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A Chinese Abbreviation Prediction Framework Based on Chain-of-Thought Prompting and Semantic Preservation Dynamic Adjustment
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作者 Jingru Lv Jianpeng Hu +1 位作者 Jin Zhao Yonghao Luo 《Computers, Materials & Continua》 2026年第4期1530-1547,共18页
Chinese abbreviations improve communicative efficiency by extracting key components from longer expressions.They are widely used in both daily communication and professional domains.However,existing abbreviation gener... Chinese abbreviations improve communicative efficiency by extracting key components from longer expressions.They are widely used in both daily communication and professional domains.However,existing abbreviation generation methods still face two major challenges.First,sequence-labeling-based approaches often neglect contextual meaning by making binary decisions at the character level,leading to abbreviations that fail to capture semantic completeness.Second,generation-basedmethods rely heavily on a single decoding process,which frequently produces correct abbreviations but ranks them lower due to inadequate semantic evaluation.To address these limitations,we propose a novel two-stage frameworkwithGeneration–Iterative Optimization forAbbreviation(GIOA).In the first stage,we design aChain-of-Thought prompting strategy and incorporate definitional and situational contexts to generate multiple abbreviation candidates.In the second stage,we introduce a Semantic Preservation Dynamic Adjustment mechanism that alternates between character-level importance estimation and semantic restoration to optimize candidate ranking.Experiments on two public benchmark datasets show that our method outperforms existing state-of-the-art approaches,achieving Hit@1 improvements of 15.15%and 13.01%,respectively,while maintaining consistent results in Hit@3. 展开更多
关键词 ABBREVIATION chain-of-thought prompting semantic preservation dynamic adjustment candidate ranking
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CAWASeg:Class Activation Graph Driven Adaptive Weight Adjustment for Semantic Segmentation
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作者 Hailong Wang Minglei Duan +1 位作者 Lu Yao Hao Li 《Computers, Materials & Continua》 2026年第3期1071-1091,共21页
In image analysis,high-precision semantic segmentation predominantly relies on supervised learning.Despite significant advancements driven by deep learning techniques,challenges such as class imbalance and dynamic per... In image analysis,high-precision semantic segmentation predominantly relies on supervised learning.Despite significant advancements driven by deep learning techniques,challenges such as class imbalance and dynamic performance evaluation persist.Traditional weighting methods,often based on pre-statistical class counting,tend to overemphasize certain classes while neglecting others,particularly rare sample categories.Approaches like focal loss and other rare-sample segmentation techniques introduce multiple hyperparameters that require manual tuning,leading to increased experimental costs due to their instability.This paper proposes a novel CAWASeg framework to address these limitations.Our approach leverages Grad-CAM technology to generate class activation maps,identifying key feature regions that the model focuses on during decision-making.We introduce a Comprehensive Segmentation Performance Score(CSPS)to dynamically evaluate model performance by converting these activation maps into pseudo mask and comparing them with Ground Truth.Additionally,we design two adaptive weights for each class:a Basic Weight(BW)and a Ratio Weight(RW),which the model adjusts during training based on real-time feedback.Extensive experiments on the COCO-Stuff,CityScapes,and ADE20k datasets demonstrate that our CAWASeg framework significantly improves segmentation performance for rare sample categories while enhancing overall segmentation accuracy.The proposed method offers a robust and efficient solution for addressing class imbalance in semantic segmentation tasks. 展开更多
关键词 Semantic segmentation class activation graph adaptive weight adjustment pseudo mask
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Interpersonal adjustment and depression in college students: The mediating effect of core self-evaluation and moderating effect of gender
