Aperture-dependent motion compensation is important for wide beam Synthetic Aperture Radar(SAR) data processing.This paper studies a wide beam motion compensation algorithm based on frequency division.It takes blocks ...Aperture-dependent motion compensation is important for wide beam Synthetic Aperture Radar(SAR) data processing.This paper studies a wide beam motion compensation algorithm based on frequency division.It takes blocks along azimuth dimension in frequency domain and applies an-gle-variant motion compensation in time domain.With this frequency division based motion com-pensation approach,the effects of aperture-dependent residual phase errors are corrected precisely.The rationale and procedure of this algorithm are introduced in detail.Point targets and images of a P-band airborne SAR with motion errors are simulated to validate this algorithm.Compared with the wide beam motion compensation algorithms based on time division,the proposed algorithm has better performance,especially in terms of high-frequency motion errors.展开更多
An efficient bit rate allocation algorithm for video sequence transmission in motion JPEG2000 is presented. In many cases,the moving portions of video are often the interested regions. Based on tile encoding of JPEG20...An efficient bit rate allocation algorithm for video sequence transmission in motion JPEG2000 is presented. In many cases,the moving portions of video are often the interested regions. Based on tile encoding of JPEG2000,the important regions are discerned by two parameters. One is the complexity of a tile;the other is the motion activity of a tile. Thus an adaptive rate-allocation is re-alized in a lower complexity and the perceptive quality of a frame is improved. Experimental results show the effectiveness of this algorithm.展开更多
Under the initiative of“encouraging 300 million people to participate in ice and snow sports”and the guidance of the‘Evidence-based’policy-making process,this study takes the Hierarchical Model of Leisure Constrai...Under the initiative of“encouraging 300 million people to participate in ice and snow sports”and the guidance of the‘Evidence-based’policy-making process,this study takes the Hierarchical Model of Leisure Constraints as the theoretical framework to empirically explore the constraints influencing the participation of residents in Southern China in ice and snow sports.After factor analysis,the constraint dimension of residents’participation was obtained,and the constraints of participants and non-participants were evaluated and compared by Propensity Score Matching(PSM).The results indicate that Chengdu residents have potential interest in and demand for winter sports,and the constraint dimensions are:facilities and services,companions,time,and personal feelings.The predisposition scores of the experimental group and the control group revealed that the constraints on interest,relevant knowledge and skills,and personal feelings of the participating group were significantly lower than those of the non-participating group,while the other constraints were not significant.We suggest that efforts should be made to increase the effective supply according to local conditions in order to reduce structural constraints,and the social attributes should be integrated into ice and snow sports to resolve the inter-personal constraints.展开更多
文摘Aperture-dependent motion compensation is important for wide beam Synthetic Aperture Radar(SAR) data processing.This paper studies a wide beam motion compensation algorithm based on frequency division.It takes blocks along azimuth dimension in frequency domain and applies an-gle-variant motion compensation in time domain.With this frequency division based motion com-pensation approach,the effects of aperture-dependent residual phase errors are corrected precisely.The rationale and procedure of this algorithm are introduced in detail.Point targets and images of a P-band airborne SAR with motion errors are simulated to validate this algorithm.Compared with the wide beam motion compensation algorithms based on time division,the proposed algorithm has better performance,especially in terms of high-frequency motion errors.
文摘An efficient bit rate allocation algorithm for video sequence transmission in motion JPEG2000 is presented. In many cases,the moving portions of video are often the interested regions. Based on tile encoding of JPEG2000,the important regions are discerned by two parameters. One is the complexity of a tile;the other is the motion activity of a tile. Thus an adaptive rate-allocation is re-alized in a lower complexity and the perceptive quality of a frame is improved. Experimental results show the effectiveness of this algorithm.
基金The National Social Science Foundation of China(17CTY014).
文摘Under the initiative of“encouraging 300 million people to participate in ice and snow sports”and the guidance of the‘Evidence-based’policy-making process,this study takes the Hierarchical Model of Leisure Constraints as the theoretical framework to empirically explore the constraints influencing the participation of residents in Southern China in ice and snow sports.After factor analysis,the constraint dimension of residents’participation was obtained,and the constraints of participants and non-participants were evaluated and compared by Propensity Score Matching(PSM).The results indicate that Chengdu residents have potential interest in and demand for winter sports,and the constraint dimensions are:facilities and services,companions,time,and personal feelings.The predisposition scores of the experimental group and the control group revealed that the constraints on interest,relevant knowledge and skills,and personal feelings of the participating group were significantly lower than those of the non-participating group,while the other constraints were not significant.We suggest that efforts should be made to increase the effective supply according to local conditions in order to reduce structural constraints,and the social attributes should be integrated into ice and snow sports to resolve the inter-personal constraints.
