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Environmental DNA assessment of fish diversity, distribution and niche characteristics in Zhutuo spawning ground in the upper reaches of the Yangtze River
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作者 LU Jia WANG Li +3 位作者 LI Ruijiao YANG Jin ZHANG Peng YANG Shengfa 《水利水电技术(中英文)》 北大核心 2025年第S1期454-467,共14页
[Objective]Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in t... [Objective]Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in the Upper Yangtze River.This study initiated continuous monitoring of natural spawning habitats from February 2022 to assess these ecological changes.[Methods]Environmental DNA(eDNA)metabarcoding was employed to analyze fish species composition,biodiversity patterns,and niche parameters of dominant species.Water sampling followed the CEN/TS 19461 standard across five monitoring transects(ZT1-ZT5).[Results]The eDNA analysis detected 45 species of fish belonging to 38 genera,13 families,and 3 orders were detected through environmental DNA(eDNA)in this survey,including 10 species endemic to the upper reaches of the Yangtze River,such as Procypris rabaudi and Myxocyprinus asiaticus.The fish community was mainly composed of bottom-dwelling,settling ovum-producing,omnivorous fish.The variation ranges of the Chao1 index,ACE index,Shannon index,and Simpson index are 736~996,719~965,1.58~3.23,and 0.83~0.99,respectively,indicating that fish species in spawning sites are abundant and community distribution uniformity is high.All indexes are highest at ZT1 monitoring points.Cluster analysis showed that,at a certain similarity level,fish community types in spawning sites could be basically divided into two groups:ZT1,ZT3,and ZT5 clustered together,and ZT2 and ZT4 clustered together,indicating similar fish community habitats.There are 9 dominant fish species in typical deep pool habitats in the reserve,with niche widths(Bi)ranging from 1.13 to 3.87.The dominant fish species are broad and medium niche fish,such as Cyprinus carpio and Hemiculter tchangi,with the niche overlap index(Oik)of some dominant fish species reaching more than 0.95.This indicates fierce competition for resources among the fish in this spawning ground.[Conclusion]The Zhutuo spawning ground demonstrates high species richness with homogeneous community structure and intense resource competition.This study establishes an eDNA-based monitoring framework that enhances conventional survey method,providing critical baseline data for adaptive management under the fishing moratorium regime. 展开更多
关键词 eDNA metabarcoding fishes endemic to the upper reaches of the Yangtze River spawning ground fish diversity niche characteristics
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Evolution mechanism of unmanned cluster cooperation oriented toward strategy selection diversity
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作者 XIE Zhenhai YU Minggang +4 位作者 HE Ming CHEN Guoyou ZHAI Zheng WANG Ziyu LIU Lu 《Journal of Systems Engineering and Electronics》 2025年第2期462-482,共21页
When performing tasks,unmanned clusters often face a variety of strategy choices.One of the key issues in unmanned cluster tasks is the method through which to design autonomous collaboration and cooperative evolution... When performing tasks,unmanned clusters often face a variety of strategy choices.One of the key issues in unmanned cluster tasks is the method through which to design autonomous collaboration and cooperative evolution mechanisms that allow for unmanned clusters to maximize their overall task effective-ness under the condition of strategic diversity.This paper ana-lyzes these task requirements from three perspectives:the diver-sity of the decision space,information network construction,and the autonomous collaboration mechanism.Then,this paper pro-poses a method for solving the problem of strategy selection diversity under two network structures.Next,this paper presents a Moran-rule-based evolution dynamics model for unmanned cluster strategies and a vision-driven-mechanism-based evolu-tion dynamics model for unmanned cluster strategy in the con-text of strategy selection diversity according to various unmanned cluster application scenarios.Finally,this paper pro-vides a simulation analysis of the effects of relevant parameters such as the payoff factor and cluster size on cooperative evolu-tion in autonomous cluster collaboration for the two types of models.On this basis,this paper presents advice for effectively addressing diverse choices in unmanned cluster tasks,thereby providing decision support for practical applications of unmanned cluster tasks. 展开更多