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作者 Siqi Ma Pei Zhang 《Journal of Psychology in Africa》 2025年第1期135-141,共7页
This study aimed to explore how core self-evaluations and gender influence interpersonal adjustment and depression risk.Participants were 1748 college students(female=59.73%,male=40.27%,mean age=18.71 years,SD=0.78 yea... This study aimed to explore how core self-evaluations and gender influence interpersonal adjustment and depression risk.Participants were 1748 college students(female=59.73%,male=40.27%,mean age=18.71 years,SD=0.78 years).The students completed the Interpersonal Adjustment Scale for College Students,Center for Epidemiological Studies Depression Scale,and Core Self-evaluation Scale.The results of Linear regression and mediated moderated effects modeling revealed that college students with higher interpersonal adjustment and core self-evaluation scores were at lower risk for depression.Core self-evaluation mediated the relationship between interpersonal adjustment and depression in college students for lower risk for depression.Gender moderated the relationship between interpersonal adjustment and core self-evaluation in college students for higher risk for depression in female students.From thesefindings,we conclude that interpersonal adjustment and core self-evaluation are significant for screening depression risk college students.Moreover,female students may benefit from targeted interventions aimed at their interpersonal adjustment for reducing their risk of depression. 展开更多
关键词 college students DEPRESSION interpersonal adjustment core self-evaluation GENDER
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Underwater image enhancement by double compensation with comparative adjustment or edge reinforcement
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作者 ZHAO Xichao LIU Hao 《Optoelectronics Letters》 2025年第12期737-744,共8页
The phenomenon of attenuation and scattering of light propagating in water leads to such problems as color deviation and blur in underwater imaging.These problems bring great challenges to the subsequent feature match... The phenomenon of attenuation and scattering of light propagating in water leads to such problems as color deviation and blur in underwater imaging.These problems bring great challenges to the subsequent feature matching,target recognition and other tasks.Therefore,this paper proposes an underwater image enhancement method by double compensation with comparative adjustment or edge reinforcement.The experiments have found that the proposed method has good underwater color image quality evaluation(UCIQE)value,underwater image quality measures(UIQM)value,and the number of feature matching points.This demonstrates that the proposed method has good color correction ability for underwater images with different attenuation levels,where the processed images have more details suitable for feature matching. 展开更多
关键词 comparative adjustment double compensation underwater imagingthese underwater image enhancement feature matchingtarget recognition color deviation edge reinforcementthe attenuation scattering
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Psychological adjustment differences in ovarian cancer patients receiving different treatment modalities and their clinical significance
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作者 Ya-Lin Wang Yin He +1 位作者 Quan-Hui Luo Ke Huang 《World Journal of Psychiatry》 2025年第12期243-254,共12页
BACKGROUND Ovarian cancer patients often face complex treatment processes and psychological challenges,with different treatment modalities potentially affecting patients’psychological adjustment abilities.AIM To expl... BACKGROUND Ovarian cancer patients often face complex treatment processes and psychological challenges,with different treatment modalities potentially affecting patients’psychological adjustment abilities.AIM To explore the differences in psychological adjustment patterns among ovarian cancer patients receiving surgery,chemotherapy,targeted therapy,and combined therapy,and to analyze their relationship with clinical outcomes.METHODS A retrospective analysis was conducted on the clinical data of 286 ovarian cancer patients who received different treatment modalities from January 2020 to December 2023.Patients