基于莫迪康称重模块的自动配料系统

本文详细介绍了安钢360平米烧结机自动配料配料系统的主要组成、智能电子皮带秤及测速传感器的工作原理和安装等,同时也以应用的角度详细论述了称重模块、PLC、变频器三者之间的通讯.此外介绍了本系统的软件及实现的功能.     

新一代配料控制器及其应用

9215单秤自动配料控制器集配料控制和PLC功能为一体,具有墙挂式和面板式两种基本结构,应用于模拟传感器及数字传感器秤。 9215可控制16料双速自动配料。零点和目标误差检查、提前量、自动提前量调整和自动补料等配料控制技术均在9215中实现。下面主要介绍面板式9215配料控制器特点及其应用。一、面板式9215配料控制器工业配料系统的核心是配料控制器,由它控制原始成分的称重和配料。托利多9215面板式配料控制器由8142/8510称重显示仪、9215控制器、手动控制器、Smart Link I/O板组成,如图1所示。     

基于DAQFactory组态软件的自动配料系统

简要介绍了自动配料系统的工作与控制原理,并详细介绍了基于最新一代组态软件的自动配料系统的设计.实践结果表明,此设计方案合理,可靠性、精确性与工作效率都明显高于手动配料.     

烧结矿配料的计算系统

本文描述了冶金系统的烧结矿配料的计算系统软件的数据流图、计算方法及存储结构,以及该软件的核心模块--配料计算模块的程序流程图.通过使用此软件,使烧结矿配料的计算更加准确、快捷,并可有效地从宏观上控制烧结矿成本.     

迭代学习控制在配料控制系统中的应用

针对某水泥厂原有的配料控制器存在的配比不准、精度不高和稳定性差等方面的不足,着重论述了称量配料过程中的精度控制,通过分析动态称量配料过程的物理机理,建立了动态称量配料过程的数学模型并进行了定性分析,并利用迭代学习的控制算法对水泥配料控制器进行了改进,对控制算法进行了详细的介绍,结果表明,该控制方法较传统控制方法在控制精度上有了明显提高。     

玻璃窑炉配料系统自动控制的设计与实现

分析了窑炉配料自动控制的重要性，详细介绍了采用PLC和配料控制器组成的玻璃窑炉配料控制系统的组成及控制方法。生产实践证明，该系统控制配料精度高，性能可靠，具有广泛应用价值。     

JAGUAR工业称重终端在石灰窑配料系统中的应用

0 引言石灰窑是氨碱法制碱重要设备之一,它将石灰石进行煅烧,供给制碱所需的优质石灰与合格的窑气.某碱业公司现有6座石灰窑,从1996年5月使用Met-tler-ToedO Jaguara 业称重终端做为配料生产的关键配料设备,从而使石灰窑配料系统更趋完善.1 石灰窑配料工况及要求1.1 石灰窑配料工况石灰窑配料斗下部装有Mettler-Toledo称重模块3个,各个模块的量程范围为2t,3个模块分别为浮动式、半浮动式、固定式,料斗为方形,安装位置见图1.     

基于解析结构的模糊PI圆盘配料控制器

针对圆盘配料过程时变、非线性的特性,设计一种基于解析结构的模糊PI控制器。将料流量偏差和偏差变化率作为输入,采用等差间距的隶属度函数和sum-product推理方法,根据模糊控制规则得到PI参数调整的解析表达式。利用该解析表达式,对圆盘配料控制系统进行仿真,仿真结果验证了该控制器的有效性和实用性。     

模型驱动算法在皮带配料系统中的应用研究

在选煤厂皮带配料系统中,皮带秤的连续配料和称重存在着控制精度不足,抗干扰力弱等缺陷,常规的PID控制器和模糊PID控制器已不能满足大型煤矿复杂多变的工作环境和生产要求,现改用二自由度模型驱动PID控制器对其进行优化设计,并对被控对象的相关参数进行计算与修正,同时运用Matlab仿真试验进行研究,结果表明优化后的皮带配料控制系统具有超调量小、调节时间短、响应速度快、抗干扰能力强等优点,能够有效地改善皮带配料控制系统的动态品质,提高了系统的配料精度和配料速度.     

电子负秤原理及其在混凝土自动配料设备中的应用

阐述了电子负秤的基本原理,对比分析了正秤和负秤在混凝土配料计量方面的性能。介绍了一种新颖的计算机控制的混凝土自动配料机。该配料机首次采用电子负秤这一独特的计量原理,结构设计简单、合理,具有较高的性能价格比。最后探讨了消除或减少系统配料误差的几种方法。     

烧结生产自动配料控制系统

介绍了烧结生产自动配料控制系统的组成及工作原理.控制系统采用上下两级的计算机控制形式,并在系统的设计中,根据生产的实际情况采用了新的控制思想和控制方法.     

