工作条件

The Kalina cycle which uses ammonia-water mixture as the working-medium, has the characteristics of lower vaporization temperature and non-isothermal heat absorption. Therefore, the Kalina cycle is used in low temperature waste heat recovery based on introduction of operating principle. The primary parameters of Kalina and Rankine cycle are optimized by mean of genetic algorithm respectively, and the net output power of the two cycles is compared on the same condition.

卡林纳循环采用氨水混合物作为工质，具有气化温度低和非等温吸热的特点，因此，在简要介绍其工作原理的基础上将其应用于中低温余热回收，采用遗传算法对卡林纳循环和常规朗肯循环的主要参数进行了优化，在相同的余热条件下，比较了卡林纳循环和常规朗肯循环的净输出功率。

Many researchers have devoted their work to the development of modal analysis extraction techniques in order to obtain more reliable identification of the modal parameters. There are many damping identification methods, but each one has different merit and defect. In order to find which one is the most reliable method with respect to certain characteristics, this thesis focus on how to identify structure's damping in time domain. The following works have been done in this thesis: 1. Investigate four modal analysis methods——the LSCE Method, the Ibrahim Time Domain Method, the Time Domain Collectivity Modal Parameter Method, the Rational Fraction Polynomial Method and improve on the ITD Method in arithmetic.

本文主要做了如下工作： 1、集中研究了四种常用的模态识别方法，即最小二乘复指数法、Ibrahim时域法、时域总体模态参数辨识法及有理分式多项式法，并对ITD法在算法上进行了一定的改进； 2、建立结构动力模型，利用这四种方法在具体条件下识别结构的阻尼，并绘制相应的图； 3、讨论不同的情况下，不同的识别方法对阻尼识别精确性的影响； 4、基于业已明确的阻尼识别的精确性，根据研究的需要，指出在实际的识别过程中，如何选择最佳的识别方法以及识别过程中需要注意的问题； 5、选择最为精确的阻尼识别方法，以导师李书进教授在日本京都大学防灾研究所强震反应实验室所做的一足尺木制结构房屋的动力测试实验为实测模型，识别其阻尼； 6、在本文的最后，尽作者所知，提出了一些需要改进的地方，并对未来的研究方向给出了作者的建议。

The macroscopical countermeasures are guidig under the rules of rooting on realities, step by step, distinctively supervising and making factualistic and innovative breakthrough; harmonizing the relationships between generality and particularity, dot and plane, internality and externality, importance and unimportance, receival and innovation, reality and possibility in rural curriculum reform. The middle-scopical countermeasures are encourageing active push of the standardization of schooling condition, the integration of rural administration, the communion of teacher resources arrangement, proportioning the curriculum implementation, variety of experimental school choosing, inspiring teaching promoter and school-based studying development, and putting forward constructive policy suggestions to drive the rural curriculum reform to further development.

宏观层面要坚持一切从实际出发、循序渐进、均衡发展、重点突破、求实创新的指导原则，正确处理好农村课程改革中共性与个性、点与面、内因与外因、重点与一般、继承与创新、现实与可能等六个方面的关系，中观层面要积极推行办学条件标准化、乡村管理一体化、师资配置共享化、课程实施均衡化、实验试点多样化、工作推动激励化和学校发展校本化等七个方面适切性的管理对策，并为教育行政提出政策性建议，不断推动农村课程改革向纵深发展。

The research work presented in this dissertation focused on developing the scheme and techniques of OPCPA. This dissertation gives the results of the theoretical and experimental investigation on OPCPA scheme. The validation of OPCPA at high energy level was demonstrated successfully. And some important results were achieved. Several key techniques related to developing table-top ultra-intense and ultra-short OPCPA laser system were put forward, for example, the generation of femtosecond seeding pulses, the precisely temporal synchronization of the pump and signal pulses, the pulse stretching and recompression, the OPCPA process with high energy conversion efficiency and etc. Based on the integration of these key techniques, a 1.46-TW/153-fs OPCPA table-top ultra-intense and ultra-high laser system has been developed, which, to the best of our knowledge, has generated laser pulses with the shortest pulse duration and the highest peak power among the joule level OPCPA systems in the world.