were divided into surgery group(n=78),chemotherapy group(n=65),targeted therapy group(n=61),and combined therapy group(n=82).The Self-Rating Anxiety Scale,Self-Rating Depression Scale,and Psychological Adjustment to Cancer Scale were used to assess psychological status,while quality of life,treatment adherence,and two-year survival rate data were collected.Some patients(n=76)received systematic psychological intervention,and the intervention effects were evaluated.RESULTS Patients in the combined therapy group had significantly higher Self-Rating Anxiety Scale(56.3±7.2)and Self-Rating Depression Scale(58.4±6.9)scores than other groups,with the highest incidence of anxiety(58.5%)and depression(62.2%);the targeted therapy group scored highest in the positive coping dimension(28.5±3.6)and had the lowest incidence of anxiety and depression(29.5%/31.1%).Logistic regression analysis showed that positive coping(odds ratio=2.86,95%confidence interval:1.75-4.68)and utilization of social support(odds ratio=2.13,95%confidence interval:1.42-3.56)were protective factors for good treatment adherence.Longitudinal assessment showed that although all patients experienced increased anxiety and depression symptoms at 3 months of treatment,the targeted therapy group and surgery group showed significant improvement at 6 months(P<0.05),while the combined therapy group showed no significant improvement.Psychological intervention effectively improved patients’treatment adherence(by 22.7%)and quality of life(by 15.6 points),with the best effect in the combined therapy group(anxiety incidence decreased by 30.5%,P<0.001).CONCLUSION Different treatment modalities significantly affect the psychological adjustment abilities of ovarian cancer patients,with combined therapy patients facing greater psychological challenges,while targeted therapy patients exhibit healthier psychological adjustment patterns. 展开更多
关键词 Ovarian cancer Treatment modality Psychological adjustment Treatment adherence Psychological intervention
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Design and Performance Analysis of a Small-Sized Underwater Glider with Integrated Buoyancy-Driven and Attitude Adjustment Mechanism
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作者 WANG Hai-quan FAN Shuang-shuang +5 位作者 WANG Tian-lin LI Peng-hao MI De-yuan YANG Shuo ZHANG Shi-he BA Jin-xing 《China Ocean Engineering》 2025年第6期985-1000,共16页
Underwater Gliders(UGs)have emerged as vital instruments in marine research,offering distinct advantages including low operational costs,extended range capabilities,and superior durability.Traditional UGs,however,face... Underwater Gliders(UGs)have emerged as vital instruments in marine research,offering distinct advantages including low operational costs,extended range capabilities,and superior durability.Traditional UGs,however,face limitations due to their substantial size,weight,cost,and deployment complexity.Moreover,the conventional oil pump method for buoyancy adjustment exhibits slow response times,resulting in increased unsteady gliding depth ratios.These constraints limit their application in shallow water environments such as ports,coastal waters,and inland water bodies.This paper presents the TL-200,a small-sized underwater glider that incorporates an integrated buoyancy-driven and attitude adjustment mechanism.Through the implementation of an innovative buoyancy drive unit,the TL-200 achieves enhanced buoyancy regulation response while maintaining a simplified structure compared to conventional gliders.A dynamic model for the TL-200 was developed and validated through comparative analysis of numerical results and experimental data.Utilizing this dynamic model,motion simulations were conducted to examine the influence of metacentric height on motion parameters.Additionally,the study evaluated the gliding efficiency and energy consumption of the TL-200 under varying buoyancy adjustments.The findings demonstrate the effectiveness of this small-sized underwater glider's integrated buoyancy-driven and attitude adjustment mechanism. 展开更多
关键词 underwater glider buoyancy-driven attitude adjustment dynamic model motion performance analysis
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Adjustment of thalweg longitudinal profiles in response to sediment silting in cascade reservoirs:A case study of the lower Jinsha River
