We argue that “effective” superluminal travel, potentially caused by the tipping over of light cones in Einstein gravity, is always associated with violations of the null energy condition (NEC). This is most easily seen by working perturbatively around Minkowski spacetime, where we use linearized Einstein gravity to show that the NEC forces the light cones to contract (narrow). Given the NEC, t...

This research work was based on an experimental concept of functional clothing for children with psychomotor development limitations. No matter the analyzed pathology, all these children need sensorial stimulation because of their psychomotor difficulties, especially at fine motor skills level. The main objective was to develop functional and comfortable clothing with sensorial stimulation elem...

This paper explains why long Distributed Queue Dual Bus (DQDB) networks without bandwidth balancing can have fairness problems when several nodes are performing large file transfers. The problems arise because the network control information is subject to propagation delays that are much longer than the transmission time of a data segment. Bandwidth balancing is then presented as a simple solut...

We introduce a general non-Gaussian, self-similar, stochastic process called the fractional Lévy motion (fLm). We formally expand the family of traditional fractal network traffic models, by including the fLm process. The main findings are the probability density function of the fLm process, several scaling results related to a singleserver infinite buffer queue fed by fLm traffic, e.g., scalin...

I develop a novel model of team/committee decision making in which communication is costly in two directions: agents must pay costs to send messages to one another, but also to receive messages sent by others. Agents are heterogeneous only in the quality of the information they possess, and preferences are directly aligned over outcomes. Equilibrium strategies are intuitively characterized by a...

The combination of higher quality requirements and sensitivity of high performance circuits to delay defects has led to an increasing emphasis on delay testing of VLSI circuits. As delay testing using external testers requires expensive ATE, built-in self test (BIST) is an alternative technique that can significantly reduce the test cost. It has been proven that Single Input Change (SIC) test s...

Humans frequently need to allocate resources across multiple time-steps. Economic theory proposes that subjects do so according to a stable set of intertemporal preferences, but the computational demands of such decisions encourage the use of formally less competent heuristics. Few empirical studies have examined dynamic resource allocation decisions systematically. Here we conducted an experim...

We propose a simple queueing model for TCP transfers sharing a bottleneck link and examine its behavior when the buffer at the bottleneck is large compared to the bandwidth-delay product. This model explains some behaviors of TCP that have already been observed, and predicts other behaviors that are new. We present measurements that demonstrate these behaviors in the current Internet.

AIM Several behavioural correlates of self-injury, aggression and destructive behaviour have been identified in children and young adults with intellectual disabilities. This cross-sectional study aimed to further explore these correlates in very young children with developmental delay. METHODS Parents of 56 children (40 male) under the age of five years (mean age 2 years 10 months) completed...

The goal of this paper is to increase our understanding of the fundamental performance limits of urban vehicle networks by exploiting the self-similarity and hierarchical organization of modern cities. We use an innovative model called “hyperfractal” that captures the self-similarity of the topology and vehicle locations while avoiding the extremes of regularity and randomness. We use analytica...