Early Electronic Computers The first real progress toward electronic digital computer came in the late 1930s when Howard Aiken of Harvard University and George Slibits of Bell Telephone Laboratories developed an automatic calculator using relay networks;the relay is an electromagnetically controlled Other relay machines were developed during World War II for artillery ballistic Although these machines were relatively slow and comparatively they demonstrated the versatility of the electronic Then，in the early 1940s， John Mauchly and JPresper Eckert，J，of the University of Pennsylavania designed and built a vacuum tube computer，which they called the electronic numerical inegrator and calculator(ENIAC);it was completed in 1945 and installedat Aberdeen Proving Ground，M ENIAC used 18000 electron tubes，which required tremendous amounts of power;its failure rate wa high and it was difficult to program because a plugboard was Three very important discoveries were then made，which began the rapid evolution toward today's digital First，John von Neumann proposed that the program reside in the computer's memory where it could be changed at will，solving the pogranmming difficulties of ENIAC;second，in 1947 the transistor was invented by John Bradeen，Waltr HBrattain， and William Shockley，which drastically reduced the size and power requirements by replaceing the electron vacuum tube;hird， JWForrester and his associates at the Massachusetts Institute of Technology developed the magnetic，core memory，which made large amount of storage Reference book: Digital Logic Circuit Analysis and Design(Authors:Victor PNelson HTroy Nagle JDavid Irwin)
写作思路：根据为科技主题，以为发展基调来展开描写，紧扣叙述与描写的内容，力求做到不突兀、不生硬，不长篇大论或肆意抒情，有情真意切之感。范文：It can be expected that there will be a breakthrough in life sceience and space science in the 21st century First， scientists will conquer incurable diseases through the transformation of genes可以预见，21世纪生命科学和空间科学将取得突破性进展。首先，科学家将通过基因转化来战胜不治之症。With the same technology they can breed new species of animals and even human life in the laboratory Most important of all， they can decelerate aging and prolong life用同样的技术，他们可以在实验室培育出新的动物物种，甚至人类的生命。最重要的是，它们能延缓衰老，延长寿命。Besides， permanent stations will be set up in the moon or other planets or stars so that scientists can make a thorough study of the moon and other planets or star此外，还将在月球或其他行星或恒星上建立永久观测站，以便科学家对月球和其他行星或恒星进行深入研究。扩展资料英语想写好作文，必须具备扎实的基本功，作文的基本功主要体现在词、句、段三个方面。单词方面，积累单词，扩大词汇量，弄清词的确切用法及相似词的用法区别，以及很多固定短语、习语的用法，要准确地表达想要表达的意思。句子方面，注意一些常用的句式，平时看到比较好用的句式要记下来，多模仿，还要在写文章时注意长短句的结合。段落方面，注意整篇文章的整体布局，要从整体上把握每段的中心思想，避免偏题、走题。提高写作水平不是一朝一夕所能完成的，最重要的是养成好的学习习惯，平时注意多积累，勤动笔、多思考，潜移默化中写作水平便会不断提高。
Nowadays， technology is everywhere around The development of technology has a significant affact toward the Several technologies that we usually use are the internet， computer， and These new technologies make our life much easier and First， the development of computer changes our Decades ago， people needed to do lots of complex calculation on hand because they did not have computer， and more obvious， they did not have the software for As the result of that， people spent hours on the equations that a computer can solve in just a Since the development of computer， people are able to use some kind of software to compute lots of complex functions and mathematical Computer becomes the most helpful equipment for the sciencists because they can use their time more In conclusion， I believe the development of technology brings significant impact to our It is very helpful to us and I believe technology will keep improving in
The new century is It can be expected that there will be a breakthrough in life sceience and space science in the 21st First， scientists will conquer incurable diseases through the transformation of With the same technology they can breed new species of animals and even human life in the Most important of all， they can decelerate aging and prolong Besides， permanent stations will be set up in the moon or other planets or stars so that scientists can make a thorough study of the moon and other planets or Most probably life will be found in other stars in universe or the planets or stars suitable for the human existence will be However， the scientific development will also bring about some social How should we regard from an ethical perspective the one who is bred through the gene technology in the How can the police identify the criminal from a group of people with the same DNA? It is quite natural that we will meet problems in the scientific and social Therefore， we should be prepared to meet new 汇众动漫学院
