Micro Pattern Filling Simulation to See the Effects of Process Parametric Variables on Imprinting

2007 ◽  
Author(s):  
Jinho Mok ◽  
Sukwon Lee ◽  
JeHyoung Ryu ◽  
Hyuk Kim ◽  
Sin Kwon ◽  
...  
Keyword(s):  
Process Parameters ◽  
Quantitative Data ◽  
New Technology ◽  
Process Conditions ◽  
Whole Process ◽  
Free Process ◽  
Micro Pattern ◽  
Minimum Number ◽  
Set Up ◽  
Nano Imprint

The nano imprint lithography, a new approach to lithography, is a very useful alternative for the conventional photolithography process. To apply this new technology to the lithography process, new equipment, process parameters and post processes must be taken into consideration. If the defects during imprinting can be detected by optical measuring only after finishing the whole process, the engineers have no choice but analyze the sample of a final form to analogize the cause of defects. To set up the optimal process conditions, simulation is a very useful method in terms of not only the minimum number of trial and error but also the quantitative data based design. In this study, a few process parameters that affect the micro pattern forming in the nano imprint process are chosen and examined to present the quantitative data useful to set up the process conditions for the residual bubble free process.

scholarly journals Dynamic modeling of the isoamyl acetate reactive distillation process

2017 ◽  
Vol 19 (1) ◽  
pp. 59-66 ◽  
Author(s):  
Syed Sadiq Ali ◽  
Sk Safdar Hossain ◽  
Mohammad Asif
Keyword(s):  
Dynamic Modeling ◽  
Process Parameters ◽  
Reactive Distillation ◽  
Scale Up ◽  
Isoamyl Acetate ◽  
Industrial Applications ◽  
Process Conditions ◽  
Whole Process ◽  
Product Flow ◽  
The Stability

Abstract The cost-effectiveness of reactive distillation (RD) processes makes them highly attractive for industrial applications. However, their preliminary design and subsequent scale-up and operation are challenging. Specifically, the response of RD system during fluctuations in process parameters is of paramount importance to ensure the stability of the whole process. As a result of carrying out simulations using Aspen Plus, it is shown that the RD process for isoamyl acetate production was much more economical than conventional reactor distillation configuration under optimized process conditions due to lower utilities consumption, higher conversion and smaller sizes of condenser and reboiler. Rigorous dynamic modeling of RD system was performed to evaluate its sensitivity to disturbances in critical process parameters; the product flow was quite sensitive to disturbances. Even more sensitive was product composition when the disturbance in heat duties of condenser or reboiler led to a temperature decrease. However, positive disturbance in alcohol feed is of particular concern, which clearly made the system unstable.

Orthogonal Study on the Degradation of Aniline Process Parameters by Ultrasonic

2014 ◽  
Vol 488-489 ◽  
pp. 70-73
Author(s):  
Yong Guang Bi ◽  
Min Xia Huang
Keyword(s):  
Process Parameters ◽  
Ph Value ◽  
New Technology ◽  
Optimum Process ◽  
Process Conditions ◽  
Ultrasonic Power ◽  
Solution Ph ◽  
Ultrasonic Time ◽  
Ultrasonic Degradation ◽  
The Impact

Objective: To optimize the ultrasonic degradation of aniline wastewater process parameters. Methods: ultrasonic power, ultrasonic time, ultrasonic temperature, pH value, etc. 4 orthogonal factors and determine the optimum process conditions. Results: In the ultrasonic power 320W, ultrasonic time was 60min, ultrasonic temperature is 30 °C, pH value of 4 under the action of ultrasound sonication best, under optimum conditions, aniline degradation rate of 90.08%, and the various factors the impact of the size order of ultrasonic temperature> ultrasonic time> ultrasonic power> solution pH. Conclusion: Ultrasonic degradation of organic matter, is easy to operate, efficient, non-polluting or less polluting characteristics, is a better degradation of aniline wastewater new technology.

scholarly journals Chitosan Micro-Grooved Membranes with Increased Asymmetry for the Improvement of the Schwann Cell Response in Nerve Regeneration

