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241.
J.A.C. Martins M.D.P. Monteiro Marques 《Journal of Mathematical Analysis and Applications》2008,343(2):1007-1021
This paper discusses the stability of quasi-static paths for a continuous elastic-plastic system with hardening in a one-dimensional (bar) domain. Mathematical formulations, as well as existence and uniqueness results for dynamic and quasi-static problems involving elastic-plastic systems with linear kinematic hardening are recalled in the paper. The concept of stability of quasi-static paths used here is essentially a continuity property of the system dynamic solutions relatively to the quasi-static ones, when (as in Lyapunov stability) the size of initial perturbations is decreased and the rate of application of the forces (which plays the role of the small parameter in singular perturbation problems) is also decreased to 0. The stability of the quasi-static paths of these elastic-plastic systems is the main result proved in the paper. 相似文献
242.
M. Pisarek P. Kędzierzawski M. Janik-Czachor K. J. Kurzydłowski 《Journal of Solid State Electrochemistry》2009,13(2):283-291
The stability of the passive film formed on austenitic 303 stainless steel in the as-received state and after severe plastic
deformation by hydrostatic extrusion (HE) leading to nanostructurization was investigated in an aggressive environment containing
Cl− ions by anodic polarization. Transmission electron microscopy (TEM) and stereological image analysis were used to examine
structural changes introduced by HE. Surface analytical techniques such as light microscopy, scanning electron microscopy,
Auger electron spectroscopy (AES), and scanning Auger microscopy (SAM) were used to characterize the morphology, grain size,
and chemistry of the surface, including local characterization of nonmetallic inclusions and their surface before and after
HE. SAM analysis revealed discontinuities of the passive oxide film on MnS inclusions. TEM and scanning transmission electron
microscopy examinations confirm a drastic reduction of grain size accompanied by a distinct refinement of the size of sulfide
inclusions in the HE matrix. These changes in the HE 303 stainless steel are apparently responsible for its reduced pitting
resistance compared to the as-received material.
Contribution to the Fall Meeting of the European Materials Research Society, Symposium D: 9th International Symposium on Electrochemical–Chemical
Reactivity of Metastable Materials, Warsaw, 17th–21st September, 2007. 相似文献
243.
244.
《Optimization》2012,61(4):531-536
A general framework to the over-relaxed proximal point algorithm based on H-maximal monotonicity is introduced, and then it is applied to the approximation solvability of a general class of nonlinear inclusion problems based on the generalized resolvent operator technique. This form of the proximal point algorithm seems to be more application-oriented to inclusion problems. 相似文献
245.
In order to obtain full information coverage on melt inclusions in Martian meteorites (subgroup nakhlites) complementary micro-analytical techniques were used, i.e. focused ion beam, transmission electron microscopy and laser ablation. Using focused ion beam several lamellae for transmission electron microscopy were prepared and secondary electron images of cross-sections could be acquired. Laser ablation–inductively coupled plasma mass spectrometry analyses were performed on selected inclusions to obtain mass-oriented bulk composition of inclusions at depth. The differences in composition between melt inclusions in olivine and augite crystals would suggest a xenocrystic origin for olivine. Furthermore, electron diffraction patterns clearly indicated that the SiO2-rich phase in inclusions from augite in meteorites from Northwest Africa site is re-crystallized, whereas it is still vitreous in the inclusions from Nakhla sampling site. Therefore, different post-entrapment evolutions were active for the two nakhlite meteorite sets, the Nakhla and the NWA817 set. Melt inclusions in Nakhla olivine presented alteration veins, which were presumably produced before their landing on Earth. If this is the case, this would indicate a alteration stage already on Mars with all the consequence in terms of climate history. Melt inclusions in Nakhla augite resulted unaffected by any alteration or modification following the entrapment, and therefore represent the best candidate to indicate the pristine magma composition. 相似文献
246.
各向异性材料界面周期刚性线夹杂的反平面问题 总被引:3,自引:1,他引:2
研究了两种各向异性材料界面含周期分布刚性线夹杂的反平面剪切问题。运用复变函数方法,获得了封闭形式解答,并给出了刚性线尖端应力场公式,从该文解答的特殊情形,可直接导出各向同性材料界面以及均匀各向异性材料中相应问题的公式,其极限情形与已有的结果吻合。 相似文献
247.
研究了一类含极大η-单调算子的广义非线性混合似变分包含组.依据不动点理论和极大η-单调算子的预解算子技巧,在Hilbert空间中提出了一种求这类变分不等式组的逼近解的扰动迭代算法,并证明了这类算法的收敛性和稳定性.所得结果是新的,并推广和统一了近期文献中的一些相关结论. 相似文献
248.
A-Monotonicity and Its Role in Nonlinear Variational Inclusions 总被引:1,自引:0,他引:1
R. U. Verma 《Journal of Optimization Theory and Applications》2006,129(3):457-467
The notion of A-monotonicity in the context of solving a new class of nonlinear variational inclusion problems is presented. Since A-monotonicity generalizes not only the well-explored maximal monotone mapping, but also a recently introduced and studied notion of H-monotone mapping, the results thus obtained are general in nature.Communicated by G. Leitmann 相似文献
249.
In this paper, we establish the existence of solutions to systems of second order differential inclusions with maximal monotone terms. Our proofs rely on the theory of maximal monotone operators and the Schauder degree theory. A notion of solution-tube to these problems is introduced. This notion generalizes the notion of upper and lower solutions of second order differential equations. 相似文献
250.
A. V. Zuev 《Mathematical Notes》2006,79(3-4):518-527
A new version of the method of translation along trajectories, which does not require the uniqueness of the solution of the Cauchy problem, is applied to the proof of the existence theorem for vector-valued periodic solutions of ordinary differential equations of first and second order. This result is applicable to equations and differential inclusions with discontinuous right-hand side. Several applications of the theorems proved in this paper are considered in cases which are not covered by the classical theory of ordinary differential equations with continuous right-hand side and equations with right-hand side satisfying the Carathéodory conditions. 相似文献