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Association between serum 25(OH)D levels and cancer in adults with psoriasis:A cross-sectional study 被引量:1
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作者 Lingquan Deng Yamei Gao +1 位作者 Chenxingyue Zhang Zhiqiang Yin 《Journal of Biomedical Research》 2026年第2期224-226,共3页
Dear Editor,Psoriasis,a chronic inflammatory cutaneous condition,is characterized by the development of red plaques with silvery scales,significantly affecting patients'quality of life and mental health[1].This co... Dear Editor,Psoriasis,a chronic inflammatory cutaneous condition,is characterized by the development of red plaques with silvery scales,significantly affecting patients'quality of life and mental health[1].This condition is thought to affect approximately 2%of the Western population,with diagnosis peaking in early adulthood[2].Vitamin D,a fat-soluble vitamin,is essential for phospho-calcium metabolism,calcium homeostasis,and bone health. 展开更多
关键词 serum oh d levels CANCER cross sectional study inflammatory cutaneous conditionis PSORIASIS ADULTS
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英国A Level考试制度的演进脉络及其对我国高考改革的镜鉴
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作者 温军英 《宁波大学学报(教育科学版)》 2026年第1期122-132,共11页
A Level考试素有“英国高考”之称。其制度演进大致经历了发轫与探索、扩张与调适、回归与重塑三个阶段,其主要变革内容包括四个方面:组织形式从年终末考的线性考试模式发展为一年多考的模块化考试,再回归线性考试模式;考试评价从常模... A Level考试素有“英国高考”之称。其制度演进大致经历了发轫与探索、扩张与调适、回归与重塑三个阶段,其主要变革内容包括四个方面:组织形式从年终末考的线性考试模式发展为一年多考的模块化考试,再回归线性考试模式;考试评价从常模参照转变为标准参照,评价手段逐步优化;考试要求从注重学科深度转变为强调知识广度,再发展为追求广度和深度并重;考试内容从偏重学术性转变为普职并重,再发展为职普融通和强调基础学科。变革的动因既有来自外部的国际竞争加剧和国内政党轮替,也有来自内部的文化价值观驱动和考试选才效度追求。A Level考试制度对我国高考改革有一定启发,我国可结合国情,以基础学科为支点、职普融通为路径、多样化的考试选择为依托、预测效度为导向,开展本土化探索。 展开更多
关键词 A level 高考 考试 选科 高校招生
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Sea level rise in the Baltic Sea:Data from Estonian coastal tide gauges over 30 years
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作者 Ivar Kapsi Tarmo Kall Aive Liibusk 《Geodesy and Geodynamics》 2026年第2期267-279,共13页
This study investigates the rate of sea level rise along the Estonian coastline of the Baltic Sea over the three decades(1993-2022)using tide gauge data and advanced analytical methods.Tide gauge data were analyzed us... This study investigates the rate of sea level rise along the Estonian coastline of the Baltic Sea over the three decades(1993-2022)using tide gauge data and advanced analytical methods.Tide gauge data were analyzed using an open-source software based on the"TG Analysis"method developed by Kristian Breili.The results reveal significant spatial and temporal variability:the average relative sea level rise was 1.35±1.91 mm/yr over the three decades,with a notable acceleration to 9.01±8.67 mm/yr in the last decade(2013-2022).Absolute sea level rise,after correction for land uplift(NKG2016LU),averaged4.16±1.81 mm/yr.Regional differences were observed,with faster relative sea level rise in areas of slower land uplift(e.g.,P??rnu,Virtsu)and vice versa.The data and trends were further analyzed by applying advanced analytical methods(differentiation,spectral and segmented regression analysis,and sea level model validation).By differentiating the sea level rise trends along the Estonian coast,and comparing tide gauge data with data from Stockholm and Hanko,the results show a minimal velocity difference(0.65 mm/yr),confirming the reliability of the trends.Spectral analysis and segmented regression analysis identified breakpoints mainly in the early 1990s,with the transition to automated tide gauges in 2010 having no significant impact.Validation of the ESA BalticSEAL model showed good performance in western Estonia,while larger discrepancies were observed in the northern regions,which are linked to local geophysical factor. 展开更多
关键词 Sea level rise Baltic Sea Tide gauge Sea level model Land uplift
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Strategies of allocating root-shoot biomass in plantations and natural forests at various community stages and moisture levels
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作者 Wenjing Chen Lei Liu +3 位作者 Josep Penuelas Guoyi Zhou Langqin Hua Zhurong Wu 《Journal of Forestry Research》 2026年第2期85-99,共15页
