A CFD-based Numerical Virtual Flight(NVF)simulator is presented,which integrates an unsteady flow solver on moving hybrid grids,a Rigid-Body Dynamics(RBD)solver and a module of the Flight Control System(FCS).A techni...A CFD-based Numerical Virtual Flight(NVF)simulator is presented,which integrates an unsteady flow solver on moving hybrid grids,a Rigid-Body Dynamics(RBD)solver and a module of the Flight Control System(FCS).A technique of dynamic hybrid grids is developed to control the active control surfaces with body morphing,with a technique of parallel unstructured dynamic overlapping grids generating proper moving grids over the deflecting control surfaces(e.g.the afterbody rudders of a missile).For the flow/kinematic coupled problems,the 6 Degree-Of-Freedom(DOF)equations are solved by an explicit or implicit method coupled with the URANS CFD solver.The module of the control law is explicitly coupled into the NVF simulator and then improved by the simulation of the pitching maneuver process of a maneuverable missile model.A nonlinear dynamic inversion method is then implemented to design the control law for the pitching process of the maneuverable missile model.Simulations and analysis of the pitching maneuver process are carried out by the NVF simulator to improve the flight control law.Higher control response performance is obtained by adjusting the gain factors and adding an integrator into the control loop.展开更多
目的 :分析细胞因子对外周血单核细胞 L IGHT基因的诱导表达 ,并克隆人 L IGHT基因。方法 :采用新鲜健康人外周血单核细胞 (PMBC) ,分别以 L PS、TNFα、IL - 2、IFN-γ及 PMA刺激以诱导 L IGHT基因表达 ,RT- PCR分析 PMBC内L IGHT基因...目的 :分析细胞因子对外周血单核细胞 L IGHT基因的诱导表达 ,并克隆人 L IGHT基因。方法 :采用新鲜健康人外周血单核细胞 (PMBC) ,分别以 L PS、TNFα、IL - 2、IFN-γ及 PMA刺激以诱导 L IGHT基因表达 ,RT- PCR分析 PMBC内L IGHT基因转录表达。采用 PCR产物直接克隆法克隆人全长 L IGHT基因及其胞外区编码基因 ,并对胞外区编码基因进行大肠杆菌表达。 结果 :当用 IFN-γ和 PMA刺激 PMBC后 4 8h,可诱导 L IGHT基因的明显表达 ,而 L PS、IL - 2和 TNFα则不能诱导。克隆的人 L IGHT全长基因及 L IGHT胞外区编码基因 ,经过 DNA序列测定证实基因序列与文献报道一致。 L IGHT基因胞外区在大肠杆菌获得一定程度的表达。 结论 :本研究对人 L IGHT基因及其胞外区编码基因进行了克隆和表达 。展开更多
Background The pathogenesis of autism spectrum disorders remains elusive and currently there are no diagnostic or pre-dictive biomarkers in autism available. Proteomic profiling has been used in a wide range of neurod...Background The pathogenesis of autism spectrum disorders remains elusive and currently there are no diagnostic or pre-dictive biomarkers in autism available. Proteomic profiling has been used in a wide range of neurodevelopmental disorder studies, which could produce deeper perceptions of the molecular bases behind certain disease and potentially becomes useful in discovering biomarkers in autism spectrum disorders. Methods Serum samples were collected from autistic children about 3 years old in age (n = 32) and healthy controls (n = 20) in similar age and gender. The samples were identified specific proteins that are diff erentially expressed by magnetic bead-based pre-fractionation and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-ToF-MS). Results Eight protein peaks were significantly different in autistic children from the healthy controls (P < 0.0001). The two peaks with the most significant diff erences were 6428 and 7758 Da in size. Conclusion According to diff erences in serum protein profiles between the autistic children and healthy controls, this study identified a set of diff erentially expressed proteins those are significant for further evaluation and might function as biomark-ers in autism.展开更多
Rotor-to-rotor interaction among neighboring rotors of a multirotor has great significance for aerodynamically efficient multirotor design. Current research is conducted to analyze aerodynamic performance of different...Rotor-to-rotor interaction among neighboring rotors of a multirotor has great significance for aerodynamically efficient multirotor design. Current research is conducted to analyze aerodynamic performance of different octocopter configurations amid hover and forward flight. Conventional and coaxial configurations are studied and a hybrid configuration is also proposed to rectify the disadvantages associated with the earlier two. Comparison is carried out for the aforementioned configurations along with comparison of coaxial and hybrid octocopters with bigger diameter rotors in the same confined space for high thrust requirement missions. Vertical spacing of coaxial configuration is also studied. Virtual Blade Method (VBM) is considered herein due to its great computational efficiency. The results show that there are 11.89% and 14.22% loss in thrust for coaxial octocopter compared to conventional and hybrid configurations with normal size rotors and 15.61% loss compared to hybrid configuration with bigger rotors in hover, whereas coaxial square configuration performs the worst in forward flight with a lift loss of 9.1%, 14.77% and 18.8% compared to coaxial diamond, conventional and hybrid configurations with normal size rotors and 9.96% and 17.82% loss compared to coaxial diamond and hybrid configurations with bigger rotors. Combined FM shows that hybrid configuration outperforms other octocopter configurations in overall aerodynamic performance.展开更多
