OPC技术在生产调度系统中的应用

在车间级生产监控系统改造完成的基础上,针对工厂的实际情况采用OPC通讯技术,实现生产调度系统的主体功能;同时在此基础上实现无线手机短消息报警并采用VB6．0结合Excel及SQL Server2000设计调度和管理报表。     

计算机监控在低压供配电系统的运用

结合我厂供配电网络的特点，提出了在０．４ＫＶ低压供配电网络系统进行计算机实时监控和综合自动化管理。系统采用各车间分站分散采集，中心主站集中监控的方式，共同实现对全厂供配电网络系统的集中监控系统。本文从系统的结构及配置，系统功能等方面进行了概述。     

物料平衡在惠州炼化的构建与应用

通过构建物料平衡系统,惠州炼化实现了单装置和全厂物料每日高精度平衡,使全厂和各装置投入、产出和公用工程消耗以报表的形式实时展现,为生产管理人员和统计人员提供了准确的信息。惠州炼化在物料平衡的基础上融入了价格管理体系,创建出经济核算模型,对各装置和全厂进行成本利润日测算,强化了生产组织和操作调整的针对性,能够对市场变化及时做出反应。     

基于组件的自定义报表系统的设计与实现

传统报表定制方式中报表数据项和报表界面是固定的,使系统后期维护繁重并且难以实现用户的需求.针对上述问题,提出了基于组件的自定义报表系统的设计方法,给出了基于组件技术的自定义报表系统的功能模型、组件层次模型以及实现框架,通过设计各类型组件实现了用户可自定义报表数据项和报表界面的功能.将组件技术应用到系统开发中,提高了系统开发效率,降低了开发成本,使系统更易维护、扩展和升级.     

基于Ajax 技术的WinCC 网络报表系统

WinCC组态软件功能强大,但是它的报表功能并不完善,网络报表的功能需要通过昂贵的组件WebNavigator来实现,有时无法满足项目需求．针对WinCC报表功能的不足,在研究分析了WinCC数据归档结构后,基于Ajax、ASP等网络技术提出了实现WinCC网络报表系统．系统直接读取SQLServer归档数据库,实现远程浏览WinCC报表、趋势图表的功能,同时具有类似桌面程序的用户体验．将该系统应用于某污水处理过程中取得了良好的效果．     

国产DCS、DEH、MEH、BOP控制系统全厂一体化在2×350MW超临界燃煤机组中的应用

山东某发电2×350MW超临界燃煤机组自动化控制系统选用了国产和利时公司的HOLLiAS-MACS控制系统,并且实现分散控制系统(DCS)、汽轮机数字电液控制系统(DEH)、给水泵小汽轮机数字电液控制系统(MEH)、辅助车间控制系统(BOP)控制系统全厂一体化功能,完成整套机组及辅网的集中监控。文中对该系统的结构、软硬件设计的特点作了详细介绍和分析。对HOLLiAS-MACS控制系统在350MW及以上机组采用全厂一体化控制发展前景做了展望。     

多协议网关在PLC通信系统中的应用

采用多协议网关,使车间中的ControlLogix系统成功读写Siemens S7-200中的控制变量,在不影响ControlLogix冗余系统运行的情况下,实现中控室对全厂自动化设备的监控。     

基于施耐德67160CPU实现报表功能的方法探讨

在监控系统中,报表功能作为重要的管理功能之一,其实现方法大多局限于上位机中实现。本文基于下位机实现了配料系统中的计量功能,较好的实现了报表功能。为基于PLC和组态软件为平台实现实时性和可靠性较高的监控系统进行了有意的实践和探索。     

企业销售系统中水晶报表的web实现

该文中介绍了水晶报表及功能,并且简要地分析了水晶报表访问数据库的两种模式,以及水晶报表所需要的Web应用组件。重点介绍了企业销售系统报表的Web实现过程。通过对水晶报表的Web实现原理和方法介绍,以及服务器的安装配置过程的描述,一直到水晶报表在企业系统Web页面上最终实现的效果,完整地介绍了企业销售系统水晶报表的Web实现过程。     

