In floristic research,the grid mapping method is a crucial and highly effective tool for investigating the flora of specific regions.This methodology aids in the collection of comprehensive data,thereby promoting a th...In floristic research,the grid mapping method is a crucial and highly effective tool for investigating the flora of specific regions.This methodology aids in the collection of comprehensive data,thereby promoting a thorough understanding of regional plant diversity.This paper presents findings from a grid mapping study conducted in the Surkhan-Sherabad botanical-geographic region(SShBGR),acknowledged as one of the major floristic areas in southwestern Uzbekistan.Using an expansive dataset of 14,317 records comprised of herbarium specimens and field diary entries collected from 1897 to 2023,we evaluated the stages and seasonal dynamics of data accumulation,species richness(SR),and collection density(CD)within 5 km×5 km grid cells.We further examined the taxonomic and life form composition of the region's flora.Our analysis revealed that the grid mapping phase(2021–2023)produced a significantly greater volume of specimens and taxonomic diversity compared with other periods(1897–1940,1941–1993,and 1994–2020).Field research spanned 206 grid cells during 2021–2023,resulting in 11,883 samples,including 6469 herbarium specimens and 5414 field records.Overall,fieldwork covered 251 of the 253 grid cells within the SShBGR.Notably,the highest species diversity was documented in the B198 grid cell,recording 160 species.In terms of collection density,the E198 grid cell produced 475 samples.Overall,we identified 1053 species distributed across 439 genera and 78 families in the SShBGR.The flora of this region aligned significantly with the dominant families commonly found in the Holarctic,highlighting vital ecological connections.Among our findings,the Asteraceae family was the most polymorphic,with 147 species,followed by the continually stable and diverse Poaceae,Fabaceae,Brassicaceae,and Amaranthaceae.Besides,our analysis revealed a predominance of therophyte life forms,which constituted 52%(552 species)of the total flora.The findings underscore the necessity for continual data collection efforts to further enhance our understanding of the biodiversity in the SShBGR.The results of this study demonstrated that the application of grid-based mapping in floristic studies proves to be an effective tool for assessing biodiversity and identifying key taxonomic groups.展开更多
For the mobile robot path planning under the complex environment,ant colony optimization with artificial potential field based on grid map is proposed to avoid traditional ant colony algorithm's poor convergence a...For the mobile robot path planning under the complex environment,ant colony optimization with artificial potential field based on grid map is proposed to avoid traditional ant colony algorithm's poor convergence and local optimum.Firstly,the pheromone updating mechanism of ant colony is designed by a hybrid strategy of global map updating and local grids updating.Then,some angles between the vectors of artificial potential field and the orientations of current grid are introduced to calculate the visibility of eight-neighbor cells of cellular automata,which are adopted as ant colony's inspiring factor to calculate the transition probability based on the pseudo-random transition rule cellular automata.Finally,mobile robot dynamic path planning and the simulation experiments are completed by this algorithm,and the experimental results show that the method is feasible and effective.展开更多
This article presents information on the study of the flora of Uzbekistan based on grid system mapping. The urban flora of the city of Bukhara was researched in it. As a result of research, the territory of Bukhara ci...This article presents information on the study of the flora of Uzbekistan based on grid system mapping. The urban flora of the city of Bukhara was researched in it. As a result of research, the territory of Bukhara city was divided into 85 indexes based on 1 × 1 km<sup>2</sup> grid mapping system. The diversity and density of species in the indexes are determined. The influence of anthropogenic factors on the diversity of species in the indexes is determined.展开更多
