The paper presents a new analytical saturation throughput model of IEEE 802.11 DCF (Distributed Coordination Function) with basic access in adhoc mode. The model takes into account freezing of the backoff timer when a station senses a busy channel. It is shown that taking into account this feature of DCF is important in modeling saturation throughput – yields more accurate results than models k...

In this paper, we propose a novel contention-based protocol, called Reservation with Grouping Stations (RGS) for the IEEE 802.11 Distributed Coordination Function (DCF). In the proposed RGS scheme, stations are grouping into the active group, the ready group, and the idle group. Furthermore, stations announce the next frame’s backoff counter beforehand. The proposed scheme is compared with the ...

Adenosine deaminase (ADA) deficiency has been reported in association with severe combined immunodeficiency disease (SCID). The mechanism by which ADA deficiency causes immune dysfunction has been investigated in model systems to which the ADA inhibitor deoxycoformycin (dCf) had been added. Previously, we demonstrated that dCF did not prevent proliferation and differentiation of myeloid and lym...

We demonstrate the application of Nuisance Attribute Projection (NAP), Within-Class Covariance Normalization (WCCN), a new standard kernel, and keyword weighting for the keywordbased HMM supervector speaker recognition system. On our development set (SRE04 8-side training), we achieve 22.6% and 16.2% EER improvements using NAP and WCCN respectively, a 19.5% EER improvement using NAP and WCCN jo...

Cr(VI) genotoxicity is caused by products of its reductive metabolism inside the cells. Reactive oxygen species (ROS) and Cr(V,IV) intermediates are potential sources of oxidative damage by Cr(VI). Here, we investigated seven fluorescent probes for the detection of ROS and non-ROS oxidants in Cr(VI) reactions with its main reducers. We found that Cr(V)-skipping metabolism of Cr(VI) by ascorbate...

In this paper the analysis of Stimulated Raman Scattering induced crosstalk in Subcarrier Multiplexed WDM system has been discussed. The expression for SRS induced crosstalk have been observed for different fiber types such as single mode fiber, dispersion compensation fiber, non-zero dispersion shifted fiber and non-zero dispersion fiber. Comparison of different fibers is done at varying trans...

Large-scale wireless LAN systems based on the IEEE 802.11 standards have become the most successful wireless networks deployed in large organizations, such as educational campuses and corporate warehouses. However, the suite of IEEE 802.11 MAC protocols, including DCF, PCF and EDCA mechanisms, was unable to meet the challenges to provide collision freedom and differentiated quality of services....

A miniature high-sensitivity, high-temperature fiber sensor with an interferometer based on a bare small-core-diameter dispersion compensation fiber (DCF) is reported. The sensing head is a single-mode-fiber (SMF) DCF configuration formed by a 4 mm long bare DCF with one end connected to the SMF by a fusion splicing technique and the other end cleaved. Due to the large mode index difference and...

[Purpose] The purpose of the present study was to examine the amount of change in the thicknesses of the deep cervical flexor (DCF) and sternocleidomastoid (SCM) muscles in subjects with neck pain and subjects without neck pain during craniocervical flexion exercise (CCFE). [Subjects] The total number of subjects was 40, comprising 20 in the no-pain group (males 11, females 9) and 20 in the pai...

IEEE 802.11a is one of the latest standards to be released by the IEEE Project 802. It has specified a new physical layer (PHY) to support higher data rates, known as the orthogonal frequency division multiplexing (OFDM). One of the medium access approaches adopted in the IEEE 802.11 specification is called distributed coordination function (DCF). DCF is a carrier sense multiple access with col...