关键词 unmanned cluster strategy diversity dynamic model cooperative evolution
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基于Unity 3D的灭火器虚拟消防模拟
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作者 薛锦云 周智鹏 +3 位作者 薛慧琦 易心武 李志辉 刘智高 《计算机工程与科学》 北大核心 2025年第6期1090-1096,共7页
传统的消防训练需要消防员及相关人员面对大火进行实操,这不仅需要场地、资金的支持,还可能会有人员伤亡的风险。随着虚拟现实的发展,如何使用其模拟真实环境的能力让用户完成目标任务已成为当今研究的热点。利用Unity 3D强大的三维渲... 传统的消防训练需要消防员及相关人员面对大火进行实操,这不仅需要场地、资金的支持,还可能会有人员伤亡的风险。随着虚拟现实的发展,如何使用其模拟真实环境的能力让用户完成目标任务已成为当今研究的热点。利用Unity 3D强大的三维渲染能力和灵活的脚本系统,结合虚拟现实的粒子系统对火焰和灭火器喷雾进行模拟,能真实还原消防人员的训练环境。为了模拟的真实度,采用动力学原理模拟灭火器喷雾前期的运动轨迹,提出以高斯扩散模型对喷雾后期在空气中的弥漫进行分析。实验结果证明动力学原理和高斯扩散模型能成功模拟出灭火器喷雾的动态变化过程。同时,利用粒子间的碰撞实现了灭火器的灭火过程,使用户能够直观地感受到灭火器喷雾对火焰的影响。 展开更多
关键词 unity 3D 虚拟现实 粒子系统 高斯扩散模型 消防
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基于Unity的生产线可视化智能监控系统 被引量:2
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作者 于盼磊 高玉飞 +2 位作者 袁徽涌 赵晓龙 马嵩华 《组合机床与自动化加工技术》 北大核心 2025年第1期1-4,9,共5页
针对自动化生产线存在的高效智能监控难题,设计了一种基于Unity的生产线可视化监控系统架构。对虚拟场景搭建、模型随动控制、虚拟生产线可视化等技术进行了论述,提出了一种基于权重的优先通信策略;对设备故障、转运干涉/卡顿、异物进... 针对自动化生产线存在的高效智能监控难题,设计了一种基于Unity的生产线可视化监控系统架构。对虚拟场景搭建、模型随动控制、虚拟生产线可视化等技术进行了论述,提出了一种基于权重的优先通信策略;对设备故障、转运干涉/卡顿、异物进入等异常状况,基于多源数据的差异进行分析和判断,形成了多源数据驱动下的智能监控方法。对于离散制造生产线上设备众多、数据异构带来的通信延迟问题,提出了复杂生产线的通信优先级和数据同步性,形成一套可行的生产线可视化智能监控解决方案。 展开更多
关键词 生产线监控 unity3D 三维可视化 实时驱动 数据采集
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Characteristics of soil microbial community functional and structure diversity with coverage of Solidago Canadensis L 被引量:13
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作者 廖敏 谢晓梅 +2 位作者 彭英 柴娟娟 陈娜 《Journal of Central South University》 SCIE EI CAS 2013年第3期749-756,共8页
The relationship between Solidago canadensis L. invasion and soil microbial community diversity including functional and structure diversities was studied across the invasive gradients varying from 0 to 40%, 80%, and ... The relationship between Solidago canadensis L. invasion and soil microbial community diversity including functional and structure diversities was studied across the invasive gradients varying from 0 to 40%, 80%, and 100% coverage of Solidago canadensis L. using sole carbon source utilization profiles analyses, principle component analysis (PCA) and phospholipid fatty acids (PLFA) profiles analyses. The results show the characteristics of soil microbial community functional and structure diversity in invaded soils strongly changed by Solidago canadensis L. invasion. Solidago canadensis L. invasion tended to result in higher substrate richness, and functional diversity. As compared to the native and ecotones, average utilization of specific substrate guilds of soil microbe was the highest in Solidago canadensis L. monoculture. Soil microbial functional diversity in Solidago canadensis L. monoculture was distinctly separated from the native area and the ecotones. Aerobic bacteria, fungi and actinomycetes population significantly increased but anaerobic bacteria decreased in the soil with Solidago canadensis L. monoculture. The ratio of cyl9:0 to 18:1 co7 gradually declined but mono/sat and fung/bact PLFAs increased when Solidago canadensis L. became more dominant. The microbial community composition clearly separated the native soil from the invaded soils by PCA analysis, especially 18: lco7c, 16: lco7t, 16: lco5c and 18:2co6, 9 were present in higher concentrations for exotic soil. In conclusion, Solidago canadensis L. invasion could create better soil conditions by improving soil microbial community structure and functional diversity, which in turn was more conducive to the growth ofSolidago canadensis L. 展开更多
关键词 sole carbon source utilization phospholipid fatty acids structure diversity functional diversity Solidago canadensis L.