针对现有环境感知技术在毫米波通信信号带宽受限条件下的性能表现尚未得到充分研究,且在复杂场景下存在计算复杂度高、实时性不足等问题,提出一种基于有限带宽毫米波通信信号的主动式环境地图构建算法,旨在实现环境地图的实时构建,从而...针对现有环境感知技术在毫米波通信信号带宽受限条件下的性能表现尚未得到充分研究,且在复杂场景下存在计算复杂度高、实时性不足等问题,提出一种基于有限带宽毫米波通信信号的主动式环境地图构建算法,旨在实现环境地图的实时构建,从而提升通信系统的性能.首先,通过在移动端主动式自发自收毫米波通信信号,并获取回波的传播时延和角度信息,结合移动端姿态信息初步感知障碍物的坐标;其次,考虑毫米波通信信号有限带宽对地图分辨率的影响,采用栅格地图算法表征障碍物的空间位置,基于Bresenham算法计算空闲栅格,进而快速准确地构建环境地图,并通过设置不同的地图分辨率,进行了仿真实验,以分析不同地图分辨率条件下的地图构建结果;再次,统计并拟合了感知环境中到达角(Angle Of Arrival,AOA)的分布,以验证冯米塞斯(von Mises)分布的合理性;最后,将结果与基于激光雷达的基准地图进行对比,使用均方根误差(Root Mean Square Error,RMSE)验证精度,使用Jaccard相似度分析验证障碍物形状,并结合代码运行时长评估了算法的效率和系统性能.研究结果表明:所提算法在3GHz带宽和25格/米分辨率下,地图构建达到最优性能,其中RMSE为9.2943,Jaccard系数为0.6254,代码运行时长为14.7746 min,能够满足实时环境感知的需求;与500 MHz带宽和25格/米分辨率下的地图构建结果相比,RMSE、Jaccard系数、代码运行时长分别提升了56.1%、394.4%、70.6%.研究结果可以为未来高动态通信系统发展提供参考.展开更多
Aimed at the problems of a traditional ant colony algorithm,such as the path search direction and field of view,an inability to find the shortest path,a propensity toward deadlock and an unsmooth path,an ant colony al...Aimed at the problems of a traditional ant colony algorithm,such as the path search direction and field of view,an inability to find the shortest path,a propensity toward deadlock and an unsmooth path,an ant colony algorithm for use in a new environment is proposed.First,the feature points of an obstacle are extracted to preprocess the grid map environment,which can avoid entering a trap and solve the deadlock problem.Second,these feature points are used as pathfinding access nodes to reduce the node access,with more moving directions to be selected,and the locations of the feature points to be selected determine the range of the pathfinding field of view.Then,based on the feature points,an unequal distribution of pheromones and a two-way parallel path search are used to improve the construction efficiency of the solution,an improved heuristic function is used to enhance the guiding role of the path search,and the pheromone volatilization coefficient is dynamically adjusted to avoid a premature convergence of the algorithm.Third,a Bezier curve is used to smooth the shortest path obtained.Finally,using grid maps with a different complexity and different scales,a simulation comparing the results of the proposed algorithm with those of traditional and other improved ant colony algorithms verifies its feasibility and superiority.展开更多
基金supported by the grant from the State Programs"Grid Mapping of the Flora of Uzbekistan'during 2020–2024"the grant from the State Programs"Creation of the Digital Platform of the Plant World of Central Uzbekistan"during 2025–2029the State Research Project"Taxonomic Revision of Polymorphic Plant Families of the Flora of Uzbekistan"from the Institute of Botany,Academy of Sciences of the Republic of Uzbekistan (A-FA-2021-427)
文摘In floristic research,the grid mapping method is a crucial and highly effective tool for investigating the flora of specific regions.This methodology aids in the collection of comprehensive data,thereby promoting a thorough understanding of regional plant diversity.This paper presents findings from a grid mapping study conducted in the Surkhan-Sherabad botanical-geographic region(SShBGR),acknowledged as one of the major floristic areas in southwestern Uzbekistan.Using an expansive dataset of 14,317 records comprised of herbarium specimens and field diary entries collected from 1897 to 2023,we evaluated the stages and seasonal dynamics of data accumulation,species richness(SR),and collection density(CD)within 5 km×5 km grid cells.We further examined the taxonomic and life form composition of the region's flora.Our analysis revealed that the grid mapping phase(2021–2023)produced a significantly greater volume of specimens and taxonomic diversity compared with other periods(1897–1940,1941–1993,and 1994–2020).Field research spanned 206 grid cells during 2021–2023,resulting in 11,883 samples,including 6469 herbarium specimens and 5414 field records.Overall,fieldwork covered 251 of the 253 grid cells within the SShBGR.Notably,the highest species diversity was documented in the B198 grid cell,recording 160 species.In terms of collection density,the E198 grid cell produced 475 samples.Overall,we identified 1053 species distributed across 439 genera and 78 families in the SShBGR.The flora of this region aligned significantly with the dominant families commonly found in the Holarctic,highlighting vital ecological connections.Among our findings,the Asteraceae family was the most polymorphic,with 147 species,followed by the continually stable and diverse Poaceae,Fabaceae,Brassicaceae,and Amaranthaceae.Besides,our analysis revealed a predominance of therophyte life forms,which constituted 52%(552 species)of the total flora.The findings underscore the necessity for continual data collection efforts to further enhance our understanding of the biodiversity in the SShBGR.The results of this study demonstrated that the application of grid-based mapping in floristic studies proves to be an effective tool for assessing biodiversity and identifying key taxonomic groups.
