英文原文名《English for Die Mould Design and
Manufacturing》
英文原文版出处：北京大学出版社3月第1版
译文：
6.4自动化生产
6.4.1 介绍
自动化是一种没有人类的协助下能完成控制的技术，它是通过使用指令结合执行该指令的控制系统的程序来实现。一个自动化的程序需要只是的驱动和控制系统操作。自动化能被应用于各种领域，尤其与工业制造系联系更为紧密。最早用于工业制造中的是在1946年福特汽车公司的一名工程经理，用于描述福特生产厂的自动传送系统装置与进给机制的多样性。而具有讽刺意味的是，近来所有的现代自动化应用技术都是受控于在1964年还没使用的电脑技术。
自动化制造系统在物理产品上的工厂的操作。他们进行加工，装配，检验操作，或材料处理，在某些情况下完成更多的在同一系统中这些操作之一。之所以被称为自动化是因为其执行的是代替较低水平的人的参与与之相应的手动过程。而且在一些高度自动化的系统，几乎没有人的参与。自动化制造系统的例子包括：（1）加工零件的自动化机床
（2）自动连续生产线和类似的顺序生产系统
（3）生产制造系统中使用工业机器人进行加工或装配操作
（4）自动化材料处理和存储系统集成的制造作业
（5）用于质量控制的自动检测系统
自动化生产系统可分为三种基本类型：（1）硬性自动化，（2）可编程自动化，和（3）柔性自动化
硬性的自动化是通过一个系统中的处理的序列（或装配）操作的设备配置固定。每个环节的操作通常是简单的，可能包括普通线性或旋转的两个运动或一个远动得到简单组合。这是很多这种工序的协调与整合为一个设备，使得系统变的复杂。硬性自动化的典型特点包括：
（1）定做设计设备的初期投资高
（2）高生产效率
（3）适应产品变化相对单一
对于经济上来说硬性自动化用于大批量和高生产率的产品。与其他生产方式相比高的初期成本有着它的特点。例如硬性自动化包括生产线和自动化装配机。
在可编程自动化中，生产设备的设计有能力改变操作序列来适应不同的产品配置。操作顺序和程序控制，这是一组指令编码以便他们可以读取使系统中断。新的程序可以制备和输入设备中来生产新的产品。可编程自动化生产系统的应用低和中等批量的生产。零件和产品通常是大批量生产。生产每一批不同的新产品，系统必须对新产品系列重新编入相应的新指令。机器的相对设置也必须作出相应的改变：工具必须加载，设备必须连接到机床工作台，及所需的机器设置指令必须输入。可编程自动化的例子包括数控机床，工业机器人，可编程逻辑控制器。
柔性自动化的可编程自动化的一个扩展。柔性自动化系统是能够生产各种零件（或产品）几乎没有花费多余时间从一个制件的到另一个不同制件的转换。无需损失生产时间且没必要重新编程的系统和改变的机械辅助配件（模具，夹具，机床设置）。因此，该系统可以生产各种不同的组合和部分组合的产品而不是要求他们进行分批生产。是什么使柔性自动化可能是通过该系统处理部分之间的差异不明显。这是一个各种软件的情况下，使所需的要求之间转换的量是最小的。柔性自动化的例子是柔性制造系统进行机械加工，可以追溯到20世纪60年代后期。
6.4.2柔性制造系统
在现代制造业框架中，柔性是一个重要的特性。这意味一个制造系统是具有通用性和广泛适应性，同时也有较高的生产能力。一个柔性的制造系统是通用的，它能生产多种零件。它具有广泛适应性是因为它可以被很快的作出调整，生产完全不同的零件。
柔性制造系统（FMS）是一个高度自动化的TG（成组技术）机电池。一批处理工作站（通常是数控机床），由一个自动的材料的互连处理和存储系统，并通过一个分布式计算机来控制系统。之所以称为柔性系统是能够处理各种不同的部分风格同时在各种工作站，和图案的组合。FMS是在各种品种中，适合中批量生产。
FMS依托集团的技术原理。成组技术是相似的部件组合到一起，利用他们的设计和生产制造的理念相似，相似的零件安装到部分位置，其中每个部分位置具有相似的设计和制造特点。没有一个制造系统能够是完全柔性的，对于能在FMS 上生产的部分工序（或产品）是有限制的。FMS是在一个被定义的样式、尺寸和过程内来生产产品的。换句话说，FMS能够生产一种单独的产品或者一组受限制的产品。
FMS必须具备三种功能：（1）在系统加工的不同的工序或产品中辨认区别的功能；（2）快速地改变操作指令；（3）快速变换物理装置。
6.4.3计算机集成制造系统
计算机集成制造（CIM）是用来描述现代的方法来制造术语。虽然CIN包括许多其他先进的制造方法诸如计算机数字控制（CNC）、计算机辅助技术/计算机辅助制造（CAD/CAM）、机器人学以及及时（JIT）交货，但它仍不过是一项新技术或者是一个新概念。计算机集成制造是一种全新的制造方法，一条全新的经营之道。
为了理解CIM，有必要从现代与传统制造的比较开始。现代制造包括所有把原材料变成成品、将它们送到市场以及在工地对它们进行保障所需的活动与工艺。这些活动包括以下内容：
（1）确定对于某一产品的需求。
（2）设计一种产品来满足这一需求。
（3）获得生产这种产品所需的原材料。
（4）采用适当的工艺把原材料变成产品。
（5）把产品运送到市场。
（6）对这种产品进行维修以确保其在工地的固有性能。
可以把这种广义的现代制造观点与那种几乎全部集中于转换过程的更为狭义的传统观点来进行比较。老方法将重要的转换前的要点如市场分析研究、开发与设计以及转换后的要点包括产品交货与产品维修在内。换句话说，在老的制造方法中，只有那些发生在工厂的工艺才被认为是制造工艺。这种传统的把全面的概念分为若干独立元素的方法基本上不会随自动化的到来而改变。
就CIM而言，不仅各种元素自动化了，而且自动化也被联系在一起或集成。集成化意味着一个系统可以具有完全、瞬时的信息分享。在现代制造中，而集成化由计算机完成。而CIM则实现所有部件的集成化，包括把原材料包装成产品以及把产品送到市场。
第7章CAD/CAM/CAE
7.1 在模具设计中的计算机
CAD既可以指计算机辅助设计，又可以指计算机辅助绘图。实际上，这意味着任何一个或两个这些概念和工具，设计者都有机会使用它的两种形式。
CAD计算机辅助设计是指用计算机和外设使设计过程简化和强化。CAD计算机辅助绘图是指计算机和外部设备来产生设计过程的文件和图样。文件通常包括初步设计图，工作图纸，零件列表，和设计计算。
无论是计算机辅助设计系统还是计算机辅助绘图系统，CAD系统由三个基本部分组成：（1）硬件、（2）软件、（3）用户。CAD系统的硬件组成包括处理器、系统显示、键盘、数字转换器和绘图机。CAD系统的软件由具有设计和绘画功能的程序组成。用户就是使用硬件和软件是设计过程简化和强化的工具设计者。
图形显示是第一步，从而可将设计与计算机真正结合起来，接下来是用绘图仪画出图形。随着20世纪60年代早期的数字化平板仪的发明，我们今天所知的CAD硬件开始成形，很快计算机绘图随之得以发展。
早期的CAD系统庞大、笨重且昂贵。因为太贵了，只有大公司才用得起。在20世纪60年代末。CAD被认为有在模具设计应用的潜力和意义但不实用的革新。
但是，随之20世纪70年代硅芯片的引入，计算机开始在图形设计领域发挥作用。
硅晶片上的集成电路使得组装起来的计算机与电视机一样大小。这种“迷你”
小型机具有大型计算机的全部功能，但却小得多也相当便宜，很快又出现了更小的被称为微机的计算机。
20世纪70年代CAD软硬件技术有了长足的发展，以至于80年代初，研发与销售CAD系统已成为一个飞速增长的产业。同时CAD已由最初的新颖但不实用变成今天的一项重要发明，到了1980年，已有从微机、小型机到大型计算机用的多种CAD系统。
7.2 CAD/CAM
7.2.1 CAD
计算机辅助设计/ 计算机辅助制造（CAD/CAM）指的是将计算机应用于设计和生产过程中以提高生产率。CAD/CAM系统的核心是设计终端和相应的硬件，诸如计算机、打印机、绘图仪、磁带机和数字化仪等，设计在被完成之前始终在终端显示器上被监测，如果需要还可进行硬拷贝。含有设计数据的计算机磁带或其它控制媒介在制造、测试和质量控制过程中驱动着数控加工设备。
用于CAD/CAM的软件是储存在计算机系统中的程序集合，用来驱动各种构成硬件完成特定的任务。如生成NC（数控）加工路径、装配材料清单、在有限元模型中生成节点和单元的程序。有些软件包指的是软件（程序）模块，可分为以下四类：（1）操作系统、（2）通用程序、（3）应用程序和（4）用户程序。虽然还有其它功能模块软件，但这足以说明研发CAD/CAM系统的复杂性了。
操作系统是指为某一个或一类计算机而写的程序，为操作便利高效，将数据和程序放在系统的内存中，操作系统与输入/输出设备，如显示器、打印机及磁带打孔机的关系尤其密切。大多时候操作系统由计算机供应商提供。
虽然有争议说不存在所谓的通用程序，但一些程序的确比其它程序更常用些。例如
用高级语言像FORTRAN编写的图形程序，可以生成线、圆、抛物线等几何实体以及这些几何实体的组合，用这些基本图元实体可进行设计，设计范围包括印刷电路板、钻头夹具、固定装置等。
应用程序是专为某一特殊用途而开发的。第一个专用程序语言是1956年的自动编程工具（APT）语言，APT是为简化向数控机床输入的加工程序的编制而开发的，如图7-1所示。其它与CAD/CAM有关的专用程序有：生成有限元网格和金属板件的平面模型，这类程序通常可与系统一起买进或从软件供应商处得到。
图7-1 例如CAD在车加工显示的机加工序列
