We illustrate some recent results on exact solutions to discrete-time l1-norm minimization problems with convolution constraints. A fixed-point property for this class of problems is introduced. The convolution constraints can be interpreted as a dynamic system with initial conditions. We show by construction that optimal solutions with a rational Z-transform exist for any initial conditions sa...

The complexity of modern communication systems, particularly in the wireless domain, grows at an astounding rate, which causes increasing time-to-market. In order to provide a shorter timeto-market, mostly manually performed design tasks are to be overcome and an automation of the design process is needed. This paper presents approaches for automated design steps starting with high level algori...

Effective memory utilization is critical to reap the benefits of the multi-core processors emerging on embedded systems. In this paper we explore the use of a stream model to effectively utilize memory hierarchies. We target image processing algorithms running on the Analog Devices Blackfin BF561 fixedpoint, dual-core DSP. Using optimized assembly to effectively use cores reduces runtime, but a...

This paper gives three noncompact variants of Lefschetz–Nielsen fixed-point theory parallel to developments that have occurred in surgery theory. Thus, we study when a proper map can be properly homotoped, or boundedly homotoped, or even homotoped in a C bounded fashion to a fixedpoint free map. As an example, the universal cover of a compact aspherical manifold always has a fixed-point free se...

The Split-Field Finite-Difference Time-Domain (SFFDTD) formulation is extended to periodic structures with Kerr-type nonlinearity. The optical Kerr effect is introduced by an iterative fixedpoint procedure for solving the nonlinear system of equations. Using the method, formation of solitons inside homogenous nonlinear media is numerically observed. Furthermore, the performance of the approach ...

We present two examples of nice normal spaces X having the property that for some fixedpoint free homeomorphism on X its tech-Stone extension has a fixed point. One of the spaces presented here is locally countable, locally compact, separable, normal, countably paracompact and weakly zero-dimensional. The other one is hereditarily normal and strongly zero-dimensional. Our construction of this e...

In this paper, we first establish a new fixed point theorem for a Meir-Keeler type condition. As an application, we derive a simultaneous generalization of Banach contraction principle, Kannan's fixed point theorem, Chatterjea's fixed point theorem and other fixed point theorems. Some new fixed point theorems are also obtained.

where h ∈ L1(0,T ;X) and f : [0,T ]×X →X. This is obtained if one takes F(u)(t)= h(t)−∫ t 0 a(t−s)f (s,u(s))ds in (1.1). Such problems are important from the viewpoint of applications since they cover nonlocal generalizations of integrodifferential equations arising in the mathematical modeling of heat conduction in materials with memory. Byszewski [6, 7] initiated the work concerning abstract ...

We present a compositional method which allows to overapproximate the set of attractors and under-approximate the set of basins of attraction of a Boolean network (BN). This merely consists in replacing a global fixed-point computation by a composition of local fixedpoint computations. Once these approximations have been computed, it becomes much more tractable to generate the exact sets of att...

Fixed-point simulation results are used for the performance measure of inverting matrices by Cholesky decomposition. The fixed-point Cholesky decomposition algorithm is implemented using a fixed-point reconfigurable processing element. The reconfigurable processing element provides all mathematical operations required by Cholesky decomposition. The fixed-point word length analysis is based on s...