工厂供电系统故障诊断专家系统的设计

工厂供电系统的安全运行对工业企业来说至关重要 ,特别是对于化工企业 ,如何快速判断和切除故障非常关键。介绍了利用专家系统技术开发供电系统故障诊断系统的结构特点、主要功能 ,重点阐述了系统中推理机的构造、知识库的描述及网络图形显示、模拟倒闸操作等功能的实现。该系统是用VC ++开发成功的 ,并对用VC ++实现知识的框架结构表达做了详细的说明     

一个用于化工分离过程合成设计的专家系统

开发了一个基于模糊匹配推理策略的专家系统，可用于分离技术的选择和分离设备的排序。该专家系统首先建立一个可容纳多种设计方案的宏结构，模糊匹配策略驱动一个平行搜索算法，最终产生一集优化的设计方案。     

Esterification effect on the recovery of vitamin E from palm oil refining residues by molecular distillation

Waste edible oils are an alternative source of high-value natural compounds. Vitamin E can be recovered from palm oil refining residues by molecular distillation. However, the presence of other lipophilic molecules compromises the selective separation of vitamin E. Esterification of the free fatty acids can enhance the selective separation of vitamin E by molecular distillation, but the conditions for carrying out the reaction need to be investigated to simultaneously ensure the conversion of free fatty acids and the reduction of vitamin E losses. Thus, this study investigated the effect of the esterification of the industrial waste on the recovery of vitamin E by molecular distillation. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and analysis for fats and oils preconized by the American Oil Chemists' Society (AOCS) were used in the characterization of the industrial waste. Determination of the best condition to carry out the reaction was obtained by a central composite rotational design (CCRD) using the response surface methodology (RSM) and the desirability profile. The results showed that the best condition for the esterification was at 64°C, 213 min, 2 wt.% sulphuric acid, and a 10/1 methanol/free fatty acids molar ratio. This reaction condition achieved 97.9% conversion of free fatty acids and less than 3% of vitamin E loss. The esterification promoted concentration of vitamin E in the residue stream (145.4%) and reduction in the distillate stream (87.8%). Therefore, the obtained results presented a suitable route to obtaining vitamin E concentrate and adding value to an industrial residue.     

基于污水处理工艺专家系统的研究

讨论了如何构建污水处理工艺专家系统,该系统主要采用正向推理模糊机制,并用规则子树的形式将知识组织向用户公开,便于用户使用和对系统维护升级.     

合成氨装置净化系统"瓶颈”分析

介绍利用第10版ASPENPLUS流程模拟软件对合成氨装置净化系统进行模拟计算来寻找其"瓶颈”的主要过程及方法.给出消除"瓶颈”的措施及该措施的实际实施情况和效果.     

The development of a deep knowledge diagnostic expert system using fault tree analysis information

In this paper a diagnostic Knowledge Based Expert System (KBES) prototype for a nuclear Auxiliary Boiler Feed System (ABFS) was developed. A commercial Expert System shell accesses heuristic production rules to quickly resolve the majority of common faults. Supplementing this are a series of C functions which access the Fault Tree data base previously developed during the licensing process. These functions perform diagnostics, give detailed explanations of failure mechanisms, and identify system failure risks through examination of cut sets. The capture of both heuristic and Fault Tree information has resulted in a more exhaustive diagnostic tool with a domain of application unrestricted by the limitations of previous operator experience.     

Testing and validation of an expert system for making liming decisions

Computer-based technologies are becoming increasingly important in translating the wealth of agricultural research information into forms that can be used by extension workers. The Acidity Decision Support System (ADSS) is a computer-based expert system that diagnoses and corrects Al-toxicity problems on highly-weathered mineral soils. The objectives of this work were to use published data to evaluate and provide recommendations to improve the ADSS knowledge base. The relative yield-Al saturation curves used by ADSS satisfactorily predict the results of field experiments for maize and soybean, but needs to be improved for rice and cassava. Curves used by ADSS for all four crops should, however, be updated to represent the research data better. Insufficient data were obtained to evaluate other crops satisfactorily. ADSS predicted that more lime would be needed to reduce soil Al saturation than was actually needed. This can be corrected by changing the value of the liming factor (LF) constant in ADSS to better represent the capability of liming materials to neutralize soil Al in the field. ADSS also predicted more response of rice and soybean to lime in on-farm experiments than occurred in practice, although there was a correlation between predicted and actual relative yield for soybean. ADSS should indicate the chances that the predicted relative yield response will not occur because of factors other than liming, under normal farming conditions. The Smyth and Cravo equation provides a reasonable estimate, in lieu of alternatives, of the change in soil Al saturation for up to five years after liming.     

模糊推理方法在控制系统故障诊断中的应用研究

一种不依赖硬件和环境的全软件解决方案,直接利用输入信号和反馈信号的测量分析,经模糊变换获得信号特征模糊变量,通过扫描信号特征量的超限情况,调用相关推理规则运算求解得到控制系统的故障诊断信息。开发的应用软件已用于工业实际系统。     

A hybrid expert-procedural system for the design of reverse-osmosis desalination plants

The problem of computer-aided design and synthesis of a reverse-osmosis desalination plant is presented. A hybrid expert-procedural system has been developed that deal with the synthesis problem at two levels of abstraction. The expert part of the system uses qualitative data, and through heuristics, makes decisions about the structure of the plant. The procedural part of the system uses the decisions of the expert part as a basis for detailed design and optimisation. The heuristics used in the expert part come from experienced designers and from proposals of membrane manufacturers. The detailed calculations are based on mass balance equations and correlations for the permeators. The system developed can be used to propose a reverse-osmosis plant structure and to perform detailed calculations for possible design scenarios envisaged by the user. A case study on such a plant is also given and shows how the expert system handles the design problem of a reverse osmosis desalination plant.     

