第一篇：论文英语1 中英文版
森林工程专业英语考核
——压力之源—泵和压缩机
原文名称：压力之源—泵和压缩机
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内容提要
从原理上讲，大多数适合于泵送流体的泵都可以泵送空气或气体，尽管大多数油泵几乎不会作为空气压缩机来用，而某些压缩机未作调整也不可以输送非压缩性流体。泵和压缩机有共同之处，亦有不同之处。
关键词：
泵压缩机流体压力
压力之源—泵和压缩机
从原理上讲，大多数适合于泵送流体的泵都可以泵送空气或气体，尽管大多数油泵几乎不会作为空气压缩机来用，而某些压缩机未作调整也不可以输送非压缩性流体。
从总的原则来考虑，一台可以提供足够大压力来实际使用的液压泵，保证其能力的主要要求是：
a.应采取控制流体泄漏的措施。应当采用特殊密封，或者减小工作间隙。b.要完全均匀而不是脉冲式地输送流体。
c.在运行过程中，流体不能存在空穴现象，因为实际使用的流体都是非压缩性的。
d.机械平衡达到足够的程度，使泵能尽可能快地旋转，以减小保证输出一定功率时的泵的体积。
e.由于泵内有内压力，要采取适当的措施，最大限度地减小工作零件或泵壳等部件变形的影响。
f.间隙量要小，以便在泵起动时能很快转动起来，对空气流体，泵就像压缩机那样，把空气通过输送管排出，而不是让它滞留在泵中。
g.配置适当的进油阀或配流装置，已便提高泵的吸油能力，在高空飞行的飞机液压装置上或使用较高粘度的液体作为液压油时，更应采取这些措施。应该注意的是入口阀或油门开启的时间，这几乎和油口尺寸一样的重要。对一台良好的压缩机的主要要求是：
a)与机械间隙相适应的尽可能小的间隙容积。
这是因为在间隙容积中被压缩的任何气体都将会再次膨胀而不是被排放掉。因此，不仅将影响泵的输出，而且影响可能产生的最高压力。
b)除了低压泵外，在两个或更多的压缩阶段之间，尽量布置中间冷却。由于气体是进行绝热式压缩的，而不是等温压缩的，因此，首先希望减少作功和功率的损失；其次，由于间隙容积的原因，会减少总体的输出损失。
c)泵中空气的预压缩压力应升高到输送管中的压力。
尽管标准往复泵因具有自动阀或受压弹簧阀能保证这点，但某些旋转式压缩机则必须配专用气阀来配流，以便获得预压缩，而另一些泵则全然不可能做到。泵内无预压力，一旦排气阀口打开，管道中的气体会膨胀而回到泵内，整个泵内的流体会再次被压缩。具有预压缩装置的旋转压缩机不可能输送液体油。
d)缸体的气冷或水冷措施，使得压缩机中气体温度尽可能保持等温状态，而被输送的气体体积相应增加。这是液压泵在正常情况下所不需要的特性。
e)在压缩过程中，控制气体泄漏的措施，是靠往复运动式压缩机的活塞上的密封环，或靠旋转式压缩机上的微小间隙。
f)配置足够的进气阀面积，以防止进来的气体在节流过程中所产生的容积效率损失。
各种主要类型的泵和压缩机，都采用了活塞、互相啮合的齿轮或旋转的叶轮，这些类型的泵和压缩机已经证明能够提供高压和良好性能。其他类型的泵，例如离心泵或者涡轮压缩机，是不用于压力系统的，因为它们不能产生足够高的有用的压力。
Sources of Pressure-Pumps and Compressors
Fundamentally most pumps suitable for pumping hydraulic fluid will operate
with air or gas, although most oil pumps make poor air compressors,① and some
compressors will not operate with incompressible fluid without modification.General considerations.The main requirements of a hydraulic pump capable of delivering sufficiently great a pressure to be of practical use, are:
a.Means for controlling fluid leakage either by special seals or close working clearances.b.A substantially uniform, non-pulsating delivery.c.The absence of trapping of fluid during rotation, since the fluid is for all practical purpose incompressible.d.Mechanical balance to a sufficient degree to enable the pump to be run as fast as possible, to reduce bulk for a given output.e.Adequate provision for minimizing the effect of distortion of the working parts,casings, ect.,due to the internal pressure in the pump.②
f.Low clearance volumes so that the pump will act momentarily during priming, or with aerated fluid, as a compressor, to discharge the air through the delivery line,instead of leaving it trailed in the pump.③
g.Adequate inlet valve or port provision to enable the pump to create a good suction, or alternatively, as in the case of aircraft, to operate at high altitude, and with relatively thick fluids.④ It should be noted that the time of opening of the inlet valve or port is almost as important as the size of the port.The main requirements of a good compressor are:
