高速铁路弓网电弧电磁干扰论文中英文资料对照外文翻译文献

高速铁路弓网电弧电磁干扰论文中英文资料对照外文翻译文献
高速铁路弓网电弧电磁干扰论文中英文资料对照外文翻译文献

高速铁路弓网电弧电磁干扰论文

中英文资料外文翻译

附录A(原文)

A Simulation of Arc Generation at AC-DC Neutral Section of Electric Railway

Youngsoo Han, Kyuhyoung Choi

Abstract--This paper provides an experimental and theoretical analysis of the arc discharges generated between contact wire and pantograph of high speed railway.

A video-based arc detection device is installed on the KTX train, and arc discharges are measured for a 45.87km track section of high speed railway in Korea. It is measured that the rate of contact loss is 0.3% which is lower than the regulated value of 1.0% for high speed train, and arc discharges induced by 21 small size contact losses and 6 medium size contact losses occur continuously along the track. The power of arc discharge between contact wire and pantograph is calculated as 9.0~22.5[kW] which is approximately one-hundredth of that of the arc discharges generated at the neutral section of contact wire. The results of the measurement and the analysis suppose that a study be followed to suppress arc discharges and contact wire damages for the safe operation of high speed railway.

Index Terms—Electric railway;arc discharge;contact loss;contact wire; pantograph;neutral section.

I.NOMENCLATURE

S/S : Sub-Station of Electric Railway

SP : Sectioning Post

SSP : Sub- Sectioning Post

AT : Auto-Transformer

TF : Trolley Feeder

AF : Auto- Transformer Feeder

FPW : Fault Protective Wire

NW : Neutral Wire

NS : Neutral Section

CCTV: Closed Circuit Television

EMI: Electromagnetic Interference

LAN: Local Area Network

MCB: Main Circuit Breaker

KTX: Korea Train Express

II.INTRODUCTION

Catenary systems play a important role in supplying electric power without interruption to trains moving fast. The pantographs installed on train collect currents for traction while keeping in contact with the catenary system. Arc discharges occur between the contact wire and the pantographs, when the pantographs happen to lose contact with the contact wire.Arc discharge also occurs when the train passes through the AC-DC neutral section of the catenary system where electricity is not supplied. These arc discharges give rise to many problems such as spoiling the contact wire and the pantographs,and inducing EMI phenomena,audible noises and other environmental pollutions.Arc discharges generally have large heating power which may spoil the slider of pantograph made of sintered alloy and even breaks the contact wires.V oltage surges induced by arc discharges may produce EMI problems to the small size environment or mal-operation of electronic devices on the train. The damages caused by arc discharge will be more critical for high speed railway.The faster train moves,the more difficult to keeping in contact with catenary for pantograph. Moreover, as train speeds up, the train traction currents should be increased,which inevitably give rise to larger arc discharges.This paper provides an experimental and theoretical analysis of the arc discharges generated between the contact wire and the pantograph of high speed railway. A designated arc detection device is installed on the KTX train, and arc discharges are measured for a 45.87[km] track section of high speed railway.Arc generation frequency, arc current and arc size is measured along the track.A data analysis and an arc power model is suggested too.

III. ARC DISCHARGES BETWEEN CONTACT WIRE AND

PANTOGRAPH

The power supply system of electric railway consists of S/S and catenary system.S/S converts three phase 154[kV] electric power to single phase 25[kV] being suitable for supplying to train.High speed railway adopts AT feeding system which can supply large electric power for long distance as shown in Fig. 1. The S/S supplies AC 50[kV] to AT, and AT supply AC 25[kV] to train. The converted electric power is supplied to train by way of the catenary system which is composed of a contact wire,a messenger wire and hangers.The main purpose of the catenary system is to supply electric power without interruption to trains moving fast.The pantographs installed on train collect electric power while contacting the contact

wire of the catenary system.

Fig. 2. Shows the configuration of the catenary system. The pantograph is connected to the contact wire by its lift force against the contact wire. Contact wires supported by hangers and supporting structures has uneven stiffness points which give rise to contact losses.Moreover,as train speed up,contact loss happens more frequently.Arc discharges occur between the contact wire and the pantographs, when the pantographs happen to lose contact with the contact wire.

The contact loss phenomena are classified into three groups according to their duration; small size, medium size and large size. Small size contact loss is induced by delicate vibration of pantograph,and continues for several tenths of a second. Medium size contact losses occur when trains pass through the uneven stiff point of the contact wire, and continues for a second and below. Large size contact losses, continuing for several seconds,are induced by jumping movements of pantograph after passing through bracket supporting points of contact wire.

Contact wires have several neutral sections insulated from other parts of contact wires,in other words dead sections,which divide the sections having different phases and different supply voltages such as AC 25,000[V] or DC 1,500[V]. Trains should go into the neutral sections after making notch-off operation which

breaks the train current by MCB, otherwise the train current is interrupted by the neutral section which result in a large arc discharge between the contact wire and the pantograph as shown in Fig. 2.This arc discharge also happens when train go into the voltage-supplied section from the neutral section.