The root-to-shoot(R/S)ratio is a critical indicator of the balance between root biomass and shoot biomass,representing the ecological strategies and adaptive responses of plants to environmental conditions.However,the... The root-to-shoot(R/S)ratio is a critical indicator of the balance between root biomass and shoot biomass,representing the ecological strategies and adaptive responses of plants to environmental conditions.However,the patterns of change in community R/S ratios during forest succession and their response to moisture levels across broad geographic gradients remains unclear.Based on forest biomass data from a national field inventory of 5,825 plots conducted across China between 2011 and 2015,this study looked into allocating biomass shoots and roots at the early,middle,and late stages of growth in plantations and succession in natural forests,and evaluated how moisture availability influences this allocation.The results revealed a significant decline in R/S ratios from early to late stages for both plantations and natural forests.Shoot and root biomass in plantations grew isometrically during the early and middle succession stages but shifted to allometric growth in the late stage,with the slope of the log-transformed shoot-root biomass relationship differing significantly across growth stages.Natural forests,in contrast,maintained isometric growth across successional stages,showing no significant variation in the slope of the log-transformed shoot-root biomass relationship.Environmental factors,particularly moisture levels,strongly influenced R/S ratios.Moisture levels significantly affected size-corrected R/S ratios,particularly in the middle stage of plantations and the early and middle stages of natural forests,supporting the hypothesis of optimal allocation.These findings suggest that in water-limited regions,forest management should prioritize drought-tolerant,deep-rooted native species,encourage mixed-species planting in the early stage,and reduce logging intensity in mature plantations.Conserving natural forests to maintain successional dynamics is essential for long-term ecological resilience.These findings emphasize the importance of balancing productivity with ecological sustainability by adapting practices to specific environments and forest types under climate change. 展开更多
关键词 Root-to-shoot ratios Biomass allocation Forest type Community stage Moisture levels Allometric scaling
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Improved expert system of rockburst intensity level prediction based on machine learning and data-driven:Supported by 1114 rockburst cases in 197 rock underground projects
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作者 PANG Hong-li GONG Feng-qiang +1 位作者 GAO Ming-zhong DAI Jin-hao 《Journal of Central South University》 2026年第1期335-356,共22页
Accurate prediction of rockburst intensity levels is crucial for ensuring the safety of deep hard rock engineering construction.This paper introduced an expert system for rockburst intensity level prediction that empl... Accurate prediction of rockburst intensity levels is crucial for ensuring the safety of deep hard rock engineering construction.This paper introduced an expert system for rockburst intensity level prediction that employs machine learning algorithms as the basis for its inference rules.The system comprises four modules:a database,a repository,an inference engine,and an interpreter.A database containing 1114 rockburst cases was used to construct 357 datasets that serve as the repository for the expert system.Additionally,19 types of machine learning algorithms were used to establish 6783 micro-models to construct cognitive rules within the inference engine.By integrating probability theory and marginal analysis,a fuzzy scoring method based on the SoftMax function was developed and applied to the interpreter for rockburst intensity level prediction,effectively restoring the continuity of rockburst characteristics.The research results indicate that ensemble algorithms based on decision trees are more effective in capturing the characteristics of rockburst.Key factors for accurate prediction of rockburst intensity include uniaxial compressive strength,elastic energy index,the maximum principal stress,tangential stress,and their composite indicators.The accuracy of the proposed rockburst intensity level prediction expert system was verified using 20 engineering rockburst cases,with predictions aligning closely with the actual rockburst intensity levels. 展开更多