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Influence of functionalized graphene on the bacterial and fungal diversity of Vicia faba rhizosphere soil
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作者 CHEN Zhi-wen REN Jing +7 位作者 QIAO Jun ZHAO Jian-guo LI Jing-wei LIU Ze-hui LI Wei-jia XING Bao-yan ZHANG Jin NIE Hui 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第6期1227-1242,共16页
The effect of functionalized graphene on the growth and development of Vicia faba L.was investigated by analyzing its impact on the composition and diversity of the microbial community in rhizosphere peat soil.Seedlin... The effect of functionalized graphene on the growth and development of Vicia faba L.was investigated by analyzing its impact on the composition and diversity of the microbial community in rhizosphere peat soil.Seedlings of V.faba planted in this peat soil were treated with either distilled water(CK)or 25 mg·L^(−1)(G25)of functionalized graphene solution.Results showed that the height and root length of V.faba seedlings in the G25 group were significantly larger than those in CK group.The microbial com-munity was analyzed by amplifying and sequencing the 16S rRNA gene V_(3)-V_(4) region of bacteria and internal transcribed spacer re-gion of fungi in rhizosphere soil using Illumina MiSeq technology.Alpha and beta diversity analysis indicated that functionalized graphene increased the richness and diversity of bacteria and fungi in the V.faba rhizosphere peat soil.The abundances of three ni-trogen cycling-related bacteria,Hydrogenophaga,Sphingomonas and Nitrosomonadaceae,were also altered after treatment with the functionalized graphene.The relative abundance of Basilicum,related to soil phosphorus solubilization,decreased in the fungal com-munity,while the relative abundance of Clonostachys and Dimorphospora,which exhibited strong biological control over numerous fungal plant pathogens,nematodes and insects,increased in the soil after functionalized graphene treatment.Redundancy analysis re-vealed that the potential of hydrogen(pH),organic matter,and total phosphorus contributed the most to the changes in bacterial and fungal community composition in the rhizosphere soil.Overall,our findings suggested that the addition of functionalized graphene altered the relative abundances of nitrogen and phosphorus cycling-related microorganisms in peat soil,promoting changes in the physicochemical properties of the soil and ultimately leading to the improved growth of V.faba plants. 展开更多
关键词 Functionalized graphene Vicia faba L. Plant growth Rhizosphere soil Microbial diversity
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基于Unity3D和VR的无人机虚拟飞行系统
