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Seedling dynamics differ between canopy species and understory species in a tropical seasonal rainforest,SW China

Plant Diversity 2024年第5期46卷 671-677页

作者： Libing Pan Xiaoyang Song wenfu zhang Jie Yang Min Cao CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMengla 666303YunnanChina College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

We used 11 years of census data from 450 seedling quadrats established in a 20-ha forest dynamics plot to study seedling dynamics in tree species of a tropical seasonal rainforest in Xishuangbanna,southwestern *** found that overall seedling recruitment rate and relative growth rate were higher in the rainy season than in the dry *** the recruitment rate of seedlings from canopy tree species(two species)and the relative growth rate of seedlings from understory species(nine species)were higher in the rainy season than in the dry ***,in the rainy season,the recruitment rate of seedlings was higher for canopy tree species than for understory tree *** addition,relative growth rate of seedlings was higher in the canopy species than in understory seedlings in the dry *** also observed that,in both rainy and dry seasons,mortality rate of seedlings was higher for canopy species than for understory ***,canopy tree species appear to have evolved a flexible strategy to adapt to the seasonal changes of a monsoon *** contrast,understory tree species seem to have adopted a conservative ***,these species mainly release seedlings in the rainy season and maintain relatively stable populations with a lower mortality rate and recruitment rate in both dry and rainy *** study suggests that canopy and understory seedling populations growing in forest understory may respond to future climate change scenarios with distinct regeneration strategies.

关键词： Tropical forest Tree seedling Seasonality Recruitment Mortality Relative growth rate

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Spectral-interferometry-based diff-iteration for high-precision micro-dispersion measurement

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Photonics Research 2024年第6期12卷 1362-1370页

作者： WEI DU JINGSHENG HUANG YANG WANG MAOZHONG ZHAO JUAN LI JUNTAO HE JINDONG WANG wenfu zhang TAO ZHU Key Laboratory of Optoelectronic Technology&System(Ministry of Education) Chongqing UniversityChongqing 400044China State Key Laboratory of Transient Optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China

Precise measurement of micro-dispersion for optical devices(optical fiber,lenses,etc.)holds paramount significance across domains such as optical fiber communication and dispersion interference ***,due to its complex system,complicated process,and low reliability,the traditional dispersion measurement methods(interference,phase shift,or time delay methods)are not suitable for the accurate measurement of micro-dispersion in a wide spectral ***,we propose a spectral-interferometry-based diff-iteration(SiDi)method for achieving accurate wide-band micro-dispersion *** an optical frequency comb,based on the phase demodulation of the dispersion interference spectrum,we employ the carefully designed SiDi method to solve the dispersion curve at any position and any *** approach is proficient in precisely measuring micro-dispersion across a broadband spectrum,without the need for cumbersome wavelength scanning processes or reliance on complex high-repetition-rate combs,while enabling adjustable *** efficacy of the proposed method is validated through simulations and *** employed a chip-scaled soliton microcomb(SMC)to compute the dispersion curves of a 14 m single-mode fiber(SMF)and a 0.05 m *** to a laser interferometer or the theoretical value given by manufacturers,the average relative error of refractive index measurement for single-mode fiber(SMF)reaches 2.8×10^(-6) and for glass reaches 3.8×10^(-6).The approach ensures high precision,while maintaining a simple system structure,with realizing adjustable resolution,thereby propelling the practical implementation of precise measurement and control-dispersion.

关键词： interferometer dispersion iteration

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Scalable parallel ultrafast optical random bit generation based on a single chaotic microcomb

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Light(Science & Applications) 2024年第4期13卷 637-644页

作者： Pu Li Qizhi Li Wenye Tang Weiqiang Wang wenfu zhang Brent ELittle Sai Tek Chu KAlan Shore Yuwen Qin Yuncai Wang Institute of Advanced Photonics Technology School of Information EngineeringGuangdong University of TechnologyGuangzhou 51006China. Key Laboratory of Photonic Technology for Integrated Sensing and Communication Ministry of Education of ChinaGuangdong University of TechnologyGuangzhou 51006China. Guangdong Provincial Key Laboratory of Information Photonics Technology Guangdong University of TechnologyGuangzhou 51006China. Key Laboratory of Advanced Transducers andIntelligent Control System Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China. State Key Laboratory of Transient Optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China. Department of Physics and Materials Science City University of Hong KongHong KongChina. School of Electronic Engineering Bangor UniversityBangorWales LL571UTUK