a.the smallest possible clearance volume compatible with mechanical clearance;this is because any gas compressed in the clearance volume will expand again instead of being discharged, and will thus adversely affect not only the output of the pump, but the maximum pressure that can be achieved.b.Except on low-pressure pumps, two or more stages of compression with as much intercooling between stages as possible.This is desirable, firstly, to reduce the wastage of work and output due to the gas being compressed adiabatically instead of isothermally, and, secondly, to reduce the overall loss of output due to clearance volume.c.Pre-compression of the air in the pump up to the pressure of the delivery line.Although the normal reciprocating pump with an automatic or spring-load delivery valve will ensure this, some of the rotary compressors have to be ported⑤ specially to obtain pre-compression, and with some it is not possible at all.Without pre-compression, as soon as the delivery port opens, the gas in the delivery pipe expands back into the pump, and the whole volume has again to be compressed.A rotary compressor with pre-compression cannot be operated with hydraulic fluid.d.Provision for air or water cooling of the cylinder so that the temperature of the air in the compressor may be kept as near isothermal as possible, and the volume of air being delivered correspondingly increased.This is a feature not normally
necessary on a hydraulic pump.e.Means for controlling gas leakages during compression either by piston rings on a reciprocating piston compressor, or fine clearances on the rotary types.f.Adequate inlet valve area to prevent throttling of the incoming air, with the consequent loss of volumetric efficiency.The main types of pump and compressor use pistons, meshing gears or rotating vanes, these having been found to give good high pressure performance.Other types of pumps, such as centrifugal pumps or turbo-compressors, are not used for pressure system as they do not produce high enough pressure to be useful.
第二篇：论文中英文摘要
论文中英文摘要
作者姓名：毛建猛
论文题目：Pushover分析方法的改进研究
作者简介：毛建猛，男，1983年10月出生，2005年8月师从于中国地震局工程力学研究所谢礼立教授，于2008年8月获博士学位。
中文摘要
如何选择合适的工程结构抗震分析和设计方法一直是地震工程领域引人关注的重要问题。随着基于性态抗震设计思想的提出和发展，作为一种简化的实现性态设计分析的方法，Pushover方法引起了广大学者和工程人员的兴趣，并得到了广泛的研究。本文针对以往Pushover方法的研究中存在的缺点和不足，对Pushover方法进行了改进，主要包括对模态Pushover方法的改进、对钢筋混凝土框架结构Pushover位移反应的修正、Pushover荷载模式与结构性态指标相关性的探讨、基于模态Pushover分析方法确定结构滞回耗能计算四个方面的问题。本论文主要研究内容和成果包括以下几个方面：
1.模态Pushover分析方法的一个重要假定是，结构在强震作用下进入非线性状态时，作用于结构的Pushover荷载模式保持不变；可是众所周知，结构发生屈服后，结构的动力特性会发生改变，结构遭受的地震荷载也会发生变化，因此各阶振型采用固定不变荷载模式的模态Pushover方法存在不足。本文提出将结构的第一振型荷载模式改进为两阶段加载模式，高阶振型荷载模式保持固定不变，对结构进行改进的模态Pushover分析。
2.建议了一种计算钢筋混凝土框架结构动力弹塑性位移反应的简便方法。通过对5个不同高度的钢筋混凝土框架结构在四类场地上80条地震动作用下的动力和静力弹塑性位移反应进行统计分析，给出了结构由静力弹塑性方法得到的目标位移估计动力时程方法得到的目标位移的修正公式。结果表明：场地条件对钢筋混凝土框架结构静力弹塑性位移反应和动力时程位移反应之间的关系影响显著；对于II类和III类场地，可以直接采用结构的静力弹塑性方法计算结果替代动力时程计算结果；对于I类场地和IV类场地，须采用修正公式对结构的静力弹塑性结果进行修正。
3.通过对4个不同高度的钢筋混凝土结构，分别进行了中等硬度场地上15条地震动作用下的非线性动力时程分析和不同荷载模式下的静力弹塑性分析，求解了结构的几个重要反应指标，包括能力曲线、顶端位移角及层间位移角、以及塑性铰分布，探讨了不同荷载模式对钢筋混凝土低层和高层结构反应指标的影响程度，建议了适用于钢筋混凝土低层和高层结构的Pushover荷载模式。
4.提出基于模态Pushover分析的结构滞回耗能计算方法。首先采用模态
Pushover分析计算结构各阶模态单自由度体系的特征参数，然后计算结构各阶模态单自由度体系对应的滞回耗能，并将其进行线性组合进而确定结构的滞回耗能，并与结构通过动力时程分析计算得到的滞回耗能进行比较，从而给出一种物理概念简单、计算操作方便的确定结构滞回耗能的方法。另外，为了便于计算结构各阶模态单自由度体系的滞回耗能，本文选取了国内外四类场地土上总计320条强震记录作为地震记录数据库，在统计分析的基础上，给出了对应于不同场地土和不同烈度区的单自由度体系等强度滞回耗能设计谱。
关键词：Pushover方法；能力谱方法；模态Pushover分析；水
平荷载模式；滞回耗能
Improvements on Pushover Analysis Procedure
Mao Jianmeng
ABSTRACT
