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Book Review: Introduction to Artificial Intelligence. Ed. by Fei Wu and Yunhe Pan
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作者 fei wu 《Frontiers of Digital Education》 2024年第3期272-273,共2页
Artificial intelligence(AI)is a strategic technology and an important driving force leading the scientific and technological revolution and industrial change.AI has the potential to enhance every technology as it rese... Artificial intelligence(AI)is a strategic technology and an important driving force leading the scientific and technological revolution and industrial change.AI has the potential to enhance every technology as it resembles enabling technologies like the combustion engine or electricity.We believe the nature of AI is interdisciplinary.In other words,the power of AI lies in augmenting its ability to accelerate research exponentially and the possibilities are endless. 展开更多
关键词 driving STRATEGIC ELECTRICITY
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Emerging nanoparticle-based strategies to provide therapeutic benefits for stroke
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作者 Javaria Sundus Nashwa Amin +6 位作者 Irum Naz Abbasi fei wu Azhar BHussien Benson OA Botchway Suhong Ye Qining Yang Marong Fang 《Neural Regeneration Research》 2026年第5期1764-1782,共19页
Functional neurological recovery remains the primary objective when treating ischemic stroke.However,current therapeutic approaches often fall short of achieving optimal outcomes.One of the most significant challenges... Functional neurological recovery remains the primary objective when treating ischemic stroke.However,current therapeutic approaches often fall short of achieving optimal outcomes.One of the most significant challenges in stroke treatment is the effective delivery of neuroprotective agents across the blood–brain barrier to ischemic regions within the brain.The blood–brain barrier,while essential for protecting the brain from harmful substances,also restricts the passage of many therapeutic compounds,thus limiting their efficacy.In this review,we summarizes the emerging role of nanoparticle-based therapies for the treatment of ischemic stroke and investigate their potential to revolutionize drug delivery,enhance neuroprotection,and promote functional recovery.Recent advancements in nanotechnology have led to the development of engineered nanoparticles specifically designed to overcome the blood–brain barrier,thus enabling the targeted delivery of therapeutic agents directly to the affected brain areas.Preclinical studies have demonstrated the remarkable potential of nanoparticle-based therapies to activate key neuroprotective pathways,such as the phosphoinositide 3-kinase/protein kinase B/c AMP response element-binding protein signaling cascade,which is crucial for neuronal survival,synaptic plasticity,and post-stroke recovery.By modulating these pathways,nanoparticles could mitigate neuronal damage,reduce inflammation,and promote tissue repair.Furthermore,nanoparticles offer a unique advantage by enabling multimodal therapeutic strategies that simultaneously target multiple pathological mechanisms of ischemic stroke,including oxidative stress,neuroinflammation,and apoptosis.This multifaceted approach enhances the overall efficacy of treatment,addressing the complex and interconnected processes that contribute to stroke-related brain injury.Surface modifications,such as functionalization with specific ligands or targeting molecules,further improve the precision of drug delivery,enhance targeting specificity,and prolong systemic circulation,thereby optimizing therapeutic outcomes.Nanoparticlebased therapeutics represent a paradigm shift for the management of stroke and provide a promising avenue for reducing post-stroke disability and improving the outcomes of long-term rehabilitation.By combining targeted drug delivery with the ability to modulate critical neuroprotective pathways,nanoparticles hold the potential to transform the treatment landscape for ischemic stroke.However,while preclinical data are highly encouraging,significant challenges remain in translating these advancements into clinical practice.Further research is needed to refine nanoparticle designs,optimize their safety profiles,and ensure their scalability for widespread application.Rigorous clinical trials are essential to validate their efficacy,assess long-term biocompatibility,and address potential off-target effects.The integration of interdisciplinary approaches,combining insights from nanotechnology,neuroscience,and pharmacology,will be critical if we are to overcome these challenges.Ultimately,nanoparticle-based therapies offer a foundation for innovative,precision-based treatments that could significantly improve outcomes for stroke patients,thus paving the way for a new era in stroke care and neurological rehabilitation. 展开更多
