机械毕业设计英文外文翻译485微处理器

Microprocessors

A microprocessor is a computation engine that is fabricated on a single chip. The first microprocessor was the Intel 4004, introduced in 1971 .The 4004 was not very powerful – all it could do was add and subtract, and it could only do that 4 bits at a time. But it was amazing that everything was on one chip. Prior to the 4004, engineers built computers either from collections of chips or from discrete components. The 4004 powered one of the first portable electronic calculators.

The first microprocessor to make it into a home computer was the Intel 8080, a complete 8-bit computer on the chip, introduced in 1974. The first microprocessor to make a real splash in the market was the Intel 8088 , introduced in 1979 and incorporated into the IBM PC. The PC market moved from the 8088 to the 80286 to the 80386 to the 80486 to the Pentium to the Pentium II to the Pentium III to the Pentium 4. All of these microprocessors are made by Intel and all of them are improvements on the basic design of the 8088. The Pentium 4 can execute any piece of code that ran on the original 8088, but it does it about 5,000 times faster!

The following table shows the differences between the different processors that Intel has introduced over the years.

Table1.2

From this table you can see that, in general, there is a relationship between clock speed and MIPS. The maximum clock speed is a function of the manufacturing process and delays within the chip. There is also a relationship between the number of transistors and MIPS. For example, the 8088 clocked at 5 MHz but only executed at 0.33 MIPS(about one instruction per 15 clock cycles). Modern processors can often execute at a rate of two instructions per clock cycle. That improvement is directly related to the number of

transistors on the chip.

Inside a Microprocessor A microprocessor executes a collection of machine instructions that tell the processor what to do. Based on the instruction, a microprocessor does three basic things:

1. Using its ALU (Arithmetic/Logic Unit), a microprocessor can perform mathematical operations like addition, subtraction, multiplication and division. Modern Microprocessors contain complete floating point processors that can perform extremely sophisticated operations on large floating point numbers.

2. A microprocessor can move data from one memory location to another.

3. A microprocessor can make decisions and jump to a new set of instructions based on those decisions.

These may be very sophisticated things that a microprocessor does, but those are its three basic activities. The following diagram shows an extremely simple microprocessor capable of doing those three things:

This microprocessor has an address bus that sends an address to memory, a data bus that can send data to memory or receive data from memory, an RD (read) and WR (write) line to tell the memory whether it wants to set or get the addressed location, a clock line that lets a clock pulse sequence the processor and a reset[4] line that resets

the program counter to zero (or whatever) and restarts execution. And let’s assume that both the address and data buses are 8 bits wide here.

Here are the components of this simple microprocessor (Figure 1.1):

Figure 1.1

1.Registers A, B and C are simply latches made out of flip – flops.

2.The address latch is just like registers A, B and C.

3.The program counter is a latch with the extra ability to increment by 1 when told to do so, and also to reset to zero when told to do so.

4.The ALU could be as simple as an 8 - bit adder, or it might be able to add, subtract, multiply and divide 8 – bit values. Let’s assume the latter here.

5.The test register is a special latch that can hold values from comparisons performed in the ALU. An ALU can normally compare two

numbers and determine if they are equal, if one is greater than the other, etc. The test register can also normally hold a carry bit from the last stage of the adder. It stores these values in flip-flops and then the instruction decoder can use the values to make decisions.

6.There are six boxes marked “3-State” in the diagram. These are tri-state buffers[5]. A tri-state buffer can pass a 1, a 0 or it can essentially disconnect its output. A tri-state buffer allows multiple outputs to connect to a wire, but only one of them to actually drive a 1 or a 0 onto the line.

7.The instruction register and instruction decoder are responsible for controlling all of the other components.

Although they are not shown in this diagram, there would be control lines from the instruction decoder that would:

1.T ell the A register to latch the value currently on the data bus

2.T ell the B register to latch the value currently on the data bus

3.T ell the C register to latch the value currently on the data bus

4.T ell the program counter register to latch the value currently on the data bus

5.T ell the address register to latch the value currently on the data bus

6.T ell the instruction register to latch the value currently on the data bus

7.T ell the program counter to increment

8.T ell the program counter to reset to zero

9.A ctivate any of the six tri-state buffers (six separate lines)

10.Tell the ALU what operation to perform

11.Tell the test register to latch the ALU’s test bibs

12.Activate the RD line

13.Activate the WR line

Coming into the instruction decoder are the bits from the test register and the clock line, as well as the bits from the instruction register.

RAM and ROM the address and data buses, as well as the RD and WR lines connect either to RAM or ROM-generally both. In our sample microprocessor, we have an address bus 8 bits wide and a data bus 8 bits wide. That means that the microprocessor can address (28) 256 bytes of memory, and it can read or write 8 bits of the memory at a time. Let’s assume that this simple microprocessor has 128 bytes of ROM starting at address 0 and 128 bytes of RAM starting at address 128.

ROM stands for read-only memory. A ROM chip is programmed with a permanent collection of pre-set bytes. The address bus tells the ROM chip which byte to get and place on the data bus. When the RD line changes state, the ROM chip presents the selected byte onto the

data bus.

RAM stands for random-access memory. RAM contains bytes of information, and the microprocessor can read or write to those bytes depending on whether the RD or WR line is signaled. One problem with today’s RAM chips is that they forget everything once the power goes off. That is why the computer needs ROM.

