毕业设计 外文翻译
毕设外文翻译是什么意思(两篇)

引言概述:在现代高等教育中,毕业设计(或称为毕业论文、学士论文等)是学生完成学业的重要环节。
而对于一些特定的专业,例如翻译专业,有时候还需要完成外文翻译这一项任务。
本文将探讨毕设外文翻译的意义和目的,以及为什么对翻译专业的学生而言这一任务极其重要。
正文内容:1.提高翻译能力和技巧外文翻译是一项对翻译专业学生而言十分重要的任务,通过进行外文翻译,学生们可以通过实践提高自己的翻译能力和技巧。
在这个过程中,他们可以学习如何处理不同类型的外文文本,熟悉不同领域的专业术语,并掌握一些常用的翻译技巧和策略。
2.扩展语言和文化知识毕设外文翻译要求学生们对翻译语言的相关知识和背景有一定的了解。
在进行翻译时,学生们需要遵循目标语言的语法规则,并确保所翻译的内容准确、清晰地传达源语言的意义。
通过这一过程,学生们可以进一步扩展自己的语言和文化知识,提高自己的跨文化沟通能力。
3.提供实践机会毕设外文翻译为学生们提供了一个实践的机会,让他们能够将在课堂上所学到的理论知识应用于实际操作中。
通过实践,学生们可以对所学知识的理解更加深入,同时也可以发现并解决实际翻译过程中的问题和挑战。
这对于学生们将来从事翻译工作时具备更好的实践能力和经验具有重要意义。
4.培养翻译专业素养毕设外文翻译要求学生们具备良好的翻译专业素养。
在进行翻译过程中,学生们需要保持专业的态度和责任心,严谨地对待每一个翻译任务。
他们需要学会如何进行翻译质量的评估和控制,以确保最终翻译稿的准确性和流畅性。
这一系列的要求和实践,可以帮助学生们培养出色的翻译专业素养。
5.提升自我学习和研究能力毕设外文翻译要求学生们进行广泛的文献阅读和研究,以便更好地理解所翻译的内容,并找到适当的翻译方法和策略。
在这个过程中,学生们需要培养自己的自主学习和研究能力,提高对学术和专业领域的敏感性,并能够独立思考和解决问题。
这将对学生们未来的学术研究和进一步的职业发展产生积极的影响。
总结:引言概述:毕业设计外文翻译(Thesis Translation)是指在毕业设计过程中,对相关外文文献进行翻译,并将其应用于研究中,以提供理论支持和参考。
毕业设计外文翻译_英文版

A Design and Implementation of Active NetworkSocket ProgrammingK.L. Eddie Law, Roy LeungThe Edward S. Rogers Sr. Department of Electrical and Computer EngineeringUniversity of TorontoToronto, Canadaeddie@, roy.leung@utoronto.caAbstract—The concept of programmable nodes and active networks introduces programmability into communication networks. Code and data can be sent and modified on their ways to destinations. Recently, various research groups have designed and implemented their own design platforms. Each design has its own benefits and drawbacks. Moreover, there exists an interoperability problem among platforms. As a result, we introduce a concept that is similar to the network socket programming. We intentionally establish a set of simple interfaces for programming active applications. This set of interfaces, known as Active Network Socket Programming (ANSP), will be working on top of all other execution environments in future. Therefore, the ANSP offers a concept that is similar to “write once, run everywhere.” It is an open programming model that active applications can work on all execution environments. It solves the heterogeneity within active networks. This is especially useful when active applications need to access all regions within a heterogeneous network to deploy special service at critical points or to monitor the performance of the entire networks. Instead of introducing a new platform, our approach provides a thin, transparent layer on top of existing environments that can be easily installed for all active applications.Keywords-active networks; application programming interface; active network socket programming;I. I NTRODUCTIONIn 1990, Clark and Tennenhouse [1] proposed a design framework for introducing new network protocols for the Internet. Since the publication of that position paper, active network design framework [2, 3, 10] has slowly taken shape in the late 1990s. The active network paradigm allows program code and data to be delivered simultaneously on the Internet. Moreover, they may get executed and modified on their ways to their destinations. At the moment, there is a global active network backbone, the ABone, for experiments on active networks. Apart from the immaturity of the executing platform, the primary hindrance on the deployment of active networks on the Internet is more on the commercially related issues. For example, a vendor may hesitate to allow network routers to run some unknown programs that may affect their expected routing performance. As a result, alternatives were proposed to allow active network concept to operate on the Internet, such as the application layer active networking (ALAN) project [4] from the European research community. In the ALAN project, there are active server systems located at different places in the networks and active applications are allowed to run in these servers at the application layer. Another potential approach from the network service provider is to offer active network service as the premium service class in the networks. This service class should provide the best Quality of Service (QoS), and allow the access of computing facility in routers. With this approach, the network service providers can create a new source of income.The research in active networks has been progressing steadily. Since active networks introduce programmability on the Internet, appropriate executing platforms for the active applications to execute should be established. These operating platforms are known as execution environments (EEs) and a few of them have been created, e.g., the Active Signaling Protocol (ASP) [12] and the Active Network Transport System (ANTS) [11]. Hence, different active applications can be implemented to test the active networking concept.With these EEs, some experiments have been carried out to examine the active network concept, for example, the mobile networks [5], web proxies [6], and multicast routers [7]. Active networks introduce a lot of program flexibility and extensibility in networks. Several research groups have proposed various designs of execution environments to offer network computation within routers. Their performance and potential benefits to existing infrastructure are being evaluated [8, 9]. Unfortunately, they seldom concern the interoperability problems when the active networks consist of multiple execution environments. For example, there are three EEs in ABone. Active applications written for one particular EE cannot be operated on other platforms. This introduces another problem of resources partitioning for different EEs to operate. Moreover, there are always some critical network applications that need to run under all network routers, such as collecting information and deploying service at critical points to monitor the networks.In this paper, a framework known as Active Network Socket Programming (ANSP) model is proposed to work with all EEs. It offers the following primary objectives.• One single programming interface is introduced for writing active applications.• Since ANSP offers the programming interface, the design of EE can be made independent of the ANSP.This enables a transparency in developing andenhancing future execution environments.• ANSP addresses the interoperability issues among different execution environments.• Through the design of ANSP, the pros and cons of different EEs will be gained. This may help design abetter EE with improved performance in future.The primary objective of the ANSP is to enable all active applications that are written in ANSP can operate in the ABone testbed . While the proposed ANSP framework is essential in unifying the network environments, we believe that the availability of different environments is beneficial in the development of a better execution environment in future. ANSP is not intended to replace all existing environments, but to enable the studies of new network services which are orthogonal to the designs of execution environments. Therefore, ANSP is designed to be a thin and transparent layer on top of all execution environments. Currently, its deployment relies on automatic code loading with the underlying environments. As a result, the deployment of ANSP at a router is optional and does not require any change to the execution environments.II. D ESIGN I SSUES ON ANSPThe ANSP unifies existing programming interfaces among all EEs. Conceptually, the design of ANSP is similar to the middleware design that offers proper translation mechanisms to different EEs. The provisioning of a unified interface is only one part of the whole ANSP platform. There are many other issues that need to be considered. Apart from translating a set of programming interfaces to other executable calls in different EEs, there are other design issues that should be covered, e.g., • a unified thread library handles thread operations regardless of the thread libraries used in the EEs;• a global soft-store allows information sharing among capsules that may execute over different environmentsat a given router;• a unified addressing scheme used across different environments; more importantly, a routing informationexchange mechanism should be designed across EEs toobtain a global view of the unified networks;• a programming