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1 美国Dialog系统 1.1 Dialog系统概况 Dialog系统建立于1963～1964年间,原为美国洛克希德导弹与航空公司的子公司经营,是目前美国和世界上最大的联机检索系统。该系统总部设在美国加利福尼亚州的帕洛·阿尔托市(Palo·Alto)。后因研制Dialog人机对话情报检索软件而得名。1981年6月,Dialog系统正式宣布独立,成为洛克希德公司中的24个子公司之一,直属洛克希德总公司并开始独立经营。1988年10月,美国洛克希德公司又将Dialog系统以3.5亿美元卖给美国的Knight-Ridder公司。 Dialog系统于1966年正式开展文献检索。当时该系统与美国国家宇航局(NASA)的研究实验室图书馆合作,通
1 Dialog System 1.1 Introduction to Dialog System The Dialog system was established between 1963 and 1964. It was originally operated by a subsidiary of the U.S. Lockheed missiles and airlines and is currently the largest online search system in the United States and the world. The system is headquartered in Palo Alto, California, USA. After the development of Dialog man-machine dialogue information retrieval software named. In June 1981, Dialog officially announced its independence as one of Lockheed’s 24 subsidiaries, headquartered in Lockheed and began operating independently. In October 1988, the United States Lockheed Company in turn sold the Dialog system to Knight-Ridder in the United States for 350 million U.S. dollars. Dialog system was officially launched in 1966 literature search. At that time the system and the United States NASA research laboratory library, through