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数据中心冷却与余热回收协同性能优化及不确定性分析
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作者 陈姝伊 张泉 +3 位作者 朱轶群 翟志强 李俊山 郭振君 《制冷学报》 北大核心 2026年第1期59-70,共12页
数据中心冷却与余热回收系统多参数耦合导致控制复杂,模型、测量及执行误差显著降低控制精度,制约系统能效提升。本文针对多目标冲突影响数据中心综合性能,以及参数不确定性导致的性能波动、运行风险量化难题,以东江湖大数据产业园湖水... 数据中心冷却与余热回收系统多参数耦合导致控制复杂,模型、测量及执行误差显著降低控制精度,制约系统能效提升。本文针对多目标冲突影响数据中心综合性能,以及参数不确定性导致的性能波动、运行风险量化难题,以东江湖大数据产业园湖水源冷却-余热回收耦合系统为对象,提出兼顾系统能耗与运行费用的多目标优化策略,并采用蒙特卡洛模拟量化控制策略在不确定性下的鲁棒性。相较于规则控制,多目标优化使耦合系统能耗与运行费用分别降低11.07%和16.25%,PUE降低0.01;对比单目标能耗优化,其能耗仅增加0.28%而运行费用降低3.20%;与单目标电费优化相比,能耗降低0.77%且运行费用仅增加0.54%。多目标优化通过多目标协同,虽单一性能指标变异系数略高于单目标优化,其能耗变异系数比单目标电费优化低2.8%,电费变异系数比单目标能耗优化低2.2%,蓄放热模式误判率相对较低,在多参数不确定性下具有全局鲁棒性优势。 展开更多
关键词 数据中心 余热回收 多目标优化 不确定参数 控制策略
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New insights into the phylogeny of Stephanodiscaceae based on plastome
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作者 Yandan XIANG Xudong LIU +5 位作者 Fangru NAN Yang LIU Shulian XIE Xinjie JIN John Patrick KOCIOLEK Qi LIU 《Journal of Oceanology and Limnology》 2026年第1期284-306,共23页
Stephanodiscaceae is one of the most diverse family of the freshwater centric diatoms.However,the scarcity of whole plastome data poses a significant challenge to the undertaking of genomic studies on this taxonomic g... Stephanodiscaceae is one of the most diverse family of the freshwater centric diatoms.However,the scarcity of whole plastome data poses a significant challenge to the undertaking of genomic studies on this taxonomic group.We collected data on the plastid genomes from 33 members of the Stephanodiscaceae and its close relatives,including 12 newly-sequenced genomes and 21 deposited in National Center for Biotechnology Information(NCBI).Phylogenetic trees are yielded five major clades based on homologous genes.The features of the plastid genomes,including repeat sequences,codon usage,and selection pressure for each clade,are analyzed.The paper makes a contribution to the field of diatom genomics by describing the structural characteristics of the plastid genomes in the Stephanodiscaceae and its closely related species,complemented by related analyses.It provides crucial data that will serve as indispensable references for future research. 展开更多
关键词 chloroplast genome PHYLOGENOMICS plastome evolution Stephanodiscaceae
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从设计到制造,全部出自自家工厂专访Boulder总裁Jeff Nelson
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作者 Jeff Nelson 《家庭影院技术》 2018年第9期108-108,共1页
自1984年创立BOUIderAmPMiers以来,我就极为注重制造工艺。Boulder的产品,我可以告诉你,从设计到制造,几乎不假他人之手。为此BouIder有自己的贴片工厂、金属加工厂还有专门的组装车间。像是标志性的功放散热器,就由耗费巨资添置的... 自1984年创立BOUIderAmPMiers以来,我就极为注重制造工艺。Boulder的产品,我可以告诉你,从设计到制造,几乎不假他人之手。为此BouIder有自己的贴片工厂、金属加工厂还有专门的组装车间。像是标志性的功放散热器,就由耗费巨资添置的OCNC机床来完成铝块的切削、打磨、喷砂等全部工序。这在放大器厂商中称不上绝无仅有,不过应该也是非常罕见的,我对品质的坚持,令BouIder今天愿意为此而倾情付出。 展开更多
关键词 金属加工厂 制造工艺 设计 总裁 CNC机床 散热器 标志性 放大器
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大数据园区综合能源系统控制策略优化研究
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作者 张泉 李俊 +4 位作者 翟志强 朱轶群 陈姝伊 雷建军 廖曙光 《湖南大学学报(自然科学版)》 北大核心 2025年第11期178-189,共12页
为了实现大数据园区低碳、高效运行,构建了耦合光伏发电系统、自然冷却系统、余热回收系统和多种储能方式的综合能源系统.建立了综合能源系统能耗模型,针对模型非线性、多变量、多约束条件的特性,提出了基于遗传算法的滚动优化控制方法... 为了实现大数据园区低碳、高效运行,构建了耦合光伏发电系统、自然冷却系统、余热回收系统和多种储能方式的综合能源系统.建立了综合能源系统能耗模型,针对模型非线性、多变量、多约束条件的特性,提出了基于遗传算法的滚动优化控制方法,以应对能源供需动态变化的问题.该方法以系统运行成本最低为目标,综合考虑峰谷电价、可再生能源出力特性、设备部分负载性能特性等因素,确定系统的最佳运行策略.将模拟结果与规则控制的结果对比可知,滚动优化可使系统运行费用降低10.68%~12.63%.此外,选择了不同太阳辐射强度的场景进行研究,结果表明:光伏利用率的提升受蓄电池运行模式影响较大,通过调整系统运行参数能进一步提高系统光伏利用率. 展开更多
