本科毕业生外文文献翻译
毕业论文(设计)外文文献翻译及原文
金融体制、融资约束与投资——来自OECD的实证分析R．SemenovDepartment of Economics，University of Nijmegen，Nijmegen（荷兰内梅亨大学，经济学院）这篇论文考查了OECD的11个国家中现金流量对企业投资的影响.我们发现不同国家之间投资对企业内部可获取资金的敏感性具有显著差异,并且银企之间具有明显的紧密关系的国家的敏感性比银企之间具有公平关系的国家的低.同时，我们发现融资约束与整体金融发展指标不存在关系.我们的结论与资本市场信息和激励问题对企业投资具有重要作用这种观点一致，并且紧密的银企关系会减少这些问题从而增加企业获取外部融资的渠道。
一、引言各个国家的企业在显著不同的金融体制下运行。
金融发展水平的差别(例如，相对GDP的信用额度和相对GDP的相应股票市场的资本化程度），在所有者和管理者关系、企业和债权人的模式中，企业控制的市场活动水平可以很好地被记录.在完美资本市场,对于具有正的净现值投资机会的企业将一直获得资金。
然而，经济理论表明市场摩擦，诸如信息不对称和激励问题会使获得外部资本更加昂贵，并且具有盈利投资机会的企业不一定能够获取所需资本.这表明融资要素，例如内部产生资金数量、新债务和权益的可得性，共同决定了企业的投资决策.现今已经有大量考查外部资金可得性对投资决策的影响的实证资料（可参考，例如Fazzari（1998）、 Hoshi(1991)、 Chapman（1996）、Samuel(1998））.大多数研究结果表明金融变量例如现金流量有助于解释企业的投资水平。
这项研究结果解释表明企业投资受限于外部资金的可得性。
很多模型强调运行正常的金融中介和金融市场有助于改善信息不对称和交易成本，减缓不对称问题,从而促使储蓄资金投着长期和高回报的项目,并且提高资源的有效配置（参看Levine（1997)的评论文章）。
因而我们预期用于更加发达的金融体制的国家的企业将更容易获得外部融资.几位学者已经指出建立企业和金融中介机构可进一步缓解金融市场摩擦。
文献翻译 译文+原文
09届本科毕业设计(论文)外文文献翻译学 院： 物理与电子工程学院专 业： 光电信息工程姓 名： 徐 驰学 号： Y05209222 外文出处： Surface & Coatings Technology214（2013）131-137附 件： 1.外文资料翻译译文；2.外文原文。
(用外文写)附件1：外文资料翻译译文气体温度通过PECVD沉积对Si：H薄膜的结构和光电性能的影响摘要气体温度的影响（TG）在等离子体增强化学气相沉积法（PECVD）生长的薄膜的结构和光电特性：H薄膜已使用多种表征技术研究。
气体的温度被确定为制备工艺的优化、结构和光电薄膜的性能改进的一个重要参数。
薄膜的结构性能进行了研究使用原子力显微镜（AFM），傅立叶变换红外光谱（FTIR），拉曼光谱，和电子自旋共振（ESR）。
此外，光谱椭偏仪（SE），在紫外线–可见光区域的光传输的测量和电气测量被用来研究的薄膜的光学和电学性能。
它被发现在Tg的变化可以修改的表面粗糙度，非晶网络秩序，氢键模式和薄膜的密度，并最终提高光学和电学性能。
1.介绍等离子体增强化学气相沉积法（PECVD）是氢化非晶硅薄膜制备一种技术，具有广泛的实际应用的重要材料。
它是用于太阳能电池生产，在夜视系统红外探测器，和薄膜晶体管的平板显示装置。
所有这些应用都是基于其良好的电气和光学特性以及与半导体技术兼容。
然而，根据a-Si的性质，PECVD制备H薄膜需要敏感的沉积条件，如衬底温度，功率密度，气体流量和压力。
许多努力已经花在制备高品质的薄膜具有较低的缺陷密度和较高的结构稳定性的H薄膜。
众所周知，衬底温度的强烈影响的自由基扩散的生长表面上，从而导致这些自由基更容易定位在最佳生长区。
因此，衬底温度一直是研究最多的沉积参数。
至于温度参数在PECVD工艺而言，除了衬底温度，气体温度（Tg）美联储在PECVD反应室在辉光放电是定制的a-Si的性能参数：H薄膜的新工艺。
浙江大学本科毕业论文外文文献翻译
核准通过，归档资料。
未经允许，请勿外传!浙江大学本科毕业论文外文文献翻译The influence of political connections on the firm value of small and medium-sized enterprises in China政治关联在中国对中小型企业价值的影响1摘要中小型企业的价值受很多因素的影响,比如股东、现金流以及政治关联等.这篇文章调查的正是在中国政治关联对中小型企业价值的影响。
通过实验数据来分析政治关联对企业价值效益的影响.结果表明政府关联是关键的因素并且在中国对中小型企业的价值具有负面影响。
2重要内容翻译2。
1引言在商业界,有越来越多关于政治关联的影响的经济研究。
它们发现政治关联能够帮助企业确保有利的规章条件以及成功获得资源，比如能够最终提高企业价值或是提升绩效的银行贷款，这种政治关联的影响在不同的经济条件下呈现不同的效果。
在高腐败和法律制度薄弱的国家，政治关联对企业价值具有决定性因素1的作用.中国由高度集权的计划经济向市场经济转变，政府对市场具有较强的控制作用，而且有大量的上市企业具有政治关联。
中小型企业发展的很迅速，他们已经在全球经济环境中变得越来越重要。
从90年代起, 政治因素对中国的任何规模的企业来说都变得越来越重要,尤其是中小型企业的价值。
和其他的部门相比较，中小型企业只有较小的现金流，不稳定的现金流且高负债率.一方面，中小型企业改变更加灵活；另一方面,中小型企业在由于企业规模以及对银行来说没有可以抵押的资产，在筹资方面较为困难。
企业如何应对微观经济环境和政策去保证正常的企业活动，并且政治关联如何影响企业价值？这篇论文调查政治关联和企业价值之间的联系,并且试图去研究企业是否可以从政治关联中获利提升企业价值。
2.2定义这些中小型企业之所以叫中小型企业，是和管理规模有关。
对这些小企业来说，雇员很少，营业额较低,资金一般由较少的人提供,因此，通常由这些业主直接管理企业。
文献综述及外文文献翻译
⽂献综述及外⽂⽂献翻译华中科技⼤学⽂华学院毕业设计（论⽂）外⽂⽂献翻译（本科学⽣⽤）题⽬：Plc based control system for the music fountain 学⽣姓名：_周训⽅___学号：060108011117 学部（系）: 信息学部专业年级: _06⾃动化（1）班_指导教师：张晓丹___职称或学位：助教__20 年⽉⽇外⽂⽂献翻译（译成中⽂1000字左右）：【主要阅读⽂献不少于5篇，译⽂后附注⽂献信息，包括：作者、书名（或论⽂题⽬）、出版社（或刊物名称）、出版时间（或刊号）、页码。
提供所译外⽂资料附件（印刷类含封⾯、封底、⽬录、翻译部分的复印件等，⽹站类的请附⽹址及原⽂】英⽂节选原⽂：Central Processing Unit (CPU) is the brain of a PLC controller. CPU itself is usually one of the microcontrollers. Aforetime these were 8-bit microcontrollers such as 8051, and now these are 16-and 32-bit microcontrollers. Unspoken rule is that you’ll find mostly Hitachi and Fujicu microcontrollers in PLC controllers by Japanese makers, Siemens in European controllers, and Motorola microcontrollers in American ones. CPU also takes care of communication, interconnectedness among other parts of PLC controllers, program execution, memory operation, overseeing input and setting up of an output. PLC controllers have complex routines for memory checkup in order to ensure that PLC memory was not damaged (memory checkup is done for safety reasons).Generally speaking, CPU unit makes a great number of check-ups of the PLC controller itself so eventual errors would be discovered early. You can simply look at any PLC controller and see that there are several indicators in the form. of light diodes for error signalization.System memory (today mostly implemented in FLASH technology) is used by a PLC for a process control system. Aside form. this operating system it also contains a user program translated forma ladder diagram to a binary form. FLASH memory contents can be changed only in case where user program is being changed. PLC controllers were used earlier instead of PLASH memory and have had EPROM memory instead of FLASH memory which had to be erased with UV lamp and programmed on programmers. With the use of FLASH technology this process was greatly shortened. Reprogramming a program memory is done through a serial cable in a program for application development.User memory is divided into blocks having special functions. Some parts of a memory are used for storing input and output status. The real status of an input is stored either as “1”or as “0”in a specific memory bit/ each input or output has one corresponding b it in memory. Other parts of memory are used to store variable contents for variables used in used program. For example, time value, or counter value would be stored in this part of the memory.PLC controller can be reprogrammed through a computer (usual way), but also through manual programmers (consoles). This practically means that each PLC controller can programmed through a computer if you have the software needed for programming. Today’s transmission computers are ideal for reprogramming a PLC cont roller in factory itself. This is of great importance to industry. Once the system is corrected, it is also important to read the right program into a PLC again. It is also good to check from time to time whether program in a PLC has not changed. This helps to avoid hazardous situations in factory rooms (some automakers have established communication networks which regularly check programs in PLC controllers to ensure execution only of good programs). Almost every program for programming a PLC controller possesses various useful options such as: forced switching on and off of the system input/outputs (I/O lines),program follow up in real time as well as documenting a diagram. This documenting is necessary to understand and define failures and malfunctions. Programmer can add remarks, names of input or output devices, and comments that can be useful when finding errors, or with system maintenance. Adding comments and remarks enables any technician (and not just a person who developed the system) to understand a ladder diagram right away. Comments and remarks can even quote precisely part numbers if replacements would be needed. This would speed up a repair of any problems that come up due to bad parts. The old way was such that a person who developed a system had protection on the program, so nobody aside from this person could understand how it was done. Correctly documented ladder diagram allows any technician to understand thoroughly how system functions.Electrical supply is used in bringing electrical energy to central processing unit. Most PLC controllers work either at 24 VDC or 220 VAC. On some PLC controllers you’ll find electrical supply as a separate module. Those are usually bigger PLC controllers, while small and medium series already contain the supply module. User has to determine how much current to take from I/O module to ensure that electrical supply provides appropriate amount of current. Different types of modules use different amounts of electrical current. This electrical supply is usually not used to start external input or output. User has to provide separate supplies in starting PLC controller inputs because then you can ensure so called “pure” supply for the PLC controller. With pure supply we mean supply where industrial environment can not affect it damagingly. Some of the smaller PLC controllers supply their inputs with voltage from a small supply source already incorporated into a PLC.中⽂翻译：从结构上分，PLC分为固定式和组合式（模块式）两种。
毕业设计论文外文文献翻译
毕业设计(论文）外文文献翻译院系：财务与会计学院年级专业：201＊级财务管理姓名:学号：132148*＊*附件: 财务风险管理【Abstract】Although financial risk has increased significantly in recent years risk and risk management are not contemporary issues。
The result of increasingly global markets is that risk may originate with events thousands of miles away that have nothing to do with the domestic market。
