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...

Diclofenac (DCF) is a well-known and widely used non-steroidal anti-inflammatory drug (NSAID), with a range of actions which are of interest in an oncological context. While there has long been an interest in the use of NSAIDs in chemoprevention, there is now emerging evidence that such drugs may have activity in a treatment setting. DCF, which is a potent inhibitor of COX-2 and prostaglandin E...

Here we propose a model on EnhancedLarge Effective Area Fiber (E-LEAF) and Dispersion Compensation Module (DCM) with precise designed Dispersion Compensation Fiber (DCF). The Model is implemented in a long haul Single and Multichannel Optical telecommunication systems with E-LEAF as data transmission Fiber (NZ-DSF) of 1700Km (85 Km SMF×20 loops) length. The DCM is proposed in Symmetric Compensa...

IEEE 802.11 is the most popular standard used in WLAN. Distributed Coordination Function (DCF) is one of the channel-access methods in the IEEE 802.11 Medium Access Control (MAC) protocol. However, It has not been adequately studied under the existence of hidden stations. In the paper, we present the novel saturated throughput analysis of the IEEE 802.11 DCF in the presence of hidden stations. ...

In this work, we propose a hybrid medium access scheme that can provide a virtually collision-free environment for an infrastructure high-speed WLAN. The proposed hybrid scheme may be viewed as the merger of the standard PCF and DCF schemes. It can efficiently provide the quality-of-service support like the PCF scheme, while utilizing the flexible on-demand CSMA mechanism similar to the DCF sch...

Although the performance analysis of the IEEE 802.11 Distributed Coordination Function (DCF) in saturation state has been extensively studied in the literature, little work is present on performance analysis in non-saturation state. In this paper, a simple model is proposed to analyze the performance of IEEE 802.11 DCF with service differentiation support in non-saturation states, which helps t...

This paper describes a technique for clustering large collections of short and medium length text documents such as press articles, news stories and the like. The technique called description comes first (DCF) consists of identification of related document clusters, selection of salient phrases relevant to these clusters and reallocation of documents matching the selected phrases to form final ...