The data flow modelling technique is used during the analysis phase to provide a common vehicle , in the form of diagrams and associated descriptions , to communicate with users and among developers 数据流程模型数据流程模型是在系统分析阶段时所使用的技巧。这个模型以图表及辅以文字的方式，来作为系统发展人员之间及与用户沟通的共通方法。
It introduces the architecture , usb data flow model and usb device framework . and it also gives a specific description for usb mass storage class specification and usb mass storage bulk - only transport specification used by the project 介绍了usb的体系结构,数据流模型以及设备框架,并对实际应用中所遵从的usbmassstorage类规范和usbmassstoragebulk - only传输规范做了专门的阐述。
It investigates the information flow associated with the services currently provided , and describes them in the form of data flow model . at this point , the data flow model represents the current services with all their deficiencies 这个步骤是要调查现时所提供服务的相关资讯流程，并以数据流程模型描绘出来。在这步骤所制成的数据流程模型只需勾划出现有服务及其不足处，而毋须把需要改善的地方或新设施辑纳在内。
The forth and fifth chapter are the kernal part of this paper , in the first we present the data flowing model between data tier and logistic , get a meta model of it , and realization it , in the later we present you the data flowing model between view and logistic , get a meta model and realization it in java 第四部分和第五部分是本文的核心，其中第四部分是总结出数据层和逻辑层数据交互的模型，抽象出其元模型，并在java环境下实现该元模型。第五部分是总结表示层和逻辑层数据层交互的模型，并在模型的基础上提出元模型及在java下的实现。
Chapter three , according to the necessity of the production management systems of the tobacco enterprises , puts forward the body functioning frames of the production planning and scheduling , designs main functions ; then brings forward the data flow models and realizes partial database designing 第三章针对烟草行业生产管理系统的需求，提出了面向烟草行业的生产计划和生产调度的总体功能框架，并设计了主要模块的功能；然后提出生产管理的数据流模型，并实现部分数据库设计。
Three tiers structure of sofeware which have been used in the sofeware system broadly , the first research objects , conclude the data flowing model between data tier and logistic and the data flowing model between view and logistic , then build the meta model of the two model , at last realizing the two meta model basing on using xml and software reusability , 作者通过对现在广泛应用的三层体系结构和n层体系结构的分析入手，提出数据层和逻辑之间交互的模型，逻辑层和表示层之间交互的模型，并在此模型的的基础上提出他们的元模型，利用xml技术，软件复用思想，在java环境下实现这两个元模型。