Information is available instantaneously which means that change and subsequent market reactions occur very quickly。
The economic climate and markets can be affected very quickly by changes in exchange rates interest rates and commodity prices。
Counterparties can rapidly become problematic。
As a result it is important to ensure financial risks are identified and managed appropriately. Preparation is a key component of risk management。
【Key Words】Financial risk，Risk management，YieldsI. Financial risks arising1.1What Is Risk1.1.1The concept of riskRisk provides the basis for opportunity. The terms risk and exposure have subtle differences in their meaning. Risk refers to the probability of loss while exposure is the possibility of loss although they are often used interchangeably。
本科生英文文献翻译格式要求
外文文献翻译格式要求：外文文献翻译是本科生毕业的过程之一，有些格式需要我们注意一下。
（1）摘要，关键词：宋体五号（其中“摘要”和“关键词”为宋体五号加粗），行间距设置为18磅，段前段后间距设置为行，对齐方式选择“两端对齐”方式；各个关键词之间以分号（；）或者（，）隔开，最后一个关键词后不加标点；（2）正文一级标题：采用黑体小三号加粗，行间距设置为20磅，段前段后间距设置为行，一般采用“1 引言”样式，其中1和“引言”之间用一个空格分开；正文二级标题：采用黑体小三号，行间距设置为20磅，段前段后间距设置为行，一般采用“系统原理”样式，其中1和“系统原理”之间用一个空格分开；；一级标题和二级标题采用“左对齐”方式；（3）正文内容：采用宋体小四号，行间距设置为20磅，段前段后间距设置为0行，首行缩进2字符，正文对齐方式在段落格式设置中选择“两端对齐”，遇正文中有公式的，设置该行（段）行间距为“单倍行距”（4）插图：请设置图片版式为“浮于文字上方”，并勾选“居中”，图片大小根据版面，按比例适当进行缩放，图示说明采用“图 1 主控制器的结构图”样式置于图下，图序与说明以一个空格字符间隔，图示说明采用宋体五号，居中对齐，行间距设置为“单倍行距”，段前段后距设置为行；（5）表格：在表格属性中选择“居中”对齐方式，表格说明采用“表1 两种方法试验数据比较”样式置于表格上方，表序与说明以一个空格字符间隔，表格说明采用宋体五号，居中对齐，行间距设置为“单倍行距”，段前段后距设置为行；（6）参考文献：“参考文献”格式同一级标题格式，参考文献内容采用宋体五号，行间距设置为18磅，段前段后间距设置为0行，对齐方式选择“左对齐”方式，其中出现的标点一律采用英文标点；以上摘要，关键词，正文，标题及参考文献中出现的英文字符和数字，一律设置为“Times New Roman”字体。
外文文献翻译附于开题报告之后：第一部分为译文，第二部分为外文文献原文，译文与原文均需单独编制页码（底端居中）并注明出处。
毕业论文外文文献翻译
2013届本科生毕业论文英文参考文献翻译
Oracle虚拟机服务器软件虚拟化在一个64位
Linux环境的性能和可扩展性
（译文）
学院（系）：
信息工程
专业年级：
学生姓名：
指导教师：
合作指导教师：
完成日期：
2013年6月
Oracle虚拟机服务器软件虚拟化在一个64位Linux环境的性能和可扩展性
benefits, however, this has not been without its attendantproblems and anomalies, such as performance tuning anderratic performance metrics, unresponsive virtualized systems,crashed virtualized servers, misconfigured virtual hostingplatforms, amongst others. The focus of this research was theanalysis of the performance of the Oracle VM servervirtualization platform against that of the bare-metal serverenvironment. The scalability and its support for high volumetransactions were also analyzed using 30 and 50 active usersfor the performance evaluation. Swingbench and LMbench,two open suite benchmark tools were utilized in measuringperformance. Scalability was also measured using Swingbench.Evidential results gathered from Swingbench revealed 4% and8% overhead for 30 and 50 active users respectively in theperformance evaluation of Oracle database in a single OracleVM. Correspondingly, performance metric法
本科毕业论文外文文献翻译
本科毕业论文外文文献翻译本科毕业论文外文文献翻译随着全球化的不断发展，人们对外文文献的需求也越来越高。
尤其是在本科毕业论文的撰写过程中，引用和翻译外文文献是不可或缺的一部分。
本文将探讨本科毕业论文外文文献翻译的重要性以及一些技巧和注意事项。
首先，翻译外文文献对于本科毕业论文的写作至关重要。
外文文献是学术研究中的重要参考资料，可以帮助我们了解国外学者在相关领域的研究成果和观点。
通过引用外文文献，我们可以对研究问题进行深入分析和论证，提高论文的学术价值和可信度。
然而，翻译外文文献并非易事。
首先，我们需要具备良好的外语水平，特别是对于所研究领域的专业术语要有一定的了解。
其次，在翻译过程中，我们需要保持准确性和一致性。
准确性是指翻译内容要忠实于原文，不失原意。
一致性是指在整个论文中使用相同的术语和翻译方法，避免混淆读者。
在翻译外文文献时，我们还要注意一些技巧和细节。
首先，我们可以使用在线翻译工具来辅助翻译，但不能完全依赖它们。
在线翻译工具通常会存在一些语法和词汇错误，需要我们进行修正和改进。
其次，我们可以参考一些翻译指南和词典，特别是针对所研究领域的专业词汇。
这些资源可以帮助我们更准确地理解和翻译外文文献。
此外，我们还需要注意一些常见的翻译错误。
首先是直译错误，即直接将外文句子逐字逐句地翻译成中文，忽略了语言和文化的差异。
这样的翻译通常会造成中文表达不通顺和不自然的问题。
其次是漏译和误译，即在翻译过程中遗漏了一些重要信息或者错误地理解了原文的意思。
这些错误会导致我们对外文文献的理解和引用出现偏差。
在翻译外文文献的过程中，我们还应该注重文化因素的考虑。
不同的语言和文化背景下，同一概念可能有不同的表达方式。
因此，我们需要在翻译过程中充分考虑到文化差异，避免产生歧义和误解。
最后，我们还需要在引用外文文献时遵守学术道德和规范。
我们应该正确标注引用文献的来源和作者，避免抄袭和侵权行为。
同时，我们还应该遵循学术规范，不对外文文献进行删减、修改或者歪曲，保持原文的完整性和准确性。
毕设外文文献+翻译1
外文翻译外文原文CHANGING ROLES OF THE CLIENTS、ARCHITECTSAND CONTRACTORS THROUGH BIMAbstract:Purpose –This paper aims to present a general review of the practical implications of building information modelling (BIM) based on literature and case studies. It seeks to address the necessity for applying BIM and re-organising the processes and roles in hospital building projects. This type of project is complex due to complicated functional and technical requirements, decision making involving a large number of stakeholders, and long-term development processes.Design/methodology/approach–Through desk research and referring to the ongoing European research project InPro, the framework for integrated collaboration and the use of BIM are analysed.Findings –One of the main findings is the identification of the main factors for a successful collaboration using BIM, which can be recognised as “POWER”: product information sharing (P),organisational roles synergy (O), work processes coordination (W), environment for teamwork (E), and reference data consolidation (R).Originality/value –This paper contributes to the actual discussion in science and practice on the changing roles and processes that are required to develop and operate sustainable buildings with the support of integrated ICT frameworks and tools. It presents the state-of-the-art of European research projects and some of the first real cases of BIM application in hospital building projects.Keywords:Europe, Hospitals, The Netherlands, Construction works, Response flexibility, Project planningPaper type :General review1. IntroductionHospital building projects, are of key importance, and involve significant investment, and usually take a long-term development period. Hospital building projects are also very complex due to the complicated requirements regarding hygiene, safety, special equipments, and handling of a large amount of data. The building process is very dynamic and comprises iterative phases and intermediate changes. Many actors with shifting agendas, roles and responsibilities are actively involved, such as: the healthcare institutions, national and local governments, project developers, financial institutions, architects, contractors, advisors, facility managers, and equipment manufacturers and suppliers. Such building projects are very much influenced, by the healthcare policy, which changes rapidly in response to the medical, societal and technological developments, and varies greatly between countries (World Health Organization, 2000). In The Netherlands, for example, the way a building project in the healthcare sector is organised is undergoing a major reform due to a fundamental change in the Dutch health policy that was introduced in 2008.The rapidly changing context posts a need for a building with flexibility over its lifecycle. In order to incorporate life-cycle considerations in the building design, construction technique, and facility management strategy, a multidisciplinary collaboration is required. Despite the attempt for establishing integrated collaboration, healthcare building projects still faces serious problems in practice, such as: budget overrun, delay, and sub-optimal quality in terms of flexibility, end-user’s dissatisfaction, and energy inefficiency. It is evident that the lack of communication and coordination between the actors involved in the different phases of a building project is among the most important reasons behind these problems. The communication between different stakeholders becomes critical, as each stakeholder possesses different setof skills. As a result, the processes for extraction, interpretation, and communication of complex design information from drawings and documents are often time-consuming and difficult. Advanced visualisation technologies, like 4D planning have tremendous potential to increase the communication efficiency and interpretation ability of the project team members. However, their use as an effective communication tool is still limited and not fully explored. There are also other barriers in the information transfer and integration, for instance: many existing ICT systems do not support the openness of the data and structure that is prerequisite for an effective collaboration between different building actors or disciplines.Building information modelling (BIM) offers an integrated solution to the previously mentioned problems. Therefore, BIM is increasingly used as an ICT support in complex building projects. An effective multidisciplinary collaboration supported