关键词 rock mechanics ROCKBURST rockburst intensity level prediction expert system machine learning supervised learning
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A Level物理教材内容及试题分析——以“天文宇宙学”为例
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作者 孟庆楠 《中学物理教学参考》 2026年第9期57-59,共3页
基于核心素养分析英国高中A Level物理教材中的天体宇宙学内容,剖析该部分内容的教学目标,以2023年6月考季第10题为例,探讨其试题命制的特点,通过对教材内容的梳理和试题的深入分析,为中学物理教学及试题多样化提供参考。
关键词 核心素养 A level物理教材 天体物理 试题命制
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The characteristics of cerebral cortical oxygenation levels and functional connectivity under upper and lower limb exercise-induced fatigue
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作者 Feng Li Yajie Wang +3 位作者 Xinyi Wang Jiawei Bi Ye Luo Lingyan Huang 《Sports Medicine and Health Science》 2026年第1期61-69,共9页
This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fati... This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fatigue was induced using an upper limb ergometer or a lower limb ergometer,with the load increasing gradually each minute.fNIRS covering the prefrontal cortex and motor cortex were used to collect data during the resting state,both before and after fatigue induction.A two-way ANOVA was conducted to examine differences in oxyhemoglobin(HbO_(2))and functional connectivity before and after fatigue induction in both groups,with the significance level set at 0.05.Exercise-induced fatigue in both the upper and lower limbs leads to a significant decrease in cerebral cortical oxygenation levels.Upper limb fatigue leads to a significant reduction in functional connectivity,there were significant decreases in connectivity within the motor cortex,between the motor cortex and frontal regions,and between the right ventrolateral prefrontal cortex and other frontal regions.Conversely,no significant changes were observed before and after lower limb fatigue.Future studies should focus on examining the extent to which how changes in the cerebral cortex,induced by exercise fatigue,are linked to exercise-and/or performance-related outcomes. 展开更多
关键词 Brain functional connectivity Cerebral oxygenation level Exercise-induced fatigue Functional near-infrared spectroscopy
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Suitable area selection method based on scene matching level segmentation
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作者 Chao YANG Yuanxin YE +3 位作者 Renyuan LIU Chengjia FAN Liang ZHOU Jiwei DENG 《Chinese Journal of Aeronautics》 2026年第2期356-369,共14页
The selection of a suitable navigation area is pivotal in aircraft scene matching guidance technology.This study addresses the challenge of identifying suitable reference image ranges for precise scene matching,which ... The selection of a suitable navigation area is pivotal in aircraft scene matching guidance technology.This study addresses the challenge of identifying suitable reference image ranges for precise scene matching,which is crucial for enhancing aircraft positioning accuracy.Traditional methods for image matchability analysis are often limited by their reliance on manual feature parameter design and threshold-based filtering,resulting in suboptimal accuracy and efficiency.This paper proposes a novel network architecture for selecting suitable navigation areas using image Matching Level Segmentation(MLSNet).The approach involves two key innovations:a method for generating segmentation labels that quantify matchability levels and an end-to-end network architecture for rapid and precise prediction of reference image matchability segmentation maps.The network includes two core modules:the saliency analysis module uses multi-layer convolutional networks to accurately detect image saliency features across various levels and scales;the multidimensional attention module utilizes attention mechanisms to focus on feature channels and spatial neighborhood scenes to assess the image’s matchability.Our method was rigorously tested on an extensive collection of remote sensing images,where it was benchmarked against a range of both traditional and cutting-edge deep learning methods.The findings indicate that MLSNet is significantly superior to traditional methods in accuracy and efficiency of matchability analysis,and is also relatively ahead of state-of-the-art deep learning models. 展开更多
