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Water level updating model for flow calculation of river networks
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作者 Xiao-ling WU Xiao-hua XIANG +1 位作者 Li LI Chuan-hai WANG 《Water Science and Engineering》 EI CAS CSCD 2014年第1期60-69,共10页
Complex water movement and insufficient observation stations are the unfavorable factors in improving the accuracy of flow calculation of river networks. A water level updating model for river networks was set up base... Complex water movement and insufficient observation stations are the unfavorable factors in improving the accuracy of flow calculation of river networks. A water level updating model for river networks was set up based on a three-step method at key nodes, and model correction values were collected from gauge stations. To improve the accuracy of water level and discharge forecasts for the entire network, the discrete coefficients of the Saint-Venant equations for river sections were regarded as the media carrying the correction values from observation locations to other cross-sections of the river network system. To examine the applicability, the updating model was applied to flow calculation of an ideal river network and the Chengtong section of the Yangtze River. Comparison of the forecast results with the observed data demonstrates that this updating model can improve the forecast accuracy in both ideal and real river networks. 展开更多
关键词 plain river network cyclic looped channel network water level updating model hydrodynamic model error correction
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挑战蓝天的Level Up派诺特Bebop2娱乐型四轴飞行器
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《新潮电子》 2016年第9期98-100,共3页
对派诺特而言,似乎提升Bebop2续航能力最简单的方法便是给它一块大电池,现实中设计师也的确是这么做的——官方标配电池由Bebop1的11.1V1200mAh提升至Bebop2的11.1V2700mAh锂电池。
关键词 level 飞行器 娱乐型 四轴 锂电池 续航能力 设计师
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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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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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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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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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Relationships between income levels,lifestyles,occupational factors,and male fertility in peninsular Malaysia
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作者 Nur Fatma Hasni Majid Suriyani Muhamad +3 位作者 Suhal Kusairi Mohd Nasir Nawawi Noor Salihah Zakaria Roszaman Ramli 《Asian pacific Journal of Reproduction》 2025年第2期69-76,共8页
Objective:To explore the associations between income levels,employment risk,lifestyles,occupational stress,and male fertility.Methods:This cross-sectional study analyzed 294 men seeking fertility treatment at fertilit... Objective:To explore the associations between income levels,employment risk,lifestyles,occupational stress,and male fertility.Methods:This cross-sectional study analyzed 294 men seeking fertility treatment at fertility clinics in Terengganu,Pahang,and Kuala Lumpur from November 2021 to June 2023.Data were collected through structured questionnaires covering income levels,lifestyles,employment risks,occupational stress,and semen quality.Multinomial logistic regression was employed to assess predictors of semen quality,with crude and adjusted odds ratios(OR)reported.Results:The lower-income group exhibited higher odds of having abnormal semen quality compared to normal semen quality.Specifically,these participants were more likely to experience azoospermia[crude OR 6.68,95%confidence interval(CI)1.84-52.63;adjusted OR 6.26,95%CI 1.76-51.38],indicating a link between low income and infertility issues.Lifestyle factors did not show significant associations with semen abnormalities after adjustment.High employment risks had significant associations with oligozoospermia after adjustment(crude OR 5.50,95%CI 2.14-14.11;adjusted OR 5.15,95%CI 1.93-13.71),while high occupational stress was linked to asthenozoospermia(crude OR 2.26,95%CI 1.09-4.68;adjusted OR 2.25,95%CI 1.07-4.69).Conclusions:The findings underscore the influence of socioeconomic and occupational factors on male fertility,showing associations between lower income levels,high-risk occupations,and semen abnormalities.In contrast,lifestyle factors did not show significant associations with semen abnormalities after adjustment.Nevertheless,the current findings should be further confirmed through more extensive studies focusing on abnormal semen and lifestyle factors. 展开更多
关键词 Male infertility Income levels Employment risks Occupational stress Lifestyles
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Abnormal salinity levels increase shrimp Penaeus monodon disease risk:insights from the disrupted gut microbiota
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作者 Yufeng WANG Yangming LU +1 位作者 Qiongfen QIU Jinbo XIONG 《Journal of Oceanology and Limnology》 2025年第6期2002-2018,共17页
