科技

Lin Lin always, each have its to use the indication science and technology with photograph correspondence, the application with large size TV, at present the commonnest is a back umbriferous, PDP, plant with LCD3 indication science and technology.

各色各样，各有其应用与相对应的显示科技，以大尺寸TV的应用而言，今朝最常见的就是背投影、PDP、与LCD三种显示科技。

At the same time,because people regard technology as an example of democrtic pattern,they mixed technology into Human Nature unconscientiously and made the intention of Human Nature more colorful,more suitable for the modern society.

同时，由于人把科技作为民主格局之一员，也就自觉不自觉地把科技融入到自己的人性之中，使自身的人性内涵更丰富，更适应于现代社会。

With the support of a major research grant of Zhejiang Province (No. 001101027) and the Plan of Promoting Education of Excellence of Zhejiang University in the 21st Century, this dissertation is devoted to address the above problems and fabricate an L-band EDFA with low cost, high performance and technological innovation.First the mechanism of an erbium doped fiber amplifier is introduced. Various theoretical models based on classical rate propagation equations are summarized and compared for their applications. We use a modified numerical model based on the Giles model, which agrees with the experimental results well. This serves as the theoretical base for the whole thesis and will be used to optimize the characteristics of EDFAs. A novel method based on a map of noise figure and gain is proposed to analyze efficiently the dependence of the noise figure and gain for EDFAs on the EDF length and the pump power. The characteristics of various EDFAs are studied and compared.Secondly, some important parameters are introduced to describe the characteristics of EDFAs. The methods and the experimental setups for measuring the gain and noise figure of an EDFA are emphasized. We introduce how to measure the characteristics of each component of an EDFA, especially the gain and absorption coefficient of an erbium doped fiber.Thirdly, four types of simple and novel L-band EDFA structures with low noise, high gain and low gain ripple are proposed to satisfy the requirement of a DWDM system. They can be classified into two categories. In the first category, a single ASE pumping is served asa secondary pump. This category includes the following three types. Type: a new construction using a fiber Bragg grating in an unpumped EDF section at the input side. Type: a new structure of L-Band EDFA with two-stage pumps, which utilizes the forward ASE as a second pump.

本论文本着科技创新、服务于生产实践的精神，以设计价格低廉，性能优越、结构合理简单的L-band EDFA为目标，依托浙江省科技厅重大科学基金资助项目(001101027)和浙江大学振兴教育计划资助的全光网络的搭建—《光通信技术》课程实验建设项目，展开了如下工作：首先，介绍了掺铒光纤放大器的工作原理，归纳总结了基于速率方程基础的EDFA的各种理论模型，分析比较了各个模型的特点和适用场合，最终选择完善的Giles理论模型作为本论文分析设计EDFA的理论基础；针对实际实验条件提出了修正的EDFA模型的数值计算方法；创新地提出了增益—噪声系数全局分析法，直观有效地分析了EDFA的增益和噪声系数与掺铒光纤长度和泵浦功率的依赖关系，并对各种EDFA的性能作了全面的比较；第二，介绍了掺铒光纤放大器特性参数的定义与测量方法，重点介绍了噪声系数和增益系数的测量方法及实验装置；介绍了组成掺铒光纤放大器各组件的特性测量方法，重点介绍了测量掺铒光纤参数的方法和实验装置；第三，针对WDM系统对L-band EDFA谱平坦、低噪声、高增益的要求，我们创新地提出了四种不同的L-band EDFA结构，按设计思路可以分为两大类：一类是基于单抽运二级泵浦法，这一类包括在未泵浦掺铒光纤的输入端插入一根布拉格光纤光栅的两段L-band的EDFA的新结构；基于前向ASE光作为二级泵浦源推动下一级EDF工作的泵浦分配、两段级联L-band的EDFA的新结构；基于单根光纤光栅、泵浦分配、两段级联的EDFA；另一类则是基于同时应用前后向C-band ASE作二级泵浦源的双抽运法，如基于前后向ASE光作为二级泵浦源的三段级联L-band的EDFA的新结构。

However,regional differences,imbalanced government policies,unstandardized market regulations have resulted in imbalanced development among different regions,disqualification of the service staff,low service quality,and the great survival pressure for the third category of service agencies.

但是，由于地区差异较大、政府政策失衡、市场规范不健全等因素，我国科技中介服务存在地区发展不平衡、第三类科技中介服务机构面临生存压力较大、服务人员素质不高、服务质量低等问题。

Commending CR's as well as Tangshan Company's breakthrough in high-speed train development as well as the spirit of unyieldingness and determination, Wan Gang encouraged the Tangshan people to exploit the joint action plan by MOST and MOR as well as the National 11th FYP on Scientific and Technological Support, keep building innovation capabilities, step up hi-tech application and promotion and build even more advanced EMUs so as to make greater contribution to railway's equipment modernization.

万钢对铁路部门和唐车公司迎难而上、勇于登攀，取得高速动车组研制技术的重大突破表示赞赏，并勉励唐车公司广大科技人员和全体干部职工，要依托科技部与铁道部签署的两部联合行动计划和国家&十一五&科技支撑计划，不断提高企业自主创新能力，加快高新技术成果的转化和推广应用，制造出更加先进的高速动车组，为铁路技术装备现代化作出新的更大贡献。

Therefore, we Chinese should turn ourselves to upbring a large troop which makes up with many technology innovatiors, we should change the ways of economic growth and keep the proper economic growth, we should import advanced te...

为此，中国应该致力于培养一支宏大的创新型科技人才队伍，转变经济增长方式，保持经济的较高增长，积极引进国外最新技术，争取在一个不太长的时期内跻身于世界科技强国之列。

Its Welf Schnell who advocated to establish the Study Group for the History and the Philosophy of Chinese Science and Technology, Iwo Amelung who did some researchs on the hitory of Chinese water conservancy, the graphics and the physics, Dieter Kuhn whogot outstanding accomplishments in research on the history of Chinese fabric and Song Dynasty, Hans Ulrich Vogel who published lots of papers mainly related to the salt history in China, and attached himself to many activities sponsored by some academic organization, Paul U.

维快倡导建立了中国科技历史科技哲学中心；阿梅龙对中国水利史、中国制图学、物理学等方面的问题都有所研究；迪特库恩在中国纺织史、宋史的研究方面成果卓著，并且著述宏丰；傅汉思以盐史为主的中国科技史研究发表了的大量文章，并参与为数众多的学术组织的活动；文树德Paul U。

WRAN is one of the major commercial applications of Cognitive Radio, chosen by MIT's Technology Review in May 2005 as one of the 10 emerging technologies that will transform the world.

无线区域网为认知无线电的一个主要商业应用。於2005年5月，麻省理工学院的《科技评论》把认知无线电，列为「改变世界的十项新兴科技」之一。

We aim at " people oriented , technical innovation ", a series of high technology digital voting conference system , wireless voting system , IC sign in system , video tracking system , simultaneous interpretation conference system sell to the market at a dash .

本着&以人为本，科技创新&。一系列高科技的数字表决会议系统、无线表决系统、IC卡签到系统、视像跟踪系统、同声传译会议系统一气呵成推出市场。

Many are opposed to a technocracy because they do not wish to be ruled by technical experts.

很多人反对科技专家政治，因为他们不想被科技专家控制。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。