Academic literature on the topic 'Resistance maximale en traction'
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Journal articles on the topic "Resistance maximale en traction"
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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.
Dissertations / Theses on the topic "Resistance maximale en traction"
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Forestier, Jean-Paul. "Caracterisation de l'interface composite de collage / attaches orthodontiques." Paris 7, 1997. http://www.theses.fr/1997PA07GA03.
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Vieira, Eleno Rodrigues. "Reticulação peroxídica de compostos elastoméricos utilizados na indústria de pneus." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/108470.
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Compostos elastoméricos a base de borracha natural (NR) e copolímero de butadieno-estireno (SBR) utilizados na banda de rodagem de pneus são tradicionalmente reticulados com enxofre. O uso de peróxidos e co-agentes na reticulação desses compostos ainda é um desafio a se superar com relação às propriedades viscoelásticas requeridas, de extrema importância para um bom desempenho e vida útil dos pneus. Neste trabalho foi avaliado o uso de peróxidos sem e com co-agentes na reticulação de compostos NR/SBR com o intuito de avaliar a eficiência destes na manutenção das propriedades relevantes em relação a um composto tradicionalmente usado na confecção de banda de rodagem de pneus. Onze formulações com diferentes sistemas de reticulação foram preparadas, sendo uma de referência. Foram avaliadas propriedades físicas como dureza, densidade, tração, resistência ao rasgamento, resiliência, abrasão e DPC, e o comportamento dos compostos de NR/SBR com relação ao inchamento em tolueno. As propriedades dinâmicomecânicas dos compostos NR/SBR foram analisadas por DMA e RPA. Os compostos NR/SBR contendo somente peróxidos não apresentaram propriedades comparáveis ao composto de referência vulcanizado com enxofre. Os compostos contendo os sistemas peróxidos/co-agentes, BIS F 40 A-Retilink T40 (composto 10) e BIS F 40 A-Retilink TA 70 (composto 11) apresentaram os melhores resultados. O composto 10 e o composto de referência (composto 1) apresentaram valores similares de tan d a 60°C e tan d a 0°C (DMA), os quais estão correlacionados às propriedades de resistência ao rolamento e tração no molhado, respectivamente. Os resultados mostraram a possibilidade de uso de certos sistemas peróxido/co-agente em compostos de NR/SBR, em substituição ao sistema com enxofre, sem perda de propriedades, tendo como vantagem a redução de componentes na formulação, redução de tempo de processamento, e consequentemente custo da produção de bandas de rodagem.Rubber compounds based on natural rubber (NR) and styrene-butadiene rubber (SBR) used on tire tread are traditionally crosslinked with sulfur. The use of peroxides and co-agents in crosslinking of these compounds is still a challenge to be achieved, considering the required viscoelastic properties which are extremely important for a good tire performance and lifetime. In this work it was evaluated the use of peroxide systems with and without co-agents as crosslinking agents for NR/SBR compounds, with the aim of evaluating the efficiency of maintaining the key properties related to the traditionally used in the manufactory of tire tread. Eleven formulations with different systems were prepared, a one as a reference. Physical properties such as hardness, density, tensile strength, tear, resilience, abrasion and compression set and the behavior of NR/SBR compounds in relation of swelling Toluene were evaluated. The dynamic mechanical properties of the NR/SBR cured compounds were analysed by DMA and RPA. The NR/SBR compounds cured with only peroxide had poorer properties when compared to the reference compound vulcanized with sulfur. On the other hand, the compounds cured with proxide/co-agents, BIS F40 plus Retilink T40 (compound 10) or plus T70A (compound 11) showed better results.The compound 10 and the reference compound (compound 1) showed similar results of tan d 60 °C and tan d 0 °C (DMA), which are correlated to rolling resistance and wet traction, respectively. The results demonstrate the possibility of using a peroxide/co-agent as a cure system in NR/SBR compound instead of a sulfur-cured compound for tire tread applications, without the loss of desirable properties, lower processing times and consequently reducing manufacturing costs.
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IBOUCHICHENE, AICHE SMINA. "Contribution a la caracterisation rheologique du pmma-choc. - effets des vitesses de chargement et de la temperature sur la resistance mecanique en traction-." Paris, ENSAM, 1999. http://www.theses.fr/1999ENAM0011.