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作者 张普丞 张锐 袁得春 《传感器与微系统》 北大核心 2025年第7期85-88,共4页
基于Unity3D引擎,构建了1︰1高精度的无人机飞行场景及四旋翼无人机模型。通过设计PID控制器,精准调控无人机的姿态--包括沿水平轴的俯仰运动、绕纵轴的滚转动作,以及绕垂直轴的偏航摆动。开发过程中,对控制参数进行精细化调校,确保模... 基于Unity3D引擎,构建了1︰1高精度的无人机飞行场景及四旋翼无人机模型。通过设计PID控制器,精准调控无人机的姿态--包括沿水平轴的俯仰运动、绕纵轴的滚转动作,以及绕垂直轴的偏航摆动。开发过程中,对控制参数进行精细化调校,确保模拟场景中无人机的响应机制与行为表现高度逼近真实无人机的运行逻辑。最终将模拟系统适配至虚拟现实(VR)平台,使用户在沉浸式环境中与系统交互,获得近乎等同于操控真实无人机的体验,实现虚拟操作与现实感知的深度融合。 展开更多
关键词 unity3D 虚拟现实技术 无人机飞手考级 虚拟仿真 四旋翼无人机 无人机飞行
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Molecular Diversity of Marine Phytoplankton Communities Based on Key Functional Genes
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作者 Punyasloke Bhadury Bess B.Ward 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期249-249,共1页
The phylogeny and diversity of two key functional genes were investigated as the basis for improved understanding of the community structure of natural phytoplankton assemblages in marine environments. New partial NR(... The phylogeny and diversity of two key functional genes were investigated as the basis for improved understanding of the community structure of natural phytoplankton assemblages in marine environments. New partial NR(encoding eukaryotic assimilatory nitrate reductase) and rbcL(encoding the large subunit of the ribulose-1,5-bisphosphate carboxylase/oxygenase) sequences from ten cultured phytoplankton strains are reported.Phytoplankton community com- 展开更多
关键词 assimilatory NITRATE REDUCTASE community composition MARINE PHYTOPLANKTON RBCL diversity
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Key fungal communities related to alleviating replanting stress of Lanzhou lily under silicon fertilizer and microbial agents application
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作者 WANG Yi-qin YU Yan-lin +5 位作者 YANG Hong-yu LI Hui HOU Lei MAN Hua-li HAN Jia SHI Gui-ying 《植物营养与肥料学报》 北大核心 2025年第2期395-406,共12页
【Objectives】Si and microbial application could relieve the crop replanting problems(CRPs).We further studied the change of key microorganisms that are related to the beneficial effects,aiming at provide reference fo... 【Objectives】Si and microbial application could relieve the crop replanting problems(CRPs).We further studied the change of key microorganisms that are related to the beneficial effects,aiming at provide reference for the manufacture and application of both microbial agents and Si fertilizer in food lily production.