model that should be independent to any programming languages in active networks;• and finally, a translation mechanism to hide the heterogeneity of capsule header structures.A. Heterogeneity in programming modelEach execution environment provides various abstractions for its services and resources in the form of program calls. The model consists of a set of well-defined components, each of them has its own programming interfaces. For the abstractions, capsule-based programming model [10] is the most popular design in active networks. It is used in ANTS [11] and ASP [12], and they are being supported in ABone. Although they are developed based on the same capsule model, their respective components and interfaces are different. Therefore, programs written in one EE cannot run in anther EE. The conceptual views of the programming models in ANTS and ASP are shown in Figure 1.There are three distinct components in ANTS: application, capsule, and execution environment. There exist user interfaces for the active applications at only the source and destination routers. Then the users can specify their customized actions to the networks. According to the program function, the applications send one or more capsules to carry out the operations. Both applications and capsules operate on top of an execution environment that exports an interface to its internal programming resources. Capsule executes its program at each router it has visited. When it arrives at its destination, the application at destination may either reply it with another capsule or presents this arrival event to the user. One drawback with ANTS is that it only allows “bootstrap” application.Figure 1. Programming Models in ASP and ANTS.In contrast, ASP does not limit its users to run “bootstrap” applications. Its program interfaces are different from ANTS, but there are also has three components in ASP: application client, environment, and AAContext. The application client can run on active or non-active host. It can start an active application by simply sending a request message to the EE. The client presents information to users and allows its users to trigger actions at a nearby active router. AAContext is the core of the network service and its specification is divided into two parts. One part specifies its actions at its source and destination routers. Its role is similar to that of the application in ANTS, except that it does not provide a direct interface with the user. The other part defines its actions when it runs inside the active networks and it is similar to the functional behaviors of a capsule in ANTS.In order to deal with the heterogeneity of these two models, ANSP needs to introduce a new set of programming interfaces and map its interfaces and execution model to those within the routers’ EEs.B. Unified Thread LibraryEach execution environment must ensure the isolation of instance executions, so they do not affect each other or accessThe authors appreciate the Nortel Institute for Telecommunications (NIT) at the University of Toronto to allow them to access the computing facilitiesothers’ information. There are various ways to enforce the access control. One simple way is to have one virtual machine for one instance of active applications. This relies on the security design in the virtual machines to isolate services. ANTS is one example that is using this method. Nevertheless, the use of multiple virtual machines requires relatively large amount of resources and may be inefficient in some cases. Therefore, certain environments, such as ASP, allow network services to run within a virtual machine but restrict the use of their services to a limited set of libraries in their packages. For instance, ASP provides its thread library to enforce access control. Because of the differences in these types of thread mechanism, ANSP devises a new thread library to allow uniform accesses to different thread mechanisms.C. Soft-StoreSoft-store allows capsule to insert and retrieve information at a router, thus allowing more than one capsules to exchange information within a network. However, problem arises when a network service can execute under different environments within a router. The problem occurs especially when a network service inserts its soft-store information in one environment and retrieves its data at a later time in another environment at the same router. Due to the fact that execution environments are not allowed to exchange information, the network service cannot retrieve its previous data. Therefore, our ANSP framework needs to take into account of this problem and provides soft-store mechanism that allows universal access of its data at each router.D. Global View of a Unified NetworkWhen an active application is written with ANSP, it can execute on different environment seamlessly. The previously smaller and partitioned networks based on different EEs can now be merging into one large active network. It is then necessary to advise the network topology across the networks. However, different execution environments have different addressing schemes and proprietary routing protocols. In order to merge these partitions together, ANSP must provide a new unified addressing scheme. This new scheme should be interpretable by any environments through appropriate translations with the ANSP. Upon defining the new addressing scheme, a new routing protocol should be designed to operate among environments to exchange topology information. This allows each environment in a network to have a complete view of its network topology.E. Language-Independent ModelExecution environment can be programmed in any programming language. One of the most commonly used languages is Java [13] due to its dynamic code loading capability. In fact, both ANTS and ASP are developed in Java. Nevertheless, the active network architecture shown in Figure 2 does not restrict the use of additional environments that are developed in other languages. For instance, the active network daemon, anted, in Abone provides a workspace to execute multiple execution environments within a router. PLAN, for example, is implemented in Ocaml that will be deployable on ABone in future. Although the current active network is designed to deploy multiple environments that can be in any programming languages, there lacks the tool to allow active applications to run seamlessly upon these environments. Hence, one of the issues that ANSP needs to address is to design a programming model that can work with different programming languages. Although our current prototype only considers ANTS and ASP in its design, PLAN will be the next target to address the programming language issue and to improve the design of ANSP.Figure 2. ANSP Framework Model.F. Heterogeneity of Capsule Header StructureThe structures of the capsule headers are different in different EEs. They carries capsule-related information, for example, the capsule types, sources and destinations. This information is important when certain decision needs to be made within its target environment. A unified model should allow its program code to be executed on different environments. However, the capsule header prevents different environments to interpret its information successfully. Therefore, ANSP should carry out appropriate translation to the header information before the target environment receives this capsule.III. ANSP P ROGRAMMING M ODELWe have outlined the design issues encountered with the ANSP. In the following, the design of the programming model in ANSP will be discussed. This proposed framework provides a set of unified programming interfaces that allows active applications to work on all execution environments. The framework is shown in Figure 2. It is composed of two layers integrated within the active network architecture. These two layers can operate independently without the other layer. The upper layer provides a unified programming model to active applications. The lower layer provides appropriate translation procedure to the ANSP applications when it is processed by different environments. This service is necessary because each environment has its own header definition.The ANSP framework provides a set of programming calls which are abstractions of ANSP services and resources. A capsule-based model is used for ANSP, and it is currently extended to map to other capsule-based models used in ANTSand ASP. The mapping possibility to other models remains as our future works. Hence, the mapping technique in ANSP allows any ANSP applications to access the same programming resources in different environments through a single set of interfaces. The mapping has to be done in a consistent and transparent manner. Therefore, the ANSP appears as an execution environment that provides a complete set of functionalities to active applications. While in fact, it is an overlay structure that makes use of the services provided from the underlying environments. In the following, the high-level functional descriptions of the ANSP model are described. Then, the implementations will be discussed. The ANSP programming model is based upon the interactions between four components: application client , application stub , capsule , and active service base.Figure 3. Information Flow with the ANSP.