CAD/CAM系统中的用户程序是为产生专用输出结果（而研制）的专业针对性极强的软件包，如用户只要输入一些像齿数、节圆直径之类的参数，就可由用户程序自动生成齿轮。还可用另一类程序在给出刀具尺寸、材料、切削深度等信息后，计算切削时的最佳进给和转速。这类程序通常都是用户在通用软件供应商提供的软件模块基础上自己开发的。尽管用户程序可大大节约时间和精力，但不是所有的CAD/CAM软件包都有用户程序。
1. 计算机图形
计算机图形系统计算并储存物理相关的数据，以确定精确位置、尺寸标注及每个设计单元的其它特性。借助于这些相关设计数据，用户设计人员可在工件制品加工前进行复杂的工程分析、生成材料清单、生产报告、检查设计的不相容性。
利用计算机图形学，可将二维图形转换成三维线框和实体模型。
2. 线框模型
简单的线框模型是表示几何模型最经济的一种方法，在检验图形的基本属性和模型
的连续性时很有用，但在开发复杂模型时，线框模型就有局限性，实体模型可解决线框模型中出现的大部分问题。
3. 实体模型
主要有三种构造实体的技术：构造实体几何法(CSG)、边界表示法(B-Rep)和分解实体模型。
构造实体几何法(CSG)是用各种几何体素如圆柱、球面、圆锥等经过布尔（Boolean）运算后生成实体。
边界法中，先定出物件轮廓，再通过线性或径向扫描，用其中所包含的区域表示实体。
4. 分解实体模型
分解实体模型与边界法相似，但加强了构造时的有限元模型。商业化软件包中，并不单纯使用某一种方法，例如，在构造实体表达法中可能会用到边界法技术生成初始模型，而在边界法或分解法中可能会用布尔代数法，利用圆柱或圆锥去修剪模型，生成孔洞。
7.2.2 CAM
计算机辅助制造侧重于以下四方面：数控，工艺规程编制，自动化操作和生产管理。
1.数控
计算机辅助制造（CAM）中数控的重要性体现在：可用计算机从几何模型或制品直接生成数控程序。目前，这种自动化能力还仅仅限于非常对称和其它特殊形状的制品。未来，有些公司可能根本不用图纸，就可通过数据库将产品信息直接从设计传送到制造工序。由于计算机设计与制造使用同一个集成数据库，生成的计算机模型数是一样的，所以随着图纸的消失，好些问题也会随之而去。①这样即便部门之间在地域上离得很远也不影响工作，因为实际上他们是通过办公桌上的终端连在一起的。
2. 工艺规程
制定工艺规程包括从生产开始到结束的每一个工序，与计算机辅助制造相连的工艺制定系统几乎不用人工参与就可直接从几何模型数据库生成工艺过程。
3. 自动化
制造系统的自动机器人（装置）完成了许多改进，如在线装配、在线焊接和在线喷涂等。
4. 生产管理
生产管理用交互的工业数据收集以便及时获得和生产相关的信息，并用该数据计算出制造的先后次序，动态地确定下步要做的工作，从而保证标准制造程序的正常执行。
②另外，为适应特殊需求，可直接对系统进行修改，无需召集计算机编程专家。
7.3 CAE
计算机辅助工程能让几个应用程序共享数据库的信息，从而简化了数据库的生成过程。这些应用程序包括如(a) 结构和载荷成分的应力、应变、偏移及温度分布的有限元分析；(b) 数控数据的生成、储存和取回；(c) 集成电路和其它电子设备的设计。
随着计算机硬件和软件技术的日益成熟，制造过程和系统的计算机仿真方面增长迅速。过程模拟需要两种基本形式：（a）一个形式行动目的是确定其活力或优化或改善其性能；（b）这模型的多个过程和它们之间的相互作用，帮助工艺人员和工厂的设计人员在描述机械和设施布局。
每个过程使用了不同的数学方法建模。有限元分析已经越来越多地应用于市售廉价的软件包（模拟）。典型的问题的解决需要工艺的可行性（如金属板材在一特定的模成形），和工艺优化（例如，物料流在一个给定的模锻件，以确定潜在的缺损，或在铸造模具的设计，以消除热点，促进均匀冷却，并尽量减少缺陷）。
一个完整的制造系统涉及多个工艺及设备过程的模拟有助于工厂的工程师整理机器和识别关键机械元件。此外，这种模型可以协助制造工程师与调度和路由选择（通过离散事件系统仿真）。商用软件包经常用于这种模拟仿真。
聚合物加工，在其大多一般的情况下，涉及将固体（或液体）形态的任意形式的聚合性树脂（粉状、丸状、颗粒）转变为具体形状，尺寸和性能和属性的固体塑料产品。最终产品的性能与微结构紧密相关。因此，加工和产品质量的控制必须基于树脂性能、设备设计、操作条件、热机械过程、微结构和最终产品性能之间相互作用的理解。数学模型和计算机被同时用于获得这些相互作用的理解。鉴于进一步利用计算机辅助工程（CAE）在系统协同塑料加工。
7.3.1 MPI的介绍
MPI，作为一个模拟软件Moldflow公司，是一家集塑料成型过程的集成CAE模拟，包括MPI /流量分析，MPI /共注射，MPI /气体分析，MPI /优化分析，MPI /微孔分析，MPI /收缩分析，MPI /冷却分析，MPI /偏差分析，MPI /应力分析。MPI提供了在设计和制造全过程的解决方案，以提高生产率和提高零件质量。MPI的主要功能包括：
（1）独特的融合技术。MPI /融合可以直接分析薄壁零件的CAD实体模型，使模型的制备时间显著减少。节省时间，让你更多的分析设计迭代以及进行更加深入的分析。
（2）强大的工作流程和生产力工具。在MPI人性化的环境中，采用可视化和项目管理工具可以进行广泛的分析与优化设计。分析完成之后，可以随时迅速和容易地生成详细的网络
设计报告。
（3）适用于各种类型的解决方案。Moldflow的分析产品可以模拟塑料流动和包装，模具冷却，
热塑性塑料注塑件收缩与翘曲，气体辅助注射成型，共注射成型和注射压缩成型工艺。另外模拟注塑成型过程，包括热固性橡胶注射成型，反应注射成型（RIM），结构反应注射成型（SRIM），树脂传递模塑成型，微芯片封装和底部填充封装（倒装）。
（4）世界上最好的3D解决方案。使用经过被验证的有着基本解决方案技术的有限元网格体，MPI /三维可以在执行真正的三维流动模拟的部分时，自然的流向那些非常厚实和已经从薄到厚的极端变化的实体四面体。
（5）广泛支持几何类型。Moldflow的MPI技术可以用于所有的CAD模型的几何类型，包括传统的平面模型，线框、曲面模型，薄壁固体和厚或难平面固体。不管你的几何设计如何，你的模型可以在一个易于使用的，一致的，集成的环境完成仿真。
（6）独一的网络计算选择。优化制品和模具设计（MPI）已经在网络计算环境下开发的思想。例如，用户可以运行MPI /协同，前和后处理器，用户友好的Windows电脑而强大的UNIX 工作站上运行分析求解。用户还可以在任何特定时间，利用分布式计算环境在MPI和分配到任何网络计算机上进行分析。
英文原文
6.4 Automation of Manufacturing
6.4.1 Introduction
Automation is the technology by which a process or procedure is accomplished without human
assistance. It is implemented by using a program of instructions combined with a control system
that executes the instructions. To automate a process, power is required, both to drive the process
itself and to operate the program and control system. Although automation can be applied in a wide
variety of areas, it is most closely associated with the manufacturing industries. It was in the
context of manufacturing that the term was originally coined by an engineering manager at Ford
Motor Company in 1946 to describe the variety of automatic transfer devices and feed mechanisms
that had been installed in Ford’s production plants. It is ironic that nearly all modern applications of
automation are controlled by computer technologies that were not available in 1946.
Automated manufacturing systems operate in the factory on the physical product. They perform operations such as processing, assembly, inspection, or material handling, in some cases
accomplishing more than one of these operations in the same system. They are called automated