by an optimal use of BIM require changing roles of the clients, architects, and contractors; new contractual relationships; and re-organised collaborative processes. Unfortunately, there are still gaps in the practical knowledge on how to manage the building actors to collaborate effectively in their changing roles, and to develop and utilise BIM as an optimal ICT support of the collaboration.This paper presents a general review of the practical implications of building information modelling (BIM) based on literature review and case studies. In the next sections, based on literature and recent findings from European research project InPro, the framework for integrated collaboration and the use of BIM are analysed. Subsequently, through the observation of two ongoing pilot projects in The Netherlands, the changing roles of clients, architects, and contractors through BIM application are investigated. In conclusion, the critical success factors as well as the main barriers of a successful integrated collaboration using BIM are identified.2. Changing roles through integrated collaboration and life-cycle design approachesA hospital building project involves various actors, roles, and knowledge domains. In The Netherlands, the changing roles of clients, architects, and contractors in hospital building projects are inevitable due the new healthcare policy. Previously under the Healthcare Institutions Act (WTZi), healthcare institutions were required to obtain both a license and a building permit for new construction projects and major renovations. The permit was issued by the Dutch Ministry of Health. The healthcare institutions were then eligible to receive financial support from the government. Since 2008, new legislation on the management of hospital building projects and real estate has come into force. In this new legislation, a permit for hospital building project under the WTZi is no longer obligatory, nor obtainable (Dutch Ministry of Health, Welfare and Sport, 2008). This change allows more freedom from the state-directed policy, and respectively, allocates more responsibilities to the healthcare organisations to deal with the financing and management of their real estate. The new policy implies that the healthcare institutions are fully responsible to man age and finance their building projects and real estate. The government’s support for the costs of healthcare facilities will no longer be given separately, but will be included in the fee for healthcare services. This means that healthcare institutions must earn back their investment on real estate through their services. This new policy intends to stimulate sustainable innovations in the design, procurement and management of healthcare buildings, which will contribute to effective and efficient primary healthcare services.The new strategy for building projects and real estate management endorses an integrated collaboration approach. In order to assure the sustainability during construction, use, and maintenance, the end-users, facility managers, contractors and specialist contractors need to be involved in the planning and design processes. The implications of the new strategy are reflected in the changing roles of the building actors and in the new procurement method.In the traditional procurement method, the design, and its details, are developed by the architect, and design engineers. Then, the client (the healthcare institution) sends an application to the Ministry of Healthto obtain an approval on the building permit and the financial support from the government. Following this, a contractor is selected through a tender process that emphasises the search for the lowest-price bidder. During the construction period, changes often take place due to constructability problems of the design and new requirements from the client. Because of the high level of technical complexity, and moreover, decision-making complexities, the whole process from initiation until delivery of a hospital building project can take up to ten years time. After the delivery, the healthcare institution is fully in charge of the operation of the facilities. Redesigns and changes also take place in the use phase to cope with new functions and developments in the medical world.The integrated procurement pictures a new contractual relationship between the parties involved in a building project. Instead of a relationship between the client and architect for design, and the client and contractor for construction, in an integrated procurement the client only holds a contractual relationship with the main party that is responsible for both design and construction. The traditional borders between tasks and occupational groups become blurred since architects, consulting firms, contractors, subcontractors, and suppliers all stand on the supply side in the building process while the client on the demand side. Such configuration puts the architect, engineer and contractor in a very different position that influences not only their roles, but also their responsibilities, tasks and communication with the client, the users, the team and other stakeholders.The transition from traditional to integrated procurement method requires a shift of mindset of the parties on both the demand and supply sides. It is essential for the client and contractor to have a fair and open collaboration in which both can optimally use their competencies. The effectiveness of integrated collaboration is also determined by the client’s capacity and strategy to organize innovative tendering procedures.A new challenge emerges in case of positioning an architect in a partnership with the contractor instead of with the client. In case of the architect enters a partnership with the contractor, an important issues is how to ensure the realisation of the architectural values as well as innovative engineering through an efficient construction process. In another case, the architect can stand at the client’s side in a strategic advisory role instead of being the designer. In this case, the architect’s responsibility is translating client’s requirements and wishes into the architectural values to be included in the design specification, and evaluating the contractor’s proposal against this. In any of this new role, the architect holds the responsibilities as stakeholder interest facilitator, custodian of customer value and custodian of design models.The transition from traditional to integrated procurement method also brings consequences in the payment schemes. In the traditional building process, the honorarium for the architect is usually based on a percentage of the project costs; this may simply mean that the more expensive the building is, the higher the honorarium will be. The engineer receives the honorarium based on the complexity of the design and the intensity of the assignment. A highly complex building, which takes a number of redesigns, is usually favourable for the engineers in terms of honorarium. A traditional contractor usually receives the commission based on the tender to construct the building at the lowest price by meeting the minimum specifications given by the client. Extra work due to modifications is charged separately to the client. After the delivery, the contractor is no longer responsible for the long-term use of the building. In the traditional procurement method, all risks are placed with the client.In integrated procurement method, the payment is based on the achieved building performance; thus, the payment is non-adversarial. Since the architect, engineer and contractor have a wider responsibility on the quality of the design and the building, the payment is linked to a measurement system of the functional and technical performance of the building over a certain period of time. The honorarium becomes an incentive to achieve the optimal quality. If the building actors succeed to deliver a higher added-value thatexceed the minimum client’s requirements, they will receive a bonus in accordance to the client’s extra gain. The level of transparency is also improved. Open book accounting is an excellent instrument provided that the stakeholders