Random bit generators are critical for information security,cryptography,stochastic modeling,and *** and scalability are key challenges faced by current physical random bit ***,we propose a massively parallel scheme for ultrafast random bit generation towards rates of order 100 terabit per second based on a single micro-ring resonator.A modulation-instability-driven chaotic comb in a micro-ring resonator enables the simultaneous generation of hundreds of independent and unbiased random bit streams.A proof-of-concept experiment demonstrates that using our method,random bit streams beyond 2 terabit per second can be successfully generated with only 7 comb *** bit rate can be easily enhanced by further increasing the number of comb lines *** approach provides a chip-scale solution to random bit generation for secure communication and high-performance computation,and offers superhigh speed and large scalability.

关键词： resonator random chaotic

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Overstory functional groups indicate the legacy of land use in a secondary tropical forest in southwestern China

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Journal of Forestry Research 2024年第5期35卷 91-105页

作者： Yun Deng wenfu zhang Min Cao Jinlong Dong Hui Chen Xiaobao Deng Jiajia Liu Xiaoyang Song Shangwen Xia Liqing Sha Shengdong Yuan Luxiang Lin CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303People’s Republic of China Center for Plant Ecology Core Botanical GardensChinese Academy of SciencesMengla 666303People’s Republic of China National Forest Ecosystem Research Station at Xishuangbanna Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303People’s Republic of China Department of Life Sciences Fudan UniversityShanghai 570228People’s Republic of China Department of Life Sciences University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the ***,the impacts of historical disturbance on tropical forest overstory recovery are unclear due to a lack of disturbance data,and previous studies have focused on understory *** this study,the purpose was to deter-mine the influence of historical disturbance on the diver-sity,composition and regeneration of overstory species in present *** the 20-ha Xishuangbanna tropical sea-sonal rainforest dynamics plot in southwestern China,the historical disturbance boundaries were delineated based on panchromatic photographs from *** that drove species clustering in the overstory layer(DBH≥40 cm)were analyzed and the abundance,richness and composition of these species were compared among different tree groups based on multiple regression tree *** coefficient of variation of the brightness value in historical panchro-matic photographs from 1965 was the primary driver of spe-cies clustering in the overstory *** abundance and richness of overstory species throughout the regeneration process were similar,but species composition was always *** the proportion of large-seeded and vigorous-sprouting species showed no significant differ-ence between disturbed and undisturbed forests in the tree-let layer(DBH<20 cm),the difference became significant when DBH *** findings highlight that historical disturbances have strong legacy effects on functional group composition in the overstory and the recovery of overstory species was *** group composi-tion can better indicate the dynamics of overstory species replacement during secondary succession.

关键词： Historical disturbance Legacy effects Secondary forests Overstory species Functional groups

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Effects of Repetitive TranscranialMagnetic Stimulation on Upper Extremity Function in Acute Stroke:A Meta-analysis and Systematic Review

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Medicinal Plant 2024年第5期15卷 50-53页

作者： Chenyang ZHENG wenfu zhang Bao zhang Department of Hydrotherapy and Physiotherapy RehabilitationMedicine CenterTaihe HospitalHubei University of MedicineShiyan 434021China Department of Pediatric Rehabilitation Rehabilitation Medicine CenterTaihe HospitalHubei University of MedicineShiyan 434021China

