题干

如图所示,甲、乙、丙三个逻辑电路的符号分别表示
 

A:“与”门、“或”门、“非”门

B:“与”门、“非”门 、“或”门

C:“或”门、“与”门、“非”门

D:“或”门、“非”门 、“与”门

上一题 下一题 0.0难度 选择题 更新时间:2019-11-05 05:45:55

答案(点此获取答案解析)

A

同类题1

阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项。

    Settled by the Celts, invaded by the Romans and the Normans, and ruled by the English, Wales' population has regularly changed over the ages. Wales, particularly South Wales, became a melting pot (熔炉) of European nationalities and cultures. At first workers from England, Ireland and the rural areas of Wales rushed into the coal mines of South Wales. By 1911, workers from Ireland, Italy and Spain had joined the industrial workforce (劳动大军) there. Many of these newcomers were prepared to work for less pay.

    But during this period, workers, dissatisfied with regular pay cuts, poor safety, returned to the land. In 1891, the rural population of Wales was about 616,000 and by 1911 just over 649,000 people lived and worked in these areas.

       The rural population continues to grow slowly even today. People from richer parts of the UK, particularly southern England, are buying holiday homes in Wales. In some areas this has led to a lack of housing for local people. This, combined with the lack of employment in rural Welsh communities, has started a new movement of people in search of jobs and homes into the towns and cities of Wales and to other parts of the UK and Europe.

    As so many Welsh people have moved to other countries over the last 200 years, it's really no surprise that many visitors come to see friends and relatives. These visitors strengthen their links to their land of origin and continue to support the Welsh's development. During the hot summer days, about 28% of the visitors visit the countryside and nearly 70% visit the seaside.

同类题3

阅读下面的文字,完成后面下列各题。

    虚和实的问题,这是一个哲学宇宙观的问题。这可以分成两派来讲。一派是孔孟,一派是老庄。老庄认为虚比实更真实,是一切真实的原因,没有虚空存在,万物就不能生长,就没有生命的活跃。儒家思想则从实出发,如孔子讲“文质彬彬”,一方面内部结构好,一方面外部表现好。孟子也说:“充实之谓美。”但是孔、孟也并不停留于实,而是要从实到虚,发展到神妙的意境:“充实而有光辉之谓大,大而化之之谓圣,圣而不可知之之谓神。”圣而不可知之,就是虚:只能体会,只能欣赏,不能解说,不能摹仿,谓之神。所以孟子与老庄并不矛盾。他们都认为宇宙是虚和实的结合,也就是《易经》上的阴阳结合。

    世界是变的,而变的世界对我们最显著的表现,就是有生有灭,有虚有实,万物在虚空中流动、运化,所以老子说:“有无相生”,“虚而不屈,动而愈出。”

    这种宇宙观表现在艺术上,就要求艺术也必须虚实结合,才能真实地反映有生命的世界。中国画是线条,线条之间就是空白。石涛的巨幅画《搜尽奇峰打草稿》(故宫藏),越满越觉得虚灵动荡,富有生命,这是中国画的高妙处。

    以上是虚实问题的一个方面,即思想家认为客观现实是个虚实结合的世界,所以反映为艺术,也应该虚实结合,才有生命。虚实问题的另一个方面,即思想家还认为艺术要主观和客观相结合,才能创造美的形象。这就是化景物为情思的思想。 宋人范文《对床夜语》说:“不以虚为虚,而以实为虚,化景物为情思,从首至尾,自然如行云流水,此其难也。” 化景物为情思,这是对艺术中虚实结合的正确定义。以虚为虚,就是完全的虚无;以实为实,景物就是死的,不能动人;惟有以实为虚,化实为虚,就有无穷的意味,幽远的境界。清人笪重光《画筌》说:“实景清而空景现”“真境逼而神境生”“虚实相生,无画处皆成妙境”。清人邹一桂《小山画谱》说:“实者逼肖,则虚者自出。”这些话也是对虚实结合的很好说明。艺术通过逼真的形象表现出内在的精神,即用可以描写的东西表达出不可以描写的东西。

    化景物为情思、虚实结合,在实质上就是一个艺术创造的问题。艺术是一种创造,所以要化实为虚,把客观真实化为主观的表现。清代画家方士庶说:“山川草木,造化自然,此实境也;画家因心造境,以手运心,此虚境也。虚而为实,在笔墨有无间。”(《天慵庵随笔》)这就是说,艺术家创造的境界尽管也取之于造化自然,但他在笔墨之间表现了山苍木秀、水活石润,是在天地之外别构一种灵奇,是一个有生命的、活的,世界上所没有的新美、新境界。凡真正的艺术家都要做到这一点,虽然规模大小不同,但都必须有新的东西、新的体会、新的看法、新的表现,他的作品才能丰富世界,才有价值,才能流传。

摘编自宗白华《美学与意境》