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Lateral Oxidation in Vertical Cavity Surface Emitting Lasers
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作者 刘文莉 郝永芹 +4 位作者 王玉霞 姜晓光 冯源 李海军 钟景昌 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第8期1351-1354,共4页
Lateral oxidation in vertical cavity surface emitting lasers (VCSELs) is described,and its characteristics are investigated.A linear growth law is found for stripe mesas. However, oxide growth (above 435℃ ) follo... Lateral oxidation in vertical cavity surface emitting lasers (VCSELs) is described,and its characteristics are investigated.A linear growth law is found for stripe mesas. However, oxide growth (above 435℃ ) follows a nonlinear law for the two geometry mesa structures which we employ in VCSEL. Theoretical analysis indicates that mesa structure geometry influences oxide growth rate at higher temperatures. 展开更多
关键词 lateral oxidation quantum well vertical cavity surface emitting laser
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Tropical cyclone secondary eyewall width modulation:Differential impacts of surface environmental wind-vertical shear alignment and counter-alignment configurations
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作者 Yingying Zheng Qingqing Li Yufan Dai 《Atmospheric and Oceanic Science Letters》 2026年第1期7-13,共7页
This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shea... This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shear(VWS),using idealized numerical experiments.Results reveal that the SE develops greater radial extent when surface winds align with VWS compared to counter-aligned conditions.In alignment configurations,shear-enhanced surface winds on the right flank amplify surface enthalpy fluxes,thereby elevating boundary-layer entropy within the downshear outer-core region.Subsequently,more vigorous outer rainbands develop,inducing marked acceleration of tangential winds in the outer core preceding SE formation.The resultant radial expansion of supergradient winds near the boundary-layer top triggers widespread convective activity immediately beyond the inner core.Progressive axisymmetrization of this convective forcing ultimately generates an expansive SE structure. 展开更多
关键词 Tropical cyclone Secondary eyewall width Precipitation vertical wind shear
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Serum Trace Elements and Their Associations with Disease Progression and Survival in Sporadic Amyotrophic Lateral Sclerosis:Insights from a Chinese Cohort
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作者 Hongfen Wang Qionghua Sun +5 位作者 Rongrong Du Shiya Wang Yan Wang Jiongming Bai Mao Li Xusheng Huang 《Biomedical and Environmental Sciences》 2026年第2期183-191,共9页
Objective The associations of serum trace element levels with disease progression and survival duration were assessed in individuals diagnosed with sporadic amyotrophic lateral sclerosis(sALS)in China.Methods Clinical... Objective The associations of serum trace element levels with disease progression and survival duration were assessed in individuals diagnosed with sporadic amyotrophic lateral sclerosis(sALS)in China.Methods Clinical data,including diagnostic indicators,clinical characteristics,Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised(ALSFRS-R)scores,and serum concentrations of calcium(Ca),magnesium(Mg),iron(Fe),copper(Cu),and zinc(Zn),were collected for hospitalized patients with sALS between 2018 and 2021.Correlation analysis,random forest analysis,and the Gehan-Breslow-Wilcoxon test were used to evaluate the relations between serum trace element levels,disease progression,and survival duration.Results Lower serum Ca levels and higher Mg levels were observed in patients with ALSFRS-R scores<39.Serum Mg was significantly negatively correlated with ALSFRS-R,trunk,and respiratory scores.Serum Cu and Zn also showed significant negative correlations with the respiratory score,whereas Ca and Fe were not significantly correlated with the ALSFRS-R score.The serum levels of Ca,Mg,Cu,Zn,and Fe remained consistent regardless of the site of disease onset.ALSFRS-R analysis revealed that serum Ca and Mg had a substantial effect on the total ALSFRS-R score,with serum Mg significantly influencing the course of the disease.Notably,low serum Mg levels were associated with extended survival times in patients with sALS.Conclusion Serum levels of Ca and Mg play critical roles in the progression of sALS,and a reduced serum Mg level is related to an extended survival time. 展开更多
关键词 Amyotrophic lateral sclerosis Metal/metalloid Microelement Risk factor
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Vertical Structure and Energy Transfer of Stationary Planetary Waves in Different Prescribed Atmospheric Stratifications
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作者 Wenqi ZHANG Lin WANG 《Advances in Atmospheric Sciences》 2026年第1期233-246,共14页