[Objectives]To conduct a comprehensive examination of the evidence-based impact of repetitive transcranial magnetic stimulation(rTMS)on upper extremity functionality in patients with acute stroke.[Methods]A rigorous and systematic electronic search was conducted across the Medline,PubMed,and Web of Science databases,encompassing literature up to July 1,*** ensure the reliability of the in-cluded studies,an assessment of their risk of bias was conducted using RevMan 5.4 software,in accordance with the rigorous standards out-lined in the Cochrane Handbook for Systematic ***,we employed either the random-effects model or the fixed-effects model,depending on the heterogeneity of the data,to estimate the standardized mean difference(SMD)in outcomes,utilizing Stata 18.0 software for statistical analysis.[Results]Our review encompassed a total of five studies,involving 252 patients with acute *** pooled analysis of these studies revealed a statistically significant improvement in Fugl-Meyer Assessment of the Upper Extremity(FMA-UE)scores among pa-tients who received rTMS therapy(SMD=2.71,95%CI:0.85 to 4.56;P<0.0001),albeit with considerable heterogeneity(I^(2)=97.65%)across the trials.[Conclusions]The results of this systematic review and meta-analysis underscore the promising potential of rTMS in enhancing upper extremity function in patients who have experienced an acute *** findings provide compelling evidence for the therapeutic benefits of rTMS in this patient population.

关键词： Acute stroke rTMS Upper extremity function Meta-analysis

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圆孔工字型蜂窝梁扭转模态自由振动研究

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振动与冲击 2024年第6期43卷 329-335,344页

作者：黄斌张文福南京工程学院建筑工程学院南京211167

从能量等效角度,提出了一种圆孔工字型截面蜂窝梁连续型模型,应用新的薄壁构件扭转理论:板-梁理论,建立了构件扭转模态自由振动能量泛函模型,明确了圆孔工字型截面蜂窝梁名义约束扭转惯性矩(翘曲常数)、自由扭转常数、转动惯量。通过变... 详细信息

从能量等效角度,提出了一种圆孔工字型截面蜂窝梁连续型模型,应用新的薄壁构件扭转理论:板-梁理论,建立了构件扭转模态自由振动能量泛函模型,明确了圆孔工字型截面蜂窝梁名义约束扭转惯性矩(翘曲常数)、自由扭转常数、转动惯量。通过变分运算,获得了平衡微分方程模型。基于扭转模态试函数,推导了圆孔工字型截面蜂窝梁自由振动扭转模态振动圆频率,并与有限元结果对比校验理论模型预测精度。开展了悬臂圆孔工字型蜂窝梁受集中扭矩作用的端部截面转角理论分析与有限元计算,进一步检验了基于板-梁理论建立的蜂窝梁连续模型的适用性。应用板-梁理论对圆孔工字型截面蜂窝梁自由振动扭转的分析过程及推导步骤,为其他开孔类型工字型蜂窝梁扭转模态自由振动研究提供了直接参考。

关键词：圆孔工字型截面蜂窝梁扭转自由振动板-梁理论蜂窝梁连续型模型能量泛函模型

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基于板-梁理论的FGM双轴对称箱形截面组合扭转理论与有限元验证

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南京工程学院学报（自然科学版） 2024年第1期22卷 66-71页

作者：张文福黄鸿杰南京工程学院建筑工程学院江苏南京211167 南京工程学院机械工程学院江苏南京211167

基于板梁理论研究FGM双轴对称箱形截面组合扭转理论与有限元验证.首先,选取弹性模量变化函数,建立能量变分模型,引入无量纲参数,获得双轴对称箱形截面组合扭转的近似解析解;然后,利用微分方程模型计算双轴对称箱形截面组合扭转的精确解... 详细信息

基于板梁理论研究FGM双轴对称箱形截面组合扭转理论与有限元验证.首先,选取弹性模量变化函数,建立能量变分模型,引入无量纲参数,获得双轴对称箱形截面组合扭转的近似解析解;然后,利用微分方程模型计算双轴对称箱形截面组合扭转的精确解析解,给出微分方程解答;最后,利用ANSYS有限元分析软件进行验证,将本文研究所得解析解和ANSYS有限元分析软件得出的解析解进行对比,对比结果验证了本文理论推导及所给出的自由扭转刚度、约束扭转刚度表达式的正确性.

