated with a farm tractor. Analysis covered traction efficiency, slide, towing power and power lost on the rolling resistance and wheel slide. Based on the obtained results it was concluded that on a ground with lower compaction, the values of power losses were higher and traction efficiency was lower. Moreover, it was proved that the value of the power lost for rolling resistance had a decisive impact on the values of traction efficiency
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Wang, Yu Hua, Peng Yu Wang, and Guo Qing Zhang. "Based on LabVIEW Resistance Method Temperature Testing for Traction Transformers and Motor Winding." Advanced Materials Research 588-589 (November 2012): 488–91. http://dx.doi.org/10.4028/www.scientific.net/amr.588-589.488.
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Temperature is an important parameter for the characterization of the transformer and the motor running. Winding temperature test according to the actual operation of the traction transformer and motor temperature protection device requirements, in-depth study, temperature test of the traction transformer based on virtual instrument and traction motor winding resistance method, the method using LabVIEW to develop test software, respectively, for data acquisition, data playback, data analysis and processing, data file management functions, and temperature test equipment, not only real-time test system, but also post-processing the data after the test, in order to analysis of the factors that affect the temperature of the windings. Validity of the method is proved by experiments.
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Kosarev, A. B., R. A. Rudashevskiy, A. V. Rudashevskaya, P. I. Smolin, and I. A. Rebrov. "Determination of the rail-to-earth transition resistance of the ballastless track and influence of the resistance on the current spreading in the subgrade." Russian Railway Science 81, no. 1 (March 29, 2022): 7–15. http://dx.doi.org/10.21780/2223-9731-2022-81-1-7-15.
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Introduction. The rail-to-earth transition resistance is an important parameter of electrified railways, which directly effects the electrical safety level of the traction network and the potential distribution in the upper structure track area. The increased potential adversely effects the operation of the power supply system, the safety of passengers and service staff. Moreover, the mentioned potential leads to the insulation damage of the signaling equipment and to the threat of the train traffic security. The high-speed traffic development in Russia involves the ballastless track usage. The transition resistance of the ballastless track differs from that of a ballast track.Materials and methods. The article considers mathematical model of the ballastless track for determining the rail-toearth transition resistance. The authors presented a description of the method for rail-to-earth transition resistance with a known input resistance of the rail track, determined experimentally.Results. The paper demonstrates relative values of the voltage drop on the the ballastless track structural elements. The obtained data will be used to analyse and calculate the modes of operation of the traction power supply system that occur in the rail track during short circuits in the traction network, and to assess the electromagnetic compatibility of electrical installations.Discussion and conclusion. Obtained results will lead to study the transition resistance of the ballastless track concerning high short-circuit currents drainage from the rails by simulating a short circuit both near the traction substation and away from it.
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Figurnov, E. P., Yu I. Zharkov, and N. A. Popova. "Choosing the type of equivalent circuit of traction substation when calculating short-circuit currents in 25 kV power supply system." Vestnik of the Railway Research Institute 79, no. 3 (July 8, 2020): 139–44. http://dx.doi.org/10.21780/2223-9731-2020-79-3-139-144.
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When calculating short circuit currents in the traction network, it is necessary to take into account the input resistance of the traction substation, including the resistance of the transformers of the substation and the resistance of the power supply system. The input resistance during short circuit is determined based on the equivalent circuit of the external power supply system, of which this traction substation is an integral part. Traditionally equivalent circuit of a three-phase system has the form of a star, in which the resulting resistances in each phase are connected in series with a source of phase electromotive force, and these sources have a common point. Another equivalent circuit in the form of a triangle is possible, in which on each side the resulting resistances are connected in series with the source of linear electromotive force. It is important to note that neither one nor the other type of equivalent circuit is determined by the connection scheme of the transformer windings of the traction substation. It is only necessary to take into account the absence of a circuit for zero sequence currents. All elements of the equivalent circuit, as is known, should be brought to uniform basic conditions. If the parameters of these elements are expressed in named units, then the basic values are the effective voltage values of the main stage and the rated power of the power transformer of the traction substation. If the components of one and the other equivalent circuits are reduced to one stage of the operating voltage, for example 27.5 kV, then for the same elements of the power supply system, the resistance values in the equivalent circuit in the form of a triangle are three times larger than in the equivalent circuit in the form of a star. In this case, the input resistances of the traction substation for the one and the other equivalent circuits are absolutely identical. Therefore, in the calculation of short circuit currents of the traction network, you can use any of these equivalent circuits of the power supply system and traction substation. Formulas for calculating the resistances of the elements of the power supply system and electrical installations, given in the standards, manuals and reference books, relate to the equivalent circuit of the short circuit in the form of a star. When using an equivalent circuit in the form of a triangle, these resistances must first be tripled, and then divided by three when calculating the short-circuit currents. The meaninglessness of such an operation is obvious. The equivalent circuit of the traction substation and the external power supply system in the form of a triangle when calculating short circuits in the traction network has no advantages compared to the traditional equivalent circuit in the form of a star. The information on the linear currents on the primary and secondary windings of the traction substation transformer during a short circuit in the traction network is given, which is necessary to select the settings of its relay protection kit.
