Multimedia and real-time applications require bandwidth guarantees, which may be achieved by resource reservation. Several researches were done to propose efficient reservation MAC protocols for ad-hoc networks. In these schemes, channel is segmented into super-frames composed of fixed number of slots. They allocate slots to each traffic source, and make sure that neighbor nodes record the rese...

The designs of dual band microstrip patch antennas because of their multi-functionality are becoming popular. Satellite mobile and fixed communication for Space Research, Met. Satellite, Radiolocation, Meteorological aids, aeronautical Radio navigation data and analysis has got lot of attentions in the recent years. Achieving selected multiband operation requires precise bandwidth and mutually ...

Local scouring around bridge piers is a natural phenomenon caused by the erosive process of flowing stream on alluvial beds. The 3D flow field around bridge piers interacting with the bed materials increases complexity of local scour process. The local scour depth develops in accelerated flows and if it is not predicted correctly, the bottom level of local scour hole will exceed the original le...

The design of an efficient Medium Access Control (MAC) is challenging in ad-hoc networks where users can enter, leave or move inside the network without any need for prior configuration. Chlamtac and Farago have proposed a topology unaware TDMA-based scheme, suitable for ad-hoc networks, while Ju and Li have proposed an enhanced version that maximizes the minimum guaranteed throughput. Both app...

BACKGROUND The aim of this study is to calculate and compare the play and torque expression of 0.018 and 0.022 bracket slots when engaged with archwires of different size, cross section and material. METHODS Eight orthodontic brackets, two of slot height 0.018 and six of slot height 0.022, from different manufacturers, were measured and fixed to a vertical support. Twenty-four archwires of di...

We investigate a scheduling problem in a TDMA environment where packets may be fragmented. Our model of the problem is derived from a scheduling problem present in data over CATV networks, where a slotted TDMA channel is used to carry both real-time and best-effort traffic. Packets of real-time flows have high priority and are allocated in fixed, periodically located slots. Best-effort packets ...

Frame slotted ALOHA (FSA) protocol is a classic tag anti-collision protocol. Similar to most existing anti-collision protocols, The FSA initially aims at tag identification of static scenarios, that is, all tags keep still during the tag identification process. However, in many real scenarios, tags generally move along a fixed path in the reader coverage area, that is, tags stay the coverage ar...

Let T = τ + 1/C, where τ is the fixed propagation delay. Divide the time into intervals of T , starting from time t = 0. We number the intervals, starting from interval 0. Let the interval n be [nT, (n + 1)T ), for n = 0, 1, 2, .... Let us further divide each interval into identical time slots, each of which is equal to the transmission time of a fixed-size packet, 1/C. We assume CT is an integ...

This paper studies the enhanced efficiency of the field strength coupled into slots by using the finite difference time domain method. The coupled field strength with the different slots shape, size, and polarization direction is assisted, some useful rules are concluded. The easiest to form enhanced efficiency of field strength is rectangular slots, square slots are the second, and the most di...