The hadronic decay rate of the τ lepton serves as one of the most precise determinations of the QCD coupling αs. The dominant theoretical source of uncertainty at present resides in the seeming disparity of two approaches to improving the perturbative expansion with the help of the renormalisation group, namely fixed-order and contourimproved perturbation theory. In this work it is demonstrated...

It has long been known that perturbative calculations are necessary for precision measurements of many quantities. Unfortunately perturbation theory using a lattice cutoff is difficult, due to extra diagrams and vastly more complicated Feynman rules. The complexity of these calculations is an impediment to doing the higher–order perturbation theory required for many important applications of im...

We present results at one-loop order of perturbation theory for various improvement coefficients in on-shell O(a) improved lattice QCD. In particular we determine the additive counterterm required for on-shell improvement of the isovector vector current. Employing a general mass-independent renormalization scheme we also obtain the coefficients of the O(a) counterterms which are proportional to...

In applied game theory the motivation of players is a key element. It is encoded in the payoffs of the game form and often based on utility functions. But there are cases were formal descriptions in the form of a utility function do not exist. In this paper we introduce a representation of games where players’ goals are modeled based on so-called higher-order functions. Our representation provi...

This paper summarizes the current state of the art in the topics of rst-order theory revision and theory restructuring. The various tasks involved in rst-order theory reenement (revision vs. restructuring) are deened and then discussed in turn. For theory revision, the issue of minimality is discussed in detail, and a general outline algorithm is given which identiies the major places of diiere...

Nowadays, the most generated electrical energy is consumed by three-phase induction motors. Thus, in order to carry out preventive measurements and maintenances and eventually employing high-efficiency motors, the efficiency evaluation of induction motors is vital. In this paper, a novel and efficient method based on Improved Big Bang-Big Crunch (I-BB-BC) Algorithm is presented for efficiency e...

Classical decision theory models behaviour in terms of utility maximisation where utilities represent rational preference relations over outcomes. However, empirical evidence and theoretical considerations suggest that we need to go beyond this framework. We propose to represent goals by higherorder functions or operators that take other functions as arguments where the max and argmax operators...