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Wireless Personal Communications: A Perspective
Published in Jerry D. Gibson, The Communications Handbook, 2018
Consider first a cordless telephone base unit. The cordless base-unit transceiver usually serves one or, at most, two handsets at the end of one wireline loop. Now consider moving such a base unit back along the copper-wire-pair loop end a distance that can be reliably covered by a low-power wireless link [25,31], i.e., several hundred to a thousand feet or so, and mounting it on a utility pole or a street light pole. This replaces the copper loop end with the wireless link. Many additional copper loop ends to other subscribers will be contained within a circle around the pole having a maximum usable radius of this wireless link. Replace all of the copper loop ends within the circle with cordless base units on the same pole. Note that this process replaces the most expensive parts of these many loops, i.e., the many individual loop ends, with the wireless links from cordless handsets to "equivalent" cordless base units on a pole. Of course, being mounted outside will require somewhat stronger enclosures and means of powering the base units, but these additional costs are considerably more than offset by eliminating the many copper wire drops.
P
Published in Philip A. Laplante, Comprehensive Dictionary of Electrical Engineering, 2018
The pole-coefficient sensitivity is frequently used in evaluation of active circuit stability. pole-top transformer generally a distribution transformer which is mounted atop a utility pole near the customer. pole-zero plot a graphical representation of a Laplace transform is known as a pole-zero plot. Except for a scale factor, the numerator and denominator polynomials in a rational Laplace transform X (s) = N (s)D(s) can be specified by their roots. Thus, marking the location of the roots of N (s) and D(s) in the s-plane provides a powerful way of visualizing a Laplace transform. Pole-zero plots are used extensively in signal processing design and analysis, e.g., to determine the stability of a system function. polled interrupt a mechanism in which the CPU identifies an interrupting device by polling each device. See also vectored interrupt. polling sequencing through a group of peripheral devices and checking the status of each. This
Condition assessment tool for timber utility poles using stress wave propagation technique
Published in Nondestructive Testing and Evaluation, 2021
B. Sriskantharajah, E. Gad, S. Bandara, P. Rajeev, I. Flatley
Six hundred timber utility pole results collected from Christchurch are individually analysed. A timber utility pole is normally expected to be in service for around 40–50 years without failure from natural deterioration, however ageing of poles can change the properties of the material. Therefore, it is important to investigate the change of SWP velocity within the service life period of a utility pole. Figure 14 shows a plot of the transverse SWP velocity against the installation year regardless of the pole species, height and diameter. From Figure 14, it is clear that there are slight changes in average transverse SWP velocity based on the year of installation. The SWP velocity is considered to be the same for a pole, as the material properties of an in-service timber pole do not change significantly with time to make a substantial difference in the SWP velocity. The transverse SWP velocity is related only to the material properties of the pole. Nevertheless, there are different stress wave propagation velocities even within the poles installed in the same year since different pole species are considered for this analysis. Figures 15 and 16 show that the length and diameter have an insignificant effect on the transverse SWP velocity of a timber utility pole. The referred diameter of poles for Figure 16 is measured at ground level.
A review on condition assessment technologies for power distribution network infrastructure
Published in Structure and Infrastructure Engineering, 2023
Sahan Bandara, Pathmanathan Rajeev, Emad Gad
Utility poles are used in power distribution networks to support overhead cables and other attachments. Similar to cross-arms, predominant source of utility poles are wood. However, alternate materials such as steel, concrete, and composites are also being used. Typical service life of a hardwood or softwood timber utility pole is around 40–60 years. Evaluation of the structural integrity of poles is essential thorough out the service life in order to identify potential defects and to estimate the residual strength. A wide range of condition assessment techniques are employed by asset managers for the routine inspection of in-service poles. Figure 4 shows the categorisation of these condition assessment techniques.