2021 ◽  
Vol 22 (15) ◽  
pp. 7901
Author(s):  
Luca Scaccini ◽  
Roberta Mezzena ◽  
Alessia De Masi ◽  
Mariacristina Gagliardi ◽  
Giovanna Gambarotta ◽  
...  
Keyword(s):  
Schwann Cell ◽  
Nerve Regeneration ◽  
High Fidelity ◽  
Solvent Casting ◽  
Peripheral Nerve Injuries ◽  
Cell Shaping ◽  
Micro Pattern ◽  
Chitosan Scaffolds ◽  
Set Up ◽  
Different Levels

Peripheral nerve injuries are a common condition in which a nerve is damaged, affecting more than one million people every year. There are still no efficient therapeutic treatments for these injuries. Artificial scaffolds can offer new opportunities for nerve regeneration applications; in this framework, chitosan is emerging as a promising biomaterial. Here, we set up a simple and effective method for the production of micro-structured chitosan films by solvent casting, with high fidelity in the micro-pattern reproducibility. Three types of chitosan directional micro-grooved patterns, presenting different levels of symmetricity, were developed for application in nerve regenerative medicine: gratings (GR), isosceles triangles (ISO) and scalene triangles (SCA). The directional patterns were tested with a Schwann cell line. The most asymmetric topography (SCA), although it polarized the cell shaping less efficiently, promoted higher cell proliferation and a faster cell migration, both individually and collectively, with a higher directional persistence of motion. Overall, the use of micro-structured asymmetrical directional topographies may be exploited to enhance the nerve regeneration process mediated by chitosan scaffolds.

Settings, Experimentation and Evaluation of the Simulation Models

2013 ◽  
Vol 309 ◽  
pp. 366-371 ◽  
Author(s):  
František Manlig ◽  
Radek Havlik ◽  
Alena Gottwaldova
Keyword(s):  
Simulation Model ◽  
New Technology ◽  
Simulation Models ◽  
Manufacturing Processes ◽  
Customer Requirements ◽  
Evaluation Functions ◽  
Operational Management ◽  
Minimum Number ◽  
User Friendly ◽  
Setting Parameters

This paper deals with research in computer simulation of manufacturing processes. The paper summarizes the procedures associated with developing the model, experimenting with and evaluating the model results. The key area is of experimentation with the simulation model and evaluation using indicators or multi-criteria functions. With regards to the experiment the crucial variables are the simulation model. The key ideas are to set the number of variables, depending on what a given simulation will be. For example, when introducing new technology into production, modify the type of warehouse, saving workers, thus economizing. The simulation models for the operational management uses simplified models, if possible, a minimum number of variables to obtain the result in shortest possible time. These models are more user friendly and the course will be conducted mostly in the background. An example of a criteria function is the number of parts produced or production time. Multi-criteria function has given us the opportunity to make better quality decisions. It is based on the composition of several parameters, including their weight to one end point. The type of evaluation functions, whether it is an indicator or criteria function is selected and based on customer requirements. In most cases it is recommended to use the multi-dimensional function. It gives us a more comprehensive view of the results from the model and facilitates decision-making. The result of this paper is a display of setting parameters for the experimentation on a sample model. Furthermore, the comparisons of results with a multi-criteria objective function and one-criterion indicator.

Heat Transfer and Crystallization Modeling during Compression Molding of Thermoplastic Composite Parts

2015 ◽  
Vol 651-653 ◽  
pp. 1507-1512 ◽  
Author(s):  
Jalal Faraj ◽  
Baptiste Pignon ◽  
Jean Luc Bailleul ◽  
Nicolas Boyard ◽  
Didier Delaunay ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Physical Properties ◽  
Volume Fraction ◽  
Thermoplastic Composite ◽  
Large Temperature ◽  
Process Conditions ◽  
Thermoplastic Resin ◽  
Whole Process ◽  
Low Viscosity ◽  
Thermo Physical Properties

