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991.
Josef Malík 《Applications of Mathematics》1998,43(6):413-438
The main goal of the paper is to give a variational formulation of the behaviour of bolt systems in rock mass. The problem arises in geomechanics where bolt systems are applied to reinforce underground openings by inserting steel bars or cables. After giving a variational formulation, we prove the existence and uniqueness and some other properties. 相似文献
992.
Hiroshi Shibata 《Physica A》1998,260(3-4)
Disorderness of spatiotemporal patterns which are obtained by nonlinear partial differential equations is characterized quantitatively. The mean Lyapunov exponent for a nonlinear partial differential equation is given. The local Lyapunov exponent which is a finite time average of the mean Lyapunov exponent is shown to have close relation to the spatiotemporal patterns. It is suggested that the systems which are described by nonlinear partial differential equations are characterized statistically through the probability distribution function of the local Lyapunov exponent. 相似文献
993.
Martin Schechter 《Mathematische Nachrichten》1997,183(1):201-210
We study semilinear problems in which the nonlinear part is linear at infinity but behaves like a function intersecting many of the eigenvalues of the linear operator. The asymptotic linear operator can have a null space of any finite dimension. 相似文献
994.
A. I. Ivanov R. G. Zhbankov E. A. Korolenko E. V. Korolik L. A. Meleshchenko V. V. Sarnatskaya V. G. Nikolaev V. V. Nikolaichik L. A. Yushko 《Journal of Applied Spectroscopy》1997,64(1):29-35
Differential scanning calorimetry and IR spectrosocopy were used to investigate the effect of the procedure of isolation of
human serum albumin on its physicochemical characteristics. It is shown that fractionation of blood plasma with ethylene glycol
followed by ion exchange chromatography can be used to obtain albumin of normal donors that is similar to the albumin in the
nonfractionated plasma according to melting thermograms. Endotherms of human serum albumin samples that were obtained by affinity
chromatography and preparative electrophoresis are bimodal, unlike the monophasic for albumin obtained by polyethylene glycol
precipitation. These changes result from a higher content of nonetherified fatty acids in the albumin samples obtained by
affinity chromatography and from modification of the secondary protein structure in the samples obtained by electrophoresis.
Analysis of melting thermograms of serum albumin from patients with uremia, chronic hepatitis, and peritonitis shows that
fractionation of blood with polyethylene glycol preserves the thermodynamic characteristics of the various pathological serum
albumins to the greatest extent. The present results demonstrate the advantage of polyethylene glycol fractionation for isolation
of native preparations of normal and “pathological” human serum albumin.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 32–37, January–February, 1997. 相似文献
995.
Jelena Randjelovi? 《Journal of Mathematical Analysis and Applications》2007,326(1):266-280
The paper discusses the pth moment exponential stability for a general class of neutral stochastic functional differential equations of the Ito type. This investigation can be very complicated, even in many special cases, by using usual methods based on Lyapunov functionals. In this paper we present criteria which are relatively easy to verify the pth moment exponential stability of the solutions of such equations. 相似文献
996.
§ 1 . Introduction AclassofintegraldifferentialequationsDirichletboundaryvalueproblemsforordinarydif ferentialequationandellipticequationarediscussedin [1]and [2 ]respectively .Andin [3]akindofnonlocalproblemsforsingularlyperturbedreactiondiffusionsystemsarestudied.Inthispaper,whatisworthpointingoutisaclassofnonlinearboundaryvalueproblemsdiscussed,applyingthemethodofcompositeexpandandthetheoryofdifferentialinequalities.εy″ =f(x ,y ,Tεy ,ε) y′ +g(x ,y ,Tεy,ε) ,0 相似文献
997.
998.
61.IntroductionConsiderthesecondordersuperlinearequationx'(t) p(t)X'(t) q(t)1x(t)l"sgnx(t)=o,t>to,(1)wherea>l,pandq:[t,'co)-R=(-co,oo)arecontinuous.Weconsideronlysuchsolutionsxofequation(l)whichexistonsomeinterval[t.,oo),t.>t,>o.Asolutionofequation(l)issaidtobeoscillatoryifithasarbitrarilylargezerosandotherwise,itissaidtobenonoscillatory.Equation(l)iscalledoscillatoryifallofitssolutionsareoscilllatory.Forthespecialcasewherep(t)=Oli.e.,forthedifferentialequationx'(t) q(t)lx(t)l"sgnx(t)=o,a>1-… 相似文献
999.
中立型抛物方程解的强迫振动性 总被引:2,自引:0,他引:2
本文讨论中立型抛物方程解的强迫振动,其中Ω是Rn中具有光滑边界Ω的有界区域, 相似文献
1000.
博弈论为理论依据,通过对高、低两种任务下买税利益团体和上级监管部门的利益偏好和行为特征进行建模对比分析,考察影响其行为的各种因素,从经济学角度探求引起“买税”行为的根源,并试着给出建议. 相似文献