because they perform their operations with a reduced level of human participation compared with
the corresponding manual process. In some highly automated systems, there is virtually no human
participation. Examples of automated manufacturing systems include:
(1) Automated machine tools that process parts;
(2) Transfer lines that perform a series of machining operations;
(3) Manufacturing systems that use industrial robots to perform processing or assembly
operations;
(4) Automatic material handing and storage systems to integrate manufacturing operations;
(5) Automatic inspection systems for quality control.
Automated manufacturing systems can be classified into three basic types: (1) fixed
automation, (2) programmable automation, and (3) flexible automation.
Fixed automation is a system in which the sequence of processing (or assembly) operations is
fixed by the equipment configuration. Each of the operations in the sequence is usually simple,
involving perhaps a plain linear or rotating motion or an uncomplicated combination of the two. It
is the integration and coordination of many such operations into one piece of equipment that makes
the system complex. Typical features of fixed automation are:
(1) High initial investment for custom-engineered equipment;
(2) High productivity rates;
(3) Relatively inflexible in accommodating product variety.
The economic justification for fixed automation is found in products that are produced in very large quantities and at high production rates. The high initial cost is its character compared with alternative methods of production. Examples of fixed automation include machine transfer lines and automated assembly machines.
In programmable automation, the production equipment is designed with the capability to
change the sequence of operations to accommodate different product configurations. The operation
sequence is controlled with a program, which is a set of instructions coded so that they can be read
and interrupted by the system. New programs can be prepared and entered into the equipment to
produce new products. Programmable automated production systems are used in low- and
medium-volume production. The parts or products are typically made in batches. To produce each
new batch of a different product, the system must be reprogrammed with the set of machine instructions that correspond to the new product. The physical setup of machine must also be changed: tools must be loaded, fixtures must be attached to the machine table, and the required machine settings must be entered. Examples of programmable automation include numerically controlled machine tools, industrial robots, and programmable logic controllers.
Flexible automation is an extension of programmable automation. A flexible automated system is capable of producing a variety of parts (or products) with virtually no time lost for changeovers from one part style to the next. There is no lost production time while reprogramming the system and altering the physical setup (tooling, fixtures, machine settings). Consequently, the system can produce various combinations and schedules of part or products instead of requiring that they be made in batches. What makes flexible automation possible is that the differences between parts processed by the system are not significant. It is a case of soft variety, so that the amount of changeover required between styles is minimal. Examples of flexible automation are flexible manufacturing systems for performing machining operations that date back to the late 1960s.
6.4.2 Flexible Manufacturing System
In the modern manufacturing setting, flexibility is an important characteristic. It means that a manufacturing system is versatile and adaptable, while also capable of handling relatively high production runs. A flexible manufacturing system is versatile in that it can produce a variety of parts. It is adaptable because it can be quickly modified to produce a completely different line of parts.