关键词：梯度功能材料板梁理论能量变分模型组合扭转

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基于板-梁理论的FGM矩形截面杆扭转振动的理论研究

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苏州科技大学学报（自然科学版） 2024年第2期41卷 9-16页

作者：张文福周季虎苏州科技大学土木工程学院江苏苏州215011 南京工程学院建筑工程学院江苏南京211167

基于板-梁理论和Saint-Venant扭转理论的研究成果,将纵向位移假设为含有待定系数的表达式,通过几何方程推导了功能梯度材料矩形截面杆的总应变能方程,并利用最小应变能原理确定待定系数,得到自由扭转刚度的理论公式。在此基础上对矩形... 详细信息

基于板-梁理论和Saint-Venant扭转理论的研究成果,将纵向位移假设为含有待定系数的表达式,通过几何方程推导了功能梯度材料矩形截面杆的总应变能方程,并利用最小应变能原理确定待定系数,得到自由扭转刚度的理论公式。在此基础上对矩形截面杆的自由振动出现纯扭转模态时的动能进行研究,求出在夹支条件下的扭转振动时的动能表达式、总势能的表达式及频率表达式。利用有限元软件ANSYS建立具有功能梯度材料特性的矩形截面杆的扭转振动的有限元模型,通过后处理命令查看对应边界条件的振动频率。通过有限元软件验证表明:基于板-梁理论推导得出的理论解与有限元解吻合较好,最大误差在4%以内。

关键词：功能梯度矩形截面杆扭转振动板-梁理论有限元

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原竹快消品加工机械装备发展探究

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世界林业研究 2024年第1期37卷 83-89页

作者：雷军张建张文福朱玲琴袁少飞吴安琪王进浙江省林业科学研究院浙江省竹类研究重点实验室杭州310023 浙江农林大学化学与材料工程学院杭州311300

随着一些国家相继出台限塑令以及我国提出“以竹代塑”倡议,以竹餐具为代表的原竹快消品受到市场越来越多的关注。锯竹、剖竹、开片、截断、成型及热压是原竹快消品加工的主要工序,加工机械的进步直接影响着原竹快消品产业的发展。因此... 详细信息

随着一些国家相继出台限塑令以及我国提出“以竹代塑”倡议,以竹餐具为代表的原竹快消品受到市场越来越多的关注。锯竹、剖竹、开片、截断、成型及热压是原竹快消品加工的主要工序,加工机械的进步直接影响着原竹快消品产业的发展。因此,国内外竹材加工机械研究面临着新的机遇与挑战。文中从加工工序出发,将原竹快消品加工机械分为截断机械、剖竹机械、仿型机械和热压机械4类,以竹刀、竹叉、竹勺、竹吸管等具有代表性的原竹快消品为对象,分析加工工艺技术现状,总结目前国内外原竹快消品加工机械装备研制进展;针对目前竹工机械研究中存在的单机化明显、生产连续性差等问题,提出未来竹工机械应向更加自动化、连续化、智能化的方向发展。

关键词：以竹代塑原竹快消品竹材加工竹工机械自动化

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新文科背景下ChatGPT介入民族传统体育育人的价值指涉与路向

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南京体育学院学报 2024年第2期23卷 13-20页

作者：张文福陈思琦河北师范大学体育学院河北石家庄050024

民族传统体育强调个体、运动、社会之间的整体关系的文化建构,在振兴中国传统文化上有一定优势,有助于拓宽国际话语建构空间,体现中国智慧。推进新文科建设是民族传统体育教育中供给侧结构性改革的重要举措,也是落实立德树人这一教育理... 详细信息

民族传统体育强调个体、运动、社会之间的整体关系的文化建构,在振兴中国传统文化上有一定优势,有助于拓宽国际话语建构空间,体现中国智慧。推进新文科建设是民族传统体育教育中供给侧结构性改革的重要举措,也是落实立德树人这一教育理念的创新路径。在现代科技与文化的交汇点上,以ChatGPT技术介入民族传统体育的新文科教育意味着创新语境中科技对育人的归化,使“全员、全过程、全方位”育人更具操作性。民族传统体育应调动项目特色,重视与ChatGPT的技术融合性、百年大变局的时代性、中华文化伟大复兴的民族性和人类命运共同体建构的国际导向性相结合,创新融通方法论,使以技术为主的议题拓展到综合解决问题能力的广度,让“价值”与“科学”在民族传统体育中共同发挥作用,从而为理论创新和世界文化繁荣提供中国的体育方案和思想价值。

关键词：新文科 ChatGPT 民族传统体育育人价值

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