process planning, as a critical stage integrating the design and manufacturing phase in a manufacturing environment, has been automated to meet the needs for higher productivity and lower production cost. Being an inp...
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process planning, as a critical stage integrating the design and manufacturing phase in a manufacturing environment, has been automated to meet the needs for higher productivity and lower production cost. Being an input to various systems such as scheduling and routing, process planning results are of great importance in the manufacturing stage. Though feature extraction and sequence optimization have been given much attention, the processparameters are rarely dealt with. This paper focuses on the development of a new generative computer aided process planning (CAPP) framework for rotational components. The developed framework includes modules for feature extraction based on CAD application programming interfaces, determination of the optimum sequence and generation of optimum processparameters. The optimization of the machining operations is achieved using the evolutionary technique. The approach resulted in the reduction and prediction of machining time and cost. The framework is demonstrated with a case study.
The optimization of processparameters and catalyst compositions for the CO2 oxidative coupling of methane (CO2-OCM) reaction over CaO-MnO/CeO2 catalyst was developed using Response Surface Methodology (RSM). The rela...
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The optimization of processparameters and catalyst compositions for the CO2 oxidative coupling of methane (CO2-OCM) reaction over CaO-MnO/CeO2 catalyst was developed using Response Surface Methodology (RSM). The relationship between the responses, i.e. CH4 conversion, C hydrocarbons selectivity or yield, with four independent variables, i.e. CO2/CH4 ratio, reactor temperature, wt.% CaO and wt.% MnO in the catalyst, were presented as empirical mathematical models. The maximum C hydrocarbons selectivity and yields of 82.62% and 3.93%, respectively, were achieved by the individual-response optimization at the corresponding optimal processparameters and catalyst compositions. However, the CH4 conversion was a saddle function and did not show a unique optimum as revealed by the canonical analysis. Moreover pertaining to simultaneous multi-responses optimization, the maximum C selectivity and yield of 76.56% and 3.74%, respectively, were obtained at a unique optimal processparameters and catalyst compositions. It may be deduced that both individual- and multi-responses optimizations are useful for the recommendation of optimal processparameters and catalyst compositions for the CO2-OCM process. (c) 2005 Elsevier B.V. All rights reserved.
In this thesis, a series of typical planar gas-assisted injection molding parts are created. With the help of CAE software moldflow, the GAIM process of these parts are simulated and the analysis results are received....
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In this thesis, a series of typical planar gas-assisted injection molding parts are created. With the help of CAE software moldflow, the GAIM process of these parts are simulated and the analysis results are received. By the thorough study and mathematic treatment of the results, a set of rules between gas parameters and gas penetration length are concluded, furthermore, three formulas of gas parameters and gas penetration length are deduced. At the end, three verifying models are created to validate the formulas.
In IC and MEMS ( Micro Electric Mechanical Systems) packaging processing, success applications of plasma cleaning technology depends on cleaning processparameters such as pressure, RF power, cleaning time and cleanin...
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ISBN:
(纸本)0780383613
In IC and MEMS ( Micro Electric Mechanical Systems) packaging processing, success applications of plasma cleaning technology depends on cleaning processparameters such as pressure, RF power, cleaning time and cleaning gas etc.. The affects of cleaning parameters to strength of wire bonding are investigated in the paper. We select a sort of hybrids PCBs to do cleaning experiment in difference processparameters, and then do wire bonding and pull tests. The experimental results demonstrate: (1) The cleaning effect is very good when RF power is around 200similar to600W, and typical PF power value is 600W. (2) In the condition of between 400-600W RF power, cleaned about 10-15minutes can get a good cleaning effect. (3) The cleaning effect is better when the samples were placed in ground electrode than in anode. (4) When the gas pressure is in 100similar to120 mT or in 140similar to180 mT, can obtain better cleaning effect. (5) The smaller distance and symmetrical electrode structures have better cleaning effect.
In this study, a systematic approach to achieve a globally optimal Chemical Mechanical Polishing ( CMP) process is carried out. In this new approach, the orthogonal array technique adopted from the Taguchi method is u...
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In this study, a systematic approach to achieve a globally optimal Chemical Mechanical Polishing ( CMP) process is carried out. In this new approach, the orthogonal array technique adopted from the Taguchi method is used to realize an efficiently experimental design. The RBFNF neural fuzzy network is then applied to model the complex CMP process. The signal-to noise ratio (S/N) analysis (ANOVA) technique used in the conventional Taguchi method is also implemented to obtain the local optimum processparameters. The globally of optimal parameters are successively acquired in terms of the trained RBFNF network. In order to increase CMP throughput, a two-stage optimal strategy is also proposed. Experimental results demonstrate that the two-stage strategy performs better than the original approach even though the total processing time is reduced by 1/6.
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