A flexible manufacturing system (FMS) is a highly automated TG (group technology) machine cell, consisting of
a group of processing workstations (usually CNC machine tools), interconnected by an automated material
handing and storage system, and controlled by a distributed computer system. The reason the FMS
is called flexible is that it is capable of processing a variety of different part styles simultaneously at the various workstations, and the mix of patterns. The FMS is most suited for the mid-variety, mid-volume production range.
An FMS relies on the principles of group technology. Group technology is a manufacturing philosophy in which similar parts are identified and grouped together to take advantage of their similarities in design and production, similar parts are arranged into part families, where each part family possesses similar design and manufacturing characteristics. No manufacturing system can be completely flexible. There are limits to the range of parts or productions that can be made in an FMS. Accordingly, an FMS is designed to produce parts (or products) within a defined range of styles, sizes, and processes. In other words, an FMS is capable of producing a single part family or a limited range of part families.
An FMS must possess three capabilities: (1) the ability to identify and distinguish among the different part or product styles processed by the system, (2) quick changeover of operating instructions, and (3) quick changeover of physical setup.
6.4.3 Computer Integrated Manufacturing System
Computer integrated manufacturing (CIM) is the term used to describe the modern approach to manufacturing. Although CIM encompasses many of the other advanced manufacturing technologies such as computer numerical control (CNC), computer-aided design/computer-aided manufacturing (CAD/CAM), robotics, and just-in-time delivery (JIT), it is more than a new technology or a new concept. Computer integrated manufacturing is an entirely new approach to manufacturing, a new way of doing business.
To understand CIM, it is necessary to begin with a comparison of modern and traditional manufacturing. Modern manufacturing encompasses all of the activities and processes necessary to convert raw materials into finished products, deliver them to the market, and support them in the field. These activities include the following:
(1) Identifying a need for a product;
(2) Designing a product to meet the needs;
(3) Obtaining the raw materials needed to produce the product;
(4) Applying appropriate processes to transform the raw materials into finished products;
(5) Transporting product to the market;
(6) Marinating the product to ensure proper performance in the field.
This broad, modern view of manufacturing can be compared with the more limited traditional view that focused almost entirely on the conversion processes. The old approach excluded such critical pre-conversion elements as market analysis research, development, and design, as well as such after-conversion elements as product delivery and product maintenance. In other words, in the old approach to manufacturing, only those processes that took place on the
shop floor were considered manufacturing. This traditional approach of separating the overall concept into numerous stand-alone specialized elements was not fundamentally changed with the advent of automation.
With CIM, not only are the various elements automated, but also the islands of automation are all linked together or integrated. Integration means that a system can provide complete and instantaneous sharing of information. In modern manufacturing, Integration is accomplished by computers. CIM, then, is the total integration of all components involved in converting raw materials into finished products and getting the products to the market.
Chapter 7
CAD/CAM/CAE
7.1 The Computer in Die Design
The term CAD is alternately used to mean computer aided design and computer aided drafting. Actually it can mean either one or both of these concepts, and the tool designer will have occasion to use it in both forms.
CAD computer aided design means using the computer and peripheral devices to simplify and enhance the design process. CAD computer aided drafting means using the computer and peripheral devices to produce the documentation and graphics for the design process. This
documentation usually includes such things as preliminary drawings, working drawings, parts lists, and design calculations.
A CAD system, whether taken to mean computer aided design system or computer aided drafting system, consists of three basic components: (1) hardware, (2) software, and (3) users. The hardware components of a typical CAD system include a processor, a system display, a keyboard, a digitizer, and a plotter. The software component of a CAD system consists of the programs which allow it to perform design and drafting functions. The user is the tool designer who uses the hardware and software to simplify and enhance the design process.
The broad-based emergence of CAD on an industry-wide basis did not begin to materialize until the 1980’s. However, CAD as a concept is not new. Althoug h it has changed drastically over the years, CAD had its beginnings almost thirty years ago during the middle 1950’s. Some of the first computers included graphics displays. Now a graphics display is an integral part of every CAD system.
Graphics displays represented the first real step toward bringing the worlds of tool design and the computer together. The plotters depicted in figure, represented the next step. With the advent of the digitizing tablet in the early 1960’s, CAD hardware as we know it today began to take shape. The development of computer graphics software followed soon after these hardware developments. Early CAD systems were large, cumbersome, and expensive. So expensive, in fact, that
only the largest companies could afford them. During the late 1950’s and early 1960’s, CAD was looked on as an interesting, but impractical novelty that had only limited potential in tool design applications. However, with the introduction of the silicon chip during the 1970’s, computers began to take their place in the world of tool design.
Integrated circuits on silicon chips allowed full scale computers to be packaged in small consoles no larger than television sets. These “mini-computers” had all of the characteristics of full scale computers, but they were smaller and considerably less expensive. Even smaller computers
called microcomputers followed soon after.
The 1970’s saw continued advances in CAD hardware and software technology. So much so that by the beginning of the 1980’s, making and marketing CAD systems had become a growth industry. Also, CAD has been transformed from its status of impractical novelty to its new status as one of the most important inventions to date. By 1980, numerous CAD systems were available ranging in sizes from microcomputer systems to large minicomputer and mainframe systems.
7.2 CAD/CAM
7.2.1 CAD
Computer-aided design/computer-aided manufacturing (CAD/CAM) refers to the integration of computers into the design and production process to improve productivity. The heart of the CAD/CAM system is the design terminal and related hardware, such as computer, printer, plotter, paper tape punch, a tape reader, and digitizer. The design is constantly monitored on the terminal until it is completed. A hard copy can be generated if necessary. A computer tape or other control medium containing the design data guides computer-controlled machine tools during the manufacturing, testing, and quality control.
The software for CAD/CAM is a collection of computer programs stored in the system to make the various hardware components perform specific tasks. Examples of software are programs developed to generate a NC tool path, to assemble a bill of materials, or to create nodes and elements on a finite element model. Some of these software packages are referred to as software modules and can be classified into four categories: (1) operating systems, (2) general-purpose programs, (3) application programs, and (4) user programs. Although there are other kinds of software, these are sufficient for an explanation of the complexities in developing a CAD/CAM system.
Operating systems are programs written for a specific computer or class of computers. For convenient and efficient operation, programs and data are available in the system’s memory. The operating system is especially concerned with the input/output (I/O) devices like displays, printers, and tape punches. In most cases the operating system is supplied with the computer.
Although it may be argued that there are no general-purpose programs as such, some are more general than others. An example is a graphics program written in a high-level language like FORTRAN that allows the generation of geometric entities such as lines, circles, and parabolas and a combination of these to make designs. These designs may range from printed circuits to drill jigs and fixtures.
