Plastic forming is one of enabling and fundamental technologies in advanced manufacturing chains. Design optimization is a critical way to improve the performance of the forming system, exploit the advantages of high ...Plastic forming is one of enabling and fundamental technologies in advanced manufacturing chains. Design optimization is a critical way to improve the performance of the forming system, exploit the advantages of high productivity, high product quality, low production cost and short time to market and develop precise, accurate, green, and intelligent(smart) plastic forming technology. However, plastic forming is quite complicated, relating to multi-physics field coupling,multi-factor influence, multi-defect constraint, and triple nonlinear, etc., and the design optimization for plastic forming involves multi-objective, multi-parameter, multi-constraint, nonlinear,high-dimensionality, non-continuity, time-varying, and uncertainty, etc. Therefore, how to achieve accurate and efficient design optimization of products, equipment, tools/dies, and processing as well as materials characterization has always been the research frontier and focus in the field of engineering and manufacturing. In recent years, with the rapid development of computing science, data science and internet of things(Io T), the theories and technologies of design optimization have attracted more and more attention, and developed rapidly in forming process. Accordingly, this paper first introduced the framework of design optimization for plastic forming. Then, focusing on the key problems of design optimization, such as numerical model and optimization algorithm,this paper summarized the research progress on the development and application of the theories and technologies about design optimization in forming process, including deterministic and uncertain optimization. Moreover, the applicability of various modeling methods and optimization algorithms was elaborated in solving the design optimization problems of plastic forming. Finally, considering the development trends of forming technology, this paper discusses some challenges of design optimization that may need to be solved and faced in forming process.展开更多
Staphylococcal Enterotoxin B (SEB) is considered a potential biological weapon. It is toxic by both inhalation and ingestion. Effects of ingestion include fever, vomiting and diarrhoea, while inhalation may additional...Staphylococcal Enterotoxin B (SEB) is considered a potential biological weapon. It is toxic by both inhalation and ingestion. Effects of ingestion include fever, vomiting and diarrhoea, while inhalation may additionally result in chest pain, dyspnoea, pulmonary oedema and respiratory failure. Severe exposure may be fatal and treatment relies on symptomatic support. At a cellular level, SEB up-regulates T-cell proliferation leading to a pathological inflammatory response. Deguelin, a rotenoid isolated from the African plant Mundulea sericea (Leguminosae), has been shown to reduce cellular proliferation by inhibiting the phosphoinositide 3-kinase/Akt (PI3K/Akt) signalling pathway. Using isolated murine splenocytes, we have demonstrated that treatment with deguelin reduces SEB inducing T cell proliferation by 60%. Deguelin treatment also decreased IL-2 and CCL2 secretion by splenocytes exposed to SEB. We demonstrate that targeting cellular proliferation can significantly reduce inflammation after SEB exposure and suggest that anti-proliferatives may have a role as potential generic medical counter measures if superantigens are used as biological weapons.展开更多
High order approximations of the vortical flowfield and resulting aerodynamic coefficients of complex supersonic vortical flows,are computed using the Implicit Parabolized Navier-Stokes solver(IMPNS).Third and fifth o...High order approximations of the vortical flowfield and resulting aerodynamic coefficients of complex supersonic vortical flows,are computed using the Implicit Parabolized Navier-Stokes solver(IMPNS).Third and fifth order Weighted Essentially Non-oscillating(WENO)schemes for evenly spaced and for stretched structured meshes are employed for the approximate Riemann solution of the inviscid cross flow fluxes.An approximate Riemann solution is obtained using the Osher and Solomon solver and the one-equation Spalart-Allmaras turbulence model is modified for an improved strain-vorticity approximation.Results indicate that even on much coarser meshes the 5th order PNS-WENO-Spalart-Allmaras approach may achieve results that are superior to previously published full Navier-Stokes solutions that employ a two-equation RANS model but the additional computational demand of schemes for non-uniform grids,may not be justifiable for smoothly varying meshes.The proposed PNS-WENO scheme combination provides a novel approach that is fast,accurate and robust,and that can substantially reduce numerical dissipation and improve the resolution of the vortical structures.展开更多
Next generation high-power laser facilities are expected to generate hundreds-of-MeV proton beams and operate at multiHz repetition rates, presenting opportunities for medical, industrial and scientific applications r...Next generation high-power laser facilities are expected to generate hundreds-of-MeV proton beams and operate at multiHz repetition rates, presenting opportunities for medical, industrial and scientific applications requiring bright pulses of energetic ions. Characterizing the spectro-spatial profile of these ions at high repetition rates in the harsh radiation environments created by laser–plasma interactions remains challenging but is paramount for further source development.To address this, we present a compact scintillating fiber imaging spectrometer based on the tomographic reconstruction of proton energy deposition in a layered fiber array. Modeling indicates that spatial resolution of approximately 1 mm and energy resolution of less than 10% at proton energies of more than 20 MeV are readily achievable with existing 100 μm diameter fibers. Measurements with a prototype beam-profile monitor using 500 μm fibers demonstrate active readouts with invulnerability to electromagnetic pulses, and less than 100 Gy sensitivity. The performance of the full instrument concept is explored with Monte Carlo simulations, accurately reconstructing a proton beam with a multiple-component spectro-spatial profile.展开更多