How to select the adequate procedure for seismic analysis and design of structures is an essential problem in earthquake engineering field.With the development of Performance-based Seismic Design, Pushover Analysis procedure has attracted many scientists’ and engineers’ attentions and been widely used for its conceptual simplicity and computational attractiveness.To overcome the limitation of Pushover Analysis procedure, some improvements on this procedure were performed in this paper, including the improvement on Modal Pushover Analysis, the revision of target displacement from the pushover analysis for reinforced concrete frame, the correlation of structural response parameters with different lateral load patterns, and the computation of the structural hysteretic energy based on Modal Pushover Analysis etc.The main contents of this dissertation are as follows.1.There is an important assumption that the pushover load patterns keep unchanged even after the structure yields in Modal Pushover Analysis procedure.Recognized the adoption of invariable lateral force distributions in the Modal Pushover Analysis procedure, an improved modal pushover analysis procedure is presented in this paper to estimate the seismic demands of structures, considering the redistribution of inertia forces.It is suggested that after establishing the idealized bilinear curve, a pushover analysis is once again conducted for the first mode in two phases: before and after the structure yields.For the two phases, the structural elastic natural mode and the floor displacement vector at the initial yielding point are used as the displacement shape vector, respectively.2.The approximately estimating method of displacement of reinforced concrete(RC)frame from static pushover analysis(POA)is developed with that from non-linear response history analysis(RHA).Based on the statistic analyses of the RHA and POA results for five RC frames with different height under 80 ground motions recorded at four site conditions, the revised formula of displacements from POA is presented from RHA.The results show that the site soil condition has an important effect on the relation between RHA and POA response results.And the POA results for I and IV site condition should be revised with the formula given in this study while the POA results for II and III site condition can be approximately considered as same to the RHA results.3.The RHA under 15 ground motions recorded on the medium site condition and POA with different lateral load patterns are performed for four RC structures with different height.Several important response quantities are obtained from the RHA and POA, including capacity curves, top displacement ratios and story drift ratios, and location of plastic hinges.The influence of different load patterns on the structural performance demands is discussed for the low-and the high-wise structures.And the rational load patterns for the low-and the high-wise structures are also suggested.4.A simple procedure is presented in this paper for estimating hysteretic energy demands of MDOF systems based on the modal pushover analysis(MPA).Firstly, the characteristic parameters of the modal SDOF systems of structures are computed, and the hysteretic energy is calculated for the modal SDOF systems, then the hysteretic energy demand of structures is obtained by combining these modal demands.In addition, with statistic results of nonlinear analysis of SDOF for 320 ground motions recorded at four site conditions, the equal-strength hysteretic energy design spectra are presented for different site condition and intensity regions.Key words: pushover analysis procedure, capacity spectrum method, the