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L'objectif de ce travail est double : i) determiner l'evolution de la sensibilite mecanique du pmma-choc a la temperature et a la vitesse de deformation, ii) caracteriser l'endommagement genere dans ce materiau suite a une sollicitation de traction. Aux grandes deformations, les resultats obtenus lors de nos essais de traction a rupture du pmma-choc a differentes temperatures et vitesses de deformation ont montre une influence considerable de ces parametres sur le comportement global. Cette etude a permis d'identifier une transition du comportement ductile/fragile dans des conditions experimentales precises. Plus specialement, la sensibilite a la vitesse de deformation et a la temperature sur le seuil d'ecoulement nous a conduit a apprehender la nature des mecanismes elementaires qui, a l'echelle moleculaire, sont a l'origine du comportement macroscopique du pmma-choc. Les donnees recueillies a partir des mesures experimentales ont ete confrontees a un modele moleculaire decrivant les processus elementaires de la deformation en termes de mecanismes thermiquement actives. Ce modele est celui developpe par ree-eyring. Les resultats obtenus a partir de cette modelisation ont permis en se basant sur ceux issus d'une analyse viscoelastique de montrer que les mecanismes de deformation regissant le debut de la plasticite au seuil d'ecoulement sont aussi bien a la relaxation principale de la deformation de la phase elastomerique contenue dans les particules de renforcement du pmma-choc. La caracterisation l'endommagement a ete realisee par mesures mecaniques et une nouvelle technique d'essais interrompus a ete mise point. Elle offre en plus de sa facilite de realisation, un moyen de quantification de l'endommagement corrige des phenomenes structuraux. L'evolution du marqueur d'endommagement, mesure a travers cette technique, en fonction de la deformation definit une chronologie de l'endommagement pendant un essai de traction.
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Halfaoui, Saddek. "Contribution a l'etude de l'influence de la rugosite des subjectiles sur la resistance mecanique en traction et en fatigue de l'assemblage colle a simple recouvrement en sifflet." Paris 6, 1992. http://www.theses.fr/1992PA066502.
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Nous recherchons l'influence de l'etat de surface des subjectiles des substrats de l'assemblage colle a simple recouvrement en biseau, sur son comportement mecanique fin lorsqu'il est sollicite en traction simple et en fatigue par traction ondulee. Au cours de son endommagement, nous localisons, en utilisant simultanement l'extensometrie a jauges electriques et l'emission acoustique, l'amorcage, la croissance, le developpement des microfissures et des criques, tout le long du recouvrement et pendant toute la duree de vie de l'eprouvette. En appliquant plusieurs sables sur les subjectiles prealablement rectifies, nous avons defini la rugosite optimale pour laquelle les qualites de mouillabilite, et la resistance mecanique a la traction et a la fatigue sont les meilleures. Une analyse simplifiee du comportement elastique du joint a ete elaboree en faisant intervenir un correcteur d'extremite. Nos resultats montrent qu'il existe une adequation satisfaisante avec l'experience
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Vaziri, Mojgan. "Water Resistance of Scots Pine Joints Produced by Linear Friction Welding." Thesis, Nancy 1, 2011. http://www.theses.fr/2011NAN10059/document.
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Le soudage du bois est une technique d'assemblage sans adhésif de deux pièces de bois, leur soudure étant produite par friction mécanique sous pression des deux pièces. Ce procédé, applicable à des pièces de bois plates, d'essences identiques ou différentes, se prête à la fabrication de meubles et à la menuiserie. Cependant, le joint obtenu n'est pas de classe "extérieur", ce qui le réserve à un usage "intérieur". En effet, un joint destiné à une utilisation extérieure ou en milieu à humidité variable doit présenter une résistance élevée à l'eau. L'objectif principal de cette thèse est d'étudier la résistance à l'eau du bois soudé. A cet effet, des méthodes d'essais complémentaires et non-destructrices ont été utilisées, comme le scanner ou l'imagerie par résonance magnétique (IRM). L'influence des paramètres de soudage et des propriétés du bois sur, d'une part, la formation et la propagation des fissures dans la ligne de soudure, et sur, d'autre part, la densité et l'absorption d'eau de la soudure a été ainsi étudiée. Les expériences de cette thèse seront menées sur des échantillons de pin (Pinus sylvestris) de dimensions 200 mm x20 mm x 40 mm, coupés dans la direction longitudinale du fil du bois. La Norme Européenne EN 205 a servi de cadre pour déterminer la résistance des échantillons de pin en traction-cisaillement. Les méthodes d'essais (non-destructrices) ont été utilisées selon leur pertinence: le scanner a servi à étudier la formation et la propagation des fissures; l'imagerie par résonance magnétique (IRM) a permis quant à elle de caractériser la pénétration et l'infiltration d'eau dans le bois soudé.Le mécanisme d'adhérence du pin a été étudié grâce à la RMN MAS (spectrométrie à résonance magnétique nucléaire avec polarisation croisée et rotation à l?angle magique) du carbone13 et à la micro-densitométrie par rayons X. Ces différentes