基金the National Natural Science Foundation of China (Nos. 51775441&51835011)the National Science Fund for Excellent Young Scholars (No.51522509)Research Fund of the State Key Laboratory of Solidification Processing (NWPU) of China (KP201608)。
文摘Plastic forming is one of enabling and fundamental technologies in advanced manufacturing chains. Design optimization is a critical way to improve the performance of the forming system, exploit the advantages of high productivity, high product quality, low production cost and short time to market and develop precise, accurate, green, and intelligent(smart) plastic forming technology. However, plastic forming is quite complicated, relating to multi-physics field coupling,multi-factor influence, multi-defect constraint, and triple nonlinear, etc., and the design optimization for plastic forming involves multi-objective, multi-parameter, multi-constraint, nonlinear,high-dimensionality, non-continuity, time-varying, and uncertainty, etc. Therefore, how to achieve accurate and efficient design optimization of products, equipment, tools/dies, and processing as well as materials characterization has always been the research frontier and focus in the field of engineering and manufacturing. In recent years, with the rapid development of computing science, data science and internet of things(Io T), the theories and technologies of design optimization have attracted more and more attention, and developed rapidly in forming process. Accordingly, this paper first introduced the framework of design optimization for plastic forming. Then, focusing on the key problems of design optimization, such as numerical model and optimization algorithm,this paper summarized the research progress on the development and application of the theories and technologies about design optimization in forming process, including deterministic and uncertain optimization. Moreover, the applicability of various modeling methods and optimization algorithms was elaborated in solving the design optimization problems of plastic forming. Finally, considering the development trends of forming technology, this paper discusses some challenges of design optimization that may need to be solved and faced in forming process.
文摘Staphylococcal Enterotoxin B (SEB) is considered a potential biological weapon. It is toxic by both inhalation and ingestion. Effects of ingestion include fever, vomiting and diarrhoea, while inhalation may additionally result in chest pain, dyspnoea, pulmonary oedema and respiratory failure. Severe exposure may be fatal and treatment relies on symptomatic support. At a cellular level, SEB up-regulates T-cell proliferation leading to a pathological inflammatory response. Deguelin, a rotenoid isolated from the African plant Mundulea sericea (Leguminosae), has been shown to reduce cellular proliferation by inhibiting the phosphoinositide 3-kinase/Akt (PI3K/Akt) signalling pathway. Using isolated murine splenocytes, we have demonstrated that treatment with deguelin reduces SEB inducing T cell proliferation by 60%. Deguelin treatment also decreased IL-2 and CCL2 secretion by splenocytes exposed to SEB. We demonstrate that targeting cellular proliferation can significantly reduce inflammation after SEB exposure and suggest that anti-proliferatives may have a role as potential generic medical counter measures if superantigens are used as biological weapons.
文摘High order approximations of the vortical flowfield and resulting aerodynamic coefficients of complex supersonic vortical flows,are computed using the Implicit Parabolized Navier-Stokes solver(IMPNS).Third and fifth order Weighted Essentially Non-oscillating(WENO)schemes for evenly spaced and for stretched structured meshes are employed for the approximate Riemann solution of the inviscid cross flow fluxes.An approximate Riemann solution is obtained using the Osher and Solomon solver and the one-equation Spalart-Allmaras turbulence model is modified for an improved strain-vorticity approximation.Results indicate that even on much coarser meshes the 5th order PNS-WENO-Spalart-Allmaras approach may achieve results that are superior to previously published full Navier-Stokes solutions that employ a two-equation RANS model but the additional computational demand of schemes for non-uniform grids,may not be justifiable for smoothly varying meshes.The proposed PNS-WENO scheme combination provides a novel approach that is fast,accurate and robust,and that can substantially reduce numerical dissipation and improve the resolution of the vortical structures.
基金financially supported by STFC,Dstl and EPSRC(grant numbers EP/R006202/1,EP/V049232/1 and EP/P020607/1)by Laserlab-Europe(grant agreement number 871124,European Union’s Horizon 2020 research and innovation program).
文摘Next generation high-power laser facilities are expected to generate hundreds-of-MeV proton beams and operate at multiHz repetition rates, presenting opportunities for medical, industrial and scientific applications requiring bright pulses of energetic ions. Characterizing the spectro-spatial profile of these ions at high repetition rates in the harsh radiation environments created by laser–plasma interactions remains challenging but is paramount for further source development.To address this, we present a compact scintillating fiber imaging spectrometer based on the tomographic reconstruction of proton energy deposition in a layered fiber array. Modeling indicates that spatial resolution of approximately 1 mm and energy resolution of less than 10% at proton energies of more than 20 MeV are readily achievable with existing 100 μm diameter fibers. Measurements with a prototype beam-profile monitor using 500 μm fibers demonstrate active readouts with invulnerability to electromagnetic pulses, and less than 100 Gy sensitivity. The performance of the full instrument concept is explored with Monte Carlo simulations, accurately reconstructing a proton beam with a multiple-component spectro-spatial profile.