IV.MEASUREMENT OF CONTACT LOSS BETWEEN CONTACT

WIRE AND PANTOGRAPH

A.Measurement device

Fig. 4. Shows the system block diagram of arc measurement device.The device, installed on the KTX train moving at the speed of 300[km/h],measures contact force between contact wire and pantograph,vibration acceleration of pantograph, and the shape of arc discharge.Strain gauges are installed on the bow and arms of pantograph to measure the acceleration and contact force.Table 1 shows the specifications of the sensors.The image of arc discharge is captured by CCTV camera activated by arc detection sensor.Fig. 5 shows a captured image of arc discharge. All the data measured by on-board device are transmitted to wayside server via wireless LAN.

B.Measurement data analysis

The measurement has been carried out at the 45.78[km] track section of high speed railway with 300[km/h] train operation. Table 2 shows the results of the measurement; time, location of arc discharge,arc strength,the length of contact loss, train speed,arc current,and pantograph voltage.Fig. 6 show a train speed profile with voltage and current distributions.While KTX train moves on the 45.78[km] track section, 21 small size contact losses and 6 medium size contact losses are observed and https://www.360docs.net/doc/cd9182249.html,rge size contact loss was not detected at the experiment. The rate of contact loss is defined as;

rate of contact loss = sum of contact loss time ×100[%] (1)

total operation time

Korean railroad corporation suggests the rate of contact loss for high speed railway should be lower than 1.0[%]. Based on the measured data in Table 2,the rate of contact loss is calculated as 0.31[%], which means the catenary system and the pantograph of KTX fulfill the regulation in Korea. Nevertheless, it should be noted that some arc discharges are occurring continuously during the high speed operation of KTX.

C. Modeling of arc discharge

The instantaneous power of arc discharge is described by arc voltage va , and arc current i as follows,

i v p a ?= (2) The average power of arc discharge can be calculated by integrating over the period T.

????=??=T a T idt v T pdt T P 0

011 (3) It is reported that the voltage and current of arc discharge at AC circuit have the waveforms shown in Fig.7[8].The arc voltage has constant value V during half the period, depicted by square wave. Thus, the equation(3) for average power of arc discharge can be simplified by setting va = Va .

The current wave form of AC arc discharge in Fig. 7 is approximately sinusoidal having some harmonic.Neglecting the harmonics which is evaluated as several hundredths of fundamental wave, arc current can be approximated as

t I i ωsin 2= (5) Consequently, the average power is

I V tdt I T V P a T

a 9.0sin 210=?=?ω (6)

Where I is effective value of AC current, and V is arc voltage that can be measured by voltmeter.

The arc discharge between contact wire and pantograph has the following

characteristics. Arc currents are very large up to 500[A].Arc discharge between contact wire and pantograph can be simulated by arc discharge between bar and plate. Fig.8 shows a typical voltage-current characteristics of high current arc discharge between bar and plate. As the arc current is 500[A] in Table 2, arc voltage can be estimated as 20~50[V] according to displacement between contact wire and pantograph from Fig. 8. Thus, the power of arc discharge between contact wire and pantograph is calculated to be 9.0~22.5[kV A] by equation (6). The power of arc discharge between contact wire and pantograph is approximately one-hundredth of that of the arc discharges generated at the neutral section of contact wire.

V. CONCLUSION

Arc discharges between the contact wire and pantograph have been measured on the KTX train along 45.87km track using a video-based arc detection device. Although the rate of contact loss is measured as 0.3% which is lower than the regulated value of 1.0%,arc discharges occurs continuously along the track induced by 21 small size contact losses and 6 medium size contact losses.

The power of arc discharge between contact wire and pantograph is calculated as 9.0~22.5[kW] which is approximately one-hundredth of that of the arc discharges generated at the neutral section of contact wire.The results reveal that the study be followed to suppress arc discharges and contact wire damages for the safe operation of high speed train.

附录A(译文)

电力机车交-直分相装置上产生电弧的仿真实验

Youngsoo Han, Kyuhyoung Choi

摘要---本文提供了一个实验和理论分析了高速铁路中接触网和受电弓之间产生的电弧放电现象。一个基于视频的电弧侦探装置安装在韩国高速列车上,并且在韩国高速轨道上对电弧放电现象跟踪测量了45.87km线路区段。这次测量的接触损失率是0.3%,低于高速列车规定的数值1.0%,沿着轨迹不间断的发生了21小型接点损失和6个中型接点损失引发电弧放电现象。电弧在接触网和受电弓之间释放电能的估算值为9.0~22.5[kW],接近于接触网分相装置上电弧放电产生的百分之一。测算和分析的结果推想出一个研究来抑制电弧放电和接触线的损坏达到高速铁路安全运行的目的。

