祖魯時間與全球分區

Zulu Time and the World-wide Zoning

時間是測量之一項基本元素，除距離量測中可以量度時間差，乘以光速得距離，等量度面向外，由於地球自轉，日常計時之時間與地理座標中之經度關係密切。就時間標記而言，GPS相關之公告中常見UTC及Zulu（祖魯），本文僅就其涵意與歷史背景提供說明，並由此討論全球依照經緯度之分區系統，包含Bowditch分區與UTM分區。 Time is an important subject in surveying. Besides applications such as using time difference to compute distance with electromagnetic wave speed, time is related to longitude because of the earth rotation. UTC and Zulu are commonly seen in announcement related to GPS. This article explains the meaning and historic background of Zulu time. Two world-wide zoning systems based on the latitude and longitude, Bowditch and UTM, are also described.

Time is an important subject in surveying. Besides applications such as using time difference to compute distance with electromagnetic wave speed, time is related to longitude because of the earth rotation. UTC and Zulu are commonly seen in announcement related to GPS. This article explains the meaning and historic background of Zulu time. Two world-wide zoning systems based on the latitude and longitude, Bowditch and UTM, are also described.