查询词典 pumping-back method

The paper attempts to design and development a new type of hydraulic pump. It is the design of combining the advantages of sucker rod pump and rodless botttom hole pump, without pumping rod,and depends on the hydraulic system on the ground providing the impetus. The paper uses the pump Swabbing Principle to design the main parts of the pump structure and size, analyses and calculates the up down stroke of the piston and the switching process of pump valve, uses the finite element method to analyse the main force summing element and check intensity, and designs a ground hydraulic control system to match it. Considering the need of deep mining, salvage equipment is designed. The design shows that there is feasible and reliable to realize the exploitation underground using the new hydraulic pump. The design idea in this paper enlightens the rodless botttom hole pump production in the future and other similar issues.

本文尝试一种新型液力泵的设计和开发，它的设计思想是结合有杆泵和无杆泵各自的优点，取消抽油杆，依靠地面液压系统提供动力，本文从抽油泵抽汲原理出发，设计了抽油泵主要部件的结构和尺寸，对上下冲程柱塞的运动规律和泵阀启闭过程进行分析和计算，使用有限元法对主要零件进行了受力分析和强度校核，并设计与之配套使用的地面液压控制系统，考虑深井开采的需要，一并设计了打捞装置，为理论上实现了这种新型液力抽油泵井下开采的可行性和可靠性做了一些基础的工作，本文的设计思路对今后无杆泵采油等类似问题的研究做了有益的尝试。

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。

BP has meanwhile said another method is to be tried to stop the oil leak, the pumping of mud into the blown-out wellhead.

同时，BP 承诺将尝试使用另外一种方法来阻止漏油，向源头处注入泥浆来阻止石油继续泄漏。

The method was applied to measure the hydraulic losses of inlet and outlet conduit of bulb tubular pump system of the pumping station respectively.

采用本文的方法对某泵站前置灯泡和后置灯泡贯流泵的进、出水流道分别进行了模型试验，测试了流道水力损失。

The method was applied to measure the hydraulic losses of inlet and outlet conduit of bulb tubular pump system of the pumping station re.

采用本文的方法对某泵站前置灯泡和后置灯泡贯流泵的进、出水流道分别进行了模型试验，测试了流道水力损失。

This paper recommends a method of measuring flow by the flute pipe-pressure difference gauge, which is suited to measure flow at pumping station.

本文推荐一种适合泵站单泵测流的笛形管——差压计测流方法。

Based on the theoretical model coupling Maxwells equation with the rate equation of 4 level inverted population, the numerical simulation is made via the FDTD method and MATLAB programs. The simulation results show that 1. With the increase of the pumping rate, both the localization of the electric field and the spectrum mode numbers will change; 2. The lasing threshold decreases by increasing the size or concentration of the scatters; 3. The lasing threshold also decreases by increasing the size of samples or strengthening the sample randomness.

在理论和实验研究的基础上，利用麦克斯韦方程与四能级反转粒子数的速率方程相耦合的理论模型，采用时域有限差分方法和MATLAB程序对随机激光泵浦阈值特性进行了数值模拟与计算，模拟结果显示：随着泵浦速率的增大，出现了阈值前后电场强度局域态及频谱模式数的改变；随着散射体粒径的增大，浓度的增大，阈值呈现下降的趋势；随着样品长度的增大，随机强度的增强，阈值也呈现下降的趋势。

It introduces the renovation method for cutter suction dredger by add ing hydraulic arm－ type mud pump＆ suction device as main part of mud suction＆ water jetting device, through which the original cutter suction dredger is renovated into a compatible dredging workboat with the functions of both cutter suction and pumping.

介绍加装液压机臂式吹吸装置作为吸泥、冲水装置主体的改造办法，将原绞吸式挖泥船改造成集绞吸和吹泥一体的兼容型疏浚工程船。

Simulation results show that the load control method with variable event timing can effectively decrease the pumping loss at engine partial load condition up to 57%, and the brake specific fuel consumption is improved to 5.63%.

结果表明，采用可变气门开启持续期负荷控制方式可以有效降低汽油机部分负荷泵气损失，最大降低幅度达到57%，同时比油耗降低了5.63%。

Based on the analysis of the process of regenerative braking,this paper put forward a new method to restrain the pumping voltage by changing PWM ratio.

文中通过对再生制动过程的分析，提出了通过控制占空比的办法来抑制泵升电压。

For the head-teacher of the class said that I had seriously broken the school rules,which led me to a three-day suspend class.

为什么呢？因为我的班主任说我严重的违反了校规，于是让我停课三天。

Many of them believe that the conversion of thousands of working-class folk in England spared that nation from the mass carnage and the tyranny that came with the revolution in France.

他们之中有许多人相信，在英国数以千计的劳工阶级之悔改信主使英国免於遭受如法国大革命所造成的大屠杀和专制暴政。