By the way, nearly all computers contain some amount of ROM (it is possible to create a simple computer that contains no RAM-many microcontrollers do this by placing a handful of RAM bytes on the processor chip itself-but generally impossible to create one that contains no ROM). On a PC, the ROM is called the BIOS (Basic Input/Output System). When the microprocessor starts, it begins executing instructions it finds in the BIOS. The BIOS instructions do things like test the hardware in the machine, and then it goes to the hard disk to fetch the boot sector. This boot sector is another small program, and the BIOS stores it in RAM after reading it off the disk. The microprocessor then begins executing the boot sector’s instructions from RAM. The boot sector program will tell the microprocessor to fetch something else from the hard disk into RAM, which the microprocessor then executes, and so on. This is how the microprocessor loads and executes the entire operating system.

Microprocessor Instructions Even the incredibly simple

microprocessor shown here will have a fairly large set of instructions that it can perform. The collection of instructions is implemented as bit patterns, each one of which has a different meaning when loaded into the instruction register. Humans are not particularly good at remembering bit patterns, so a set of short words are defined to represent the different bit patterns. This collection of words is called the assembly language of the processor. An assembler can translate the words into their bit patterns very easily, and then the output of the assembler is placed in memory for the microprocessor to execute. If you use C language programming, a C compiler will translates the C code into assembly language.

So now the question is, “How do all of these instructions look in ROM?”Each of these assembly language instructions must be represented by a binary number . These numbers are known as opcodes. The instruction decoder needs to turn each of the opcodes into a set of signals that drive the different components inside the microprocessor. Let’s take the ADD instruction as an example and look at what it needs to do:

During the first clock cycle, we need to actually load the instruction. Therefore the instruction decoder needs to:

Activate the tri-state buffer for the program counter

Activate the RD line

Activate the data-in tri-state buffer

Latch the instruction into the instruction register

During the second clock cycle, the ADD instruction is decoded. It needs to do very little:

Set the operation of the ALU to addition

Latch the output of the ALU into the C register

During the third clock cycle, the program counter is incremented (in theory this could be overlapped into the second clock cycle).

Every instruction can be broken down as a set of sequenced operations like these that manipulate the components of the microprocessor in the proper order. Some instructions, like this ADD instruction, might take two or three clock cycles. Others might take five or six clock cycles.

Microprocessor Performance The number of transistors available has a huge effect on the performance of a processor. As seen earlier, a typical instruction in a processor like an 8088 took 15 clock cycles to execute. Because of the design of the multiplier, it took approximately 80 cycles just to do one 16-bit multiplication on the 8088. With more transistors, much more powerful multipliers capable of single-cycle speeds become possible.

More transistors also allow for a technology called pipelining[6]. In a pipelined architecture, instruction execution overlaps. So even

though it might take five clock cycles to execute each instruction, there can be five instructions in various stages of execution simultaneously. That way it looks like one instruction completes every clock cycle.

Many modern processors have multiple instruction decoders, each with its own pipeline. This allows for multiple instruction streams, which means that more than one instruction can complete during each clock cycle. This technique can be quite complex to implement, so it takes lots of transistors.

The trend in processor design has been toward full 32-bit ALUs with fast floating point processors built in and pipelined execution with multiple instruction streams. There has also been a tendency toward special instructions that make certain operations particularly efficient. There has also been the addition of hardware virtual memory support and L1 caching on the processor chip. All of these trends push up the transistor count, leading to the multi-million transistor powerhouses available today. These processors can execute about one billion instructions per second!

微处理器

微处理器是建在一块芯片上的一个计算器，1971年因特尔公司推出世界上第一款微处理器Intel4004。Intel4004功能不齐全，它只能做加减，并且一次只能处理4位，但令人吃惊的是一切都在一块芯片上。在Intel 4004之前，工程师利用芯片或其他零部件开发计算机，从此揭开了微型计算机发展的序幕。

1974年，利用Intel8088微处理开始生产家用电脑，它能处理8个二进制数，1979年推出的Intel8088，第一次打开了市场。IBM公司运用这块芯片推出了个人电脑，电脑发展经历了8088、80286、80386、80486、奔腾、奔腾II、奔腾III、奔腾4，所有这些微处理都是因特尔公司生产的，它们都是在8088的设计基础上开发的，奔腾4能执行8088上的任一套指令，但是它比8088快5000倍。

从以下表格我们可以看出因特尔公司近几年来所生产的各种处理器。

（表格2）

从这个表中，大体可以看出时钟频率和MIPS之间存在一定的关系，最大的时钟频率是生产进程的一个函数，并且它在芯片内会延迟，晶体管和MIPS 之间有一定的关系，例如8088在5兆赫兹时就运行一次，但只是以0.33MIPS 的速度来执行（大于每15时钟周期执行一条指令）。现在的处理器通常能达到每一个时钟周期执行两条指令的速度，那种运算速度的提高与芯片上的晶体管数量有直接关系。

微处理器的内部结构：微处理器执行告诉处理器该做什么的一系列的机器指令，在这个指令的基础上，微处理器完成3个基本的功能：

1、微处理器用它的算术逻辑单元，能够完成像加减乘除这一系列算术操作，现在的微处理器包含有完整的浮点处理器，它们能够完成非常复杂的浮点数的操作。

2、微处理器能把数据从一个存储单元移到另一个存储单元。

3、微处理器能做出决定，并且在那些决定的基础上发出一系列新的指令。

这些或许就是微处理器能完成的复杂的功能，但那些仅是它的3个基本功能，下面的图表说明微处理器是如何执行这些简单功能的：微处理器有地址总线，它把地址送到储存器，它还有一个数据总线，把数据送到储存器或者从储存器里接收数据，它也有读写总线，告诉储存器是想设置还是想取出这个定了位置的储存单元，它还有时钟线，告诉时钟脉冲记录处理器的结果，以及重新设置线把编码器重新设置到零（或者其他什么的）以及重新执行命令。我们假定这儿的位置和数据总线均为8位宽。下面是这个简单微处理器的结构表：（图表1.1）

