A low-alloyed Mg-2Zn-0.8Sr-0.2Ca matrix composite reinforced by TiC nano-particles was successfully prepared by semi-solid stirring under the assistance of ultrasonic,and then the as-cast composite was hot extruded.Th...A low-alloyed Mg-2Zn-0.8Sr-0.2Ca matrix composite reinforced by TiC nano-particles was successfully prepared by semi-solid stirring under the assistance of ultrasonic,and then the as-cast composite was hot extruded.The results indicated that the volume fraction of dynamical recrystallization and the recrystallized grain size have a certain decline at lower extrusion temperature or rate.The finest grain size of~0.30μm is obtained in the sample extruded at 200℃ and 0.1 mm/s.The as-extruded sample displays a strong basal texture intensity,and the basal texture intensity increases to 5.937 mud while the extrusion temperature increases from 200 to 240℃.The ultra-high mechanical properties(ultimate tensile strength of 480.2 MPa,yield strength of 462 MPa)are obtained after extrusion at 200℃ with a rate of 0.1 mm/s.Among all strengthening mechanisms for the present composite,the grain refinement contributes the most to the increase in strength.A mixture of cleavage facets and dimples were observed in the fracture surfaces of three as-extruded nanocomposites,which explain a mix of brittle-ductile fracture way of the samples.展开更多
This paper studies some programming techniques for low power rendering for 3 D graphics. These techniques are derived from analysis and simulation results of hardware circuits of GPU. Although low power3 D graphics ha...This paper studies some programming techniques for low power rendering for 3 D graphics. These techniques are derived from analysis and simulation results of hardware circuits of GPU. Although low power3 D graphics hardware design has been studied by other researchers,low power programming techniques from hardware perspective have not been investigated in depth. There are many factors that affect 3 D graphics rendering performance,such as the number of vertices,vertex sharing,level of details,texture mapping,and rendering algorithms. An analytical study of graphics rendering workload is performed and the effect of a number of programming tips such as vertex sharing,clock gating and buffering of unmoving or translational objects is deeply studied. The results presented in this paper can be used to guide 3 D graphics programming for optimizing both power consumption and performance.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 51771129, 51401144, and 51771128)the Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi, China+1 种基金the Natural Science Foundation of Shanxi Province, China (Nos. 2015021067 and 201601D011034)the Projects of International Cooperation in Shanxi, China (No. 2017 03D421039)
文摘A low-alloyed Mg-2Zn-0.8Sr-0.2Ca matrix composite reinforced by TiC nano-particles was successfully prepared by semi-solid stirring under the assistance of ultrasonic,and then the as-cast composite was hot extruded.The results indicated that the volume fraction of dynamical recrystallization and the recrystallized grain size have a certain decline at lower extrusion temperature or rate.The finest grain size of~0.30μm is obtained in the sample extruded at 200℃ and 0.1 mm/s.The as-extruded sample displays a strong basal texture intensity,and the basal texture intensity increases to 5.937 mud while the extrusion temperature increases from 200 to 240℃.The ultra-high mechanical properties(ultimate tensile strength of 480.2 MPa,yield strength of 462 MPa)are obtained after extrusion at 200℃ with a rate of 0.1 mm/s.Among all strengthening mechanisms for the present composite,the grain refinement contributes the most to the increase in strength.A mixture of cleavage facets and dimples were observed in the fracture surfaces of three as-extruded nanocomposites,which explain a mix of brittle-ductile fracture way of the samples.
基金Sponsored by the Key Program of National Natural Science Foundation of China(Grant No61136002)the Research Grants from the Shaanxi Provincial Government(Grant Nos.2013KTZB01-07,2014ZS-08 and S2015TQGY0166)the Shaanxi Education Bureau(Grant No.2050205)
文摘This paper studies some programming techniques for low power rendering for 3 D graphics. These techniques are derived from analysis and simulation results of hardware circuits of GPU. Although low power3 D graphics hardware design has been studied by other researchers,low power programming techniques from hardware perspective have not been investigated in depth. There are many factors that affect 3 D graphics rendering performance,such as the number of vertices,vertex sharing,level of details,texture mapping,and rendering algorithms. An analytical study of graphics rendering workload is performed and the effect of a number of programming tips such as vertex sharing,clock gating and buffering of unmoving or translational objects is deeply studied. The results presented in this paper can be used to guide 3 D graphics programming for optimizing both power consumption and performance.