Results 31 to 40 of about 1,461,299 (208)
Witt equivalence of function fields of conics [PDF]
Algebra and Discrete Mathematics, 2020 Two fields are Witt equivalent if, roughly speaking, they have the same quadratic form theory. Formally, that is to say that their Witt rings of symmetric bilinear forms are isomorphic. This equivalence is well understood only in a few rather specific classes of fields.
Gladki, P., Marshall, M.
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SOME EQUIVALENT CONDITIONS FOR CONIC SECTIONS [PDF]
The Pure and Applied Mathematics, 2012 Let A and B denote a point, a line or a circle, respectively. For a positive constant a, we examine the locus CAB(a) of points P whose distances from A and B are, respectively, in a constant ratio a. As a result, we establish some equivalent conditions for conic sections. As a byproduct, we give an easy way to plot points of conic sections exactly by a
Dong-Soo Kim +6 more
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R-equivalence on conic bundles of degree 4
Duke Mathematical Journal, 1987 Dans la classification d'Enriques-Manin-Iskovskih [\textit{V. A. Iskovskih}, Math. USSR, Izv. 14, 17--39 (1980); translation from Izv. Akad. Nauk SSSR, Ser. Mat. 43, 19--43 (1979; Zbl 0412.14012)] des surfaces rationnelles définies sur un corps \(k\), les surfaces fibrées en coniques au-dessus de la droite projective \(\mathbb{P}^1_k\) et qui possèdent
Colliot-Thélène, J.-L. +1 more
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Wheel Profile Optimization of Speed-up Freight Train Based on Multi-population Genetic Algorithm
, 2021 The geometric shape of the wheel tread is mathematically expressed, and geometric parameters affecting the shape of the wheel were extracted as design variables.
FU, Yaodong +4 more
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Rail Geometry Analysis (From the Point of View of Wearing in the Operation)
Communications, 2003 Rail geometry analysis is, from the point of view of wearing in the operation, the question of present railway vehicles operation practice. The sequels of negative influence are reflected on the environment state.
Juraj Gerlici, Tomas Lack
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Applied Sciences, 2023 Turnouts are the weak spot in high-speed rail systems, and it is simple for the phenomenon of the wheel–rail force and the carbody lateral acceleration over-limit to arise when the train passes through, which affects the service life of the rail and the ...
Qian Xiao +3 more
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Research on Influence of Equivalent Conicity on Lateral Stability of 120 km/h Metro Vehicles
机车电传动, 2020 Based on the fact that 120 km/h B-type metro vehicles had a large wheel equivalent conicity in actual operation, a multi-body dynamic model of the vehicle was established with Simpack dynamic simulation software, which could restore the abnormal ...
Hao LI +4 more
doaj
The equivalent diameter of conical nozzle in Hagena scaling laws
Acta Physica Sinica, 2013 The cluster size is an important parameter in the study on the interaction of intense laser pulse with cluster jet produced by the gas adiabatic expansion through a nozzle into vacuum. The Hagena scaling law is usually used to estimate the average cluster size.
Chen, GL +7 more
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SuFEx‐Enabled Reprogramming of Flavonoids for Selective α‐Glucosidase Covalent Inhibition
Advanced Science, EarlyView.Selective inhibition of intestinal α‐glucosidase remains limited by poor enzyme specificity and off‐target metabolic effects. Here, SuFEx click chemistry is used to reprogram natural flavonoids into covalent inhibitors with enhanced α‐glucosidase selectivity and controlled reactivity. This strategy enables effective regulation of carbohydrate digestion
Fengyu Guo +14 more
wiley +1 more source
Analysis of wheel wear characteristics of high-speed train based on field data
Nihon Kikai Gakkai ronbunshu, 2019 A wheel/rail profile wear is a factor that affects the behavior of railway vehicles such as riding comfort, running stability, running safety and maintenance schedule.
Satoshi HARA +2 more
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