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作者 WANG Suiji 《Journal of Geographical Sciences》 2025年第7期1497-1515,共19页
How the strong segmentation of cascade reservoir dams and the spatiotemporal changes of sediment retention volume affect the river morphology adjustment in the reservoir area is a scientific issue worthy of exploratio... How the strong segmentation of cascade reservoir dams and the spatiotemporal changes of sediment retention volume affect the river morphology adjustment in the reservoir area is a scientific issue worthy of exploration.This study aims to reveal the adjustment mechanism of the thalweg longitudinal profile of cascade reservoirs.This study focuses on the Xiangjiaba and Xiluodu reservoirs located in the lower reaches of the Jinsha River.Utilizing multi-period observational data of thalweg elevation in reservoir reaches both before and after dam construction,the research employs statistical,geomorphological,and sedimentological methodologies to analyze variation characteristics in the measured curves,trend curves,and theoretical fitting curves of the thalweg longitudinal profile.The investigation ultimately reveals two distinct adjustment patterns in the longitudinal profiles of these cascade reservoirs:the concave curve type and the convex curve type.The former is characterized by weak riverbed scouring and silting changed to rapid aggradation in the upstream section of the reservoir area after dam closure,then changed to slow aggradation in the whole reservoir area,which is the common feature of reservoirs that were built earlier and are relatively located in the downstream(such as the Xiangjiaba Reservoir).The latter is characterized by a straight line or concave curve type with weak riverbed scouring and silting before the dam closure changed to a convex curve type with strong siltation after dam closure,which is the characteristic of reservoirs that were built later and are relatively located in the upstream(such as the Xiluodu Reservoir).The adjustment of the cascade reservoir longitudinal profile is controlled by the spatiotemporal changes of the sediment deposition volume and sedimentation rate in the reservoir area,and the alternating changes of the hydrodynamic gradient and regulation mode affect the spatial heterogeneity of the sedimentation rate.The research results are helpful for understanding the adjustment mechanism of the cascade reservoir longitudinal profile in similar areas and have a guiding role in predicting the adjustment trend of the cascade reservoir longitudinal profile without observation data. 展开更多
关键词 cascade reservoirs longitudinal profile adjustment pattern sediment silting lower Jinsha River
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Dynamic interpretation of stress adjustment types in high geostress hard rock tunnels based on microseismic monitoring
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作者 Weihao Xu Chunchi Ma +4 位作者 Tianbin Li Shoudong Shi Feng Peng Ziquan Chen Hang Zhang 《International Journal of Mining Science and Technology》 2025年第5期801-816,共16页
Dynamic stress adjustment in deep-buried high geostress hard rock tunnels frequently triggers catastrophic failures such as rockbursts and collapses.While a comprehensive understanding of this process is critical for ... Dynamic stress adjustment in deep-buried high geostress hard rock tunnels frequently triggers catastrophic failures such as rockbursts and collapses.While a comprehensive understanding of this process is critical for evaluating surrounding rock stability,its dynamic evolution are often overlooked in engineering practice.This study systematically summarizes a novel classification framework for stress adjustment types—stabilizing(two-zoned),shallow failure(three-zoned),and deep failure(four-zoned)—characterized by distinct stress adjustment stages.A dynamic interpretation technology system is developed based on microseismic monitoring,integrating key microseismic parameters(energy index EI,apparent stressσa,microseismic activity S),seismic source parameter space clustering,and microseismic paths.This approach enables precise identification of evolutionary stages,stress adjustment types,and failure precursors,thereby elucidating the intrinsic linkage between geomechanical processes(stress redistribution)and failure risks.The study establishes criteria and procedures for identifying stress adjustment types and their associated failure risks,which were successfully applied in the Grand Canyon Tunnel of the E-han Highway to detect 50 instances of disaster risks.The findings offer invaluable insights into understanding the evolution process of stress adjustment and pinpointing the disaster risks linked to hard rock in comparable high geostress tunnels. 展开更多