This study investigates the relationship between atmospheric stratification (i.e., static stability given by N^(2)) and the vertical energy transfer of stationary planetary waves, and further illustrates the underlyin... This study investigates the relationship between atmospheric stratification (i.e., static stability given by N^(2)) and the vertical energy transfer of stationary planetary waves, and further illustrates the underlying physical mechanism. Specifically, for the simplified case of constant stratospheric N^(2), the refractive index square of planetary waves has a theoretical tendency to increase first and then decrease with an increased N^(2), whereas the group velocity weakens. Mechanistically, this behavior can be understood as an intensified suppression of vertical isentropic surface displacement caused by meridional heat transport of planetary waves under strong N^(2) conditions. Observational analysis corroborates this finding, demonstrating a reduction in the vertical-propagation velocity of waves with increased N^(2). A linear, quasi- geostrophic, mid-latitude beta-plane model with a constant background westerly wind and a prescribed N^(2) applicable to the stratosphere is used to obtain analytic solutions. In this model, the planetary waves are initiated by steady energy influx from the lower boundary. The analysis indicates that under strong N^(2) conditions, the amplitude of planetary waves can be sufficiently increased by the effective energy convergence due to the slowing vertical energy transfer, resulting in a streamfunction response in this model that contains more energy. For N^(2) with a quasi-linear vertical variation, the results bear a resemblance to the constant case, except that the wave amplitude and oscillating frequency show some vertical variations. 展开更多
关键词 planetary waves vertical propagation atmospheric stratification stratospheric circulation group velocity
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Vertical Handover Algorithm Based on Network State Prediction
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作者 Xu Yanyan Wang Yixiao +1 位作者 Xu Yue Pan Shaoming 《China Communications》 2026年第2期162-180,共19页
The dense heterogeneous network provides standardized connectivity and access guarantees for 5G communication services.However,the complex network environment and high level of dynamism pose challenges to network sele... The dense heterogeneous network provides standardized connectivity and access guarantees for 5G communication services.However,the complex network environment and high level of dynamism pose challenges to network selection decisions.Existing vertical handover algorithms often overlook the dynamic nature of user mobility and network condition,resulting in problems such as handover failure and frequent handover,ultimately impacting the quality of the user communication service.To address these problems,we propose an intelligent switching method,iMALSTM-DQN,which integrates an improved Multi-level Associative Long Short-Term Memory model(iMALSTM)with Deep Reinforcement Learning(DRL).The algorithm leverages iMALSTM to predict the global network state in the next moment based on the global user movement trajectory and historical network status information within a region,thereby enhancing the prediction accuracy of network states.Subsequently,based on the predicted network state,we employ the Deep Q Network(DON)model to make handover decisions,adaptively determining the optimal switching and network selection strategy through interaction with the environment.Experimental results demonstrate that the proposed algorithm enhances decision timeliness,significantly reduces the number of switch failures,and alleviates the problem of frequent handovers resulting from network dynamics. 展开更多
关键词 deep reinforcement learning dense heterogeneous networks state prediction vertical handover
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Vertical Interfacial Engineering in Two-Step-Processed Perovskite Films Enabled by Dual-Interface Modification for High-Efficiency p-i-n Solar Cells
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作者 Wenhao Zhou Heng Liu +8 位作者 Haiyan Li Weihai Zhang Hui Li Xia Zhou Rouxi Chen Wenjun Zhang Tingting Shi Antonio Abate Hsing-Lin Wang 《Nano-Micro Letters》 2026年第5期405-423,共19页