•Application Client : In a typical scenario, an active application requires some means to present information to its users, e.g., the state of the networks. A graphical user interface (GUI) is designed to operate with the application client if the ANSP runs on a non-active host.•Application Stub : When an application starts, it activates the application client to create a new instance of application stub at its near-by active node. There are two responsibilities for the application stub. One of them is to receive users’ instructions from the application client. Another one is to receive incoming capsules from networks and to perform appropriate actions. Typically, there are two types of actions, thatare, to reply or relay in capsules through the networks, or to notify the users regarding the incoming capsule. •Capsule : An active application may contain several capsule types. Each of them carries program code (also referred to as forwarding routine). Since the application defines a protocol to specify the interactions among capsules as well as the application stubs. Every capsule executes its forwarding routine at each router it visits along the path between the source and destination.•Active Service Base : An active service base is designed to export routers’ environments’ services and execute program calls from application stubs and capsules from different EEs. The base is loaded automatically at each router whenever a capsule arrives.The interactions among components within ANSP are shown in Figure 3. The designs of some key components in the ANSP will be discussed in the following subsections. A. Capsule (ANSPCapsule)ANSPXdr decode () ANSPXdr encode () int length ()Boolean execute ()New types of capsule are created by extending the abstract class ANSPCapsule . New extensions are required to define their own forwarding routines as well as their serialization procedures. These methods are indicated below:The execution of a capsule in ANSP is listed below. It is similar to the process in ANTS.1. A capsule is in serial binary representation before it issent to the network. When an active router receives a byte sequence, it invokes decode() to convert the sequence into a capsule. 2. The router invokes the forwarding routine of thecapsule, execute(). 3. When the capsule has finished its job and forwardsitself to its next hop by calling send(), this call implicitly invokes encode() to convert the capsule into a new serial byte representation. length() isused inside the call of encode() to determine the length of the resulting byte sequence. ANSP provides a XDR library called ANSPXdr to ease the jobs of encoding and decoding.B. Active Service Base (ANSPBase)In an active node, the Active Service Base provides a unified interface to export the available resources in EEs for the rest of the ANSP components. The services may include thread management, node query, and soft-store operation, as shown in Table 1.TABLE I. ACTIVE SERVICE BASE FUNCTION CALLSFunction Definition Descriptionboolean send (Capsule, Address) Transmit a capsule towards its destination using the routing table of theunderlying environment.ANSPAddress getLocalHost () Return address of the local host as an ANSPAddress structure. This isuseful when a capsule wants to check its current location.boolean isLocal (ANSPAddress) Return true if its input argument matches the local host’s address andreturn false otherwise.createThread () Create a new thread that is a class ofANSPThreadInterface (discussed later in Section VIA “Unified Thread Abstraction”).putSStore (key, Object) Object getSStore (key) removeSStore (key)The soft-store operations are provided by putSStore(), getSSTore(), and removeSStore(), and they put, retrieve, and remove data respectively. forName (PathName) Supported in ANSP to retrieve a classobject corresponding to the given path name in its argument. This code retrieval may rely on the code loading mechanism in the environment whennecessary.C. Application Client (ANSPClient)boolean start (args[])boolean start (args[],runningEEs) boolean start (args[],startClient)boolean start (args[],startClient, runningEE)Application Client is an interface between users and the nearby active source router. It does the following responsibilities.1. Code registration: It may be necessary to specify thelocation and name of the application code in some execution environments, e.g., ANTS. 2. Application initialization: It includes selecting anexecution environment to execute the application among those are available at the source router. Each active application can create an application client instance by extending the abstract class, ANSPClient . The extension inherits a method, start(), to automatically handle both the registration and initialization processes. All overloaded versions of start() accept a list of arguments, args , that are passed to the application stub during its initialization. An optional argument called runningEEs allows an application client to select a particular set of environment variables, specified by a list of standardized numerical environment ID, the ANEP ID, to perform code registration. If this argument is not specified, the default setting can only include ANTS and ASP. D. Application Stub (ANSPApplication)receive (ANSPCapsule)Application stubs reside at the source and destination routers to initialize the ANSP application after the application clients complete the initialization and registration processes. It is responsible for receiving and serving capsules from the networks as well as actions requested from the clients. A new instance is created by extending the application client abstract class, ANSPApplication . This extension includes the definition of a handling routine called receive(), which is invoked when a stub receives a new capsule.IV. ANSP E XAMPLE : T RACE -R OUTEA testbed has been created to verify the design correctnessof ANSP in heterogeneous environments. There are three types of router setting on this testbed:1. Router that contains ANTS and a ANSP daemonrunning on behalf of ASP; 2. Router that contains ASP and a ANSP daemon thatruns on behalf of ANTS; 3. Router that contains both ASP and ANTS.The prototype is written in Java [11] with a traceroute testing program. The program records the execution environments of all intermediate routers that it has visited between the source and destination. It also measures the RTT between them. Figure 4 shows the GUI from the application client, and it finds three execution environments along the path: ASP, ANTS, and ASP. The execution sequence of the traceroute program is shown in Figure 5.Figure 4. The GUI for the TRACEROUTE Program.The TraceCapsule program code is created byextending the ANSPCapsule abstract class. When execute() starts, it checks the Boolean value of returning to determine if it is returning from the destination. It is set to true if TraceCapsule is traveling back to the source router; otherwise it is false . When traveling towards the destination, TraceCapsule keeps track of the environments and addresses of the routers it has visited in two arrays, path and