The roundabouts are widely used in China,some of which have central islands as scenic spots.The crosswalks connecting to the central islands,normally full of pedestrians,have negative impact on roundabout capability a...The roundabouts are widely used in China,some of which have central islands as scenic spots.The crosswalks connecting to the central islands,normally full of pedestrians,have negative impact on roundabout capability and pedestrian safety.Therefore,this study proposes a fuzzy cellular automata(FCA)model to explore the safety and efficiency impacts of pedestrian-vehicle conflicts at a two-lane roundabout.To reason the decision-making process of individual drivers before crosswalks,membership functions in the fuzzy inference system were calibrated with field data conducted in Changsha,China.Using specific indicators of efficiency and safety performance,it was shown that circulating vehicles can move smoothly in low traffic flow,but the roundabout system is prone to the traffic congestion if traffic flow reaches to a certain level.Also,the high yielding rate of drivers has a negative impact on the traffic efficiency but can improve pedestrian safety.Furthermore,a pedestrian restriction measure was deduced for the roundabout crosswalk from the FCA model and national guideline of setting traffic lights.展开更多
The co-adaptability theoretical solution to conflicting events in construction engineering projects has three problems. First, the transformation of constraint conditions of theoretical solution is very difficult in p...The co-adaptability theoretical solution to conflicting events in construction engineering projects has three problems. First, the transformation of constraint conditions of theoretical solution is very difficult in practical engineering applications; second, some coefficients are difficult to be determined; third, there are overfull circular arithmetic operations involved in it. To resolve these problems, a new method to reduce the theoretical solution complications is proposed. By analyzing the operating mechanism of theoretical solution model, redundancies in the theoretical solution can be eliminated, and the ISM mapping with the co-adaptability solution can be set up. Based on this approach, a procedure to solve practical conflicting events in construction projects is established by replacing characteristic variables with mathematic variables. The research results show that the procedure can replace the co-adaptability theoretical solution effectively and solve practical conflicting events in construction projects.展开更多
The advances accelerated by next-generation sequencing and long-read sequencing technologies continue to provide an impetus for plant phylogenetic study.In the past decade,a large number of phylogenetic studies adopti...The advances accelerated by next-generation sequencing and long-read sequencing technologies continue to provide an impetus for plant phylogenetic study.In the past decade,a large number of phylogenetic studies adopting hundreds to thousands of genes across a wealth of clades have emerged and ushered plant phylogenetics and evolution into a new era.In the meantime,a roadmap for researchers when making decisions across different approaches for their phylogenomic research design is imminent.This review focuses on the utility of genomic data(from organelle genomes,to both reduced representation sequencing and whole-genome sequencing) in phylogenetic and evolutionary investigations,describes the baseline methodology of experimental and analytical procedures,and summarizes recent progress in flowering plant phylogenomics at the ordinal,familial,tribal,and lower levels.We also discuss the challenges,such as the adverse impact on orthology inference and phylogenetic reconstruction raised from systematic errors,and underlying biological factors,such as whole-genome duplication,hybridization/introgression,and incomplete lineage sorting,together suggesting that a bifurcating tree may not be the best model for the tree of life.Finally,we discuss promising avenues for future plant phylogenomic studies.展开更多
基金Project(2020YFB1600400)supported by the National Key Research and Development Program of ChinaProject(2019JJ50837)supported by the Natural Science Foundation of Hunan Province,ChinaProject(71801227)supported by the National Natural Science Foundation of China。
文摘The roundabouts are widely used in China,some of which have central islands as scenic spots.The crosswalks connecting to the central islands,normally full of pedestrians,have negative impact on roundabout capability and pedestrian safety.Therefore,this study proposes a fuzzy cellular automata(FCA)model to explore the safety and efficiency impacts of pedestrian-vehicle conflicts at a two-lane roundabout.To reason the decision-making process of individual drivers before crosswalks,membership functions in the fuzzy inference system were calibrated with field data conducted in Changsha,China.Using specific indicators of efficiency and safety performance,it was shown that circulating vehicles can move smoothly in low traffic flow,but the roundabout system is prone to the traffic congestion if traffic flow reaches to a certain level.Also,the high yielding rate of drivers has a negative impact on the traffic efficiency but can improve pedestrian safety.Furthermore,a pedestrian restriction measure was deduced for the roundabout crosswalk from the FCA model and national guideline of setting traffic lights.
基金Beijing Municipal Government Build Projectsupported by the China Post-Doctoral Science Foundation (Grant No. 20070420347)the Soft Science Foundation of Shanxi Province of China (Grant No. 2005KR121)
文摘The co-adaptability theoretical solution to conflicting events in construction engineering projects has three problems. First, the transformation of constraint conditions of theoretical solution is very difficult in practical engineering applications; second, some coefficients are difficult to be determined; third, there are overfull circular arithmetic operations involved in it. To resolve these problems, a new method to reduce the theoretical solution complications is proposed. By analyzing the operating mechanism of theoretical solution model, redundancies in the theoretical solution can be eliminated, and the ISM mapping with the co-adaptability solution can be set up. Based on this approach, a procedure to solve practical conflicting events in construction projects is established by replacing characteristic variables with mathematic variables. The research results show that the procedure can replace the co-adaptability theoretical solution effectively and solve practical conflicting events in construction projects.
基金supported by the Priority Research Program of the Chinese Academy of Sciences (CAS) (Grant No.XDB31000000)Large-scale Scientific Facilities of the CAS (Grant No.2017LSF-GBOWS-2)。
文摘The advances accelerated by next-generation sequencing and long-read sequencing technologies continue to provide an impetus for plant phylogenetic study.In the past decade,a large number of phylogenetic studies adopting hundreds to thousands of genes across a wealth of clades have emerged and ushered plant phylogenetics and evolution into a new era.In the meantime,a roadmap for researchers when making decisions across different approaches for their phylogenomic research design is imminent.This review focuses on the utility of genomic data(from organelle genomes,to both reduced representation sequencing and whole-genome sequencing) in phylogenetic and evolutionary investigations,describes the baseline methodology of experimental and analytical procedures,and summarizes recent progress in flowering plant phylogenomics at the ordinal,familial,tribal,and lower levels.We also discuss the challenges,such as the adverse impact on orthology inference and phylogenetic reconstruction raised from systematic errors,and underlying biological factors,such as whole-genome duplication,hybridization/introgression,and incomplete lineage sorting,together suggesting that a bifurcating tree may not be the best model for the tree of life.Finally,we discuss promising avenues for future plant phylogenomic studies.