Negative capacitance and its photo-inhibition in organic bulk heterojunction devices

We report the dynamic admittance, both in the dark and under illumination, of heterojunctions made of poly(3-hexyl thiophene)/1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C₆₁ (P3HT:PCBM) blends, which are used in efficient organic solar cells. In the dark there appears a huge low frequency negative capacitance which we associate with slow electron hole bimolecular recombination at the heterojunction interfaces. Surprisingly, under photoexcitation the negative capacitance gradually disappears with increasing light intensity. We attribute this positive photoinduced capacitance to the combined effect of (1) long lived photogenerated charges at the P3HT:PCBM interfaces that increase electron-hole bimolecular recombination rate, which in turn renders the capacitance less negative and (2) trapped photogenerated charges that increase the capacitance upon re-emission.     

Bio-inspired delayed evolutionary game dynamics with?networking applications

We study in this paper some evolutionary games where competition between individuals from a large population occurs through many local interactions between randomly selected individuals. We focus on games that have the property of possessing a single interior evolutionarily stable strategy (ESS). We study in particular the effect of the time delays on the convergence of evolutionary dynamics to the ESS in an evolutionary game in which each pure strategy is associated with its own delay. In particular, we study a multiple access game as well as a Hawk and Dove game. We study the properties of the ESS in these games and also the effect of time delays on the convergence of various bio-inspired evolutionary game dynamics to the ESS.     

Congestion control as a stochastic control problem with action delays

We consider the design of explicit rate-based congestion control for high-speed communication networks and show that this can be formulated as a stochastic control problem where the controls of different users enter the system dynamics with different delays. We discuss the existence, derivation and the structure of the optimal controller, as well as of suboptimal controllers of the certainty-equivalent type — a terminology that is precisely defined in the paper for the specific context of the congestion control problem considered. We consider, in particular, two certainty-equivalent controllers which are easy to implement, and show that they are stabilizing, i.e., they lead to bounded infinite-horizon average cost, and stable queue dynamics. Further, these controllers perform well in simulations.     

Feature‐Preserving Surface Completion Using Four Points

We present a user‐guided, semi‐automatic approach to completing large holes in a mesh. The reconstruction of the missing features in such holes is usually ambiguous. Thus, unsupervised methods may produce unsatisfactory results. To overcome this problem, we let the user indicate constraints by providing merely four points per important feature curve on the mesh. Our algorithm regards this input as an indication of an important broken feature curve. Our completion is formulated as a global energy minimization problem, with user‐defined spatial‐coherence constraints, allows for completion that adheres to the existing features. We demonstrate the method on example problems that are not handled satisfactorily by fully automatic methods.     

Equilibrium, Games, and Pricing in Transportation and Telecommunication Networks

Network equilibrium models that have traditionally been used for transportation planning have penetrated in recent years to other scientific fields. These models have recently been introduced in the telecommunication networks literature, as well as in the field of game theory. Researchers in the latter fields are not always aware of the very rich literature on equilibrium models outside of their application area. On the other hand, researchers that have used network equilibrium models in transportation may not be aware of new application areas of their tools. The aim of this paper is to present some central research issues and tools in network equilibria and pricing that could bring closer the three mentioned research communities.     

On the physical mechanism of the NROM memory erase

The purpose of this paper is to investigate the physical mechanism of NROM memory erase. Three conduction mechanisms potentially responsible of NROM erase will be analyzed (tunneling and emission of electrons through both bottom and top oxide, tunneling and injection of holes over the bottom oxide barrier) by means of standard two-dimensional simulations and ad-hoc models reproducing hole and electron transport mechanisms across the oxide not included in standard device simulators. Hot-hole injection will be identified as the actual conduction mechanism of NROM erase, and two compact models capable to describe the main characteristics of NROM erase current will be developed.     

The validity of psychophysiological detection of information with the Guilty Knowledge Test: A meta-analytic review.

The authors performed a meta-analysis based on 169 conditions, gathered from 80 laboratory studies, to estimate the validity of the Guilty Knowledge Test (GKT) with the electrodermal measure. The over-all average effect size was 1.55, but there were considerable variations among studies. In particular, mock-crime studies produced the highest average effect size (2.09). Three additional moderators, were identified: Motivational instructions, deceptive ("no") verbal responses, and the use of at least 5 questions were associated with enhanced validity. Finally, a set of 10 studies that best approximated applications of the GKT under optimal conditions produced an average effect size of 3.12. The authors discuss factors that might limit the generalizability of these results and recommend further research of the GKT in realistic setups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)