图表1.1

1、记录器A，B和C 都是构成触发器的简单的锁存器。

2、位置锁恰好记录器A，B和C。

3、编码计算器是具有特别递增能力的锁，当接到指令时，它就增加1或者重新设置到零。

4、数据逻辑单元可能和8位的加法器一样简单，或者它可能会做加、减、乘和除8位数值，我们假定这儿属于后者。

5、检测记录器是一个特殊的锁，它能够把经过比较的数值锁在算术逻辑单元里，算术逻辑单元就能正常的比较两个数字，并判断他们是否相等，是否一个大于另一个等，检测记录器也能正常锁住一个阶段加法的进位位，它把这些数值储存在触发器上，然后信息译码器能用这些数值来做出判断。

6、图表中6个标注了“3—State”的方框，这些是三态缓冲器，它能传递a 1 ，a 0 或者它能基本上断开它信息的输出，它允许多个信息输出，连接到电源线，但是他们中只有一个能准确驱动a 1 或a 0 到流水线上去。

7、信息记录器和译码器要控制其余所有的部件。

虽然这些图表上没有显示这些结构，但是信息译码里将有控制线做以下事情：

1、告诉A记录器锁定当前数据总线上的数值

2、告诉B记录器锁定当前数据总线上的数值

3、告诉C记录器锁定当前数据总线上的数值

4、告诉编码计算器锁定当前数据总线上的数值

5、告诉位地址记录器锁定当前数据总线上的数值

6、告诉信息记录器锁定当前数据总线上的数值

7、告诉编码计算器增加数值

8、告诉编码计算器重新设置到零

9、激活6个三态缓冲器中的任意一个

10、告诉算术逻辑单元该执行什么指令

11、告诉检测记录器锁定算术逻辑单元的检测结果

12、激活RD线

13、激活WR线

进入信息译码器的是那些检测记录器，时钟流水线以及信息记录器里面的二进制数字行大约十亿条指令。

随机存贮器、只读存贮器、位址和数据总线。读、写一般说来都与随机存贮及只读存贮有关。在我们的样本微处理器中，我们有8位总线地址宽，8位数据总线宽，那意味着微处理器能存入（28）256个字节，它一次能读或写8个二进字位，我们假定这个简单的微处理器只读存贮0开始的位置上有128

个字节及随机存贮在128开始的位置上有128个字节。

ROM代表只读存贮器。ROM芯片是用来永久性收集预置字节的位总线告诉ROM芯片取哪个字节及放在哪条数据总线上。当RD线变化状态时，ROM 芯片就会把被选择的字节呈现到数据总线上去。

RAM代表随机存贮器，RAM包括信息字节微处理器能读或写给那些依靠RD或WR线是否注册的字节。RAM芯片的一个问题就是当断掉电源时，它上面的一切信息就不会保存下来那就是计算机需要ROM的原因。

顺便说一下，几乎所有的计算机都包括一定量的ROM（开发一个不包含RAM的简单电脑是可能的——许多微控制器通过在处理器芯片本身上面放少量RAM字节就可以完成，——但一般说来，一个不包含ROM的电脑是不可能的）。在PC机上，ROM被叫做BI0S（基本输入/输出系统）当微处理器开始运行时，它就开始执行它在BIOS中找到的指令。BIOS指令做一些检查机器硬件是否出故障的事情，然后此指令到硬盘上去获取引导程序扇区这个引导程序。扇区是另一个小程序，BIOS从磁盘上读取后把它存入RAM微处理器，然后开始从RAM上执行引导程序扇区的指令。引导程序将告诉微处理器到硬盘上去读取一些别的信息存贮到RAM。在那儿，微处理器然后执行等等，这就是微处理器读取和执行的整个操作系统。

这儿显示的相当简单的微处理器将有它能执行的相当大数量的指令，这些指令作为二进制数字符来执行。其中的每一个都有不同的意思当被载入信息记录器时人类特别不善于记住二进字符，这些词语被叫做处理的汇编语言。汇编器能非常容易地把这些词语翻译成它们的字符，然后，汇编器的输出就被放在存贮器里供微处理器执行。如果你用C语言编程、C编译程序将把C 编码译成汇编语言。

那么现在问题就在于所有这些指令在ROM中如何呈现，每一个这些汇编语言指令都必须代表二进制的数。这些数字就叫做操作码，这个指令译码器需要将每一个Opcodes变成一套指令。它们的驱动微处器内部的不同部件，咱们用ADD指令做例子来看看需要做的一切。

在第一个时钟周期中，我们需要准确的读取指令，因此指令解码器需要为简码计数器激活三态缓冲器，激活RD线，激活三态缓冲器里的数据线把指令锁定在指令记录器。

在第二个时钟周期中，ADD指令被编译了，它几乎不需要做什么。

把ALU操作看到加的位置上。

把ALU的输出锁进C寄存器。

在第三个时钟周期，编码的数量在递增，C理论上说，这可能与第二个时钟周期重叠每一个指令都会像那些以适当顺序伪造的微处理一样作为结果指

令出故障，有些指令，像ADD命令，可能花二、三个时钟周期，另外的可能要花五、六个时钟周期。

微处理器的操作：

可用的晶体管数量对处理器的操作有巨大的影响，正如早就预见到的像8088处理器里的主要指令花了15个时钟周期来完成，由于在8088上安装了乘法器，做一个16个二进制的乘法花了大约80个时钟周期。随着晶体管的增加，计算能力更强的乘法器具有单一周期的能力，更多的晶体管也考虑到一个叫做流水线技术，在一个流水线系统结构中，有些指令执行要重叠，因此尽管可能花5个时钟周期来执行一个指令。但可能有5个不同的进程的指令在同时执行，那样看起来好像一个指令完成每一个时钟周期。

