Using control and repairing loops to remove production errors is not the only solution to increase the manufacturing yield. The production of errors can also be directly avoided, prevented or eliminated, even as early...Using control and repairing loops to remove production errors is not the only solution to increase the manufacturing yield. The production of errors can also be directly avoided, prevented or eliminated, even as early as in the planning phase. This paper suggests that the idea of Process Signatures can help to achieve Loopless Production. Loopless Production offers an option to guarantee the production quality towards the vision of the zero-defect manufacturing. It is considered that closed loops are used in a production process chain to identify and to correct the unknown and the systematic errors. These errors can actually be avoided through specifically adjusted or optimal arranged production processes. This puts a higher demand on the understanding of processes, which involve various energy-material interactions. This demand can be met via Process Signatures which aims to develop a process-independent description method of effects of processes. A supportive relationship is foreseen between Process Signatures and Loopless Production. The combination of these two ideas shall allow the simplification of the work for the rationalization of process sequences, the streamlining of closed loops as well as the selection of optimal substitute processes.展开更多
Crystal morphology is known to be of great importance to the end-use properties of crystal products, and to affect down-stream processing such as filtration and drying. However, it has been previously regarded as too ...Crystal morphology is known to be of great importance to the end-use properties of crystal products, and to affect down-stream processing such as filtration and drying. However, it has been previously regarded as too challenging to achieve automatic closed-loop control. Previous work has focused on controlling the crystal size distribution, where the size of a crystal is often defined as the diameter of a sphere that has the same volume as the crystal. This paper reviews the new advances in morphological population balance models for modelling and simulating the crystal shape distribution （CShD）, measuring and estimating crystal facet growth kinetics, and two- and three-dimensional imaging for on-line characterisation of the crystal morphology and CShD. A framework is presented that integrates the various components to achieve the ultimate objective of model-based closed-loop control of the CShD. The knowledge gaps and challenges that require further research are also identified.展开更多
文摘Using control and repairing loops to remove production errors is not the only solution to increase the manufacturing yield. The production of errors can also be directly avoided, prevented or eliminated, even as early as in the planning phase. This paper suggests that the idea of Process Signatures can help to achieve Loopless Production. Loopless Production offers an option to guarantee the production quality towards the vision of the zero-defect manufacturing. It is considered that closed loops are used in a production process chain to identify and to correct the unknown and the systematic errors. These errors can actually be avoided through specifically adjusted or optimal arranged production processes. This puts a higher demand on the understanding of processes, which involve various energy-material interactions. This demand can be met via Process Signatures which aims to develop a process-independent description method of effects of processes. A supportive relationship is foreseen between Process Signatures and Loopless Production. The combination of these two ideas shall allow the simplification of the work for the rationalization of process sequences, the streamlining of closed loops as well as the selection of optimal substitute processes.
基金Financial support from the following projects and organisa- tions are acknowledged： the China One Thousand Talent Scheme, the National Natural Science Foundation of China （NNSFC） under its Major Research Scheme of Meso-scale Mechanism and Control in Multi-phase Reaction Processes （project reference： 91434126）, the Natural Science Foundation of Guangdong Province （project reference： 2014A030313228）, the UK Engineering and Physical Sciences Research Council （EPSRC） for the projects of Shape （EP/C009541） and StereoVision （EP/E045707）, and the Technology Strategy Board （TSB） for the project of High Value Manufacturing CGM （TP/BD059E）.
文摘Crystal morphology is known to be of great importance to the end-use properties of crystal products, and to affect down-stream processing such as filtration and drying. However, it has been previously regarded as too challenging to achieve automatic closed-loop control. Previous work has focused on controlling the crystal size distribution, where the size of a crystal is often defined as the diameter of a sphere that has the same volume as the crystal. This paper reviews the new advances in morphological population balance models for modelling and simulating the crystal shape distribution （CShD）, measuring and estimating crystal facet growth kinetics, and two- and three-dimensional imaging for on-line characterisation of the crystal morphology and CShD. A framework is presented that integrates the various components to achieve the ultimate objective of model-based closed-loop control of the CShD. The knowledge gaps and challenges that require further research are also identified.