Two-step-processed(TSP)inverted p-i-n perovskite solar cells(PSCs)have demonstrated significant promise in tandem applications.However,the power conversion efficiency(PCE)of TSP p-i-n PSCs rarely exceeds 24%.Here,we d... Two-step-processed(TSP)inverted p-i-n perovskite solar cells(PSCs)have demonstrated significant promise in tandem applications.However,the power conversion efficiency(PCE)of TSP p-i-n PSCs rarely exceeds 24%.Here,we demonstrate that TSP perovskite films exhibit a vertically gradient distribution of residual PbI_(2)clusters,which form Schottky heterojunctions with the perovskite,leading to substantial interfacial energy-level mismatches within NiO_(x)-based TSP p-i-n PSCs.These limitations were effectively addressed via a vertical interfacial engineering enabled by dual-interface modification incorporating tin trifluoromethanesulfonate(Sn(OTF)_(2))and 4-Fluorophenylethylamine chloride(F-PEA)at the NiO_(x)/perovskite and perovskite/C60 interfaces,respectively.The functional Sn(OTF)_(2)not only enhances the conductivity of NiO_(x)films but also suppresses ion migration,while inducing the formation of a Pb-Sn mixed perovskite interlayer that precisely regulates the energy level at the NiO_(x)/perovskite interface.Complementally,F-PEA post-treatment effectively converts surface residual PbI_(2)clusters into a 2D perovskite capping layer,which simultaneously passivates surface defects and enhances energy-level alignment at the perovskite/C60 interface.Consequently,the optimized NiO_(x)-based TSP p-i-n PSCs achieve a notable PCE of 25.6%with superior operational stability.This study elucidates the underlying mechanisms limiting the efficiency of TSP p-i-n PSCs,while establishing design principles for these devices targeting 26%efficiency. 展开更多
关键词 vertical interfacial engineering Interface modification Energy-level modulation Nickle oxide Two-step procession
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Observation and Simulation of Vertically Resolved Nitrous Acid(HONO) in Autumn over Urban Beijing, China
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作者 Jiawen TANG Shanshan WANG +8 位作者 Zhibin SUN Yuhao YAN Jian ZHU Sanbao ZHANG Ruibin XUE Jiaqi LIU Guiqian TANG Wenkang GAO Bin ZHOU 《Advances in Atmospheric Sciences》 2026年第2期405-419,I0010-I0021,共27页
As a key precursor of hydroxyl(OH) radicals, the budget of nitrous acid(HONO) at different altitudes has received extensive attention. In this study, vertically resolved observations of HONO, NO_(2), O_(3), and HCHO w... As a key precursor of hydroxyl(OH) radicals, the budget of nitrous acid(HONO) at different altitudes has received extensive attention. In this study, vertically resolved observations of HONO, NO_(2), O_(3), and HCHO were conducted during an autumn field campaign in Beijing in 2019. The significant correlation between HONO and NO2, along with variations in their ratios across different altitudes, underscores the importance of aerosol surface chemistry in HONO formation and its altitude-dependent behavior. To enhance the model performance, the heterogeneous conversion of NO_(2) and its photochemical enhancement are incorporated into the 1D model. The simulations reveal that the nocturnal HONO production is dominated by the heterogeneous conversion of NO_(2) both at the surface and aloft. During the daytime, groundsurface sources of HONO are mainly driven by nitrate photolysis and light-enhanced heterogeneous conversion of NO_(2).Meanwhile, a large portion of the HONO generated at the surface is transported upwards through vertical mixing. In the higher atmosphere, HONO originates from vertical transport and in situ processes. As precursors of OH radicals, the observed concentrations of HONO, O_(3), and HCHO exhibit distinct diurnal variations and vertical distribution patterns.HONO contributes to OH radical production predominantly during the early morning across all layers and it even becomes the main contributor throughout the daytime in the lowest layer near the ground, while O_(3) and HCHO become more prominent towards midday, especially in the higher layers. These results will be beneficial for a deeper understanding of the atmospheric oxidation process within the urban boundary layer. 展开更多
关键词 HONO differential optical absorption spectroscopy vertical distribution 1D model OH radicals
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Optical lateral flow immune assay technology for body fluid sensing
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作者 Chen Liu Tianqi Zhao +5 位作者 Jialing Zhou Xiaoyun Hu Dinghao Pan Jinlong Li Wei Li Zhihui Dai 《Chinese Chemical Letters》 2026年第1期106-115,共10页
Detecting biomarkers in body fluids by optical lateral flow immune assay(LFIA) technology provides rapid access to disease information for early diagnosis.LFIA is based on an antigen-antibody reaction and is rapidly b... Detecting biomarkers in body fluids by optical lateral flow immune assay(LFIA) technology provides rapid access to disease information for early diagnosis.LFIA is based on an antigen-antibody reaction and is rapidly becoming the preferred choice of physicians and patients for point-of-care testing due to its simplicity,cost-effectiveness,and rapid detection.Observing the optical signal change from the colloidal gold of the traditional LFIA strip has been widely applied for various biomarkers detection in body fluids.Despite the significant progress,rapid real-time detection of color changes in the colloidal gold by the naked eye still faces many limitations,such as large errors and the inability to quantify and accurately detect.New optical LFIA strip technology has emerged in recent years to extend its application scenarios for achieving quantitative detection such as fluorescence,afterglow,and chemiluminescence.Herein,we summarized the development of optical LFIA technology from single to hyphenated optical signals for biomarkers detection in body fluids from invasive and non-invasive sources.Moreover,the challenge and outlook of optical LFIA strip technology are highlighted to inspire the designing of next-generation diagnostic platforms. 展开更多