Owing to the extreme rainfall and evaporation events under the changing climate,coastal zones are experiencing salinity fluctuations that stress aquatic organisms.However,the biological consequences of ongoing alterat... Owing to the extreme rainfall and evaporation events under the changing climate,coastal zones are experiencing salinity fluctuations that stress aquatic organisms.However,the biological consequences of ongoing alteration in salinity levels on euryhaline organisms remain inconclusive.Herein,we sought to uncover how variation in salinity level adversely alters the bacterioplankton community,the gut microbiota of euryhaline shrimp Penaeus monodon,and subsequent shrimp disease risk.To mimic the extreme weather that induces abrupt changes in coastal water salinity,three salinity levels(10,20,and 30)were selected to investigate the differences in shrimp gut microbiota using bacterial 16S rRNA gene sequencing.Results shows that salinity level and days post experiment(dpe)respectively constrained 45.9%and 13.0%of the variance in the gut bacterial communities.Particularly,abnormal salinity levels accelerated temporal turnover rate,disrupted gut network stability,augmented average variation degree,and increased pathogenic potential in the gut microbiota of shrimp reared at 10 and 30 salinities compared with 20 salinity controls.These changes were accompanied with the shifts in the gut microbiota-mediated functions,especially the compromised immunity and elevated infectious diseases potentials,thereby increasing shrimp disease risk.In addition,abnormal salinity levels increased the role of homogeneous selection governing the gut microbiota.After excluding the dpe-effect,we screened 35 gut salinity-discriminatory taxa that quantitatively discriminated the salinity levels where shrimp were reared,with overall accuracy of 91.1%.Collectively,abnormal salinity levels profoundly disrupt the structure,stability,assembly,and functions of the gut microbiota,which in turn increased disease risk in shrimp.In addition,gut symbionts sensitively responded to the changes in external salinity level.These findings deepened our understanding on the biological consequence of abnormal salinity levels on shrimp health. 展开更多
关键词 Penaeus monodon abnormal salinity level gut microbiota ecological process disease risk
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Level-Set-Based Topology Optimization of a Geometrically Nonlinear Structure Considering Thermo-mechanical Coupling Effect
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作者 Sujun Wang An Xu Ruohong Zhao 《Acta Mechanica Solida Sinica》 2025年第1期100-114,共15页
This paper presents an improved level set method for topology optimization of geometrically nonlinear structures accounting for the effect of thermo-mechanical couplings.It derives a new expression for element couplin... This paper presents an improved level set method for topology optimization of geometrically nonlinear structures accounting for the effect of thermo-mechanical couplings.It derives a new expression for element coupling stress resulting from the combination of mechanical and thermal loading,using geometric nonlinear finite element analysis.A topological model is then developed to minimize compliance while meeting displacement and frequency constraints to fulfill design requirements of structural members.Since the conventional Lagrange multiplier search method is unable to handle convergence instability arising from large deformation,a novel Lagrange multiplier search method is proposed.Additionally,the proposed method can be extended to multi-constrained geometrically nonlinear topology optimization,accommodating multiple physical field couplings. 展开更多
关键词 Topology optimization Geometric nonlinearity Thermo-mechanical coupling effect level set method Multiple constraints
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Assessing the impact of upstream water quality levels on downstream economic growth in China:A high-resolution panel study
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作者 DING Yu WANG Chenglong +3 位作者 SHUAI Chenyang CHEN Xi SUN Jingran ZHAO Bu 《Journal of Geographical Sciences》 2025年第12期2647-2663,共17页
In light of growing challenges posed by water pollution,understanding the multifaceted impacts of water quality on economic performance is an imperative for formulating effective policies aimed at sustainable developm... In light of growing challenges posed by water pollution,understanding the multifaceted impacts of water quality on economic performance is an imperative for formulating effective policies aimed at sustainable development.Existing studies tend to be constrained by limited local data,and lack a perspective on spatial dynamics and regional variations in water quality effects.This study addresses these gaps by examining the influence of upstream water quality on downstream economic growth in China,utilizing high-resolution panel data.Findings reveal that a 1%increase in upstream biochemical oxygen demand(BOD)concentration reduces downstream economic growth by 0.25% nationally.Regionally,the constraining effect varies significantly,ranging from 0.38% in Southwest China(β=-0.38)to 0.92% in North China(β=-0.92).Notably,even in regions with non-polluted water,upstream water quality deterioration continues to impede downstream economic growth.These findings underscore the critical need to integrate water quality considerations into economic policy frameworks and highlight the importance of coordinated,cross-regional water quality management strategies to foster sustainable economic development. 展开更多
