ON-LINE PROBLEMS OF MINIMIZING MAKESPAN ON A SINGLE BATCH PROCESSING MACHINE WITH NONIDENTICAL JOB SIZES

The on-line problem of scheduling on a batch processing machine with nonidentical job sizes to minimize makespan is considered. The batch processing machine can process a number of jobs simultaneously as long as the total size of these jobs being processed does not exceed the machine capacity. The processing time of a batch is given by the longest processing time of any job in the batch. Each job becomes available at its arrival time, which is unknown in advance, and its processing time becomes known upon its arrival. The paper deals with two variants： the case only with two distinct arrival times and the general case. For the first case, an on-line algorithm with competitive ratio 119/44 is given. For the latter one, a simple algorithm with competitive ratio 3 is given. For both variants the better ratios can be obtained if the problem satisfies proportional assumption.

Modeling of Microstructure Evolution and Mechanical Properties of Steel Plates Produced by Thermo-Mechanical Control Process and Its On-line Application

An integrated metallurgical model was developed to predict microstructure evolution and mechanical properties of low-carbon steel plates produced by TMCP. The metallurgical phenomena occurring during TMCP and mechanical properties were predicted for different process parameters. In the later passes full recrystallization becomes difficult to occur and higher residual strain remains in austenite after rolling. For the reasonable temperature and cooling schedule, yield strength of 30 mm plain carbon steel plate can reach 310 MPa. The first on-line application of prediction and control of microstructure and properties (PCMP) in the medium plate production was achieved. The predictions of the system are in good agreement with measurements.

On-line Batch Process Monitoring and Diagnosing Based on Fisher Discriminant Analysis

A new on-line batch process monitoring and diagnosing approach based on Fisher discriminant analysis （FDA） was proposed. This method does not need to predict the future observations of variables, so it is more sensitive to fault detection and stronger implement for monitoring. In order to improve the monitoring performance, the variables trajectories of batch process are separated into several blocks. The key to the proposed approach for on-line monitoring is to calculate the distance of block data that project to low-dimension Fisher space between new batch and reference batch. Comparing the distance with the predefine threshold, it can be considered whether the batch process is normal or abnormal. Fault diagnosis is performed based on the weights in fault direction calculated by FDA. The proposed method was applied to the simulation model of fed-batch penicillin fermentation and the resuits were compared with those obtained using MPCA. The simulation results clearly show that the on-line monitoring method based on FDA is more efficient than the MPCA.

Towards On-line Automated Semantic Scoring of English-Chinese Translation

Described and exemplified a semantic scoring system of students' on-line English-Chinese translation. To achieve accurate assessment, the system adopted a comprehensive method which combines semantic scoring with keyword matching scoring. Four kinds of words-verbs, adjectives, adverbs and "the rest" including nouns, pronouns, idioms, prepositions, etc., are identified after parsing. The system treats different words tagged with different part of speech differently. Then it calculated the semantic similarity between these words of the standard versions and those of students' translations by the distinctive differences of the semantic features of these words with the aid of HowNet. The first semantic feature of verbs and the last semantic features of adjectives and adverbs are calculated. "The rest" is scored by keyword matching. The experiment results show that the semantic scoring system is applicable in fulfilling the task of scoring students' on-line English-Chinese translations.

On-line monitoring of insulation quality of high voltage electric power equipment

Discusses on-line monitoring of electric parameters, such as dielectric loss, divulging current, equivalent capacitance and running voltage, and presents an on-line monitoring system of insulation quality, based on monitoring divulging current and dielectric loss of high voltage equipment, and its advantages, such as helping people to discover the hidden problems in a timely manner, to reduce power cut and overhaul and to improve security of power supply.

An On-line Assessment System for English-Chinese Translation

On-line assessment of English-Chinese translation is a challenging task as it involves natural language processing.YanFa,an on-line assessment system for English-Chinese translation,is a pilot research project into scoring student's translation on-line.Based on the theory of translation equivalence,an algorithm called "conceptual similarity matching" was developed.YanFa can assess students' translation on-line timely,generate test papers automatically,offer standard versions of translation,and the scores of each sentence to students.The evaluation proves that YanFa is practical compared with the scores given by experts.

On-line Scheduling Algorithm for Penicillin Fed-batch Fermentation

An on-line scheduling algorithm to maximize gross profit of penicillin fed-batch fermentation is proposed. According to the on-line classification method, fed-batch fermentation batches are classified into three categories. Using the scheduling strategy, the optimal termination sequence of batches is obtained. Pseudo on-line simulations for testing the proposed algorithm with the data from industrial scale penicillin fermentation are carried out.