agree on the information to be shared and to its level of detail (InPro, 2009).Next to the adoption of integrated procurement method, the new real estate strategy for hospital building projects addresses an innovative product development and life-cycle design approaches. A sustainable business case for the investment and exploitation of hospital buildings relies on dynamic life-cycle management that includes considerations and analysis of the market development over time next to the building life-cycle costs (investment/initial cost, operational cost, and logistic cost). Compared to the conventional life-cycle costing method, the dynamic life-cycle management encompasses a shift from focusing only on minimizing the costs to focusing on maximizing the total benefit that can be gained. One of the determining factors for a successful implementation of dynamic life-cycle management is the sustainable design of the building and building components, which means that the design carries sufficient flexibility to accommodate possible changes in the long term (Prins, 1992).Designing based on the principles of life-cycle management affects the role of the architect, as he needs to be well informed about the usage scenarios and related financial arrangements, the changing social and physical environments, and new technologies. Design needs to integrate people activities and business strategies over time. In this context, the architect is required to align the design strategies with the organisational, local and global policies on finance, business operations, health and safety, environment, etc.The combination of process and product innovation, and the changing roles of the building actors can be accommodated by integrated project delivery or IPD (AIA California Council, 2007). IPD is an approach that integrates people, systems, business structures and practices into a process that collaboratively harnesses the talents and insights of all participants to reduce waste and optimize efficiency through all phases of design, fabrication and construction. IPD principles can be applied to a variety of contractual arrangements. IPD teams will usually include members well beyond the basic triad of client, architect, and contractor. At a minimum, though, an Integrated Project should include a tight collaboration between the client, the architect, and the main contractor ultimately responsible for construction of the project, from the early design until the project handover. The key to a successful IPD is assembling a team that is committed to collaborative processes and is capable of working together effectively. IPD is built on collaboration. As a result, it can only be successful if the participants share and apply common values and goals.3. Changing roles through BIM applicationBuilding information model (BIM) comprises ICT frameworks and tools that can support the integrated collaboration based on life-cycle design approach. BIM is a digital representation of physical and functional characteristics of a facility. As such it serves as a shared knowledge resource for information about a facility forming a reliable basis for decisions during its lifecycle from inception onward (National Institute of Building Sciences NIBS, 2007). BIM facilitates time and place independent collaborative working. A basic premise of BIM is collaboration by different stakeholders at different phases of the life cycle of a facility to insert, extract, update or modify information in the BIM to support and reflect the roles of that stakeholder. BIM in its ultimate form, as a shared digital representation founded on open standards for interoperability, can become a virtual information model to be handed from the design team to the contractor and subcontractors and then to the client.BIM is not the same as the earlier known computer aided design (CAD). BIM goes further than an application to generate digital (2D or 3D) drawings. BIM is an integrated model in which all process and product information is combined, stored, elaborated, and interactively distributed to all relevant building actors. As a central model for all involved actors throughout the project lifecycle, BIM develops andevolves as the project progresses. Using BIM, the proposed design and engineering solutions can be measured against the client’s requirements and expected building performance. The functionalities of BIM to support the design process extend to multidimensional (nD), including: three-dimensional visualisation and detailing, clash detection, material schedule, planning, cost estimate, production and logistic information, and as-built documents. During the construction process, BIM can support the communication between the building site, the factory and the design office– which is crucial for an effective and efficient prefabrication and assembly processes as well as to prevent or solve problems related to unforeseen errors or modifications. When the building is in use, BIM can be used in combination with the intelligent building systems to provide and maintain up-to-date information of the building performance, including the life-cycle cost.To unleash the full potential of more efficient information exchange in the AEC/FM industry in collaborative working using BIM, both high quality open international standards and high quality implementations of these standards must be in place. The IFC open standard is generally agreed to be of high quality and is widely implemented in software. Unfortunately, the certification process allows poor quality implementations to be certified and essentially renders the certified software useless for any practical usage with IFC. IFC compliant BIM is actually used less than manual drafting for architects and contractors, and show about the same usage for engineers. A recent survey shows that CAD (as a closed-system) is still the major form of technique used in design work (over 60 per cent) while BIM is used in around 20 percent of projects for architects and in around 10 per cent of projects for engineers and contractors.The application of BIM to support an optimal cross-disciplinary and cross-phase collaboration opens a new dimension in the roles and relationships between the building actors. Several most relevant issues are: the new role of a model manager; the agreement on the access right and Intellectual Property Right (IPR); the liability and payment arrangement according to the type of contract and in relation to the integrated procurement; and the use of open international standards.Collaborative working using BIM demands a new expert role of a model manager who possesses ICT as well as construction process know-how (InPro, 2009). The model manager deals with the system as well as with the actors. He provides and maintains technological solutions required for BIM functionalities, manages the information flow, and improves the ICT skills of the stakeholders. The model manager does not take decisions on design and engineering solutions, nor the organisational processes, but his roles in the chain of decision making are focused on:the development of BIM, the definition of the structure and detail level of the model, and the deployment of relevant BIM tools, such as for models checking, merging, and clash detections;the contribution to collaboration methods, especially decision making and communication protocols, task planning, and risk management;and the management of information, in terms of data flow and storage, identification of communication errors, and decision or process (re-)tracking.Regarding the legal and organisational issues, one of the actual questions is: “In what way does the intellectual property right (IPR) in collaborative working using BIM differ from the IPR in a traditional teamwork?”