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Machine vision systems often require bright and homogeneous illumination, so features of interest are easier to process. LEDs are often used for this purpose, and this is likely to remain one of their major uses until the price drops low enough to make signaling and illumination uses more widespread. Barcode scanners are the most common example of machine vision, and many low cost products use red LEDs instead of lasers. Optical computer mice are an example of LEDs in machine vision, as it is used to provide an even light source on the surface for the miniature camera within the mouse. LEDs constitute a nearly ideal light source for machine vision systems for several reasons:
What is the most common example of a machine vision system?
A: Barcode scanners

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Jim Foster, a promotions manager with the National Football League, conceived of indoor football while watching an indoor soccer match at Madison Square Garden in 1981. While at the game, he wrote his idea on a 9x12 envelope, with sketches of the field and notes on gameplay. He presented the idea to a few friends at the NFL offices, where he received praise and encouragement for his concept. After solidifying the rules and a business plan, and supplemented with sketches by a professional artist, Foster presented his idea to various television networks. He reached an agreement with NBC for a "test game".
Where was Jim Foster when he came up with the idea for arena football?
A: Madison Square Garden

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State banquets also take place in the Ballroom; these formal dinners are held on the first evening of a state visit by a foreign head of state. On these occasions, for up to 170 guests in formal "white tie and decorations", including tiaras, the dining table is laid with the Grand Service, a collection of silver-gilt plate made in 1811 for the Prince of Wales, later George IV. The largest and most formal reception at Buckingham Palace takes place every November when the Queen entertains members of the diplomatic corps. On this grand occasion, all the state rooms are in use, as the royal family proceed through them, beginning at the great north doors of the Picture Gallery. As Nash had envisaged, all the large, double-mirrored doors stand open, reflecting the numerous crystal chandeliers and sconces, creating a deliberate optical illusion of space and light.
Where do state banquets take place?
A: in the Ballroom

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A second New Haven gastronomical claim to fame is Louis' Lunch, which is located in a small brick building on Crown Street and has been serving fast food since 1895. Though fiercely debated, the restaurant's founder Louis Lassen is credited by the Library of Congress with inventing the hamburger and steak sandwich. Louis' Lunch broils hamburgers, steak sandwiches and hot dogs vertically in original antique 1898 cast iron stoves using gridirons, patented by local resident Luigi Pieragostini in 1939, that hold the meat in place while it cooks.
Louis' Lunch is popular for serving what?
A:
the hamburger