Let G be a finite graph with p vertices and x its chromatic polynomial. A combinatorial interpretation is given to the positive integer (-l)px(-A), where h is a positive integer, in terms of acyclic orientations of G. In particular, (-l)Px(-1) is the number of acyclic orientations of G. An application is given to the enumeration of labeled acyclic digraphs. An algebra of full binomial type, in ...

A unique sink orientation (USO) is an orientation of the n-dimensional cube graph (n-cube) such that every face (subcube) has a unique sink. The number of unique sink orientations is nΘ(2 n) [13]. If a cube orientation is not a USO, it contains a pseudo unique sink orientation (PUSO): an orientation of some subcube such that every proper face of it has a unique sink, but the subcube itself hasn...

Article history: Received 10 July 2006 Available online 29 August 2008

The 31 ICFA Advanced Beam Dynamics Workshop on Electron-Cloud Effects “ECLOUD’04” was held April 19-23, 2004 at Napa, CA, USA. A broad range of current topics in this field were illuminated by 53 talks in 7 sessions plus 6 session summaries at the final summary session. These covered a variety of experimental methods and results, along with progress on understanding of the topic obtained from s...

In this paper, the feasibility of current internet framework for future usage is investigated. Internet has been a huge success. However, the scale of its use has given rise to issues and challenges which were not taken into account when it was created. There is a strong perception in the research community that current internet framework is not adequate to meet the current needs and challenges...

Bruno S. Frey suggests nine Proposals to refine future democratic processes. This paper unifies subsets of Frey’s Proposals. In doing so, certain Proposals are further supported while others are challenged. In addition, I suggest that our increased global reliance as well as advances in technology should force further changes to our democratic institutions.

‘Future Designers’ is an interactive and participative crash course that aims to introduce to children the concepts and practice of ‘creativity’, ‘design’, and ‘design thinking’. The course targets multiple learning styles and intelligences, combining various learning approaches and tools. The full course lasts 4-5 hours and can be delivered in a single or two sessions. Up to now, five pilot st...