关键词 High geostress tunnels Stress adjustment types Microseismic monitoring Dynamic interpretation Risk identification
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Parental autonomy support effects on children’s school adjustment:The longitudinal mediating effect of executive function
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作者 Xia Hu Zhu Li +1 位作者 Yawen Shi Xiaopei Xing 《Journal of Psychology in Africa》 2025年第4期471-480,共10页
This longitudinal study examined the association between parental autonomy support and school-aged children’s adjustment across four major domains of school functioning,as well as the mediating role of children’s ex... This longitudinal study examined the association between parental autonomy support and school-aged children’s adjustment across four major domains of school functioning,as well as the mediating role of children’s executive function.Participants were 476 school-aged children(girl:49.2%,M_(age)=10.49 years,SD=1.32 years),who completed the Psychological Autonomy Support Scale,the Behavior Rating Inventory of Executive Function–2,and the Primary School Students’Psychological Suzhi Scale at baseline and at two subsequent follow-up assessments.Results from unconditional latent growth curve models and structural equation modeling indicated that paternal autonomy support was a significant predictor of children’s adjustment across all four school domains.In contrast,maternal autonomy support was significantly associated only with interpersonal adjustment.Both the intercept(initial level)and slope(rate of change)of children’s executive function significantly predicted their adjustment in all four domains.Notably,the initial level of executive function fully mediated the association between paternal autonomy support and school adjustment,whereas the rate of change in executive function did not serve as a significant mediator.Thesefindings underscore the importance of promoting parental autonomy-supportive behaviors-particularly among fathers-as a means to enhance children’s executive functioning and,consequently,their school adjustment. 展开更多
关键词 parental autonomy support executive function school adjustment longitudinal mediation
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Active Precision Adjustment Mechanism for Large Space Reflectors
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作者 Haitao Wang Bo Li Yi Yang 《Chinese Journal of Mechanical Engineering》 2025年第4期447-465,共19页
The demand for high-precision large-aperture antennas has continued to increase owing to the expanding application of spaceborne deployable active phased array antennas in remote sensing observation,satellite communic... The demand for high-precision large-aperture antennas has continued to increase owing to the expanding application of spaceborne deployable active phased array antennas in remote sensing observation,satellite communication,navigation positioning,and deep space exploration.However,deployment errors in deployable mechanisms,particularly hinge-induced deflection errors during array surface deployment,degrade on-orbit surface accuracy.This study proposes an active adjustment strategy that installs compliant parallel mechanisms on the backplane of antenna subarrays to regulate surface splicing precision.For one-dimensional(1D)deployable antennas,a two-translation one-rotation(2T1R)parallel mechanism configuration is employed for precision adjustment,whereas two-dimensional(2D)deployable antennas adopt a one-translation two-rotation(1T2R)configuration.A reconfigurable parallel mechanism architecture satisfying space deployment constraints-the 3PSS-2RPU-UPR/RPU parallel mechanism-is designed via configuration synthesis.The degrees of freedom(DOF)are verified via the screw theory,with complete inverse kinematics solutions derived.Search algorithms further quantify the adjustment workspace while clarifying