关键词 Deep learning Image matching level segmentation OPTICAL Scene matching navigation Suitable matching area selection
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Homeostasis and failure of mitochondria on the single-cell level
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作者 Kristina Friedland Kristina Endres 《Neural Regeneration Research》 2026年第8期3555-3556,共2页
Mitochondria are the central organelles that allow eukaryotic cells to efficiently convert nutrients into energy for cellular functions such as anabolic reactions,movement,and regulation.A reduction in the number of m... Mitochondria are the central organelles that allow eukaryotic cells to efficiently convert nutrients into energy for cellular functions such as anabolic reactions,movement,and regulation.A reduction in the number of mitochondria or the occurrence of dysfunctional mitochondria leads to serious diseases such as the Leigh syndrome.However,such changes have also been connected to Alzheimer’s disease(AD)and many more diseases of different organ systems and occur during the aging process.Mitochondria are,therefore. 展开更多
关键词 eukaryotic cells HOMEOSTASIS convert nutrients energy organ systems MITOCHONDRIA central organelles anabolic reactionsmovementand single cell level
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Enhancing High-Level Opening Up
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《ChinAfrica》 2026年第3期2-2,共1页
Hainan Province in south China is the country’s second-largest island and the largest free trade port by area.It has entered a historic phase in China’s drive to promote high-level institutional opening up.On 18 Dec... Hainan Province in south China is the country’s second-largest island and the largest free trade port by area.It has entered a historic phase in China’s drive to promote high-level institutional opening up.On 18 December 2025,Hainan officially launched island-wide special customs operations,commonly referred to as“customs closure.”From that date,goods entering or leaving the island,except those traded with the Chinese mainland,are subject to simplified customs procedures and potentially reduced or zero tariffs. 展开更多
关键词 free trade port Hainan Province reduced zero tariff high level opening up simplified customs procedures customs closure institutional opening up
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Heimtextil 2026 sharpened its global market relevance by attracting more top-level decision-makers
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《China Textile》 2026年第1期46-48,共3页
During 13 to 16 January 2026,with 148 participating nations,rising global relevance and a marked increase in visitor quality,Heimtextil 2026 stood for stability and reliability in a volatile market environment.Once ag... During 13 to 16 January 2026,with 148 participating nations,rising global relevance and a marked increase in visitor quality,Heimtextil 2026 stood for stability and reliability in a volatile market environment.Once again,3,000 exhibitors from across the globe placed their trust in the industry’s central platform in Frankfurt,presenting current collections,materials and textile solutions for holistic interior design to approximately 47,000 buyers.Under the motto“Lead the Change”,Heimtextil brought evolving market dynamics,Artificial Intelligence(AI)and new business opportunities to life.The focus was on progressive design approaches,visionary talents,functional textiles and new hospitality concepts shaping the future of interior design.A tangible sense of confidence and a clear commitment to Heimtextil as a strong industry partner resonated throughout the exhibition halls. 展开更多
关键词 holistic interior design rising global relevance participating nations volatile market environment top level decision makers visitor quality reliability global market relevance
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Simulating Groundwater Levels Responses to Precipitation and Withdrawal:A Lag-time Deep Learning Model
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作者 LI Shuai ZHU Lin +3 位作者 GAO Lei GONG Huili LI Xiaojuan SU Xiaosi 《Chinese Geographical Science》 2026年第2期351-364,共14页