Application programs are developed for a special or specific purpose. The first language for specialized application was Automatically Programmed Tools (APT) in 1956. APT was deve- loped to ease the job of NC programmers in developing input to NC machine tools, as illustrated in Fig. 7-1. Other examples of application programs, relative to CAD/CAM, are programs developed specifically for the generation of finite element mesh and flat pattern development or “unbending” of sheet metal parts. These programs are usually purchased with the system or from
a software supplier
User programs in CAD/CAM are highly specialized packages for creating specific outputs. For example, a user program may automatically design a gear after the user inputs certain parameters like the number of teeth, pitch diameter, and so on. Another program may calculate optimum feeds and speeds, given cutter information, material, depth of cut, and so on. These programs are often developed by the user from a software module furnished by the supplier of
general-purpose software. Not all CAD/CAM software packages have these user programs, even though considerable savings can be achieved with them.
1. Computer Graphics
The computer graphics system accumulates and stores physically related data identifying the precise location, dimensions descriptive text, and other properties of every design element. The design-related data help the user-operator perform complex engineering analysis, generate bills of materials, produce reports, and detect design inconsistencies before the part reaches manufacturing.
With computer graphics two-dimensional drawings can be made into three-dimensional wire frames and solid models.
2. Wire Frames
The simple wire frame plot is the least expensive form of geometrically displaying a model. It is useful to verify the basic properties of a shape and continuity of the model. However, when a complex model is developed, wire frame displays become inadequate. Solid models eliminate most of the problems of the wire frame.
3. Solid Modeling
There are three basic techniques for generating solid models: constructive solid geometry (CSG), boundary representation (B-Rep), and analytical solid modeling.
In the CSG approach, various geometric patterns such as cylinders, spheres, and cones are combined by Boolean algebra to create designs.
In the B-Rep method, a profile of the part is defined and then swept, either linearly or radially, and the enclosed area represents the solid form.
4. Analytical Method
This method is similar to the B-Rep but enhances the creation of finite element model during generation of the design. Commercial packages do not use strictly one method or another. As an example, CSG packages may use B-Rep techniques to generate initial patterns, while B-Rep or analytical packages may use Boolean algebra to subtract patterns, such as cylinders or cones, from a design to create a hole in the design.
7.2.2 CAM
Computer-aided manufacture (CAM) centers around four main areas: NC, process planning, robotics, and factory management.
1. Numerical Control
The importance of NC in the CAM area is that the computer can generate a NC program directly from a geometric model or part. At present, automatic capabilities are generally limited to highly symmetric geometries and other specialized parts. However, in the near future some companies will not use drawings at all, but will be passing part information directly from design to manufacturing via a data base. As the drawings disappear, so will many of the problems, since computer models developed from a common integrated database will be used by both design and manufacturing. This can be done even though the departments may be widely separated geographically, because in essence they will be no farther apart than the terminals on their respective desks.
2. Process Planning
Process planning involves the detailed planning of the production sequence from start to finish. What is relevant to CAM is a process planning system that is able to produce process plans directly from the geometric model database with almost no human assistance.
3. Robots
Many advances are being made to integrate robots into the manufacturing system, as in on-line assembly, welding, and painting.
4. Factory Management
Factory management uses interactive factory data collection to get timely information from the factory floor. At the same time, it uses this data to calculate production priorities and dynamically determine what work needs to be done next to ensure that the master production schedule is being properly executed. The system can also be directly modified to satisfy a specific need without calling in computer programming experts.
7.3 CAE
Computer-aided engineering simplifies the creation of the database, by allowing several applications to share the information in the database. These applications include, for example, (a) finite-element analysis of stresses, strains, deflections, and temperature distribution in structures and load-bearing members, (b) the generation, storage, and retrieval of NC data, and (c) the design of integrated circuits and other electronic devices.
With the increasing sophistication of computer hardware and software, one area which has grown rapidly is computer simulation of manufacturing processes and systems. Process simulation takes two basic forms: (a) it is a model of a specific operation intended to determine the viability of a process or to optimize or improve its performance; (b) it models multiple processes and their interactions, and it helps process planners and plant designers in the layout of machinery and facilities.
Individual processes have been modeled using various mathematical schemes. Finite-element analysis has been increasingly applied in software packages (process simulation) that are commercially available and inexpensive. Typical problems addressed are process viability (such as the formability of sheet metal in a certain die), and process optimization (for example, the material flow in forging in a given die, to identify potential defects, or mold design in casting, to eliminate hot spots, to promote uniform cooling, and to minimize defects).
Simulation of an entire manufacturing system involving multiple processes and equipment helps plant engineers to organize machinery and to identify critical machinery elements. In addition, such models can assist manufacturing engineers with scheduling and routing (by discrete event simulation). Commercially available software packages are often used for these simulations. Polymer processing, in its most general context, involves the transformation of a solid (sometimes liquid) polymeric resin, which is in a random form (e.g. powder, pellets, beads), to a solid plastics product of specified shape, dimensions, and properties. The ultimate properties of the article are closely related to the microstructure. Therefore, the control of the process and product quality must be based on an understanding of the interactions between resin properties, equipment design,
operating conditions, thermo-mechanics history, microstructure, and ultimate product properties.
Mathematical modeling and computer simulation have been employed to obtain an understanding of these interactions. Such an approach has gained more importance in view of the expanding
utilization of computer aided engineering (CAE) systems in conjunction
with plastics processing.
7.3.1 MPI Introduction
MPI, as one of simulation software of MOLDFLOW corporation, is a set of integrated CAE simulations for plastics molding process, including MPI/Flow analysis, MPI/Co-Injection analysis, MPI/Gas analysis, MPI/Optim analysis, MPI/Microcellular analysis, MPI/Shrink analysis, MPI/Cool analysis, MPI/Warp analysis, MPI/Stress analysis. MPI provides solution in all stages of design and manufacturing, to improve productivity and enhance part quality. Key features of MPI include:
(1) Unique, patented fusion technology. MPI/Fusion allows you to analyze CAD solid models of thin-walled parts directly, resulting in a significant decrease in model preparation time. The timesaving allow you to analyze more design iterations as well as perform more in-depth analyses.
(2) Powerful workflow and productivity tools. The user-friendly environments in MPI employ visualization and project management tools that allow you to undertake extensive design analysis and optimization. After your analyses are complete, you can produce detailed, web-ready design reports quickly and easily.
