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Recall that a current will reflect when there are changes in the electrical properties of the material. In order to efficiently send the signal into the transmission line, it is important that the transmission line has the same impedance as the elements, otherwise some of the signal will be reflected back into the antenna. This leads to the concept of impedance matching, the design of the overall system of antenna and transmission line so the impedance is as close as possible, thereby reducing these losses. Impedance matching between antennas and transmission lines is commonly handled through the use of a balun, although other solutions are also used in certain roles. An important measure of this basic concept is the standing wave ratio, which measures the magnitude of the reflected signal.

How is this process usually used for transmission lines and antennas?
Answer: balun
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In his 1854 book "The Cruise of the Steam Yacht North Star" John Choules described Southampton thus: "I hardly know a town that can show a more beautiful Main Street than Southampton, except it be Oxford. The High Street opens from the quay, and under various names it winds in a gently sweeping line for one mile and a half, and is of very handsome width. The variety of style and color of material in the buildings affords an exhibition of outline, light and color, that I think is seldom equalled. The shops are very elegant, and the streets are kept exceedingly clean."

Who wrote "The Cruise of the Steam Yacht North Star"?
Answer: John Choules
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Between 2000 and 2004 an average of 478 crimes were reported each day in Mexico City; however, the actual crime rate is thought to be much higher "since most people are reluctant to report crime". Under policies enacted by Mayor Marcelo Ebrard between 2009 and 2011, Mexico City underwent a major security upgrade with violent and petty crime rates both falling significantly despite the rise in violent crime in other parts of the country. Some of the policies enacted included the installation of 11,000 security cameras around the city and a very large expansion of the police force. Mexico City has one of the world's highest police officer-to-resident ratios, with one uniformed officer per 100 citizens.

What is one way the city tried to combat crime?
Answer:
installation of 11,000 security cameras