关键词 综合能源系统 数据中心 优化调度 储能
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数据中心园区的负载迁移和多能源调控策略优化
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作者 丁中亮 张泉 +4 位作者 李俊山 雷建军 廖曙光 翟志强 马贞俊 《科学技术与工程》 北大核心 2025年第33期14267-14276,共10页
为实现数据中心园区的低成本运营,构建了面向全湖水自然冷却数据中心的多能源系统。针对可再生能源发电的波动性及峰谷电价差异,提出了一种基于特定时空规则控制的粒子群算法优化的负载迁移与蓄/放电精细化调控策略,将延迟容忍算力负载... 为实现数据中心园区的低成本运营,构建了面向全湖水自然冷却数据中心的多能源系统。针对可再生能源发电的波动性及峰谷电价差异,提出了一种基于特定时空规则控制的粒子群算法优化的负载迁移与蓄/放电精细化调控策略,将延迟容忍算力负载与可再生能源出力、电价时段精准匹配,减少了配置容量冗余与绿电损耗,储能设备容量配置降低了23.1%;全年运行电费节省了19.7%,夏季和过渡季的绿电损耗率分别降低1.5%、0.4%;电源使用效率(power usage effectiveness,PUE)从1.121降至1.115,该策略为多能源与负载调度的优化提供了参考。 展开更多
关键词 数据中心园区 负载迁移 设备容量优化 能源管理 制冷系统 粒子群优化算法
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太平洋和北大西洋海表面温度年代际变率对1979~2014年南极海冰趋势季节性及区域性贡献的比较
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作者 杨璐萍 吴其冈 +1 位作者 户元涛 Aixue HU 《大气科学》 北大核心 2025年第3期814-834,共21页
基于美国国家冰雪数据中心最新发布的卫星观测海冰资料,本文分析了1979~2014年南极海冰空间趋势的季节变化特征,并比较了太平洋年代际振荡(IPO)和大西洋多年代际振荡(AMO)位相转换对南极海冰趋势的相对贡献与影响机制。结果表明:1979~2... 基于美国国家冰雪数据中心最新发布的卫星观测海冰资料,本文分析了1979~2014年南极海冰空间趋势的季节变化特征,并比较了太平洋年代际振荡(IPO)和大西洋多年代际振荡(AMO)位相转换对南极海冰趋势的相对贡献与影响机制。结果表明:1979~2014年间,罗斯海和南印度洋四个季节海冰密集度(SIC)均呈现增加趋势,在暖季(12~5月),阿蒙森海和别林斯高晋海的SIC显著减少,威德尔海的SIC显著增加,呈正位相的南极偶极子(ADP),而在冷季(6~11月份),阿蒙森海—别林斯高晋海—威德尔海SIC表现为负位相ADP趋势,南极整体年平均和季节平均海冰范围(SIE)均具有显著增加趋势。1979~2014年IPO从正位相向负位相转换通过激发太平洋—南美(PSA)大气遥相关加深阿蒙森海低压(ASL),为南半球冬季和春季负ADP海冰趋势的主要成因。1979~2014年AMO从负位相向正位相转换在南半球春季通过激发罗斯贝波和跨海盆激发PSA波列,加深ASL,并可能通过减弱埃克曼抽吸抑制绕极近海混合层暖海水上翻,进而导致东罗斯海、阿蒙森海及南印度洋的海冰显著增加,解释约75%的春季南极整体SIE增加趋势。在南半球夏季,IPO和AMO位相转换均可增强南半球环状模(SAM),从而对夏季南极海冰增加和正位相ADP型海冰趋势有一定贡献。以上结果表明1979~2014年IPO和AMO位相转换通过大气遥相关机制对南极海冰趋势产生的影响呈现明显的季节性和区域性差异。 展开更多
关键词 南极海冰 趋势 南极偶极子 太平洋年代际振荡 大西洋多年代际振荡 大气遥相关
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生物性别与SARM1基因敲除对弥漫性创伤性脑损伤后胶质细胞的独立影响
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作者 Yasmine V Doust Rachel K Rowe +3 位作者 Ross C Langley Anna E King Jenna M Ziebell 王晶(编译) 《神经损伤与功能重建》 2025年第11期F0003-F0003,共1页
由小胶质细胞和星形胶质细胞介导的神经炎症是创伤性脑损伤(TBI)病理生理过程的主要组成部分。已发现含无菌α和TIR基序蛋白1(SARM1)在神经退行性变和炎症级联反应中发挥关键作用。因此,我们假设抑制SARM1可预防创伤性脑损伤后胶质细胞... 由小胶质细胞和星形胶质细胞介导的神经炎症是创伤性脑损伤(TBI)病理生理过程的主要组成部分。已发现含无菌α和TIR基序蛋白1(SARM1)在神经退行性变和炎症级联反应中发挥关键作用。因此,我们假设抑制SARM1可预防创伤性脑损伤后胶质细胞的反应性,并可作为治疗干预的靶点。本研究通过中线液体冲击损伤模型,对野生型(WT)和SARM1基因敲除(SARM1-KO)的两种生物性别的小鼠进行创伤性脑损伤模拟。在损伤后7 d或28 d时,收集小鼠大脑,通过免疫组织化学法检测胶质细胞反应性,并与未损伤的对照组进行比较。结果显示,损伤后不同时间点,小胶质细胞密度和星形胶质细胞的胶质纤维酸性蛋白(GFAP)免疫反应性均显著增加。此外,损伤后7 d时,小胶质细胞形态发生改变,且与吞噬作用替代标记物(CD68)的共定位增加。在无SARM1的情况下,无论是否发生创伤性脑损伤,小胶质细胞密度及与CD68的共定位均高于野生型动物。然而,SARM1基因敲除对GFAP免疫反应性并无影响。在研究生物性别差异时发现,损伤后7 d,雄性小鼠创伤性脑损伤引起的小胶质细胞密度和细胞体积增加更为显著;然而,雌性小鼠的小胶质细胞分支更少。雄性和雌性小鼠的GFAP免疫反应性无显著差异。这些结果表明,SARM1基因敲除不足以改变星形胶质细胞的GFAP标记;然而,SARM1似乎会影响未损伤和损伤大脑中的小胶质细胞密度及与CD68的共定位。 展开更多
关键词 SARM1 创伤性脑损伤 星形胶质细胞 生物性别 小胶质细胞 神经退行性变
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Isotopic Analysis for Tracing Vertical Growth Trajectories of Hailstones 被引量:1
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作者 Xiangyu LIN Haifan ZHANG +6 位作者 Xiaofei LI Qinghong ZHANG Andrew HEYMSFIELD Kai BI Chan-Pang NG Chong WU Dianli GONG 《Advances in Atmospheric Sciences》 2025年第6期1195-1211,共17页