modal pushover analysis, lateral load patterns, hysteretic
energy
第三篇：论文-中英文摘要
摘要
随着信息时代的到来，信息高速公路的兴起，全球信息化进入了一个新的发展时期。人们越来越认识到计算机强大的信息模块处理功能，使之成为信息产业的基础和支柱。
车辆管理系统用计算机管理机动车辆的档案，运营管理以及驾驶员信息的一种计算机应用技术的创新，在计算机还未普及之前车辆管理都是由工作人员手工抄写的方式来操作的。现在一般的车辆管理都是采用计算机作为工具的实用的计算机智能化车辆管理程序来帮助工作人员进行更有效的机动车辆管理。车辆管理系统是典型的信息管理系统(MIS)，其开发主要包括后台数据库的建立和维护以及前端应用程序的开发两个方面。对于前者要求建立起数据一致性和完整性强、数据安全性好的库。而对于后者则要求应用程序功能完备，易使用等特点。经过分析，我们使用 MICROSOFT公司的 VISUAL BASIC开发工具,利用其提供的各种面向对象的开发工具，尤其是数据窗口这一能方便而简洁操纵数据库的智能化对象，首先在短时间内建立系统应用原型，然后，对初始原型系统进行需求迭代，不断修正和改进，直到形成用户满意的可行车辆管理系统系统。
关键字: 车辆管理系统;数据库;信息管理系统;智能化
Abstract
Along with the rise, world information that coming of information ages, information superhighway entered a new development period.People more and more know the mighty information of calculator to handle the function, and make the foundation that it become information industry with pillar.Vehicle Management System Computer used motor vehicles archives management, operation and management of a driver information computer applications innovation, Management has not yet popular in the computer before the vehicles are from the staff manual transcription to operate.Now the general management of the vehicles are used as a tool for computer computer intelligent vehicle management procedures to help staff more effective management of motor vehicles.Vehicle management system is a typical management information system(MIS), including its main development background to the establishment and maintenance of the database and front-end application development two.The request for the establishment of strong data consistency and integrity, good for the security of the data.For the latter request applications functions, such as easy to use features.After analysis, we use Microsoft visual basic development tool companies, the use of its various object-oriented development tools, especially data that can be easily accessible and concise window manipulation database intelligent objects, the first prototype application system in a short time and then, computation of the initial prototype system needs to constantly revise and improve until the formation of a viable system of user satisfaction.keywords :Vehicle management system;database;information management system;intelligentize
第四篇：论文中英文摘要格式
附件6
校优博、优硕学位论文中英文摘要格式 作者姓名：张三（宋体 四号）
论文题目：xxxxxxxxxxxx的研究（宋体 四号）
作者简介：：张三，男，xxxx年xx月出生，xxxx年xx月师从于xx大学xxx教授，于xxxx年xx月获博士学位。
中文摘要
在XXXXXXXXX技术中，具有较强XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.其研制和开发有了长足的进展。„„„„„„„
（正文：宋体 小四，博士约三千字，硕士约2千字）
关键词：（宋体 四号）
Study on the …(英文题目 字号：“Times New Roman” 三号)
Zhang San(姓名拼音 字号：“Times New Roman” 四号)
ABSTRACT
The only high temperature superconductorxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx..This is sufficient for ………….…