the coupling relationships between DOFs.Equivalent compliant parallel mechanism models are obtained using the rigid-body replacement method,followed by a compliance analysis and motion simulation of compliant joints(notched flexure hinges and leaf-spring flexure prismatic joints).A systematic investigation of the deformation characteristics under different actuation modes confirmed the validity of the equivalent models.Ground experiments demonstrated close agreement between the measured and simulated adjustments,with open-loop adjustment errors constituting less than 10%of the adjustment range,thereby validating the feasibility of the method.The precision adjustment mechanism achieved configuration switching(2T1R/1T2R)through an inverted central limb design,integrating dual-mode compensation into a reconfigurable system. 展开更多
关键词 Precision adjustment mechanism Screw theory Compliant parallel mechanism Compliance analysis
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Photovoltaic Power Prediction Cosidering Mode Switching and Parallel Weight Adjustment
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作者 Penghui Liu Tianyu Yang +1 位作者 Peng Zhang Peiyuan Zou 《Energy Engineering》 2025年第4期1387-1402,共16页
The photovoltaic(PV)output process is inherently complex,often disrupted by a multitude of meteoro-logical factors,while conventional detection methods at PV power stations prove inadequate,compromising prediction acc... The photovoltaic(PV)output process is inherently complex,often disrupted by a multitude of meteoro-logical factors,while conventional detection methods at PV power stations prove inadequate,compromising prediction accuracy.To address this challenge,this paper introduces a power prediction method that leverages modal switching(MS),weight factor adjustment(WFA),and parallel long short-term memory(PALSTM).Initially,historical PV power station data is categorized into distinct modes based on global horizontal irradiance and converted solar angles.Correlation analysis is then employed to evaluate the impact of various meteorological factors on PV power,selecting those with strong correlations for each specific mode.Subsequently,the weights of meteorological parameters are optimized and adjusted,and a PALSTM neural network is constructed,with its parallel modal parameters refined through training.Depending on the prediction time and input data mode characteristics,the appropriate mode channel is selected to forecast PV power station generation.Ultimately,the feasibility of this method is validated through an illustrative analysis of measured data from an Australian PV power station.Comparative test results underscore the method’s advantages,particularly in scenarios where existing detection methods are lacking and meteorological factors frequently fluctuate,demonstrating its superior prediction accuracy and stability. 展开更多
关键词 Ultra short-term power prediction mode switching weight factor adjustment parallel neural network
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A tunable acoustic metasurface via one-dimensional mechanical adjustment for real-time focusing
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作者 Jie Hu Mengqi Jiang +1 位作者 Rui Zang Yuhang Qian 《Chinese Physics B》 2025年第10期399-404,共6页
Adjustable or programmable metamaterials offer versatile functions,while the complex multi-dimensional regulation increases workload,and hinders their applications in practical scenarios.To address these challenges,we... Adjustable or programmable metamaterials offer versatile functions,while the complex multi-dimensional regulation increases workload,and hinders their applications in practical scenarios.To address these challenges,we present a mechanically programmable acoustic metamaterial for real-time focal tuning via one-dimensional phase-gradient modulation in this paper.The device integrates a phase gradient structure with concave cavity channels and an x-shaped telescopic mechanical framework,enabling dynamic adjustment of inter-unit spacing(1 mm-3 mm)through a microcontroller-driven motor.By modulating the spacing between adjacent channels,the phase gradient is precisely controlled,allowing continuous focal shift from 50 mm to 300 mm along the x-axis at 7500 Hz.Broadband focusing is also discussed in the range6800 Hz-8100 Hz,with transmission coefficients exceeding 0.5,ensuring high efficiency and robust performance.Experimental results align closely with simulations,validating the design's effectiveness and adaptability.Unlike conventional programmable metamaterials requiring multi-dimensional parameter optimization,this approach simplifies real-time control through single-axis mechanical adjustment,significantly reducing operational complexity.Due to the advantages of broadband focusing,simple control mode,real-time monitoring,and so on,the device may have extensive applications in the fields of acoustic imaging,nondestructive testing,ultrasound medical treatment,etc. 展开更多
