The development of wireless sensor network ing, social networking, and wearable sensing techniques has advanced the boundaries of research on understanding so cial dynamics. Collaborative sensing, which utilizes diver...The development of wireless sensor network ing, social networking, and wearable sensing techniques has advanced the boundaries of research on understanding so cial dynamics. Collaborative sensing, which utilizes diver sity sensing and computing abilities across different entities, has become a popular sensing and computing paradigm. In this paper, we first review the history of research in col laborative sensing, which mainly refers to single space col laborative sensing that consists of physical, cyber, and so cial collaborative sensing. Afterward, we extend this concept into crossspace collaborative sensing and propose a general reference framework to demonstrate the distinct mechanism of crossspace collaborative sensing. We also review early works in crossspace collaborative sensing, and study the de tail mechanism based on one typical research work. Finally, although crossspace collaborative sensing is a promising re search area, it "is still in its infancy. Thus, we identify some key research challenges with potential technical details at the end of this paper.展开更多
Symmetry of biological structures can be thought as the repetition of their parts in different positions and orientations. Asymmetry analyses, therefore, focuses on identifying and measuring the location and extent of...Symmetry of biological structures can be thought as the repetition of their parts in different positions and orientations. Asymmetry analyses, therefore, focuses on identifying and measuring the location and extent of symmetry departures in such structures. In the context of geometric morphometrics, a key step when studying morphological variation is the estimation of the symmetric shape. The standard procedure uses the least-squares Procrustes superimposition, which by averaging shape differences often underestimates the symmetry departures thus leading to an inaccurate description of the asymmetry pattern. Moreover, the corresponding asymmetry values are neither geometrically intuitive nor visually perceivable. Methods: In this work, a resistant method for landmark-based asymmetry analysis of individual bilateral symmetric structures in 2D is introduced. A geometrical derivation of this new approach is offered, while its advantages in comparison with the standard method are examined and discussed through a few illustrative examples. Results: Experimental tests on both artificial and real data show that asymmetry is more effectively measured by using the resistant method because the underlying symmetric shape is better estimated. Therefore, the most asymmetric (respectively symmetric) landmarks are better determined through their large (respectively small) residuals. The percentage of asymmetry that is accounted for by each landmark is an additional revealing measure the new method offers which agrees with the displayed results while helping in their biological interpretation. Conclusions: The resistant method is a useful exploratory tool for analyzing shape asymmetry in 2D, and it might be the preferable method whenever a non homogeneous deformation of bilateral symmetric structures is possible. By offering a more detailed and rather exhaustive explanation of the asymmetry pattern, this new approach will hopefully contribute to improve the quality of biological or developmental inferences.展开更多
Projection-type recorders of computer-generated Fourier holograms have potential due to the decreased precision requirements of the optical scheme compared to most known holographic data recorders based on two-beam sc...Projection-type recorders of computer-generated Fourier holograms have potential due to the decreased precision requirements of the optical scheme compared to most known holographic data recorders based on two-beam schemes.In the case of optical memory system development,the reduction factor of the projection scheme requires the application of properly developed optical components.The present report is dedicated to the development of special objectives for the projection scheme of computer-generated Fourier holograms.展开更多
文摘The development of wireless sensor network ing, social networking, and wearable sensing techniques has advanced the boundaries of research on understanding so cial dynamics. Collaborative sensing, which utilizes diver sity sensing and computing abilities across different entities, has become a popular sensing and computing paradigm. In this paper, we first review the history of research in col laborative sensing, which mainly refers to single space col laborative sensing that consists of physical, cyber, and so cial collaborative sensing. Afterward, we extend this concept into crossspace collaborative sensing and propose a general reference framework to demonstrate the distinct mechanism of crossspace collaborative sensing. We also review early works in crossspace collaborative sensing, and study the de tail mechanism based on one typical research work. Finally, although crossspace collaborative sensing is a promising re search area, it "is still in its infancy. Thus, we identify some key research challenges with potential technical details at the end of this paper.
文摘Symmetry of biological structures can be thought as the repetition of their parts in different positions and orientations. Asymmetry analyses, therefore, focuses on identifying and measuring the location and extent of symmetry departures in such structures. In the context of geometric morphometrics, a key step when studying morphological variation is the estimation of the symmetric shape. The standard procedure uses the least-squares Procrustes superimposition, which by averaging shape differences often underestimates the symmetry departures thus leading to an inaccurate description of the asymmetry pattern. Moreover, the corresponding asymmetry values are neither geometrically intuitive nor visually perceivable. Methods: In this work, a resistant method for landmark-based asymmetry analysis of individual bilateral symmetric structures in 2D is introduced. A geometrical derivation of this new approach is offered, while its advantages in comparison with the standard method are examined and discussed through a few illustrative examples. Results: Experimental tests on both artificial and real data show that asymmetry is more effectively measured by using the resistant method because the underlying symmetric shape is better estimated. Therefore, the most asymmetric (respectively symmetric) landmarks are better determined through their large (respectively small) residuals. The percentage of asymmetry that is accounted for by each landmark is an additional revealing measure the new method offers which agrees with the displayed results while helping in their biological interpretation. Conclusions: The resistant method is a useful exploratory tool for analyzing shape asymmetry in 2D, and it might be the preferable method whenever a non homogeneous deformation of bilateral symmetric structures is possible. By offering a more detailed and rather exhaustive explanation of the asymmetry pattern, this new approach will hopefully contribute to improve the quality of biological or developmental inferences.
基金performed as a part of the state assignments of the Ministry of Education and Science of the Russian Federation,No.3.9.2014
文摘Projection-type recorders of computer-generated Fourier holograms have potential due to the decreased precision requirements of the optical scheme compared to most known holographic data recorders based on two-beam schemes.In the case of optical memory system development,the reduction factor of the projection scheme requires the application of properly developed optical components.The present report is dedicated to the development of special objectives for the projection scheme of computer-generated Fourier holograms.