Groundwater level(GWL)is a key indicator used to accurately assess groundwater resources and form the foundation for ef-fective groundwater management.This paper integrates a Gate Recurrent Unit(GRU)model with a Multi... Groundwater level(GWL)is a key indicator used to accurately assess groundwater resources and form the foundation for ef-fective groundwater management.This paper integrates a Gate Recurrent Unit(GRU)model with a Multi-head Self-attention mechan-ism(MSAM-GRU)to simulate GWLs in both confined and unconfined aquifers simultaneously.The model innovatively captures the lag times between GWLs in the unconfined aquifer and precipitation,as well as between GWLs in the confined aquifer and the upper aquifer.We have assessed the effectiveness of the proposed model using a case study in the Beijing Plain,China from January 2005 to December 2020.With the consideration of lag times,the results indicated that the MSAM-GRU model exhibits a maximum 67%and 73%reduction in RMSE compared to the Attention mechanism-GRU(AM-GRU)and GRU model,respectively.MSAM-GRU model exhibited a 31%reduction in RMSE and a 0.12 increase in R^(2) compared to the same model that do not account for lag time.In Region I,the shortest lag time of GWL in the unconfined aquifer was two months,while that in the confined aquifer was three months,indicating a longer delayed response in the confined aquifer.MSAM-GRU model considering lag time,was then applied to simulate the GWLs in the unconfined aquifer under different scenarios and to analyze whether GWL fluctuations affect subway operations.The simulation res-ults showed that under the scenario 1,the GWL in the unconfined aquifer would rise above the depth of subway station floor,threaten-ing the operation of subways.This study can provide reliable technical support for the accurate simulation of GWLs in multi-aquifer systems. 展开更多
关键词 groundwater level(GWL) Multi-head Self-attentionmechanism-Gate Recurrent Unit(MSAM-GRU) PRECIPITATION unconfined aquifer and confined aquifer Beijing Plain China
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Clinical Efficacy of Periosteum-Preserving Iliac Crest Transverse Transport for Symptomatic High-Level Lower Extremity Arteriosclerosis Obliterans
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作者 Guangchen Nie Xiangyue Meng +7 位作者 Yong Liu Xuguang Hao Yang Liu Shouyang Xiang Yongxin Huo Long Jiang Qiang Xu Yicun Lu 《Chronic Diseases and Translational Medicine》 2026年第1期69-72,共4页
Summary What''s New?:This study introduces a novel,periosteum-preserving iliac crest transverse transport(ICTT)technique for high-level lower extremity arteriosclerosis obliterans(LEASO),targeting patients uns... Summary What''s New?:This study introduces a novel,periosteum-preserving iliac crest transverse transport(ICTT)technique for high-level lower extremity arteriosclerosis obliterans(LEASO),targeting patients unsuitable for conventional revascularization.Technical Innovation:By relocating the osteotomy from the weight-bearing tibia to the non-weight-bearing ilium,this minimally invasive technique eliminates the risk of stress fractures,allows for immediate full weight-bearing,and expands indications to patients with proximal arterial occlusions. 展开更多
关键词 iliac crest conventional revascularizationtechnical transverse transport high level lower extremity arteriosclerosis obliterans minimally invasive technique periosteum preserving stress fractures immediate full weight bearing
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The world's first continuous small-radius spiral ramp excavated by tunnel boring machine at China's Beishan Underground Laboratory for high-level radioactive waste disposal
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作者 Ju Wang Jianguo Wang +1 位作者 Xingguang Zhao Jihong Wang 《Deep Underground Science and Engineering》 2026年第1期1-3,共3页
China has achieved a major engineering milestone in the construction of the Beishan Underground Research Laboratory(URL)for geological disposal of high-level radioactive waste(HLW).On December 26,2025,the project team... China has achieved a major engineering milestone in the construction of the Beishan Underground Research Laboratory(URL)for geological disposal of high-level radioactive waste(HLW).On December 26,2025,the project team successfully completed the excavation of the world's first deep,continuous small-radius,steep spiral ramp by a tunnel boring machine(TBM)named Beishan No.1,which marked the completion of the underground main structure of Beishan URL. 展开更多
