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Independent Operation (independent + operation)

Distribution by Scientific Domains

Information Science and Computing	50%

Selected Abstracts

Role of glial amino acid transporters in synaptic transmission and brain energetics

GLIA, Issue 3 2004
Païkan Marcaggi
Abstract This article reviews how the uptake of neurotransmitter by glial amino acid transporters limits the spatial spread of transmitter to preserve the independent operation of nearby synapses, temporally shapes postsynaptic currents, and regulates the effects of tonic transmitter release. We demonstrate the importance of amino acid uptake and recycling mechanisms for preventing the loss of energetically costly neurotransmitter from the brain, and also examine the suggestion that glutamate uptake into glia plays a key role in regulating the energy production of the brain. Finally, we assess the role of glial amino acid transporters in transmitter recycling pathways. © 2004 Wiley-Liss, Inc. [source]

An artificial neural network based approach for online string matching/filtering of large databases,

INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 4 2010
Tatiana Tambouratzis
A novel online approach to exact string matching and filtering of large databases is presented. String matching/filtering is based on artificial neural networks and operates in two stages: initially, a self-organizing map retrieves the cluster of database strings that are most similar to the query string; subsequently, a harmony theory network compares the retrieved strings with the query string and determines whether an exact match exists. The similarity measure is configured to the specific characteristics of the database so as to expose overall string similarity rather than character coincidence at homologous string locations. The experimental results demonstrate foolproof, fast, and practically database-size independent operation that is especially robust to database modifications. The proposed approach is put forward for general-purpose (directory, catalogue, glossary search) as well as Internet-oriented (e-mail blocking, URL, username classification) applications. © 2010 Wiley Periodicals, Inc. [source]

A query language for discovering semantic associations, Part II: sample queries and query evaluation

JOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 11 2007
Timo Niemi
In our query language introduced in Part I (Niemi & Jämsen, in press) the user can formulate queries to find out (possibly complex) semantic relationships among entities. In this article we demonstrate the usage of our query language and discuss the new applications that it supports. We categorize several query types and give sample queries. The query types are categorized based on whether the entities specified in a query are known or unknown to the user in advance, and whether text information in documents is utilized. Natural language is used to represent the results of queries in order to facilitate correct interpretation by the user. We discuss briefly the issues related to the prototype implementation of the query language and show that an independent operation like Rho (Sheth et al., 2005; Anyanwu & Sheth, 2002, 2003), which presupposes entities of interest to be known in advance, is exceedingly inefficient in emulating the behavior of our query language. The discussion also covers potential problems, and challenges for future work. [source]

MMIC PAM applied with pre-distorter having independent operation of nonlinear signal

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2008
Inn-Yeal Oh
Abstract A dynamic pre-distorter with two paths to set nonlinear signal level and phase encourages power amplifier module (PAM) for wireless broadband (Wibro) service to enhance linearity. We proposed a linearizer having a new IM generator, which is made up of the InGaP/GaAs HBT operated at saturation region of a common collector circuit. The targeted Wibro PAM is designed using InGaP/GaAs HBT technology, and the pre-distorter, drive and power amplifier are fully integrated in single chip within 960 × 2400 ,m. Even though PAM is designed to have just a 5-dB back-off, PAM is compatible with linearity standards up to maximum output power 21 dBm, and has a 17.5% efficiency by having a low leakage and improving spurious of 6 dB in the 64QAM form based on IEEE802.16e-2005 standards. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 851,855, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23235 [source]