基金National Natural Science Foundation of China(No.61373110)the Science-Technology Project of Wuhan,China(No.2014010101010005)
文摘For the mobile robot path planning under the complex environment,ant colony optimization with artificial potential field based on grid map is proposed to avoid traditional ant colony algorithm's poor convergence and local optimum.Firstly,the pheromone updating mechanism of ant colony is designed by a hybrid strategy of global map updating and local grids updating.Then,some angles between the vectors of artificial potential field and the orientations of current grid are introduced to calculate the visibility of eight-neighbor cells of cellular automata,which are adopted as ant colony's inspiring factor to calculate the transition probability based on the pseudo-random transition rule cellular automata.Finally,mobile robot dynamic path planning and the simulation experiments are completed by this algorithm,and the experimental results show that the method is feasible and effective.
文摘This article presents information on the study of the flora of Uzbekistan based on grid system mapping. The urban flora of the city of Bukhara was researched in it. As a result of research, the territory of Bukhara city was divided into 85 indexes based on 1 × 1 km<sup>2</sup> grid mapping system. The diversity and density of species in the indexes are determined. The influence of anthropogenic factors on the diversity of species in the indexes is determined.
文摘针对现有环境感知技术在毫米波通信信号带宽受限条件下的性能表现尚未得到充分研究,且在复杂场景下存在计算复杂度高、实时性不足等问题,提出一种基于有限带宽毫米波通信信号的主动式环境地图构建算法,旨在实现环境地图的实时构建,从而提升通信系统的性能.首先,通过在移动端主动式自发自收毫米波通信信号,并获取回波的传播时延和角度信息,结合移动端姿态信息初步感知障碍物的坐标;其次,考虑毫米波通信信号有限带宽对地图分辨率的影响,采用栅格地图算法表征障碍物的空间位置,基于Bresenham算法计算空闲栅格,进而快速准确地构建环境地图,并通过设置不同的地图分辨率,进行了仿真实验,以分析不同地图分辨率条件下的地图构建结果;再次,统计并拟合了感知环境中到达角(Angle Of Arrival,AOA)的分布,以验证冯米塞斯(von Mises)分布的合理性;最后,将结果与基于激光雷达的基准地图进行对比,使用均方根误差(Root Mean Square Error,RMSE)验证精度,使用Jaccard相似度分析验证障碍物形状,并结合代码运行时长评估了算法的效率和系统性能.研究结果表明:所提算法在3GHz带宽和25格/米分辨率下,地图构建达到最优性能,其中RMSE为9.2943,Jaccard系数为0.6254,代码运行时长为14.7746 min,能够满足实时环境感知的需求;与500 MHz带宽和25格/米分辨率下的地图构建结果相比,RMSE、Jaccard系数、代码运行时长分别提升了56.1%、394.4%、70.6%.研究结果可以为未来高动态通信系统发展提供参考.
基金the National Natural Science Founda-tion(Nos.62063019 and 61763026)the Gansu Nat-ural Science Foundation Project(No.20JR10RA152)the Gansu Provincial Department of Educa-tion:Excellent Graduate“Innovation Star”Project(No.2021CXZX-507)。
文摘Aimed at the problems of a traditional ant colony algorithm,such as the path search direction and field of view,an inability to find the shortest path,a propensity toward deadlock and an unsmooth path,an ant colony algorithm for use in a new environment is proposed.First,the feature points of an obstacle are extracted to preprocess the grid map environment,which can avoid entering a trap and solve the deadlock problem.Second,these feature points are used as pathfinding access nodes to reduce the node access,with more moving directions to be selected,and the locations of the feature points to be selected determine the range of the pathfinding field of view.Then,based on the feature points,an unequal distribution of pheromones and a two-way parallel path search are used to improve the construction efficiency of the solution,an improved heuristic function is used to enhance the guiding role of the path search,and the pheromone volatilization coefficient is dynamically adjusted to avoid a premature convergence of the algorithm.Third,a Bezier curve is used to smooth the shortest path obtained.Finally,using grid maps with a different complexity and different scales,a simulation comparing the results of the proposed algorithm with those of traditional and other improved ant colony algorithms verifies its feasibility and superiority.
