All sets of lines providing a partition of the set of internal points to a conic C in PG(2, q), q odd, are determined. There exist only three such linesets up to projectivities, namely the set of all nontangent lines to C through an external point to C, the set of all nontangent lines to C through a point in C, and, for square q, the set of all nontangent lines to C belonging to a Baer subplane...

In this work we deploy a mechanism design approach for allocating a divisible commodity (electricity in our example) among consumers. We consider each consumer with an associated personal valuation function of the energy resource during a certain time interval. We aim to select the optimal consumption profile for every user avoiding consumption peaks when the total required energy could exceed ...

We are interested in the question of how much the order of a non-standard model of PA can determine the model. In particular, for a model M , we want to characterize the complete types p(x, y) of non-standard elements (a, b) such that the linear orders {x : x < a} and {x : x < b} are necessarily isomorphic. It is proved that this set includes the complete types p(x, y) such that if the pair (a,...

Efficient evaluation of similarity queries is one of the basic requirements for advanced multimedia applications. In this paper, we consider the relevant case where complex similarity queries are defined through a generic language L and whose predicates refer to a single feature F . Contrary to the language level which deals only with similarity scores, the proposed evaluation process is based ...

CONTENTS 1. Introduction 2. Aim of the review 3. What are adventure games? 4. History and classification of adventure games 5. Adventure games today 6. Games as a form of literacy 7. Embedding elements of storytelling within games 8. Games for learning 9. Summary and main conclusions 10. Points to consider when designing game authoring tools for the development of storytelling 11. Glossary of k...

The notion of a strongly determined type over A extending p is introduced , where p 2 S(A). A strongly determined extension of p over A assigns, for any model M A, a type q 2 S(M) extending p such that, if c realises q, then any elementary partial map M ! M which xes acl eq (A) pointwise is elementary over c. Examples are provided of many theories with strongly determined types, and some withou...

A re we alone in the universe? How can we find out? What would happen if we made contact with extraterrestrial life forms, intelligent or otherwise? These questions have fascinated humans ever since we understood that there is a universe beyond our pale blue dot. As the British physicist and author Arthur C Clarke put it: “Two possibilities exist: either we are alone in the universe or we are n...

We introduce a sealed bid auction of a single item in which the winner is chosen at random among the highest k bidders according to a fixed probability distribution, and the price for the chosen winner is the Vickrey-Clarke-Groves price. We call such an auction a cascade auction. Our analysis suggests that this type of auction may give higher revenues compared to second price auction in cases o...

This paper uses the Clarke mechanism to construct an incentive compatible tâtonnement process which converges to the Lindahl allocation of a public good economy. We show truth telling is an equilibrium in the infinite horizon game induced by the tâtonnement. JEL Codes: C72, D44, H41