The growth trajectory of hailstones within clouds has remained elusive due to the inability to trace them directly,impeding the comprehension of their underlying growth mechanisms.This study investigated hailstone ver... The growth trajectory of hailstones within clouds has remained elusive due to the inability to trace them directly,impeding the comprehension of their underlying growth mechanisms.This study investigated hailstone vertical growth trajectories by detecting the stable isotope signatures(2H and 18O compositions)of different shells in 27 hailstones from 9hailstorms,which allowed us to capture the ambient temperature during hailstone growth.The vertical growth trajectories were obtained by comparing the isotopic compositions of water condensate in clouds,derived from the Adiabatic Model,with those measured in hailstones.Although hailstone growth was primarily observed in the–10°C to–30°C temperature layer,the embryo formation height and subsequent growth trajectories significantly varied among hailstones.Embryos formed over a wide range of temperatures(–8.7°C to–33.4°C);four originated at temperatures above–15°C and 16originated at temperatures below–20°C,suggesting ice nuclei composed of bioproteins and mineral dust,respectively.Among the 27 measured hailstones,3 exhibited minimal vertical movement,16 exhibited a monotonic rise or fall,and the remaining 8 exhibited alternating up-down trajectories;only one experienced“recycling”during up-down drifting.Trajectory analysis revealed that similar-sized hailstones from a single storm tended to form at similar heights,whereas those larger than 25 mm in diameter exhibited at least one period of upward growth.Vertical trajectories derived from isotopic analysis were corroborated by radar hydrometeor observations. 展开更多
关键词 growth trajectory hailstone HAILSTORM isotopic analysis RADAR
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Monetary policy shocks and multi‑scale positive and negative bubbles in an emerging country:the case of India
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作者 Oguzhan Cepni Rangan Gupta +1 位作者 Jacobus Nel Joshua Nielsen 《Financial Innovation》 2025年第1期1109-1133,共25页
We employ the Multi-Scale Log-Periodic Power Law Singularity Confidence Indicator(MS-LPPLS-CI)approach to identify positive and negative bubbles in the short-,medium,and long-term for the Indian stock market,using wee... We employ the Multi-Scale Log-Periodic Power Law Singularity Confidence Indicator(MS-LPPLS-CI)approach to identify positive and negative bubbles in the short-,medium,and long-term for the Indian stock market,using weekly data from November 2003 to December 2020.We use a nonparametric causality-in-quantiles approach to analyze the predictive impact of monetary policy shocks on bubble indicators.We find,in general,strong evidence of predictability across the entire conditional distribution for the two monetary policy shock factors,with stronger impacts for negative bubbles.Our findings have critical implications for the Reserve Bank of India,academics,and investors. 展开更多
关键词 Multi-scale positive and negative bubbles Monetary policy shocks Nonparametric causality-in-quantiles test INDIA
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Intrinsic Functional Connectivity Associated with γ‑Aminobutyric Acid and Glutamate/Glutamine in the Lateral Prefrontal Cortex and Internalizing Psychopathology in Adolescents
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作者 Kai Wang Harry R.Smolker +4 位作者 Mark S.Brown Hannah R.Snyder Yu Cheng Benjamin L.Hankin Marie T.Banich 《Neuroscience Bulletin》 2025年第9期1553-1569,共17页