. In terms of combined work, the IPR of each element is at tached to its creator. Although it seems to be a fully integrated design, BIM actually resulted from a combination of works/elements; for instance: the outline of the building design, is created by the architect, the design for the electrical system, is created by the electrical contractor, etc. Thus, in case of BIM as a combined work, the IPR is similar to traditional teamwork. Working with BIM with authorship registration functionalities may actually make it easier to keep track of the IPR.How does collaborative working, using BIM, effect the contractual relationship? On the one hand,collaborative working using BIM does not necessarily change the liability position in the contract nor does it obligate an alliance contract. The General Principles of BIM A ddendum confirms: ‘This does not effectuate or require a restructuring of contractual relationships or shifting of risks between or among the Project Participants other than as specifically required per the Protocol Addendum and its Attachments’ (ConsensusDOCS, 2008). On the other hand, changes in terms of payment schemes can be anticipated. Collaborative processes using BIM will lead to the shifting of activities from to the early design phase. Much, if not all, activities in the detailed engineering and specification phase will be done in the earlier phases. It means that significant payment for the engineering phase, which may count up to 40 per cent of the design cost, can no longer be expected. As engineering work is done concurrently with the design, a new proportion of the payment in the early design phase is necessary.4. Review of ongoing hospital building projects using BIMIn The Netherlands, the changing roles in hospital building projects are part of the strategy, which aims at achieving a sustainable real estate in response to the changing healthcare policy. Referring to literature and previous research, the main factors that influence the success of the changing roles can be concluded as: the implementation of an integrated procurement method and a life-cycle design approach for a sustainable collaborative process; the agreement on the BIM structure and the intellectual rights; and the integration of the role of a model manager. The preceding sections have discussed the conceptual thinking on how to deal with these factors effectively. This current section observes two actual projects and compares the actual practice with the conceptual view respectively.The main issues, which are observed in the case studies, are:the selected procurement method and the roles of the involved parties within this method;the implementation of the life-cycle design approach;the type, structure, and functionalities of BIM used in the project;the openness in data sharing and transfer of the model, and the intended use of BIM in the future; and the roles and tasks of the model manager.The pilot experience of hospital building projects using BIM in the Netherlands can be observed at University Medical Centre St Radboud (further referred as UMC) and Maxima Medical Centre (further referred as MMC). At UMC, the new building project for the Faculty of Dentistry in the city of Nijmegen has been dedicated as a BIM pilot project. At MMC, BIM is used in designing new buildings for Medical Simulation and Mother-and-Child Centre in the city of Veldhoven.The first case is a project at the University Medical Centre (UMC) St Radboud. UMC is more than just a hospital. UMC combines medical services, education and research. More than 8500 staff and 3000 students work at UMC. As a part of the innovative real estate strategy, UMC has considered to use BIM for its building projects. The new development of the Faculty of Dentistry and the surrounding buildings on the Kapittelweg in Nijmegen has been chosen as a pilot project to gather practical knowledge and experience on collaborative processes with BIM support.The main ambition to be achieved through the use of BIM in the building projects at UMC can be summarised as follows:using 3D visualisation to enhance the coordination and communication among the building actors, and the user participation in design;integrating the architectural design with structural analysis, energy analysis, cost estimation, and planning;interactively evaluating the design solutions against the programme of requirements and specifications;reducing redesign/remake costs through clash detection during the design process; andoptimising the management of the facility through the registration of medical installations andequipments, fixed and flexible furniture, product and output specifications, and operational data.The second case is a project at the Maxima Medical Centre (MMC). MMC is a large hospital resulted from a merger between the Diaconessenhuis in Eindhoven and St Joseph Hospital in Veldhoven. Annually the 3,400 staff of MMC provides medical services to more than 450,000 visitors and patients. A large-scaled extension project of the hospital in Veldhoven is a part of its real estate strategy. A medical simulation centre and a women-and-children medical centre are among the most important new facilities within this extension project. The design has been developed using 3D modelling with several functionalities of BIM.The findings from both cases and the analysis are as follows. Both UMC and MMC opted for a traditional procurement method in which the client directly contracted an architect, a structural engineer, and a mechanical, electrical and plumbing (MEP) consultant in the design team. Once the design and detailed specifications are finished, a tender procedure will follow to select a contractor. Despite the choice for this traditional method, many attempts have been made for a closer and more effective multidisciplinary collaboration. UMC dedicated a relatively long preparation phase with the architect, structural engineer and MEP consultant before the design commenced. This preparation phase was aimed at creating a common vision on the optimal way for collaboration using BIM as an ICT support. Some results of this preparation phase are: a document that defines the common ambition for the project and the collaborative working process and a semi-formal agreement that states the commitment of the building actors for collaboration. Other than UMC, MMC selected an architecture firm with an in-house engineering department. Thus, the collaboration between the architect and structural engineer can take place within the same firm using the same software application.Regarding the life-cycle design approach, the main attention is given on life-cycle costs, maintenance needs, and facility management. Using BIM, both hospitals intend to get a much better insight in these aspects over the life-cycle period. The life-cycle sustainability criteria are included in the assignments for the design teams. Multidisciplinary designers and engineers are asked to collaborate more closely and to interact with the end-users to address life-cycle requirements. However, ensuring the building actors to engage in an integrated collaboration to generate sustainable design solutions that meet the life-cycle performance expectations is still difficult. These actors are contracted through a traditional procurement method. Their tasks are specific, their involvement is rather short-term in a certain project phase, their responsibilities and liabilities are limited, and there is no tangible incentive for integrated collaboration.From the current progress of both projects, it can be observed that the type and structure of BIM relies heavily on the choice for BIM software applications. Revit Architecture and Revit Structure by Autodesk are selected based on the argument that it has been widely used internationally and it is compatible with AutoCAD, a widely known product of the same software manufacturer. The compatibility with AutoCAD is a key consideration at MMC since the drawings of the existing buildings were created with this application. These 2D drawings were then used as the basis to generate a 3D model with the BIM software application. The architectural model generated with Revit Architecture and the structural model generated by Revit Structure can be linked directly. In case of a change in the architectural model, a message will be sent to the structural engineer. He can then adjust the structural model, or propose a change in return to the architect, so that the structural model is always consistent with the architectural one.Despite the attempt of the design team to agree on using the same software application, the MEP consultant is still not capable to use Revit; and therefore, a conversion of the model from and to Revit is still required. Another weakness of this “closed approach”, which is dependent to the use of the same software applications, may appear in the near future when the project further progresses into the construction phase. If the contractor uses another software application, considerable extra work will be needed to make the model creted during the design phase to be compatible for use in the construction phase.。