méthodes, non destructrices, offrent l'avantage d'une analyse non invasive et l'élimination de facteurs parasites liés à la préparation et à la coupe du bois. Voici en résumé les résultats obtenus les plus marquants: (1) Le scanner et l'imagerie par résonance magnétique (IRM) sont des méthodes de recherche particulièrement polyvalentes et adaptées à l'étude des bois soudés. (2) L'utilisation de bois de coeur, une pression de soudage de 1.3 Mpa et un temps de soudage de 1.5 s permettent d'augmenter la résistance à l'eau du pin soudé. (3) Des tests d'optimisation ont montré que la résistance du pin en traction-cisaillement est plus sensible aux variations de temps de soudage qu'au temps de refroidissement et qu'elle peut être optimisée à plus de 9.7 MPa en respectant une pression de 1.3 Mpa, un temps de soudage > 3.5 s et un temps de refroidissement < 60 s. (4) La résistance à l'eau du bois soudé peut être améliorée dans une certaine mesure en faisant varier paramètres de soudage et propriétés des essences, mais dans tous les cas, le recours à un imperméabilisant naturel et écologique reste nécessaire. (5) Le pin soudé possède une résistance à l'eau et en traction-cisaillement inhabituellement élevée, cela pouvant s'expliquer par une teneur en composés extractifs augmentée. (6) Des essais sous IRM ont montré que les causes de rupture du joint varient suivant l'essence: faible résistance à l'eau de la ligne de soudure dans le cas du hêtre soudé, retrait et expansion du bois dans le cas du pin soudé. (7) Les extractifs du pin améliorent nettement la résistance à l'eau du joint soudé, mais à un niveau qui ne lui permet cependant pas la certification "extérieur" sans protection. En revanche, il peut être certifié "semi-extérieur" avec protectionWood welding is a mechanical friction process allowing the assembly of timber without any adhesives. The process consists of applying mechanical friction, under pressure, alternately to the two wood surfaces to be welded. This process can be applied to weld two flat pieces of timber, originating from the same or different tree species, and can be used in the manufacture of furniture and wood joinery. The only limitation is that the joint is not exterior-grade, but only suitable for interior joints. Exterior use, or use in an environment with varying humidity demands water resistance of the welded joints. The main objective of this thesis is to study the water resistance of the welded wood. This is complemented with special attention to non-destructive test methods such as X-ray Computed Tomography (CT-) scanning and Magnetic Resolution Imaging (MRI). The influence of welding parameters and wood properties on crack formation and crack propagation in the weldline was investigated. The influence of these parameters on weldline density and water absorption in the weldline were also studied. Investigations in this thesis are based on welded samples of Scots pine (Pinus sylvestris) of the dimensions 200 mm × 20 mm × 40 mm which were cut in the longitudinal direction of the wood grain. The tensile-shear strength of the welded Scots pine samples were determined using European standard EN 205. Different non-destructive methods such as X-ray Computed Tomography (CT-) scanning to study crack formation and propagation, and magnetic Resolution Imaging (MRI) to characterize water penetration and the distribution mechanism in welded wood were used. Solid state CPMAS 13C NMR spectrometry and X-ray microdensitometry investigations were carried out to study the mechanism of adhesion in Scots pine. These various non-destructive methods offer the advantage of non-invasive analysis and the elimination of any artifacts present due to preparation and sectioning. The most important results are summarized as follows: (1) X-ray Computed Tomography (CT-) scanning and Magnetic Resolution Imaging (MRI) are versatile research methods applicable to investigations of welded woods. (2) Water resistance of welded Scots pine can be increased using heartwood, a welding pressure of 1.3 MPa, and a welding time of 1.5 s. (3) Optimization tests showed that the tensile-shear strength of Scots pine was more sensitive to welding time changes than holding time and could be optimized to more than 9.7 MPa using 1.3 MPa welding pressure, > 3.5 s welding time, and < 60 s holding time. (4) Changing welding parameters and wood properties can increase water resistance of welded wood to some extent, but treating the weldline with certain natural and environmentally-friendly water repellents is still necessary. (5) Welded Scots pine shows unusually high water resistance and tensile-shear strength. This may be explained by there being more extractives compounds in Scots pine. (6) MRI experiments showed that the origin of the joint failure in welded beech is poor water resistance of the weldline, while swelling and shrinkage of wood are the main reasons for joint failure of welded Scots pine. (7) Extractives in Scots pine dramatically improve water resistance of the welded joint, but not to a level to classify the joint as an unprotected exterior grade. However, it can qualify as a joint for protected semi-exterior application
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Palhari, Juliano. "Avaliação da resistência à tração de botões ortodônticos, com diferentes sistemas adesivos, com e sem contaminação com sangue." Universidade de Taubaté, 2007. http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=480.