关键词 underground main structure continuous small radius spiral ramp Beishan Underground Laboratory tunnel boring machine tunnel boring machine tbm named high level radioactive waste disposal engineering milestone
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英国T-Level行动计划的特色、举措与启示
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作者 杨立力 李建国 《荆楚理工学院学报》 2026年第1期16-23,共8页
英国政府为解决高校培养技能与雇主所需技能不匹配问题,推行了T-Level行动计划。T-Level行动计划依据国家与地方两个层面的数据调查,基于雇主和利益相关者需求,制定技能人才的培养目标、课程规划及技术资格认证,强调通过“工作本位”学... 英国政府为解决高校培养技能与雇主所需技能不匹配问题,推行了T-Level行动计划。T-Level行动计划依据国家与地方两个层面的数据调查,基于雇主和利益相关者需求,制定技能人才的培养目标、课程规划及技术资格认证,强调通过“工作本位”学习培养技能,并通过核心知识测评与职业专项技能考核相结合进行技能评价,在一定程度上提升了社会所需技能人才培养的质量。这为我国职业教育中高质量复合型技能人才的培养带来了三点启示:一是构建利益相关者共建、职普融通的技能培养体系;二是创建围绕“工作本位”的技能培养教学和评价模式;三是建立基于人的全面发展需求的多维技能结构。 展开更多
关键词 T-level行动计划 技术教育改革 工作本位学习 雇主项目考核
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Coseismic vertical deformation of the M_S8.0 Wenchuan earthquake from repeated levelings and its constraint on listric fault geometry 被引量:25
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作者 Qingliang Wang Duxin Cui +4 位作者 Xi Zhang Wenping Wang Jinwen Liu Kang Tian Zhaoshan Song 《Earthquake Science》 CSCD 2009年第6期595-602,共8页
The devastating Ms8.0 Wenchuan earthquake ruptured two large parallel thrust faults along the middle segment of the Longmenshan thrust belt. Preseismic and postseismic leveling data indicated the hanging wall of the Y... The devastating Ms8.0 Wenchuan earthquake ruptured two large parallel thrust faults along the middle segment of the Longmenshan thrust belt. Preseismic and postseismic leveling data indicated the hanging wall of the Yingxiu-Beichuan-Nanba thrust fault mainly presented coseismic uplift with respect to the reference point at Pingwu county town, and the observed maximum uplift of 4.7 m is located at Beichuan county (Qushan town) which is about 100 m west of the fault scarp. The foot wall of the Yingxiu-Beichuan-Nanba thrust fault mainly showed subsidence with maximum subsidence of 0.6 m near the rupture. By employing a listric dislocation model, we found that the fault geometry model of exponential dip angle δ=88°×[1-exp(-9/h)] with depth of 18 km and uniform thrust-slip of 5.6 m could fit the observed coseismic vertical deformation very well, which verifies the listric thrust model of the Longmenshan orogenic zone. 展开更多
关键词 Wenchuan earthquake leveling vertical deformation listric faulting
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结合GPS/Leveling和正高改正确定GPS常年观测站正高 被引量:1
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作者 尹弘植 黄鹤 李东河 《测绘通报》 CSCD 北大核心 2008年第3期25-27,共3页
利用精密几何水准测量结合GPS/Leveling方法计算韩国行政自治部管辖内30所GPS常年观测站天线基准点的正高。并联合进行对水准点和GPS常年观测站偏心点的重力测量,使用正高改正方法计算出其改正量,提高正高的精确度。
关键词 GPS常年观测站 几何水准测量 GPS/leveling 重力测量 正高改正 正高
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Numerical Simulation of Continuous Tension Leveling Process of Thin Strip Steel and Its Application 被引量:12
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作者 LI Sheng-zhi YIN Yuan-de +2 位作者 XU Jie HOU Jun-ming Jaehong YOON 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2007年第6期8-13,共6页
Cold-rolled thin strip steel of high flatness quality undergoes multistage deformation during tension leveling. Thus, the parameters of set-up and manipulating are more difficult. With the aid of FE code MSC. MARC, th... Cold-rolled thin strip steel of high flatness quality undergoes multistage deformation during tension leveling. Thus, the parameters of set-up and manipulating are more difficult. With the aid of FE code MSC. MARC, the tension leveling process of thin strip steel was numerically simulated. Concentrating on the influence of the roll intermeshes in 2# anti-cambering on the distribution and magnitude of residual stresses in leveled strip steel, several experiments were clone with the tension leveler based on the results from the simulation. It was found from the simulation that the magnitude of longitudinal residual stresses in the cross-section of the leveled strip steel regularly presents obvious interdependence with the roll intermeshes in 2# anti-cambering. In addition, there is a steady zone as the longitudinal residual stresses of the surface layers in leveled strip steel vary with the roll intermeshes of 2# anticambering, which is of importance in the manipulation of tension levelers. It was also found that the distribution of strains and stresses across the width of strip steel is uneven during leveling or after removing the tension loaded upon the strip, from which it was found that 3D simulation could not be replaced by 2D analysis because 2D analysis in this case cannot represent the physical behavior of strip steel deformation during tension leveling. 展开更多