索引词—电气化铁路,电弧放电,接触损失,接触线,受电弓,接触网。

专业术语

S/S : Sub-Station of Electric Railway电气化铁路子站(电气化铁路供电所)

SP : Sectioning Post分区所

SSP : Sub- Sectioning Post开闭所

AT : Auto-Transformer 自耦变压器

TF : Trolley Feeder 电力机车馈线

AF : Auto- Transformer Feeder自耦变压器馈线

FPW : Fault Protective Wire 故障保护电线

NW : Neutral Wire 中性线

NS : Neutral Section 分相装置

CCTV: Closed Circuit Television 闭路电视

EMI: Electromagnetic Interference 电磁干扰

LAN: Local Area Network 局域网

MCB: Main Circuit Breaker 主断路器

KTX: Korea Train Express 韩国高速铁道

II.前言

接触网系统在给高速列车无间断提供电能上具有非常重要的作用。安装在列车上的受电弓保持与接触网系统接触以收集电流提供牵引力。电弧放电现象

发生在接触线和受电弓之间,当受电弓和接触线发生接触损失的时候。电弧放电现象也发生在列车通过接触网系统中交直分相装置当电能没有提供的情况。这些电弧放电现象会产生许多问题,例如损坏接触线和受电弓,引发电磁干扰现象,可听见的噪声和其他环境破坏。电弧放电现象通常加热功率大,会损坏受电弓上面用烧结合金制造的滑动器,甚至破坏会接触线。由电弧放电现象引发的冲击性电压可能会产生小范围的电磁干扰问题或者是引发列车上电气设备的错误操作。由电弧放电现象引发的危害对于高速铁路运行至关重要。列车运行的速度越快,保证接触网和受电弓接触就越难。此外,随着列车速度的上升,列车的牵引电流就需要增加,这无可避免的增加了电弧放电现象。本文提供了一个实验和理论分析了高速铁路中接触网和受电弓之间产生的电弧放电现象。一个基于视频的电弧侦探装置安装在韩国高速列车上,并且在韩国高速轨道上对电弧放电现象跟踪测量了45.87km线路区段。电弧产生的频率,电弧电流和电弧大小沿着行车路线被测量记录。一种数据分析和弧幂函数模型被建议引用。

III. 接触线和受电弓之间的电弧放电现象

电气化铁路的供电系统由电气化铁路子站和接触网系统组成。电气化铁路变电所把154kv的三相电力转换成25kv的单相电力,这更适合电力机车的供电。高速电气化铁路采用了自动给及系统,它能够长距离给电力机车提供强大的电能如图1。电气化铁路变电所提供50kv的交流电能给自耦变压器,自耦变压器提供25kv的交流电能给列车。转换的电能是通过接触网系统提供给列车的,接触网包括一根接触线,一根信使线和吊索。接触网系统主要的目的是无间断地给高速运行的列车提供电能。当安装在列车上面的受电弓与接触网系统中的接触线接触时收集电能。

图2展示了接触网系统的外形结构。受电弓是通过一个与接触线对抗的上升力来和接触线建立联系的。接触线通过吊索和具有参差不齐的刚力度点的支撑结构支持,这加大了接触损失的可能性。此外,随着列车速度的升高,接触损失更加频繁的发生。电弧放电现象发生在接触线和受电弓之间,当受电弓和接触线发生接触损失的时候。

接触损失现象通过它的持久性归纳为三类:小型,中型和大型。小型的接触损失是由受电弓细微的震动引发的,它的持续性只有十分之几秒。中型的接触损失发生在当列车经过接触线的刚性接点时,它的持续性只有一秒或者以下。大型的接触损失持续几秒,是受电弓通过接触线的支架而产生跳跃时刻引发的。

接触线有几个分相装置使接触线和另一接触线绝缘,另一种表达称为死区,它可以分出几个区域拥有几个不同的相和提供不同的电压,例如交流电压25000v 或者直流电压1500v。

列车应该进入分相区域如果进行了缺口操作,主断路器可以中断列车电流,否则列车电流经过分相装置时会在接触线和受电弓之间产生巨大的电弧如图2。这个电弧放电现象也会发生在列车经过分相装置中提供电压设备的时候。

IV.接触线和受电弓之间接触损失的测量

A.测量装置

图4展示了电弧测量装置的系统框图。这个测量装置,安装在运行速度为300km/h的韩国高速列车上面,测量了接触线和受电弓之间的接触力,受电弓的震动加速度和电弧的类型。变形测量器安装在受电弓弓臂上面来测量加速度和接触力。表格1展示了感测器的规格。电弧放电现象的图像是通过电弧侦探传感器的闭路电视摄像头捕捉的。图5展示了一个电弧放电现象捕捉图像。所有的数据由车上装置通过无线局域网传送给路旁的接收器。