关键词 water quality economic growth spatial dynamics water quality levels
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Electronic modulation of MOF-engineered bimetallic phosphides for cost-effective ampere-level water splitting and continuous hydrogen production via supercapacitor integration
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作者 Mohd Afshan Naveen Kumar +9 位作者 Subhabrata Das Harini E.M Daya Rani Soumyadip Sharangi Mansi Pahuja Shumile Ahmed Siddiqui Seema Rani Nikita Chaudhary Chandan Bera Kaushik Ghosh 《Journal of Energy Chemistry》 2025年第9期221-238,I0008,共19页
Engineering a phosphide-based multifunctional heterostructure with high redox activity,stability,and efficient charge kinetics for both supercapacitors and water splitting remains challenging due to sluggish reaction ... Engineering a phosphide-based multifunctional heterostructure with high redox activity,stability,and efficient charge kinetics for both supercapacitors and water splitting remains challenging due to sluggish reaction kinetics and structural instability.This study overcomes these challenges by implementing a rapid,energy-efficient approach to develop a MOF-modulated MnP@Cu_(3)P heterostructure via a hydrothermal process followed by high-temperature phosphorization.The heterostructure demonstrates superior redox activity with enhanced stability and improved charge kinetics achieving a high specific capacity of 1131 C g^(-1)as supported by density functional theory findings of increased DOS near the Fermi level.The flexible supercapacitor achieves a peak energy density of 99.20 Wh kg^(-1)and power density of 15.40 kW kg^(-1).Simultaneously,it shows exceptional hydrogen evolution reaction performance with an overpotential of η_(10)=44 mV and η_(1000)=225 mV,attributed to electron transfer from Cu to Mn via P bridging,which shifts the active centers from Mn and Cu sites to the P site,confirmed by lowestΔG_(H)^(*)value of-0.16 eV.The overall water-splitting in full-cell electrocatalyzer delivers cell voltage of E_(20)=1.48 V and E_(1000)=1.88 V and setting a new standard in solar-to-hydrogen efficiency of 20.02%.The electrolyzer cell maintained prolonged stability at industrial-scale current densities of 1.0 A cm^(-2)under alkaline electrolysis achieving an estimated hydrogen production cost of INR 146.7 or US$1.67per kilogram aligning with the cost target of $2/kg by 2026 established by the Clean Hydrogen Electrolysis Program,U.S.department of energy.Furthermore,real-phase demonstration highlights the uninterrupted hydrogen production till 6-minutes via connecting this electrocatalyzer with photovoltaic-charged supercapacitors effectively addressing solar intermittency and gas fluctuations challenges in water-electrolysis. 展开更多
关键词 Bimetallic phosphides Interface engineering Hybrid supercapacitors Solar-to-hydrogen conversion Ampere level current density
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Analysis of Community Elderly Care Facility Demand Levels and Functional Grouping Insights: A Case Study of Xueyuan Road Street in Haidian District, Beijing
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作者 GUO Yuhan CAO Ying 《Journal of Landscape Research》 2025年第3期27-32,共6页
This study focuses on the elderly population in Xueyuan Road Street of Haidian District in Beijing.Through KANO questionnaires and the theory of attractive quality,it investigates the demand levels and degrees for dif... This study focuses on the elderly population in Xueyuan Road Street of Haidian District in Beijing.Through KANO questionnaires and the theory of attractive quality,it investigates the demand levels and degrees for different community elderly care services.It introduces the Anderson behavioral model to analyze the influencing factors,categorizes different demographics,and examines the needs of elderly individuals with varying characteristics,proposing suggestions for the improvement of future community elderly care service facilities. 展开更多
关键词 Community elderly care Demand levels KANO model Anderson behavioral model
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A Total Variational Image Denoising Model Coupled with a New Non-local Edge Extractor and a Level Set Curvature Gradient
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作者 Zhou Han Xianchun Zhou +1 位作者 Binxin Tang Siqi Lu 《Instrumentation》 2025年第2期47-59,共13页