（正文字号：“Times New Roman” 小四，约三千字）
Key borad:(字号：“Times New Roman” 四号)
第五篇：中英文英语演讲稿-
Oil man , Chinese dream
“Now, everybody was discussing the Chinese dream, I think, realizing the great rejuvenation of the Chinese nation, is the greatest dream of the Chinese nation since the modern time.President Xi also said:We are closer than in any other time of history to the goal of rejuvenating the Chinese nation.We are more confident and capable of achieving this goal than in any other period of history".Being an oil man,I always ask myself what can I do for our great Chinese dream ?As we all know that the wiser the youths are ,the wiser the nation will be；the stronger the youths are ,the stronger the nation will be.As a new generation of oil science research,every one here shouldering the great historical mission of making china powerful and strong.You may say that this may exaggerate our role, but I want to say you are wrong.If I am a little screw ,our great dream may be a multifunction and complex machine.Through this example I just want to say I am very tiny but I am indispensable.to build CNPC into a major integrated international energy corporation’s goal has been established, which is encouraging and challenging millions of oil workers.It is a significant noble mission to achieve this goal—also the greatest dream of all the oilman, and our future is bright.At the same time, we must fully recognize that when facing the new historical opportunities,hopes, opportunities and challenges coexist, we must be prepared, pragmatic and expansive.Using the strength of development and science to create and to meet a more brilliant future of China Petroleum.Having a dream is bracing ,however, the toughest part is that we often have no ideas how to translate these dreams into actions.Well, just start with concrete objectives and stick to it.Don’t let the nameless fear confuse the eye and confound our strong belief of future.Through our talents, through our wits, through our endurance and through our creativity, we will make it.I believe that as long as all of our staff unite together and work hard ,perform our own functions and responsibilities.we must be able to achieve our great dream meanwhile enrich ourselves unwittingly!Let us unite together to make our company anintegrated international energy company and realize Chinese nation's great rejuvenation to struggle!
石油人-中国梦
当前，全中国都在谈论“中国梦”，我认为，实现中华民族的伟大复兴是当代中国人一直追求的梦想。习主席说：“当前，我们比历史任何时刻都更接近这一梦想，我们也比历史任何时刻都更有信心，更有能力去实现中华民族的伟大复兴”。
作为一名石油人，我时常问我自己，我可以为我们伟大的中国梦做些什么？众所周知：少年智则国智，少年富则国富，少年强则国强！作为新一代石油科研人员，在座的每位青年都肩负着实现中国繁荣富强的使命。你可能会说这也许夸大了我们的作用，但是我想说，你错了。如果我是一颗小小的螺丝钉，那我们的中国梦就是一个复杂而又多功能的机器。通过这个例子我想说：个人虽然渺小，但是我也是必不可少的。
建设综合性一流国际能源公司的奋斗目标是我们中国石油的宏伟目标，这是对百万石油员工的鼓舞和激励。实现这一奋斗目标就是我们中石油人的宏伟梦想，这一梦想意义重大、使命崇高、前途美好。同时，我们也必须充分认识到，在新的历史机遇面前，希望和考验同在，机遇和挑战共存，必须居安思危、求真务实、开拓进取，以发展的实力、科学的伟力，开创和迎接中国石油更加灿烂的未来。
拥有梦想是美好的，但是，如何付诸实际行动，实现梦想是困难的。需要我们从点滴小事一步步的坚持做下去，不要让无名的疑惑与恐惧影响我们对美好未来的坚定信念，发挥我们的才干、智慧与创造力，通过我们不竭的努力，我们必定实现我们的石油梦，中国梦。
我相信只要我们每个石油人团结起来并且做好我们的本职工作，我们一定能够实现我们的中国梦，在此期间我们也会不知不觉地丰富了我们自己。让我们携起手团结一致为把中石油建设成世界一流综合性能源公司，进而实现中华民族的伟大复兴而奋斗！
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