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O objetivo do presente trabalho foi avaliar a resistência à tração de botões ortodônticos fixados em esmalte bovino, utilizando-se três sistemas adesivos, com e sem contaminação com sangue humano. Foram selecionados noventa incisivos bovinos nos quais foram fixados botões de aço inoxidável com base de 3,5 mm de diâmetro, utilizando-se os sistemas adesivos Magic Bond (Vigodent) e resina TPH (Dentisply), Fill Magic Ortodôntico (Vigodente) e adesivo Transbond Plus Self Etching Primer (3M) e resina TPH. Para cada sistema adesivo 15 espécimes foram colados após contaminação da área com sangue humano e 15 sem contaminação (controle), resultando em seis grupos. Após colagem, os botões foram submetidos a ensaios de tração até deslocamento do mesmo e os resultados foram transformados para MPa. Os dados obtidos foram analisados estatisticamente (p 0,05) utilizando análise de variância a um critério (ANOVA) e teste de Tuckey. Para comparar os grupos contaminados com sangue com os controles utilizou-se Teste t de Student. A resistência à tração obtida (MPa), considerando-se os valores encontrados nos grupos estudados ocorreram na seguinte ordem: Adesivo Transbond Plus Self Etching Primer e resina TPH sem (2,66 1,41) e com contaminação (2,29 1,11); Adesivo Magic Bond e resina TPH sem (2,23 0,94) e com contaminação (1,68 0,78); e, Adesivo Fill Magic Ortodôntico sem (1,20 0,34) e com contaminação (0,51 0,37). Houve maior resistência à tração nos botões fixados sem contaminação e ocorreram diferenças estatisticamente significantes entre os diferentes sistemas
adesivos utilizados.The objective of this work was to evaluate the tensile strenght of orthodontic buttons settled in bovine enamel, using three systems adhesive, with and without contamination with human blood. Ninety bovine incisors had been selected in which stainless steel buttons had been fixed with base of the 3,5 mm of diameter, using themselves adhesive systems Magic Bond (Vigodent) and resin TPH (Dentisply), Fill Magic Ortoodôntico (Vigodente) and adhesive Transbond Plus Self Etching Primer (3M) and resin TPH. For each adhesive system 15 specimens had been glue after contamination of the area with human blood and 15 without contamination (control), resulting in six groups. After glue, the buttons had been submitted the assays tractive until displacement of the same and the results had been transformed for MPa. The gotten data had been analyzed for statistics (p 0,05) using analysis of variance to a criterion (ANOVA) and test of Tuckey. To compare the groups contaminated with blood with the controls Test t of Student was used. The tensile strenght gotten (MPa), considering the values found in the studied groups had occurred in the following order: Adhesive Transbond Plus Self Etching Primer and resin TPH without (2,66 1.41) and with contamination (2,29 1.11); Adhesive Magic Bond and resin TPH without (2,23 0,94) and with contamination (1,68 0,78); e, Adhesive Fill Magic Orthodôntico without (1,20 0,34) and with contamination (0.51 0,37). It had greater tensile strenght in the buttons settled without contamination and had occurred significant statistics differences between the different used adhesive systems.
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Солових, Є. К., А. А. Тихий, С. Є. Катеринич, Y. Solovykh, A. Tykhyi, and S. Katerynych. "Вплив реологічних властивостей, прилеглого до різального елементу робочого органу шару ґрунту, на механізм його обробітку." Thesis, Baltija Pubiishing, 2017. http://dspace.kntu.kr.ua/jspui/handle/123456789/7739.
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У реології ґрунтів в якості фундаментальних властивостей розглядають: пружність; пластичність і в'язкість. Усі інші механічні властивості є складним поєднанням різних комбінацій цих трьох фундаментальних властивостей. Для дослідження механічних властивостей і мікроструктури ґрунту останнім часом стали активно застосовуватися реологічні методи. Вони дозволяють отримати ряд кількісних фізично обґрунтованих параметрів, з допомогою яких стає можливим прогнозувати зміну мікроструктури ґрунту при навантаженнях. Сучасні прилади дозволяють значно збільшити точність вимірювання реологічних параметрів і їх кількість. Реометри є високочутливими приладами для вимірювання взаємодії між частинками ґрунту в оброблюваному шарі. Застосування реометру для вивчення мікроструктури показана у великому ряді робіт. Для дослідження в'язкопружних властивостей чорнозему використано метод амплітудної розгортки з вимірювальною системою паралельних плато на модульному реометрі MCR-302.
In the soil's rheology, fundamental properties are considered: elasticity; ductility and viscosity. All other mechanical properties are a complex combination of various combinations of these three fundamental properties. To study the mechanical properties and microstructure of the soil, lately, rheological methods have become actively used. They allow to obtain a number of quantitatively physically grounded parameters, by which it becomes possible to predict the change of soil microstructure under loads. Modern devices allow to significantly increase the accuracy of measurement of rheological parameters and their number. Rheometers are highly sensitive devices for measuring the interaction between soil particles in the treated layer. The use of the rheometer to study the microstructure is shown in a large number of papers. To study the viscoelastic properties of soil, the method of amplitude scanning with the measuring system of parallel plateau on the modular rheometer MCR-302 is used.
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XIAO, JIAYU. "Etude de la prevision de la resistance a la rupture et des mecanismes d'endommagement en traction monotone et cyclique des stratifies composites non tisses et tisses contenant des trous circulaires." Paris, CNAM, 1992. http://www.theses.fr/1992CNAM0142.
