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901.
§ 1 IntroductionRecently,certain three-point boundary value problems for nonlinear ordinarydifferential equations have been studied by many authors[1— 6] .However,few papers havebeen published on the same problems for nonlinear functional differential equations.In thispaper,we are concerned with the following second order differential equation with anadvanced argumentu″(t) +λa(t) f(u(h(t) ) ) =0 ,t∈ (0 ,1 ) (1 .1 )with the three-point boundary conditionsu(0 ) =0 ,αu(η) =u(1 ) ,(1 .2 )… 相似文献
902.
王明新 《中国科学A辑(英文版)》2003,46(2):169-175
This paper deals with the blow-up rate estimates of positive solutions for systems of heat equations with nonlinear boundary conditions. The upper and lower bounds of blow-up rate are obtained. 相似文献
903.
SOME NEW RESULTS FOR NONLINEAR BOUNDARY VALUE PROBLEMS OF MIXED TYPE INTEGRODIFFERENTIAL EQUATION 总被引:1,自引:0,他引:1
In this paper we give the existence and uniqueness of solutions for boundary value problems of the form u" = f(t, u,u', T1u,T2u), g(u(0),u(1)) = 0, h(w(0), u(1),u'(0), u'(1)) = 0 by means of the upper and lower solution method. 相似文献
904.
Sigal Leviatan 《International Journal of Game Theory》2003,31(3):383-410
The consistent value is an extension of the Shapley value to the class of games with non-transferable utility.? In this paper,
the consistent value will be characterized for market games with a continuum of players of two types. We will show that for
such games the consistent value need not belong to the core, and provide conditions under which there is equivalence between
the two concepts.
Received: October 1998
RID="*"
ID="*" This thesis was completed under the supervision of Professor Sergiu Hart, The Center for Rationality and Interactive
Decision Theory, Department of Mathematics, Department of Economics, The Hebrew University of Jerusalem. I would like to thank
Professor Hart for introducing me to this area of research, for his help and guidance, and, especially, for all his patience.? I
would also like to thank Michael Borns for improving the style, and an anonymous referee for helpful comments. 相似文献
905.
It is proved that Youngs [4] axiomatization for the Shapley value by marginalism, efficiency, and symmetry is still valid for the Shapley value defined on the class of nonnegative constant-sum games with nonzero worth of grand coalition and on the entire class of constant-sum games as well.The research was supported by NWO (The Netherlands Organization for Scientific Research) grant NL-RF 047-008-010.I am thankful to Theo Driessen, Natalia Naumova and Elena Yanovskaya for interesting discussions and comments. The useful remarks of two anonymous referees are also appreciated. 相似文献
906.
In this paper, we introduce a new class of vector quasi-equilibrium problems with set-valued maps. Almost all the vector equilibrium models of the Blum-Oettli type in the literature are special cases of our new class of equilibrium problems under consideration. Moreover, a number of C-diagonal quasiconvexity properties are proposed for set-valued maps, which are natural generalizations of the -diagonal quasiconvexity for real functions. Together with an application of continuous selection and fixed-point theorems, these conditions enable us to prove unified existence results of solutions for such vector equilibrium problems. 相似文献
907.
A Global Solution to a
Two-dimensional Riemann Problem Involving Shocks as Free
Boundaries 总被引:4,自引:0,他引:4
YuxiZheng 《应用数学学报(英文版)》2003,19(4):559-572
We present a global solution to a Riemann problem for the pressure gradient system of equations.The Riemann problem has initially two shock waves and two contact discontinuities. The angle between the two shock waves is set initially to be close to 180 degrees. The solution has a shock wave that is usually regarded as a free boundary in the self-similar variable plane. Our main contribution in methodology is handling the tangential oblique derivative boundary values. 相似文献
908.
Let
be a compact set with interior G. Let L
1
(G,dx), >0 dx-a.e. on G, and m:=dx. Let A=(a
ij
) be symmetric, and globally uniformly strictly elliptic on G. Let be such that
; f,
, is closable in L
2
(G,m) with closure (
r
,D(
r
)). The latter is fulfilled if satisfies the Hamza type condition, or
i
L
1
loc
(G,dx), 1id. Conservative, non-symmetric diffusion processes X
t
related to the extension of a generalized Dirichlet form
where
satisfies
are constructed and analyzed. If G is a bounded Lipschitz domain, H
1,1
(G), and a
ij
D(
r
), a Skorokhod decomposition for X
t
is given. This happens through a local time that is uniquely associated to the smooth measure 1{
Tr
()>0}
d, where Tr denotes the trace and the surface measure on G.This research has been financially supported by TMR grant HPMF-CT-2000-00942 of the European Union.
Mathematics Subject Classification (2000): 60J60, 60J55, 31C15, 31C25, 35J25 相似文献
909.
This paper examines the complexity of global verification for MAX-SAT, MAX-k-SAT (for k3), Vertex Cover, and Traveling Salesman Problem. These results are obtained by adaptations of the transformations that prove such problems to be NP-complete. The class of problems PGS is defined to be those discrete optimization problems for which there exists a polynomial time algorithm such that given any solution , either a solution can be found with a better objective function value or it can be concluded that no such solution exists and is a global optimum. This paper demonstrates that if any one of MAX-SAT, MAX-k-SAT (for k3), Vertex Cover, or Traveling Salesman Problem are in PGS, then P=NP. 相似文献
910.
We present a detailed proof of the existence-theorem for noncommutative spectral sections (see the noncommutative spectral flow, unpublished preprint, 1997). We apply this result to various index-theoretic situations, extending to the noncommutative context results of Booss–Wojciechowski, Melrose–Piazza and Dai–Zhang. In particular, we prove a variational formula, in K*(Cr*(Γ)), for the index classes associated to 1-parameter family of Dirac operators on a Γ-covering with boundary; this formula involves a noncommutative spectral flow for the boundary family. Next, we establish an additivity result, in K*(Cr*(Γ)), for the index class defined by a Dirac-type operator associated to a closed manifold M and a map r:M→BΓ when we assume that M is the union along a hypersurface F of two manifolds with boundary M=M+ F M−. Finally, we prove a defect formula for the signature-index classes of two cut-and-paste equivalent pairs (M1,r1:M1→BΓ) and (M2,r2:M2→BΓ), whereand φjDiff(F). The formula involves the noncommutative spectral flow of a suitable 1-parameter family of twisted signature operators on F. We give applications to the problem of cut-and-paste invariance of Novikov's higher signatures on closed oriented manifolds. 相似文献
M1=M+ (F,φ1) M−, M2=M+ (F,φ2) M−