trace , respectively. When it arrives at a new router, it calls addHop() to append the router address and its environment to these two arrays. When it finally arrives at the destination, it sets returning to false and forwards itself back to the source by calling send().When it returns to source, it invokes deliverToApp() to deliver itself to the application stub that has been running at the source. TraceCapsule carries information in its data field through the networks by executing encode() and decode(), which encapsulates and de-capsulates its data using External Data Representation (XDR) respectively. The syntax of ANSP XDR follows the syntax of XDR library from ANTS. length() in TraceCapsule returns the data length, or it can be calculated by using the primitive types in the XDRlibrary.Figure 5. Flow of the TRACEROUTE Capsules.V. C ONCLUSIONSIn this paper, we present a new unified layered architecture for active networks. The new model is known as Active Network Socket Programming (ANSP). It allows each active application to be written once and run on multiple environments in active networks. Our experiments successfully verify the design of ANSP architecture, and it has been successfully deployed to work harmoniously with ANTS and ASP without making any changes to their architectures. In fact, the unified programming interface layer is light-weighted and can be dynamically deployable upon request.R EFERENCES[1] D.D. Clark, D.L. Tennenhouse, “Architectural Considerations for a NewGeneration of Protocols,” in Proc. ACM Sigcomm’90, pp.200-208, 1990. [2] D. Tennenhouse, J. M. Smith, W. D. Sicoskie, D. J. Wetherall, and G. J.Minden, “A survey of active network research,” IEEE Communications Magazine , pp. 80-86, Jan 1997.[3] D. Wetherall, U. Legedza, and J. Guttag, “Introducing new internetservices: Why and how,” IEEE Network Magazine, July/August 1998. [4] M. Fry, A. Ghosh, “Application Layer Active Networking,” in ComputerNetworks , Vol.31, No.7, pp.655-667, 1999.[5] K. W. Chin, “An Investigation into The Application of Active Networksto Mobile Computing Environments”, Curtin University of Technology, March 2000.[6] S. Bhattacharjee, K. L. Calvert, and E. W. Zegura, “Self OrganizingWide-Area Network Caches”, Proc. IEEE INFOCOM ’98, San Francisco, CA, 29 March-2 April 1998.[7] L. H. Leman, S. J. Garland, and D. L. Tennenhouse, “Active ReliableMulticast”, Proc. IEEE INFOCOM ’98, San Francisco, CA, 29 March-2 April 1998.[8] D. Descasper, G. Parulkar, B. Plattner, “A Scalable, High PerformanceActive Network Node”, In IEEE Network, January/February 1999.[9] E. L. Nygren, S. J. Garland, and M. F. Kaashoek, “PAN: a high-performance active network node supporting multiple mobile code system”, In the Proceedings of the 2nd IEEE Conference on Open Architectures and Network Programming (OpenArch ’99), March 1999. [10] D. L. Tennenhouse, and D. J. Wetherall. “Towards an Active NetworkArchitecture”, In Proceeding of Multimedia Computing and Networking , January 1996.[11] D. J. Wetherall, J. V. Guttag, D. L. Tennenhouse, “ANTS: A toolkit forBuilding and Dynamically Deploying Network Protocols”, Open Architectures and Network Programming, 1998 IEEE , 1998 , Page(s): 117 –129.[12] B. Braden, A. Cerpa, T. Faber, B. Lindell, G. Phillips, and J. Kann.“Introduction to the ASP Execution Environment”: /active-signal/ARP/index.html .[13] “The java language: A white paper,” Tech. Rep., Sun Microsystems,1998.。
本科毕业设计外文翻译(中文)

本科生毕业设计(论文)外文翻译外文原文题目:Real-time interactive optical micromanipulation of a mixture of high- and low-index particles中文翻译题目:高低折射率微粒混合物的实时交互式光学微操作毕业设计(论文)题目:阵列光镊软件控制系统设计姓名:任有健学院:生命学院班级:06210501指导教师:李勤高低折射率微粒混合物的实时交互式光学微操作Peter John Rodrigo Vincent Ricardo Daria Jesper Glückstad丹麦罗斯基勒DK-4000号,Risø国家实验室光学和等离子研究系jesper.gluckstad@risoe.dkhttp://www.risoe.dk/ofd/competence/ppo.htm摘要:本文论证一种对于胶体的实时交互式光学微操作的方法,胶体中包含两种折射率的微粒,与悬浮介质(0n )相比,分别低于(0L n n <)、高于(0H n n >)悬浮介质的折射率。
球形的高低折射率微粒在横平板上被一批捕获激光束生成的约束光势能捕获,捕获激光束的横剖面可以分为“礼帽形”和“圆环形”两种光强剖面。
这种应用方法在光学捕获的空间分布和个体几何学方面提供了广泛的可重构性。
我们以实验为基础证实了同时捕获又独立操作悬浮于水(0 1.33n =)中不同尺寸的球形碳酸钠微壳( 1.2L n ≈)和聚苯乙烯微珠( 1.57H n =)的独特性质。
©2004 美国光学学会光学分类与标引体系编码:(140.7010)捕获、(170.4520)光学限制与操作和(230.6120)空间光调制器。
1 引言光带有动量和角动量。
伴随于光与物质相互作用的动量转移为我们提供了在介观量级捕获和操作微粒的方法。
过去数十年中的巨大发展已经导致了在生物和物理领域常规光学捕获的各种应用以及下一代光学微操作体系的出现[1-5]。
办公楼毕业设计英文翻译(外文翻译)

办公楼毕业设计英文翻译(外文翻译)原文:The future of the tall buildingAnd structure of buildingsZoning effects on the density of tall buildings and solar design may raise ethical challenge.A combined project of old and new buildings may bring back human scale to our cities. Owners and conceptual designers will be challenged in the 1980s to produce economically sound, people-oriented buildings.In 1980 the Level House, designed by Skidmore, Owings and Merril1 (SOM) received the 25-year award from the American Institut e of Architects “in recognition of architectural design of enduring significance”. This award is given once a year for a building between 25and 35 years old .Lewis Mumford described the Lever House as “the first office building in which modern materials, m odern construction, modern functions have been combined with a modern plan”. At the time, this daring concept could only be achieved by visionary men like Gordon Bunshaft , the designer , and Charles Luckman , the owner and then-president of Lever Brothers . The project also included a few “first” : (1) it was the first sealed glass tower ever built ; (2) it was the first office building designed by SOM ;and (3) it was the first office building on Park Avenue to omit retail space on the first floor. Today, after hundreds of look-alike and variations on the grid design, we have reached what may be the epitome of tall building design: the nondescript building. Except for a few recently completed buildings that seem to be people-oriented in their lower floors, most tall buildings seem to be a repletion of the dull, graph-paper-like monoliths in many of our cities. Can this be the end of the design-line for tall buildings? Probably not. There are definite signs that are most encouraging. Architects and owners have recently begun to discuss the design problem publicly. Perhaps we are at the threshold of a new era. The 1980s may bring forth some new visionaries like Bunshaft and Luckman. If so, what kinds of restrictions or challenges do they face?译文:高层建筑展望及建筑结构区域规划对高层建筑物的密度和对自然采光设计可能引起道德问题将产生影响。
机械设计制造及其自动化毕业设计外文翻译

英文原文名Automatic production line PLC control中文译文:自动化生产线自动上料站的PLC控制自动生产线是由工件传送系统和控制系统,将一组自动机床和辅助设备按照工艺顺序联结起来,自动完成产品全部或部分制造过程的生产系统,简称自动线。
二十世纪20年代,随着汽车、滚动轴承、小电机和缝纫机和其他工业发展,机械制造业开始出现在自动生产线,第一个是组合机床自动线。
在20世纪20年代,第一次出现在汽车工业流水生产线和半自动生产线,然后发展成自动生产线。
第二次世界大战后,在机械制造工业发达国家,自动生产线的数量急剧增加。
采用自动生产线生产的产品应该足够大,产品设计和技术应该是先进的、稳定的和可靠的,基本上保持了很长一段时间维持不变。
自动线用于大,大规模生产可以提高劳动生产率,稳定和提高产品质量,改善劳动条件,降低生产区域,降低生产成本,缩短生产周期,保证生产平衡、显著的经济效益。
自动生产线的一个干预指定的程序或命令自动操作或控制的过程,我们的目标是稳定、准确、快速。
自动化技术广泛用于工业、农业、军事、科学研究、交通运输、商业、医疗、服务和家庭,等自动化生产线不仅可以使人们从繁重的体力劳动、部分脑力劳动以及恶劣、危险的工作环境,能扩大人的器官功能,极大地提高劳动生产率,提高人们认识世界的能力,可以改变世界。
下面我说下它的应用范围:机械制造业中有铸造、锻造、冲压、热处理、焊接、切削加工和机械装配等自动线,也有包括不同性质的工序,如毛坯制造、加工、装配、检验和包装等的综合自动线。
加工自动线发展最快,应用最广泛的机械制造。
主要包括:用于处理盒、外壳、各种各样的部件,如组合机床自动线;用于加工轴、盘部分,由通用、专业化、或自动机器自动专线;转子加工自动线;转子自动线加工过程简单、小零件等。
1.确保节拍时间:无论什么样的产品,都必须完成的时间生产。
2.单元过程:只有一个产品,单位部分处理、组装、加工和材料。
本科毕业设计外文文献翻译