【Methods】A field experiment was conducted over a three-year period,from March 2019 to March 2022.The experimental field had been continuously cultivated with lily for 9 years.Three treatments were established:silicon fertilizer(SF),microbial agents(“Special 8^(TM)”,MF),and combined application of silicon fertilizer and microbial agents(SMF).A control group with blank soil(CK)was also included.At seedling stage of Lanzhou lilies in 2020 and 2021,the shoot and bulb dry weight,and the plant height and stem diameter of Lanzhou lilies were investigated for calculation of seedling index.In July 2020,20 plants were selected in each plot,and root zone soils were sampled at a depth of 20 cm,10 cm away from the roots,and then mixed to form a composite sample.The soil available Si and organic matter content were analyzed,and the fungal community structure and some specific microbial groups in soils were determined with high-throughput sequencing of ITS.【Results】All the three treatments significantly enhanced the lily plant growth and the seedling index,compared to CK.Besides,SF and MF treatments increased the relative abundances(RA)and diversity of fungal communities,and altered the community structures.The RA of some specific groups were found to be significantly correlated with the seedling index and/or soil available Si.Of them,the RA of the genera Fusarium,Dactylonectria,Humicola,Stilbella,and the species Humicola_grisea showed a positive correlation,while that of the genera Mortierella,Stilbella,Holtermanniella,and the species Mortierella_fatshederae showed a negative correlation with seedling index.The genera Fusarium,Stilbella,the species Humicola_grisea,and Dactylonectria_estremocensis showed a positive correlation,while the genura Stilbella,and the species Mortierella fatshederae showed a negative correlation with available Si content.In the co-occurence network of top twenty fungal genera and top sixteen bacterial genera(RA>0.2%),Holtermanniella was the only genus that interacted with the bacteria and negatively correlated with bacterial genus Blastococcus.Holtermanniella was also the most densely connected genera,followed by the genus Fusarium,Didymella and Humicola.In addition,the genus Holtermanniella was the key species connecting fungal and bacterial community in soil.Fungal functional prediction revealed that SF,MF and SMF treatments decreased plant pathogens guilds and increased the beneficial guilds Ectomycorrhizal,plant saprophyte,leaf saprophyte,and arbuscular mycorrhizal compared to CK.【Conclusions】Combined application of silicon fertilizer and microbial agents can alleviate continuous replanting problems of Lanzhou lilies through restoring the fungal community diversity,and promoting plant residue depredation,thus reducing soil born disease incidence.The beneficial genus Humicola and its one species H.grisea acts as bioconversion,and the genus Acremonium acts as plant pathogen inhibitor. 展开更多
