Simulation Time Versus Real Time in Computer Simulation of Vapor Deposition

1970 ◽  
Vol 41 (13) ◽  
pp. 5348-5350 ◽  
Author(s):  
George M. White ◽  
Farid F. Abraham
Keyword(s):  
Computer Simulation ◽  
Real Time ◽  
Vapor Deposition ◽  
Simulation Time

A Unitary-UCA-Root-MUSIC Algorithm Based on MSWF

2014 ◽  
Vol 610 ◽  
pp. 339-344
Author(s):  
Qiang Guo ◽  
Yun Fei An
Keyword(s):  
Computer Simulation ◽  
Computational Complexity ◽  
Real Time ◽  
Unitary Transformation ◽  
Wiener Filter ◽  
Doa Estimation ◽  
Signal Subspace ◽  
Music Algorithm ◽  
Multi Stage ◽  
Simulation Results

A UCA-Root-MUSIC algorithm for direction-of-arrival (DOA) estimation is proposed in this paper which is based on UCA-RB-MUSIC [1]. The method utilizes not only a unitary transformation matrix different from UCA-RB-MUSIC but also the multi-stage Wiener filter (MSWF) to estimate the signal subspace and the number of sources, so that the new method has lower computational complexity and is more conducive to the real-time implementation. The computer simulation results demonstrate the improvement with the proposed method.

scholarly journals Real-time in-situ Investigation of III-V Nanowire Growth using Custom-designed Hybrid Chemical Vapor Deposition-TEM

2017 ◽  
Vol 23 (S1) ◽  
pp. 1716-1717 ◽  
Author(s):  
Kimberly Dick Thelander ◽  
L. Reine Wallenberg ◽  
Axel R. Persson ◽  
Marcus Tornberg ◽  
Daniel Jacobsson ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Real Time ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Nanowire Growth ◽  
In Situ Investigation

Real-Time Diagnosis of Nano-Sized Contaminant Particles Generated in TiN Metal Organic Chemical Vapor Deposition

2009 ◽  
Vol 2 ◽  
pp. 035501 ◽  
Author(s):  
Jeonggil Na ◽  
Taesung Kim ◽  
Jae-Boong Choi ◽  
Ju-Young Yun ◽  
Yong-Hyeon Shin ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Real Time ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Organic Chemical ◽  
Metal Organic ◽  
Tin Metal ◽  
Organic Chemical Vapor Deposition ◽  
Time Diagnosis

Real-Time Composition And Thickness Control Techniques In A Metalorganic Chemical Vapor Deposition Process

1995 ◽  
Vol 406 ◽  
Author(s):  
M. S. Gaffneyt ◽  
C. M. Reavesl ◽  
A. L Holmes ◽  
R. S. Smith ◽  
S. P. DenBaars
Keyword(s):  
Chemical Vapor Deposition ◽  
Real Time ◽  
Vapor Deposition ◽  
Metalorganic Chemical Vapor Deposition ◽  
Chemical Vapor ◽  
Normal Operation ◽  
Growth Monitoring ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metalorganic Chemical

AbstractMetalorganic chemical vapor deposition (MOCVD) is a process used to manufacture electronic and optoelectronic devices that has traditionally lacked real-time growth monitoring and control. We have developed control strategies that incorporate monitors as real-time control sensors to improve MOCVD growth. An analog control system with an ultrasonic concentration monitor was used to reject bubbler concentration disturbances which exist under normal operation, during the growth of a four-period GaInAs/InP superlattice. Using X-ray diffraction, it was determined that the normally occurring concentration variations led to a wider GaInAs peak in the uncompensated growths as compared to the compensated growths, indicating that closed loop control improved GaInAs composition regulation. In further analysis of the X-ray diffraction curves, superlattice peaks were used as a measure of high crystalline quality. The compensated curve clearly displayed eight orders of satellite peaks, whereas the uncompensated curve shows little evidence of satellite peaks.

Intelligent Process Control of Silicon Nitride Chemical Vapor Deposition

1994 ◽  
Vol 363 ◽  
Author(s):  
Paul S. Bowen ◽  
Steve K. Phelps ◽  
Harry I. Ringermacher ◽  
Richard D. Veltri
Keyword(s):  
Chemical Vapor Deposition ◽  
High Temperature ◽  
Silicon Nitride ◽  
Process Control ◽  
Real Time ◽  
Vapor Deposition ◽  
Process Model ◽  
Chemical Vapor ◽  
Laser Ultrasonics ◽  
Hierarchical Architecture

AbstractThe chemical vapor deposition of silicon nitride can be used to protect advanced materials and composites from high temperature, corrosive, and oxidative environments. Desired coating characteristics, such as uniformity and morphology, cannot be measured in-situ by traditional sensors due to the adverse conditions within the high-temperature reactor. A control strategy has been developed which utilizes a process model and an advanced laser-based sensor to measure the deposition rate of the silicon nitride coating in real-time. The control system is based on a three level hierarchical architecture which functionally separates the process control into PID, supervisory and advanced sensor-based control. Optimal setpoint schedules for the supervisory level are derived from a quasi-fuzzy logic inverse mapping of the process model. An advanced sensor utilizing laser ultrasonics provides real-time coating thickness estimates. Model bias is characterized for each reactor and is correlated on-line with the sensor's deposit thickness estimate. Deviations from model predictions may result in parametric changes to the process model. New setpoint schedules are then created as input to the supervisory control level by regenerating the inverse map of the updated process model.

Real-time engine model development based on time complexity analysis

2021 ◽  
pp. 146808742110397
Author(s):  
Haotian Chen ◽  
Kun Zhang ◽  
Kangyao Deng ◽  
Yi Cui
Keyword(s):  
Real Time ◽  
Time Complexity ◽  
Complexity Analysis ◽  
High Accuracy ◽  
The Real ◽  
Cycle Simulation ◽  
Crank Angle ◽  
Time Requirements ◽  
Improved Model ◽  
Simulation Time

Real-time simulation models play an important role in the development of engine control systems. The mean value model (MVM) meets real-time requirements but has limited accuracy. By contrast, a crank-angle resolved model, such as the filling -and-empty model, can be used to simulate engine performance with high accuracy but cannot meet real-time requirements. Time complexity analysis is used to develop a real-time crank-angle resolved model with high accuracy in this study. A method used in computer science, program static analysis, is used to theoretically determine the computational time for a multicylinder engine filling-and-empty (crank-angle resolved) model. Then, a prediction formula for the engine cycle simulation time is obtained and verified by a program run test. The influence of the time step, program structure, algorithm and hardware on the cycle simulation time are analyzed systematically. The multicylinder phase shift method and a fast calculation method for the turbocharger characteristics are used to improve the crank-angle resolved filling-and-empty model to meet real-time requirements. The improved model meets the real-time requirement, and the real-time factor is improved by 3.04 times. A performance simulation for a high-power medium-speed diesel engine shows that the improved model has a max error of 5.76% and a real-time factor of 3.93, which meets the requirement for a hardware-in-the-loop (HIL) simulation during control system development.

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