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Cette these a utilise les criteres de whitney et nuismer, de pipes, et les modeles de tan et de degradation progressive par calcul aux elements finis (mdpc) pour etudier la resistance et le mecanisme d'endommagement de plusieurs types de plaques stratifiees portant des trous circulaires en traction monotone. Le comportement de fatigue en traction de trois stratifies tisses a egalement ete aborde. L'attention a ete principalement concentree sur la chute de rigidite secante. L'apparition et l'evolution des endommagements au fur et a mesure du nombre de cycles. Les tractions monotone et cyclique, radiographie, emission acoustique et microscopie ont ete adoptes pour verifier les resultats prevus et pour avoir le detail des mecanismes de l'endommagement au sein des materiaux composites non tisses et tisses. Les resultats dans le cas monotone montrent: les criteres utilises sont assez precis et simples a utiliser; les modeles de tan modifies dans cette these sont preferables pour les stratifies tisses et orthotropes et ces modeles peuvent donner des informations sur l'endommagement; le mdpc est preferable pour savoir le suivi d'endommagement; le mecanisme de l'endommagement dans le cas tisse est plus complexe que celui dans le cas non tisse. Les resultats dans le cas cyclique montrent: la courbe rationalisee de la chute de rigidite peut se diviser en trois stades; l'apparition et la propagation des endommagements observables se produisent pendant le troisieme stade et ces endommagements sont orientes de preference suivant les plis a 90; la propagation peut aussi se diviser en trois stades, dont un stade stable, un stade instable et un stade brutal; la tenue en fatigue des materiaux est principalement dominee par le stade stable pendant la propagation; la vitesse de l'evolution des endommagements est influencee par les sequences d'empilement; il existe un seuil de distance sur le ligament et un seuil de duree de vie au-dessus desquels la rupture catastrophique se produit
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Hakem, Naoual. "Etude de l'interaction des dommages de fatigue et de deformation progressive : effet d'un chargement primaire (entraction) sur la resistance a la fatigue oligocyclique en torsion de l'acier 304l a temperature ambiante." Paris 6, 1987. http://www.theses.fr/1987PA066422.
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Etude experimentale sur des eprouvettes tubulaires minces soumises a une variation cyclique d'un angle de torsion sur laquelle est superposee une contrainte de traction constante. Determination d'une courbe de resistance a la fatigue pour chaque niveau de chargement primaire. L'effet du chargement primaire conduit, a une reduction sensible du terme d'endurance dans l'equation de resistance a la fatigue. La rupture a lieu par fatigue et non par deformation, plastique excessive. Analyse de la reduction de la duree de vie associee a l'application d'un changement primaire
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Fanton, Fabrício. "Análise de estruturas aeronáuticas reforçadas por doublers colados." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265083.
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Orientador: Paulo SolleroDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
Made available in DSpace on 2018-08-21T04:28:57Z (GMT). No. of bitstreams: 1 Fanton_Fabricio_M.pdf: 34307939 bytes, checksum: 90121f68d41d617f120ccb7aab340d41 (MD5) Previous issue date: 2012
Resumo: Na indústria aeronáutica o uso de juntas coladas, rebitadas, parafusadas e soldadas na união de partes estruturais é de extrema importância no projeto das aeronaves. No entanto, devido as suas vantagens, as juntas coladas representam uma das principais tecnologias disponíveis para a exploração de novos materiais e para o desenvolvimento de projetos inovadores de configurações estruturais. Atualmente muitas aplicações aeronáuticas de colagem estão em estruturas e peças secundárias, contudo esta tecnologia apresenta grandes potenciais que dependem de um processo robusto e do domínio do dimensionamento e certificação. A colagem de chapas adicionais, chamadas de doublers, em áreas mais críticas de fuselagem e asa conduz à redução de usinagem química e mecânica, provendo um melhor aproveitamento dos materiais. Portanto, o doubler colado é uma alternativa de junta bastante eficaz em substituição às outras alternativas presentes hoje na indústria aeronáutica, promovendo uma maior eficiência na transferência de carga, potencial de redução de custo, alta resistência à corrosão e à fadiga, característica de retardar a propagação de trincas e maior integração das peças. Desta maneira, este trabalho tem como objetivo estudar estruturas aeronáuticas metálicas reforçadas por doublers colados, usando modelos analíticos, numéricos e experimentais, com ênfase na análise de tensões do adesivo. Além disso, criou-se um software com interface amigável reunindo os modelos analíticos mais importantes na análise de doublers colados e o modelo analítico criado pelo autor deste trabalho, permitindo a comparação das tensões no adesivo com os modelos numéricos. Na parte experimental, por tratar-se de um estudo relativamente novo e sem normalização específica de ensaios disponíveis, foram desenvolvidas técnicas de análise com o uso do processamento digital de imagens e da extensometria, além do projeto dos corpos de prova. Foram também projetados e ensaiados subcomponentes utilizados para simular as aplicações reais de doublers colados, através do desenvolvimento de uma ferramenta de otimização paramétrica visando à redução do peso nas aeronaves
Abstract: In the aircraft industry the use of bonded, riveted, bolted and welded joints at the junction of structural parts are extremely important in aircraft design. However, due their advantages, bonded joints, represent one of the main technologies available for the exploration of new materials and to the development of innovative structural configurations. Nowadays several aircraft bonded applications are applied in structures and secondary parts, however, this kind of technology presents a huge potential that depends on a robust model, in an effective sizing process and in an accurate certification. The bonding process of additional plates, best-known as doublers, in critical fuselage areas and in wings lead to a reduction in chemical and mechanical machining, providing a better material use. Thus, to avoid chemical milling, in some critical areas of the fuselage, are installed additional plates. These plates are called doublers, and are bonded in the base plate as a reinforcement located to reduce the stress level. Therefore, the use of bonded doublers is a very effective alternative to replace other alternatives present today in the aviation industry, promoting greater efficiency in load transfer, lower cost, high corrosion resistance, lower crack propagation and greater integration of parts. Thus, this work aims to study aeronautical metal structural joints reinforced by bonded doublers, through the analysis by analytical, numerical and experimental models, with emphasis on stress analysis of adhesive. In addition, software was created with a friendly interface gathering the most important analytical models in the analysis of bonded doublers, and allowing within this software to make the comparison with numerical models. Due the lack of standard tests and its relatively new study, new proceedings were created. These techniques were developed by the use of digital image processing and strain gage. Several subcomponents were designed and tested to simulate the actual application of bonded doublers, through the development of an optimization process in order to reduce weight of the aircraft
Mestrado
Mecanica dos Sólidos e Projeto Mecanico
Mestre em Engenharia Mecânica
Books on the topic "Resistance maximale en traction"
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G, Pottinger Marion, Yager Thomas J, ASTM Committee E-17 on Traveled Surface Characteristics., and ASTM Committee on F-9 on Tires., eds. The Tire pavement interface: A symposium. Philadelphia, PA: ASTM, 1986.