许多现代的处理器有多个指令解码器，每一个都有自己的流水线。这考虑到了多条指令，那意味着在每一个时钟周期中，不只完成一个指令，这个技术可能对于执行来说相当复杂，因此它运用了许多晶体管。

在处理器设计过程中已趋向于32-bit算术逻辑单元。带有快速浮点处理器及各种指令的流水线，也趋向于特殊的指令，使某种操作特别有效，也有附有实质存贮的硬件及常于处理器芯片处的L1。所有这些趋向推动了晶体数，促成了数百万今天可用的晶体群。这些处理器每秒钟能执行大约十亿条指令。

冲压模具技术外文翻译(含外文文献)

前言 在目前激烈的市场竞争中，产品投入市场的迟早往往是成败的关键。模具是高质量、高效率的产品生产工具，模具开发周期占整个产品开发周期的主要部分。因此客户对模具开发周期要求越来越短，不少客户把模具的交货期放在第一位置，然后才是质量和价格。因此，如何在保证质量、控制成本的前提下加工模具是值得认真考虑的问题。模具加工工艺是一项先进的制造工艺，已成为重要发展方向，在航空航天、汽车、机械等各行业得到越来越广泛的应用。模具加工技术，可以提高制造业的综合效益和竞争力。研究和建立模具工艺数据库，为生产企业提供迫切需要的高速切削加工数据，对推广高速切削加工技术具有非常重要的意义。本文的主要目标就是构建一个冲压模具工艺过程，将模具制造企业在实际生产中结合刀具、工件、机床与企业自身的实际情况积累得高速切削加工实例、工艺参数和经验等数据有选择地存储到高速切削数据库中，不但可以节省大量的人力、物力、财力，而且可以指导高速加工生产实践，达到提高加工效率，降低刀具费用，获得更高的经济效益。 1.冲压的概念、特点及应用 冲压是利用安装在冲压设备（主要是压力机）上的模具对材料施加压力，使其产生分离或塑性变形，从而获得所需零件（俗称冲压或冲压件）的一种压力加工方法。冲压通常是在常温下对材料进行冷变形加工，且主要采用板料来加工成所需零件，所以也叫冷冲压或板料冲压。冲压是材料压力加工或塑性加工的主要方法之一，隶属于材料成型工程术。 冲压所使用的模具称为冲压模具，简称冲模。冲模是将材料（金属或非金属）批量加工成所需冲件的专用工具。冲模在冲压中至关重要，没有符合要求的冲模，批量冲压生产就难以进行；没有先进的冲模，先进的冲压工艺就无法实现。冲压工艺与模具、冲压设备和冲压材料构成冲压加工的三要素，只有它们相互结合才能得出冲压件。 与机械加工及塑性加工的其它方法相比，冲压加工无论在技术方面还是经济方面都具有许多独特的优点，主要表现如下； (1) 冲压加工的生产效率高，且操作方便，易于实现机械化与自动化。这是

机械毕业设计英文外文翻译460数字控制 (2)

附录 科技译文： Numerical Control Numerical Control(NC) is a method of controlling the movements of machineComponents by directly inserting coded instructions in the form of numerical data(numbers and data ) into the system.The system automatically interprets these data and converts to output signals. These signals ,in turn control various machine components ,such as turning spindles on and off ,changing tools,moving the work piece or the tools along specific paths,and turning cutting fluits on and off. In order to appreciate the importer of numerical control of machines ,let’s briefly review how a process such as machining has been carried out traditionally .After studying the working drawing of a part, the operator sets up the appropriate process parameters(such as cutting speed ,feed,depth of cut,cutting fluid ,and so on),determines the sequence of operations to be performed,clamps the work piece in a workholding device such as chuck or collet ,and proceeds to make the part .Depending on part shape and the dimensional accuracy specified ,this approach usually requires skilled

机械专业毕业论文外文翻译

附录一英文科技文献翻译 英文原文： Experimental investigation of laser surface textured parallel thrust bearings Performance enhancements by laser surface texturing (LST) of parallel-thrust bearings is experimentally investigated. Test results are compared with a theoretical model and good correlation is found over the relevant operating conditions. A compari- son of the performance of unidirectional and bi-directional partial-LST bearings with that of a baseline, untextured bearing is presented showing the bene?ts of LST in terms of increased clearance and reduced friction. KEY WORDS: ?uid ?lm bearings, slider bearings, surface texturing 1. Introduction The classical theory of hydrodynamic lubrication yields linear (Couette) velocity distribution with zero pressure gradients between smooth parallel surfaces under steady-state sliding. This results in an unstable hydrodynamic ?lm that would collapse under any external force acting normal to the surfaces. However, experience shows that stable lubricating ?lms can develop between parallel sliding surfaces, generally because of some mechanism that relaxes one or more of the assumptions of the classical theory. A stable ?uid ?lm with su?cient load-carrying capacity in parallel sliding surfaces can be obtained, for example, with macro or micro surface structure of di?erent types. These include waviness [1] and protruding microasperities [2–4]. A good literature review on the subject can be found in Ref. [5]. More recently, laser surface texturing (LST) [6–8], as well as inlet roughening by longitudinal or transverse grooves [9] were suggested to provide load capacity in parallel sliding. The inlet roughness concept of Tonder [9] is based on ??e?ective clearance‘‘ reduction in the sliding direction and in this respect it is identical to the par- tial-LST concept described in ref. [10] for generating hydrostatic e?ect in high-pressure mechanical seals. Very recently Wang et al. [11] demonstrated experimentally a doubling of the load-carrying capacity for the surface- texture design by reactive ion etching of SiC

