Analysis and design of micro-switch based on MEMS

ＭＥＭＳ开关在结构上类似微型继电器，但具有速度快的优点。微机械开关没有使用ＰＮ结或金属结，消除了半导体开关ＰＮ结非线性问题和因扩散电阻等带来的高插入损耗问题，与传统的电子开关相比，具有隔离度电压高，可以实现开关回路与驱动回路完全隔离等优点。在自动测试、控制系统、通信系统的信号通路等领域有着广泛应用潜力，同时，ＭＥＭＳ开关是微机械技术中的一类有代表性的结构，是很多微机械器件的基础。 常见的开关结构有悬臂梁、空气桥和扭转摆三种，目前均采用静电驱动方式。前两种结构又分为串联（较低频率）和旁路（高频）两种形式。串联式悬臂梁开关类似于ＦＥＴ。有静电电压作用在梁和底面电极时，梁发生偏转，在源极和漏极之间...MEMS switches based on metal-metal contact are useful in a variety of power management information processing and communication systems because their on resistance is lower than that of semiconductor switches and their off resistance and transmission frequency are higher than that of semiconductor switches. Typically, there are three kinds of different structure of micro-switch: cantilever beam, ...学位：工学硕士院系专业：物理与机电工程学院机电工程系_测试计量技术及仪器学号：19992900

Gigabit ethorplet:review and future

以太网现在已经是最普遍的局域网技术 ,占领了 90 %以上的市场。本文对以太网的原理做了介绍 ,回顾了以太网的发展历程 ,介绍了千兆位以太网的概念及相关标准 ,同时介绍了几种千兆位以太网的实现 ,最后展望了以太网的最新方向——— 10G以太网Ether NET is the most prevalent LAN technic now,it has occupied almost 90% LAN market.This paper introduced the principle of Ethernet,reviewed te course of it,and introduce the standard of Gigabit Ether Net.At last,We prospected the new development of GbE-10G Ether Net

Deformation analysis of silicon cantilever for electrostatic microswitch

介绍了一种计算微开关的硅悬臂梁在电场力作用下的变形的方法 ,由于作用在梁上的载荷随着梁的变形而变化 ,用积分法计算存在相当困难 ,以下提出了一种计算变形的新方法 :将梁分为m个小段 ,则梁上的分布力可近似为m个集中力 ,将初始均布载荷分成n步 ,逐步加载 ,在每个载荷步后根据变形结果修正m个集中力 ,同时增加一个载荷增量 ,作为下一步的载荷。只要m和n取到充分大 ,就可得到梁变形的精确结

The Design and Fabrication Process of Double Sided Touch Mode Capacitive Pressure Sensor

双面接触式电容压力传感器除了具有单面接触式电容压力传感器的优点 ,还有它的特别之处 :双面接触式电容压力传感器被施加同样的压力时 ,可以得到比单面接触式电容压力传感器增大一倍的电容量和灵敏度 ,而且不会因此增加多少成本 ;工作时可靠性更高 ,即使一面失灵还有另一面可以正常工作。文中就双面接触式电容压力传感器的工艺进行了初步设计

Damage to mangroves from extreme cold in early 2008 in southern China

通讯作者Author for correspondence (E-mail: [email protected])2008年初,我国南方19个省经历了50年一遇的持续低温雨雪冰冻天气。极端气候对华南沿海各省的红树林区造成不同程度的危害。2008年3月,在我国南方各省红树林区的10个代表性地点,对这次寒害造成的红树植物伤害程度进行了系统的调查。结果表明:冬季低温对红树林的影响极为显著,特别是在低纬度的海南、广西和广东湛江,由于极端低温正值夜间退潮,对红树林的影响更为显著;在纬度较高的福建,本地红树种类秋茄(Kandelia obovata)、桐花树(Aegiceras corniculatum)和白骨壤(Avicennia marina)及引种的木榄(Bruguiera gymnorrhiza)等,由于长期适应于冬季较低的气温或在种植前经过抗寒锻炼,具有较强的抗寒能力。各地主要红树植物中,广布种秋茄、桐花树和白骨壤最为耐寒,其耐寒性均大于红树科的木榄、海莲(Bruguiera sexangula)和红海榄(Rhizophora stylosa)。海桑(Sonneratia caseolaris)对温度的敏感性最强,抗寒能力最低,因此,即使在其原产地海南也受到较为严重的寒害,在纬度更高的引种地出现大面积受害甚至全部死亡,而从孟加拉国引种的无瓣海桑(Sonneratia apetala)却显示出一定的抗寒能力。同一地点的红树植物幼苗的抗寒能力低于大树。此次寒害也造成了苗圃场的种苗大量死亡,成熟的植株提前落花落果,这势必会影响后继一两年内红树林的自然更新和人工造林。因此,在未来红树林造林或人工引种中,一定要考虑到红树植物的抗寒能力。国家自然科学基金(30671646和30700092);厦门大学“闽江学者”启动基