外文文献翻译
本科毕业生外文文献翻译中国·大庆2014 年 5 月DS1302 trickle charge timekeeping chip Abstract: Introduces the United States with DALLAS trickle charge current capacity of small low-power real time clock DS1302 circuit structure, working principle and its application in real-time display of application time. It can be years, months, days, weekdays, hours, minutes, seconds for time, and has multiple functions, such as a leap year compensation. DS1302 are given in the C51 to read and write procedures and flow chart, as well as in the process of debugging note.Keywords: clock circuit; real-time clock; singlechip; Application1 IntroductionNow popular in many of the serial clock circuit, such as the DS1302, DS1307, PCF8485, etc.. These circuits interface is simple, inexpensive and easy to use, has been widely used. This paper introduces the DS1302 real time clock circuit is DALLAS's a small trickle charge current of the circuit capacity, the main feature is the use of serial data transmission, can provide programmable power-down protection functions of charge and can be shut down charging functions . 32.768kHz crystal ordinary.2 DS1302's structure and working principleDALLAS companies DS1302 is the United States launched a high-performance, low power consumption, with real-time clock circuit of the RAM, it can be years, months, days, weekdays, hours, minutes, seconds for time, with leap year compensation, the working voltage to 2.5V ~ 5.5V. The use of three-wire interface for synchronous communication with the CPU, and the use of unexpected ways to send more than one byte of data clock signal, or RAM. DS1302 within a 31 × 8 for the temporary storage of the RAM data register. DS1302 is the DS1202 to upgrade products, compatible with the DS1202, but the increase of the main power supply / back-pin dual power supply, while providing the power back to the small trickle charge current capacity.FEATURES● 1 Real-Time Clock Counts Seconds, Minutes, Hours, Date of the Month, Month,Day of the Week, and Year with Leap-Year Compensation Valid Up to 2100● 2 31 x 8 Battery-Backed General-Purpose RAM● 3 Serial I/O for Minimum Pin Count● 3 2.0V to 5.5V Full Operation● 4 Uses Less than 300nA at 2.0V● 5 Single-Byte or Multiple-Byte (Burst Mode) Data Transfer for Read or Write ofClock or RAM Data● 6 8-Pin DIP or Optional 8-Pin SO for Surface Mount●7 Simple 3-Wire Interface●8 TTL-Compatible (VCC = 5V)●9 Optional Industrial Temperature Range: -40°C to +85°C2.1 Pin function and structurePIN DESCRIPTION1)X1, X2 – 32.768 kHz Crystal Pins2)GND – Ground3)RST – Reset4)I/O – Data Input/Output5)SCLK – Serial Clock6)V CC1, V CC2 – Power Supply PinsFigure 1 showing a pin of the DS1302, which Vcc1 for back-up power supply, VCC2-based power. In the main power off, the clock is also able to maintain continuous operation. Vcc2 by the DS1302 or whichever Vcc1 the greater power. When Vcc2 than Vcc1 +0.2 V when, Vcc2 power supply to the DS1302. When Vcc1 less than Vcc2 when, DS1302 powered by Vcc1. X1 and X2 is the source of oscillation, an external 32.768kHz crystal. RST is the reset / chip select lines, through the RST input high drive home to start all of the data transfer. RST input has two functions: First, RST access control logic, allowing the address / command sequence into the shift register; Secondly, RST to terminate the provision of single-byte or multi-byte data transmission. When RST is high, all data are initialized to allow the DS1302 to operate on. If in the course ofRST sent home for the low, it will terminate the data transfer, I / O pin into high impedance state. Run-time power, Vcc ≥ 2.5V in before, RST must remain low. SCLK low only when the RST can be set to high. I / O for serial data input and output side (two-way), followed by a detailed description. Is always the SCLK input.2.2 DS1302 control byteDS1302 control word as shown in Figure 2. Control byte MSB (bit 7) must be logic 1, if it is 0, are not able to write data in the DS1302, bit 6 if 0, then the calendar clock and data access, that access to RAM to 1 data; bit 5 to bit 1 of the address unit instructions; least significant bit (bit 0) in the case of 0 to write to, read to 1, said operation, the control byte is always the beginning of the output from the lowest bit.2.3 Data input and output (I / O)Instruction word in the control input of the next clock rising edge of SCLK, the data is written into the DS1302, data input from the low enthronement 0. Similarly, in the following 8-bit instruction word control after the next falling edge of SCLK pulse to read out the DS1302 data,read the data from 0 to 7 .2.4 DS1302 registerDS1302 there are 12 registers, which register with the seven calendar, clock related data stored in digital form as a BCD code, the calendar and time registers and control words in Table 1.In addition, DS1302 year also register, control register, the charge register, the clock register and emergency-related registers, such as RAM. Clock burst read and write registers in addition to the order of one-time charge outside the register contents of all registers. DS1302 registers associated with the RAM is divided into two types: one is a single RAM unit, a total of 31, each module configuration for an 8-bit bytes, the command control words C0H ~ FDH, in which odd-numbered for the read operation, even for the write operation; the other for the sudden manner of RAM registers, this approach can be a one-time read and write all 31 bytes of RAM, a command control word for the FEH (write), FFH (Reading).3 DS1302 real-time display of time hardware and softwareDS1302 connection with the CPU needs three lines, namely, SCLK (7), I / O (6), RST (5).3.1 DS1302 connection with the CPUIn fact, in the debugger when the capacitor can not only add to a 32.768kHz crystal. Only when the choice of crystal, different crystal, error as well. In addition, the circuitcan be added to the above DS18B20, at the same time show the real-time temperature. CPU as long as the occupation of a line I can. LCD can be replaced with LED, can also use the letter Wei Jie Beijing Science and Technology Development Co., Ltd. produced 10 multi-purpose 8 LCD Module LCM101, containing watchdog (WDT) / clock generator and the two frequency beep driver circuit and a built-display RAM, any field can be displayed strokes, with a 3-4 line serial interface of any single-chip, IC interface. Low power consumption when the current show 2μA (typical value), power-saving mode is less than 1μA, working voltage is 2.4V ~ 3.3V, show clear.3.2 DS1302 real-time flow of timeSingle-byte read and single-byte writeDS1302 data exchange with the microprocessor, the first microprocessor to the circuit by sending the command byte, command byte highest MSB (D7) must be a logic 1, if D7 = 0, then the prohibition of writing DS1302, that is write-protected; D6 = 0, the designated clock and data, D6 = 1, designated RAM data; D5 ~ D1 designated a specific input or output register; lowest LSB (D0) to logic 0, the specified write operation (input), D0 = 1, the designated time operations (output).Calendar clock in the DS1302 or RAM for data transmission, DS1302 must first send a command byte. If a single byte transmission, 8-bit command byte sent after the end of the next two cycles of rising edge of SCLK input data byte, or 8 the next falling edge of SCLK cycle, the output data bytes.DS1302 registers associated with the RAM is divided into two types: one is a single RAM unit, a total of 31, each module configuration for an 8-bit bytes, the command control words C0H ~ FDH, in which odd-numbered for the read operation, even for the write operation; and then a class for the sudden manner of RAM register in this mannercan be a one-time reading, writing all 31 bytes of RAM.Special note is the back-up power supply B1, can use batteries or super capacitors (0.1F and above). Although the DS1302 in the main power after the power down very small, but if the clock to ensure the normal time, the best selection of small rechargeable batteries. Can be used on the old computer motherboard 3.6V rechargeable batteries. If a shorter time off (hours or days), the leakage can be used on a smaller electrolytic capacitors instead of the ordinary. 