In this study,we systematically tested the hypothesis that during the critical developmental period of adolescence,on a macro scale,the concentrations of major excitatory and inhibitory neurotransmitters(glutamate/glu... In this study,we systematically tested the hypothesis that during the critical developmental period of adolescence,on a macro scale,the concentrations of major excitatory and inhibitory neurotransmitters(glutamate/glutamine andγ‑aminobutyric acid[GABA])in the dorsal and ventral lateral prefrontal cortex are associated with the brain’s functional connectivity and an individual’s psychopathology.Neurotransmitters were measured via magnetic resonance spectroscopy while functional connectivity was measured with resting-state fMRI(n=121).Seed-based and network-based analyses revealed associations of neurotransmitter concentrations and functional connectivities between regions/networks that are connected to prefrontal cortices via structural connections that are thought to be under dynamic development during adolescence.These regions tend to be boundary areas between functional networks.Furthermore,several connectivities were found to be associated with individual’s levels of internalizing psychopathology.These findings provide insights into specific neurochemical mechanisms underlying the brain’s macroscale functional organization,its development during adolescence,and its potential associations with symptoms associated with internalizing psychopathology. 展开更多
关键词 Functional connectivity GLUTAMATE GABA MR spectroscopy Resting state fMRI PSYCHOPATHOLOGY
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Interfacial engineering and rapid thermal crystallization of Sb_(2)S_(3)photoanodes for enhanced photoelectrochemical performances
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作者 Runfa Tan Seo Yeong Hong +2 位作者 Yoo Jae Jeong Seong Sik Shin In Sun Cho 《Journal of Energy Chemistry》 2025年第9期417-426,I0012,共11页
Antimony sulfide(Sb_(2)S_(3))is a promising material for photoelectrochemical(PEC)devices that generate green hydrogen from sunlight and water.In this study,we present a synthesis of high-performance Sb_(2)S_(3)photoa... Antimony sulfide(Sb_(2)S_(3))is a promising material for photoelectrochemical(PEC)devices that generate green hydrogen from sunlight and water.In this study,we present a synthesis of high-performance Sb_(2)S_(3)photoanodes via an interface-engineered hydrothermal growth followed by rapid thermal annealing(RTA).A TiO_(2)interfacial layer plays a crucial role in ensuring homogeneous precursor deposition,enhancing light absorption,and forming efficient heterojunctions with Sb_(2)S_(3),thereby significantly improving charge separation and transport.RTA further improves crystallinity and interfacial contact,resulting in dense and uniform Sb_(2)S_(3)films with enlarged grains and fewer defects.The optimized Sb_(2)S_(3)photoanode achieves a photocurrent density of 2.51 mA/cm^(2)at 1.23 V vs.the reversible hydrogen electrode(RHE),one of the highest reported for Sb_(2)S_(3)without additional catalysts or passivation layers.To overcome the limitations of oxygen evolution reaction(OER),we employ the iodide oxidation reaction(IOR)as an alternative,significantly lowering the overpotential and improving charge transfer kinetics.Consequently,it produces a record photocurrent density of 8.9 mA/cm^(2)at 0.54 V vs.RHE.This work highlights the synergy between TiO_(2)interfacial engineering,RTA-induced crystallization,and IOR-driven oxidation,offering a promising pathway for efficient and scalable PEC hydrogen production. 展开更多