毕业设计外文翻译资料

外文出处： 《Exploiting Software How to Break Code》By Greg Hoglund, Gary McGraw Publisher : Addison Wesley Pub Date : February 17, 2004 ISBN : 0-201-78695-8 译文标题： JDBC接口技术 译文： JDBC是一种可用于执行SQL语句的JavaAPI（ApplicationProgrammingInterface应用程序设计接口）。它由一些Java语言编写的类和界面组成。JDBC为数据库应用开发人员、数据库前台工具开发人员提供了一种标准的应用程序设计接口，使开发人员可以用纯Java语言编写完整的数据库应用程序。 一、ODBC到JDBC的发展历程 说到JDBC，很容易让人联想到另一个十分熟悉的字眼“ODBC”。它们之间有没有联系呢？如果有，那么它们之间又是怎样的关系呢？ ODBC是OpenDatabaseConnectivity的英文简写。它是一种用来在相关或不相关的数据库管理系统（DBMS）中存取数据的，用C语言实现的，标准应用程序数据接口。通过ODBCAPI，应用程序可以存取保存在多种不同数据库管理系统（DBMS）中的数据，而不论每个DBMS使用了何种数据存储格式和编程接口。 1．ODBC的结构模型 ODBC的结构包括四个主要部分：应用程序接口、驱动器管理器、数据库驱动器和数据源。应用程序接口：屏蔽不同的ODBC数据库驱动器之间函数调用的差别，为用户提供统一的SQL编程接口。 驱动器管理器：为应用程序装载数据库驱动器。 数据库驱动器：实现ODBC的函数调用，提供对特定数据源的SQL请求。如果需要，数据库驱动器将修改应用程序的请求，使得请求符合相关的DBMS所支持的文法。 数据源：由用户想要存取的数据以及与它相关的操作系统、DBMS和用于访问DBMS的网络平台组成。 虽然ODBC驱动器管理器的主要目的是加载数据库驱动器，以便ODBC函数调用，但是数据库驱动器本身也执行ODBC函数调用，并与数据库相互配合。因此当应用系统发出调用与数据源进行连接时，数据库驱动器能管理通信协议。当建立起与数据源的连接时，数据库驱动器便能处理应用系统向DBMS发出的请求，对分析或发自数据源的设计进行必要的翻译，并将结果返回给应用系统。 2．JDBC的诞生 自从Java语言于1995年5月正式公布以来，Java风靡全球。出现大量的用java语言编写的程序，其中也包括数据库应用程序。由于没有一个Java语言的API，编程人员不得不在Java程序中加入C语言的ODBC函数调用。这就使很多Java的优秀特性无法充分发挥，比如平台无关性、面向对象特性等。随着越来越多的编程人员对Java语言的日益喜爱，越来越多的公司在Java程序开发上投入的精力日益增加，对java语言接口的访问数据库的API 的要求越来越强烈。也由于ODBC的有其不足之处，比如它并不容易使用，没有面向对象的特性等等，SUN公司决定开发一Java语言为接口的数据库应用程序开发接口。在JDK1．x 版本中，JDBC只是一个可选部件，到了JDK1．1公布时，SQL类包（也就是JDBCAPI）

机械设计外文翻译(中英文)

机械设计理论 机械设计是一门通过设计新产品或者改进老产品来满足人类需求的应用技术科学。它涉及工程技术的各个领域，主要研究产品的尺寸、形状和详细结构的基本构思，还要研究产品在制造、销售和使用等方面的问题。 进行各种机械设计工作的人员通常被称为设计人员或者机械设计工程师。机械设计是一项创造性的工作。设计工程师不仅在工作上要有创造性，还必须在机械制图、运动学、工程材料、材料力学和机械制造工艺学等方面具有深厚的基础知识。如前所诉，机械设计的目的是生产能够满足人类需求的产品。发明、发现和科技知识本身并不一定能给人类带来好处，只有当它们被应用在产品上才能产生效益。因而，应该认识到在一个特定的产品进行设计之前，必须先确定人们是否需要这种产品。 应当把机械设计看成是机械设计人员运用创造性的才能进行产品设计、系统分析和制定产品的制造工艺学的一个良机。掌握工程基础知识要比熟记一些数据和公式更为重要。仅仅使用数据和公式是不足以在一个好的设计中做出所需的全部决定的。另一方面，应该认真精确的进行所有运算。例如，即使将一个小数点的位置放错，也会使正确的设计变成错误的。 一个好的设计人员应该勇于提出新的想法，而且愿意承担一定的风险，当新的方法不适用时，就使用原来的方法。因此，设计人员必须要有耐心，因为所花费的时间和努力并不能保证带来成功。一个全新的设计，要求屏弃许多陈旧的，为人们所熟知的方法。由于许多人墨守成规，这样做并不是一件容易的事。一位机械设计师应该不断地探索改进现有的产品的方法，在此过程中应该认真选择原有的、经过验证的设计原理，将其与未经过验证的新观念结合起来。 新设计本身会有许多缺陷和未能预料的问题发生，只有当这些缺陷和问题被解决之后，才能体现出新产品的优越性。因此，一个性能优越的产品诞生的同时，也伴随着较高的风险。应该强调的是，如果设计本身不要求采用全新的方法，就没有必要仅仅为了变革的目的而采用新方法。 在设计的初始阶段，应该允许设计人员充分发挥创造性，不受各种约束。即使产生了许多不切实际的想法，也会在设计的早期，即绘制图纸之前被改正掉。只有这样，才不致于堵塞创新的思路。通常，要提出几套设计方案，然后加以比较。很有可能在最后选定的方案中，采用了某些未被接受的方案中的一些想法。