Situation and Developing Trend of Rare-Earth Countercurrent Extraction Processes Control

On the basis of the description of the rare-earth countercurrent extraction process, the on-line detecting method and equipments of rare-earth elements and the application in the process of the rare-earth countercurrent extraction are summarized. The procedure simulation of the computer, the automation control method and its current application are also mentioned in the process of rare-earth countercurrent extraction. The method of soft sensor is proposed. Optimal control method based on object-oriented rare-earth countercurrent extraction process and integrated automation system composed of process management system and process control system are presented, which are the developing direction of the automation of rare-earth countercurrent extraction process.

A Review: Artificial Neural Networks as Tool for Control Food Industry Process

In the last year, interest in using Artificial Neural networks as a modeling tool in food technology is increasing because they have found extensive utilization in solving many complex real world problems. Due to this and as previous step at development of some project, this paper intends to introduce the reader inside neural networks: general characteristics of the ANN, their architectures, their rules of learning, types of networks and ANN’s create process. Also this paper presents a comprehensive review of food industrial applications of artificial neural networks in the last year. ANN industrial applications are grouped and tabulated by their main functions and what they actually performed on the referenced papers with except the applications in the olive oil industry that are described with special emphasis.

VPLS Based Quality and Cost Control for Tennessee Eastman Process

Product quality and operation cost control obtain increasing emphases in modern chemical system engineering. To improve the fault detection power of the partial least square (PLS) method for quality control, a new QRPV statistic is proposed in terms of the VP (variable importance in projection) indices of monitored process variables, which is significantly advanced over and different from the conventional Q statistic. QRPV is calculated only by the residuals of the remarkable process variables (RPVs). Therefore, it is the dominant relation between quality and RPV not all process variables (as in the case of the conventional PLS) that is monitored by this new VP-PLS (VPLS) method. The combination of QRPV and T2 statistics is applied to the quality and cost control of the Tennessee Eastman (TE) process, and weak faults can be detected as quickly as possible. Consequently, the product quality of TE process is guaranteed and operation costs are reduced.

Recent Progress of Commercially Available Biosensors in China and Their Applications in Fermentation Processes

Biosensors, which are the products of the biotechnology industry, are among the key projects of the 7th, 8th, and 9th Fiveyear Plans of China Science ＆ Technology Developing Programs, respectively, and they play an important role in developing and reforming traditional biotechnology. SBA series biosensor analyzer, as the only one commercial biosensor in China, has attracted lots of attention in the process of information gathering and measurement for biological industry with the development of technology and society. In this paper, we presented an overview of the most important contributions dealing with the monitoring of the biochemical analytes in fermentation processes using SBA series biosensor analyzers in China. Future trends of the biosensor analyzer in China were also mentioned in the last section.

An FPGA-based real-time image processing system

This paper analyzes the current difficulties encountered in on-line inspection systems of strip surface quality, specifically relating to problems with real-time processing of huge amounts of data. To address this need, this paper describes an FPGA-based high-speed image processing module with both hardware and software aspects. Improving these two aspects together will help the system achieve real-time processing of massive image data, and simplifies the architecture of the strip surface quality on-line inspection system.

国产T800级航空预浸料固化动力学研究及TTT图绘制

成型工艺的确定是复合材料制件批量化生产的先决条件,材料与工艺是否适配将直接影响复材制件的外观(如表面胶瘤、贫胶等)、外形(如轮廓度、变形等)、孔隙率等,而预浸料的固化动力学研究及TTT图是复合材料预成型、固化成型工艺制订与优化的重要研究方法与参考依据。以国产T800级航空预浸料为主要研究对象,通过差示扫描量热法建立混合固化动力学模型,拟合结果与实验结果相符,拟合系数达0.99;以流变测试结果构建化学流变方程与凝胶方程,结合动力学模型计算该预浸料的平均凝胶固化度为0.375;基于玻璃化温度(Tg)与固化度测试结果形成Di Benedetto拟合方程,结合动力学方程、凝胶方程、流变方程结果,绘制了预浸料的TTT图,并以实际固化工艺过程温度监测结果验证此动力学方程与TTT图的有效性。