关键词 Antimony sulfide(Sb_(2)S_(3)) TiO_(2)heterojunction Hydrothermal synthesis Rapid thermal annealing(RTA) Photoelectrochemical hydrogen production Iodide oxidation reaction(IOR)
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A review of photovoltaic/thermal(PV/T)incorporation in the hydrogen production process
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作者 Hussein A.Kazem Miqdam T.Chaichan +4 位作者 Ali H.A.Al-Waeli K.Sopian Waheeb E.Alnaser Lawrence Kazmerski Naser W.Alnaser 《Global Energy Interconnection》 2025年第3期363-393,共31页
Integrating the photovoltaic/thermal(PV/T)system in green hydrogen production is an improvement in sustainable energy technologies.In PV/T systems,solar energy is converted into electricity and thermal energy simultan... Integrating the photovoltaic/thermal(PV/T)system in green hydrogen production is an improvement in sustainable energy technologies.In PV/T systems,solar energy is converted into electricity and thermal energy simultaneously using hot water or air together with electricity.This dual use saves a significant amount of energy and officially fights greenhouse gases.Different cooling techniques have been proposed in the literature for improving the overall performance of the PV/T systems;employing different types of agents including nanofluids and phase change materials.Hydrogen is the lightest and most abundant element in the universe and has later turned into a flexible energy carrier for transportation and other industrial applications.Issues,including the processes of Hydrogen manufacturing,preservation as well as some risks act as barriers.This paper provides an analysis of several recent publications on the efficiency of using PV/T technology in the process of green hydrogen production and indicates the potential for its increased efficiency as compared to conventional systems that rely on fossil fuels.Due to the effective integration of solar energy,the PV/T system can play an important role in the reduction of the levelized cost of hydrogen(LCOH)and hence play an important part in reducing the economic calculations of the decarbonized energy system. 展开更多
关键词 PV/T Green hydrogen PRODUCTION Liquification Technology readiness levels Levelized cost of hydrogen
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Measurements of the Solar Coronal Magnetic Field Based on Coronal Seismology with Propagating Alfvénic Waves:Forward Modeling
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作者 Yuhang Gao Hui Tian +3 位作者 Tom Van Doorsselaere Zihao Yang Mingzhe Guo Konstantinos Karampelas 《Research in Astronomy and Astrophysics》 2025年第1期238-246,共9页
Recent observations have demonstrated the capability of mapping the solar coronal magnetic field using the technique of coronal seismology based on the ubiquitous propagating Alfvénic/kink waves through imaging s... Recent observations have demonstrated the capability of mapping the solar coronal magnetic field using the technique of coronal seismology based on the ubiquitous propagating Alfvénic/kink waves through imaging spectroscopy.We established a magnetohydrodynamic model of a gravitationally stratified open magnetic flux tube,exciting kink waves propagating upwards along the tube.Forward modeling was performed to synthesize the Fe XIII 1074.7 and 1079.8 nm spectral line profiles,which were then used to determine the wave phase speed,plasma density,and magnetic field with seismology method.A comparison between the seismologically inferred results and the corresponding input values verifies the reliability of the seismology method.In addition,we also identified some factors that could lead to errors during magnetic field measurements.Our results may serve as a valuable reference for current and future coronal magnetic field measurements based on observations of propagating kink waves. 展开更多