100 μF to 1 hour to ensure the normal travel time. DS1302 power in the first, you must initialize operation. After initialization method can be adjusted in accordance with the normal time.4 ConclusionThe existence of DS1302 clock accuracy is not high, the vulnerability of the environmental impact of the shortcomings of the chaos emerged clock. DS1302 can be used for data recording, in particular, is of special significance for some of the data points of the record data and time to which the data recorded at the same time. This record of long-term results of continuous monitoring and control system analysis and data on the causes abnormal finding of great significance. Traditional data record is separated from time to time when the sample or samples, there is no record of a specific time, therefore, can not only keep data accurate records of their time there; if the use of single-chip timing, on the one hand, require the use of counters, occupied by the hardware resources On the other hand, the need for interruption, and other inquiries, the same cost single-chip resources, and may not allow some monitoring and control system. However, if used in the system clock chip DS1302, can well solve the problem.DS1302涓流充电计时芯片摘要：介绍美国DALLAS公司推出的具有涓细电流充电能力的低功耗实时时钟电路DS1302的结构、工作原理及其在实时显示时间中的应用。
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本科毕业生外文文献翻译本科毕业生外文文献翻译学生姓名：***指导教师：***所在学院：信息技术学院专业：通信工程中国·大庆2011 年 5 月[原文]Industrial Ethernet and Intelligent Building 1 Industrial Ethernet the background1.1 Unified field bus standards dashed, the temptation remainsIn 1984 the United States proceed to develop international standards field bus, a few years, the major companies for commercial interests, Field bus standards can not always uniform. Through multiple voting, consultation, in January 2000 announced that the field bus international standards IEC61158 will be eight bus (Prefabs, Interfuse, P-NET, World, etc.)at the same time as international standards (currently has 10 kinds), formed The outcome of a compromise.At the same time, major foreign companies have also launched its own standards, such as LONWORKS, CAN, Japan's Mitsubishi, France Schneider, the current number of bus standards at the same time the situation still exists, they say the openness and interoperability only At the same can be achieved under a bus standard, different standards between the bus is still limited. The interconnection between different bus and can not be guaranteed, so people in their efforts to seek a unified standard field bus, some people have proposed the use of TCP / IP protocol Ethernet.1.2 The demand for system integration（1）industrial automation control integrated enterprise information is China's national policy to create automation and information technology as an example: In the need to change the business processes of the same time, management informationsystems and e-commerce, decentralized network of manufacturers to be integrated, the existing enterprise resource ERP transformed intoWEB-based applications. The current single from the automation of industrial automation, factory automation, to the development of automation systems, the underlying message should be integrated into the upper information online in order to achieve the integration of control as shown in an integrated system.Modern production system for a multi-storey industrial control systems, generally fall into three tiers:• Equipment-testing equipment and connectivity implementing agencies;• Control of the data obtained from the scene equipment, complete the various control, monitoring operating parameters, alarm and historical trend analysis;• Information layer will control the data processing system after spread to the higher level managementnetwork (TCP / IP Ethernet), in order to achieve integrated management of its network structure 。
（2）Intelligent Building of the urban information system integration, the development of digital, intelligent building (including intelligent residential district), has become a digital city's information site, in order to achieve information sharing, the need to achieve control network and information network of vertical integration, that is, Control network and TCP / IP Ethernet integration.As various subsystems and communications equipment at the scene agreement is diversified and integrated these two models must be developed gateways, in order to achieve the conversion agreement and unity, this has increased the complexity of system integration technology and increase costs. It was boldly put forward can use TCP / IP protocol as a unified agreement, the scene of the subsystems and equipment directly from Ethernet to simplify the system integration of technical difficulty, lower costs, so that controlsignals directly from the Ethernet transmission, So the concept of industrial Ethernet has been raised.2 Ethernet and CSMA / CD2.1 EthernetEthernet (Ethernet) 1975 by the United States XEROX company successfully developed, as a passive medium (such as twisted pair, coaxial cable, etc.) to disseminate information, to the history of the spread of electromagnetic waves known as the "Ethernet" (Ether ) To name.1980 by the DEC, INTEL, XEROX jointly launched a three EthernetV2, is the world's first LAN standard. 1983 IEEEE802 Committee DIX EthernetV2 based introduced IEEE803, using the CSMA / CD MAC technology. 802.3 refer to a CSMA / CD networks, and Ethernet DIX EthernetV2 from the standard definition, not strictly in the circumstances, can be called 802.3 LAN, which is Ethernet.To the modern manufacturing industry as an example, its modern manufacturing automation model in Figure .Industrial Ethernet is the commercial application of Ethernet to industrial control systems, the two networks is not essentially different from, the two are compatible.2.2CSMA / CD (Carrier Sense Multiple Access with Collision DetectionMulti-carrier monitoring visit / conflict detection)CSMA / CD are the first improvement comes from CSMA.（1）CSMA (Carrier monitor multiple access): stop trying to send a signal, first of all to monitor bus, to determine whether there is other media, to stop the signal.• If the media is free, you can send;• If the media are in working condition, then wait some try again after the interval, when heard in a busy state media, CSMA There are several different ways to deal with, the availability of interception ofsignal: adhere to non-CSMA, 1 - adhere to CSMA, P -- Consistently CSMA.