B .测量数据分析

这个测量的数据是在运行时速为300km/h 高速列车行车路程轨迹为45.78km 上产生的。表格2展示了测量的结果:时间,电弧放电现象的位置,电弧强度,接触损失的长度,列车速度,电弧电流和受电弓电压。图6展示了高速列车电压和电流分配的配置文件。当韩国高速列车在45.78km 行车轨迹上面运行时,21小型接触损失和6个中型接触损失被观察记录下来。在整个实验中,大型接触损失没有被侦查到。

接触损失率被定义为:

接触损失率 = 总的接触损失时间 ×100[%] (1) 总的运行时间

韩国铁路公司建议高速铁路接触损失率应该低于1.0%。基于表格2的测量数据,实验接触损失率估算为0.31%,这意味着此次实验的韩国高速列车接触网系统和受电弓满足了韩国的规章制度。然而,需要注意的是一些电弧放电现象连续不断的发生在韩国高速列车运行过程中。

C .电弧放电现象模型

电弧放电现象的瞬时电功率表达为电弧电压Va ,和电弧电流I ,如下: i v p a ?= (2) 电弧放电现象平均电功率是通过一个周期T 的积分被计算出来的:

????=??=T a T idt v T pdt T P 0

011 (3) 根据调查电弧放电现象的电压和电流在交流电路中的波形如图7所示。电弧电压在半个周期有常量数值为V ,通过矩形波来描述。因此,在电弧放电现象中平均电功率的等式3里面,用va = Va 来简化。

如图7所示,交流电弧放电现象中电流波形近似看成正弦谐波。谐波估算大约是百分之几的基波值。电弧电流近似看作为:

t I i ωsin 2= (5) 从而,平均电功率为:

I V tdt I T V P a T a 9.0sin 210

=?=?ω (6) I 为交流电流的有效值,V 为电弧电压,可以通过电压表测量出来。

在接触线和受电弓之间的电弧放电现象拥有以下一些特性。电弧电流非常大可以达到500A 。在接触线和受电弓之间发生的电弧放电现象可以通过金属棒和金属板之间的电弧仿真。图8展示了金属棒和金属板之间的高电流电弧伏安特性。表格2中的电弧电流为500A ,电弧电压可以通过接触线和受电弓之间的位移估算为20~50V 。因此,在接触线和受电弓之间的电弧放电现象电功率通过等式6可以计算出来为9.0~22.5 kV A 。接触线和受电弓之间的电弧放电现象电功率近似为接触线中变相装置的电弧电功率的百分之一。

总结

利用一个基于视频的电弧侦探设备,在韩国高速轨道上对接触线和受电弓之间的电弧放电现象跟踪测量了45.87km线路区段。虽然此次测量的接触损失率为0.3%,低于规定的标准值1.0%,沿着行车轨道由21个小型接触损失和6个中型接触损失不间断地引发了电弧放电现象。

接触线和受电弓之间的电弧电功率计算值为9.0~22.5kw,近似为接触线中变相装置里产生电弧放电现象电功率值的百分之一。这个结果显示了这个研究可以用来抑制电弧放电现象和接触线的损害,保证高速列车安全稳定的运行。

毕业论文外文翻译模版

吉林化工学院理学院 毕业论文外文翻译English Title(Times New Roman ,三号) 学生学号:08810219 学生姓名:袁庚文 专业班级:信息与计算科学0802 指导教师:赵瑛 职称副教授 起止日期:2012.2.27~2012.3.14 吉林化工学院 Jilin Institute of Chemical Technology

1 外文翻译的基本内容 应选择与本课题密切相关的外文文献(学术期刊网上的),译成中文,与原文装订在一起并独立成册。在毕业答辩前,同论文一起上交。译文字数不应少于3000个汉字。 2 书写规范 2.1 外文翻译的正文格式 正文版心设置为:上边距:3.5厘米,下边距:2.5厘米,左边距:3.5厘米,右边距:2厘米,页眉:2.5厘米,页脚:2厘米。 中文部分正文选用模板中的样式所定义的“正文”,每段落首行缩进2字;或者手动设置成每段落首行缩进2字,字体:宋体,字号:小四,行距:多倍行距1.3,间距:前段、后段均为0行。 这部分工作模板中已经自动设置为缺省值。 2.2标题格式 特别注意:各级标题的具体形式可参照外文原文确定。 1.第一级标题(如:第1章绪论)选用模板中的样式所定义的“标题1”,居左;或者手动设置成字体:黑体,居左,字号:三号,1.5倍行距,段后11磅,段前为11磅。 2.第二级标题(如:1.2 摘要与关键词)选用模板中的样式所定义的“标题2”,居左;或者手动设置成字体:黑体,居左,字号:四号,1.5倍行距,段后为0,段前0.5行。 3.第三级标题(如:1.2.1 摘要)选用模板中的样式所定义的“标题3”,居左;或者手动设置成字体:黑体,居左,字号:小四,1.5倍行距,段后为0,段前0.5行。 标题和后面文字之间空一格(半角)。 3 图表及公式等的格式说明 图表、公式、参考文献等的格式详见《吉林化工学院本科学生毕业设计说明书(论文)撰写规范及标准模版》中相关的说明。