(Shear wall st ructural design ofh igh-lev el fr ameworkWu Jiche ngAbstract : In t his pape r the basic c oncepts of man pow er from th e fra me sh ear w all str uc ture, analy sis of the struct ur al des ign of th e c ont ent of t he fr ame she ar wall, in cludi ng the seism ic wa ll she ar spa本科毕业设计外文文献翻译学校代码: 10128学 号:题 目:Shear wall structural design of high-level framework 学生姓名: 学 院:土木工程学院 系 别:建筑工程系 专 业:土木工程专业(建筑工程方向) 班 级:土木08-(5)班 指导教师: (副教授)nratiodesign, and a concretestructure in themost co mmonly usedframe shear wallstructurethedesign of p oints to note.Keywords: concrete; frameshearwall structure;high-risebuildingsThe wall is amodern high-rise buildings is an impo rtant buildingcontent, the size of theframe shear wall must comply with building regulations. The principle is that the largersizebut the thicknessmust besmaller geometric featuresshouldbe presented to the plate,the force is close to cylindrical.The wall shear wa ll structure is a flatcomponent. Itsexposure to the force along the plane level of therole ofshear and moment, must also take intoaccountthe vertical pressure.Operate under thecombined action ofbending moments and axial force andshear forcebythe cantilever deep beam under the action of the force levelto loo kinto the bottom mounted on the basis of. Shearwall isdividedinto a whole walland theassociated shear wall in theactual project,a wholewallfor exampl e, such as generalhousingconstruction in the gableor fish bone structure filmwalls and small openingswall.Coupled Shear walls are connected bythecoupling beam shear wall.Butbecause thegeneralcoupling beamstiffness is less thanthe wall stiffnessof the limbs,so. Walllimb aloneis obvious.The central beam of theinflection pointtopay attentionto thewall pressure than the limits of the limb axis. Will forma shortwide beams,widecolumn wall limbshear wall openings toolarge component atbothen ds with just the domain of variable cross-section ro din the internalforcesunder theactionof many Walllimb inflection point Therefore, the calcula tions and construction shouldAccordingtoapproximate the framestructure to consider.The designof shear walls shouldbe based on the characteristics of avariety ofwall itself,and differentmechanical ch aracteristicsand requirements,wall oftheinternalforcedistribution and failuremodes of specific and comprehensive consideration of the design reinforcement and structural measures. Frame shear wall structure design is to consider the structure of the overall analysis for both directionsofthehorizontal and verticaleffects. Obtain theinternal force is required in accordancewiththe bias or partial pull normal section forcecalculation.The wall structure oftheframe shear wall structural design of the content frame high-rise buildings, in the actual projectintheuse of themost seismic walls have sufficient quantitiesto meet thelimitsof the layer displacement, the location isrelatively flexible. Seismic wall for continuous layout,full-length through.Should bedesigned to avoid the wall mutations in limb length and alignment is notupand down the hole. The sametime.The inside of the hole marginscolumnshould not belessthan300mm inordertoguaranteethelengthof the column as the edgeof the component and constraint edgecomponents.Thebi-direc tional lateral force resisting structural form of vertical andhorizontalwallconnected.Each other as the affinityof the shear wall. For one, two seismic frame she ar walls,even beam highratio should notgreaterthan 5 and a height of not less than400mm.Midline columnand beams,wall midline shouldnotbe greater tha nthe columnwidthof1/4,in order toreduce thetorsional effect of the seismicaction onthecolumn.Otherwisecan be taken tostrengthen thestirrupratio inthe column tomake up.If theshear wall shearspan thanthe big two. Eventhe beamcro ss-height ratiogreaterthan 2.5, then the design pressure of thecut shouldnotmakeabig 0.2. However, if the shearwallshear spanratioof less than two couplingbeams span of less than 2.5, then the shear compres sion ratiois notgreater than 0.15. Theother hand,the bottom ofthe frame shear wallstructure to enhance thedesign should notbe less than200mmand notlessthanstorey 1/16,otherpartsshouldnot be less than 160mm and not less thanstorey 1/20. Aroundthe wall of the frame shear wall structure shouldbe set to the beam or dark beamand the side columntoform a border. Horizontal distributionofshear walls can from the shear effect,this design when building higher longeror framestructure reinforcement should be appropriatelyincreased, especially in the sensitiveparts of the beam position or temperature, stiffnesschange is bestappropriately increased, thenconsideration shouldbe givento the wallverticalreinforcement,because it is mainly from the bending effect, andtake in some multi-storeyshearwall structurereinforcedreinforcement rate -likelessconstrained edgeofthecomponent or components reinforcement of theedge component.References: [1 sad Hayashi,He Yaming. On the shortshear wall high-rise buildingdesign [J].Keyuan, 2008, (O2).高层框架剪力墙结构设计吴继成摘要: 本文从框架剪力墙结构设计的基本概念人手, 分析了框架剪力墙的构造设计内容, 包括抗震墙、剪跨比等的设计, 并出混凝土结构中最常用的框架剪力墙结构设计的注意要点。
本科毕业设计(论文)外文翻译

重金属污染存在于很多工业的废水中,如电镀,采矿,和制革。
2.实验
2.1化学药剂
本实验所使用的药剂均为分析纯,如无特别说明均购买自日本片山化工。铅离子储备液通过溶解Pb(NO3)2配制,使用时稀释到需要的浓度。HEPES缓冲液购买自Sigma–Aldrich。5 mol/L的HCl和NaOH用来调整pH。
附5
华南理工大学
本科毕业设计(论文)翻译
班级2011环境工程一班
姓名陈光耀
学号201130720022
指导教师韦朝海
填表日期
中文译名
(1)巯基改性纤维素对葡萄糖溶液中铅的吸附(2)黄原酸化橘子皮应用于吸附水中的铅离子
外文原文名
(1)Adsorption of Pb(II) from glucose solution on thiol-functionalized cellulosic biomass
2.5分析方法
铅离子的浓度用分光光度计在616 nm波长处用铅与偶氮氯膦-III络合物进行分析。葡萄糖含量采用苯酚—硫酸分光光度法测定。所有的实验均进行三次,已经考虑好误差。
3.结果和讨论
3.1FTIR分析和改性脱脂棉对铅(II)的吸附机制
图1是脱脂棉、改性脱脂棉在400-4000 cm-1(A)和2540-2560 cm-1(B)范围内的红外光谱图。可以看出,改性后改性脱脂棉的红外光谱图中在1735.71 cm-1处出现了一个新的吸收峰是酯基C=O的拉伸振动峰,可见改性脱脂棉中已经成功引入巯基官能团。同时,在2550.52 cm-1出现的一个新吸收峰代表的是S-H官能团的弱吸收峰,更深一层的证明了巯基已经嫁接到脱脂棉上。图1(b)是2540-2560 cm-1光谱范围的一个放大图像,可以清楚的观察到S-H官能团的弱吸收峰。进一步证明了酯化改性脱脂棉引入巯基是成功的。而从吸附后的曲线可以看到,2550.52cm-1处S-H的吸收峰消失,证明了硫原子和Pb(II)络合物的形成,同时1735.71cm-1处C=O的吸收峰强度看起来有轻微的减弱可能也是和Pb(II)的络合吸附有关。
软件工程专业毕业设计外文文献翻译

软件工程专业毕业设计外文文献翻译1000字本文将就软件工程专业毕业设计的外文文献进行翻译,能够为相关考生提供一定的参考。
外文文献1: Software Engineering Practices in Industry: A Case StudyAbstractThis paper reports a case study of software engineering practices in industry. The study was conducted with a large US software development company that produces software for aerospace and medical applications. The study investigated the company’s software development process, practices, and techniques that lead to the production of quality software. The software engineering practices were identified through a survey questionnaire and a series of interviews with the company’s software development managers, software engineers, and testers. The research found that the company has a well-defined software development process, which is based on the Capability Maturity Model Integration (CMMI). The company follows a set of software engineering practices that ensure quality, reliability, and maintainability of the software products. The findings of this study provide a valuable insight into the software engineering practices used in industry and can be used to guide software engineering education and practice in academia.IntroductionSoftware engineering is the discipline of designing, developing, testing, and maintaining software products. There are a number of software engineering practices that are used in industry to ensure that software products are of high quality, reliable, and maintainable. These practices include software development processes, software configuration management, software testing, requirements engineering, and project management. Software engineeringpractices have evolved over the years as a result of the growth of the software industry and the increasing demands for high-quality software products. The software industry has developed a number of software development models, such as the Capability Maturity Model Integration (CMMI), which provides a framework for software development organizations to improve their software development processes and practices.This paper reports a case study of software engineering practices in industry. The study was conducted with a large US software development company that produces software for aerospace and medical applications. The objective of the study was to identify the software engineering practices used by the company and to investigate how these practices contribute to the production of quality software.Research MethodologyThe case study was conducted with a large US software development company that produces software for aerospace and medical applications. The study was conducted over a period of six months, during which a survey questionnaire was administered to the company’s software development managers, software engineers, and testers. In addition, a series of interviews were conducted with the company’s software development managers, software engineers, and testers to gain a deeper understanding of the software engineering practices used by the company. The survey questionnaire and the interview questions were designed to investigate the software engineering practices used by the company in relation to software development