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Joint Winter Runway Friction Measurement Program. Overview of the Joint Winter Runway Friction Measurement Program. [Montréal]: Transportation Development Centre, 2004.
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Mortimer, Sarah. Reformation, Resistance, and Reason of State (1517-1625). Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780199674886.001.0001.
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The period 1517–1625 was crucial for the development of political thought. During this time of expanding empires, religious upheaval, and social change, new ideas about the organization and purpose of human communities began to be debated. In particular, there was a concern to understand the political or civil community as bounded, limited in geographical terms and with its own particular structures, characteristics, and history. There was also a growing focus, in the wake of the Reformation, on civil or political authority as distinct from the church or religious authority. To explain these new ideas about political power, the concept of sovereignty began to be used, alongside a new language of reason of state. Yet political theories based upon religion still maintained significant traction, particularly claims for the divine right of kings. In the midst of these developments, the language of natural law became increasingly important as a means of legitimizing political power; natural law provided a rationale for earthly authority that was separate from Christianity and its use enabled new arguments for religious toleration. This book offers a new reading of early modern political thought, drawing on a wide range of sources from Europe and beyond. It makes connections between Christian Europe and the Muslim societies that lay to its south and east, showing the extent to which concerns about the legitimacy of political power were shared. It demonstrates that the history of political thought can both benefit from, and remain distinctive within, the wider field of intellectual history.
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Miller, Shae. Sexuality, Gender Identity, Fluidity, and Embodiment. Edited by Holly J. McCammon, Verta Taylor, Jo Reger, and Rachel L. Einwohner. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780190204204.013.13.
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Social movement activists have frequently used a variety of embodied tactics to negotiate cultural conceptions of gender and sexuality, which are in constant flux. This chapter attends to the ways that new social formations of gender and sexuality—including the recent emphases on gender and sexual fluidity—have impacted the politics, goals, tactics, and identities of contemporary women’s movements. Incorporating queer, transgender, critical race, and disability studies, this chapter emphasizes the ways that women seeking to attain gender and sexual justice have used the body both as a site of everyday resistance against repressive gender and sexual norms and as a tool for performing overt political protests. It illustrates how gender and sexual fluidity have gained new traction within social movements and discusses the implications for conceptualizing women’s activism.
Book chapters on the topic "Resistance maximale en traction"
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Páez Moreno, Diego Fernando, and Jeniffer Hamón Caicedo. "Traction Resistance in Chemical Anchors Resistencia a Tracción En Anclajes Químicos." In Lecture Notes in Civil Engineering, 755–63. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-90788-4_58.
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Solovyov, Sergey, Vladimir Zhigulsky, and Inna Sulak. "Determination of the Traction Resistance of the Loosening Share of the Combined Working Body for Non-moldboard Tillage." In XV International Scientific Conference “INTERAGROMASH 2022”, 547–54. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-21432-5_57.
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Borstelmann, Thomas. "Resistance to the New Hyper-Individualism." In The 1970s. Princeton University Press, 2011. http://dx.doi.org/10.23943/princeton/9780691141565.003.0006.
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This chapter explores the resistance to the new hyper-individualism of the decade. It shows that not everyone found comfort in the increasingly though not fully entwined enthusiasms for greater human equality and the marketplace that took shape in the 1970s. An unfettered individualism, with all progressively more welcome to participate as autonomous buyers and sellers, was emerging as the central feature of contemporary American culture and gaining traction around the globe, but it deeply troubled certain observers. Some of the objections came from predictable if diverse corners. Socialist revolutionaries from Vietnam to Angola to Nicaragua, for example, saluted equality, at least in principle, but rejected the market and restricted private property. They fought for a collectivist future that they believed would offer greater justice and less exploitation, but it was a fight they clearly would be losing within a decade.
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"BÉTON DE SABLE DE HAUTE RESISTANCE EN TRACTION (High strength sand concrete in tension)." In Special Concretes - Workability and Mixing, 171–80. CRC Press, 1993. http://dx.doi.org/10.1201/9781482271379-28.
