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DIFFERENTIAL HARNACK ESTIMATES FOR TIME-DEPENDENT HEAT EQUATIONS WITH POTENTIALS
EQUATIONS WITH POTENTIALS DIFFERENTIAL HARNACK
2015/8/17
In this paper, we prove a differential Harnack inequality for positive
solutions of time-dependent heat equations with potentials. We also prove a gradient
estimate for the positive solution o...
A RATIO TEST IN ACTIVE CONTROL NON-INFERIORITY TRIALS WITH A TIME-TO-EVENT ENDPOINT
Active control Fixed margin Fraction retention
2015/3/18
There are essentially two kinds of non-inferiority hypotheses in an active control trial:
fixed margin and ratio hypotheses. In a fixed margin hypothesis, the margin is a
prespecified constant and t...
Reduction of Markov chains with two-time-scale state transitions
Reduction Markov chain time scale approximation limit behavior
2014/12/5
We consider a general class of two-time-scale Markov chains whose transition rate matrices
depend on a parameterI. We assume that some transition rates of the Markov chain will tend to
infinity as I...
On the Muskat problem: global in time results in 2D and 3D
Porous media incompressible ows uid interface global existence.
2014/4/3
This paper considers the three dimensional Muskat problem in the stable regime.We obtain a conservation law which provides an L2 maximum principle for the uid interface. We also show global in time ex...
Long time existence of the symplectic mean curvature flow
symplectic mean curvature flow Long time Differential Geometry
2011/8/25
Abstract: Let $(M,\bar{g})$ be a K\"ahler surface with a constant holomorphic sectional curvature $k>0$, and $\Sigma$ an immersed symplectic surface in $M$. Suppose $\Sigma$ evolves along the mean cur...
This paper develops a structural credit risk model to characterize the difference between the economic and recorded default times for a firm.
Riemannian $\mathbf{(1+d)}$-Dim Space-Time Manifolds with Nonstandard Topology which Admit Dimensional Reduction to Any Lower Dimension and Transformation of the Klein-Gordon Equation to the $\mathbf{1}$-Dim Schrödinger Like Equation
Riemannian $\mathbf{(1+d)}$-Dim Space-Time Manifolds Nonstandard Topology Any Lower Dimension Transformation of the Klein-Gordon Equation $\mathbf{1}$-Dim Schrö dinger Like Equation
2011/2/21
This rather technical paper presents some generalization of the results of recent publications [1–3]where toy models of dimensional reduction of space-time were considered.
Balanced realizations of discrete-time stable all-pass systems and the tangential Schur algorithm
Balanced realizations of discrete-time stable all-pass systems tangential Schur algorithm
2011/2/21
In this paper, the connections are investigated between two different approaches towards
the parametrization of multivariable stable all-pass systems in discrete-time. The first approach involves the...
Tracing light propagation to the intrinsic accuracy of space-time geometry
relativity gravitation space-time geometry weak field approximations light propagation
2011/3/4
Advancement in astronomical observations and technical instrumentation requires coding light
propagation at high level of precision; this could open a new detection window of many subtle relativistic...
Linearized inverse scattering based on seismic Reverse Time Migration
Linearized inverse seismic Reverse Time Migration
2011/2/23
In this paper we study the linearized inverse problem associated with imaging of re ection seismic data.
Analytical Determination of Fractal Structure in Stochastic Time Series
Fractal Structure Stochastic Time Series
2010/4/8
Current methods for determining whether a time series exhibits fractal structure (FS) rely on subjective assessments on estimators of the Hurst exponent (H). Here, I introduce the Bayesian Assessment ...
On Pseudohyperbolical Curves in Minkowski Space-Time
Minkowski space--time pseudohyperbolic space curvature
2010/3/1
In this paper, we characterize all spacelike, timelike and null curves lying on the pseudohyperbolic space H03 in the Minkowski space--time E14. Moreover, we prove that there are no timelike and no nu...
Time-Periodic Solutions of the Einstein's Field Equations II: Geometric Singularities
Einstein's ˉeld equations time-periodic solution Riemann curvature tensor singu- larity event horizon
2018/4/20
In this paper, we construct several kinds of new time-periodic solutions of the vacuum Einstein's field equations whose Riemann curvature tensors vanish, keep finite or take the infinity at some point...