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Study on the Interactivity of Controlled and Automatic Information Processing in L2 Reading
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作者 DONG Tiantian WANG Yong 《Sino-US English Teaching》 2024年第7期314-321,共8页
L2 reading is not only an important channel for people to obtain information and knowledge,but also the main way for people to learn a foreign language.Reading information processing can be divided into controlled pro... L2 reading is not only an important channel for people to obtain information and knowledge,but also the main way for people to learn a foreign language.Reading information processing can be divided into controlled processing and automatic processing.Controlled information processing is a conscious and resource-intensive processing model,while automatic information processing is an unconscious and automatic processing model.This study investigates the characteristics and interactivity of controlled and automatic information processing in L2 reading,and explores the roles of controlled and automatic information processing strategies in improving L2 reading ability.The findings are as follows:(a)controlled and automatic information processing is interactive in L2 reading;and(b)the uses of controlled and automatic information processing strategies are beneficial to the improvement of the reading ability of L2 learners.This study has important theoretical and practical value in improving the efficiency of L2 reading teaching and learning. 展开更多
关键词 L2 reading controlled information processing automatic information processing interactivity
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Optimal tracking control for automatic transmission shift process 被引量:2
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作者 万国强 李克强 +2 位作者 裴玲 黄英 张付军 《Journal of Beijing Institute of Technology》 EI CAS 2015年第4期458-465,共8页
In order to improve the shift quality, a linear quadratic optimal tracking control algorithm for automatic transmission shift process is proposed. The dynamic equations of the shift process are derived using a Lagrang... In order to improve the shift quality, a linear quadratic optimal tracking control algorithm for automatic transmission shift process is proposed. The dynamic equations of the shift process are derived using a Lagrange method. And a powertrain model is built in the Matlab/Simulink and veri- fied by the measurements. Considering the shift jerk and friction loss during the shift process, the tracking trajectories of the turbine speed and output shaft speed are defined. Furthermore, the linear quadratic optimal tracking control performance index is proposed. Based on the Pontryagin' s mini- mum principle, the optimal control law of the shift process is presented. Finally, the simulation study of the 1 - 2 upshift process under different load conditions is carried out with the powertrain model. The simulation results demonstrate that the shift jerk and friction loss can be significantly re- duced by applying the proposed optimal tracking control method. 展开更多
关键词 POWERTRAIN automatic transmission shift process optimal tracking control
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An Expert System in Automatic Gauge Control for Rolling Process
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作者 智秋梅 梁启宏 侯朝桢 《Journal of Beijing Institute of Technology》 EI CAS 1995年第1期66+58-65,共9页
