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毕业论文课题相关文献综述一: 相关文献概述施工组织设计是工程建设和指导工程施工的重要文件,是建筑施工企业单位能以高质量、高速度、低成本、少消耗完成工程项目建筑的有力保证措施,也是加强管理、提高经济效益的重要手段,也是很正确处理施工中人员、机器、原料、方法、环境及工艺与设备,土建与安装写作,消耗与供应,管理与成产等各种各样的矛盾,科学合理地、计划而有序地均衡地组织项目施工生产的重要保障。通过施工组织设计的编制,可以全面考虑拟建工程的各种具体施工条件,扬长避短地拟定合理的施工方案,确定施工顺序、施工方法和劳动组织,合理地统筹安排拟定施工进度计划;为拟建工程的设计方案在经济上的合理性,在技术上的利学性和在实施工程上的可能性进行论证提供依据;为建设单位编制基本建设计划
一、研究背景 防潮、防霉、防腐、防爆是仓库日常工作的重要内容,是衡量仓库管理质量的重要指标。它直接影响到储备物资的使用寿命和工作可靠性。为保证日常工作的顺利进行,首要问题是加强仓库内温度与湿度的监测工作。但传统的方法是用与湿度表、毛发湿度表、双金属式测量计和湿度试纸等测试器材,通过人工进行检测,对不符合温度和湿度要求的库房进行通风、去湿和降温等工作。这样不但控制精度低、实时性差,而且操作人员的劳动强度大。即使有些用户采用半导体二极管作为温度传感器,但由于其互换性差,效果也不理想。由于温度过高或过低引起的库存品失效或由于环境湿度过高而引起的事故时有发生,甚至危及到人员的安全。所以实施对温湿度的监控十分重要,同时有利于促进企业管理建设与高新科技的结合,把企业仓库
文 献 综 述 课题的背景: 单片机自问世以来,性能不断提高和完善,其资源又能满足很多应用场合的需要,加之单片机具有集成度高、功能强、速度快、体积小、功耗低、使用方便、价格低廉等特点,因此,在工业控制、智能仪器仪表、数据采集和处理、通信系统、高级计算器、家用电器等领域的应用日益广泛,并且正在逐步取代现有的多片微机应用系统。单片机的潜力越来越被人们所重视。特别是当前用CMOS工艺制成的各种单片机,由于功耗低,使用的温度范围大,抗干扰能力强,能满足一些特殊要求的应用场合,更加扩大了单片机的应用范围,也进一步促使单片机性能的发展。而现在的单片机在农业上页有了很多的应用。随着人们生活水平的不断提高,单片机控制无疑是人们追求的目标之一,它所给人带来的方便也是不可否定的,其中
毕业论文课题相关文献综述文献综述一背景随着煤矿工业现代化程度的提高,煤矿井下监控系统的应用是保证煤矿安全生产的必不可少的措施。由于井下环境非常恶略,监控点分散,检测种类多,测量数量大,通讯距离远,并且对实时性和可靠性要求极高,一般通讯方案无法解决。而CAN总线是近年来发展很快,并且得到广泛应用的一种现场总线,凭借其极高的灵活性、可靠性、可扩展性等优点被广泛应用于控制系统的实时监测采集和反馈执行机构之间的数据通讯中。CAN总线是控制器局域网(ControllerAreaNetwork)总线的简称,是德国Bosch公司在1986年为解决现代汽车中众多测量控制部件之间的数据交换而开发的一种串行数据通讯总线,是一种有效支持分布式控制或实时控制的串行通信网络[1]。已成为ISO国际标准ISO11898。CAN总线可广泛应用于离散控制领域中的
文 献 综 述 1. 压电陶瓷用功率放大器课题背景与意义 压电陶瓷是一能够将机械能和电能互相转换的功能陶瓷材料。压电陶瓷是功能陶瓷中应用极广的一种。日常生活中很多人使用的”电子打火机”和煤气灶上的电子点火器,就是压电陶瓷的一种应用。点火器就是利用压电陶瓷的压电特性,向其上施加力,使之产生十几kV的高电压,从而产生火花放电,达到点火的目的。 压电陶瓷驱动器是一种利用压电材料逆压电效应制作的微驱动器,它是近年来倍受关注的新型精密驱动器,其具有体积小、推力大、定位精度高、分辨率高、频响快等优点,并且不发热,不产生噪声,己成为微机电系统中重要定位及驱动元件,在纳米技术、精密测量、微细加工、微电子和机器人等领域取得了广泛应用。超精密切削加工的压电陶瓷微量进刀机构、压电陶瓷补偿执行
毕业论文课题相关文献综述1. Introduction1.1 Research background F. Scott Fitzgerald (18961940) is an American author of novels and short stories and has been widely acclaimed as one of the twentieth centurys greatest writers. For Fitzgerald, who lived in the midst of the roaring twenties and was part of it alldriving fast cars, drinking hard whisky, and taking a vast delight in it, American was, he was so cognitive to realize, a moon that never rose. As much as he appreciated the bustling of the postwar period, he predicted its gloom andsag. So most of his work centering on the social problems and phenomena of the 20th century have been regarded as important materials for the generation to rethink profoundly of the hidden spiritual crisis and the disillusion of American Dream. Fitzgerald is a prominent spokesman of the Jazz Age, which in the words of Malcolm Cowley, is not so much a historical period as a legend of glitter, of recklessness, and of talent in such profusion th