关键词 SUN corona-Sun magnetic fields-magnetohydrodynamics(MHD)
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Skin tone bias in online psoriasis imagery:Insights from an international study
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作者 Aman Sandhu Sanya Ailani +4 位作者 Smitesh Padte Priyal Mehta Neha Deo Salim Surani Rahul Kashyap 《World Journal of Clinical Cases》 2025年第36期6-12,共7页
BACKGROUND Psoriasis is often first recognized by patients through online image searches.However,search engine algorithms influenced by geographic location may still produce results that predominantly feature lighter ... BACKGROUND Psoriasis is often first recognized by patients through online image searches.However,search engine algorithms influenced by geographic location may still produce results that predominantly feature lighter skin tones,regardless of the region’s majority skin type.This underrepresentation may limit recognition and delay care for people of color.AIM To examine whether search algorithms tailor region-specific results in terms of skin color for psoriasis imagery.METHODS This observational study recruited 66 participants from 18 countries who conducted image searches for“psoriasis”across various web browsers.During the meeting,a Google form was posted to record observations,and participants reported the diversity of skin tones in the first three rows of search results using a reference image depicting Fitzpatrick types.RESULTS Results showed a global bias toward lighter skin tones,with 94%of participants identifying light skin predominance in the first row and minimal representation of medium or darker skin tones in subsequent results,verified via χ^(2) analysis.Participants who observed darker or mixed skin tones typically found them further down their results.CONCLUSION There remains a significant gap in global representation of psoriasis imagery.This paper deepens the current understanding of bias in online media and pushes for further exploration of more inclusive dermatologic imagery. 展开更多
关键词 PSORIASIS Internet Skin tone bias Image search Global
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A dynamic DRASTIC-based approach for multi-hazard groundwater vulnerability mapping
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作者 Muhammad Umar Akbar Ali Mirchi +3 位作者 Arfan Arshad Abubakarr Mansaray Ahsan Saif Ullah Kaveh Madani 《Geoscience Frontiers》 2025年第5期403-425,共23页
This study advances the DRASTIC groundwater vulnerability assessment framework by integrating a multi-hazard groundwater index(MHGI)to account for the dynamic impacts of diverse anthropogenic activities and natural fa... This study advances the DRASTIC groundwater vulnerability assessment framework by integrating a multi-hazard groundwater index(MHGI)to account for the dynamic impacts of diverse anthropogenic activities and natural factors on both groundwater quality and quantity.Incorporating factors such as population growth,agricultural practices,and groundwater extraction enhances the framework’s ability to capture multi-dimensional,spatiotemporal changes in groundwater vulnerability.Additional improvements include refined weighting and rating scales