关键词 phase gradient structure one-dimensional mechanical adjustment adjustable focusing
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基于高精度三维扫描的钢梁智能调位一体化控制技术研究及应用
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作者 王敏 黄涛 樊健生 《桥梁建设》 北大核心 2026年第1期155-161,共7页
为提高装配式钢桥节段钢梁顶推施工焊接前调位精度与效率,提出基于高精度三维扫描的钢梁智能调位一体化控制技术。该技术从减小钢梁调位误差的角度出发,基于三维扫描技术得到高精度点云数据,采用表面重建算法得到带制造误差的带力模型,... 为提高装配式钢桥节段钢梁顶推施工焊接前调位精度与效率,提出基于高精度三维扫描的钢梁智能调位一体化控制技术。该技术从减小钢梁调位误差的角度出发,基于三维扫描技术得到高精度点云数据,采用表面重建算法得到带制造误差的带力模型,模拟钢梁“预拼-调位-拼装”全过程挠度变化,计算得到由制造误差、环境温度变化、支撑条件改变等带来的调位误差,修正调位指令,以减小系统误差;提出以最优化法为核心的智能调位算法,建立梁面测点数据与梁底三向千斤顶调整量的微分运动关系,采用智能调位系统取代人工进行控制点坐标采集和调位控制操作,以减小调位过程中的人为操作误差。为验证该技术的可行性,依托某黄河特大桥进行实际应用。结果表明:采用该智能调位一体化控制技术,焊接面匹配精度为±1 mm,可在5 min内将调位误差控制在±2 mm,较传统方法,该技术不仅提高了施工效率及调位精度,同时提高了焊接平顺度。 展开更多
关键词 装配式钢桥 节段钢梁 顶推施工 三维扫描 带力模型 智能调位系统 钢梁调位
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二维调节式太阳观测系统变形误差在轨辨识与补偿
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作者 王皓 许海玉 +3 位作者 王田野 边志强 闫奎 张立昌 《空间科学学报》 北大核心 2026年第1期142-149,共8页
针对卫星二维调节式太阳观测系统内部变形误差导致的光轴指向偏差问题,提出了一种变形误差在轨辨识与补偿方法.对太阳观测系统内部光路传递过程进行了数学建模,对数学模型中的变形误差参数给出在轨辨识与补偿方法,通过引入高精度数字太... 针对卫星二维调节式太阳观测系统内部变形误差导致的光轴指向偏差问题,提出了一种变形误差在轨辨识与补偿方法.对太阳观测系统内部光路传递过程进行了数学建模,对数学模型中的变形误差参数给出在轨辨识与补偿方法,通过引入高精度数字太敏分步辨识的方式,解决了利用太阳观测成像结果无法直接解算全部变形误差参数的问题,通过数学仿真对辨识与补偿方法进行模拟,并以光轴指向精度作为评价标准对补偿效果进行了评估.仿真结果表明,变形误差在轨补偿前后,太阳观测载荷光轴指向精度提升了两个数量级.验证了本文提出方法的有效性.研究结果可为其他含有二维调节机构的有效载荷提供参考. 展开更多
关键词 太阳观测 变形误差 在轨辨识与补偿 二维调节机构
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五个牡丹品种的抗寒性评价
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作者 王卫成 任家玄 +2 位作者 潘艳花 汤玲 黄蓉 《北方园艺》 北大核心 2026年第4期61-69,共9页
以5个牡丹品种(‘彩楼子’‘大藕’‘佛头青’‘黄冠’‘星光溢彩’)为试材,采用人工模拟低温胁迫(-35~-15℃)的方法,研究了5个品种在处理后相对电导率、半致死温度(LT_(50))、丙二醛(MDA)、脯氨酸(Pro)、可溶性糖、可溶性蛋白质含量及... 以5个牡丹品种(‘彩楼子’‘大藕’‘佛头青’‘黄冠’‘星光溢彩’)为试材,采用人工模拟低温胁迫(-35~-15℃)的方法,研究了5个品种在处理后相对电导率、半致死温度(LT_(50))、丙二醛(MDA)、脯氨酸(Pro)、可溶性糖、可溶性蛋白质含量及超氧化物歧化酶(SOD)、过氧化物酶(POD)活性的变化,并采用隶属函数法综合评价其抗寒性,以期为牡丹抗寒品种选育及区域化栽培提供参考依据。结果表明:‘星光溢彩’牡丹的LT_(50)最低,相对电导率在-35℃时增幅最小,MDA含量在-25℃处理后下降,细胞膜稳定性最强,可溶性糖含量和SOD活性在-30℃时最高,有效清除了ROS对细胞的伤害。‘黄冠’牡丹的LT_(50)为-20.069℃,-35℃处理时电导率为72.80%,膜损伤程度中等。在-35℃处理时可溶性蛋白质含量和SOD活性均达最大值,显著高于其他品种,但POD活性在-25℃降至最低值(3.586 U·min^(-1)·g^(-1)),导致细胞内ROS积累。‘佛头青’牡丹的LT_(50)最高,-35℃处理时相对电导率达74.29%,膜损伤最严重。MDA含量和POD活性随着处理温度的降低大致呈降低的趋势,且POD活性在-20℃时显著低于其他处理。隶属函数分析显示,‘星光溢彩’牡丹抗寒性最强,‘佛头青’牡丹抗寒性最弱。结合LT_(50)和隶属函数评价显示,5个牡丹品种的抗寒力大小为‘星光溢彩’>‘彩楼子’>‘黄冠’>‘大藕’>‘佛头青’,以上品种通过增强细胞膜稳定性、积累渗透调节物质以及激活抗氧化系统来提高抗寒性。 展开更多
关键词 牡丹 抗寒性 半致死温度 渗透调节 隶属函数
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中间品进口、进口价格与中国企业就业规模
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作者 魏浩 卢紫薇 李明珝 《国际贸易》 北大核心 2026年第1期71-84,共14页
基于中国工业企业数据和中国海关进出口数据,本文实证分析了中间品进口价格变化对企业就业规模的影响。研究发现:(1)从整体上来看,中间品进口总价格对企业就业规模的影响不显著,进一步将总价格分解为质量价格和非质量价格后发现,中间品... 基于中国工业企业数据和中国海关进出口数据,本文实证分析了中间品进口价格变化对企业就业规模的影响。研究发现:(1)从整体上来看,中间品进口总价格对企业就业规模的影响不显著,进一步将总价格分解为质量价格和非质量价格后发现,中间品进口质量价格上升显著促进了企业就业,而中间品进口非质量价格上升则对企业就业产生了显著的抑制作用;(2)产出规模扩张、创新投入增加和生产率变动是中间品进口价格影响企业就业的重要渠道,并且质量价格和非质量价格变动在各渠道中产生了方向相反的作用;(3)中间品进口质量价格和非质量价格的就业效应在不同类型企业中表现出显著的异质性。本文的政策启示是,要科学看待进口价格变化,客观认知中间品进口质量价格上升的积极影响,高度重视中间品进口非质量价格上升的负面影响,着眼统筹发展和安全,加快保障进口安全。 展开更多
关键词 中间品进口 进口价格 进口质量价格 进口非质量价格 企业就业规模
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Spinal stenosis treated with acupuncture on Huátuó Jiájǐ(夹脊EX-B 2) and vertebral curvature adjustment:report of therapeutic effect on 189 cases 被引量:4
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作者 韦以宗 王秀光 +4 位作者 戴国文 田新宇 潘东华 韦春德 高腾 《World Journal of Acupuncture-Moxibustion》 2009年第1期22-29,34,共9页
