Petrochemical industry plays an important role in the development of the national economy. Purified terephthalic acid(PTA) is one of the most important intermediate raw materials in the petrochemical and chemical fibe...Petrochemical industry plays an important role in the development of the national economy. Purified terephthalic acid(PTA) is one of the most important intermediate raw materials in the petrochemical and chemical fiber industries. PTA production has two parts:p-xylene(PX) oxidation process and crude terephthalic acid(CTA) hydropurification process. The CTA hydropurification process is used to reduce impurities, such as 4-carboxybenzaldehyde, which is produced by a side reaction in the PX oxidation process and is harmful to the polyester industry. From the safety and economic viewpoints, monitoring this process is necessary. Four main faults of this process are analyzed in this study. The common process monitoring methods always use T^2 and SPE statistic as control limits. However, the traditional methods do not fully consider the economic viewpoint. In this study, a new economic control chart design method based on the differential evolution(DE) algorithm is developed. The DE algorithm transforms the economic control chart design problem to an optimization problem and is an excellent solution to such problem. Case studies of the main faults of the hydropurification process indicate that the proposed method can achieve minimum profit loss.This method is useful in economic control chart design and can provide guidance for the petrochemical industry.展开更多
Rahim and Banerjee [1] developed a general model for the optimal design of x-control charts. The model minimizes the expected cost per unit time. The heart of the model is a theorem that derives the expected total cos...Rahim and Banerjee [1] developed a general model for the optimal design of x-control charts. The model minimizes the expected cost per unit time. The heart of the model is a theorem that derives the expected total cost and the expected cycle length. In this paper an alternative simple proof for the theorem is provided based on mathematical induction.展开更多
提出了一种简单、有效的用以辅助设计单值控制图的方法.该方法综合考虑了样本容量、采样频率以及控制图控制限等3个参数，引入了平均生产产量APQ（average production quantity）作为衡量控制图性能的标准.基于APQ构建了一个数...提出了一种简单、有效的用以辅助设计单值控制图的方法.该方法综合考虑了样本容量、采样频率以及控制图控制限等3个参数，引入了平均生产产量APQ（average production quantity）作为衡量控制图性能的标准.基于APQ构建了一个数学模型，该数学模型以采样率和最大错判概率为已知输入来计算出最优的控制图设计参数，从而满足优化设计的目的.该方法包含了涉及控制图设计的所有关键元素，但是它比控制图的经济和半经济设计模型简单易用.展开更多
基金supported by the National Natural Science Foundation of China (61422303, 21376077)Fundamental Research Funds for Central Universities
文摘Petrochemical industry plays an important role in the development of the national economy. Purified terephthalic acid(PTA) is one of the most important intermediate raw materials in the petrochemical and chemical fiber industries. PTA production has two parts:p-xylene(PX) oxidation process and crude terephthalic acid(CTA) hydropurification process. The CTA hydropurification process is used to reduce impurities, such as 4-carboxybenzaldehyde, which is produced by a side reaction in the PX oxidation process and is harmful to the polyester industry. From the safety and economic viewpoints, monitoring this process is necessary. Four main faults of this process are analyzed in this study. The common process monitoring methods always use T^2 and SPE statistic as control limits. However, the traditional methods do not fully consider the economic viewpoint. In this study, a new economic control chart design method based on the differential evolution(DE) algorithm is developed. The DE algorithm transforms the economic control chart design problem to an optimization problem and is an excellent solution to such problem. Case studies of the main faults of the hydropurification process indicate that the proposed method can achieve minimum profit loss.This method is useful in economic control chart design and can provide guidance for the petrochemical industry.
文摘Rahim and Banerjee [1] developed a general model for the optimal design of x-control charts. The model minimizes the expected cost per unit time. The heart of the model is a theorem that derives the expected total cost and the expected cycle length. In this paper an alternative simple proof for the theorem is provided based on mathematical induction.
文摘提出了一种简单、有效的用以辅助设计单值控制图的方法.该方法综合考虑了样本容量、采样频率以及控制图控制限等3个参数，引入了平均生产产量APQ（average production quantity）作为衡量控制图性能的标准.基于APQ构建了一个数学模型，该数学模型以采样率和最大错判概率为已知输入来计算出最优的控制图设计参数，从而满足优化设计的目的.该方法包含了涉及控制图设计的所有关键元素，但是它比控制图的经济和半经济设计模型简单易用.