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Sandidzadeh, Mohammad Ali, Amir Ebrahimi, and Amir Heydari. "Fuzzy Direct Torque-controlled Induction Motor Drives for Traction with Neural Compensation of Stator Resistance." In Induction Motors - Applications, Control and Fault Diagnostics. InTech, 2015. http://dx.doi.org/10.5772/61545.
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Tojiddin Khayrullaevich, Juraev, Norov Sobirjon Negmurodovich, and Musulmanov Furqat Shodiyevich. "Study of the Parameters of the Planner with a Screw Working Body." In Direct Torque Control Strategies of Electrical Machines [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.93308.
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This chapter examined the theoretical background of the use of a screw working body in front of the planner bucket and conducting experiments in laboratory conditions with the proposed working body. This work supports the practical solution of using a screw working particle in the current field planning. Significance of the work reducing traction resistance to soil movement up to 20% enables the tractor unit to work at higher speeds of translational motion; the latter contributes to increased productivity, improved planning quality and reduced cash costs per unit of work performed. The chapter was prepared under results of research in the Mechanics Laboratory of Bukhara Engineering Technological Institute.
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Nelson, William E. "Ready Acceptance of the Common Law: Pennsylvania, New Jersey, and the South." In E Pluribus Unum, 90–105. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780190880804.003.0007.
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William Penn and the Quakers who had earlier settled West Jersey appear to have understood, as had Lord Baltimore a half century earlier in Maryland, that the common law provided the best possible protection of property rights and that protecting the property of Quaker settlers was the best means of protecting their religious freedom. Accordingly, both Pennsylvania and West Jersey adopted the common law at their first settlement. East Jersey Puritans interposed some resistance to the common law, but the colony gradually adopted it as it gained traction in neighboring New York. All colonies south of Virginia received the common law at their founding.
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"Evaluation of the cohesion of bitumen mixtures by means of the indirect traction resistance tests U.BONVINO Road and Transport Department, Bari University, Italy." In Mechanical Tests for Bituminous Mixes - Characterization, Design and Quality Control, 101–20. CRC Press, 1990. http://dx.doi.org/10.1201/9781482267518-14.
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Ellis, Katharine. "The National Conservatoire System." In French Musical Life, 33–70. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780197600160.003.0002.
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Discussion of the educational situation in Paris prepares the main arguments of chapters 1 and 2 in relation to nationalized and independent conservatoires in the provinces. Here, the soft power of the state-financed Paris Conservatoire (founded 1795) is contrasted with the more haphazard attempts of the privately funded Schola Cantorum (founded 1896) to act as a centralizing force. After the Revolution the cathedral choir school (maîtrise) system was initially replaced by the Paris Conservatoire alone, but the need for a deconcentrated national system of succursales was keenly felt. However, the Paris Conservatoire’s pedagogical approach could not immediately be imposed on provincial institutions, and some municipalities guarded their independence. A mixed economy of resistance and compliance resulted in a general trend towards homogenization (unity in uniformity) but more decentralist variety and ambition than the government ministry overseeing them found ideal. The Schola Cantorum showed similar centralizing tendencies but could not achieve significant institutional traction.
Conference papers on the topic "Resistance maximale en traction"
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Bulgakov, Volodymyr, Semjons Ivanovs, Valerii Adamchuk, Volodymyr Nadykto, Anatoliy Zaryshnyak, Vadym Yaremenko, and Liudmyla Krasiuk. "Influence of tractor hitch linkage system on plowing unit performance." In 22nd International Scientific Conference Engineering for Rural Development. Latvia University of Life Sciences and Technologies, Faculty of Engineering, 2023. http://dx.doi.org/10.22616/erdev.2023.22.tf111.
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The quality indicators of the ploughing unit largely depend on the joining diagram of the mounted plough with the tractor. Most often, this joining, performed according to a two-point or three-point diagram, is asymmetric. As a result, momentum arises that tries to turn the tractor in a horizontal plane. Depending on the chosen diagram for joining the tractor with a mounted plough, this momentum will be greater or less, and the performance of the ploughing unit will be worse or better. This paper evaluates the dependence of the momentum value on the plough rotation angle and the asymmetry of its joining to the tractor with two-point and three-point diagrams for adjusting the rear hitch linkage system. Calculations have established that the increase in the specified momentum occurs more intensively with a two-point diagram for joining the plough to the tractor. In this regard, its use is advisable only for specific ratios between the plough width and the parameters of the tractor running system. At the same time, with a certain adjustment of the tractor’s rear hitch linkage system according to the three-point diagram, it is possible to achieve such a position when its centre of mass practically coincides with the point of the plough traction resistance application. Ultimately, this ensures the momentum value is reduced to a minimum (almost zero) value. Experimental studies have established, when setting the convergence angle of the lower links of the tractor hitch linkage system according to the three-point diagram at the level of 0.49 rad, the null hypothesis about the equality of the plough operating width variances in comparison with the option of its joining according to the two-point diagram does not deviate. The frequency distributions of the plough rotation angle oscillations (𝛽) are also almost identical. The maxima of the normalized spectral densities of the parameter 𝛽 oscillations fall on the same frequency equal to 0.1 s-1. The oscillation variances of the angle β for both plough joining diagrams are concentrated in the same range of rather low frequencies: 0-1.0 s-1, i.e. 0-0.16 Hz.