关键词 Optical signal lateral flow immune assay Hyphenated optical technology Body fluid sensing Point-of-care testing
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UGEA-LMD: A Continuous-Time Dynamic Graph Representation Enhancement Framework for Lateral Movement Detection
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作者 Jizhao Liu Yuanyuan Shao +2 位作者 Shuqin Zhang Fangfang Shan Jun Li 《Computers, Materials & Continua》 2026年第1期1924-1943,共20页
Lateral movement represents the most covert and critical phase of Advanced Persistent Threats(APTs),and its detection still faces two primary challenges:sample scarcity and“cold start”of new entities.To address thes... Lateral movement represents the most covert and critical phase of Advanced Persistent Threats(APTs),and its detection still faces two primary challenges:sample scarcity and“cold start”of new entities.To address these challenges,we propose an Uncertainty-Driven Graph Embedding-Enhanced Lateral Movement Detection framework(UGEA-LMD).First,the framework employs event-level incremental encoding on a continuous-time graph to capture fine-grained behavioral evolution,enabling newly appearing nodes to retain temporal contextual awareness even in the absence of historical interactions and thereby fundamentally mitigating the cold-start problem.Second,in the embedding space,we model the dependency structure among feature dimensions using a Gaussian copula to quantify the uncertainty distribution,and generate augmented samples with consistent structural and semantic properties through adaptive sampling,thus expanding the representation space of sparse samples and enhancing the model’s generalization under sparse sample conditions.Unlike static graph methods that cannot model temporal dependencies or data augmentation techniques that depend on predefined structures,UGEA-LMD offers both superior temporaldynamic modeling and structural generalization.Experimental results on the large-scale LANL log dataset demonstrate that,under the transductive setting,UGEA-LMD achieves an AUC of 0.9254;even when 10%of nodes or edges are withheld during training,UGEA-LMD significantly outperforms baseline methods on metrics such as recall and AUC,confirming its robustness and generalization capability in sparse-sample and cold-start scenarios. 展开更多
关键词 Advanced persistent threat(APTs) lateral movement detection continuous-time dynamic graph data enhancement
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Electro-mechanical-carrier coupling model in fractured piezoelectric semiconductor strip with vertical cracks
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作者 Cai REN Kaifa WANG Baolin WANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第2期347-368,共22页
Understanding the fracture behavior of vertical cracks in piezoelectric semiconductor(PS)structures is vital due to their impacts on device reliability.This study establishes a model for a PS strip with a vertical cra... Understanding the fracture behavior of vertical cracks in piezoelectric semiconductor(PS)structures is vital due to their impacts on device reliability.This study establishes a model for a PS strip with a vertical crack under combined mechanical and electric loading,considering both central and edge cracks.Using Fourier transforms and dislocation density functions,the Mode-Ⅲproblem is converted to Cauchy-type singular integral equations.The crack surface fields,intensity factors,and energy release rate are derived.The accuracy of the proposed model is verified through the finite element(FE)simulation via COMSOL Multiphysics.The results for low electron concentrations align with those of the intrinsic piezoelectric materials,validating the correctness of the present model as well.The combined effects of crack position,applied electric loading,and initial carrier concentration on the crack propagation are analyzed.The normalized electric displacement factor shows heightened sensitivity to crack size,electromechanical loading,and carrier concentration.The crack position significantly influences the crack surface fields and normalized intensity factors due to the boundary proximity effect. 展开更多
关键词 piezoelectric semiconductor(PS) vertical crack singular integral equation electro-mechanical-carrier coupling extended intensity factor
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Unraveling the missing heritability of amyotrophic lateral sclerosis:Should we focus more on copy number variations?