毕业论文课题相关文献综述2. Literature review2.1 Previous studies on燱uthering HeightsWuthering Heights receives a high evaluation and captures a great attention throughout the whole world. However, it received both praise and criticism when first published. Although it was criticized at that time for it challenged strict Victorian ideals of the day, including religious hypocrisy, morality, social classes and gender inequality, recently it has attracted interests of many scholars. This novel was not popular among Chinese literary circles until the 1980s. Plenty of academic monographs, periodical and academic dissertation sprang up one after another. Chinese scholar, Fang Ping said that Wuthering Heights, an ingenious work, is so classic that it is able to compare favorably with the great plays of Shakespeare. Besides, there are some scholars focusing on the relations between Emily抯 unique life experience and her works. For example, Wang Guoqing抯(1988) 揗ake an analyze
毕业论文课题相关文献综述1. Introduction Jerome David "J. D." Salinger (January 1, 1919 January 27, 2010) was an American writer who won acclaim early in life. He led a very private life for more than a half-century. He published his final original work in 1965 and gave his last interview in 1980. Salinger was raised in Manhattan and began writing short stories while in secondary school. Several were published in Story magazine in the early 1940s before he began serving in World War II. In 1948, his critically acclaimed story "A Perfect Day for Bananafish" appeared in The New York magazine, which became home to much of his later work. In 1951, his novel The Catcher in the Rye was an immediate popular success. His depiction of adolescent alienation and loss of innocence in the protagonist Holden Caulfield was influential, especially among adolescent readers. The novel remains widely read and controversial. The catcher in the rye, vividly shows us an imagine of a teenage aft
磁悬浮轴承与传统的滚珠轴承、滑动轴承以及油膜轴承相比,磁轴承不存在机械接触,转子可以运行到很高的转速,具有机械磨损小、能耗低、噪声小、寿命长、无需润滑、无油污染等优点,它是利用磁力作用将转子悬浮于空中,使转子与定子之间没有机械接触。其原理是磁感应线与磁浮线成垂直,轴芯与磁浮线是平行的,所以转子的重量就固定在运转的轨道上,利用几乎是无负载的轴芯往反磁浮线方向顶撑,形成整个转子悬空,在固定运转轨道上。特别适用于高速、真空、超净等特殊环境中。 目前已有十几家电磁悬浮轴承的新公司诞生,几十家已有的公司在生产与电磁悬浮轴承有关的产品,并且有公司开始将产品向中国市场。 有理由相信,未来磁浮轴承在数量上和型号上的应用将不断增长,因为机械运转的速度、负荷、温度、无油
1.引言 随着时代的进步和发展,单片机技术已经普及到我们生活,工作,科研,各个领域,已经成为一种比较成熟的技术,单片机具有体积小、功耗低、控制功能强、扩展灵活、微型化和使用方便等优点,广泛应用于仪器仪表中,结合不同种类的传感器,可实现诸如电压、湿度、温度、速度、硬度、压力等的物理量的测量。本文将介绍一种基于单片机控制理论及其应用系统设计的数字温度计。 本文主要介绍了一个基于AT89C51单片机的测温系统,详细描述了利用数字温度传感器DS18B20开发测温系统的过程,重点对传感器在单片机喜爱的硬件连接,软件编程以及各模块系统流程进行了详尽分析,对各部分的电路也进行一一介绍,该系统可以方便的是实现温度采集和显示,并可以根据需要任意设定上下限报警温度,它使用起来方便,具有精度高、量程
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