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Shang, Zhan, Xiaofeng Yang, Jingda Gu, and Trillion Q. Zheng. "Modeling of Negative Resistance Converter Traction Power System." In 2020 IEEE Energy Conversion Congress and Exposition (ECCE). IEEE, 2020. http://dx.doi.org/10.1109/ecce44975.2020.9236360.
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Gyftakis, K. N., P. A. Panagiotou, N. Lophitis, D. A. Howey, and M. D. McCulloch. "Breakdown resistance analysis of traction motor winding insulation under thermal ageing." In 2017 IEEE Energy Conversion Congress and Exposition (ECCE). IEEE, 2017. http://dx.doi.org/10.1109/ecce.2017.8096964.
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D., Melnikov, Tsarev A., and Ignatenko I. "STUDY OF THE TRACTION RESISTANCE OF THE SPHERODIS COWLER AT STRIP SEEDING." In Innovative technologies In science and education. DSTU-Print, 2019. http://dx.doi.org/10.23947/itno.2019.232-235.
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Otero Yugat, Jesu´s, and Igor Alonso Portillo. "Experimental Evaluation of Resistance to Motion of a Light Rail Vehicle." In ASME 2011 Rail Transportation Division Fall Technical Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/rtdf2011-67023.
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All railway vehicles running on a track have to overcome a resistance to motion. The resistance to motion is due to mechanical and electrical losses, as well as to aerodynamic drag. In order to evaluate this resistance, two different experimental methodologies can be used. The first one consists on a conventional method which takes into account the energy stored in rotating masses and the equivalent curving and grade resistance. The application of this method is based on a coasting test procedure done on a straight track without slope. The second methodology consists on the experimental acquisition of electrical signals in the traction power line and strain measurements at the traction links of the bogie-truck, with different speeds. The electrical signals allow obtaining the efficiencies of the equipments in the traction power line. Once the different efficiencies of the equipments in the traction power line are known, the power transmitted to each wheel can be determined and consequently the resistance to motion is calculated. This paper summarizes an experimental procedure based on both methodologies. The designed instrumentation uses voltage and current probes for the recording of electrical signals in the traction line, piezorresistive accelerometers in order to obtain the uncompensated and the longitudinal accelerations of the train, extensometric gauges in full bridge configuration for the acquisition of stresses at the traction links, and a gyroscope for the detection of curves along the track. Several tests have been done by means of the described methods in light rail vehicles. Also, the vehicles have been tested in order to evaluate the influence of the air conditioning and air intakes, the circulation in curves and the cooling of traction equipments in the resistance to motion. Through these experimental methods, a useful tool for the prediction and analysis of the resistance to motion is provided. Additionally, the results obtained by means of these methodologies permit to calculate the influence of different running conditions in the resistance to motion.
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Mapelli, F. L., A. Bezzolato, and D. Tarsitano. "A rotor resistance MRAS estimator for induction motor traction drive for electrical vehicles." In 2012 XXth International Conference on Electrical Machines (ICEM). IEEE, 2012. http://dx.doi.org/10.1109/icelmach.2012.6349972.
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Yu, Haoyuan, Wei Liu, and Peipei Wang. "Research on stray current and rail-to-earth resistance in traction supply system." In 2017 IEEE Transportation Electrification Conference and Expo, Asia-Pacific (ITEC Asia-Pacific). IEEE, 2017. http://dx.doi.org/10.1109/itec-ap.2017.8080767.
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Lieh, Junghsen. "Analytical Traction and Propulsion Analysis." In ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/dsc-24522.
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Abstract Conventional approach for vehicle traction and propulsion analysis used spreadsheets. This is inconvenient if one intends to vary a parameter, and it is even more difficult when multiple parameters are evaluated at the design phase. In this paper, it is intended to formulate two nonlinear differential equations representing road load and power consumption. By expanding inertia force, air drag, rolling resistance, gravitational force and tire tractive force, the equations can be simplified as the function of velocity v, i.e., s 1 v ˙ = s 2 - s 3 v 2 and m v ˙ = - r 1 v 3 - r 2 v + r 3 v , respectively. With these two equations, it allows engineers to use either numerical or analytical method to study key parameters at the design phase. To demonstrate the effectiveness of these equations, Wright State’s electric car model is used. The results for front-wheel drive (FWD), rear-wheel drive (RWD) and four-wheel drive (4WD) cases are presented.
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Bachman, L. Joseph, and James McIntyre. "Snow Traction Performance of Low Rolling Resistance Drive Tires for Class-8 Tractor Trailers." In SAE 2012 Commercial Vehicle Engineering Congress. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2012. http://dx.doi.org/10.4271/2012-01-1918.
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Eui-Chun, Lee, Soon-O. Kwon, and Hong Jung Pyo. "Thermal and Electrical Characteristics of EV Traction Motor Considering AC Resistance of MSO Coil." In 2018 IEEE Transportation Electrification Conference and Expo (ITEC). IEEE, 2018. http://dx.doi.org/10.1109/itec.2018.8450167.
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