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作者 Maria Guarnaccia Valentina La Cognata +2 位作者 Giulia Gentile Giovanna Morello Sebastiano Cavallaro 《Neural Regeneration Research》 2026年第5期1997-1998,共2页
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive degeneration of upper and lower motor neurons in the brainstem and spinal cord,leading to muscle weakness,para... Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive degeneration of upper and lower motor neurons in the brainstem and spinal cord,leading to muscle weakness,paralysis,and respiratory failure (Morgan and Orrell,2016). 展开更多
关键词 degeneration upper lower motor neurons unraveling neurodegenerative disorder missing heritability amyotrophic lateral sclerosis copy number variations
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Comprehensive clinical and genetic architecture of familial amyotrophic lateral sclerosis in China:A 15-year cohort study with 302 families
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作者 Wei Zheng Lu Xu +6 位作者 Jinling Cai Jinwen Hou Lu Chen Nan Zhang Siyan Zhan Dongsheng Fan Ji He 《Neural Regeneration Research》 2026年第6期2573-2579,共7页
The growing recognition of the role of genetics in the development of amyotrophic lateral sclerosis is evident.However,there has yet to be a comprehensive analysis of the clinical characteristics and genetics of famil... The growing recognition of the role of genetics in the development of amyotrophic lateral sclerosis is evident.However,there has yet to be a comprehensive analysis of the clinical characteristics and genetics of familial amyotrophic lateral sclerosis in an Asian population.This study aimed to provide an in-depth analysis of the clinical features and genetic spectrum of familial amyotrophic lateral sclerosis over 15 years in a clinic-based cohort of patients from the Chinese mainland.Enrollment of 302 amyotrophic lateral sclerosis families from 28 provinces was undertaken from January 2008 to September 2023.A group-based trajectory model for disease progression based on amyotrophic lateral sclerosis Functional Rating Scale-Revised(ALSFRS-R)scores was validated using bootstrap internal validation in patients with familial amyotrophic lateral sclerosis,as well as patients with sporadic amyotrophic lateral sclerosis(matched at a 1:4 ratio,with replacement).DNA samples from 244 index patients were screened for variants in the pathogenic genes SOD1,FUS,TDP43,and C9ORF72,of which 146 were also subjected to genome-wide next-generation sequencing.Gene-level burden analysis was used to evaluate the distribution of rare variants in the cohort.We found that rapid dynamic disease progression was associated with an older age at onset,shorter diagnostic delay,lower body mass index,bulbar onset,and≥1 affected first-degree relative.Certain attributes,such as age at onset and time from onset to diagnosis,had comparable impacts on the clinical progression trajectories of both familial amyotrophic lateral sclerosis and sporadic amyotrophic lateral sclerosis.Harboring pathogenic/likely pathogenic variants in amyotrophic lateral sclerosis-causative genes reduced the age of onset of familial amyotrophic lateral sclerosis.Among the patients with familial amyotrophic lateral sclerosis,17.8%possessed≥2 pathogenic/likely pathogenic variants.Sequencing kernel association test analysis showed that the SOD1 rare variant burden(P=1.3e-15)was associated with a significant risk of familial amyotrophic lateral sclerosis.Our findings conclusively confirmed the clinical features and genetic spectrum of familial amyotrophic lateral sclerosis over 15 years in a clinical cohort from China,contributing to a deeper understanding of genotype-phenotype relationships in familial amyotrophic lateral sclerosis.This comprehensive evaluation of specific clinical characteristics,clinical prognosis,and genetic variants of amyotrophic lateral sclerosis based on detailed clinical and genetic information may lead to the development of genotype-specific treatment approaches. 展开更多
关键词 China COHORT EPIDEMIOLOGICAL familial amyotrophic lateral sclerosis gene-level burden analysis genetic GENOTYPE group-based trajectory model PATHOGENIC PHENOTYPE
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Influence of vertical loads on lateral response of pile foundations in sands and clays 被引量:10
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作者 Lassaad Hazzar Mahmoud N.Hussien Mourad Karray 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第2期291-304,共14页
