Let l be a given nonzero integer.The authors give an explicit characterization of the positive integer k that makes the Diophantine equation x2-kxy+y2+lx=0 have infinitely many positive integer solutions(x,y).
Sandwich masonry wall,namely,multi-leaf masonry wall,is widely applied as energy-saving wall since the interlayer between the two outer leaves can act as insulation layer.New types of sandwich walls keep appearing in ...Sandwich masonry wall,namely,multi-leaf masonry wall,is widely applied as energy-saving wall since the interlayer between the two outer leaves can act as insulation layer.New types of sandwich walls keep appearing in research and application,and due to their unique connection patterns,experimental studies should be performed to investigate the mechanical behavior,especially the compressive performance.3 new types of sandwich masonry wall were investigated in this paper,and 3 different technical measures were considered to guarantee the cooperation between the two leaves of the walls.Based on the compression tests of 13 specimens,except for some damage patterns similar with the conventional masonry walls,several new failure patterns are found due to unique connection construction details.Comparisons were made between the tested compression capacity and the theoretical one which was calculated according to the Chinese Code for Design of Masonry Structures.The results indicate that the contributions of the 3 technical measures are different.The modification coefficient(γ)was suggested to evaluate the contribution of the technical measures on the compression capacity,and then a formula was proposed to evaluate the design compression capacity of the new sandwich masonry walls.展开更多
基金the National Natural Science Foundation of China(No.10971184)
文摘Let l be a given nonzero integer.The authors give an explicit characterization of the positive integer k that makes the Diophantine equation x2-kxy+y2+lx=0 have infinitely many positive integer solutions(x,y).
基金This work was supported by Program for New Century Excellent Talents in University(Grant No.NCET-06-0383)Science and Technology Commission of Shanghai,China(Grant No.10231202000).Jiangsu Qixiu Group is also acknowledged.
文摘Sandwich masonry wall,namely,multi-leaf masonry wall,is widely applied as energy-saving wall since the interlayer between the two outer leaves can act as insulation layer.New types of sandwich walls keep appearing in research and application,and due to their unique connection patterns,experimental studies should be performed to investigate the mechanical behavior,especially the compressive performance.3 new types of sandwich masonry wall were investigated in this paper,and 3 different technical measures were considered to guarantee the cooperation between the two leaves of the walls.Based on the compression tests of 13 specimens,except for some damage patterns similar with the conventional masonry walls,several new failure patterns are found due to unique connection construction details.Comparisons were made between the tested compression capacity and the theoretical one which was calculated according to the Chinese Code for Design of Masonry Structures.The results indicate that the contributions of the 3 technical measures are different.The modification coefficient(γ)was suggested to evaluate the contribution of the technical measures on the compression capacity,and then a formula was proposed to evaluate the design compression capacity of the new sandwich masonry walls.