概率论毕业论文外文翻译

Statistical hypothesis testing Adriana Albu,Loredana Ungureanu Politehnica University Timisoara,adrianaa@aut.utt.ro Politehnica University Timisoara,loredanau@aut.utt.ro Abstract In this article,we present a Bayesian statistical hypothesis testing inspection, testing theory and the process Mentioned hypothesis testing in the real world and the importance of, and successful test of the Notes. Key words Bayesian hypothesis testing; Bayesian inference;Test of significance Introduction A statistical hypothesis test is a method of making decisions using data, whether from a controlled experiment or an observational study (not controlled). In statistics, a result is called statistically significant if it is unlikely to have occurred by chance alone, according to a pre-determined threshold probability, the significance level. The phrase "test of significance" was coined by Ronald Fisher: "Critical tests of this kind may be called tests of significance, and when such tests are available we may discover whether a second sample is or is not significantly different from the first."[1] Hypothesis testing is sometimes called confirmatory data analysis, in contrast to exploratory data analysis. In frequency probability,these decisions are almost always made using null-hypothesis tests. These are tests that answer the question Assuming that the null hypothesis is true, what is the probability of observing a value for the test statistic that is at [] least as extreme as the value that was actually observed?) 2 More formally, they represent answers to the question, posed before undertaking an experiment,of what outcomes of the experiment would lead to rejection of the null hypothesis for a pre-specified probability of an incorrect rejection. One use of hypothesis testing is deciding whether experimental results contain enough information to cast doubt on conventional wisdom. Statistical hypothesis testing is a key technique of frequentist statistical inference. The Bayesian approach to hypothesis testing is to base rejection of the hypothesis on the posterior probability.[3][4]Other approaches to reaching a decision based on data are available via decision theory and optimal decisions. The critical region of a hypothesis test is the set of all outcomes which cause the null hypothesis to be rejected in favor of the alternative hypothesis. The critical region is usually denoted by the letter C. One-sample tests are appropriate when a sample is being compared to the population from a hypothesis. The population characteristics are known from theory or are calculated from the population.

毕业论文英文参考文献与译文

Inventory management Inventory Control On the so-called "inventory control", many people will interpret it as a "storage management", which is actually a big distortion. The traditional narrow view, mainly for warehouse inventory control of materials for inventory, data processing, storage, distribution, etc., through the implementation of anti-corrosion, temperature and humidity control means, to make the custody of the physical inventory to maintain optimum purposes. This is just a form of inventory control, or can be defined as the physical inventory control. How, then, from a broad perspective to understand inventory control? Inventory control should be related to the company's financial and operational objectives, in particular operating cash flow by optimizing the entire demand and supply chain management processes (DSCM), a reasonable set of ERP control strategy, and supported by appropriate information processing tools, tools to achieved in ensuring the timely delivery of the premise, as far as possible to reduce inventory levels, reducing inventory and obsolescence, the risk of devaluation. In this sense, the physical inventory control to achieve financial goals is just a means to control the entire inventory or just a necessary part; from the perspective of organizational functions, physical inventory control, warehouse management is mainly the responsibility of The broad inventory control is the demand and supply chain management, and the whole company's responsibility. Why until now many people's understanding of inventory control, limited physical inventory control? The following two reasons can not be ignored: First, our enterprises do not attach importance to inventory control. Especially those who benefit relatively good business, as long as there is money on the few people to consider the problem of inventory turnover. Inventory control is simply interpreted as warehouse management, unless the time to spend money, it may have been to see the inventory problem, and see the results are often very simple procurement to buy more, or did not do warehouse departments . Second, ERP misleading. Invoicing software is simple audacity to call it ERP, companies on their so-called ERP can reduce the number of inventory, inventory control, seems to rely on their small software can get. Even as SAP, BAAN ERP world, the field of

汽车专业毕业设计外文翻译

On the vehicle sideslip angle estimation through neural networks: Numerical and experimental results. S. Melzi,E. Sabbioni Mechanical Systems and Signal Processing 25 (2011):14~28 电脑估计车辆侧滑角的数值和实验结果 S.梅尔兹,E.赛博毕宁 机械系统和信号处理2011年第25期:14~28