机械毕业设计英文外文翻译204机电一体化

附录 INTEGRATION OF MACHINERY （From ELECTRICAL AND MACHINERY INDUSTRY）ABSTRACT Machinery was the modern science and technology development inevitable result, this article has summarized the integration of machinery technology basic outline and the development background .Summarized the domestic and foreign integration of machinery technology present situation, has analyzed the integration of machinery technology trend of development. Key word：integration of machinery ，technology，present situation ，product t，echnique of manufacture ，trend of development 0. Introduction modern science and technology unceasing development, impelled different discipline intersecting enormously with the seepage, has caused the project domain technological revolution and the transformation .In mechanical engineering domain, because the microelectronic technology and the computer technology rapid development and forms to the mechanical industry seepage the integration of machinery, caused the mechanical industry the technical structure, the product organization, the function and the constitution, the production method and the management system has had the huge change, caused the industrial production to enter into “the integration of machinery” by “the machinery electrification” for the characteristic development phase. 1. Integration of machinery outline integration of machinery is refers in the organization new owner function, the power function, in the information processing function and the control function introduces the electronic technology, unifies the system the mechanism and the computerization design and the software which constitutes always to call. The integration of machinery development also has become one to have until now own system new discipline, not only develops along with the science and technology, but also entrusts with the new content .But its basic characteristic may summarize is: The integration of machinery is embarks from the system viewpoint, synthesis community technologies and so on utilization mechanical technology, microelectronic technology, automatic control technology,

机械类毕业设计外文翻译

本科毕业论文(设计) 外文翻译 学院：机电工程学院 专业：机械工程及自动化 姓名：高峰 指导教师：李延胜 2011年05 月10日 教育部办公厅 Failure Analysis，Dimensional Determination And

Analysis，Applications Of Cams INTRODUCTION It is absolutely essential that a design engineer know how and why parts fail so that reliable machines that require minimum maintenance can be designed．Sometimes a failure can be serious，such as when a tire blows out on an automobile traveling at high speed．On the other hand，a failure may be no more than a nuisance．An example is the loosening of the radiator hose in an automobile cooling system．The consequence of this latter failure is usually the loss of some radiator coolant，a condition that is readily detected and corrected．The type of load a part absorbs is just as significant as the magnitude．Generally speaking，dynamic loads with direction reversals cause greater difficulty than static loads，and therefore，fatigue strength must be considered．Another concern is whether the material is ductile or brittle．For example，brittle materials are considered to be unacceptable where fatigue is involved． Many people mistakingly interpret the word failure to mean the actual breakage of a part．However，a design engineer must consider a broader understanding of what appreciable deformation occurs．A ductile material，however will deform a large amount prior to rupture．Excessive deformation，without fracture，may cause a machine to fail because the deformed part interferes with a moving second part．Therefore，a part fails(even if it has not physically broken)whenever it no longer fulfills its required function．Sometimes failure may be due to abnormal friction or vibration between two mating parts．Failure also may be due to a phenomenon called creep，which is the plastic flow of a material under load at elevated temperatures．In addition，the actual shape of a part may be responsible for failure．For example，stress concentrations due to sudden changes in contour must be taken into account．Evaluation of stress considerations is especially important when there are dynamic loads with direction reversals and the material is not very ductile． In general，the design engineer must consider all possible modes of failure，which include the following． ——Stress ——Deformation ——Wear ——Corrosion ——Vibration ——Environmental damage ——Loosening of fastening devices

毕业设计外文翻译附原文

外文翻译 专业机械设计制造及其自动化学生姓名刘链柱 班级机制111 学号1110101102 指导教师葛友华

外文资料名称： Design and performance evaluation of vacuum cleaners using cyclone technology 外文资料出处：Korean J. Chem. Eng., 23(6), (用外文写) 925-930 (2006) 附件： 1.外文资料翻译译文 2.外文原文

应用旋风技术真空吸尘器的设计和性能介绍 吉尔泰金，洪城铱昌，宰瑾李， 刘链柱译 摘要：旋风型分离器技术用于真空吸尘器 - 轴向进流旋风和切向进气道流旋风有效地收集粉尘和降低压力降已被实验研究。优化设计等因素作为集尘效率，压降，并切成尺寸被粒度对应于分级收集的50％的效率进行了研究。颗粒切成大小降低入口面积，体直径，减小涡取景器直径的旋风。切向入口的双流量气旋具有良好的性能考虑的350毫米汞柱的低压降和为1.5μm的质量中位直径在1米3的流量的截止尺寸。一使用切向入口的双流量旋风吸尘器示出了势是一种有效的方法，用于收集在家庭中产生的粉尘。 摘要及关键词：吸尘器; 粉尘; 旋风分离器 引言 我们这个时代的很大一部分都花在了房子，工作场所，或其他建筑，因此，室内空间应该是既舒适情绪和卫生。但室内空气中含有超过室外空气因气密性的二次污染物，毒物，食品气味。这是通过使用产生在建筑中的新材料和设备。真空吸尘器为代表的家电去除有害物质从地板到地毯所用的商用真空吸尘器房子由纸过滤，预过滤器和排气过滤器通过洁净的空气排放到大气中。虽然真空吸尘器是方便在使用中，吸入压力下降说唱空转成比例地清洗的时间，以及纸过滤器也应定期更换，由于压力下降，气味和细菌通过纸过滤器内的残留粉尘。 图1示出了大气气溶胶的粒度分布通常是双峰形，在粗颗粒（>2.0微米）模式为主要的外部来源，如风吹尘，海盐喷雾，火山，从工厂直接排放和车辆废气排放，以及那些在细颗粒模式包括燃烧或光化学反应。表1显示模式，典型的大气航空的直径和质量浓度溶胶被许多研究者测量。精细模式在0.18?0.36 在5.7到25微米尺寸范围微米尺寸范围。质量浓度为2?205微克，可直接在大气气溶胶和 3.85至36.3μg/m3柴油气溶胶。