for thematic layers based on available observational data,and the inclusion of distributed recharge.We demonstrate the practical utility of this dynamic DRASTIC-based framework through its application to the agro-urban regions of the Irrigated Indus Basin,a major groundwater-dependent agricultural area in South Asia.Results indicate that between 2005 and 2020,54%of the study area became highly vulnerable to pollution.The MHGI revealed a 13%decline in potential groundwater storage and a 25%increase in groundwater-stressed zones,driven primarily by population growth and intensive agriculture.Groundwater vulnerability based on both groundwater quality and quantity dimensions showed a 19%decline in areas of low to very low vulnerability and a 6%reduction in medium vulnerability zones by 2020.Sensitivity analyses indicated that groundwater vulnerability in the region is most influenced by groundwater recharge(42%)and renewable groundwater stress(38%).Validation with in-situ data yielded area under the curve values of 0.71 for groundwater quality vulnerability and 0.63 for MHGI.The framework provides valuable insights to guide sustainable groundwater management,safeguarding both environmental integrity and human well-being. 展开更多
关键词 GROUNDWATER DRASTIC Multi-hazard index Groundwater quality and quantity Vulnerability mapping SUSTAINABILITY
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The Solar Close Observations and Proximity Experiments(SCOPE)mission 被引量:1
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作者 Jun Lin Jing Feng +31 位作者 Zhenhua Ge Jiang Tian Yuhao Chen Xin Cheng Hui Tian Jiansen He Alexei Pevtsov Haisheng Ji Shangbin Yang ParidaHashim Bin Zhou Yiteng Zhang Shenyi Zhang Xi Lu Yuan Yuan Liu Liu Haoyu Wang Hu Jiang Lei Deng Xingjian Shi Lin Ma Jingxing Wang Shanjie Huang Xiaoshi Zhang Hao Yang Zhonghua Yao He Zhang Yuanming Miao Lei Ni Zhixing Mei Jing Ye Yan Li 《Astronomical Techniques and Instruments》 2025年第3期148-174,共27页
The Solar Close Observations and Proximity Experiments(SCOPE)mission will send a spacecraft into the solar atmosphere at a low altitude of just 5 R☉from the solar center.It aims to elucidate the mechanisms behind sol... The Solar Close Observations and Proximity Experiments(SCOPE)mission will send a spacecraft into the solar atmosphere at a low altitude of just 5 R☉from the solar center.It aims to elucidate the mechanisms behind solar eruptions and coronal heating,and to directly measure the coronal magnetic field.The mission will perform in situ measurements of the current sheet between coronal mass ejections and their associated solar flares,and energetic particles produced by either reconnection or fast-mode shocks driven by coronal mass ejections.This will help to resolve the nature of reconnections in current sheets,and energetic particle acceleration regions.To investigate coronal heating,the mission will observe nano-flares on scales smaller than 70 km in the solar corona and regions smaller than 40 km in the photosphere,where magnetohydrodynamic waves originate.To study solar wind acceleration mechanisms,the mission will also track the process of ion charge-state freezing in the solar wind.A key achievement will be the observation of the coronal magnetic field at unprecedented proximity to the solar photosphere.The polar regions will also be observed at close range,and the inner edge of the solar system dust disk may be identified for the first time.This work presents the detailed background,science,and mission concept of SCOPE and discusses how we aim to address the questions mentioned above. 展开更多