摘要 将稳定控制系统应用于差动制动内/外轮胎是现在对客车车辆的标准(电子稳定系统ESP、直接偏航力矩控制DYC)。这些系统假设将两个偏航率(通常是衡量板)和侧滑角作为控制变量。不幸的是后者的具体数值只有通过非常昂贵却不适合用于普通车辆的设备才可以实现直接被测量,因此只能估计其数值。几个州的观察家最终将适应参数的参考车辆模型作为开发的目的。然而侧滑角的估计还是一个悬而未决的问题。为了避免有关参考模型参数识别/适应的问题,本文提出了分层神经网络方法估算侧滑角。横向加速度、偏航角速率、速度和引导角,都可以作为普通传感器的输入值。人脑中的神经网络的设计和定义的策略构成训练集通过数值模拟与七分布式光纤传感器的车辆模型都已经获得了。在各种路面上神经网络性能和稳定已经通过处理实验数据获得和相应的车辆和提到几个处理演习(一步引导、电源、双车道变化等)得以证实。结果通常显示估计和测量的侧滑角之间有良好的一致性。 1 介绍 稳定控制系统可以防止车辆的旋转和漂移。实际上,在轮胎和道路之间的物理极限的附着力下驾驶汽车是一个极其困难的任务。通常大部分司机不能处理这种情况和失去控制的车辆。最近,为了提高车辆安全,稳定控制系统(ESP[1,2]; DYC[3,4])介绍了通过将差动制动/驱动扭矩应用到内/外轮胎来试图控制偏航力矩的方法。 横摆力矩控制系统(DYC)是基于偏航角速率反馈进行控制的。在这种情况下,控制系统使车辆处于由司机转向输入和车辆速度控制的期望的偏航率[3,4]。然而为了确保稳定,防止特别是在低摩擦路面上的车辆侧滑角变得太大是必要的[1,2]。事实上由于非线性回旋力和轮胎滑移角之间的关系,转向角的变化几乎不改变偏航力矩。因此两个偏航率和侧滑角的实现需要一个有效的稳定控制系统[1,2]。不幸的是,能直接测量的侧滑角只能用特殊设备(光学传感器或GPS惯性传感器的组合),现在这种设备非常昂贵,不适合在普通汽车上实现。因此, 必须在实时测量的基础上进行侧滑角估计,具体是测量横向/纵向加速度、角速度、引导角度和车轮角速度来估计车辆速度。 在主要是基于状态观测器/卡尔曼滤波器(5、6)的文学资料里, 提出了几个侧滑角估计策略。因为国家观察员都基于一个参考车辆模型,他们只有准确已知模型参数的情况下,才可以提供一个令人满意的估计。根据这种观点,轮胎特性尤其关键取决于附着条件、温度、磨损等特点。 轮胎转弯刚度的提出就是为了克服这些困难,适应观察员能够提供一个同步估计的侧滑角和附着条件[7,8]。这种方法的弊端是一个更复杂的布局的估计量导致需要很高的计算工作量。 另一种方法可由代表神经网络由于其承受能力模型非线性系统,这样不需要一个参

毕业论文 外文翻译#(精选.)

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英语专业毕业论文翻译类论文

英语专业毕业论文翻译 类论文 Document number:NOCG-YUNOO-BUYTT-UU986-1986UT

毕业论文(设计)Title:The Application of the Iconicity to the Translation of Chinese Poetry 题目:象似性在中国诗歌翻译中的应用 学生姓名孔令霞 学号 BC09150201 指导教师祁晓菲助教 年级 2009级英语本科(翻译方向)二班 专业英语 系别外国语言文学系

黑龙江外国语学院本科生毕业论文(设计)任务书 摘要

索绪尔提出的语言符号任意性,近些年不断受到质疑,来自语言象似性的研究是最大的挑战。语言象似性理论是针对语言任意性理论提出来的,并在不断发展。象似性是当今认知语言学研究中的一个重要课题,是指语言符号的能指与所指之间的自然联系。本文以中国诗歌英译为例,探讨象似性在中国诗歌翻译中的应用,从以下几个部分阐述:(1)象似性的发展;(2)象似性的定义及分类;(3)中国诗歌翻译的标准;(4)象似性在中国诗歌翻译中的应用,主要从以下几个方面论述:声音象似、顺序象似、数量象似、对称象似方面。通过以上几个方面的探究,探讨了中国诗歌翻译中象似性原则的重大作用,在诗歌翻译过程中有助于得到“形神皆似”和“意美、音美、形美”的理想翻译效果。 关键词:象似性;诗歌;翻译