(3) Proven solutions for all types of applications. Moldflow’s analysis products can simulate plastics flow and packing, mold cooling, and part shrinkage and warpage for thermoplastic injection molding, gas-assisted injection molding, co-injection molding and injection- compression molding processes. Additional modules simulate reactive molding processes including thermoset and rubber injection molding, reaction injection molding (RIM), structural reaction injection molding (SRIM), resin transfer molding, microchip encapsulation and underfill (flip-chip)
缸体机械加工工艺设计 发动机缸体是发动机零件中结构较为复杂的箱体零件，其精度要求高，加工工艺复杂，并且加工加工质量的好坏直接影响发动机整个机构的性能，因此，它成为各个发动机生产厂家所关注的重点零件之一。 1.发动机缸体的工艺特点 缸体为一整体铸造结构，其上部有4个缸套安装孔；缸体的水平隔板将缸体分成上下两部分；缸体的前端面从到后排列有三个同轴线的凸轮轴安装孔和惰轮轴孔。 缸体的工艺特点是：结构、形状复杂；加工的平面和孔比较多；壁厚不均，刚度低；加工精度要求高，属于典型的箱体类加工零件。缸体的主要加工表面有顶面、主轴承侧面、缸孔、主轴承孔及凸轮轴孔等，它们的加工精度将直接影响发动机的装配精度和工作性能，主要依靠设备进度、工夹具的可靠性和加工工艺的合理性来保证。 2. 发动机缸体工艺方案设计原则和依据 设计工艺方案应在保证产品质量的同时，充分考虑生产周期、成本和环境保护；根据本企业能力，积极采用国内外先进的工艺技术和装备，不断提高企业工艺水平。发动机缸体机械加工工艺设计应遵循以下基本原则： （1）加工设备选型原则加工设备选型采用刚柔结合的原则，加工设备以卧式加工中心为主，少量采用立式加工中心，关键工序—曲轴孔、缸孔、平衡轴孔加工采用高精度高速卧式加工中心，非关键工序—上下前后四个平面的粗铣采用高效并有一定调整范围的专用机床加工； （2）集中工序原则关键工序—曲轴孔、缸孔、平衡轴孔的精加工缸盖结合面的精铣，采用在集中在一道工序一次装夹完成全部加工内容方案，以确保产品精度满足缸体关键品质的工艺性能和有关技术要求。 根据汽车发动机缸体的工艺特点和生产任务要求，发动机缸体机械加工自动生产线由卧式加工中心CWK500和CWK500D加工中心、专用铣/镗床、立式加工中心matec-30L等设备组成。 （1）顶底面及瓦盖止口面粗铣组合机床本机床为双面卧式专用铣床，采用移动工作台带动工件，机床采用进口西门子S7-200PLC系统控制，机床设独立电控柜，切削过程自动化完成，有自动和调整两种状态； （2）高速卧式加工中心CWK500 该加工中心可实现最大流量的湿加工，但由于设备自动排屑处理系统是通过位于托盘下的内置宽式排屑器而完成，该加工中心可以进行干加工；机床主轴转速6000r/min，快速进给速度38m/min； （3）前后端面粗铣组合机床机床采用液压传动；控制系统采用进口西门子S7-200PLC系统控制，机床具有一定的柔性； （4）采用机床TXK1500 本机床有立式加工中心改造而成形，具备立式加工中心的特点及性能，该机床具有高精度、高强度、高耐磨度、高稳定性、高配置等优点； （5）高速立式加工中心matec-30L 该加工中心主轴最高转速9000 r/min。控制系统采用西门子公司SINUMERIK840D控制系统 （6）高速卧式加工中心CWK500D 主轴最高转速15000 r/min。 3. 发动机缸体机械加工工艺设计的主要内容 发动机缸体结构复杂，精度要求高，尺寸较大，是薄壁零件，有若干精度要
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）
I / 11 本科毕业设计外文翻译 <2018届） 论文题目基于WEB 的J2EE 的信息系统的方法研究 作者姓名[单击此处输入姓名] 指导教师[单击此处输入姓名] 学科(专业 > 所在学院计算机科学与技术学院 提交日期[时间 ]
基于WEB的J2EE的信息系统的方法研究 摘要：本文介绍基于工程的Java开发框架背后的概念，并介绍它如何用于IT 工程开发。因为有许多相同设计和开发工作在不同的方式下重复，而且并不总是符合最佳实践，所以许多开发框架建立了。我们已经定义了共同关注的问题和应用模式，代表有效解决办法的工具。开发框架提供：<1）从用户界面到数据集成的应用程序开发堆栈；<2）一个架构，基本环境及他们的相关技术，这些技术用来使用其他一些框架。架构定义了一个开发方法，其目的是协助客户开发工程。 关键词：J2EE 框架WEB开发 一、引言 软件工具包用来进行复杂的空间动态系统的非线性分析越来越多地使用基于Web的网络平台，以实现他们的用户界面，科学分析，分布仿真结果和科学家之间的信息交流。对于许多应用系统基于Web访问的非线性分析模拟软件成为一个重要组成部分。网络硬件和软件方面的密集技术变革[1]提供了比过去更多的自由选择机会[2]。因此，WEB平台的合理选择和发展对整个地区的非线性分析及其众多的应用程序具有越来越重要的意义。现阶段的WEB发展的特点是出现了大量的开源框架。框架将Web开发提到一个更高的水平，使基本功能的重复使用成为可能和从而提高了开发的生产力。 在某些情况下，开源框架没有提供常见问题的一个解决方案。出于这个原因，开发在开源框架的基础上建立自己的工程发展框架。本文旨在描述是一个基于Java的框架，该框架利用了开源框架并有助于开发基于Web的应用。通过分析现有的开源框架，本文提出了新的架构，基本环境及他们用来提高和利用其他一些框架的相关技术。架构定义了自己开发方法，其目的是协助客户开发和事例工程。 应用程序设计应该关注在工程中的重复利用。即使有独特的功能要求，也
土木工程毕业设计外文文献翻译修订版 IBMT standardization office【IBMT5AB-IBMT08-IBMT2C-ZZT18】
外文文献翻译 Reinforced Concrete （来自《土木工程英语》） Concrete and reinforced concrete are used as building materials in every country. In many, including the United States and Canada, reinforced concrete is a dominant structural material in engineered construction. The universal nature of reinforced concrete construction stems from the wide availability of reinforcing bars and the constituents of concrete, gravel, sand, and cement, the relatively simple skills required in concrete construction, and the economy of reinforced concrete compared to other forms of construction. Concrete and reinforced concrete are used in bridges, buildings of all sorts underground structures, water tanks, television towers, offshore oil exploration and production structures, dams, and even in ships. Reinforced concrete structures may be cast-in-place concrete, constructed in their final location, or they may be precast concrete produced in a factory and erected at the construction site. Concrete structures may be severe and functional in design, or the shape and layout and be whimsical and artistic. Few other building materials off the architect and engineer such versatility and scope. Concrete is strong in compression but weak in tension. As a result, cracks develop whenever loads, or restrained shrinkage of temperature changes, give rise to tensile stresses in excess of the tensile strength of the concrete. In
机械设计 摘要：机器是由机械装置和其它组件组成的。它是一种用来转换或传递能量的装置，例如：发动机、涡轮机、车辆、起重机、印刷机、洗衣机、照相机和摄影机等。许多原则和设计方法不但适用于机器的设计，也适用于非机器的设计。术语中的“机械装置设计”的含义要比“机械设计”的含义更为广泛一些，机械装置设计包括机械设计。在分析运动及设计结构时，要把产品外型以及以后的保养也要考虑在机械设计中。在机械工程领域中，以及其它工程领域中，所有这些都需要机械设备，比如：开关、凸轮、阀门、船舶以及搅拌机等。 关键词：设计流程设计规则机械设计 设计流程 设计开始之前就要想到机器的实际性，现存的机器需要在耐用性、效率、重量、速度，或者成本上得到改善。新的机器必需具有以前机器所能执行的功能。 在设计的初始阶段，应该允许设计人员充分发挥创造性，不要受到任何约束。即使产生了许多不切实际的想法，也会在设计的早期，即在绘制图纸之前被改正掉。只有这样，才不致于阻断创新的思路。通常,还要提出几套设计方案，然后加以比较。很有可能在这个计划最后决定中,使用了某些不在计划之内的一些设想。 一般的当外型特点和组件部分的尺寸特点分析得透彻时，就可以全面的设计和分析。接着还要客观的分析机器性能的优越性，以及它的安全、重量、耐用性，并且竞争力的成本也要考虑在分析结果之内。每一个至关重要的部分要优化它的比例和尺寸，同时也要保持与其它组成部分相协调。 也要选择原材料和处理原材料的方法。通过力学原理来分析和实现这些重要的特性，如那些静态反应的能量和摩擦力的最佳利用，像动力惯性、加速动力和能量；包括弹性材料的强度、应力和刚度等材料的物理特性，以及流体润滑和驱动器的流体力学。设计的过程是重复和合作的过程，无论是正式或非正式的进行，对设计者来说每个阶段都很重要。 最后，以图样为设计的标准，并建立将来的模型。如果它的测试是符合事先要
机械类毕业设计外文翻译