processes, software configuration management, software testing, requirements engineering, and project management.FindingsThe research found that the company has a well-defined software development process, which is based on the Capability Maturity Model Integration (CMMI). The company’s software development process consists of five levels of maturity, starting with an ad hoc process (Level 1) and progressing to a fully defined and optimized process (Level 5). The company has achieved Level 3 maturity in its software development process. The company follows a set of software engineering practices that ensure quality, reliability, and maintainability of the software products. The software engineering practices used by the company include:Software Configuration Management (SCM): The company uses SCM tools to manage software code, documentation, and other artifacts. The company follows a branching and merging strategy to manage changes to the software code.Software Testing: The company has adopted a formal testing approach that includes unit testing, integration testing, system testing, and acceptance testing. The testing process is automated where possible, and the company uses a range of testing tools.Requirements Engineering: The company has a well-defined requirements engineering process, which includes requirements capture, analysis, specification, and validation. The company uses a range of tools, including use case modeling, to capture and analyze requirements.Project Management: The company has a well-defined project management process that includes project planning, scheduling, monitoring, and control. The company uses a range of tools to support project management, including project management software, which is used to track project progress.ConclusionThis paper has reported a case study of software engineering practices in industry. The study was conducted with a large US software development company that produces software for aerospace and medical applications. The study investigated the company’s software development process,practices, and techniques that lead to the production of quality software. The research found that the company has a well-defined software development process, which is based on the Capability Maturity Model Integration (CMMI). The company uses a set of software engineering practices that ensure quality, reliability, and maintainability of the software products. The findings of this study provide a valuable insight into the software engineering practices used in industry and can be used to guide software engineering education and practice in academia.外文文献2: Agile Software Development: Principles, Patterns, and PracticesAbstractAgile software development is a set of values, principles, and practices for developing software. The Agile Manifesto represents the values and principles of the agile approach. The manifesto emphasizes the importance of individuals and interactions, working software, customer collaboration, and responding to change. Agile software development practices include iterative development, test-driven development, continuous integration, and frequent releases. This paper presents an overview of agile software development, including its principles, patterns, and practices. The paper also discusses the benefits and challenges of agile software development.IntroductionAgile software development is a set of values, principles, and practices for developing software. Agile software development is based on the Agile Manifesto, which represents the values and principles of the agile approach. The manifesto emphasizes the importance of individuals and interactions, working software, customer collaboration, and responding to change. Agile software development practices include iterative development, test-driven development, continuous integration, and frequent releases.Agile Software Development PrinciplesAgile software development is based on a set of principles. These principles are:Customer satisfaction through early and continuous delivery of useful software.Welcome changing requirements, even late in development. Agile processes harness change for the customer's competitive advantage.Deliver working software frequently, with a preference for the shorter timescale.Collaboration between the business stakeholders and developers throughout the project.Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done.The most efficient and effective method of conveying information to and within a development team is face-to-face conversation.Working software is the primary measure of progress.Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely.Continuous attention to technical excellence and good design enhances agility.Simplicity – the art of maximizing the amount of work not done – is essential.The best architectures, requirements, and designs emerge from self-organizing teams.Agile Software Development PatternsAgile software development patterns are reusable solutions to common software development problems. The following are some typical agile software development patterns:The Single Responsibility Principle (SRP)The Open/Closed Principle (OCP)The Liskov Substitution Principle (LSP)The Dependency Inversion Principle (DIP)The Interface Segregation Principle (ISP)The Model-View-Controller (MVC) PatternThe Observer PatternThe Strategy PatternThe Factory Method PatternAgile Software Development PracticesAgile software development practices are a set ofactivities and techniques used in agile software development. The following are some typical agile software development practices:Iterative DevelopmentTest-Driven Development (TDD)Continuous IntegrationRefactoringPair ProgrammingAgile Software Development Benefits and ChallengesAgile software development has many benefits, including:Increased customer satisfactionIncreased qualityIncreased productivityIncreased flexibilityIncreased visibilityReduced riskAgile software development also has some challenges, including:Requires discipline and trainingRequires an experienced teamRequires good communicationRequires a supportive management cultureConclusionAgile software development is a set of values, principles, and practices for developing software. Agile software development is based on the Agile Manifesto, which represents the values and principles of the agile approach. Agile software development practices include iterative development, test-driven development, continuous integration, and frequent releases. Agile software development has many benefits, including increased customer satisfaction, increased quality, increased productivity, increased flexibility, increased visibility, and reduced risk. Agile software development also has some challenges, including the requirement for discipline and training, the requirement for an experienced team, the requirement for good communication, and the requirement for a supportive management culture.。
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毕业设计(论文)外文资料翻译学院:电子工程学院专业级:电子信息工程D电子091学生姓名:环洲书院学号:510920138指导教师:韩晓春(高级实验师)2008International Conference on 外文出处:MultiMedia and Information Technology 附件: 1.外文资料翻译译文; 2.外文原文指导教师评语:签名:年月日图像采集技术与AVR单片机摘要图像采集系统在各种数字图像应用系统中是不可或缺的部分。
在本文中,我们开发了一种基于AVR单片机的紧凑的图像采集与处理系统。
该系统主要利用AVR单片机ATmega16与低功耗、高性能的数据处理主控制单元。
首先,它完成了CMOS光通过I2C接口接收的相机模块C3088初始化。
然后,它被用来从LCD 上实时显示C3088和获取图像的采集状态。
最后,利用单片机串行通信接口发送数据到电脑,在经过数据处理显示图像。
硬件电路和软件系统的设计。
关键词:图像采集,单片机,AVR串行通信,视频监控一、简介随着社会的进步和科学的发展,技术与经济,要求更安全的工作和生活环境所倡导的组织和个人对防盗措施都提出了新的要求。
作为一个有效的安全保护手段,在视频监控领域中发挥着重要的作用,公共安全等,已经越来越受到广泛关注[1-4]。
目前,视频监督和控制已经进入所有域名,我们几乎每天可以看到它的应用。
图像采集系统在各种数字图像应用系统中是不可或缺的部分。
AVR单片机是基于可编程GSI和计算机技术的大规模集成电路芯片(5-9]。
它的快速数据采集和处理功能以及各种功能模块集成在芯片中在各种场合提供丰富便捷的应用程序。
比较CCD、CMOS图像传感器可以将时间序列处理成电路,前端放大器的图像信号和数字部分为一个芯片,因此它的发展是高度强调由行业一向性。
目前,随着技术的发展,噪声的CMOS图像传感器已经有效地改善,并且解决能力明显增强。
CMOS图像传感器由于其低廉的价格,图像质量,高整合度和相对较少的电力消耗将被广泛应用在视频采集领域。
因此,在本文中,我们开发实施的图像数据采集系统是基于AVR单片机的。
程序驱动摄影机C3088[10]通过单片机ATmega16获取原始图像数据,通过I2C接口的初始化摄像头协议,并实现数据传输,。
该电路具有许多优点如结构简单,方便转移和低CPU占用,它可以降低系统的总成本。
二、系统结构它以数字化和自动化的水准在传统光学采集系统中安装电气部分数据处理。
数据处理单元的原则包括快速数据运算速度,丰富的外围接口和低功耗。
根据这些原则,我们采用AVR单片机与高性能的设计,它可以结合获取的信息数据采集仪在CMOS图像传感器前端显示,其结构示意图见图1。
该系统采用单片机作为微控制器,驱动摄像头通过I2C总线,主要是初始化一些寄存器,组成了图像传感器。
当初始化完成时,相机输出三个符号包括像素时钟信号同步信号和垂直,生的同步信号。