Although the load applied to pile foundations is usually a combination of vertical and lateral components,there have been few investigations on the behavior of piles subjected to combined loadings.Those few studies le... Although the load applied to pile foundations is usually a combination of vertical and lateral components,there have been few investigations on the behavior of piles subjected to combined loadings.Those few studies led to inconsistent results with regard to the effects of vertical loads on the lateral response of piles.A series of three-dimensional(3D) finite differences analyses is conducted to evaluate the influence of vertical loads on the lateral performance of pile foundations.Three idealized sandy and clayey soil profiles are considered:a homogeneous soil layer,a layer with modulus proportional to depth,and two-layered strata.The pile material is modeled as linearly elastic,while the soil is idealized using the Mohr-Coulomb constitutive model with a non-associated flow rule.In order to confirm the findings of this study,soils in some cases are further modeled using more sophisticated models(i.e.CYsoil model for sandy soils and modified Cam-Clay(MCC) model for clayey soils).Numerical results showed that the lateral resistance of the piles does not appear to vary considerably with the vertical load in sandy soil especially at the loosest state.However,the presence of a vertical load on a pile embedded in homogeneous or inhomogeneous clay is detrimental to its lateral capacity,and it is unconservative to design piles in clays assuming that there is no interaction between vertical and lateral loads.Moreover,the current results indicate that the effect of vertical loads on the lateral response of piles embedded in twolayered strata depends on the characteristics of soil not only surrounding the piles but also located beneath their tips. 展开更多
关键词 Pile foundations vertical loads lateral loads Finite differences Mohr circle
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Key technologies of vertical take-off and landing infrastructure for urban air mobility:a comprehensive review
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作者 Chenglong LI Runming WANG +3 位作者 Zhaoxuan ZHANG Yuan ZHENG Yang WANG Rui YANG 《ENGINEERING Information Technology & Electronic Engineering》 2026年第1期19-46,共28页
As the frontier of multidimensional transportation systems,urban air mobility(UAM)is receiving increasing attention from international organizations,governments,and stakeholders in industry and academia owing to its h... As the frontier of multidimensional transportation systems,urban air mobility(UAM)is receiving increasing attention from international organizations,governments,and stakeholders in industry and academia owing to its high efficiency,low carbon footprint,and operational flexibility.Vertical take-off and landing(VTOL)infrastructure is the core facility that enables UAM and is therefore essential for its safe,efficient,and large-scale commercial implementation.However,the key technologies for establishing low-altitude VTOL infrastructure are still nascent,and government,industry,and academia have yet to harmonize the corresponding construction,management,and operation standards.To address this gap,we herein systematically review the related progress and trends,comprehensively surveying the key technologies of establishing VTOL infrastructure serving unmanned aerial vehicles(UAVs)and electric VTOL aircraft from three complementary perspectives of ground-side,airspace-side,and communication,navigation,surveillance,and information services.In the light of future UAM operations characterized by diverse vehicle types and dense air traffic,we propose a conceptual design for a public multioperator VTOL site to provide constructive insights into the sustainable growth of the low-altitude economy. 展开更多
关键词 Urban air mobility(UAM) vertical take-off and landing(VTOL)infrastructures Low-altitude operations Communication navigation surveillance and information(CNSI)
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Elastoplastic solutions for single piles under combined vertical and lateral loads 被引量:17
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作者 ZHANG Lei GONG Xiao-nan +1 位作者 YANG Zhong-xuan YU Jian-lin 《Journal of Central South University》 SCIE EI CAS 2011年第1期216-222,共7页
In order to improve the reliability of the design and calculation of single piles under the combined vertical and lateral loads, the solutions were presented based on the subgrade reaction method, in which the ultimat... In order to improve the reliability of the design and calculation of single piles under the combined vertical and lateral loads, the solutions were presented based on the subgrade reaction method, in which the ultimate soil resistance was considered and the coefficient of subgrade reaction was assumed to be a constant. The corresponding computational program was developed using FORTRAN language. A comparison between the obtained solutions and the model test results was made to show the validity of the obtained solutions. The calculation results indicate that both the maximum lateral displacement and bending moment increase with the increase of the vertical and lateral loads and the pile length above ground, while decrease as the pile stiffness, the coefficient of subgrade reaction and the yielding displacement of soil increase. It is also shown that the pile head condition controls the pile responses and the vertical load may cause the instability problem to the pile. In general, the proposed method can be employed to calculate the pile responses independent of the magnitude of the pile deflection. 展开更多
关键词 pile-soil interaction combined vertical and lateral loads ultimate resistance subgrade reaction method bendingmoment
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Using Geochemical Method to Distinguish Lateral Migration and Vertical Migration in Rifted Basin:A Case Study from Eastern Lujiapu Depression in the Kailu Basin,NE China 被引量:3