外文原文 Options for micro-holemaking As in the macroscale-machining world, holemaking is one of the most— if not the most—frequently performed operations for micromachining. Many options exist for how those holes are created. Each has its advantages and limitations, depending on the required hole diameter and depth, workpiece material and equipment requirements. This article covers holemaking with through-coolant drills and those without coolant holes, plunge milling, microdrilling using sinker EDMs and laser drilling. Helpful Holes Getting coolant to the drill tip while the tool is cutting helps reduce the amount of heat at the tool/workpiece interface and evacuate chips regardless of hole diameter. But through-coolant capability is especially helpful when deep-hole microdrilling because the tools are delicate and prone to failure when experiencing recutting of chips, chip packing and too much exposure to carbide’s worst enemy—heat. When applying flood coolant, the drill itself blocks access to the cutting action. “Somewhere about 3 to 5 diam eters deep, the coolant has trouble getting down to the tip,” said Jeff Davis, vice president of engineering for Harvey Tool Co., Rowley, Mass. “It becomes wise to use a coolant-fed drill at that point.” In addition, flood coolant can cause more harm than good when microholemaking. “The pressure from the flood coolant can sometimes snap fragile drills as they enter the part,” Davis said. The toolmaker offers a line of through-coolant drills with diameters from 0.039" to 0.125" that are able to produce holes up to 12 diameters deep, as well as microdrills without coolant holes from 0.002" to 0.020". Having through-coolant capacity isn’t enough, though. Coolant needs to flow at a rate that enables it to clear the chips out of the hole. Davis recommends, at a minimum, 600 to 800 psi of coolant pressure. “It works much better if you have higher pressure than that,” he added. To prevent those tiny coolant holes from becoming clogged with debris, Davis also recommends a 5μm or finer coolant filter. Another recommendation is to machine a pilot, or guide, hole to prevent the tool from wandering on top of the workpiece and aid in producing a straight hole. When applying a pilot drill, it’s important to select one with an included angle on its point that’s equal t o or larger than the included angle on the through-coolant drill that follows.
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。
Section 3 Design philosophy, design method and earth pressures 3.1 Design philosophy 3.1.1 General The design of earth retaining structures requires consideration of the interaction between the ground and the structure. It requires the performance of two sets of calculations: 1）a set of equilibrium calculations to determine the overall proportions and the geometry of the structure necessary to achieve equilibrium under the relevant earth pressures and forces; 2）structural design calculations to determine the size and properties of thestructural sections necessary to resist the bending moments and shear forces determined from the equilibrium calculations. Both sets of calculations are carried out for specific design situations (see 3.2.2) in accordance with the principles of limit state design. The selected design situations should be sufficiently Severe and varied so as to encompass all reasonable conditions which can be foreseen during the period of construction and the life of the retaining wall. 3.1.2 Limit state design This code of practice adopts the philosophy of limit state design. This philosophy does not impose upon the designer any special requirements as to the manner in which the safety and stability of the retaining wall may be achieved, whether by overall factors of safety, or partial factors of safety, or by other measures. Limit states (see 1.3.13) are classified into: a) ultimate limit states (see 3.1.3); b) serviceability limit states (see 3.1.4). Typical ultimate limit states are depicted in figure 3. Rupture states which are reached before collapse occurs are, for simplicity, also classified and
毕业设计（论文） 外文文献译文及原文 学生：李树森 学号：201006090217 院（系）：电气与信息工程学院 专业：网络工程 指导教师：王立梅 2014年06月10日
JSP的技术发展历史 作者：Kathy Sierra and Bert Bates 来源：Servlet&JSP Java Server Pages(JSP)是一种基于web的脚本编程技术，类似于网景公司的服务器端Java脚本语言—— server-side JavaScript(SSJS)和微软的Active Server Pages(ASP)。与SSJS和ASP相比，JSP具有更好的可扩展性，并且它不专属于任何一家厂商或某一特定的Web服务器。尽管JSP规范是由Sun 公司制定的，但任何厂商都可以在自己的系统上实现JSP。 在Sun正式发布JSP之后，这种新的Web应用开发技术很快引起了人们的关注。JSP为创建高度动态的Web应用提供了一个独特的开发环境。按照Sun的说法，JSP能够适应市场上包括Apache WebServer、IIS4.0在内的85%的服务器产品。 本文将介绍JSP相关的知识，以及JavaBean的相关内容，当然都是比较粗略的介绍其中的基本内容，仅仅起到抛砖引玉的作用，如果读者需要更详细的信息，请参考相应的JSP的书籍。 1.1 概述 JSP(Java Server Pages)是由Sun Microsystems公司倡导、许多公司参与一起建立的一种动态网页技术标准，其在动态网页的建设中有其强大而特别的功能。JSP与Microsoft的ASP技术非常相似。两者都提供在HTML代码中混合某种程序代码、由语言引擎解释执行程序代码的能力。下面我们简单的对它进行介绍。 JSP页面最终会转换成servlet。因而，从根本上，JSP页面能够执行的任何任务都可以用servlet 来完成。然而，这种底层的等同性并不意味着servlet和JSP页面对于所有的情况都等同适用。问题不在于技术的能力，而是二者在便利性、生产率和可维护性上的不同。毕竟，在特定平台上能够用Java 编程语言完成的事情，同样可以用汇编语言来完成，但是选择哪种语言依旧十分重要。 和单独使用servlet相比，JSP提供下述好处： JSP中HTML的编写与维护更为简单。JSP中可以使用常规的HTML：没有额外的反斜杠，没有额外的双引号，也没有暗含的Java语法。 能够使用标准的网站开发工具。即使是那些对JSP一无所知的HTML工具，我们也可以使用，因为它们会忽略JSP标签。 可以对开发团队进行划分。Java程序员可以致力于动态代码。Web开发人员可以将经理集中在表示层上。对于大型的项目，这种划分极为重要。依据开发团队的大小，及项目的复杂程度，可以对静态HTML和动态内容进行弱分离和强分离。 此处的讨论并不是说人们应该放弃使用servlet而仅仅使用JSP。事实上，几乎所有的项目都会同时用到这两种技术。在某些项目中，更适宜选用servlet，而针对项目中的某些请求，我们可能会在MVC构架下组合使用这两项技术。我们总是希望用适当的工具完成相对应的工作，仅仅是servlet并不一定能够胜任所有工作。 1.2 JSP的由来 Sun公司的JSP技术，使Web页面开发人员可以使用HTML或者XML标识来设计和格式化最终