Beacuse the practical mathematic model of rolling process can't be built accurately,this paper established an expert system to control the rolling steels' gauge by adjusting the setup roll open, which combined... Beacuse the practical mathematic model of rolling process can't be built accurately,this paper established an expert system to control the rolling steels' gauge by adjusting the setup roll open, which combined the experience of theoreticians and operators. The system applied the expression method of rule-skeleton+rule-body', and selected an appropriate non-exact reference model and self-study algorithm. The whole system, including auxiliary routes, is designed in Borland C++. Some experiments on this system have been done, and a good result has been achieved. 展开更多
关键词 expert systems process control rolling mills /automatic gauge control
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A Study on PC/104 Embedded Automatic Balancing Control System 被引量:1
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作者 曹晰 袁洪芳 高金吉 《Journal of Donghua University(English Edition)》 EI CAS 2010年第5期665-668,共4页
In this paper,an embedded real-time control system for automatic rotor balancing was studied.Benefiting from the modular design,this system can be easily re-constituted or expanded under different working conditions.T... In this paper,an embedded real-time control system for automatic rotor balancing was studied.Benefiting from the modular design,this system can be easily re-constituted or expanded under different working conditions.The special designed hardware resists harsh environment.As an embedded application,it was very important to save system consumptions on both hardware and software,so the algorithms for unbalance vibration identification and attenuation were deduced,meantime a unified fast algorithm structure was achieved through the geometric analysis.Based on this structure,the signal processing algorithm was tested by an open data source,while the control algorithm was simulated using a basic rotor model,and then connected to a hyper gravity machine running online auto-balancing.The result confirms that the unbalancing vibration is effectively restrained. 展开更多
关键词 real time automatic balancing PC/104 vibration signal processing active control SELF-RECOVERY
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Algorithm of Dynamic Operation Process of Hydraulic Automatically Operated Canals with Constant-Downstream Level Gates
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作者 ZHANG Li-wei FENG Xiao-bo WANG Chang-de 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第6期1074-1080,共7页
On the basis of analysis the governing process of downstream water level gates AVIO and AVIS, a mathematical model for simulation of dynamic operation process of hydraulically automated irrigation canals instalIed wit... On the basis of analysis the governing process of downstream water level gates AVIO and AVIS, a mathematical model for simulation of dynamic operation process of hydraulically automated irrigation canals instalIed with AVIO and AVIS gates is presented, the main point of this rnathematical model is firstly applying a set of unsteady flow equations (St. Venant equations here) and treating the condition of gate movement as its dynamic boundary, and then deeoupling this interaction of gate movement with the change of canal flow. In this process, it is necessary to give the gateg open-loop transfer function whose input is water level deviation and output is gate discharge. The result of this simulation for a practical reach has shown it has satisfactory accuracy. 展开更多
关键词 algorithm hydraulically automatic gate AVIO gate AVIS gate downstream level control system unsteady flow dynamic process