关键词 Lanzhou lily soil fungi diversity pathotroph saprophyte silicon fertilization microbial agent
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基于Unity3D虚拟平台对农机装备作业行为的研究
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作者 张鲜玉 《农机使用与维修》 2025年第6期14-17,共4页
为实现农机装备的智能化,提升农业机械化水平。通过仿真试验,构建基于Unity3D的农机装备作业仿真平台,并对其整体架构进行设计。经仿真研究,作物茎秆各分段在风力影响下均存在方向偏移,茎秆越高,偏移位移和速度均越大;作物发生偏移时的... 为实现农机装备的智能化,提升农业机械化水平。通过仿真试验,构建基于Unity3D的农机装备作业仿真平台,并对其整体架构进行设计。经仿真研究,作物茎秆各分段在风力影响下均存在方向偏移,茎秆越高,偏移位移和速度均越大;作物发生偏移时的瞬时速度在整个偏移过程中类似于正弦曲线变化。通过对作物的收获状态观察,该仿真平台符合作业仿真要求,同时交互作物对象形变真实。随行进速度的增大,欠收率快速下降,且作物密度越大,欠收率下降明显减缓,表明该农机装备作业仿真平台可应用于收获作业行为研究。 展开更多
关键词 农机装备 unity3D 欠收率 作物密度
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基于Unity3D的矿井火灾监测与防治虚拟仿真试验系统 被引量:2
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作者 裴晓东 姚志远 +3 位作者 王亮 邵昊 王凯 吴征艳 《中国安全科学学报》 CAS CSCD 北大核心 2024年第3期109-116,共8页
为更好地开展矿业安全类专业试验实践教学和培训,培养安全应急一流复合型拔尖人才,设计一种基于Unity3D的矿井火灾监测与防治虚拟仿真试验教学系统。首先,采用3ds Max建立仿真模型,构建矿井火灾监测防治试验系统总体框架;其次,开展外因... 为更好地开展矿业安全类专业试验实践教学和培训,培养安全应急一流复合型拔尖人才,设计一种基于Unity3D的矿井火灾监测与防治虚拟仿真试验教学系统。首先,采用3ds Max建立仿真模型,构建矿井火灾监测防治试验系统总体框架;其次,开展外因火灾监测与远程自动控制救灾风门应急处置、内因火灾监测与温控胞衣阻化剂防灭火应急防控等人机交互试验实训;最后,建立综合评测的试验评价体系用于考核评估。结果表明:该试验系统具备虚拟现实沉浸性、交互性、构想性的技术特点,利于打造井下三维虚拟仿真场景,逼真展示矿井火灾演变过程;在试验与实训方面,可以突破传统模式在时间、空间、安全、资源等方面的限制,提供自主学习与多元评价方式。 展开更多
关键词 unity3D 矿井火灾 监测与防治 虚拟仿真 试验系统 应急处置
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融合Unity3D的缆索起重机安全运行数字孪生模型构建方法 被引量:4
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作者 陈述 鲁世立 +3 位作者 王建平 陈云 张光飞 李智 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第1期154-159,共6页
为降低缆索起重机(下文简称为缆机)运行的安全风险,分析缆机运行流程,提取缆机安全运行知识语义,通过物联网技术获取实时数据,利用3DS Max软件构建大坝缆机运行初始场景,实现孪生模型三维可视化,将模型导入Unity3D引擎,使用高清渲染管... 为降低缆索起重机(下文简称为缆机)运行的安全风险,分析缆机运行流程,提取缆机安全运行知识语义,通过物联网技术获取实时数据,利用3DS Max软件构建大坝缆机运行初始场景,实现孪生模型三维可视化,将模型导入Unity3D引擎,使用高清渲染管线对模型进行渲染,改善视觉效果,编写C#脚本对缆机运行全过程进行安全模拟仿真。研究结果表明:应用本文所构建的缆机安全运行数字孪生模型监测隐患与故障,综合准确率达到96.7%,可有效实现缆机运行过程的安全监控、参数化控制以及可视化展示。研究结果可为缆机施工过程的安全控制提供技术支持。 展开更多
关键词 unity3D 缆索起重机 数字孪生 物联网 实时监测 安全管理工程
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基于Unity3D的工作面液压支架群组空间支护姿态数字孪生重构方法 被引量:1
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作者 曾庆良 班新亮 +2 位作者 孟昭胜 万丽荣 雷小万 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第11期74-88,共15页
煤炭是我国的关键能源,保障煤炭资源安全高效开采对我国具有重要战略意义。我国煤炭资源以井工开采为主,生产环境较恶劣且工人劳动强度大,智能化开采因其减人提效理念内涵成为我国煤炭行业高质量发展的必由之路。液压支架是井工开采关... 煤炭是我国的关键能源,保障煤炭资源安全高效开采对我国具有重要战略意义。我国煤炭资源以井工开采为主,生产环境较恶劣且工人劳动强度大,智能化开采因其减人提效理念内涵成为我国煤炭行业高质量发展的必由之路。液压支架是井工开采关键支护装备,其支护性能同时受本体支护姿态及群组关联姿态影响。受井下复杂开采条件影响,液压支架支护姿态信息获取困难,因此如何智能精准地感知液压支架群组空间支护姿态是制约智能化建设的重大难题之一。为精准描述工作面液压支架群组空间支护姿态,首先分析了液压支架群组空间连接关系,建立了基于多杆双驱的液压支架自姿态感知模型和基于空间多线协同定姿的架群姿态感知模型,分析了不同求解策略对自姿态模型解算性能影响。随后借助三维互动平台Unity3D搭建了工作面液压支架群组数字孪生环境,开发了基于工作面真实场景数据驱动的可视化系统。最后,依托山东某矿对所述方法开展了工程验证,结果表明提出的液压支架群组空间支护姿态孪生重构方法能精确映射实际液压支架群组真实空间支护位态,解决了液压支架支护本体支护姿态信息易受现场振动干扰和支架群组关联姿态信息缺失难题。论文所提方法为工作面多智能体运行行为全场景虚拟再现及工作面智能化建设提供思路借鉴。 展开更多