关键词 cold-rolled strip steel FLATNESS tension leveling numerical simulation shell element residual stress
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Model for the Whole Roller Leveling Process of Plates with Random Curvature Distribution Based on the Curvature Integration Method 被引量:5
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作者 Ben Guan Chao Zhang +1 位作者 Yong Zang Yuan Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期145-155,共11页
A model based on the curvature integration method has been applied in an online plate leveling system. However, there are some shortcomings in the current leveling models. On the one hand, the models cannot deal with ... A model based on the curvature integration method has been applied in an online plate leveling system. However, there are some shortcomings in the current leveling models. On the one hand, the models cannot deal with the leveling process of plates with a random curvature distribution. On the other hand, the current models are suitable only for stable leveling processes and ignore the biting in and tailing out stages. This study presents a new plate-leveling model based on the curvature integration method, which can describe the leveling process of plates with random curvature distribution. Further, the model is solved in two cases in order to take the biting in and tailing out stages into consideration. The proposed model is evaluated by comparing with a plate leveling experiment. Finally, the leveling process of a plate with a wave bent is studied using the proposed model. It is found that the contact angles vary greatly during the biting in and tailing out stages. However, they are relatively steady during the 5 roller leveling stage. In addition, the contact angle of roller No. 2 is the smallest, which is close to 0. Roller leveling can effectively eliminate bending in the plate, but there are regions in the head and tail of the plate, where roller leveling is not effective. The non-leveling region length is about 2 times that of the roller space. This study proposes a quasi-static plate-leveling model, which makes it possible to analyze the dynamic straightening process using a curvature integration method. It also makes it possible to analyze the straightening process of a plate with random curvature distribution. 展开更多
关键词 leveling CURVATURE integration method CURVATURE Contact ANGLE DEFLECTION
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Residual Curvature of Longitudinal Profile Plate Roller in Leveling Process 被引量:6
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作者 CUI Li SHI Quan-qiang +1 位作者 LIU Xiang-hua HU Xian-lei 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2013年第10期23-27,共5页
Roller leveling process of longitudinal profile (LP) plate is hardly studied because plate thickness changes. Deformation characteristics and residual curvature during LP plate leveling process were investigated bas... Roller leveling process of longitudinal profile (LP) plate is hardly studied because plate thickness changes. Deformation characteristics and residual curvature during LP plate leveling process were investigated based on curva ture integral by elastic plastic differences. It was found that entry intermesh section is reduced with increasing thick- ness and entry intermesh should be from 0.7 to 1.1 mm for LP plate with 42/54 mm in thickness. In order to get satisfactory flatness along longitudinal direction, small entry intermesh should be selected and exit intermesh should be 0 ram. In addition, thickness section for I.P plate which can be leveled by 11 roller leveler is from 24 to 60 mm. Finally, there is an intermesh schedule that could level LP plate with initial curvature less than elastic limit curvature. 展开更多
关键词 roller leveling LP plate intermesh residual curvature residual stress
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