Can Datalog Be Approximated?

All possible chaotic dynamics can be approximated in three dimensions

It is known that neither onenor two-dimensional ordinary differential equations can exhibit chaotic phenomena, while such behaviour is possible in threedimensional systems. Here it is shown that the solutions of any dissipative equation can be approximated arbitrarily closely by the trajectories of an appropriate threedimensional system. This class includes the Navier-Stokes equations, showing ...

What Can Be Approximated by Polynomials with Integer Coefficients

Can billiard eigenstates be approximated by superpositions of plane waves ?

The plane wave decomposition method (PWDM) is one of the most popular strategies for numerical solution of the quantum billiard problem. The method is based on the assumption that each eigenstate in a billiard can be approximated by a superposition of plane waves at a given energy. By the classical results on the theory of differential operators this can indeed be justified for billiards in con...

Optimizing Inequality Joins in Datalog with Approximated Constraint Propagation

Datalog systems evaluate joins over arithmetic (in)equalities as a naive generate-and-test of Cartesian products. We exploit aggregates in a source-to-source transformation to reduce the size of Cartesian products and to improve performance. Our approach approximates the well-known propagation technique from Constraint Programming. Experimental evaluation shows good run time speed-ups on a rang...

How can Alzheimer's Patients be Helped?

پرستاری از بیمار مبتلا به بیماری آلزایمر چندان ساده نیست. حتی اگر از این امر که اختلال رفتاری فرد نشانه ای از بیماری اوست، آگاه باشید، اکثر مواقع نمی دانید که چگونه باید با او رفتار کنید. در این مقاله روشهای مناسبی ارائه گردیده تا خانواده بیمار بتواند با ۱۰ اختلال رفتاری شایع در بیماران مبتلا بدون احساس ناامیدی و خشم سازگاری یابند.