关键词 液压支架 数字孪生 自姿态 群姿态 unity3D
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基于Unity 3D的农业机械虚拟拆装驾驶仿真平台开发 被引量:1
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作者 梁方 徐菲 +2 位作者 杨坤 廖庆喜 廖宜涛 《农业工程》 2024年第11期23-29,共7页
为实现农业机械学课程农业机械结构虚拟拆装与驾驶教学,应用Solidworks和3Ds Max创建与农业机械学课程教学内容匹配的农业机械三维模型,基于Unity 3D、结合X Dreamer可视化编程与C#脚本编程,开发人机实时交互农业机械拆装驾驶虚拟仿真... 为实现农业机械学课程农业机械结构虚拟拆装与驾驶教学,应用Solidworks和3Ds Max创建与农业机械学课程教学内容匹配的农业机械三维模型,基于Unity 3D、结合X Dreamer可视化编程与C#脚本编程,开发人机实时交互农业机械拆装驾驶虚拟仿真开源平台。构建了平台总体框架与界面层级,阐释了平台操作页面、虚拟拆装模块、虚拟驾驶模块的设计流程与主要程序代码。用户可以在该仿真平台上进行虚拟拆装、虚拟驾驶和场景漫游,直观深入地掌握农业机械的复杂结构和运行原理等核心知识点,实现理论知识与实践知识的高度融合。该研究为虚拟拆装与驾驶教学仿真平台的开发提供参考。 展开更多
关键词 unity 3D 三维建模 虚拟拆装 虚拟驾驶 农业机械学
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基于Unity 3D的电梯事故应急演练系统设计 被引量:2
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作者 任重义 石梓迅 +3 位作者 马立新 姚国龙 张明明 于菲 《中国工程机械学报》 北大核心 2024年第4期474-478,共5页
根据传统电梯事故应急演练存在安全隐患、花费开销大、受时空局限等特点,为了降低电梯事故发生率,针对电梯事故,提出了基于Unity 3D电梯事故应急演练系统设计方案,进行电梯事故应急演练系统整体功能模块设计。利用3DS Max建立三维模型,... 根据传统电梯事故应急演练存在安全隐患、花费开销大、受时空局限等特点,为了降低电梯事故发生率,针对电梯事故,提出了基于Unity 3D电梯事故应急演练系统设计方案,进行电梯事故应急演练系统整体功能模块设计。利用3DS Max建立三维模型,并对模型做出模型减面、材质调配、贴图渲染等优化操作。模型被导入Unity 3D后,进行虚拟场景搭建、图形用户界面(GUI)设计、脚本编辑。针对自动扶梯的挤压事故,介绍系统的演练流程和演练效果。实现应急演练系统总体功能,满足了演练人员的基本培训需求。 展开更多
关键词 unity 3D 电梯事故 应急演练 培训系统
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Large scale classification with local diversity AdaBoost SVM algorithm 被引量:5
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作者 Chang Tiantian Liu Hongwei Zhou Shuisheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第6期1344-1350,共7页
Local diversity AdaBoost support vector machine(LDAB-SVM) is proposed for large scale dataset classification problems.The training dataset is split into several blocks firstly, and some models based on these dataset... Local diversity AdaBoost support vector machine(LDAB-SVM) is proposed for large scale dataset classification problems.The training dataset is split into several blocks firstly, and some models based on these dataset blocks are built.In order to obtain a better performance, AdaBoost is used in each model building.In the boosting iteration step, the component learners which have higher diversity and accuracy are collected via the kernel parameters adjusting.Then the local models via voting method are integrated.The experimental study shows that LDAB-SVM can deal with large scale dataset efficiently without reducing the performance of the classifier. 展开更多
关键词 ensemble learning large scale data support vector machine ADABOOST diversity local.