To solve the problem of false edges in a flat region of l_(1)norm total variational TV model,an edge extractor based on non-local idea is proposed in this paper.The new edge extractor can effectively suppress the infl... To solve the problem of false edges in a flat region of l_(1)norm total variational TV model,an edge extractor based on non-local idea is proposed in this paper.The new edge extractor can effectively suppress the influence of noise and extract the edge information of the image.The new edge extractor is used as the adaptive function and the weighting function of the l_(p) norm variational model to control the noise reduction ability of the model,and a new model 1 is obtained.Considering that the new model 1 only uses the gradient mode as the image feature operator,which is insufficient to express the image texture information,a new level set curvature gradient variational model 2 combined with the edge extractor is proposed.The new model 2 uses the idea of minimum curvature of the level set of clear images to obtain noise reduction images.By coupling new model 1 and new model 2 to smooth the noise and protect more textures,a new Non-local level set denoising model(NLSDM)for image noise reduction is obtained.The experimental results show that compared with the noise reduction model,the new model has significantly improved the peak signal-to-noise ratio and structural similarity,and the effect of noise reduction and edge preservation is better. 展开更多
关键词 TV model the l_(p)norm NONLOCAL pfunction level set curvature term of regularization
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Application of K-Type Heated Junction Thermocouples for Water Level Measurement in PWR and BWR Reactors:A Comparative Study of 2-Wire vs.3-Wire Connections
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作者 Bahman Zohuri 《Journal of Energy and Power Engineering》 2025年第4期127-132,共6页
Accurate water level measurement in nuclear reactors,particularly in PWRs(pressurized water reactors)and BWRs(boiling water reactors),is essential for ensuring the safety and efficiency of reactor operations.K-type HJ... Accurate water level measurement in nuclear reactors,particularly in PWRs(pressurized water reactors)and BWRs(boiling water reactors),is essential for ensuring the safety and efficiency of reactor operations.K-type HJTCs(heated junction thermocouples)are widely used for this purpose due to their ability to withstand extreme temperatures and radiation conditions.This article explores the role of HJTCs in reactor water level measurement and compares the performance of 2-wire and 3-wire connections.While the 2-wire connection is simple and cost-effective,it can introduce measurement inaccuracies due to wire resistance.In contrast,the 3-wire connection compensates for lead resistance,offering more precise and reliable measurements,particularly in long-distance applications.This paper discusses the operational considerations of these wiring configurations in the context of nuclear reactors and highlights the importance of choosing the appropriate connection type to optimize safety and measurement accuracy in PWR and BWR reactors. 展开更多
关键词 K-type thermocouple heated junction water level measurement PWR BWR temperature measurement nuclear reactor instrumentation thermocouple wiring configurations 2-wire vs.3-wire connection radiation resistance
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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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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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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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The need to consider regional supply chains and water usage in H_(2)–steel transition
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作者 Peng Peng Tae Lim +3 位作者 Fabian Rosner Hanna Breunig Prakash Rao Arman Shehabi 《Green Energy & Environment》 2026年第1期23-35,共13页
The iron and steel industry is one of the largest contributors to U.S.and global greenhouse gas emissions.Hydrogen can act as a promising reducing agent and clean energy carrier to decarbonize this sector,and has rece... The iron and steel industry is one of the largest contributors to U.S.and global greenhouse gas emissions.Hydrogen can act as a promising reducing agent and clean energy carrier to decarbonize this sector,and has received significant attention in terms of process modelling,techno-economic analysis,and life cycle assessment in recent years.Policy incentives,hydrogen storage and transportation,and water stress levels are key factors that require significantly more consideration in order to realize hydrogen's potential to decarbonize this industry.This review demonstrates the need for a systematic understanding and critical assessment of these areas,and their profound impacts on the decarbonization of the iron and steel sector.Furthermore,hydrogen and water supply face competition from other hard-to-decarbonize sectors,which should be considered on national and regional levels.Lastly,future research should also consider the impact of other environmental factors and hydrogen leak when deploying hydrogen at scale for industrial decarbonization. 展开更多
关键词 Iron and steel Green steel Hydrogen Industrial decarbonization Water stress level
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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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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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