The spectrum of known black hole solutions to the stationary Einstein equations has increased in an unexpected way during the last decade. In particular, it has turned out that not all black hole equilibrium configurations are characterized by their mass, angular momentum and global charges. Moreover, the high degree of symmetry displayed by vacuum and electro-vacuum black hole space-times ceas...

The quintessential crime of the information age is identity theft, the malicious use of personal identifying data. In this paper we model “identity” and its use in credit transactions. Various types of identity theft occur in equilibrium, including “new account fraud,” “existing account fraud,” and “friendly fraud.” The equilibrium incidence of identity theft represents a tradeoff between a des...

In evolutionary games the fitness of individuals is not constant but depends on the relative abundance of the various strategies in the population. Here we study general games among n strategies in populations of large but finite size. We explore stochastic evolutionary dynamics under weak selection, but for any mutation rate. We analyze the frequency dependent Moran process in well-mixed popul...

This paper describes LaoGEM (Lao General Equilibrium Model), a 20 sector, 400 household general equilibrium model of the Lao economy, constructed specifically for the analysis of the effect of road improvement on rural poverty incidence in Laos. Unless otherwise stated, the database of the model refers to the year 2002. These features are relatively standard for comparative static general equil...

In this paper, we search optimal grasp points and configurations of fingers for not only resisting an external force applied to a grasped object but also generating a desirable acceleration of the object. Based on the concept of required external force set, we define required acceleration and equilibrium-force sets. By using the sets, we formulate an optimization problem from the viewpoint of d...

The ability to recognize a shape is linked to figure-ground (FG) organization. Cell preferences appear to be correlated across contrast-polarity reversals and mirror reversals of polygon displays, but not so much across FG reversals. Here we present a network structure which explains both shape-coding by simulated IT cells and suppression of responses to FG reversed stimuli. In our model FG seg...

nowadays, many governments have found that the main cause of water crises in agricultural sector related to neglecting farmers’ role in irrigation and drainage networks management. water users association has been considered in order to transferring irrigation management to local beneficiaries. if farmers' opinion toward such transferring don't be investigated, it may lead to failure....