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（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.doczj.com/doc/a23310406.html,，niuzhiguo@https://www.doczj.com/doc/a23310406.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.doczj.com/doc/a23310406.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。
本科生毕业设计（论文）外文科技文献译文 译文题目(外文题目)学院(系)Socket网络编程的设计与实现A Design and Implementation of Active Network Socket Programming 机械与能源工程学院 专学业 号 机械设计制造及其自动化 071895 学生姓名李杰林 日期2012年5月27日指导教师签名日期
摘要：编程节点和活跃网络的概念将可编程性引入到通信网络中，并且代码和数据可以在发送过程中进行修改。最近，多个研究小组已经设计和实现了自己的设计平台。每个设计都有其自己的优点和缺点，但是在不同平台之间都存在着互操作性问题。因此，我们引入一个类似网络socket编程的概念。我们建立一组针对应用程序进行编程的简单接口，这组被称为活跃网络Socket编程（ANSP）的接口，将在所有执行环境下工作。因此，ANSP 提供一个类似于“一次性编写，无限制运行”的开放编程模型，它可以工作在所有的可执行环境下。它解决了活跃网络中的异构性，当应用程序需要访问异构网络内的所有地区，在临界点部署特殊服务或监视整个网络的性能时显得相当重要。我们的方案是在现有的环境中，所有应用程序可以很容易地安装上一个薄薄的透明层而不是引入一个新的平台。 关键词：活跃网络；应用程序编程接口；活跃网络socket编程
1 导言 1990年，为了在互联网上引入新的网络协议，克拉克和藤农豪斯[1]提出了一种新的设 计框架。自公布这一标志性文件，活跃网络设计框架[2，3，10]已经慢慢在20世纪90 年代末成形。活跃网络允许程序代码和数据可以同时在互联网上提供积极的网络范式，此外，他们可以在传送到目的地的过程中得到执行和修改。ABone作为一个全球性的骨干网络，开 始进行活跃网络实验。除执行平台的不成熟，商业上活跃网络在互联网上的部署也成为主要障碍。例如，一个供应商可能不乐意让网络路由器运行一些可能影响其预期路由性能的未知程序，。因此，作为替代提出了允许活跃网络在互联网上运作的概念，如欧洲研究课题组提出的应用层活跃网络（ALAN）项目[4]。 在ALAN项目中，活跃服务器系统位于网络的不同地址，并且这些应用程序都可以运行在活跃系统的网络应用层上。另一个潜在的方法是网络服务提供商提供更优质的活跃网络服务类。这个服务类应该提供最优质的服务质量（QOS），并允许路由器对计算机的访问。通过这种方法，网络服务提供商可以创建一个新的收入来源。 对活跃网络的研究已取得稳步进展。由于活跃网络在互联网上推出了可编程性，相应 地应建立供应用程序工作的可执行平台。这些操作系统平台执行环境（EES），其中一些已 被创建，例如，活跃信号协议（ASP）[12]和活跃网络传输系统（ANTS）[11]。因此，不 同的应用程序可以实现对活跃网络概念的测试。 在这些EES 环境下，已经开展了一系列验证活跃网络概念的实验，例如，移动网络[5]，网页代理[6]，多播路由器[7]。活跃网络引进了很多在网络上兼有灵活性和可扩展性的方案。几个研究小组已经提出了各种可通过路由器进行网络计算的可执行环境。他们的成果和现有基础设施的潜在好处正在被评估[8，9]。不幸的是，他们很少关心互操作性问题，活跃网络由多个执行环境组成，例如，在ABone 中存在三个EES，专为一个EES编写的应用程序不能在其他平台上运行。这就出现了一种资源划分为不同运行环境的问题。此外，总是有一些关键的网络应用需要跨环境运行，如信息收集和关键点部署监测网络的服务。 在本文中，被称为活跃网络Socket编程（ANSP）的框架模型，可以在所有EES下运行。它提供了以下主要目标： ??通过单一编程接口编写应用程序。 由于ANSP提供的编程接口，使得EES的设计与ANSP 独立。这使得未来执行环境的发展和提高更加透明。
编号： 毕业设计(论文)外文翻译 （原文） 院（系）：应用科技学院 专业：机械设计制造及其自动化 学生姓名：邓瑜 学号：0501120501 指导教师单位：应用科技学院 姓名：黄小能 职称： 2009年 5 月20 日
The Injection Molding The Introduction of Molds The mold is at the core of a plastic manufacturing process because its cavity gives a part its shape. This makes the mold at least as critical-and many cases more so-for the quality of the end product as, for example, the plasticiting unit or other components of the processing equipment. Mold Material Depending on the processing parameters for the various processing methods as well as the length of the production run, the number of finished products to be produced, molds for plastics processing must satisfy a great variety of requirements. It is therefore not surprising that molds can be made from a very broad spectrum of materials, including-from a technical standpoint-such exotic materials as paper matched and plaster. However, because most processes require high pressures, often combined with high temperatures, metals still represent by far the most important material group, with steel being the predominant metal. It is interesting in this regard that, in many cases, the selection of the mold material is not only a question of material properties and an optimum price-to-performance ratio but also that the methods used to produce the mold, and thus the entire design, can be influenced. A typical example can be seen in the choice between cast metal molds, with their very different cooling systems, compared to machined molds. In addition, the production technique can also have an effect; for instance, it is often reported that, for the sake of simplicity, a prototype mold is frequently machined from solid stock with the aid of the latest technology such as computer-aided (CAD) and computer-integrated manufacturing (CIM). In contrast to the previously used methods based on the use of patterns, the use of CAD and CAM often represents the more economical solution today, not only because this production capability is available pin-house but also because with any other technique an order would have to be placed with an outside supplier. Overall, although high-grade materials are often used, as a rule standard materials are used in mold making. New, state-of-the art (high-performance) materials, such as ceramics, for instance, are almost completely absent. This may be related to the fact that their desirable characteristics, such as constant properties up to very high temperatures, are not required on molds, whereas their negative characteristics, e. g. low tensile strength and poor thermal conductivity, have a clearly related to ceramics, such as sintered material, is found in mild making only to a limited degree. This refers less to the modern materials and components