Discriminatory processor sharing queues with stationary ergodic service times and the performance of TCP in overload

In a recent paper, Bonald and Roberts (2001) [6] studied non-persistent TCP connections in transient overload conditions, under the assumption that all connections have the same round-trip times. In this paper our goal is to develop theoretical tools that will enable us to relax this assumption and obtain explicit expressions for the rate of growth of the number of connections at the system, the rate at which TCP connections leave the system, as well as the time needed for the completion of a connection. To that end, we model the system as a discriminatory processor sharing (DPS) system which we analyze under very mild assumptions on the probability distributions related to different classes of arrivals: we only assume that the arrival rates of connections exist, and that the amount of information transmitted during a connection of a given type forms a stationary ergodic sequence. We then proceed to obtain explicit expressions for the growth rate of the number of connections at the DPS system for several specific probability distributions. We check through simulations the applicability of our queueing results for modeling TCP connections sharing a bottleneck.     

NROM: A novel localized trapping, 2-bit nonvolatile memory cell

This paper presents a novel flash memory cell based on localized charge trapping in a dielectric layer and on a new read operation. It is based on the storage of a nominal ~400 electrons above a n⁺/p junction. Programming is performed by channel hot electron injection and erase by tunneling enhanced hot hole injection. The new read methodology is very sensitive to the location of trapped charge above the source. This single device cell has a two physical bit storage capability. The cell shows improved erase performances, no over erase and erratic bit issues, very good retention at 250°C, and endurance up to 1M cycles. Only four masks are added to a standard CMOS process to implement a virtual ground array. In a typical 0.35 μm process, the area of a bit is 0.315 μm² and 0.188 μm² in 0.25 μm technology. All these features and the small cell size compared to any other flash cell make this device a very attractive solution for all NVM applications     

Discrete quadratic curvature energies

We present a family of discrete isometric bending models (IBMs) for triangulated surfaces in 3-space. These models are derived from an axiomatic treatment of discrete Laplace operators, using these operators to obtain linear models for discrete mean curvature from which bending energies are assembled. Under the assumption of isometric surface deformations we show that these energies are quadratic in surface positions. The corresponding linear energy gradients and constant energy Hessians constitute an efficient model for computing bending forces and their derivatives, enabling fast time-integration of cloth dynamics with a two- to three-fold net speedup over existing nonlinear methods, and near-interactive rates for Willmore smoothing of large meshes.     

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.     

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.     

Neural network principal components preprocessing and diffraction tomography

The use of principal component analysis in preprocessing neural network input data is explored. Four preprocessing schemes are compared in an example problem, and the theoretical basis for the results are discussed. A preconditioning method for the principal components is introduced here, combining normalisation and improved conditioning. The techniques are applied to an object location problem in diffraction tomography. The spectral analysed scattered field from an irradiated object form the input to a Multilayer Perceptron neural network, trained by backpropagation to calculate the coordinates of the object's centre in 2D.Aspects of this work were presented at the NCAF Symposium, King's College London, 9 January 1992.     

Enzymic browning in green olives and its prevention

The browning of green olives, which results from mechanical injury, was followed by measuring the reflectance from the fruit surface at 545 nm. The process is enzymic, apparently catalysed by catechol oxidase. It could not be prevented by inhibitors of the enzyme or by reducing agents, due to the impermeability of the whole fruit to these compounds. Dipping the fruit in 0.4 % NaOH prevented the formation of brown spots following mechanical injury.     

A method for evaluating the use of the polygraph in a real-life situation.

15 males (mean age 29.2 yrs) participated in an experiment to evaluate the polygraph in a real-life situation; 2 Ss had actually cheated on a test. All Ss went through a standard polygraph test using the control questions method. This procedure guarantees the objective identification of "liars" without jeopardizing the real-life appearance of the experimental situation. Each S was evaluated by 3 polygraphers: One had access to the polygraph charts only, one observed the S's behavior but not his charts, and a third had both kinds of information. The evaluations of all 3 polygraphers were compared with the criterion. Evaluations based on both behavior observation and physiological charts were superior to those based on either type of information alone. However, evaluations based on the physiological information alone were not superior to those based on the behavioral information alone. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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.