WinCC报表在提钒半钢冶炼中的实践应用

本文以半钢冶炼自动化系统中的电子报表系统为例,探讨了工控系统报表功能的设计思路,利用WinCC的开放性技术及报表编辑器,实现了报表的所有核心功能,并结合项目实施过程中的实际经验及软件特点,对WinCC报表开发提出了优化方法和改进思路。     

Shop floor control in computer-integrated manufacturing for large-scale integrated wafer fabrication systems

Manufacturing technology in the field of Large-Scale-Integrated (LSI) circuit production has overcome the problems of enlarged wafer size and increasing level of integration. The market environment of the LSI industry has become more demanding with increased requirements, delivery time and stiffer cost competition. A Computer-Integrated Manufacturing System (CIMS) well-adapted to the unique characteristics of LSI production system is thus urgently needed.

This paper describes the development of CIMS in LSI production systems, and presents the example of a DTS (Diffusion Total System), constructed in a real LSI wafer fabrication factory. Features of DTS are (a) on-line real-time manufacturing data acquisition and monitoring through a production information network, (b) automatic control of process equipment, (c) shop floor control for computer aided decision support at the shop floor level, and (d) data analysis and reporting derived from a large amount of accumulated data. This paper deals with shop floor control, and in particular with a priority control system unique to the LSI wafer fabrication line.     

基于Web的水泥企业网络视频监控系统研究

基于C／S网络模式及Internet网络技术,描述水泥企业远程视频监控系统的基本硬件结构及视频信息和控制信息在系统中的传输过程,提出水泥企业网络远程监控系统中几个关键技术的实现方法,针对系统中的管理架构、总厂调度监控中心、各分厂视频监控系统及分厂视频传输与处理进行较为详细的阐述。     

A survey of multi-factory scheduling

Because of current globalization trend, production has shifted from the single factory production to multi-factory production network. To become competitive in today’s rapidly changing market requirements, factories have shifted from a centralized to a more decentralized structure, in many areas of decision making including scheduling. In multi-factory production network, each factory can be considered as an individual entity which has different efficiency and is subject to different constraints, for example, machine advances, worker cost, tax, close to suppliers, and transportation facilities, etc. Since limited resources make scheduling an important decision in the production, for several decades, researchers focused on determining an efficient schedule to improve the productivity. The recent remarkable attention in distributed production management in both academia and the industry has demonstrated the significance of multi-factory scheduling. For the first time, this paper provides a review on the multi-factory machine scheduling. For this, first, the paper classifies and reviews the literature according to shop environments, including single machine, parallel machines, flowshop, job shop, and open shop. Then the reviewed literature is quantified and measured. At the end, the paper concludes by presenting some problems receiving less attention than the others and proposes several research opportunities in the field.     

RFID-enabled automation in support of factory integration

In recognition of the need for more effective and efficient factory system integration solutions, this paper improves the method proposed in our previous work, focusing on new mechanisms to bridge the gap between shop floor automation and factory information systems. As one of the mainstream identification technologies, radio frequency identification (RFID) technology makes possible all products uniquely identifiable across factories. By taking advantage of data capacity stored in an RFID tag, critical manufacturing information on a product can be locally stored with the product. RFID technology provides a means for a product to rapidly retrieve its needed information as it advances through shop floors. A corresponding framework to enable the instant delivery of pertinent data and information on a uniquely identifiable job/product at point-of-need across factories is proposed. A small-scale manufacturing application is presented to show how the proposed approach can be implemented on the shop floor.     

制药工厂OEE系统的应用

针对制药工厂自动化应用的发展,以及工厂管理层对车间管理的进一步要求,提出了车间管理的一些典型问题并采用了 OEE(Overall Equipment Effectiveness,全面设备效率)系统.利用当今的一些自动化应用技术、软件编程技术以及系统集成技术,部分给出了较合理的问题解决手段,为后续全面实施MES (Manufacturing Execution System,制造执行系统)积累了经验.同时还满足了有关CSV (Computer System Validation,计算机系统验证)的规范.     