Internal Control,Legal Environment,and Law abiding Corporate Citizen

本文实证检验了“内部控制合理保证企业遵守适用的法律与法规“这一目标的实现效果,并考虑了法治环境的调节效应。研究表明:内部控制质量与公司违规概率及频率均显著负相关,即内部控制质量较高的企业更可能是守法的企业公民;而且,该效应在法治水平更低的地区更强,这意味着高质量的内部控制可在一定程度上弥补外在制度的不足。进一步发现,内部控制五大要素中仅内部环境要素与公司违规概率及频率显著负相关。本研究丰富了内部控制经济后果的相关研究,对监管当局和企业均具有重要的启示意义。This study has empirically studyed the result of a target in internal control,which underscores that inter nal control provides reasonable assurance on firm′s compliance on applicable laws and regulations.Results show that the quality of firm′s internal control is significantly and negatively associated with the probability and frequency of irregularity,indicating firms of high internal control quality are more likely to be law abiding Corporate Citizens.Further,this effect is more pronounced for firms located in provinces or districts where the level of ruling by law is relatively lower.This implies that effective internal control can contribute to making up the deficiency of macro institutions.Additional evidence suggests that among five internal control factors,only the quality of Internal Environment is significantly and negatively related to the probability and frequency of irregularity.This paper enri ches literature on internal control and has material implications for the authorities and firms.国家自然科学基金重点项目(项目批准号:71332008);国家自然科学基金青年项目(项目批准号:71302060)的资助; 教育部人文社会科学重点研究基地重大项目(项目批准号:10JJD630003)的阶段性成

Political Connection, Accounting Information and Banks' Loan Allocation Efficiency:Empirical Evidence from Chinese Listed Companies in Private Sector

本文比较了政治关系和高质量会计信息的银行信贷资本配置效率。以2001-2009年在我国沪深两市上市的民营企业为样本,研究发现:政治关系比高质量的会计信息更有助于企业获得数额更大、期限更长的银行贷款(“融资效应“);但随银行贷款的增加,政治关系组企业的投资效率既未提高也未降低,而高质量会计信息组企业的投资效率显著提高(“投资效应“)。即政治关系组企业虽获得了更多的银行贷款,但资本利用效率更低。这说明政治关系扭曲了银行信贷资本配置,且在一定程度上“挤占“了高质量会计信息企业所需的资本,抑制了其优化资本配置功能的发挥。其启示意义在于,中国经济的持续与健康发展还是得依赖包括会计信息披露在内的正式制度的建设与完善。This study compares the banks' loan allocation efficiency of political connection with the one of high quality accounting information.Sampling from Chinese private firms listed in SZSE and SHSE during 2001 to 2009, we find political connection does be more likely to help firms get more and longer term loans from banks than accounting information of high quality(Financing Effect); in addition, with the increasing of loans from banks, the investment efficiency of politically connected firms neither improve nor deteriorate, firms of high quality accounting information, however, greatly increase their investment efficiency(Investment Effect).These mean political connected firms have acquired more loans from banks, but the utilizing efficiency does be low.Therefore, we can conclude that political connection distorts the allocation of banks' loans, it, to certain extent, extrudes capital necessary for firms with high quality accounting information, which inhibits the function of optimizing capital allocation of high quality accounting information.This finding implies that the sustainable and healthy development of Chinese economy should depend on formal institutions/mechanisms including accounting information disclosure.国家自然科学基金面上项目“企业集团的保险效应与风险承受:基于非分散化投资的民营控股股东的视角”(批准号:71272229);国家自然科学基金青年项目“集团化运营、银行贷款与资金配置效率”(批准号70902052);国家自然科学基金重点项目“信息生态环境与内部控制有效性问题研究(批准号71332008)”;国家自然科学基金青年科学基金项目“LLP转型、法律风险与审计行为研究”(批准号:71302060); 教育部人文社会科学重点研究基地重大项目“中国上市公司内部控制评价与指数研究”(批准号10JJD63

Internal Control,Integration Ability and Performance in merger and acquisition——Empirical evidence from Chinese listed firms

内部控制在合理保证财务报告可靠性方面的作用已为大量经验证据所证实,但鲜有文献实证检验内部控制在企业具体经营活动中所发挥的作用。本文围绕企业并购活动,以2008—2009年已完成交易且上市公司为收购方的并购事件为样本,进行实证检验,结果发现:收购方的内部控制质量越高,并购完成当年及其后3年内破产风险增大的幅度越小、并购业绩也越好。这说明,高质量的内部控制有助于增强企业并购后的整合能力,从而提高并购业绩。该研究丰富和拓展了与内部控制和企业并购相关的文献,对于企业并购活动与内部控制实务有一定的启示意义。The role of internal control on reasonably assuring the reliability of financial report has been verified by extensive empirical evidences,however few literatures explores the role of internal control on detail firms' operational activities.Therefore,taking merger and acquisition( M&A) activity as example,with sample of M&A events which listed firms are buyers and have been finished in 2008 and 2009,we find that buyer's internal control quality is negatively associated with increasing of bankruptcy risk in right and subsequent 3 years when M&A has been completed; consistent with this,the higher firm's internal control quality is,the better M&A performance will be.These findings indicate that higher quality internal control can improve firm's integration ability and performance after M&A.This study enriches and broadens literatures on internal control and M&A,and has certain implication for firms' internal control practice.教育部人文社会科学重点研究基地重大项目“中国上市公司内部控制评价与指数研究”(项目批准号:10JJD630003); 国家自然科学基金重点项目“信息生态环境与企业内部控制有效性问题研究”(项目批准号:71332008)的阶段性成