Control Development and Modelling for Enhanced Crystal Growth: Application to Novel New Technologies and Extenstion of Conventional Capabilities

用控制增益来描述这些特性可能会产生误导。使用已知效果的前馈来辅助反馈控制的想法是好的，但众所周知。多年来，微观水平的物质目标已经间接地纳入了控制器的设计中。然而，明确地结合热流影响的想法是使用建模来帮助明确地确定控制器的一个很好的例子。尽管自适应控制被认为是反馈控制和前馈控制的一个组成部分，但对自适应控制本身的讨论却很少。我对图表的解释有几点意见。图11中的文字表明，直径的振荡表明需要自适应控制。然而，如果不知道决定拉力和加热器功率的测量值以及系统动力学，则显然不需要自适应控制。当然，图11本身是不够的。图19显示了小孔直径的振荡，这是非最小相位行为的一个指示。然而，接近图形末端的异常似乎是由于非线性效应（或时间变化）。如果异常行为并不罕见，那么这张图将为使用自适应控制提供一个很好的论据。CZ和EMCZ的建模似乎是合适的。验证模型的实验是合理的，我希望可以在可用的拉杆上进行实验。总之，我认为所提议的工作的主要贡献将是开发CZ和EMCZ过程的模型。对控制理论没有新的贡献（提案也没有提出任何要求）。虽然提案指出将开发这些过程的控制器，但对控制问题的分析很薄弱。

Characterizing these in terms of the control gain can be misleading. The idea of using feedforward of known effects to assist the feedback control is good, but well known. Micro-level material objectives have been indirectly incorporated in the design of controllers for years. However, the idea of explicitly incorporating the effects of heat flow is a good example of the use of modeling to help determine the controller explicitly. Although adaptive control is proposed as an integral part of both the feedback control and the feedforward control, very little is said about adaptive control per se.I have a few comments on the interpretations of the graphs. The text in Figure 11 states that the oscillation in diameter indicates the need for adaptive control. However, without knowing the measurements that determine both the pull rate and the heater power, and the system dynamics, it is not apparent that adaptive control is required. Certainly, Figure 11 by itself is insufficient. Figure 19 shows oscillations of the boule diameter, which is one indication of nonminimum phase behavior. However, the anomaly near the end of the graph appears to be due to a nonlinear effect (or a time variation). This graph, if the anomalous behavior is not uncommon, would present a good argument for the use of adaptive control.The modeling of the CZ and EMCZ appears to be appropriate. Experimentation to validate the models is reasonable, and I expect that it can be conducted on the available puller.In summary, I think the primary contribution of the proposed effort will be the development of models for the CZ and EMCZ processes. There will be no new contribution to control theory (and the proposal doesn't claim any). Although the proposal states that controllers for these processes will be developed, the analysis of the control issues is weak.