关键词 Solar activities Coronal magnetic field In situ measurements Deep space mission Thermal protection system Thermal-electric conversion
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“00.7”北京特大暴雨模拟中气象资料同化作用的评估 被引量:39
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作者 张朝林 陈敏 +2 位作者 Kuo Ying-Hwa 范水勇 仲跻芹 《气象学报》 CAS CSCD 北大核心 2005年第6期922-932,共11页
针对2000年7月4~5日北京地区的一次特大暴雨过程(24 h降水量达240 mm),文中利用MM5/WRF三维变分系统和MM5非静力模式,对此次特大暴雨过程中的各种气象监测资料(地基GPS大气柱水汽含量、常规探空、高空测风、地面常规观测和地面自动气象... 针对2000年7月4~5日北京地区的一次特大暴雨过程(24 h降水量达240 mm),文中利用MM5/WRF三维变分系统和MM5非静力模式,对此次特大暴雨过程中的各种气象监测资料(地基GPS大气柱水汽含量、常规探空、高空测风、地面常规观测和地面自动气象站)的同化作用通过观测系统数值试验进行了评估.结果表明:与传统的客观分析方案相比较,MM5/WRF三维变分同化系统可直接引入非常规地基GPS大气柱水汽含量监测资料,提供更好的大气初始分析场.在三维变分同化方案下,各种大气监测资料均对改进此次特大暴雨模拟有不同程度的贡献,其中,常规探空和高空测风监测资料对改进预报结果的影响最大,地面常规观测和地面自动气象站观测资料作用次之,地基GPS大气柱水汽含量资料在与其他大气监测资料相互优势互补后,可很好地改善模式大气的分析质量,通过三维变分同化技术在区域数值天气预报模式初始场中引入地基GPS大气水汽监测网资料,使此次强降水个例的6 h和24 h测站降水预报的TS评分值在1,5,10和20 mm预报检验阈值下分别提高了1%~8%.研究结果对利用三维变分数值系统,评估气象监测网资料在改进高影响天气事件预报中的作用有借鉴意义. 展开更多
关键词 三维变分资料同化 全球定位系统 暴雨 观测系统试验 数值预报
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天津大气污染物日变化特征的WRF-Chem数值模拟 被引量:39
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作者 韩素芹 冯银厂 +4 位作者 边海 铁学熙 解以扬 李向津 孙玫玲 《中国环境科学》 EI CAS CSCD 北大核心 2008年第9期828-832,共5页
利用大气化学完全耦合模式WRF-Chem对天津市环境空气中特征污染物CO、NOx、O3、PM2.5的时间变化规律和空间分布特征进行了数值模拟研究,并与实际观测资料进行了对比.结果表明,天津市CO、NOx、O3、PM2.5具有明显的时空变化特征:O3浓度在... 利用大气化学完全耦合模式WRF-Chem对天津市环境空气中特征污染物CO、NOx、O3、PM2.5的时间变化规律和空间分布特征进行了数值模拟研究,并与实际观测资料进行了对比.结果表明,天津市CO、NOx、O3、PM2.5具有明显的时空变化特征:O3浓度在中午出现最高值,夜间浓度较低;NOx、O3、PM2.5在晚上和清晨出现高浓度,午后至傍晚浓度较低.O3在空间分布上表现为中午市区比郊区浓度高,夜间郊区浓度高.其他污染物则均表现为市区浓度高于郊区.在当日东北风情况下,周边地区对天津市污染的影响较小,4类污染物主要是受本地源的影响. 展开更多
关键词 WRF-Chem模式 PM2.5 NOx CO O3 数值模拟
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高分辨率WRF三维变分同化在北京地区降水预报中的应用 被引量:51
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作者 范水勇 郭永润 +6 位作者 陈敏 仲跻芹 楚艳丽 王薇 黄向宇 王迎春 郭英华 《高原气象》 CSCD 北大核心 2008年第6期1181-1188,共8页
为迎接2008年北京奥运会,改进北京地区的天气预报,建立了一个基于三重嵌套区域(27/9/3 km)的WRF三维变分同化(WRFVar)和WRF模式的高分辨率快速更新循环同化预报(Rapid-Up-date Cycle)系统,并针对2006年8月1日发生在北京地区的强对流天... 为迎接2008年北京奥运会,改进北京地区的天气预报,建立了一个基于三重嵌套区域(27/9/3 km)的WRF三维变分同化(WRFVar)和WRF模式的高分辨率快速更新循环同化预报(Rapid-Up-date Cycle)系统,并针对2006年8月1日发生在北京地区的强对流天气进行了一系列数值试验,结果表明:高分辨率的快速更新循环系统很好地预报出了此次强降水过程;在WRF三维变分同化里调节背景场误差和观测误差,提高了降水预报的效果;插值得出的3 km背景场误差可以作为一个合理的近似在3 km分辨率的WRFVar中使用,用户可以不必积累高分辨率的预报场去计算背景场误差,从而节省大量计算资源。3 h频次的RUC已经能满足预报要求,更高频次(1 h)的RUC并没有导致预报的进一步提高。 展开更多
关键词 北京地区 WRF三维变分同化 WRF模式 高分辨率 快速更新循环
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北京精细下垫面信息引入对暴雨模拟的影响 被引量:50
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作者 张朝林 苗世光 +1 位作者 李青春 CHEN Fei 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2007年第5期1373-1382,共10页
首先根据2000年环北京实际的精细下垫面布局资料(500m分辨率),按美国USGS陆面资料分类标准(25类)对其提供的全球30 s经纬分辨率(≈1 km)下垫面分类资料进行了更新设计.进而针对一个北京夏季暴雨过程,利用10:3.3km双向双重嵌套的MM5V3.6-... 首先根据2000年环北京实际的精细下垫面布局资料(500m分辨率),按美国USGS陆面资料分类标准(25类)对其提供的全球30 s经纬分辨率(≈1 km)下垫面分类资料进行了更新设计.进而针对一个北京夏季暴雨过程,利用10:3.3km双向双重嵌套的MM5V3.6-Noah LSM陆气耦合模式进行24h数值对比试验,研究了北京精细下垫面信息引入对暴雨的影响.分析表明:新设计的陆面资料更真实地反映了环北京区域的下垫面结构,尤其针对北京城区面积迅增特征;同时还修正了原资料将亚洲中纬度区域落叶阔叶林下垫面类型归属为热带(或亚热带)稀疏大草原类型的问题.其在数值天气模式中的引入会对短期暴雨过程的发生发展产生重要影响.对此次暴雨主要降水中心的模拟,12h差值分布范围远达30km以上,中心值相对差异可达30%.研究发现在城市下垫面和大气相互间存在一个重要的相互影响机制,即由于城区面积的扩大会导致自然植被减少,进而会减少地表蒸发及相应局地大气水分供应、加深边界层高度并增强大气水汽混合,这不利于降水的发生发展. 展开更多
关键词 陆面物理过程 暴雨 下垫面变化 数值天气预报 城市气象
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