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作者 ZHOU Shuqing HUANG Haiping LIU Yuming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期669-678,共10页
Migration fractionation diagnosis is complicated in rifted basins where migration distance is generally short and lateral migration in sandy beds and vertical migration along faults are co-existed. Quantitative data f... Migration fractionation diagnosis is complicated in rifted basins where migration distance is generally short and lateral migration in sandy beds and vertical migration along faults are co-existed. Quantitative data from GC-MS analysis makes it possible to distinguish lateral and vertical migration effects. Oils discovered from the Jiaolige oilfield, eastern Lujiapu Depression are derived from single source rock with similar maturity, which is an ideal case to study the migration fractionation effects. Compositional differences among oils are largely caused by the migration fractionation either laterally in sand beds or vertically along the faults. Subtle maturity differences are assessed by the classic saturated hydrocarbon parameters which have certain influence on nitrogen compounds. In a certain maturity range, the ratios of shield and semi-shield isomers to the exposed isomers of alkylcarbazoles change with maturity in an opposite direction with migration fractionation, which may conceal the migration influence. However, migration and maturation have the same effects on absolute concentrations of alkylated carbazoles and benzocarbazole [a]/([a]+[c]) ratios, which provides an ideal tool for migration direction assessment. Continuous variations among different samples reflect increased migration distance in sandy beds, while abrupt changes may indicate the change of migration conduit systems. Integrated both geochemical interpretation and geological constrains, not only migration direction can be determined, but also the conduit systems through the sandy beds or the faults can be recognized. 展开更多
关键词 Kailu Basin BIOMARKER nitrogen compounds lateral migration vertical migration
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Energetics of lateral eddy diffusion/advection: Part I. Thermodynamics and energetics of vertical eddy diffusion 被引量:5
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作者 HUANG Rui Xin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第3期1-18,共18页
Two important nonlinear properties of seawater thermodynamics linked to changes of water density, cab beling and elasticity (compressibility), are discussed. Eddy diffusion and advection lead to changes in den sity;... Two important nonlinear properties of seawater thermodynamics linked to changes of water density, cab beling and elasticity (compressibility), are discussed. Eddy diffusion and advection lead to changes in den sity; as a result, gravitational potential energy of the system is changed. Therefore, cabbeling and elasticity play key roles in the energetics of lateral eddy diffusion and advection. Vertical eddy diffusion is one of the key elements in the mechanical energy balance of the global oceans. Vertical eddy diffusion can be con ceptually separated into two steps: stirring and subscale diffusion. Vertical eddy stirring pushes cold/dense water upward and warm/light water downward; thus, gravitational potential energy is increased. During the second steps, water masses from different places mix through subscale diffusion, and water density is increased due to cabbeling. UsingWOA01 climatology and assuming the vertical eddy diffusivity is equal to a constant value of 2x103 pa2/s, the total amount of gravitational potential energy increase due to vertical stirring in the world oceans is estimated at 263 GW. Cabbeling associated with vertical subscale diffusion is a sink of gravitational potential energy, and the total value of energy lost is estimated at 73 GW. Therefore, the net source of gravitational potential energy due to vertical eddy diffusion for the world oceans is estimated at 189 GW. 展开更多
关键词 cabbeling COMPRESSIBILITY elasticity energetics of vertical eddy diffusion gravitationalpotential energy parameterization of eddy diffusion
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Behaviour of Batter Micropiles Subjected to Vertical and Lateral Loading Conditions 被引量:2
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作者 Binu Sharma Zakir Hussain 《Journal of Geoscience and Environment Protection》 2019年第2期206-220,共15页