（2）CSMA / CD to hear not only the first, but also Baiting Bain hair, a bus in the conflict, but once the conflict was detected; they stopped sending the frame, to give up their own frame. In order to know that other stations can also have a conflict, listening to the conflict to the bus station on the spread of a blocking signal interference, informed the bus station in the conflict have taken place, the capacity of this channel will not be sent because the frame was damaged and waste. With the increased network load, the collision would increase the opportunities, network efficiency decreased significantly.3 Industrial Ethernet the existing problemsField Bus is used for industrial control and complex and harsh environment of industrial design at the scene, the system of real-time and response time have strict demands on electricity use of the environment, there are special requirements. Since Ethernet is designed for information andcommunications, industrial control for the existence of the following questions:(1) using Ethernet CSMA / CD Access Protocol, which is a non-deterministic network.The high demand for real-time control systems, this uncertainty will result in the requested information can not convey. The so-called network segment is even shared the same bus network, you can listen to the message sent by the other side, at the same collision regional conflict (a conflict that will impact the region) of workstations and servers to connect the network area. For example, in a collision conflict in the region have a working group (from a server and workstation components multiple), when more than one visit a server workstation, due to the CSMA / CD bound by the same time allowing only a workstation and server Communications, can only wait for the other workstations. Competition for the workstation communication channel so that the communication workstations have delayed, and this extensionWhen the time is uncertain, workstations more competition for communications for the longer this situation known as the load was more severe the longer the waiting time.If in a collision domain, assume that two working groups, in a collision domain, the first work group servers, workstations access to competitive broadband networks (such as 100 M), another working group of all workstations and servers Are in a wait state and can not run. The two working groups to split the original broadband network (100 M), a working group work, must wait for another group, this has not only delayed, and this delay is uncertain. As CSMA / CD have unforeseen delay, particularly in the heavy load, the more real-time data transmission can not be guaranteed. Therefore Ethernet control system must be solved for real-time and uncertainty.(2) Ethernet in reliability than Bus at the scene.Field Bus is designed for industrial control, able to adapt flammable, explosive (such as chemicals, pharmaceuticals), strong interference andother occasions poor environment occasions. Field bus have shielding, grounding and explosion-proof measures, such as Ethernet and the need to address these issues.(3) Field bus specifications on the network segment with a power supply.For all non-self-powered equipment to power and Ethernet does not provide power, the need for additional electricity supply lines.4 feasibility of the application of Industrial EthernetIndustrial Ethernet for industrial control, the above-mentioned problems, with the Ethernet technology development and the implementation of corresponding measures, in fact, and the uncertainty can be made great improvements:(1) Continuously improve Ethernet rate: the rate in recent years Ethernet from 10 Mbps, 100Mbps to 1 000Mbps and has been widely applied. At present 10 Gaps Ethernet has been commercialized, greatly shortening the data transmission time, improve response time, thesystem's real-time and non uncertainties have improved.(2) using Ethernet switch technology: as the work site shared Ethernet channel competition arising from the conflict affected the collision of real-time system and uncertainty, Ethernet switch technology can be used to be improved. Ethernet-based exchange used in Ethernet switch, switch between the port at the same time can create a number of data channels, each connected to a network port, the port frame between the input and output no longer subject to CSMA / CD MAC bound by the agreement. When the system includes a number of working groups, in general so that each group formed a separate network segment, each of the occupation of the exchange network (of) a port (shown in Figure 4 switches are A, B, C, D 4 net), net of most of the time the work is independent, when any two of the need for information exchange network, the switch in two independent network of information between the channel .Once the end of the exchange of information, access is disconnected.This shows that switched Ethernet shared Ethernet can be overcome existing problems: • Switches on each port can connect a network segment; each of the network bandwidth can be exclusive;• switches on each port, the network of access between the independent and isolated, such as the need for inter-network of information and communication, it can temporarily establish an information channel, after the switch isolation, can greatly reduce the probability of conflict To improve the real-time and uncertainty;• switch VLAN technology commonly used to exchange control system can be allocated to the proprietary information, access and bandwidth, thus ensuring the network's busiest time, the control system is still comfortable enough bandwidth to enable Ethernet transmission of real-time information And uncertainty remained largely theoretical level.(3) In some applications to allow the circumstances: try to control network andinformation networks to use separate, in order to avoid real-time data and non-real-time data of the collision, between the industrial site for independent Ethernet network segment, Thereby improving the real-time and uncertainty. In addition, full-duplex technology can be used to reduce network load, and Ethernet + TCP / IP protocol on the basis of a uniform and apply to the industrial field of application-level control measures such as technical specifications. The above measures can be taken so that in some industrial Ethernet military, industrial, civilian areas of the site has been initially applied in the measurement and control. For example, many countries abroad nuclear accelerator as the Ethernet monitoring and control options, in addition automobile assembly line, thin steel production lines and so on a programmed of industrial Ethernet, monitoring and control from the direction of development of the area, the industrial Ethernet will be Monitoring is the future in the field of an important direction of development, but also the corporate-controlled integration and intelligentbuilding systems integration as a best option.(4) Ethernet power supply problem: over the years has been a defect, especially as IP phones, IP cameras, wireless AP, ENC (Ethernet Control System) system and other applications, more people put in Ethernet transmission Data at the same time, send some energy, small network equipment to meet the demand for electricity, power supply network equipment to solve the small state of disorder and the high cost of power supply wiring. So the IEEE 802.3af standard that is called out, has formed an Ethernet-powered international standards, 3 COM, Hawaii, DLINK, and other companies have with 802.3 aft-standard switching products. IEEE 802.3af standard is the core to meet the standards of 802.3 at the same time, by switching to the network terminal equipment to provide 48 V or 24 V power, the power supply to this industrial Ethernet issues have been very good solution, the principle shown in Figure 1.Figure 1 principle of self-powered Ethernet(5) Network of Ethernet: TCP / IP protocol is an open communication protocol. Security issues do not belong to form networks and TCP / IP protocol. Network security is the ultimate concern of the transmission network in the application layer of information security; it is not illegal changes to use. Protect the security of information transmission and either two ways: exclusive and independent access encrypted information. Before a way to let the lack should not be, the latter should not be the way to get the do not know. Ethernet virtual private network switching technology has become a basic network dedicated channel technology, already very mature and widely used. Ethernet can easily access will require isolation from. Internet information is encrypted TCP / IP on the basic nothing to do with the application of information processing methods.Prior to the issue of information is encrypted with information to carry out the use of declassified after treatment. Now basically an open encryption algorithms, do not rely on secret encryption guarantees, but by password (key). Information security key to the final and most important factor is the holder of the password; he kept using the password of course, and means the security communication system is the core.工业以太网与智能建筑1 工业以太网产生的背景1.1 统一现场总线标准成为泡影，诱惑依然1984年美国着手制定现场总线国际标准，若干年以来，世界各大公司为了商业的利益，现场总线标准始终不能统一。