We present in this paper, the coupling of heat transfer to the crystallization of composite in a closed mold. The composite is based on thermoplastic resin (low viscosity PA 66) with glass fiber (50% volume fraction). In order to realize this coupling, an accurate characterizationof thermo physical properties in process conditions, especially in the molten and solid state is needed. In addition, theidentification of the parameters of crystallization kinetics is required. Therefore, we present the methods that were used to study the thermo physical properties as the thermal conductivity, heat capacity and the specific volume. Moreover, the kinetic of crystallization was estimated over a large temperature range by using Flash DSC and classical DSC. In order to validate the measurements, the whole process was modeled by finite elements. The model includes the resolution of the strong coupling between the heat transfer and crystallization. Finally, the experimental and numerical results were compared.

A Hybrid Approach to Computer-Aided Process Planning for Prismatic Parts

1994 ◽  
Author(s):  
Y. F. Zhang ◽  
A. Y. C. Nee ◽  
J. Y. H. Fuh
Keyword(s):  
Process Planning ◽  
Hybrid Approach ◽  
Optimization Method ◽  
Optimal Operation ◽  
Operation Sequencing ◽  
Computer Aided Process Planning ◽  
Prismatic Parts ◽  
Minimum Number ◽  
Set Up

Abstract One of the most difficult tasks in automated process planning is the determination of operation sequencing. This paper describes a hybrid approach for identifying the optimal operation sequence of machining prismatic parts on a three-axis milling machining centre. In the proposed methodology, the operation sequencing is carried out in two levels of planning: set-up planning and operation planning. Various constraints on the precedence relationships between features are identified and rules and heuristics are created. Based on the precedence relationships between features, an optimization method is developed to find the optimal plan(s) with minimum number of set-ups in which the conflict between the feature precedence relationships and set-up sequence is avoided. For each set-up, an optimal feature machining sequence with minimum number of tool changes is also determined using a developed algorithm. The proposed system is still under development and the hybrid approach is partially implemented. An example is provided to demonstrate this approach.

Prediction model for the mechanical properties of compacted poplar powder generated via hot-pressing

BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 4947-4962
Author(s):  
Jin Yan ◽  
Jianan Liu ◽  
Liqiang Zhang ◽  
Zhili Tan ◽  
Haoran Zhang ◽  
...  
Keyword(s):  
Neural Network ◽  
Mechanical Properties ◽  
Network Model ◽  
Process Parameters ◽  
Neural Network Model ◽  
Hot Pressing ◽  
Process Conditions ◽  
Wood Powder ◽  
Single Factor ◽  
The Relationship

The influence of the process parameters on the mechanical properties of compact wood powder generated via hot-pressing was analyzed through a single-factor experiment. The mechanical properties exhibited a nonlinear trend relative to the process conditions of hot-pressed compact wood powder. The relationship models between the process parameters and the mechanical properties for the compact wood powder were established by applying a multiple regression analysis and neural network methods combined with data from an orthogonal array design. A comparison between experimental and predicted results was made to investigate the accuracy of the established models by applying several data groups among the single-factor experiments. The results showed that the accuracy of the neural network model in terms of predicting the mechanical properties was greater compared with the multiple regression model. This demonstrates that the established neural network model had a better prediction performance, and it can accurately map the relationship between the process conditions and the mechanical properties of the compact wood powder.

Model Approach for Displaying Dynamic Filament Displacement during Impregnation of Continuous Fibres Based on the Theory of Similarity – Theory and Modelling

2021 ◽  
Vol 36 (4) ◽  
pp. 423-434
Author(s):  
F. Schulte-Hubbert ◽  
D. Drummer ◽  
L. Hoffmann
Keyword(s):  
Process Parameters ◽  
Similarity Theory ◽  
Dynamic Compaction ◽  
Experimental Investigations ◽  
Process Conditions ◽  
Scaled Model ◽  
Compaction Behavior ◽  
Thermoplastic Matrix ◽  
Analytical Foundation ◽  
Reinforced Thermoplastics

