In precision machining of complex curved surface parts with high performance, geometry accuracy is not the only constraint, but the performance should also be met. Performance of this kind of parts is closely related ...In precision machining of complex curved surface parts with high performance, geometry accuracy is not the only constraint, but the performance should also be met. Performance of this kind of parts is closely related to the geometrical and physical parameters, so the final actual size and shape are affected by multiple source constraints, such as geometry, physics, and performance. These parts are rather difficult to be manufactured and new manufacturing method according to performance requirement is urgently needed. Based on performance and manufacturing requirements for complex curved surface parts, a new classification method is proposed, which divided the complex curved surface parts into two categories： surface re-design complex curved surface parts with multi-source constraints（PRCS） and surface unique complex curved surface parts with pure geometric constraints（PUCS）. A correlation model is constructed between the performance and multi-source constraints for PRCS, which reveals the correlation between the performance and multi-source constraints. A re-design method is also developed. Through solving the correlation model of the typical paws performance-associated surface, the mapping relation between the performance-associated surface and the related removal amount is obtained. The explicit correlation model and the method for the corresponding related removal amount of the performance-associated surface are built based on the classification of surface re-design complex curved surface parts with multi-source constraints. Research results have been used in the actual processing of the typical parts such as radome, common bottom components, nozzle, et al., which shows improved efficiency and accuracy of the precision machining for the surface re-design parts with complex curved surface.展开更多
New Normal becomes the way out to keep Indonesia's weakened economy because of covid-19 pandemic stays in balance.Of course,New Normal must be well-balanced with the application of strict protocols to reduce trans...New Normal becomes the way out to keep Indonesia's weakened economy because of covid-19 pandemic stays in balance.Of course,New Normal must be well-balanced with the application of strict protocols to reduce transmission rates and anticipate a surge in new cases.From a few points of pandemic protocols,using face mask is considered as the most-effective basic need.Re-designing the mask is aiming at eliminating the worsening feature and developing the improving feature.This research is developing the widely used 1-ply mask,which doesn't meet WHO standard regarding cloth-material mask that must be made in 3-ply.The method used in this research is TRIZ(Teoriya Resheniya Izobreatatelskikh Zadatch),an inventive problem solving theory to the issues regarding ideas,products,or concepts,in this case is face mask redesigning concept.In this research,the data are collected by doing library research to obtain secondary data that will be processed in qualitative and quantitative methods.The results show the aspects that should be eliminated from cloth-material face mask are brittle for being easily damaged,short period of usage,and non-reusable.After the redesigning concept is carried out using the principles and features of TRIZ method,some aspects such as weight,material,design,and functionality are developed.The result is a relatively light weight face mask because the using of PLA+filament-based material with good durability and environmentally friendly.This design has a longer period of usage,and the user only needs to replace the additional inserted tissue every 4 hours.The researchers hope that the new design can be further developed by government to deal with New Normal and other possibilities in the future.展开更多
基金supported by Key Program of National Natural Science Foundation of China(Grant No.50835001)Program for New Century Excellent Talents in University,China(Grant No.NCET-13-0081)
文摘In precision machining of complex curved surface parts with high performance, geometry accuracy is not the only constraint, but the performance should also be met. Performance of this kind of parts is closely related to the geometrical and physical parameters, so the final actual size and shape are affected by multiple source constraints, such as geometry, physics, and performance. These parts are rather difficult to be manufactured and new manufacturing method according to performance requirement is urgently needed. Based on performance and manufacturing requirements for complex curved surface parts, a new classification method is proposed, which divided the complex curved surface parts into two categories： surface re-design complex curved surface parts with multi-source constraints（PRCS） and surface unique complex curved surface parts with pure geometric constraints（PUCS）. A correlation model is constructed between the performance and multi-source constraints for PRCS, which reveals the correlation between the performance and multi-source constraints. A re-design method is also developed. Through solving the correlation model of the typical paws performance-associated surface, the mapping relation between the performance-associated surface and the related removal amount is obtained. The explicit correlation model and the method for the corresponding related removal amount of the performance-associated surface are built based on the classification of surface re-design complex curved surface parts with multi-source constraints. Research results have been used in the actual processing of the typical parts such as radome, common bottom components, nozzle, et al., which shows improved efficiency and accuracy of the precision machining for the surface re-design parts with complex curved surface.
文摘New Normal becomes the way out to keep Indonesia's weakened economy because of covid-19 pandemic stays in balance.Of course,New Normal must be well-balanced with the application of strict protocols to reduce transmission rates and anticipate a surge in new cases.From a few points of pandemic protocols,using face mask is considered as the most-effective basic need.Re-designing the mask is aiming at eliminating the worsening feature and developing the improving feature.This research is developing the widely used 1-ply mask,which doesn't meet WHO standard regarding cloth-material mask that must be made in 3-ply.The method used in this research is TRIZ(Teoriya Resheniya Izobreatatelskikh Zadatch),an inventive problem solving theory to the issues regarding ideas,products,or concepts,in this case is face mask redesigning concept.In this research,the data are collected by doing library research to obtain secondary data that will be processed in qualitative and quantitative methods.The results show the aspects that should be eliminated from cloth-material face mask are brittle for being easily damaged,short period of usage,and non-reusable.After the redesigning concept is carried out using the principles and features of TRIZ method,some aspects such as weight,material,design,and functionality are developed.The result is a relatively light weight face mask because the using of PLA+filament-based material with good durability and environmentally friendly.This design has a longer period of usage,and the user only needs to replace the additional inserted tissue every 4 hours.The researchers hope that the new design can be further developed by government to deal with New Normal and other possibilities in the future.
