In this paper,a cooperative localization algorithm for autonomous underwater vehicles(AUVs)is proposed.A"parallel"model is adopted to describe the cooperative localization problem instead of the traditional&...In this paper,a cooperative localization algorithm for autonomous underwater vehicles(AUVs)is proposed.A"parallel"model is adopted to describe the cooperative localization problem instead of the traditional"leader-follower"model,and a linear programming associated with convex optimization method is used to deal with the problem.After an unknown-but-bounded model for sensor noise is assumed,bearing and range measurements can be modeled as linear constraints on the configuration space of the AUVs.Merging these constraints induces a convex polyhedron representing the set of all configurations consistent with the sensor measurements.Estimates for the uncertainty in the position of a single AUV or the relative positions of two or more nodes can then be obtained by projecting this polyhedron onto appropriate subspaces of the configuration space.Two different optimization algorithms are given to recover the uncertainty region according to the number of the AUVs.Simulation results are presented for a typical localization example of the AUV formation.The results show that our positioning method offers a good localization accuracy,although a small number of low-cost sensors are needed for each vehicle,and this validates that it is an economical and practical positioning approach compared with the traditional approach.展开更多
The satellite laser ranging （SLR） data quality from the COMPASS was analyzed, and the difference between curve recognition in computer vision and pre-process of SLR data finally proposed a new algorithm for SLR was ...The satellite laser ranging （SLR） data quality from the COMPASS was analyzed, and the difference between curve recognition in computer vision and pre-process of SLR data finally proposed a new algorithm for SLR was discussed data based on curve recognition from points cloud is proposed. The results obtained by the new algorithm are 85 % （or even higher） consistent with that of the screen displaying method, furthermore, the new method can process SLR data automatically, which makes it possible to be used in the development of the COMPASS navigation system.展开更多
The methods and strategies used to screen for syp-hilis and to confirm initially reactive results can vary significantly across clinical laboratories. While the performance characteristics of these different appro-ach...The methods and strategies used to screen for syp-hilis and to confirm initially reactive results can vary significantly across clinical laboratories. While the performance characteristics of these different appro-aches have been evaluated by multiple studies, there is not, as of yet, a single, universally recommendedalgorithm for syphilis testing. To clarify the currently available options for syphilis testing, this update will summarize the clinical challenges to diagnosis, review the specific performance characteristics of treponemal and non-treponemal tests, and fnally, summarize select studies published over the past decade which have evaluated these approaches. Specifcally, this review will discuss the traditional and reverse sequence syphilis screening algorithms commonly used in the United States, alongside a discussion of the European Centre for Disease Prevention and Control syphilis algorithm. Ultimately, in the United States, the decision of which algorithm to use is largely dependent on laboratory resources, the local incidence of syphilis and patient demographics. Key words： Syphilis; Treponemal infection; Immuno-assay; Reverse sequence screening; Rapid plasma regain; Treponema pallidum particle agglutination test; Automation; Algorithm; Primary infection; Late latent infection展开更多
基金Supported by National High Technology Research and Development Program of China(863 Program)(2007AA809502C)National Natural Science Foundation of China(50979093)Program for New Century Excellent Talents in University(NCET-06-0877)
文摘In this paper,a cooperative localization algorithm for autonomous underwater vehicles(AUVs)is proposed.A"parallel"model is adopted to describe the cooperative localization problem instead of the traditional"leader-follower"model,and a linear programming associated with convex optimization method is used to deal with the problem.After an unknown-but-bounded model for sensor noise is assumed,bearing and range measurements can be modeled as linear constraints on the configuration space of the AUVs.Merging these constraints induces a convex polyhedron representing the set of all configurations consistent with the sensor measurements.Estimates for the uncertainty in the position of a single AUV or the relative positions of two or more nodes can then be obtained by projecting this polyhedron onto appropriate subspaces of the configuration space.Two different optimization algorithms are given to recover the uncertainty region according to the number of the AUVs.Simulation results are presented for a typical localization example of the AUV formation.The results show that our positioning method offers a good localization accuracy,although a small number of low-cost sensors are needed for each vehicle,and this validates that it is an economical and practical positioning approach compared with the traditional approach.
文摘The satellite laser ranging （SLR） data quality from the COMPASS was analyzed, and the difference between curve recognition in computer vision and pre-process of SLR data finally proposed a new algorithm for SLR was discussed data based on curve recognition from points cloud is proposed. The results obtained by the new algorithm are 85 % （or even higher） consistent with that of the screen displaying method, furthermore, the new method can process SLR data automatically, which makes it possible to be used in the development of the COMPASS navigation system.
文摘The methods and strategies used to screen for syp-hilis and to confirm initially reactive results can vary significantly across clinical laboratories. While the performance characteristics of these different appro-aches have been evaluated by multiple studies, there is not, as of yet, a single, universally recommendedalgorithm for syphilis testing. To clarify the currently available options for syphilis testing, this update will summarize the clinical challenges to diagnosis, review the specific performance characteristics of treponemal and non-treponemal tests, and fnally, summarize select studies published over the past decade which have evaluated these approaches. Specifcally, this review will discuss the traditional and reverse sequence syphilis screening algorithms commonly used in the United States, alongside a discussion of the European Centre for Disease Prevention and Control syphilis algorithm. Ultimately, in the United States, the decision of which algorithm to use is largely dependent on laboratory resources, the local incidence of syphilis and patient demographics. Key words： Syphilis; Treponemal infection; Immuno-assay; Reverse sequence screening; Rapid plasma regain; Treponema pallidum particle agglutination test; Automation; Algorithm; Primary infection; Late latent infection