干燥机支撑系统和传动系统故障分析及对策

根据复合肥装置中干燥机托轮支撑系统轮轴及传动系统减速器高速轴断裂状况,分析其故障原因,提出解决的对策与方法。     

乙烯装置急冷油系统存在问题的分析

某些乙烯装置的急冷油系统操作数据与设计数据偏离较远，说明设计上存在问题，应从工艺流程设计和模拟计算入手，找到准确的设计方法。     

乙烯装置急冷油减粘系统运行分析

通过对乙烯装置各种急冷油减粘系统的比较和运行状况分析，找出急冷油减粘系统存在的问题并提出改进办法，使急冷油减粘系统稳定运行，满足急冷油塔高负荷生产需要。     

基于模糊神经网络的变压器局部放电小波奇异性故障诊断

变压器故障中除油变质劣化之外,另一种重要故障即为局部放电。将小波奇异性检测理论与模糊神经网络结合起来,对变压器局部放电时的信号先利用小波奇异性检测理论求出奇异性指数作为故障诊断的特征参数,然后将其模糊化作为神经网络的输入,输出为各种故障的隶属度,进而判断变压器存在何种故障的可能性。仿真结果表明此方法用于变压器局部放电故障诊断是行之有效的。     

故障树分析方法在提升机系统中的应用

分析经典故障树分析方法,提出了基于故障率为模糊数的故障树分析方法。针对提升机应用实例,将故障率转化为三角模糊数来计算,通过最大隶属度去模糊化处理,计算得到系统的可靠度与时间的变化曲线图,证明了应用模糊数学集合理论对系统进行基于故障率为模糊数的故障分析,可以较好地克服经典方法难于精确赋值等缺点。     

Alum as a heterogeneous catalyst for the transesterification of palm oil

Alum has been taken beyond its traditional roles as a water treatment chemical and a confectionary additive to a new role as a catalytic precursor in biodiesel production. Its catalytic potentials were empirically proved via palm oil transesterification with methanol and application of solid state instrumental characterization techniques. The catalyst was very clean, efficient, simple and cheap to produce, and could be clearly separated from the reaction products. When the reaction was carried out under the conditions of catalyst to oil ratio of 7.09 wt%, reaction time of 12 h and temperature of 170 °C, methanol to oil molar ratio of 18:1 and catalyst preconditioned at 550 °C, the yield of fatty acid methyl ester (FAME) obtained was 92.5 wt%.     

水系统集成技术在甲醇厂的应用

水系统集成技术是把整个工业用水系统作为一个整体来看待,并考虑水质、水量的分配,从而使系统用水的重复利用率达到最大,同时废水排放量最小。甲醇企业是用水和废水排放的大户,将水系统集成技术应用于甲醇工业,具有重要意义。文中结合水系统集成技术的工业应用现状,总结了水系统集成技术在工业企业中应用的一般步骤,具体分为以下几步:选定目标系统,明确水源水阱,确定关键污染物组分和极限进出口浓度,生成初始网络和用水网络调优。并以某甲醇厂简化的用水系统为实例,采用文中所提出的一般应用步骤,对用水网络进行了优化,获得了新鲜水节水率达34.5%的节水效果。     

Effect of altitude and palm oil biodiesel fuelling on the performance and combustion characteristics of a HSDI diesel engine

Altitude above sea level and fuel’s chemical and physical nature affect engine performance and combustion characteristics. In this work, a combustion diagnosis model including exergy analysis was applied to a turbocharged (TC) automotive diesel engine fuelled with neat palm oil biodiesel (B100) and No. 2 diesel fuel (B0). Tests were performed under steady state operating conditions, at two altitudes above sea level: 500 and 2400 m. Biodiesel fuelling and altitude had an additive effect on the advance in injection and combustion timings. The duration of the premixed combustion stage increased with altitude and decreased with biodiesel. When B100 was used, the transition between this stage and the diffusion stage was practically suppressed. As altitude increased, biodiesel fuelling led to shorter combustion duration, and higher in-cylinder pressures and fuel-air equivalence ratios. Brake thermal efficiency decreased with altitude for both fuels, but in a greater extent for B0. For all fuels and altitudes, exergy destruction rose sharply when combustion started, indicating that this process was the main source of irreversibilities. At both altitudes, the cumulative exergy destruction was higher for B100 due to its earlier and faster combustion process. Some of the results obtained in this work indicate that palm oil biodiesel fuelling can lead to a better engine performance at high altitudes.     

基于物联网和故障树技术的阳极保护远程系统介绍

介绍了基于物联网和故障树技术的阳极保护远程监控、预警及故障诊断系统的原理、结构。利用物联网技术和故障树分析技术,对远端在役阳极保护设备进行监控,并实施对设备运行状态评估、隐患预警及故障诊断等功能。它可快速准确排除设备故障、降低设备故障率和维护/维修的时间及成本,极大提升了阳极保护设备维护管理水平。     

HSE管理体系在石化装置的应用

本文对化工厂易发事故进行了分析,并将HSE管理体系应用于管理中,提出了应急预案模式,保证了安全生产。     

乙烯装置急冷油粘度增长机理的研究

对乙烯裂解装置中急冷油粘度增长的原因及反应机理进行了分析探讨,并提出了急冷油减粘剂的开发方向。