摘要:

AbstractWe study the initial‐boundary value problem for ∂t2u(t,x)+A(t)u(t,x)+B(t)∂tu(t,x)=f(t,x) on [0,T]×Ω(Ω⊂ℝn) with a homogeneous Dirichlet boundary condition; hereA(t) denotes a family of uniformly strongly elliptic operators of order 2m,B(t) denotes a family of spatial differential operators of order less than or equal tom, anduis a scalar function. We prove the existence of a unique strong solutionu. Furthermore, an energy estimate

ISSN:0170-4214    

DOI:10.1002/mma.1670150702

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractWe prove the existence of weak global solutions to the degenerate diffusion equation (1) with singular absorption term. Moreover we investigate the regularity up to the quenching time and we show by means of explicit solutions that our regularity results are optimal.

ISSN:0170-4214    

DOI:10.1002/mma.1670150703

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractThe existence of a weak solution of a two‐dimensional non‐stationary free‐boundary problem related to flame propagation is established. The main feature of the problem is that the nonlinear coupling of the two parabolic equations occur on the free boundary and has exponential g

ISSN:0170-4214    

DOI:10.1002/mma.1670150704

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractWe examine the existence and regularity results for a scalar conservation law with a convexity condition and solve its weak solution with shocks by using a special method of characterization combined with a representation formula for the weak solution.

ISSN:0170-4214    

DOI:10.1002/mma.1670150705

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractWe present a mathematical model of a communication system perturbed by statistical sampling errors (timing jitter). The aim is to find an ‘optimal’ impulse response for the system, the optimization problem actually being a minimax problem. that is we put the model into a game‐theoretical framework. The basic game turns out to be a statistical game similar to those arising from estimation problems in statistics.Earlier results concerning least‐favourable sampling error distributions published by Krabs and Vogel are supplemented by estimations of the number of support points of the least‐favourable distribution.Furthermore, we state the existence of the saddle points of our game, which formerly has only been proved for some special cases. In the first part we treat the general situation, where one strategy set for the game—the set of all feasible impulse responses—forms a vector space with infinite dimension. In the second part we discuss the problem in the case that the impulse responses are restricted to a finite‐dimensional subspace of the whole infinite‐dim

ISSN:0170-4214    

DOI:10.1002/mma.1670150706

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

ISSN:0170-4214    

DOI:10.1002/mma.1670150701

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY