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991.
介绍了基于FPGA的高温热流传感器信号采集存储系统.系统使用XC2S50作为主控制芯片,实现了对高温热流传感器测量信号和温度信号两路模拟量数据的采集,并将获得的数据混合编帧存储.实验证明,该系统能够完整获得热流传感器的测试信号及其温度信号,具有电路简单、采集精度高、稳定性高等特点.  相似文献   
992.
申开旭 《云南化工》2011,38(4):62-65
依据《评审准则》和云南省水环境监测中心质量体系文件———《程序文件》YWEC/CX-2010、《质量手册》的要求,就实验室的环境监测设备量值溯源及确认,期间核查,使用,维护等方面进行归纳和总结,以便进一步确保管理体系持续有效进行。  相似文献   
993.
新型钻井监测仪软件系统设计   总被引:2,自引:0,他引:2  
尹存涛 《化工机械》2011,38(3):305-308,312
介绍了钻井参数监测软件的结构体系、数据流程以及功能模型,并论述了软件系统中所处理的几个关键技术.  相似文献   
994.
The main aim of this work is to investigate the effect of CO2 and N2O under pressure in aqueous solution - both on-line and in real-time. In particular, the paper presents the kinetics of pH behaviour of either slightly buffered minimal medium (MM) or non-buffered solution (Ringer solution) during high-pressure treatment at 5, 30 and 60 bar at 25 °C.An innovative spectrophotometric approach has been developed: an optical fiber conducted the inlet signal of a light source into the high-pressure reactor, while another fiber conducted the outlet signal to a spectrometer, thus, obtaining measurements on-line and real-time.CO2 treatment resulted in a pH decrease down to 3.0 in Ringer solution with the equilibrium being reached after 800 s, while the slightly buffered MM allows only for a decrease down to 4.5 with equilibrium being reached after slightly more than 40 s at 60 bar.N2O treatment, as expected, did not lead to any acidification of the treated medium at any conditions tested.Furthermore, a mathematical model describing both the solubilization kinetics of CO2 and in aqueous solution and the decrease of extracellular pH has been implemented. This model may easily be applied to different reactor configurations. The theoretical results and the goodness of the fit has been verified using the experimental results showing a good accuracy of the complex phenomena with a simplification that is of vital relevance for technical processes.  相似文献   
995.
In this article, we utilize the concept of partial Granger causality to study the penicillin production process under several operating conditions. We propose a graph-theoretic template (causal network) based method for intelligent process monitoring. We validate our results with the aid of existing knowledge and available literature. The proposed method is quite general and can be extended to analyze several physical, chemical or biological systems.  相似文献   
996.
In this article, we review and discuss algorithms for adaptive data-driven soft sensing. In order to be able to provide a comprehensive overview of the adaptation techniques, adaptive soft sensing methods are reviewed from the perspective of machine learning theory for adaptive learning systems. In particular, the concept drift theory is exploited to classify the algorithms into three different types, which are: (i) moving windows techniques; (ii) recursive adaptation techniques; and (iii) ensemble-based methods. The most significant algorithms are described in some detail and critically reviewed in this work. We also provide a comprehensive list of publications where adaptive soft sensors were proposed and applied to practical problems. Furthermore in order to enable the comparison of different methods to standard soft sensor applications, a list of publicly available data sets for the development of data-driven soft sensors is presented.  相似文献   
997.
Environmental metric software can be used to evaluate the sustainability of a chemical based upon data from the chemical process used to manufacture it. An obstacle to the development of environmental metric software for use in chemical process modeling software has been the inability to obtain information about the process directly from the model. There have been past attempts to develop environmental metrics that make use of the process models, but there has not been an integrated, standardized approach to obtaining the process information required for calculating metrics. As a result, environmental evaluation packages are largely limited to use in a single simulation package, further limiting the development and adoption of these tools.This paper proposes a standardized mechanism for obtaining process information directly from a process model using a strongly integrated interface set, called flowsheet monitoring. The flowsheet monitoring interface provides read-only access to the unit operation and streams within the process model, and can be used to obtain the material flow data from the process streams. This material flow data can then be used to calculate process-based environmental metrics. The flowsheet monitoring interface has been proposed as an extension of the CAPE-OPEN chemical process simulation interface set.To demonstrate the capability of the flowsheet monitoring interfaces, the US Environmental Protection Agency (USEPA) WAste Reduction (WAR) algorithm is demonstrated in AmsterCHEM's COFE (CAPE-OPEN Flowsheeting Environment). The WAR add-in accesses the material flows and unit operations directly from the process simulator and uses flow data to calculate the potential environmental impact (PEI) score for the process. The WAR algorithm add-in is included in the latest release of COCO Simulation Environment, available from http://www.cocosimulator.org/.  相似文献   
998.
王绍楠  袁东 《广东化工》2011,38(1):177-178,174
色谱-质谱联用技术是现代分析测试技术的重要研究方向。经过几十年的发展,它已经在环境监测领域发挥了巨大的作用。文章介绍了该技术在水体监测、空气监测和土壤监测方面的应用。  相似文献   
999.
组态王在全混釜监控系统中的设计与应用   总被引:1,自引:0,他引:1  
全混釜监控系统主要用于监控全混釜运行流程,对其反应过程进行实时监控并作出及时的干预.在程序开发设计各个模块的基础上,在组态王上实现全混釜温度及压力的采集、处理和实时监控,并完成报警、数据记录、报表生成及打印等功能.系统集控制设计、数据库技术、计算机网络连接技术于一体,使用组态王软件实现友好的人机界面,可扩展性好,可靠性...  相似文献   
1000.
叶丽 《化工技术与开发》2011,40(9):76-78,69
介绍锑白炉生产过程自动化控制系统设计,通过分析锑白炉生产过程各检测及控制参量的要求,进行智能模块系统及生产现场摄像监控系统配置,实现集散式监控、报警、录像、智能化检索回放及系统管理等诸多功能.  相似文献   
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