单片机读取原始数据的图像并从相机数据总线通过测试这三个标志信号,暂时存储数据到数据存储器在单片机,然后传输数据到计算机通过串行通信。
图1.系统结构硬件选择器在硬件的实现方面对于系统的整体性能是非常重要的。
我们可以选择单片机具有较高的性价比和速度,我们也可以选择功能强大的DSP,速度快,多个接口和核心芯片,我们也可以选择ARM微处理器。
作为视频采集系统、图像系统中使用的传感器的速度可以由单片机控制。
当我们第一次用51系列单芯片微型计算机在设计过程中,我们发现它无法满足数据庞大的吞吐量所需的视频采集。
所以我们使用ATmega16系统中可以满足设计要求的系统。
单片机被广泛应用于爱特梅尔公司的许多领域如工业生产控制、智能仪器、数据采集和家用电器。
这种单片机具有RISC结构。
由于其先进的指令集和单时钟周期指令执行时间。
当它工作达到16MIPS16兆赫时,它可以减少能耗之间的冲突加快处理速度。
执行一个指令只需要一个时钟周期,且速度比传统的单片机快很多,所以它可以胜任高速条件下的A/D采样的控制。
但当我们使用DSP,ARM和FPGA/CPLD,它会浪费资源,使系统变得越来越复杂,成本和性能是不合理的。
用于视频捕获设备,无论是CCD或CMOS全部采用光接收元件作为捕获图像的基本措施。
核心的CCD/CMOS光接收组件是一个光接收二极管,产生输出电流时,接收光的照射。
电流的强度对应光的照射强度。
对于周边设备,光接收元件CCD与光接收元件不同,除了光接收二极管。
光接收的前部分还包括一个存储单元,用于控制相邻电荷。
光接收二极管占多数的面积,即有效的受光面积,CCD光接收组件更大,它可以在相同的条件下获得更强的光信号,并使输出相应的电信号更清楚。
由于CMOS图像传感器技术发展很快,每一个光接收元件可以直接集成在CMOS传感器放大器并完成逻辑模数转换。
当光接收二极管接收光的照射而产生的模拟电信号,并模拟电信号放大在光接收元件之前转换成相应的数字信号。
换句话说,在CMOS传感器,每个光接收组件产品都有最终的数字输出。
由于集成度高,体积小,使用方便,内容丰富,图像捕获快速,我们采用CMOS传感器组成的相机模块C3088(OV6620)作为设计的采集设备。
默认的分辨率的摄像头是356×292,所以它非常适合于单芯片微型计算机的操作能力。
该相机模块C3088工作电压为5V,它的引脚20和引脚22与电源连接,和引脚31连接数字地球,与引脚21,引脚15和引脚17连接模拟地球。
数据线连接~Y0Y7PA0~PA7单片机的数据线,和uv0~uv7连接PB0~PB7的单片机,和PCLK与PD2,和超链接与PD3,和垂直同步连接PD4。
SDA和SCL与PC1,接PC0。
现场可编程逻辑器件包括356×292分辨率的图像阵列,模拟信号处理器,双8位模拟数字转换,模拟视频多路转接器,数字格式输出端口,一个模拟视频接口,I2C总线接口及寄存器。
该传感器采用基于完整图像的电子曝光控制算法。
单片机采用RS232串行通信与上位计算机的通信。
其电路结构是非常简单的,它可以保证系统的稳定和满足系统设计要求。
该系统采用RS232连接计算机和视频数据传输。
ATmega16采用8位数据位,1位停止位和0个奇偶校验位,其速度可以达到230400bps,和计算机的串行端口速度仅为115200bps,可以满足系统的设计要求。
由于单片机的电压ttl5v和RS232电压12V,双方需要进行电平转换来识别。
该系统需要与单片机通过MAX232芯片如图2所示连接。
图2.电压匹配电路显示的液晶采用ZT018智能全彩液晶。
这个模块具有基本的绘图功能,采用通常的微型客车作为接口,因此它可以节省开发时间以及方便发展和转移。
它的接口模式包括SPI和I2C,本系统采用I2C接口,只需要两个数据行。
四、软件C3088由CMOS图像传感器OV6620,它的初始化主要取决于通过I2C对内部寄存器的写入操作。
通过软件的初始化设置,视频数字输出可以使用不同的格式并和其他寄存器进行初始化。
因为最初的时钟频率的C3088相机模块是17.73mhz,当它工作在16位数据输出模式,其PCLK时钟周期是112ns和当它工作在8位数据输出模式,其PCLK时钟周期是56ns。
晶体振荡所采用的单片机是16兆赫和单周期是62.5ns。
所以单片机可以不遵循视频的速度。
它必须通过写寄存器0x11降低时钟频率PCLK,设置低5位的寄存器在“1”可以减少PCLK 至69.25千赫,可以适合单片机处理较低的速度。
数据输出格式通常的CMOS图像传感器是原始数据输出格式。
由于CMOS 光传感器单元具有三种颜色不同的响应灵敏度,响应是非线性的。
它是相对于亮度,加上材料。
因此,图像传感器的原始数据应校正和补偿。
不同厂家的产品补偿曲线是不同的,所以我们应该设计不同的补偿算法。
现场可编程逻辑器件不仅可以输出的原始数据格式的R,G和B,并将色彩补偿算法在芯片中,并能输出YUV和YCrCb视频输出格式符合CCIR601标准。
相机通过初始化工作在最低频率。
单片机可将数据存储在单片机数据存储器时,它读取原始数据,并将所获得的程序转换为BMP格式的数据,并将数据传送给计算机进行存储和显示。
串行通信是一种通信模式,可以通过比特传输二进制数据,因此传输线所需要的是很少的数量,这是非常适合的分级控制系统,分层控制系统,分布式控制系统和远程通信。
由于分布式控制系统被广泛应用在现代的计算机控制系统,因此它往往需要一个主计算机控制多台下位机,与计算机和单片机成为一个重要的问题之间的通信。
单芯片的微型计算机的程序流程图如图3所示。
计算机程序流程图如图4所示。
图3.程序流程图的数据采集和发送图4.程序流程图的数据接收和处理五、结论视频数据的采集和存储技术日复一日发展很快,识别技术,数字电视和实时监测和控制的行业前景很好。
相机的图像采集系统基于AVR单片机和C3088简化了系统的结构。
该系统具有清晰的图像,可满足实时显示的要求,可广泛应用于工业自动化监控网络视频。
Image Acquisition Technology with AVR Single Chip MicrocomputerXiao ChenDepartment of Electronic Information Engineering,Nanjing University of Information Science and TechnologyNanjing210044,Chinarainofsun@Abstract—The image acquisition system is one of indispensable parts in various kinds of digital image application system.In this article,we developed a sort of video camera compact image acquisition and processing system based on AVR single chip microcomputer.The system utilises AVR single chip microcomputer ATmega16with low power consumption and high performance as the data processing main control unit.Firstly,it completes the initialisation of CMOS light-receiving camera module C3088through I2C interface.Then it is used to acquire image from C3088and the acquisition states are displayed on LCD real time.Finally,the single chip microcomputer utilises serial communication interface to send data to the computer, which displays the image after data processing.The hardware circuit and the software programs of the system are designed.Keywords-Image acquisition;single chip microcomputer;AVR;serial communication; video surveillanceI.INTRODUCTIONWith the progress of society and the development of science,technology and economy,the demands for more security in working and living environment has been advocated by both organizations and individuals,which puts forward new requirements for anti-theft measures.As an effective means of security protection, video monitoring plays an important role in fields of public security,etc.,and has drawn increasing and extensive attentions[1-4].At present,Video supervision and control has entered into all domains,and we can see its applications almost everyday. The image acquisition system is one of indispensable parts in various kinds of digital image application system.AVR single chip microcomputer is the integrated chip based on programmable GSI and computer technology[5-9].Its quick data acquisition and processing function and various function modules integrated in the chip offer abundant conveniences for its applications in various paring with CCD,the CMOS image sensor could integrate the time sequence processing circuit,the front-end amplifier of image signals and digital part into one chip,so its development is highly emphasised by the industry all along.At present,with the development of technology and technique,the yawp of CMOS image sensor has been improved effectively and its resolving capability has been obviously enhanced.CMOS image sensor will be extensively applied in the video acquisition domain because of its cheap price,applied image quality,high integration degree and relatively little power consumption.Therefore,in this article,we develop the implementation program of video data acquisition systembased on A VR single chip microcomputer.The program drives the camera C3088[10] through single chip microcomputer ATmega16to obtain the original image data acquired by the camera,and implement data transmission and initialisation of camera through I2C interface protocol.This circuit has many advantages such as simple structure,convenient transfer and low CPU occupation rate,and it can reduce the total cost of the System.II.SYSTEM STRUCTUREIt can realize the digitalization and automatization of leveling to install the electric parts of data process in traditional optical acquisition system.The principles of data processing unit include quick data operation speed,abundant peripheral interfaces and low power consumption.According to these principles,we adopt AVR single chip microcomputer with high performance in the design,which can combine with the information acquired by the data acquisition apparatus CMOS image sensor in the front end,and its structure sketch is seen in Fig.1.The system adopt single chip microcomputer as the micro-controller to drive the camera through I2C bus,which mainly initializes some registers which composes the image sensor of the camera.When the initialization of camera is completed,the camera outputs three symbol signals including pixel clock,raw synchronous signal and vertical synchronous signal.The single chip microcomputer read the original data of image from the camera data bus through testing these three symbol signals and temporarily stores the data into the data memorizer in single chip microcomputer,and then transmit the data to the computer through serial communication.III.HARDWAREThe selection of apparatus in the implementation of hardware is very important for the performance of the whole system.We can select the single chip microcomputer with high cost performance and high speed,and we can also select the DSP with powerful function,quick speed,multiple interfaces and good stability as the core chip,and we can also select ARM microprocessor.As the video acquisition system,the image sensor speed used in the system can be controlled by the single chip microcomputer.When we first used51series ingle chip microcomputer in the design process,we found it couldn't fulfill the throughput of large data needed by the video acquisition.So we use ATmega16in the system which can fulfill the design requirement of the system.The single chip microcomputer of ATMEL Company is extensively applied in many domains such as industrial production control,intelligent instruments,data acquisition and home electric appliances.This kind of single chip microcomputer has the structure of RISC.Because of its advanced instruction set andsingle clock period instruction execution time,the performance of AVR single chip microcomputer can achieve16MIPS when it works in16MHz,which can reduce the conflict between power consumption and processing