数据流系统中一种基于速率的抢占式批处理方法

针对数据流的特征,提出了一种基于速率的抢占式批处理方法。一个查询计划是一个操作符序列。文章将一个查询计划划分为不同的操作单元,并为不同的操作单元分配不同的优先级,而且这个优先级随系统因素的变化而动态改变,根据变化的优先级来动态调度操作单元,采取抢占式调度,从而提高连续查询的查询效率。实验表明该方法不但能提高系统的总体性能,而且可以减少元组的平均等待时间,大大提高了元组的输出速率。     

视频点播系统中Batching调度方案的一种改进实现

节目调度是视频点播系统设计与实现的一个重要问题。本文首先对视频点播系统中的节目调度方案作了探讨，然后提出一种Batching调度方案的改进实现方法。理论与实验证明，该方法可以有效地提高视频点播系统的服务水平。     

The unbounded single machine parallel batch scheduling problem with family jobs and release dates to minimize makespan

In this paper we consider the unbounded single machine parallel batch scheduling problem with family jobs and release dates to minimize makespan. We show that this problem is strongly NP-hard, and give an O(n(n/m+1)^m) time dynamic programming algorithm and an O(mk^k+1P^2k−1) time dynamic programming algorithm, where n is the number of jobs, m is the number of families, k is the number of distinct release dates and P is the sum of the processing times of all families. We further give a heuristic with a performance ratio 2. We also give a polynomial-time approximation scheme for the problem.     

基于电子正秤的配料控制系统计量误差分析

本文主要是对当今基于电子正秤的自动配料控制系统称量误差产生的原因作了详尽的分析，并提出行之有效的解决办法来降低误差，提高自动配料控制系统的配料精度。     

Two-stage hybrid batching flowshop scheduling with blocking and machine availability constraints using genetic algorithm

This research investigates a two-stage hybrid flowshop scheduling problem in a metal-working company. The first stage consists of multiple parallel machines and the second stage has only one machine. Four characteristics of the company have substantiated the complexity of the problem. First, all machines in stage one are able to process multiple jobs simultaneously but the jobs must be sequentially set up one after another. Second, the setup time of each job is separated from its processing time and depends upon its preceding job. Third, a blocking environment exists between two stages with no intermediate buffer storage. Finally, machines are not continuously available due to the preventive maintenance and machine breakdown. Two types of machine unavailability, namely, deterministic case and stochastic case, are identified in this problem. The former occurs on stage-two machine with the start time and the end time known in advance. The latter occurs on one of the parallel machine in stage one and a real-time rescheduling will be triggered. Minimizing the makespan is considered as the objective to develop the optimal scheduling algorithm. A genetic algorithm is used to obtain a near-optimal solution. The computational results with actual data are favorable and superior over the results from existing manual schedules.     

Optimizing a production system with rework and equal sized batch shipments

In several cases producing new or recovering defective products takes place on a common facility, with these activities are carried out in lots. Consequently, there is a necessity to coordinate the production and rework activities with respect to the timing of operations and also with regard to appropriate lot sizes for both processes while completely satisfying a given demand. Thereby, a decision has to be made on how to assign units completed at one stage to partial lots—called batches—for shipment to the next operation. In this paper we present a lot size model which addresses all of these aspects. Based on total relevant costs per unit time, an optimization method is developed to determine the economic production and rework quantity as well as the corresponding batch sizes for both activities. The algorithm is illustrated by a numerical example followed by a sensitivity analysis of the models behavior under different problem parameters.     

Batch scheduling of step deteriorating jobs

In this paper we consider the problem of scheduling n jobs on a single machine, where the jobs are processed in batches and the processing time of each job is a step function depending on its waiting time, which is the time between the start of the processing of the batch to which the job belongs and the start of the processing of the job. For job i, if its waiting time is less than a given threshold value D, then it requires a basic processing time a _i ; otherwise, it requires an extended processing time a _i +b _i . The objective is to minimize the completion time of the last job. We first show that the problem is NP-hard in the strong sense even if all b _i are equal, it is NP-hard even if b _i =a _i for all i, and it is non-approximable in polynomial time with a constant performance guarantee Δ<3/2, unless . We then present O(nlog n) and O(n ^3F−1log n/F ^F ) algorithms for the case where all a _i are equal and for the case where there are F, F≥2, distinct values of a _i , respectively. We further propose an O(n ²log n) approximation algorithm with a performance guarantee for the general problem, where m ^* is the number of batches in an optimal schedule. All the above results apply or can be easily modified for the corresponding open-end bin packing problem.     

应用批处理实现学校机房高效管理

批处理命令简洁而高效,在许多不便安装硬件还原卡的学校机房,系统维护工作比较繁琐,应用批处理命令实现了开机自动系统优化,以及网络克隆后自动修改机器配置,为学校机房管理提供了一条比较实用方便的维护管理方法。     

Multicast video-on-demand service in an enterprise network with client-assisted patching

Multicast Video-on-Demand (VoD) systems are scalable and  cheap-to-operate. In such systems, a single stream is shared by a batch of common user requests. In this research, we propose multicast communication technique in an Enterprise Network where multimedia data are stored in distributed servers. We consider a novel patching scheme called Client-Assisted Patching where clients’ buffer of a multicast group can be used to patch the missing portion of the clients who will request the same movie shortly. This scheme significantly reduces the server load without requiring larger client cache space than conventional patching schemes. Clients can join an existing multicast session without waiting for the next available server stream which reduces service latency. Moreover, the system is more scalable and cost effective than similar existing systems. Our simulation experiment confirms all these claims.