Abstract The underlying process for the production of textile reinforced thermoplastics is the impregnation of dry textile reinforcements with a thermoplastic matrix. The process parameters such as temperature, time and pressure of the impregnation are mainly determined by the permeability of the reinforcement. This results from a complex interaction of hydrodynamic compaction and relaxation behavior caused by textile and process parameters. The foundation for the description and optimization of impregnation progresses is therefore the determination of the pressure-dependent permeability of fibre textiles. Previous experimental investigations have shown that the dynamic compaction behavior during the impregnation of fibre reinforcements with thermoplastics or thermosets can be successfully characterized. However, for most cases, an analytical representation has not been possible due to the complexity of the process. Although it may be possible to reproduce this behavior by numerical calculations, the results need to be confirmed by experiments. This paper lays the analytical foundation for building a scaled model system, based on the theory of similarity, to observe, measure, and evaluate the dynamic compaction behavior of textile reinforcements under controlled process conditions.

scholarly journals Compliant control for wearable exoskeleton robot based on human inverse kinematics

2018 ◽  
Vol 15 (6) ◽  
pp. 172988141881213 ◽  
Author(s):  
Brahim Brahmi ◽  
Maarouf Saad ◽  
Abdelkrim Brahmi ◽  
Cristobal Ochoa Luna ◽  
Mohammad Habibur Rahman
Keyword(s):  
Inverse Kinematics ◽  
Sliding Mode ◽  
New Technology ◽  
Time Delay Estimation ◽  
Compliance Control ◽  
Exoskeleton Robot ◽  
Main Challenge ◽  
Compliant Control ◽  
Wearable Exoskeleton ◽  
Set Up

Rehabilitation robots are a new technology dedicated to the physiotherapy and assistance motion and has aroused great interest in the scientific community. These kinds of robots have shown a high potential in limiting the patient’s disability, increasing its functional movements and helping him/her in daily living activities. This technology is still an emerging area and suffers from many challenges like compliance control and human–robot collaboration. The main challenge addressed in this research is to ensure that the exoskeleton robot provides an appropriate compliance control that allows it to interact perfectly with humans. This article investigates a new compliant control based on a second-order sliding mode with adaptive-gain incorporating time delay estimation. The control uses human inverse kinematics to complete active rehabilitation protocols for an exoskeleton robot with unknown dynamics and unforeseen disturbances. The stability analysis is formulated and demonstrated based on Lyapunov function. An experimental physiotherapy session with three healthy subjects was set up to test the effectiveness of the proposed control, using virtual reality environment.

Real-time observation of cathodic cleaning during variable-polarity gas tungsten arc welding of aluminium alloy

2009 ◽  
Vol 223 (9) ◽  
pp. 1143-1157 ◽  
Author(s):  
R Sarrafi ◽  
D Lin ◽  
R Kovacevic
Keyword(s):  
Real Time ◽  
Process Parameters ◽  
Arc Welding ◽  
Molten Pool ◽  
Gas Tungsten Arc Welding ◽  
Process Conditions ◽  
Current Electrode ◽  
Gas Tungsten Arc ◽  
Variable Polarity ◽  
Gas Tungsten

Online observation is expected to provide a better understanding of the cathodic cleaning of oxides from the molten pool during variable-polarity gas tungsten arc welding (VP GTAW) of aluminium alloys. In this paper, a machine-vision system with appropriate illumination and filtering is used to monitor in real time the effect of different process parameters on the cleaning of oxides from the molten pool during VP GTAW of Al 6061. Based on the observations, the process conditions under which a clean molten pool can be achieved are determined. In addition, the control of the welding process to maintain the consistency of cathodic cleaning is discussed. The results showed that in order to have an oxide-free molten pool, the solid surface in front of the molten pool should be cleaned from oxides by the electric arc. The choice of process parameters to satisfy this condition has been discussed. It was found that the percentage of direct current electrode positive (DCEP) polarity in the cycle of current has the highest impact on the cathodic cleaning, with the arc current having less influence, and the welding speed showing the least effect. Furthermore, in order to keep the consistency of oxide cleaning, process parameters should be set or controlled to maintain the cleaned zone larger than the molten pool.

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