speed.The execution of one instruction only needs one clock cycle,and the speed is much quicker than traditional single chip microcomputer,so it can be competent for the control of A/D sampling under the condition of high speed.But when we use DSP,ARM or FPGA/CPLD,it will waste the resources and make the system become more complex,and the cost performance is not so reasonable.For the video capture equipments,whether CCD or CMOS all adopt the light-receiving component as the basic measure to capture images.The core of CCD/CMOS light receiving component is a light-receiving diode which can produce output current when receiving light irradiation.The intensity of the current is corresponding to the intensity of the irradiation.For the peripheral equipments,the light receiving component of CCD is different to the light receiving component of CMOS,and except for the light receiving diode.The light-receiving component of the former also includes one storage unit which is used to control the neighboring charge. The light-receiving diode occupies most areas,i.e.the effective light-receiving area of the CCD light-receiving component is bigger,and it can receive stronger light signal under same condition,and the corresponding output electric signals are more clear. Because the CMOS image sensor technology develops very quickly,every light-receiving component in CMOS sensor can directly integrate the amplifier and the analog-to-digital conversion logic.When the light-receiving diode receives light irradiation and produces analog electric signals,and the signals are amplified by the amplifier in the light receiving component firstly and then converted into corresponding digital signals.In another words,in the CMOS sensor,every light-receiving component can product final digital output.Because of high integration degree,small volume,convenient use and abundant image content effect captured,we adopt the camera C3088module composed by CMOS sensor(OV6620) as the acquisition equipment in the design.The default resolving capability of the camera is356*292,so it is very fit for the single chip microcomputer with low operation ability.The work voltage of the camera module C3088is5V,and its pin20and pin22 connect with the power supply,and the pin31connects with the digital earth,and the pin21,pin15and pin17connect with the analog earth.Data lines Y0~Y7connect PA0~PA7of the single chip microcomputer,and data lines UV0~UV7connect with PB0~PB7of the single chip microcomputer,and PCLK connects with PD2,and HREF connects with PD3,and VSYNC connects with PD4.SDA connects with PC1, and SCL connects with PC0.OV6620includes the image array with the resolving capability of356*292,an analog signal processor,double8bits analog-to-digital conversion,analog video multiple routes commutator,digital output format port,an analog video port,I2C bus interface and its register.The sensor uses the electric exposal control algorithm based on complete image.The single chip microcomputer selects RS232serial communication to communicate with the computer.Its circuit structure is very simple,which can ensurethe stability of the system and fulfill the design requirement of the system.RS232is one of communication interfaces on personal computer,and it is the asynchronous transmission standard interface constituted by the Electronic Industries Association (EIA).This system adopts RS232to connect with computer and transmit video data. The ATmega16adopts8bits data bit,1bit stop bit and0parity bit,and its speed can achieve230400bps,and speed of the serial port of the computer is only115200bps, which can fulfill the design requirement of the system.Because the voltage of the SCM is TTL5V and the voltage of the RS232is-12V, so both sides need level conversion to identify the other.The system needs to connect with single chip microcomputer through the chip MAX232as shown in Fig.2.The display of LCD adopts ZT018intelligent true color LCD.This module possesses basic plotting function which adopts usual microbus as the interface,so it can save development time and offer large convenience for the development and transfer.Its interface modes include SPI and I2C,and this system adopts I2C interface which only needs two data lines.IV.SFOTWAREC3088is composed by CMOS image sensor OV6620,and its initialization mainly depends on the write-operation to interior registers through I2C.Through the initialization setting of the software,the video digital output can use different formats and initialize other registers.Because the initial clock frequency of the C3088camera module is17.73MHz,when it works in the16bits data output mode,its PCLK clock cycle is112ns and when it works in the8bits data output mode,its PCLK clock cycle is56ns.The crystal oscillation adopted by the single chip microcomputer is16MHz and the single order cycle is62.5ns.So the single chip microcomputer can not follow the speed of the video.It must reduce the PCLK clock frequency through writing the register0x11,and to set the low5bits of the register in"1"can reduce PCLK to 69.25KHz,which can fit for the single chip microcomputer processing with low speed.The data output format of the usual CMOS image sensor is the original data output format.Because the CMOS optical sensor unit has different response sensitivities to three sorts of color,and the response is nonlinear.It is relative to thebrightness,plus and materials.So the original data of the image sensor should be emendated and compensated.The product compensation curves of different factories are different,so we should design different compensation algorithms.OV6620can not only output original data formats of R,G and B,and integrate color compensate algorithms in the chip,and it can output the video output formats of YUV and YCrCb according with the standard of CCIR601.The camera works in the lowest frequency through initialization.The single chip microcomputer can store the data in the data memorizer of single chip microcomputer when it read a raw of data,and it converts the data acquired by the program into the format of BMP,and transmits the data to the computer for storage and display.The serial communication is a sort of communication mode which can transmit binary system data by bit,so the quantity of the transmission lines needed by it is very few,and it is very fit for grading control system,layer-division control system, distributed control system and remote communication.Because the distributed control system is extensively applied in the modern computer control system,so it often needs one main computer to control multiple slave-computers,and the communication between the computer and single chip microcomputer becomes into an important problem.The program flow chart of single chip microcomputer is shown in Fig.3.The program flow chart of computer is shown in Fig.4.V.CONCLUSIONThe acquisition and storage of video data is the accidence of the video technology,and in the day that the video technology develops very quickly,the identification technology,digital TV and real-time supervision and control are the industries with very good foreground.The camera image acquisition system based on AVR single chip microcomputer and C3088simplifies the structure of the system.The system has clear image,and it can fulfill the requirement of real-time display and be extensively applied in network video and industrial automatic supervision. ACKNOWLEDGMENTThe work is supported by the Basic Research Program(Natural Science Foundation)of Jiangsu Province of China(Granted No.BK2007601),"Qing Lan Gong Cheng"program of Jiangsu Province of China and the Natural Science Foundation of Jiangsu Higher Education Institutions of China(Granted No. 06KJB510048).REFERENCES[1]X Ji,,Z Wei and Y Feng,Effective vehicle detection technique fortraffic surveillance systems,Journal of Visual Communication andImage Representation,2006,17(3):647-658.[2]M Valera,S A Velastin,Intelligent Distributed Surveillance Systems:a Review,IEEE Vision,Image and Signal Processing,2005,152(2): 192-204.[3]J Hsieh,Y Hsua,Boosted string representation and its application to video surveillance,Pattern Recognition2008,41(10):3078-3091. 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