Results 11 to 20 of about 10,428 (167)

Anthropogenic nitrogen addition interrupts seasonal connectivity and structures of plant–pollinator networks

open access: yesFunctional Ecology, EarlyView.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Ecological communities are stressed by rapid and complex anthropogenic changes, threatening the persistence of biotic interactions and ecosystem functioning. Plant–pollinator communities, for instance, undergo structural transformations as a result of land‐use change ...
Erliang Gao   +8 more
wiley   +1 more source

Rapid construction of insect–plant interaction networks via multiplexed long‐fragment DNA metabarcoding and NGS

open access: yesMethods in Ecology and Evolution, EarlyView.
Abstract Molecular identification of insect food webs can accurately reveal complex trophic interactions and serve as a foundation for understanding ecosystem functioning and advancing biodiversity conservation. This process typically involves DNA library construction, high‐throughput sequencing and subsequent steps, including data assembly, annotation,
Xiao‐man Zhang   +9 more
wiley   +1 more source

Controlling influence of the “perched water structure” on rainfall-induced landslide: A case study of the Yaogou landslide in Zhushan County, Hubei Province [PDF]

open access: yes
The Yaogou landslide, located in Zhushan County, Hubei Province, exhibits distinctive aquifer characteristics and varying permeability, leading to the retention of groundwater within the landslide after rainfall, forming confined water.
Lihua LI   +3 more
core   +1 more source

薄壁不锈钢圆管柱轴压稳定性能研究

open access: yesJianzhu Gangjiegou Jinzhan, 2023
利用ABAQUS有限元软件对薄壁不锈钢圆管轴压柱的轴压稳定性能进行了数值模拟,并考察了材料性能参数、材料各向异性、初始几何缺陷、径厚比、长细比等因素的影响。分析结果表明:材料各向异性和初始局部缺陷的取值对构件轴压稳定性能影响较小,可以忽略;初始整体缺陷取值对构件轴压稳定性能影响较大,有限元模型中取构件长度的1/2 000可较为准确地模拟试验结果;材料性能参数、径厚比和长细比对构件轴压稳定性能影响较大。通过对不同径厚比构件的分析,提出了防止构件发生局部屈曲的容许径厚比建议公式 ...
朱浩川, 许友武, 姚谏
doaj  

Research on Dynamic Stock Selection by Panel Logit Model Based on Financial Data and Valuation Index [PDF]

open access: yes, 2015
本文通过主成分分析方法以及面板Logit模型建立了一个基于财务与估值指标的动态选股模型,使其既可为一个长期的选股策略被单独使用;亦可为事件型选股以及市场技术面选股提供一个先期的初选股票池,以提高量化选股的科学性和严谨性。针对财务数据和市场数据更新频率不同的难题,提供了一个两阶段的股票筛选方法;同时在进行个股投资时,也能为个股的财务基本面进行综合评分,以辅助投资者进行投资决策。 在模型构建的过程中,本文运用了更符合实际的数据处理方式。同时专注于有效信息挖掘,避免在因子规模上进行粗放式竞争 ...
杨松
core  

Research on lateral load reduction mechanism of anchored sheet pile wall by deep cement mixing pile in active zone [PDF]

open access: yes
The lateral retaining effect of deep cement mixing piles has gradually gained attention in the application of retaining structures, such as foundation pits and wharves in soft soil areas.
CHEN Shengyuan, DAI Jiqun, GUAN Yunfei , CAI Zhengyin, HAN Xun
core   +1 more source

Biodiversity‐driven spatial conservation planning to delineate temporally stable regions

open access: yesConservation Biology, EarlyView.
Abstract The accelerating loss of biodiversity underscores the critical need for effective conservation strategies, particularly in the face of climate change and anthropogenic pressures. We devised a conservation planning framework that adopts a temporal stacking approach to species distribution models and landscape connectivity analyses. These models
Mattia Iannella   +5 more
wiley   +1 more source

Application and Prospect of AI Technology in Power System Development [PDF]

open access: yes
[Introduction] In the face of energy scarcity and carbon reduction imperatives, the transition to clean energy centered on electricity is crucial.
Bin SHU   +4 more
core   +1 more source

Interfacial Engineering of Sodiophilic Metal Layers on Liquid Alloys for Dendrite‐Free Sodium Metal Anodes

open access: yesRare Metals, Volume 45, Issue 5, May 2026.
ABSTRACT Sodium metal batteries hold significant promise for large‐scale energy storage due to the high theoretical capacity and abundant sodium sources, yet sodium‐metal anodes are hindered by dendrite propagation, unstable solid electrolyte interphase, and poor cycling efficiency arising from uneven Na deposition and volume changes.
Nan Xing   +7 more
wiley   +1 more source

砌体防倒塌钢桁架加固方法研究 [PDF]

open access: yes, 2011
上世纪后30年,我国建造了大量砌体结构,而现用中小学校舍占有其中相当的比例。对于砌体结构的改造与加固在现时代仍具有十分重要的意义。本文提出了一种利用钢桁架对砌体结构进行防倒塌加固的方法,包括计算假定以及设计理论,并且给出了该加固方法的设计流程。分析表明,防倒塌钢桁架加固方法,在提高结构系统的安全储备方面可以发挥重要作用 ...
廖子建, 张鹏程, 林树枝, 肖伟
core  

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