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Diversity,Systematic and Evolution of Fossil Osmundaceous Ferns in China 被引量:2
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作者 Ning Tian,Yongdong Wang,Zikun Jiang Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期256-257,共2页
The family Osmundaceae receives much concern of palaeobotanists for its peculiar sporangia and phylogenetic relationship.Abundant osmundaceous fossils have been reported in China.So far,about 34 species ascribed to se... The family Osmundaceae receives much concern of palaeobotanists for its peculiar sporangia and phylogenetic relationship.Abundant osmundaceous fossils have been reported in China.So far,about 34 species ascribed to seven genera of Osmundaceae have been documented except for three morphogenera. 展开更多
关键词 OSMUNDACEAE diversity systematic EVOLUTION ecological IMPLICATION China
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The Genetic Diversity Study of Wild Wusuli Raccoon Dog From Nenjiang District 被引量:3
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作者 YANG Chunshan BAI Xiujuan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第3期20-24,共5页
The ISSR method was developed to analyze the genetic diversity of 20 wild Wusuli raccoon dog from Nenjiang district. The results showed that there were significant genetic diversity and high polymorphism among individ... The ISSR method was developed to analyze the genetic diversity of 20 wild Wusuli raccoon dog from Nenjiang district. The results showed that there were significant genetic diversity and high polymorphism among individuals of the wild Wusuli raccoon dog. A total of 41 DNA bands were amplified by 9 primers, and 37 of them were polymorphism, the proportion of polymorphism was 90.24%, 2-8 polymorphism bands could be amplified by each primer, and 4.56 on average, the length of the product was 200-2 000 bp. 展开更多
关键词 Wusuli raccoon dog ISSR genetic diversity
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Genetic Diversity Analysis Among Populations of Mink from China by Inter-simple Sequence Repeat(ISSR) Markers 被引量:2
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作者 Yang Hong-yan Fu Jing +2 位作者 Ning Fang-yong Du Zhi-heng Bai Xiu-juan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2013年第3期47-54,共8页
Inter-simple Sequence Repeat (ISSR) analysis was applied to assess the genetic diversity within and among five populations of mink from Liaoning Province. A total of 20 primers were screened, five selected primers p... Inter-simple Sequence Repeat (ISSR) analysis was applied to assess the genetic diversity within and among five populations of mink from Liaoning Province. A total of 20 primers were screened, five selected primers produced 35 discernible bands, with 30 (85.71%) being polymorphic, indicating high genetic diversity at the species level. The highest genetic diversity was observed in the brown mink population, whereas the lowest diversity was found in the standard-pitchy mink population. Based on genetic distance (1972), a dendrogram was constructed by using UPGMA algorithm, and five populations were divided into two major groups. Group I consisted of only the standard-pitchy mink population, and Group II included other four populations, in Group II, sapphire mink was close to brown mink population. The results of genetic differentiation indicated that the genetic differentiation degree between populations was lower and the genetic variation primarily came from within populations. This paper showed that ISSR technique was a reliable tool that could be used to study genetic diversity in the mink. 展开更多
关键词 MINK ISSR genetic diversity
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Identification and Genetic Diversity Analysis of Chinese Mitten Crab(Eriocheir sinensis) in the Liao River Area 被引量:3
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作者 Wang Shi-hui Li Chi-tao +4 位作者 Shang Mei Jia Zhi-ying Hu Xue-song Ge Yan-long Shi Lian-yu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2018年第2期43-53,共11页
Chinese mitten crab (Eriocheir sinensis) is an indigenous and ecologically and economically important species in the Liao River area, but its identification and genetic diversity remain poorly understood. To evaluat... Chinese mitten crab (Eriocheir sinensis) is an indigenous and ecologically and economically important species in the Liao River area, but its identification and genetic diversity remain poorly understood. To evaluate the germplasm resources of this species, samples were collected from these locations: four sub-populations from the Liao River area and one population from the Yangtze River area; one primer was used to distinguish between the Liao River and the Yangtze River crabs. Thirteen loci were used for crab genetic diversity analysis, and basic statistics showed that the collecting samples were purebred in the Liao River area. The average observed heterozygosity (H0) of the Liao River population was 0.5931, and the expected heterozygosity (He) was 0.8064. The polymorphism information content (PIC) was 0.7753, which showed that the Liao River population had high genetic diversity. The genetic differentiation index (FST) averaged 0.0342, meaning a low degree of differentiation; cluster analysis indicated that Hujia (HJ), Xinli (XL) and Chenjia (CJ) sub-populations were allocated to the same cluster, while Baqiangzi (BQZ) sub-population was isolated. In summary, these data demonstrated that the crabs in the Liao River had high genetic diversity, but low genetic differentiation. Thus, the Liao River population had the potential for breeding selection. Furthermore, this study also provided valuable genetic information for the conservation of Chinese mitten crab. 展开更多
关键词 Chinese mitten crab genetic diversity MICROSATELLITE the Liao River population
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