Dear Editor,In the absence of vaccine,the mounting second wave of COVID-19 infections worldwide calls for the rapid development of human neutralizing antibodies to prevent and treat COVID-19(Lee et al.2020).Considerin...Dear Editor,In the absence of vaccine,the mounting second wave of COVID-19 infections worldwide calls for the rapid development of human neutralizing antibodies to prevent and treat COVID-19(Lee et al.2020).Considering the high cost and long development cycle of human neutralizing antibodies,we turned to anti-SARS-Co V-2 Ig Y for cheap and fast scale up.展开更多
Blisks with the integral structure are key parts used in new jet engines to promote the performance of aircrafts,which also increases the complexity of tool orientation planning in the five-axis machining.It is an ess...Blisks with the integral structure are key parts used in new jet engines to promote the performance of aircrafts,which also increases the complexity of tool orientation planning in the five-axis machining.It is an essential task to find the collision-free tool orientation when the tool holder is pushed deep into the channel of blisk to increase rigidity and reduce vibration.Since the radius of the holder varies with the height,the line-visibility is no longer applicable when constructing collision-free regions of tool orientation.In this paper,a method of constructing collisionfree regions without interference checking is proposed.The work of finding collision-free regions resorts to solving the local contact curves on the checking surfaces of blisk.And it further transforms into searching the locally tangent points(named critical points)between the holder and surface.Then a tracking-based algorithm is proposed to search the sample critical points on these local contact curves.And the corresponding critical vectors are also calculated synchronously.Besides,the safety allowance,discrete precision and acceptable deviation are introduced in the algorithm to ensure accuracy by controlling the angle between two adjacent critical vectors properly.After that,the searched critical vectors are mapped orderly to two-dimensional space and the collisionfree regions are constructed.This method is finally verified and compared with a referenced method.The results show that the proposed method can efficiently construct collision-free regions for holder under the given accuracy.展开更多
基金supported by grants from the Key Research and Development Project of Guangdong Province(202020012624900001)the National Natural Science Foundation of China(31830097,31802174 and 82041025)+1 种基金the Key Research and Development Project of Guangdong Province(2020B1111320001)the Special fund for the Scientific innovation strategy-construction ofhigh level Academyof Agriculture Science-Prominent Talents(R2020PY-JC001)。
文摘Dear Editor,In the absence of vaccine,the mounting second wave of COVID-19 infections worldwide calls for the rapid development of human neutralizing antibodies to prevent and treat COVID-19(Lee et al.2020).Considering the high cost and long development cycle of human neutralizing antibodies,we turned to anti-SARS-Co V-2 Ig Y for cheap and fast scale up.
基金the National Natural Science Foundation of China(No.51675439)。
文摘Blisks with the integral structure are key parts used in new jet engines to promote the performance of aircrafts,which also increases the complexity of tool orientation planning in the five-axis machining.It is an essential task to find the collision-free tool orientation when the tool holder is pushed deep into the channel of blisk to increase rigidity and reduce vibration.Since the radius of the holder varies with the height,the line-visibility is no longer applicable when constructing collision-free regions of tool orientation.In this paper,a method of constructing collisionfree regions without interference checking is proposed.The work of finding collision-free regions resorts to solving the local contact curves on the checking surfaces of blisk.And it further transforms into searching the locally tangent points(named critical points)between the holder and surface.Then a tracking-based algorithm is proposed to search the sample critical points on these local contact curves.And the corresponding critical vectors are also calculated synchronously.Besides,the safety allowance,discrete precision and acceptable deviation are introduced in the algorithm to ensure accuracy by controlling the angle between two adjacent critical vectors properly.After that,the searched critical vectors are mapped orderly to two-dimensional space and the collisionfree regions are constructed.This method is finally verified and compared with a referenced method.The results show that the proposed method can efficiently construct collision-free regions for holder under the given accuracy.
