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A few days ago, the Consumer Electronics Survey Office of the China Electronic Chamber of Commerce released the "Research on the Screen Size and Viewing Distance of Color TVs" at the United Nations Radio and TV Products Quality Supervision and Inspection Center. The results show that since the era of flat-panel TVs, the choice of viewing distance and TV size has always influenced consumer purchasing decisions. For the purchase of high-definition television (HD), the International Radio Consultative Committee has previously recommended the relevant reference: the best viewing distance is 3 times the height of the color TV screen. For a long time, the home appliance store shopping guide is also based on this criteria to recommend to consumers. However, when flat-panel TVs are upgraded to full HD (FHD), the screen resolution is higher, the image display is more delicate, and the relationship between the optimal viewing distance and the TV screen size also changes.
Recently, the National Radio and TV Product Quality Supervision and Inspection Center, the Consumer Electronics Product Survey Office of the China Electronic Chamber of Commerce, and mainstream TV manufacturers, such as Skyworth, have targeted mainstream Full HD TVs in the market according to the limits of human vision, flat panel TV screens, and home viewing environments. Dimensions have been related to the research and the results show that: In general, home-purchased full-HDTVs are ideal for watching 55-inch images without the need for full-HD image information.
These controllers eliminated the need for rewiring and adding additional hardware for each new configuration of logic.
The new system drastically increased the functionality of the controls while reducing the cabinet space that housed the logic.
The first PLC, model 084, was invented by Dick Morley in 1969.The first commercial successful PLC, the 184, was introduced in 1973 which was designed by Michael Greenberg.