Objective To observe the clinical effects on spinal stenosis treated with acupuncture on Huatuo Jiaji (夹脊EX-B 2) and vertebral curvature adjustment. Methods Comprehensive therapy was applied to all of 189 cases of... Objective To observe the clinical effects on spinal stenosis treated with acupuncture on Huatuo Jiaji (夹脊EX-B 2) and vertebral curvature adjustment. Methods Comprehensive therapy was applied to all of 189 cases of any type of spinal stenosis, in which gukong needling technique was applied to Huatuo Jiaji (夹脊EX-B 2) at C4 - T5 and T12 - L5, associated with vertebral curvature adjustment with traction. The therapeutic effects were observed. Results Total effective rate was 96.8%, in which, clinical cured rate was 31.7% and excellent and good rate was 89.9% in average 28-month fol- low-up visit. Conclusion Spinal stenosis is segmental dynamic stenosis. It can be cured by acupuncture on Huatuo Jiaji (夹脊EX-B 2) and vertebral curvature adjustment and satisfactory result is achieved. 展开更多
关键词 Huatuo Jiaji (夹脊EX-B 2) gukong Needling Four Dimensional Suspension Traction Vertebral Curvature adjustment Spinal Stenosis
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飞行器旋转重入变形超结构骨架力学特性分析
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作者 杨慧 刘瀚孺 +2 位作者 王岩 杨彦飞 肖洪 《国防科技大学学报》 北大核心 2026年第1期262-273,共12页
空天飞行器变形翼在后掠、变弯度和扭转变形时需要骨架机构实现大变形,为此提出一种具有可调弹性参数的旋转重入超结构。旋转重入超结构由内凹八边形旋转90°及外伸韧带构成,通过外伸直臂韧带的空间拓扑填充策略构建翼型截面,形成... 空天飞行器变形翼在后掠、变弯度和扭转变形时需要骨架机构实现大变形,为此提出一种具有可调弹性参数的旋转重入超结构。旋转重入超结构由内凹八边形旋转90°及外伸韧带构成,通过外伸直臂韧带的空间拓扑填充策略构建翼型截面,形成具备变形能力的骨架构型。基于莫尔理论建立旋转重入超结构沿空间三方向的弹性模量、泊松比的理论模型。用ANSYS软件构建旋转重入变形结构的有限元模型,3D打印加工5个旋转重入变形结构的样机。将理论、仿真与实验结果分别进行对比,沿x、y和z向的泊松比最大相对误差绝对值为10.22%,由此表明理论模型和仿真模型的准确性。分析几何参数对超结构弹性参数影响,发现长宽比和结构角度对泊松比力学参数影响较大,该研究可为空天飞行器变形翼骨架应用提供理论基础。 展开更多
关键词 飞行器 变形翼 超结构 力学特性 泊松比 刚度可调节
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Effect of Osmotic Stress with PEG6000 on Osmotic Adjustment Solute in Seedling Leaves of Chenopodium album L. 被引量:4
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作者 孙存华 李扬 +5 位作者 贺鸿雁 杜伟 金会丽 王东升 陈湘玲 徐新娜 《Agricultural Science & Technology》 CAS 2007年第3期20-24,共5页
[ Objective] The purpose was to discuss drought resistance mechanism of Chenopodium album L. and supply theoretical basis and practical guidance for artificial cultivation and popularization of C. album. [ Method] C. ... [ Objective] The purpose was to discuss drought resistance mechanism of Chenopodium album L. and supply theoretical basis and practical guidance for artificial cultivation and popularization of C. album. [ Method] C. album seedlings grown to 6th leaf stage were conducted osmotic stress treatment with PEG6000 osmotic whose concentration was set up as 0, 5%, 10% and 20% and the various physiological indices of the 3rd -5th function leaves in upper plant were determined after being treated for 0, 1,3, 5, 7 and 9 d. [ Result] Under osmotic stress with 5% PGE, the relative water content (RWC) of C. album reduced less. Under osmotic stress with 10%, the RWC in seedling leaves of C. album decreased to 62% on the fifth day and the leaves began to wither. Under osmotic stress with 20%, the RWC in seedling leaves of C. album decreased to 61.9% on the third day and the leaves appeared withering, and the RWC decreased to 48.6% on the 7th day and the leaves were dry and yellow. Proline contents in seedling leaves of C. album under osmotic stress with 5%, 10% and 20% PEG were 7.64, 10.9 and 29.4 times of CK on the 7th day. [ Conclusion] C. album hed some adaptability to moderate osmotic stress, but the PEG osmotic stress with high concentration and long time might lead to severe damage on C. album. 展开更多
关键词 Chenopodium album L. PEG Osmotic stress Osmotic adjustment solute
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农用四履带移动平台底盘设计与试验
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作者 漆海霞 容健辉 +2 位作者 陈宇 王朝海 刘厚诚 《中国农机化学报》 北大核心 2026年第2期240-248,共9页
为解决轮式移动平台在泥泞地面通过性不足以及双履带式底盘在越障过程中因重心不稳易导致设备受损的问题,设计一种新型农用四履带移动平台底盘。该底盘兼具轮式底盘在平坦道路行驶时的灵活性,以及双履带底盘在复杂地形下的稳定越障与高... 为解决轮式移动平台在泥泞地面通过性不足以及双履带式底盘在越障过程中因重心不稳易导致设备受损的问题,设计一种新型农用四履带移动平台底盘。该底盘兼具轮式底盘在平坦道路行驶时的灵活性,以及双履带底盘在复杂地形下的稳定越障与高承载性能。底盘采用四履带行走机构,并配置可调宽装置,调节范围可达350 mm,可根据温室与大田的作业需求灵活调整宽度,从而有效提升平台对不同环境的适应性。建立四履带移动平台的越障动力学模型,对二阶段与四阶段越障过程开展受力分析;利用SolidWorks进行三维建模,并将模型导入RecurDyn平台开展多因素正交试验与多元回归分析,得到越障驱动力回归方程R2为0.915,并在此基础上确定实机结构参数。组装实机并进行速度、转向性能和越障能力试验。试验结果表明,该移动底盘根据调宽不同,转弯半径范围为588.6~735.6 mm;可顺利翻越最大高度为171 mm的垂直障碍物,且驱动力实测值与仿真值误差小于6%;速度测试结果合格。该农用四履带移动平台底盘兼具灵活性与通过性,能够满足温室与大田的作业需求,为农业信息监测设备的稳定搭载和自动化应用提供可靠支撑。 展开更多
关键词 四履带移动平台底盘 越障 可调宽装置 温室与大田
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