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Komaladewi, A. A. I. A. Sri, I. Gusti Agung Kade Suriadi, and I. Ketut Adi Atmika. "Geometric Progression Application in Design Transmission Gear Ratio." Applied Mechanics and Materials 776 (July 2015): 343–48. http://dx.doi.org/10.4028/www.scientific.net/amm.776.343.
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One of the important aspects in determining the competitiveness of an automotive product is the traction ability or performance, the vehicle's ability to accelerate, wind resistance, rolling resistance, against the force of the ramp, and the capacity to pull a load. The size of traction for any level of gear and vehicle speed that can be achieved can be controlled by adjusting the ratio and transmission rate. Transmission ratio affects the amount of torque that can be transmitted, while the number of speed levels affects the fineness of the process of transmission and transformation of power in the transmission system. To find a gear ratio between the lowest and highest transmission rate is by geometric progression. The basis of the use of this method is to get the ratio and amount of gear transmission rate of speed at the same engine operating speed so that fuel economy will be the same on each transmission. Modified gear ratio produce traction curve where the distance curve closer adjacent transmission. This indicates a loss of power transmission shifting is getting smaller or in other words the better traction performance. The design of the installation ratio 6-speed, generating traction curve with the distance between the curve near the sting traction, produces good traction or good performance.
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Gabaev, A. Kh. "Investigation of the driving resistance of a seeder with upgraded coulters." Izvestiya of Kabardino-Balkarian State Agrarian University named after V.M. Kokov, no. 2(36) (2022): 77–82. http://dx.doi.org/10.55196/2411-3492-2022-2-36-77-82.
Full textAbstract:
This paper presents the results of a study of the traction resistance of grain seeders with disc coulters with a zero angle of attack and hydrophobic furrow-forming pads. The change in the geometric dimensions of the working bodies, due to contact with the abrasive medium, is the main reason for the multiple increase in the value of traction resistance, laid down by the manufacturer. External factors affecting the increase in traction resistance of the machine are: climatic conditions in which the machine is operated, soil properties, quality of repairs and maintenance. The internal factors that cause a change in the characteristics originally set by the manufacturer are the imperfection of the design (the properties of the structural materials of the parts) and the technology of their manufacture. As the analysis of the condition of the seeding units shows, in a number of farms the discs of the sowing coulters are so worn out that their diameter is only 29-30 cm and even less, with a factory output of 35 cm. for sowing grain crops. The duration of operation of the sowing unit with factory performance depends on the properties of the soil, especially when working in difficult conditions, the loads on the working surfaces of the organs of agricultural machines increase by 1.5-3 times, and the number of failures increases sharply. The conducted studies of the modernized coulter with zero angle of attack show good performance with low traction resistance. The value of traction resistance at a stroke depth of 30 mm varied between 7-8.5 kg and 14- 16.8 kg at a coulter stroke depth of 60 mm. Which is 20-25% lower than that of serial double disc coulters.
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Pastushenko, S., M. Klendiy, and M. Klendiy. "EXPERIMENTAL HARROW WITH SCREW WORKING BODIES TRACTION RESISTANCE RESEARCH." Scientific bulletin of the Tavria State Agrotechnological University 10 (2020): 2. http://dx.doi.org/10.31388/2220-8674-2020-2-2.
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Hua, C., X. Gruz, and A. Ehrlacher. "Thin sand concrete plate of high resistance in traction." Materials and Structures 28, no. 9 (November 1995): 550–53. http://dx.doi.org/10.1007/bf02473160.
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