本学位论文工作主要是瞄准 OPCPA 这一国际上提出不久并处于初级阶段的新概念，重点开展了 OPCPA 新原理的理论模拟、实验验证，以及基于 OPCPA 新原理的小型化超强超短激光系统的研究与发展，创造性地解决关键科学技术问题，建立并发展相关关键科学技术，如超短脉冲种子源的产生、小型化强激光泵浦源的研制及其脉冲的整形、信号光与泵浦光的精确同步、高效率光学参量放大及高保真脉冲展宽与压缩等关键技术，并在单元技术的总体集成方面取得了重大创新性进展与突破性研究成果，获得了国际上高量级泵浦条件下 OPCPA 激光研究中峰值输出功率最高且脉冲宽度最短的总体领先结果。

Studies on basic working principles and designs of fiber lasersThe basic working principles as well as the major characteristics of laser and fiber lasers are firstly reviewed,including the interaction between light and matter, the laser oscillation conditions and the spectrum distribution,the gain characteristic and spatial hole burning effect,the influence of external environment on the stability of laser output and the actual limits of fiber laser bandwidth;The designs of bidirectional single-mode Er-doped fiber ring laser and multi-wavelength laser is then discussed,respectively;The characteristics of dynamic grating reflection spectrum of the fiber saturable absorber is systematically analyzed.?

在激光型光纤传感器的设计、实验现象的理论解释等方面做了如下的研究工作：光纤激光器的基本原理与设计方案概述了激光和光纤激光器的基本原理，包括光与物质的相互作用，激光振荡的条件及频谱分布等激光产生的基本原理：掺铒光纤的增益性质，空间烧孔效应和外界扰动对激光输出稳定性的影响，光纤激光器的实际极限带宽等光纤激光器的相关知识；分别讨论了双向单纵模环形腔激光器和多波长激光器的设计方案；系统地分析了掺杂光纤饱和吸收体中形成的动态光栅的反射谱特性。

The appropriate assembly temperature is related to mechanics properties of material and operating temperature, so reiterative computations are necessary to find an appropriate assembly temperature by the method that makes the maximal tensile stress smallest under conditions that the maximal compressive stress is less than the compressive yield point of material.

安装温度的选择与材料的力学性能及零件的工作温度紧密相关，因此选择合适的安装温度需要反复计算，其方法是在保证循环中的最大压缩应力小于材料压缩屈服点的条件下，使最大拉应力最小。

This thesis, based on detailed analysis of a variety of issues relevant to the campus-based hi-tech enterprises, points out that the formation and development of the enterprises is a historical and circumstantial event. Emergence of the enterprises is a natural outcome of a university's diverse functionality and extension, representing its "third function".

本文主要通过对高校科技产业发展中的诸多问题进行分析，指出发展高校科技产业是我国特定历史条件下的产物，它的形成和发展有着一定的历史渊源，是高等学校职能发展的必然结果，是高校科技工作的延伸，体现着高校的"第三功能"。

He hasn't got the requisite qualifications for this job.

他不具备这项工作所必需的条件。

The residuary energy in the resonant inductance can be feedback to the power source, as well. In addition, all of the auxiliary switches in the inverter are in ZCS mode.

通过对提出电路工作原理的详细分析，给出了该电路功率开关器件零电压过渡条件，在此基础上研制了一台原理样机，验证了提出的方法的可行性。

It can make seeding, mixing and covering together and conquer the unfavorable influence to improve the speed and quality of revegetation.

喷植工法之喷植技术可使播种、混种、覆盖等工作一次完成，可以克服不利条件的影响，提升了植生绿化速度和质量。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。