Knot (unit) fluids (tidal streams, river currents and wind speeds) are also measured in knots. Thus, speed over the ground (SOG) (ground speed (GS) in aircraft) and rate of progress towards a distant point ("velocity made good", VMG) are also given in knots. Until the mid-19th century, vessel speed at sea was measured using a chip log. This consisted of a wooden panel, attached by line to a reel, and weighted on one edge to float perpendicularly to the water surface and thus present substantial resistance to the water moving around it. The chip log was cast over the stern of the
Wind power in Thailand energy by developing renewable energy sources in Thailand, including wind power. The first study of Thai wind energy potential was conducted in 1975 by the Department of Energy Development and Promotion, which is now called the Department of Alternative Energy Development and Efficiency (DEDE). Data of mean wind speed from the Thai Meteorological Department (TMD) was used to produce a wind map of areas with medium to high potential. Later, in 1981, King Mongkut's Institute of Technology Thonburi (KMITT) and King Mongkut's Institute of Technology North Bangkok (KMITNB), in cooperation with Electricity Generating Authority of Thailand (EGAT), produced another wind