机械类外文翻译

机械类外文翻译 塑料注塑模具浇口优化 摘要:用单注塑模具浇口位置的优化方法，本文论述。该闸门优化设计的目的是最大限度地减少注塑件翘曲变形，翘曲，是因为对大多数注塑成型质量问题的关键，而这是受了很大的部分浇口位置。特征翘曲定义为最大位移的功能表面到表面的特征描述零件翘曲预测长度比。结合的优化与数值模拟技术，以找出最佳浇口位置，其中模拟armealing算法用于搜索最优。最后，通过实例讨论的文件，它可以得出结论，该方法是有效的。 注塑模具、浇口位臵、优化、特征翘曲变形关键词: 简介 塑料注射成型是一种广泛使用的，但非常复杂的生产的塑料产品，尤其是具有高生产的要求，严密性，以及大量的各种复杂形状的有效方法。质量ofinjection 成型零件是塑料材料，零件几何形状，模具结构和工艺条件的函数。注塑模具的一个最重要的部分主要是以下三个组件集:蛀牙，盖茨和亚军，和冷却系统。拉米夫定、Seow(2000)、金和拉米夫定(2002) 通过改变部分的尼斯达到平衡的腔壁厚度。在平衡型腔充填过程提供了一种均匀分布压力和透射电镜,可以极大地减少高温的翘曲变形的部分～但仅仅是腔平衡的一个重要影响因素的一部分。cially Espe,部分有其功能上的要求,其厚度通常不应该变化。 pointview注塑模具设计的重点是一门的大小和位臵,以及流道系统的大小和布局。大门的大小和转轮布局通常被认定为常量。相对而言,浇口位臵与水口大小布局也更加灵活,可以根据不同的零件的质量。 李和吉姆(姚开屏,1996a)称利用优化流道和尺寸来平衡多流道系统为multiple 注射系统。转轮平衡被形容为入口压力的差异为一多型腔模具用相同的蛀牙,也存

机械类毕业设计外文文献翻译

沈阳工业大学工程学院 毕业设计（论文）外文翻译 毕业设计（论文）题目：工具盒盖注塑模具设计 外文题目：Friction , Lubrication of Bearing 译文题目：轴承的摩擦与润滑 系（部）：机械系 专业班级：机械设计制造及其自动化0801 学生姓名：王宝帅 指导教师：魏晓波 2010年10 月15 日

外文文献原文： Friction , Lubrication of Bearing In many of the problem thus far , the student has been asked to disregard or neglect friction . Actually , friction is present to some degree whenever two parts are in contact and move on each other. The term friction refers to the resistance of two or more parts to movement. Friction is harmful or valuable depending upon where it occurs. friction is necessary for fastening devices such as screws and rivets which depend upon friction to hold the fastener and the parts together. Belt drivers, brakes, and tires are additional applications where friction is necessary. The friction of moving parts in a machine is harmful because it reduces the mechanical advantage of the device. The heat produced by friction is lost energy because no work takes place. Also , greater power is required to overcome the increased friction. Heat is destructive in that it causes expansion. Expansion may cause a bearing or sliding surface to fit tighter. If a great enough pressure builds up because made from low temperature materials may melt. There are three types of friction which must be overcome in moving parts: (1)starting, (2)sliding, and(3)rolling. Starting friction is the friction between two solids that tend to resist movement. When two parts are at a state of rest, the surface irregularities of both parts tend to interlock and form a wedging action. To produce motion in these parts, the wedge-shaped peaks and valleys of the stationary surfaces must be made to slide out and over each other. The rougher the two surfaces, the greater is starting friction resulting from their movement . Since there is usually no fixed pattern between the peaks and valleys of two mating parts, the irregularities do not interlock once the parts are in motion but slide over each other. The friction of the two surfaces is known as sliding friction. As shown in figure ,starting friction is always greater than sliding friction . Rolling friction occurs when roller devces are subjected to tremendous stress which cause the parts to change shape or deform. Under these conditions, the material in front of a roller tends to pile up and forces the object to roll slightly uphill. This changing of shape , known as deformation, causes a movement of molecules. As a result ,heat is produced from the added energy required to keep the parts turning and overcome friction. The friction caused by the wedging action of surface irregularities can be overcome

毕业设计外文翻译

毕业设计（论文） 外文翻译 题目西安市水源工程中的 水电站设计 专业水利水电工程 班级 学生 指导教师 2016年

研究钢弧形闸门的动态稳定性 牛志国 河海大学水利水电工程学院，中国南京，邮编210098 nzg_197901@https://www.docsj.com/doc/d95734998.html,，niuzhiguo@https://www.docsj.com/doc/d95734998.html, 李同春 河海大学水利水电工程学院，中国南京，邮编210098 ltchhu@https://www.docsj.com/doc/d95734998.html, 摘要 由于钢弧形闸门的结构特征和弹力，调查对参数共振的弧形闸门的臂一直是研究领域的热点话题弧形弧形闸门的动力稳定性。在这个论文中，简化空间框架作为分析模型，根据弹性体薄壁结构的扰动方程和梁单元模型和薄壁结构的梁单元模型，动态不稳定区域的弧形闸门可以通过有限元的方法，应用有限元的方法计算动态不稳定性的主要区域的弧形弧形闸门工作。此外，结合物理和数值模型，对识别新方法的参数共振钢弧形闸门提出了调查，本文不仅是重要的改进弧形闸门的参数振动的计算方法，但也为进一步研究弧形弧形闸门结构的动态稳定性打下了坚实的基础。 简介 低举升力，没有门槽，好流型，和操作方便等优点，使钢弧形闸门已经广泛应用于水工建筑物。弧形闸门的结构特点是液压完全作用于弧形闸门，通过门叶和主大梁，所以弧形闸门臂是主要的组件确保弧形闸门安全操作。如果周期性轴向载荷作用于手臂，手臂的不稳定是在一定条件下可能发生。调查指出:在弧形闸门的20次事故中，除了极特殊的破坏情况下，弧形闸门的破坏的原因是弧形闸门臂的不稳定;此外，明显的动态作用下发生破坏。例如:张山闸，位于中国的江苏省，包括36个弧形闸门。当一个弧形闸门打开放水时，门被破坏了，而其他弧形闸门则关闭，受到静态静水压力仍然是一样的，很明显，一个动态的加载是造成的弧形闸门破坏一个主要因素。因此弧形闸门臂的动态不稳定是造成弧形闸门(特别是低水头的弧形闸门)破坏的主要原是毫无疑问。