Abstract The arbitrariness theory of language signs proposed by Saussure is severely challenged by the study of language iconicity in recent years. The theory of iconicity is put forward in contrast to that of arbitrariness and has been developing gradually. Iconicity, which is an important subject in the research of cognitive linguistics, refers to a natural resemblance or analogy between the form of a sign and the object or concept. This thesis mainly discusses the application of the iconicity to the translation of Chinese poetry. The paper is better described from the following parts: (1) The development of the iconicity; (2) The definition and classification of the iconicity; (3) The standards of the translation to Chinese poetry; (4) The application of the iconicity to the translation of Chinese poetry, mainly discussed from the following aspects: sound iconicity, order iconicity, quantity iconicity, and symmetrical iconicity. Through in-depth discussion of the above aspects, this paper could come to the conclusion that the iconicity is very important in the translation of poetry. It is conductive to reach the ideal effect of “the similarity of form and spirit” and “the three beauties”. Key words: the iconicity; poetry; translation

大学毕业论文---软件专业外文文献中英文翻译

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外文翻译---汽车车身总布置的方法

附录 Modern car’s design always stresses people-oriented, so safety, comfort, Environmental protection and energy saving have been the design theme And target in car design. Ergonomics layout design is not only relate to the effective use of internal space and improve car’s comfort and safety Performance, but it will also impact internal and external modeling results, and further affects the vehicle's overall performance and marketability.Soergonomics’application and research during car design and development process occupy an important position.After more than 50 years of construction and development, China’s Automobile industry has become the leading power of automobile production and consumption in the world. In particular, with the rise and rapid de velopment of independent brand’s vehicles, we pay more attention To the development processes and the technical requirements of hard Points’ layout. Through the three typical processes such as modern vehicle developing Process, body development process and using ergonomic to progress Inner auto-body layout, describe ergonomic layoationship between design, Aunt design in which stage of the process of vehicle development, the red The importance of working steps. The automobile body total arrangement is the automobile design most initial is also the most essential step, is other design stage premise and the foundation, to a great extent is deciding the body design success or failure. Picks generally in the actual design process With by forward and reverse two design method (1) to design (from inside to outside law) to design method namely "humanist", is coming based on the human body arrangement tool to define the pilot and the crew member gradually rides the space and the vehicle comes to pay tribute each article the arrangement, take satisfies the human body to ride with the driving comfortableness as the premise, said simply is determined first satisfies the human body to ride under the comfortable premise, carries on the indoor arrangement first, then carries on the complete bikes external styling design again. The concrete method and the step are as follows: ①Determine 5% and 95% manikin H position and the chair by the SAE recommendation's enjoyable line or the region law adjustment traveling schedule, seat

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农村社会养老保险的现状、问题与对策研究社会保障对国家安定和经济发展具有重要作用,“城乡二元经济”现象日益凸现,农村社会保障问题客观上成为社会保障体系中极为重要的部分。建立和完善农村社会保障制度关系到农村乃至整个社会的经济发展,并且对我国和谐社会的构建至关重要。我国农村社会保障制度尚不完善,因此有必要加强对农村独立社会保障制度的构建,尤其对农村养老制度的改革,建立健全我国社会保障体系。从户籍制度上看,我国居民养老问题可分为城市居民养老和农村居民养老两部分。对于城市居民我国政府已有比较充足的政策与资金投人,使他们在物质和精神方面都能得到较好地照顾,基本实现了社会化养老。而农村居民的养老问题却日益突出,成为摆在我国政府面前的一个紧迫而又棘手的问题。 一、我国农村社会养老保险的现状 关于农村养老,许多地区还没有建立农村社会养老体系,已建立的地区也存在很多缺陷,运行中出现了很多问题,所以完善农村社会养老保险体系的必要性与紧迫性日益体现出来。 (一)人口老龄化加快 随着城市化步伐的加快和农村劳动力的输出,越来越多的农村青壮年人口进入城市,年龄结构出现“两头大,中间小”的局面。中国农村进入老龄社会的步伐日渐加快。第五次人口普查显示:中国65岁以上的人中农村为5938万,占老龄总人口的67.4%.在这种严峻的现实面前,农村社会养老保险的徘徊显得极其不协调。 (二)农村社会养老保险覆盖面太小 中国拥有世界上数量最多的老年人口,且大多在农村。据统计,未纳入社会保障的农村人口还很多,截止2000年底,全国7400多万农村居民参加了保险,占全部农村居民的11.18%,占成年农村居民的11.59%.另外,据国家统计局统计,我国进城务工者已从改革开放之初的不到200万人增加到2003年的1.14亿人。而基本方案中没有体现出对留在农村的农民和进城务工的农民给予区别对待。进城务工的农民既没被纳入到农村养老保险体系中,也没被纳入到城市养老保险体系中,处于法律保护的空白地带。所以很有必要考虑这个特殊群体的养老保险问题。

