原油常减压蒸馏工艺的动态仿真

为了更好的掌握原油常减压蒸馏系统在开停车过程和正常操作时的工况、预测事故状态,实现准确无误的控制过程.对某厂原油常减压蒸馏过程进行了仿真.首先对流程中的蒸馏装置初馏塔、常压塔、减压塔进行分析.为建立精确的模型,考虑了塔的流体力学特性和多个精馏塔之间的相互作用的影响,并根据物料衡算、能量衡算、相平衡等,建立了蒸馏装置的数学模型,并由模型的形式选取适当的求解方法.仿真结果表明,达到稳定状态的结果能正确地反映装置实际工况的运行情况,为实际工况中的工艺设计和系统优化,提供了重要的理论依据.工艺仿真系统已成功应用于常减压装置的开停车过程和正常操作等培训内容.     

柴油加氢反应过程的动态仿真

针对国内石化行业的柴油加氢精制工艺,重点研究了加氢精制反应器.主要目的在于通过建立柴油加氢反应器的动态模型,为开发出柴油加氢工艺的动态仿真软件提供可靠的依据.在反应器模型分析过程中,采用新的思路,通过对反应器类型和反应网络的分析,确定了反应动力学模型,并建立了物料衡算、能量衡算等方程,进而建立了反应器的动态数学模型.模型计算结果与实际工艺值相符,准确地反应了装置正常运行时的状态,说明了数学模型的正确性.工艺仿真系统的建立,成功地应用于国内石化企业员工的培训工作,效果显著.     

精馏过程动态仿真建模

精馏过程的模型化与仿真在化工操作和工艺设计中具有重要的意义。对精馏塔进行动态数学模型的建立与仿真,不仅可以研究精馏过程在不同工况下的变化情况,而且还可以用于精馏塔的优化控制,进而提高精馏过程的生产效益。本文针对精馏塔操作过程,建立了基于平衡级假设和非平衡级假设的精馏过程动态机理数学模型,并对平衡级假设的模型进行了动态模拟。该模型从机理分析入手,进行合理的简化,模型的计算时间大大的缩短,从而使模型具有比较广泛的实用性。该模型采用的动态数学模型为METSH(质量平衡方程、相平衡方程、塔板效率方程、摩尔分数归一化方程、能量平衡方程)方程,通过计算METSH方程,可以模拟出精馏塔内温度、汽相流量、液相流量、汽相组分以及液相组分的变化趋势。通过仿真结果可以看到,该模型比较准确的预测了精馏塔中各个操作参数的动态趋势,与实际情况基本一致,其稳态结果与实际情况也基本吻合。该模型对于仿真培训及精馏过程的控制分析具有较高的理论研究意义和实际应用价值。     

飞机环境控制系统的仿真研究

以飞机环境控制系统(AECS)为研究对象,建立了系统各主要部件的数学模型,对系统进行丁仿真研究。采用模块化结构的方法,利用Matlab／Simulink建立各部件的仿真模块并构成系统进行仿真研究,对系统在扰动下的动态响应进行了仿真分析。仿真结果表明所建模型具有较高的精度,为研究飞机环境控制系统的动态性能提供了新的实现途径。     

加氢催化剂器内预硫化动态仿真研究与应用

加氢催化剂预硫化过程是重油催化裂化、催化加氢、催化重整工艺的优化过程,决定着产品质量和产量。由于预硫化过程的复杂性和动态性,在实际生产中难以控制,提出建立数学模型进行计算。但因国内预硫化过程动态研究比较少,所以先对预硫化反应器进行深入分析,以固定床反应器为基础,建立了机理性较强的预硫化反应器模型。包括反应动力学方程,质量衡算方程,能量衡算方程,相平衡方程等。采用适当的数值计算方法进行动态仿真计算,结果表明与实际相符,硫化温度曲线与设计曲线非常相近。采用上述方法建立仿真软件已应用到实际生产中,并对员工培训起到了良好效果。     

Gsp气化炉建模与动态模拟

为了能够更好的模拟Gsp煤气化炉,建立了新的气化炉模型。Gsp煤气化炉内部反应较为复杂,温度、压力较高难以模拟,为了对气化炉建立数学模型并且对生产工艺进行动态模拟,通过对煤气化炉装置物料流动方式的分析,结合煤气化反应的动力学、物料衡算和能量衡算,简化反应过程的次要因素,最终用通用化工动态流程模拟优化软件平台建立了气化炉反应器的串联全混流模型,并且选用四阶龙格-库塔法进行求解计算。反应器动态模拟的数值结果与实测值相比较,发现通过优化计算的结果可以把误差控制在1%以内,证明建立的数学模型能够很好地模拟工艺流程,为模拟Gsp煤气化炉提供了一种新的思路。     

茂金属聚乙烯气相开车过程动态模拟

开车过程作为聚乙烯装置运行的初始环节,对废料量、产品质量等有重要影响,而关于茂金属聚乙烯气相聚合开车过程动态模拟的研究比较少。本文以gPROMS为建模工具建立了气相流化床反应器中乙烯、1-丁烯在茂金属催化剂催化下共聚的动态模型,包括反应动力学、物料衡算、热量衡算等,并利用该模型模拟了乙烯气相聚合开车过程。模拟结果显示,开车过程所用时间、达到稳态后的各项指标与实际装置可以很好地吻合,聚乙烯分子量分布较窄也符合茂金属催化剂单一活性位的特点,表明建立的模型是准确有效的,可用于开展进一步的研究工作。     

石脑油在SRT-IV型工业炉清洁辐射管中裂解的数学模拟

为了更准确模拟石脑油工业裂解实际生产情况 ,提出基于实际装置的炉膛烟气温度分布的二次函数形式和反应管路的局部压降计算思想。根据Kumar提出的分子反应动力学模型 ,关联质量、热量和动量衡算关系式 ,建立了SRT IV型工业裂解炉辐射段的清洁管工艺裂解数学模型。模拟计算结果表明 ,裂解炉管出口各项指标与工厂现场标定数据吻合较好     

甲醇低压羰基化制醋酸反应器仿真

在甲醇低压羰基化制醋酸反应器内,化学反应与流体力学状况非常复杂.因此,反应器机理模型的建立是开发全流程仿真机过程中必须解决的问题.文中对甲醇低压羰基化制醋酸反应机理与动力学进行j,深入研究,通过合理的简化假设以及物料衡算、热量衡算建立了醋酸反应器的机理模型.合理的简化假设极大地提高了模型求解的速度,满足了实时动态仿真的要求.仿真结果表明,达到稳态时的结果能很好地逼近实际值,动态过程也能很好地反映实际过程的变化趋势,并能对非正常工况进行仿真.该模型对醋酸反应器动态特性与控制方式的研究以及全流程仿真机的开发具有重要意义.该模型已成功应用于某化工厂的醋酸反应器全流程仿真机,取得了满意效果.     

甲醇/水二元间歇精馏塔的建模与先进控制

应用动态物料平衡和相平衡等机理建模法,建立了一套甲醇／水二元间歇精馏塔实验装置的数学模型。以Matlab为平台,开发了该模型计算软件。设计了塔顶甲醇浓度比例积分反馈推断控制、多个温度联合加醛反馈控制、塔顶甲醇浓度反馈增益自调整控制等控制策略。并应用基于状态空间模型的模型预测控制算法,推导了间歇精馏塔多个浓度反馈时的模型预测控制策略。对这些先进控制策略进行了仿真试验研究,仿真结果被用于指导间歇精馏控制实验,获得了满意的控制结果。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。