机械图纸中英文翻译汇总

近几年，我厂和英国、西班牙的几个公司有业务往来，外商传真发来的图纸都是英文标注，平时阅看有一定的困难。下面把我们积累的几点看英文图纸的经验与同行们交流。 1标题栏 英文工程图纸的右下边是标题栏（相当于我们的标题栏和部分技术要求），其中有图纸名称（TILE）、设计者（DRAWN）、审查者（CHECKED）、材料（MATERIAL）、日期（DATE）、比例（SCALE）、热处理（HEAT TREATMENT）和其它一些要求，如： 1)TOLERANCES UNLESS OTHERWISE SPECIFIAL 未注公差。 2)DIMS IN mm UNLESS STATED 如不做特殊要求以毫米为单位。 3)ANGULAR TOLERANCE±1°角度公差±1°。 4)DIMS TOLERANCE±0.1未注尺寸公差±0.1。 5)SURFACE FINISH 3.2 UNLESS STATED未注粗糙度3.2。 2常见尺寸的标注及要求 2.1孔（HOLE）如： （1）毛坯孔：3"DIAO+1CORE 芯子3"0+1; （2）加工孔：1"DIA1"; （3）锪孔：锪孔(注C＇BORE=COUNTER BORE锪底面孔); （4）铰孔：1"/4 DIA REAM铰孔1"/4; （5）螺纹孔的标注一般要表示出螺纹的直径，每英寸牙数（螺矩）、螺纹种类、精度等级、钻深、攻深，方向等。如： 例1.6 HOLES EQUI-SPACED ON 5"DIA (6孔均布在5圆周上（EQUI-SPACED=EQUALLY SPACED均布） DRILL 1"DIATHRO＇ 钻1"通孔（THRO＇=THROUGH通） C/SINK22×6DEEP 沉孔22×6 例2.TAP7"/8-14UNF-3BTHRO＇ 攻统一标准细牙螺纹，每英寸14牙，精度等级3B级 （注UNF=UNIFIED FINE THREAD美国标准细牙螺纹） 1"DRILL 1"/4-20 UNC-3 THD7"/8 DEEP 4HOLES NOT BREAK THRO钻 1"孔，攻1"/4美国粗牙螺纹，每英寸20牙，攻深7"/8,4孔不准钻通（UNC=UCIFIED COARSE THREAD 美国标准粗牙螺纹）

机械毕业设计外文翻译---装载机发展概况

外文资料翻译 学生姓名： 专业班级：机械设计制造及其自动化04级2班指导教师： 2008年6月

装载机发展概况 Abstract This paper have discussed s.s. ZL-50 type fork-lift truck mainly overall fictitious prototype design as well as some kinds of typical schoolwork operating modes imitate and emulate , include equipment and the overall parts needed build mould. In this design course, have applied ADAMS software and the software of PRO/ENGINEER. ADAMS software is used in the emulation of some kinds of schoolwork operating modes, and the software of PRO/ENGINEER is used to build mould mainly. Through the simulated emulation for some kinds of overall schoolwork operating modes, can see relatively distinctly the overall possible condition in actual schoolwork course that met , can in time modify , have reduced actual design time , have raised production efficiency. The innovation of this design Zhi is in in, imitate and have emulated fork-lift truck the 3 kinds of typical schoolwork operating mode in actual schoolwork, is effect again have imitated in actual schoolwork the hydraulic impact of use, so when being helpful to solve actual loading, the actual problem of meeting the stock that is hard to uninstall can so raise production efficiency. Key words: Fork-lift truck 、fictitious prototype , build mould, emulation, optimization、production efficiency Loader Development China's modern 20 wheel loaders began in the mid-1960s of the Z435. The aircraft as a whole rack, rear axle steering. After years of hard work, the attraction was the world's most advanced technology wheel loader on the basis of the successful development of the power of 162 KW of shovel-fit wheel loaders, stereotypes for Z450 (later ZL50), and in 1971 December 18, formally appraised by experts. Thus the birth of China's first articulated wheel loader, thus creating our industry loader formation and development history. Z450-type loader with hydraulic mechanical transmission, power shift, Shuangqiaoshan drive, hydraulic manipulation, articulated power steering, gas oil Afterburner brake wheel loaders, and other modern, the basic structure of the world's advanced level for the time . Basically represent the first generation of wheeled loading the basic structure. The aircraft in the overall performance of dynamic, and insertion force a rise of power and flexibility, manipulation of light, the higher operating efficiency of a series of advantages. 1978, Heavenly Creations by the Department in accordance with the requirements of machinery, worked out to LIUGONG Z450-based type of wheel loaders series of standards. The development of standards, with reservations Z