Throughput analysis in automotive paint shops: a case study

In this paper, an overlapping decomposition method is used to estimate the throughput of a production system with multiple rework loops. The idea of the method is to decompose the system into a couple of serial lines and modify the parameters of overlapping machines to accommodate the effects of other lines. Using this method, the throughput of an automotive paint shop is analyzed and continuous improvement procedures are described.

Note to Practitioners-Painting is an important element of vehicle production. A paint shop has been a system bottleneck in many automotive assembly plants due to its complexity. Fast and accurate analysis of its system throughput is important for design and continuous improvements. This paper introduces an iterative method to analyze the performance of paint shop type production systems, i.e., systems with multiple rework loops. The method has obtained good results in both theoretical study and applications on the factory floor. In addition, a case study at an automotive paint shop is introduced and continuous improvements process to identify and eliminate system bottlenecks is described. The presented method can also be applied to other production systems with similar structures.     

A machine learning approach to predict production time using real-time RFID data in industrialized building construction

Industrialized building construction is an approach that integrates manufacturing techniques into construction projects to achieve improved quality, shortened project duration, and enhanced schedule predictability. Time savings result from concurrently carrying out factory operations and site preparation activities. In an industrialized building construction factory, the accurate prediction of production cycle time is crucial to reap the advantage of improved schedule predictability leading to enhanced production planning and control. With the large amount of data being generated as part of the daily operations within such a factory, the present study proposes a machine learning approach to accurately estimate production time using (1) the physical characteristics of building components, (2) the real-time tracking data gathered using a radio frequency identification system, and (3) a set of engineered features constructed to capture the real-time loading conditions of the job shop. The results show a mean absolute percentage error and correlation coefficient of 11% and 0.80, respectively, between the actual and predicted values when using random forest models. The results confirm the significant effects of including shop utilization features in model training and suggest that predicting production time can be reasonably achieved.     

基于PROFINET的烟厂电力监控系统设计

为提高烟厂电力监控系统的自动化程度和可靠性,提出了基于PROFINET烟厂电力监控系统：把仪表、组态软件与PROFINET结合。该系统将硬件电路组装在开关柜中,通过组态软件开发设计监控软件,显示系统的配置及各种电气参数,实时控制现场各用电设备,实现配电网数据采集、监控和管理。整个系统集成度高,能满足烟厂电力监控系统分散化、网络化、智能化的要求。     

A computer simulation model for job shop scheduling problems minimizing makespan

One of the basic and significant problems, that a shop or a factory manager is encountered, is a suitable scheduling and sequencing of jobs on machines. One type of scheduling problem is job shop scheduling. There are different machines in a shop of which a job may require some or all these machines in some specific sequence. For solving this problem, the objective may be to minimize the makespan. After optimizing the makespan, the jobs sequencing must be carried out for each machine. The above problem can be solved by a number of different methods such as branch and bound, cutting plane, heuristic methods, etc. In recent years, researches have used genetic algorithms, simulated annealing, and machine learning methods for solving such problems. In this paper, a simulation model is presented to work out job shop scheduling problems with the objective of minimizing makespan. The model has been coded by Visual SLAM which is a special simulation language. The structure of this language is based on the network modeling. After modeling the scheduling problem, the model is verified and validated. Then the computational results are presented and compared with other results reported in the literature. Finally, the model output is analyzed.     

A heuristic algorithm for the distributed and flexible job-shop scheduling problem

The distributed manufacturing takes place in a multi-factory environment including several factories, which may be geographically distributed in different locations, or in a multi-cell environment including several independent manufacturing cells located in the same plant. Each factory/cell is capable of manufacturing a variety of product types. An important issue in dealing with the production in this decentralized manner is the scheduling of manufacturing operations of products (jobs) in the distributed manufacturing system. In this paper, we study the distributed and flexible job-shop scheduling problem (DFJSP) which involves the scheduling of jobs (products) in a distributed manufacturing environment, under the assumption that the shop floor of each factory/cell is configured as a flexible job shop. A fast heuristic algorithm based on a constructive procedure is developed to obtain good quality schedules very quickly. The algorithm is tested on benchmark instances from the literature in order to evaluate its performance. Computational results show that, despite its simplicity, the proposed heuristic is computationally efficient and promising for practical problems.