Regular flow line models for semiconductor cluster tools: A case of lot dependent process times

Author(s):  
James R. Morrison
2019 ◽  
Vol 42 ◽  
Author(s):  
Mark Alfano

Abstract Reasoning is the iterative, path-dependent process of asking questions and answering them. Moral reasoning is a species of such reasoning, so it is a matter of asking and answering moral questions, which requires both creativity and curiosity. As such, interventions and practices that help people ask more and better moral questions promise to improve moral reasoning.


1966 ◽  
Vol 51 (2) ◽  
pp. 224-230 ◽  
Author(s):  
John A. Thomas ◽  
Edward T. Knych

ABSTRACT Norethynodrel antagonized the fructose stimulating effects of exogenous testosterone in sex accessory organs of castrate mice. It was antiandrogenic at both low doses (50 μg) and high doses (400 μg) of testosterone. Norethindrone and ethisterone suppressed fructose formation in the testosterone-treated castrate mouse, but not as effectively as norethynodrel. Norethandrolone exerted no antagonistic activity.


2009 ◽  
Vol 14 (02) ◽  
Author(s):  
D. de la Fuente ◽  
M.J. Pardo
Keyword(s):  

Mathematics ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1029
Author(s):  
Ying-Mei Tu

Since last decade, the cluster tool has been mainstream in modern semiconductor manufacturing factories. In general, the cluster tool occupies 60% to 70% of production machines for advanced technology factories. The most characteristic feature of this kind of equipment is to integrate the relevant processes into one single machine to reduce wafer transportation time and prevent wafer contaminations as well. Nevertheless, cluster tools also increase the difficulty of production planning significantly, particularly for shop floor control due to complicated machine configurations. The main objective of this study is to propose a short-term scheduling model. The noteworthy goal of scheduling is to maximize the throughput within time constraints. There are two modules included in this scheduling model—arrival time estimation and short-term scheduling. The concept of the dynamic cycle time of the product’s step is applied to estimate the arrival time of the work in process (WIP) in front of machine. Furthermore, in order to avoid violating the time constraint of the WIP, an algorithm to calculate the latest time of the WIP to process on the machine is developed. Based on the latest process time of the WIP and the combination efficiency table, the production schedule of the cluster tools can be re-arranged to fulfill the production goal. The scheduling process will be renewed every three hours to make sure of the effectiveness and good performance of the schedule.


Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 456
Author(s):  
Dongsheng Qian ◽  
Chengfei Ma ◽  
Feng Wang

Hot rolling is an essential process for the shape-forming of bearing steel. It plays a significant role in the formation and distribution of flow lines. In this work, the effect of flow lines is investigated by analyzing the microstructure and mechanical anisotropy of hot-rolled bearing steel. It was found that carbides rich with Cr and Mn elements are distributed unevenly along the flow-line direction of the hot-rolled bearing steel. Moreover, the mechanical characterization indicates that ultimate tensile strength and yield strength do not have any significant difference in two directions. Nevertheless, an ultrahigh section shrinkage of 57.51% is obtained in the 0° sample that has parallel flow lines, while 90° sample shows poor section shrinkage. The uneven distributed carbides will affect the direction and speed of crack propagation during tensile deformation. Therefore, the 0° and 90° samples exhibit great difference in plastic property. Meanwhile, after tensile deformation, a delaminated texture is observed in the flow lines, which may be caused by different degrees of deformation of grains due to the uneven distribution of carbides. The results of this work may provide guidance for controlling and optimizing flow lines in the manufacturing of bearing rings.


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