A novel iterative technique, the phase descent search detection was proposed. This technique constrained the solution (PDS) algorithm, for M-ary phase shift keying (M-PSK) symbols to have a unit magnitude and it w...A novel iterative technique, the phase descent search detection was proposed. This technique constrained the solution (PDS) algorithm, for M-ary phase shift keying (M-PSK) symbols to have a unit magnitude and it was based on coordinate descent iterations where coordinates were the unknown symbol phases. The PDS algorithm, together with a descent local search (also implemented as a version of the PDS algorithm), was used multiple times with different initializations in a proposed multiple phase detector; the solution with the minimum cost was then chosen as the final solution. The simulation results show that for highly loaded multiuser scenarios, the proposed technique has a detection performance that is close to the single-user bound. The results also show that the multiple phase detector allows detection in highly overloaded scenarios and it exhibits near-far resistance. In particular, the detector has a performance that is significantly better, and complexity that is significantly lower, than that of the detector based on semi-definite relaxation.展开更多
Numerous experimental and theoretical studies on recycled aggregate concrete have been carried out in China in the past 10 years.This paper provides a comprehensive review of the related findings of research on the me...Numerous experimental and theoretical studies on recycled aggregate concrete have been carried out in China in the past 10 years.This paper provides a comprehensive review of the related findings of research on the mechanical properties of RAC in China.The influences of the RCA on the strength and deformation characteristics of concrete,the statistical characteristics for the strength of RAC,fracture energy,stress-strain relationships under uniaxial compression,uniaxial tension as well as pure shear,and the residual strength of RAC after exposure to high temperatures,the bond between RAC and different kinds of steel rebar were also reviewed.Furthermore,some recent studies on the numerical simulation of the failure mechanism for RAC at the meso-structure level were discussed.展开更多
文摘A novel iterative technique, the phase descent search detection was proposed. This technique constrained the solution (PDS) algorithm, for M-ary phase shift keying (M-PSK) symbols to have a unit magnitude and it was based on coordinate descent iterations where coordinates were the unknown symbol phases. The PDS algorithm, together with a descent local search (also implemented as a version of the PDS algorithm), was used multiple times with different initializations in a proposed multiple phase detector; the solution with the minimum cost was then chosen as the final solution. The simulation results show that for highly loaded multiuser scenarios, the proposed technique has a detection performance that is close to the single-user bound. The results also show that the multiple phase detector allows detection in highly overloaded scenarios and it exhibits near-far resistance. In particular, the detector has a performance that is significantly better, and complexity that is significantly lower, than that of the detector based on semi-definite relaxation.
基金supported by the National Natural Science Foundation of China (Grant No. 51178340)the Shanghai Science and Technology Committee (Grant No. 10231202000)the New Century Excellent Talentsin China Ministry of Education Project (Grant No. NCET-06-0383)
文摘Numerous experimental and theoretical studies on recycled aggregate concrete have been carried out in China in the past 10 years.This paper provides a comprehensive review of the related findings of research on the mechanical properties of RAC in China.The influences of the RCA on the strength and deformation characteristics of concrete,the statistical characteristics for the strength of RAC,fracture energy,stress-strain relationships under uniaxial compression,uniaxial tension as well as pure shear,and the residual strength of RAC after exposure to high temperatures,the bond between RAC and different kinds of steel rebar were also reviewed.Furthermore,some recent studies on the numerical simulation of the failure mechanism for RAC at the meso-structure level were discussed.