玻璃纤维/环氧树脂预浸料固化全过程的比热容和热导率研究

通过调制温度式差示扫描量热技术(MDSC)测定了玻璃纤维/环氧树脂预浸料在固化全过程不同方向上的比热容和热导率,并建立模型来描述比热容和热导率随温度和固化度的变化。未固化和完全固化时,预浸料的比热容和热导率随着温度的增大线性增加;在固化过程中受温度和固化度的双重影响,在固化反应前期,比热容和热导率有一个突变,在温度和固化度的作用下表现出先增大后减小的趋势。此外,通过混合定律和分段线性关系来描述比热容和热导率随温度和固化度的变化关系,结果有助于提高数值模拟中参数的准确性。

基于OLAP的上海社区服务网后台数据仓库的设计与实现

首先给出数据仓库以及OLAP等一些相关概念,然后叙述了OLAP多维数据分析的几种方法,最后介绍了基于OLAP的上海社区服务网后台数据仓库的设计方案及其具体实现方法。

碳纤维/环氧复合材料孔隙缺陷的工艺影响因素研究

针对复合材料热压工艺建立了一套可以研究孔隙形成规律的工艺实验模拟装置,采用该装置考查了成型压力、加压点、吸胶方式、试样厚度等因素对孔隙的影响。结果表明,所建立的研究方法可以获取孔隙与工艺因素的关联规律;对于MT300/603碳纤维/环氧预浸料,成型压力的增大与加压点温度的降低都可以降低孔隙率与孔隙尺寸,但压力对于孔隙率的消除效果更明显;孔隙消除机理中的树脂流动带出气泡起主要作用,而压力的压溃和排气作用起次要作用;铺层厚度对孔隙形成有明显影响。研究结果对于热压工艺复合材料孔隙缺陷的控制提供了重要的研究手段和实验依据。

碳纤维/环氧预浸料的热固化工艺研究

以先进拉挤(Advanced Pultrution)[1]ADP成型技术为研究背景,借助差示扫描量热法(DSC)对USN12500碳纤维/环氧预浸料固化所涉及的温度和时间进行了研究与分析。以弯曲强度作为考察指标设计正交试验,优选了模拟的拉挤成型固化工艺参数。试验结果表明,①后固化温度下的保温时间对制品的力学性能影响最大,预处理温度下的保温时间影响最小;②预处理温度80℃下处理25min、热压温度130℃下保温保压25min以及后固化温度150℃下保温1.5h为本组试验的优方案。

热隔膜工艺温度与成型速率对C形复合材料成型质量的影响

利用自制的热隔膜成型设备制备C形结构碳纤维/环氧预浸料预成型体,通过对预成型体的厚度、缺陷进行表征,考察了工艺温度、成型速率对C形预成型体成型质量和预浸料层间摩擦阻力的影响,分析了预浸料摩擦滑移特性与热隔膜工艺成型质量的关联性。结果表明:通过提高工艺温度、降低抽真空速率可以降低预浸料层间摩擦阻力,得到成型质量较好的C形预成型体。热隔膜成型工艺条件对预浸料层间摩擦滑移特性有重要影响,摩擦阻力可以作为优化热隔膜成型工艺参数的重要依据。

SW280玻璃布/苯并噁嗪热熔法预浸料的性能研究

本文采用热熔法制备SW280玻璃布/苯并噁嗪预浸料,并对苯并噁嗪树脂工艺性、热失重性能,及复合材料动态热机械性能、高温力学性能保持率、阻燃性能等进行工艺试验和性能评价。结果表明,苯并噁嗪树脂软化点在41~42℃,最低黏度点为1835m Pa·s,满足热熔法预浸料的制备要求;氮气氛围下起始分解温度280℃左右,800℃时残碳率可达61.3%。SW280玻璃布/苯并噁嗪复合材料力学性能优异,界面粘接良好,玻璃化转变温度为200℃,其200℃高温下的压缩强度、弯曲强度、弯曲模量和层剪强度保持率分别为90.6%、59.4%、83.2%和62.7%。SW280玻璃布/苯并噁嗪复合材料阻燃性能优异,无焰和有焰模式下最大烟密度均为0,氧指数〉58%,燃烧等级为V-1。

自动铺丝过程中预浸料的侧向弯曲

根据自动铺丝过程中预浸料的受力特点,建立预浸料的侧向弯曲变形模型。利用最小势能原理、瑞利-利兹法以及相关的复合材料力学理论,推导出预浸料侧向屈曲半径公式。研究自动铺丝温度、压力、速度、黏附力等主要工艺参数对侧向弯曲性能的影响,并用自动铺丝机铺放不同半径的预浸料圆弧进行验证。结果表明:随着温度增大、压力和速度减小,预浸料的侧向弯曲性能提高;增加预浸料黏附力可显著提高其侧向弯曲性能,符合理论分析结果。