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A 155 Mbps laser diode driver with automatic power and extinction ratio control
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作者 CHEN Xiao-fei ZOU Xue-cheng +2 位作者 LIN Shuang-xi LIU Zheng-lin JIN Hai 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第8期1346-1350,共5页
An integrated laser diode driver(LDD) driving an edge-emitting laser diode was designed and fabricated by 0.35 μm BiCMOS technology. This paper proposes a scheme which combines the automatic power control loop and te... An integrated laser diode driver(LDD) driving an edge-emitting laser diode was designed and fabricated by 0.35 μm BiCMOS technology. This paper proposes a scheme which combines the automatic power control loop and temperature com-pensation for modulation current in order to maintain constant extinction ratio and average optical power. To implement tem-perature compensation for modulation current,a novel circuit which generates a PTAT current by using the injecting base current of a bipolar transistor in saturation region,and alternates the amplifier feedback loop(closed or not) to control the state of the current path is presented. Simulation results showed that programmed by choice of external resistors,the IC can provide modu-lation current from 5 mA to 85 mA with temperature compensation adjustments and independent bias current from 4 mA to 100 mA. Optical test results showed that clear eye-diagrams can be obtained at 155 Mbps,with the output optical power being nearly constant,and the variation of extinction ratio being lower than 0.7 dB. 展开更多
关键词 Laser diode driver (LDD) automatic power control (apc Extinction ratio Temperature compensation
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DIRECT FUZZY NEURAL CONTROL FOR TRAIN TRAVELING PROCESS 被引量:2
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作者 Wang, Jing Cai, Zixing Jia, Limin 《中国有色金属学会会刊:英文版》 EI CSCD 1997年第1期147-151,共5页
DIRECTFUZZYNEURALCONTROLFORTRAINTRAVELINGPROCESS①WangJing,CaiZixing,JiaLiminResearchCenterforIntelligen... DIRECTFUZZYNEURALCONTROLFORTRAINTRAVELINGPROCESS①WangJing,CaiZixing,JiaLiminResearchCenterforIntelligentControl,CentralS... 展开更多
关键词 ATO(automatic TRAIN operation) FUZZY controller TRAIN TRAVELING process process PARTITION
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Cost Control with Modeling in Motor Housing Process
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作者 XU Run 《International Journal of Plant Engineering and Management》 2020年第1期51-64,共14页
With regards to the assembly line of cost control of Dechang company,the motor housing′s cost control of process will be necessarily appreciated.Though the supply quantity is large in a machine and the price of motor... With regards to the assembly line of cost control of Dechang company,the motor housing′s cost control of process will be necessarily appreciated.Though the supply quantity is large in a machine and the price of motor housing is cheaper,the cost control of automatic production line is significant in this respection.It is found that insufficiency power is main cause for production line failure.The cost control of equipment includes to structure wheel,conveyor and motor for benefit which also needs to be controlled in detail.Only in this way can we fundamentally resolve the main problem of high cost process.When the capital price L increases,Avc also increases too with nonlinear meantime,and Tc&Vc increase in proportion to K.Among them,the Tc increases the highest and then Vc increases lightly.Generally when labour quantity L and capital quantity K increase cost increases in proportion. 展开更多