Micropiles are drilled and grouted piles having diameter between 100 to 250 mm. Due to its small diameter, it is suitable for low headroom and limited work area conditions. It can be installed without noise nuisance, ... Micropiles are drilled and grouted piles having diameter between 100 to 250 mm. Due to its small diameter, it is suitable for low headroom and limited work area conditions. It can be installed without noise nuisance, without vibrations to surrounding soils and structures and without disruption to the production operations in industries which makes micropiles suitable for underpinning and seismic retrofitting of structures. It is necessary to therefore understand the behaviour of micropiles under different loading conditions. This work is on vertical and battered micropiles with different length/diameter ratio (L/D) subjected to vertical and lateral loading conditions. Batter angles had a significant influence on both the vertical and lateral load carrying capacity. The ultimate vertical load was found to increase upto a 30&#176;batter. The ultimate lateral load was found to increase significantly with increasing L/D ratios upto an L/D ratio of 30 for vertical and 48 for battered piles, beyond which the increase was found to be not significant. In general, negative battered micropiles offered more lateral resistance than positive battered micropiles. The results of the study indicated that the ultimate load capacity and mode of failure of the micropiles are a function of the angle of batter, direction of batter and the L/D ratio for vertically and laterally loaded micropiles. 展开更多
关键词 BATTER Micropiles vertical LOAD lateral LOAD LENGTH to DIAMETER Ratio Failure Mechanism
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Lateral rectus muscle recession and the vertical palpebral fissure height: to do or not to do inter-muscular septum dissection? 被引量:1
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作者 Mohammad Ali Abtahi Alireza Zandi +3 位作者 Eslam Mandegarfard Hamidreza Jahanbani-Ardakani Behzad Mahaki Seyed-Hossein Abtahi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第6期1053-1055,共3页
In this study, we aimed to evaluate changes of vertical palpebral fissure height (VPFH) after unilateral lateral rectus muscle recession. Twenty-five and twenty-six patients who were candidates for lateral rectus mu... In this study, we aimed to evaluate changes of vertical palpebral fissure height (VPFH) after unilateral lateral rectus muscle recession. Twenty-five and twenty-six patients who were candidates for lateral rectus muscle recession were assigned into “with” and “without” intermuscular septum dissection study arms. The VPFH was measured at one-day before surgery and in two weeks and three months, postoperatively. Three months after surgery, significant increase of VPFH was observed in both groups (Paired t-test; P=0.005). Also, less widening of VPFH was observed in “with intermuscular septum dissection” group (Change in VPFH in “with intermuscular septum dissection” vs “without intermuscular septum dissection” groups: 0.48 mm vs 1.34 mm; ANCOVA test; P〈0.001). However, such results were not observed two weeks post-operatively (Change in VPFH in “with intermuscular septum dissection” vs “without intermuscular septum dissection” groups: -0.28 mm vs 0.28 mm; ANCOVA test; P=0.302). Intermuscular septum dissection is recommended in lateral rectus muscle recession to partially prevent the undesirable increment of VPFH. 展开更多
关键词 intermuscular septum lateral rectus muscle recession vertical palpebral fissure height
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Influence of Vertical Load on Lateral-Loaded Monopiles by Numerical Simulation 被引量:1
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作者 Qiang Li Pan Chen +2 位作者 Lihong Gao Dan Meng Jinjie Zou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期465-481,共17页
Monopiles are the most common foundation form of offshore wind turbines,which bear the vertical load,lateral load and bending moment.It remains uncertain whether the applied vertical load increases the lateral deflect... Monopiles are the most common foundation form of offshore wind turbines,which bear the vertical load,lateral load and bending moment.It remains uncertain whether the applied vertical load increases the lateral deflection of the pile.This paper investigated the influence of vertical load on the behaviour of monopiles installed in the sand under combined load using three-dimensional numerical methods.The commercial software PLAXIS was used for simulations in this paper.Monopiles were modelled as a structure incorporating linear elastic material behaviour and soil was modelled using the Hardening-Soil(HS)constitutive model.The monopiles under vertical load,lateral load and combined vertical and lateral loads were respectively studied taking into account the sequence of load application and pile slenderness ratio(L/D;L and D are the length and diameter of the pile).Results suggest that the sequence of load application plays a major role in how vertical load affects the deflection behaviour of the pile.Specifically,when L/D ratios obtained by lengthening the pile while keeping its diameter constant are 3,5 and 8,the relationships between lateral load and the deflection behaviour of the pile under the effect of vertical load demonstrate a similar trend.Furthermore,the cause of increased lateral capacity of the pile under the action of applied vertical load in the common practical application case and in the VPL case was analyzed by studying the variation law of soil stress along the pile embedment.Results confirm that the confining effect of vertical load increases means effective stress of the soil around the pile,thus increasing soil stiffness and pile capacity. 展开更多
关键词 PILE lateral capacity combined load sequence of load application L/D ratio
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