基金supported partially by National Key Research and Development Program (No. 2016YFB0200701)National Natural Science Foundation of China (Nos. 11532016 and 11672324)
文摘A CFD-based Numerical Virtual Flight(NVF)simulator is presented,which integrates an unsteady flow solver on moving hybrid grids,a Rigid-Body Dynamics(RBD)solver and a module of the Flight Control System(FCS).A technique of dynamic hybrid grids is developed to control the active control surfaces with body morphing,with a technique of parallel unstructured dynamic overlapping grids generating proper moving grids over the deflecting control surfaces(e.g.the afterbody rudders of a missile).For the flow/kinematic coupled problems,the 6 Degree-Of-Freedom(DOF)equations are solved by an explicit or implicit method coupled with the URANS CFD solver.The module of the control law is explicitly coupled into the NVF simulator and then improved by the simulation of the pitching maneuver process of a maneuverable missile model.A nonlinear dynamic inversion method is then implemented to design the control law for the pitching process of the maneuverable missile model.Simulations and analysis of the pitching maneuver process are carried out by the NVF simulator to improve the flight control law.Higher control response performance is obtained by adjusting the gain factors and adding an integrator into the control loop.
文摘目的 :分析细胞因子对外周血单核细胞 L IGHT基因的诱导表达 ,并克隆人 L IGHT基因。方法 :采用新鲜健康人外周血单核细胞 (PMBC) ,分别以 L PS、TNFα、IL - 2、IFN-γ及 PMA刺激以诱导 L IGHT基因表达 ,RT- PCR分析 PMBC内L IGHT基因转录表达。采用 PCR产物直接克隆法克隆人全长 L IGHT基因及其胞外区编码基因 ,并对胞外区编码基因进行大肠杆菌表达。 结果 :当用 IFN-γ和 PMA刺激 PMBC后 4 8h,可诱导 L IGHT基因的明显表达 ,而 L PS、IL - 2和 TNFα则不能诱导。克隆的人 L IGHT全长基因及 L IGHT胞外区编码基因 ,经过 DNA序列测定证实基因序列与文献报道一致。 L IGHT基因胞外区在大肠杆菌获得一定程度的表达。 结论 :本研究对人 L IGHT基因及其胞外区编码基因进行了克隆和表达 。
文摘Background The pathogenesis of autism spectrum disorders remains elusive and currently there are no diagnostic or pre-dictive biomarkers in autism available. Proteomic profiling has been used in a wide range of neurodevelopmental disorder studies, which could produce deeper perceptions of the molecular bases behind certain disease and potentially becomes useful in discovering biomarkers in autism spectrum disorders. Methods Serum samples were collected from autistic children about 3 years old in age (n = 32) and healthy controls (n = 20) in similar age and gender. The samples were identified specific proteins that are diff erentially expressed by magnetic bead-based pre-fractionation and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-ToF-MS). Results Eight protein peaks were significantly different in autistic children from the healthy controls (P < 0.0001). The two peaks with the most significant diff erences were 6428 and 7758 Da in size. Conclusion According to diff erences in serum protein profiles between the autistic children and healthy controls, this study identified a set of diff erentially expressed proteins those are significant for further evaluation and might function as biomark-ers in autism.
基金supported by the National Natural Science Foundation of China(No.11972190).
文摘Rotor-to-rotor interaction among neighboring rotors of a multirotor has great significance for aerodynamically efficient multirotor design. Current research is conducted to analyze aerodynamic performance of different octocopter configurations amid hover and forward flight. Conventional and coaxial configurations are studied and a hybrid configuration is also proposed to rectify the disadvantages associated with the earlier two. Comparison is carried out for the aforementioned configurations along with comparison of coaxial and hybrid octocopters with bigger diameter rotors in the same confined space for high thrust requirement missions. Vertical spacing of coaxial configuration is also studied. Virtual Blade Method (VBM) is considered herein due to its great computational efficiency. The results show that there are 11.89% and 14.22% loss in thrust for coaxial octocopter compared to conventional and hybrid configurations with normal size rotors and 15.61% loss compared to hybrid configuration with bigger rotors in hover, whereas coaxial square configuration performs the worst in forward flight with a lift loss of 9.1%, 14.77% and 18.8% compared to coaxial diamond, conventional and hybrid configurations with normal size rotors and 9.96% and 17.82% loss compared to coaxial diamond and hybrid configurations with bigger rotors. Combined FM shows that hybrid configuration outperforms other octocopter configurations in overall aerodynamic performance.