关键词 automatic production line FLYWHEEL conveyor precision MOTOR motor housing MOLDS process of cost control modeling control
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APC在锅炉及发电控制系统的应用
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作者 贾勇 《价值工程》 2024年第22期129-131,共3页
循环流化床锅炉(Circulating Fluidized Bed Boiler,以下简称CFB锅炉)燃烧系统具有非线性、滞后性以及强耦合性等特点。常规自动化控制只适用于一定负荷条件下,而对变负荷及煤质变化等适应性差,不能满足用汽负荷变化速度。APC(Advanced ... 循环流化床锅炉(Circulating Fluidized Bed Boiler,以下简称CFB锅炉)燃烧系统具有非线性、滞后性以及强耦合性等特点。常规自动化控制只适用于一定负荷条件下,而对变负荷及煤质变化等适应性差,不能满足用汽负荷变化速度。APC(Advanced Process Control)先进过程控制系统的应用,不同于常规单回路控制,具有比常规PID控制更好的控制效果,使优化结果始终处于安全允许的范围内,确保CFB锅炉及发电系统运行的安全性,同时,根据负荷和煤质的变化,综合考虑各种干扰,优化配风和给煤,使系统有较高的运行效率。 展开更多
关键词 循环流化床锅炉 apc(先进过程控制) 协调控制
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自备发电厂机组的APC项目改造
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作者 张伟 《中国高新科技》 2024年第4期25-27,共3页
文章对新疆东方希望有色金属有限公司自备发电机组协调控制系统进行全面升级,采用引进APC控制系统的方式,以解决国产亚临界汽包机组主要参数滞后性强的问题,以及机组运行过程中扰动的多样性和不可预知性等问题,满足新形势“双碳”排放... 文章对新疆东方希望有色金属有限公司自备发电机组协调控制系统进行全面升级,采用引进APC控制系统的方式,以解决国产亚临界汽包机组主要参数滞后性强的问题,以及机组运行过程中扰动的多样性和不可预知性等问题,满足新形势“双碳”排放改造及新能源接入后电网的负荷需求。 展开更多
关键词 孤网运行 协调控制 apc(先进过程控制)项目改造 FCB 大时延特性的自动调节 “双碳”改造
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多变量预测控制软件包APC-Hiecon在液化气回收装置上的应用 被引量:3
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作者 李鸿亮 古勇 +4 位作者 王朝辉 苏宏业 褚健 王净依 徐利斌 《化工自动化及仪表》 CAS 北大核心 2001年第6期33-36,共4页
针对扬子石化公司芳烃厂液化气回收装置脱丁烷塔存在的进料波动大、操作变量多、关联性强等控制难点 ,使用多变量预测控制软件包APC Hiecon设计多变量预测控制器来实现对脱丁烷塔的平稳控制并提高分离效果 。
关键词 先进控制 多变量预测控制 apc-Hiecon 液化气回收装置 脱丁烷塔 软件包
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基于卡尔曼滤波器的液压APC系统 被引量:4
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作者 张飞 童朝南 +1 位作者 王寅虎 靖森林 《机床与液压》 北大核心 2007年第7期75-76,共2页
在液压APC(Autom atic Position Control)系统中,由于存在控制干扰和测量噪声,为了达到控制精度,通常采取低通滤波,但效果不甚理想。为此,本文提出了一种基于卡尔曼滤波器的控制方法,该方法采用时域上的递推算法进行数字滤波处理,通过... 在液压APC(Autom atic Position Control)系统中,由于存在控制干扰和测量噪声,为了达到控制精度,通常采取低通滤波,但效果不甚理想。为此,本文提出了一种基于卡尔曼滤波器的控制方法,该方法采用时域上的递推算法进行数字滤波处理,通过仿真和实际应用证明该方法使APC系统运行平稳,大大提高了APC系统的精度。 展开更多
关键词 液压伺服 自动位置控制 卡尔曼滤波器
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轧机液压APC系统的自抗扰控制研究 被引量:2
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作者 陈至坤 镇维 张瑞成 《机床与液压》 北大核心 2008年第4期119-121,124,共4页
考虑到液压APC系统存在不确定负载干扰和未建模动态的特点,首先建立了液压APC系统的模型,将不确定性负载扰动和未建模动态视为一个综合扰动项,然后利用扩张状态观测器(ESO)对其进行观测和补偿,并基于自抗扰控制技术设计了一个不依赖于... 考虑到液压APC系统存在不确定负载干扰和未建模动态的特点,首先建立了液压APC系统的模型,将不确定性负载扰动和未建模动态视为一个综合扰动项,然后利用扩张状态观测器(ESO)对其进行观测和补偿,并基于自抗扰控制技术设计了一个不依赖于对象模型的控制器。仿真结果表明:该控制器不仅有效地抑制了不确定负载扰动对系统的影响,同时对受控对象模型参数的变化也具有较强的鲁棒性。 展开更多
关键词 液压自动位置控制 扩张状态观测器 自抗扰控制器 鲁棒性
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模式飞剪的APC系统 被引量:2
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作者 葛延津 《钢铁》 CAS CSCD 北大核心 2002年第10期60-64,共5页
介绍了不同于回转剪的模式飞剪。给出了模式飞剪 APC系统的结构 ,推导出模式飞剪 APC系统的控制算法及位置 ,给定信号产生原理及算法。绘出了模式飞剪与带钢行进中的路径波形。给出了 APC系统实际的定尺精度等运行结果。带钢被剪端口光... 介绍了不同于回转剪的模式飞剪。给出了模式飞剪 APC系统的结构 ,推导出模式飞剪 APC系统的控制算法及位置 ,给定信号产生原理及算法。绘出了模式飞剪与带钢行进中的路径波形。给出了 APC系统实际的定尺精度等运行结果。带钢被剪端口光滑、整齐。该 展开更多
关键词 模式飞剪 位置自动控制系统 apc 定尺剪切
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先进控制技术(APC)在大型延迟焦化装置的应用 被引量:5
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作者 王赓 《中外能源》 CAS 2018年第9期76-85,共10页
先进控制技术(APC)目前正在复杂化程度高的流程工业中普及应用。Aspen公司的DMCplus技术采用动态矩阵控制算法(DMC)作为核心算法,其基本特征包括预测模型、滚动优化、反馈校正,为典型的多变量模型预测控制算法。某炼化公司延迟焦化... 先进控制技术(APC)目前正在复杂化程度高的流程工业中普及应用。Aspen公司的DMCplus技术采用动态矩阵控制算法(DMC)作为核心算法,其基本特征包括预测模型、滚动优化、反馈校正,为典型的多变量模型预测控制算法。某炼化公司延迟焦化装置设计加工规模为420×104t/a,采用两炉四塔工艺路线,采用Aspen公司DMCplus先进控制技术设计了4个先进控制器:加热炉支路平衡控制器、加热炉炉效率控制器、主分馏塔控制器、吸收稳定控制器。先进控制器投运后,能自动过渡焦炭塔预热、切换等过程,并抵御这些过程中带来的干扰,保证24h不摘除,减轻劳动强度;平稳装置操作,大部分工艺参数点标准偏差降低20%以上,关键被控变量的标准偏差降低30%以上;提高加热炉炉效率,优化分馏塔温度分布,并提高高价值产品产率,优化了吸收稳定装置的流量和温度分布,节能降耗;提供相应软测量预测,软仪表计算值与化验值之间的偏差满足工艺要求。每年创造经济效益2600多万元。 展开更多
