Process monitoring method based on correlation variable classification and vine copula

Chemical processes are becoming increasingly complicated, leading to an increase in process variables and more complex relationships among them. The vine copula has a significant advantage in portraying the dependence of high-dimensional variables. However, as the dimensions increase, the vine copula model incurs a high computational load; such pressure greatly reduces model efficiency. Relationships among variables in the industrial process are complex. Different variables may be strongly or weakly associated or even independent. This paper proposes a process monitoring method based on correlation variable classification and vine copula. The weighted correlation measure is first used to divide variables into a correlated subspace and weakly correlated subspace. Then, two vine structures, C-vine and D-vine, are applied to the correlated and weakly correlated subspaces, respectively. This method takes advantage of C-vine for correlated variables and the flexibility of D-vine for weakly correlated variables. Finally, comprehensive statistics are established based on different subspaces. Monitoring results of the numerical system and the Tennessee Eastman process demonstrate the effectiveness and validity of the proposed method.     

华南植物园藤本植物专类园规划设计

专类园是一种强调专类植物收集、展示和植物造 景的园林形式，在植物园建设中具有重要地位。藤本植物因 其独特的观赏特征、生长习性及生态效应，近年已成为城市 园林绿化的重要造景材料。在分析华南植物园藤本植物专类 园建设背景、园址概况的基础上，结合其功能定位，提出了 科学性、功能性、地域性、艺术性及以人为本的规划原则； 确定了“一轴、三线、三点、五片区”的总体规划布局。在 文化线的园林构图及造景上，重点阐述了三大主题景观节 点——帷幄疏影、西关居、文昌亭的设计理念及其园林建筑 风格，探讨了岭南传统建筑、小品及文化在构建地域特色园 林景观中的作用；在植物线的园林造景上，简介了各景区的 植物布置方式及组景模式；在科普旅游线的组织上，介绍了 园区的园林小品造景意境及科普设施布置形式，以期为中国 藤本植物专类园建设提供参考。     

Trypsin inhibitor activity in vegetative tissue of sweet potato plants and its response to heat treatment

Trypsin inhibitor activity (TIA) and crude protein content of seven genotypes of sweet potato were investigated. There was considerable genotypic variation in TIA, with a four‐ to fivefold range in roots and a threefold range in stems. The mean TIA in stems at harvest time was 36% of that in roots, whilst the mean TIA in leaves was only 17% of that in roots. The TIA level in roots was correlated with that in stems (r = 0.83, p = 0.02) and leaves (r = 0.70, p = 0.08). In most genotypes the TIA level in vine‐tips was low during the early growth stage, increased from day 30 to day 110 after transplanting, then remained constant in subsequent growth stages. However, in genotype Guang 70‐9, vine‐tips had a high level of TIA at all growth stages. Sweet potato green tissue contained three‐ to fivefold more crude protein than roots. No correlation between TIA and crude protein in sweet potato roots was found across genotypes, but TIA was significantly correlated with crude protein content (r = 0.73, p = 0.06) in sweet potato vine‐tips. Moist heat treatment (MHT) was found to be effective in eliminating TIA in sweet potato. Most TIA in sweet potato green tissue and roots was eliminated by MHT at ≥80 °C, but heat stability was dependent on genotype. Guang 70‐9 had relatively highly heat‐stable trypsin inhibitor. The results suggested that screening for genotypes with high protein content and low TIA and use of an appropriate processing method could improve the utilisation of sweet potato for both human food and animal feed. © 2001 Society of Chemical Industry