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Processing Delays (processing + delay)

Distribution by Scientific Domains

Engineering	60%
Psychology	40%

Selected Abstracts

Gateway performance for network-controlled WLAN IP mobility

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 12 2007
Moshiur Rahman
Abstract ,Always on' broadband-accessed network gateway (GW) control can facilitate inter-WLAN IP mobility, with seamless connectivity. The GW server plays a critical role in the overall WLAN IP (WIP) mobility architecture (IEEE Wireless Communications and Networking Conference, WCNC, Atlanta, GA, 21 March 2004; Int. J. Wireless Inf. Networks 2006; 13(3):173,192). This paper provides a comparison of WIP with cellular IP (CIP) and mobile IP (MIP), and identifies the main requirements for a broadband-accessed network-based GW that supports WIP mobility. The paper then evaluates GW-contributed handoff message processing delay in the WIP architecture through an analytical system model and OPNET simulation model, and provides a comparison of the GW-contributed handoff message processing delays for non-preemptive vs preemptive queuing schemes. Both analytical and simulation results show that WIP handoff message processing delay at the GW has negligible impact on the overall system delay. Finally, this paper presents the simulation results of the fast routing table lookup and forwarding speed on the GW overall performance, which can assist service providers in the challenging implementation issues that they face. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Mere presence of distractors: Another determining factor for the attentional blink1

JAPANESE PSYCHOLOGICAL RESEARCH, Issue 3 2003
Jun-Ichiro Kawahara
Abstract: When two visual targets are presented in rapid succession, perception of the second target is deteriorated if the temporal lag between the two targets is short (0,300 ms). This ,attentional blink' (AB) phenomenon has been believed to occur only when the second target is followed by a backward mask or when there is a task switching between two targets. The present study revealed another determining factor for the occurrence of the AB, the presence or absence of a distractor stream. Five experiments examined the effect of possible confounding factors in the extant literature and suggested that the mere presence of a distractor stream affects the processing of targets even when the observers tried to ignore them, resulting in a processing delay. This effect is discussed in a model of AB deficit in terms of decay of the second target's representation. [source]

Gateway performance for network-controlled WLAN IP mobility

Decentralized control strategies for dynamic routing

OPTIMAL CONTROL APPLICATIONS AND METHODS, Issue 6 2002
ftar
Abstract The routing problem in multi-destination data communication networks is considered. A dynamic model, which can incorporate arbitrary, different, time-varying processing delays at different nodes, is developed to describe the network dynamics. Based on this model, controllers for routing control are proposed. The structures of the proposed controllers are motivated by an optimal control problem. These proposed controllers are completely decentralized in the sense that all necessary on-line computations are done locally at each node. Furthermore, the information needed for these computations is related only to the queue lengths at the present node and the adjacent downstream nodes. Both cases when the controls can be continuously changed and when the controls are updated at discrete time instants are considered. In the latter case the controls at different nodes may be updated at different time instants (i.e. the network is not necessarily synchronous). It is shown that the controllers enjoy many desirable properties; in particular, they clear all the queues of the network in the absence of external message arrivals, in finite time. Furthermore, the controllers do not direct messages around a loop. They also have certain robustness properties. Some simulation results relating to a number of realistic problems are presented to illustrate various features of the controllers. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Intramodal and crossmodal processing delays in the attentional blink paradigm revealed by event-related potentials

PSYCHOPHYSIOLOGY, Issue 5 2008
Alexia Ptito
Abstract In the attentional blink (AB), processing of a second target (T2) is impaired if it is presented shortly after the onset of a first target (T1), leading to a decrease in accurate report of T2 if T2 is masked. Some prominent theories of the AB suggest that an amodal bottleneck in working memory consolidation underlies the AB. We investigated this by factorially manipulating T1 and T2 modalities (visual or auditory) using equivalent stimuli and tasks in both modalities to minimize task switching. T2 was not masked. In all modality combinations, the electrophysiological P3 component to T2, obtained by subtracting T1 only trials from T1+T2 trials, was delayed and reduced in amplitude when T2 was presented soon after T1 relative to when T1 and T2 were presented farther apart. Results provide support for a common amodal bottleneck that underlies the AB effects observed in all visual/auditory modality combinations. [source]