关键词 先进控制 延迟焦化 模型预测控制 动态矩阵控制
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先进控制技术(APC)在汽油加氢装置的开发应用
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作者 王赓 《中外能源》 CAS 2018年第6期61-69,共9页
以多变量模型预测控制为主要特征的先进控制技术(APC)是流程工业中一种获取更高经济效益的方法,目前广泛应用且具有代表性的先进控制技术有Aspen公司的多变量动态预估控制技术(DMCplus)和Honeywell公司的鲁棒多变量预估控制技术(Pr... 以多变量模型预测控制为主要特征的先进控制技术(APC)是流程工业中一种获取更高经济效益的方法,目前广泛应用且具有代表性的先进控制技术有Aspen公司的多变量动态预估控制技术(DMCplus)和Honeywell公司的鲁棒多变量预估控制技术(Profit Controller)。汽油加氢装置所加工的汽油性质差别很大,给装置平稳控制和产品质量保证带来困难。某汽油加氢装置设计加工能力为90×10^4t/a,原料性质变化及加工量调整频繁,反应单元耦合性强,反应炉负荷高。采用Aspen DMCplus技术设计了一个先进控制器,即汽油加氢控制器,包括切割塔、切割炉及反应炉、反应汽提三个子控制器,分别控制汽油加氢装置切割单元、切割塔重沸炉及反应炉、反应及分馏单元。先进控制器投运后,在提高装置运行平稳性和安全性的同时,降低了产品辛烷值损失,保障了反应炉运行安全,降低了操作劳动强度,节能降耗,每年可以产生直接经济效益361.8万元。 展开更多
关键词 汽油加氢 先进控制 模型预测控制 动态矩阵控制
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APC自动纠偏装置试验研究
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作者 谢咏山 《重型机械》 1997年第1期21-23,共3页
武钢硅钢厂退火生产线经常发生因带钢跑偏造成断带事故。在加热炉出口处增设一套APC自动纠偏装置,经三年运行考核,使用良好,消除了事故。
关键词 apc 自动纠偏 光电开关 退火生产线 程序控制器
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电动APC系统在中板轧机压下装置中的应用 被引量:1
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作者 李智慧 曾庆亮 《轧钢》 2004年第4期46-47,共2页
为了解决手动压下难以准确定位问题 ,采用电动APC实现了压下辊缝自动控制 ,介绍了电动APC控制系统的组成及在中板轧制过程中实现的方法 ,系统投入后因定位精度提高 ,有效地控制了异板差 ,保证了负偏差轧制 。
关键词 中板轧制 自动控制 电动apc 压下装置
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APC+控制系统在聚乙烯装置上的应用 被引量:1
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作者 姜南 慕永明 《炼油与化工》 2013年第4期41-43,63,共3页
先进控制系统在石化装置中已大量使用。文中阐述了UNIPOL APC+系统在大庆石化公司塑料厂全密度装置的应用情况,对比分析了其与传统DCS控制的优势。
关键词 apc+ 聚乙烯装置 先进控制 气相法
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Control structure comparison for three-product Petlyuk column 被引量:1
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作者 Shengkun Jia Xing Qian +1 位作者 Xigang Yuan Sigurd Skogestad 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第8期1621-1630,共10页
The focus of this paper is to investigate different control structures(single-loop PI control) for a dividing wall(Petlyuk) column for separating ethanol, n-propanol and n-butanol. Four control structures are studied.... The focus of this paper is to investigate different control structures(single-loop PI control) for a dividing wall(Petlyuk) column for separating ethanol, n-propanol and n-butanol. Four control structures are studied. All the results are simulations based on Aspen Plus. Control structure 1(CS1) is stabilizing control structure with only temperature controllers. CS2, CS3 and CS4, containing also composition controllers, are introduced to reduce the steady state composition deviations. CS2 adds a distillate composition controller(CCDB) on top of CS1. CS3 is much more complicated with three temperature-composition cascade controllers and in addition a selector to the reboiler duty to control the maximum controller output of light impurity composition control in side stream and bottom impurity control in the prefractionator. CS4 adds another high selector to control the light impurity in the sidestream. Surprisingly, when considering the dynamic and even steady state performance of the proposed control structures, CS1 proves to be the best control structure to handle feed disturbances inserted into the three-product Petlyuk column. 展开更多
关键词 Distillation columns automatic process control Computer-aided control system design Petlyuk columns
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