英语专业翻译类论文参考文献

参考文献 一、翻译理论与实践相关书目 谢天振主编. 《当代国外翻译理论导读》. 天津:南开大学出版社,2008. Jeremy Munday. 《翻译学导论——理论与实践》Introducing Translation Studies---Theories and Applications. 李德凤等译. 北京:商务印书馆,2007. 包惠南、包昂. 《中国文化与汉英翻译》. 北京:外文出版社, 2004. 包惠南. 《文化语境与语言翻译》. 北京:中国对外翻译出版公司. 2001. 毕继万. 《世界文化史故事大系——英国卷》. 上海:上海外语教育出版社, 2003. 蔡基刚. 《英汉汉英段落翻译与实践》. 上海:复旦大学出版社, 2001. 蔡基刚. 《英汉写作对比研究》. 上海:复旦大学出版社, 2001. 蔡基刚. 《英语写作与抽象名词表达》. 上海:复旦大学出版社, 2003. 曹雪芹、高鄂. 《红楼梦》. 陈定安. 《英汉比较与翻译》. 北京:中国对外翻译出版公司, 1991. 陈福康. 《中国译学理论史稿》(修订本). 上海:上海外语教育出版社. 2000. 陈生保. 《英汉翻译津指》. 北京:中国对外翻译出版公司. 1998. 陈廷祐. 《英文汉译技巧》. 北京:外语教学与研究出版社. 2001. 陈望道. 《修辞学发凡》. 上海:上海教育出版社, 1979. 陈文伯. 《英汉翻译技法与练习》. 北京:世界知识出版社. 1998. 陈中绳、吴娟. 《英汉新词新义佳译》. 上海:上海翻译出版公司. 1990. 陈忠诚. 《词语翻译丛谈》. 北京:中国对外翻译出版公司, 1983. 程希岚. 《修辞学新编》. 吉林:吉林人民出版社, 1984. 程镇球. 《翻译论文集》. 北京:外语教学与研究出版社. 2002. 程镇球. 《翻译问题探索》. 北京:商务印书馆, 1980. 崔刚. 《广告英语》. 北京:北京理工大学出版社, 1993. 单其昌. 《汉英翻译技巧》. 北京:外语教学与研究出版社. 1990. 单其昌. 《汉英翻译讲评》. 北京:对外贸易教育出版社. 1989. 邓炎昌、刘润清. 《语言与文化——英汉语言文化对比》. 北京:外语教学与研究出版社, 1989. 丁树德. 《英汉汉英翻译教学综合指导》. 天津:天津大学出版社, 1996. 杜承南等,《中国当代翻译百论》. 重庆:重庆大学出版社, 1994. 《翻译通讯》编辑部. 《翻译研究论文集(1894-1948)》. 北京:外语教学与研究出版社. 1984. 《翻译通讯》编辑部. 《翻译研究论文集(1949-1983)》. 北京:外语教学与研究出版社. 1984. . 范勇主编. 《新编汉英翻译教程》. 天津:南开大学出版社. 2006. 方梦之、马秉义(编选). 《汉译英实践与技巧》. 北京:旅游教育出版社. 1996. 方梦之. 《英语汉译实践与技巧》. 天津:天津科技翻译出版公司. 1994. 方梦之主编. 《译学辞典》. 上海:上海外语教育出版社. 2004. 冯翠华. 《英语修辞大全》,北京:外语教学与研究出版社, 1995. 冯庆华. 《文体与翻译》. 上海:上海外语教育出版社, 2002. 冯庆华主编. 《文体翻译论》. 上海:上海外语教育出版社. 2002. 冯胜利. 《汉语的韵律、词法与句法》. 北京:北京大学出版社, 1997. 冯志杰. 《汉英科技翻译指要》. 北京:中国对外翻译出版公司. 1998. 耿占春. 《隐喻》. 北京:东方出版社, 1993.

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本科毕业设计(论文)中英文对照翻译 院(系部)电气工程与自动化 专业名称电子信息工程 年级班级 04级7班 学生姓名 指导老师

Infrared Remote Control System Abstract Red outside data correspondence the technique be currently within the scope of world drive extensive usage of a kind of wireless conjunction technique,drive numerous hardware and software platform support. Red outside the transceiver product have cost low, small scaled turn, the baud rate be quick, point to point SSL, be free from electromagnetism thousand Raos etc.characteristics, can realization information at dissimilarity of the product fast, convenience, safely exchange and transmission, at short distance wireless deliver aspect to own very obvious of advantage.Along with red outside the data deliver a technique more and more mature, the cost descend, red outside the transceiver necessarily will get at the short distance communication realm more extensive of application. The purpose that design this system is transmit cu stomer’s operation information with infrared rays for transmit media, then demodulate original signal with receive circuit. It use coding chip to modulate signal and use decoding chip to demodulate signal. The coding chip is PT2262 and decoding chip is PT2272. Both chips are made in Taiwan. Main work principle is that we provide to input the information for the PT2262 with coding keyboard. The input information was coded by PT2262 and loading to high frequent load wave whose frequent is 38 kHz, then modulate infrared transmit dioxide and radiate space outside when it attian enough power. The receive circuit receive the signal and demodulate original information. The original signal was decoded by PT2272, so as to drive some circuit to accomplish

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