关键词 blood–brain barrier drug delivery systems ischemic stroke NANOMEDICINE nanoparticles NEUROINFLAMMATION NEURONS NEUROPROTECTION oxidative stress phosphatidylinositol 3-kinases
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“互塑”之弈:中国生成式人工智能技术形象的国际新闻话语建构 被引量:1
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作者 高北晨 吴飞 《新媒体与社会》 2025年第1期30-51,456,457,共24页
本研究聚焦中国生成式AI技术在国际主流新闻媒体上的形象构建,旨在探讨国际新闻话语如何通过不同策略塑造中国技术的国际认知,以及建构中国生成式AI技术形象的国际主流媒体话语博弈。本研究采用扎根理论,分析道琼斯数据库Factiva中的301... 本研究聚焦中国生成式AI技术在国际主流新闻媒体上的形象构建,旨在探讨国际新闻话语如何通过不同策略塑造中国技术的国际认知,以及建构中国生成式AI技术形象的国际主流媒体话语博弈。本研究采用扎根理论,分析道琼斯数据库Factiva中的3015篇新闻文本,通过三级编码提炼出技术发展者、市场竞争者、关系链接者、安全威胁者、技术受制者五种主要技术形象。研究发现,中国生成式AI在正面形象方面被构建为技术实力和关系桥接的象征,但同时在负面形象被描绘为潜在威胁和技术受制方。研究在进一步分析国际主流新闻话语在构建中国生成式AI技术形象的策略机理中,着力揭示国际话语场域中关于技术价值、权力和契约的多重博弈。研究结论表明,国际舆论对中国生成式AI的形象构建不仅反映了中西方的技术认知分歧,也展现了国际科技发展领域的内在张力。 展开更多
关键词 生成式AI 技术形象 国际新闻 话语博弈 价值张力
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鳄蜥的微生境选择特征及保护启示
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作者 沈君瀚 高海洋 +5 位作者 孙松 吴飞 何南 王鹤 华彦 武正军 《生物多样性》 北大核心 2025年第11期195-206,共12页
明确濒危物种的微生境选择特征是为其制定科学保护策略的基础。鳄蜥(Shinisaurus crocodilurus)是全球濒危物种,野外种群数量仅剩1,500只左右。本研究于广东罗坑鳄蜥国家级自然保护区,针对鳄蜥集中分布的溪沟开展微生境样方调查,系统分... 明确濒危物种的微生境选择特征是为其制定科学保护策略的基础。鳄蜥(Shinisaurus crocodilurus)是全球濒危物种,野外种群数量仅剩1,500只左右。本研究于广东罗坑鳄蜥国家级自然保护区,针对鳄蜥集中分布的溪沟开展微生境样方调查,系统分析了鳄蜥的微生境选择特征。随机森林模型分析以及袋外误差计算表明栖枝密度、溪流深度、溪流沙覆盖比、郁闭度、溪流流速和溪流宽度是影响鳄蜥利用微生境的重要变量,并具有特定的生态阈值。广义线性混合效应最终模型表明,栖枝密度、溪流深度、郁闭度和溪流宽度与鳄蜥出现概率呈显著正相关;其中,栖枝密度为影响鳄蜥出现概率的首要因子,溪流深度次之;郁闭度虽独立贡献率较低,然其作用不可或缺,是基础性影响因子;而溪流宽度则为边缘影响因子。多模型分析结果综合表明,鳄蜥尤其偏好高栖枝密度的微生境,可能与其获取庇护和食物资源的需求相关。研究建议,在鳄蜥保护中应以提高栖枝密度构建多层次庇护网络作为首要目标,同时通过改善水文环境和提高乔木郁闭度等措施,为鳄蜥种群提供更适宜的生存环境。 展开更多
关键词 微生境选择 随机森林模型 广义线性混合模型 栖枝密度 鳄蜥
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超声速单/双矩形喷流气动噪声数值研究
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作者 查君培 陈保 +1 位作者 吴飞 李伟鹏 《航空学报》 北大核心 2025年第14期88-102,共15页
矩形喷管因其优异的推力矢量控制和隐身性能在军用飞机设计中日益受到重视,而双喷流耦合干扰是一个很有吸引力的气动声学问题,其噪声特征和发声机理仍不十分明确。采用高精度数值格式和隐式大涡模拟方法,对超声速欠膨胀单/双矩形喷流开... 矩形喷管因其优异的推力矢量控制和隐身性能在军用飞机设计中日益受到重视,而双喷流耦合干扰是一个很有吸引力的气动声学问题,其噪声特征和发声机理仍不十分明确。采用高精度数值格式和隐式大涡模拟方法,对超声速欠膨胀单/双矩形喷流开展数值仿真研究,预测的单喷流流声特性与实验结果吻合较好。研究结果表明,当双喷流间距为3.5h时,双喷流相互作用对喷流内部结构与剪切层发展的影响并不显著,但单/双喷流总声压级分布和声指向特征存在明显差异,与单喷流相比,双喷流啸声频率略微减小,啸声强度有较大幅度提升。采用傅里叶模态分解和谱本征正交分解提取流场相干结构,单喷流中呈现螺旋模态,而双喷流中切换为沿短轴方向的摆动模态,且两喷流摆动相位同步。模态分析进一步指出了啸声频率和强度上的变化与声源位置偏移的关联。 展开更多
关键词 矩形喷管 双喷流耦合 气动噪声 谱本征正交分解 大涡模拟
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Knowledge-Empowered,Collaborative,and Co-Evolving AI Models:The Post-LLM Roadmap 被引量:1
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作者 fei wu Tao Shen +17 位作者 Thomas Back Jingyuan Chen Gang Huang Yaochu Jin Kun Kuang Mengze Li Cewu Lu Jiaxu Miao Yongwei Wang Ying Wei Fan wu Junchi Yan Hongxia Yang Yi Yang Shengyu Zhang Zhou Zhao Yueting Zhuang Yunhe Pan 《Engineering》 2025年第1期87-100,共14页
Large language models(LLMs)have significantly advanced artificial intelligence(AI)by excelling in tasks such as understanding,generation,and reasoning across multiple modalities.Despite these achievements,LLMs have in... Large language models(LLMs)have significantly advanced artificial intelligence(AI)by excelling in tasks such as understanding,generation,and reasoning across multiple modalities.Despite these achievements,LLMs have inherent limitations including outdated information,hallucinations,inefficiency,lack of interpretability,and challenges in domain-specific accuracy.To address these issues,this survey explores three promising directions in the post-LLM era:knowledge empowerment,model collaboration,and model co-evolution.First,we examine methods of integrating external knowledge into LLMs to enhance factual accuracy,reasoning capabilities,and interpretability,including incorporating knowledge into training objectives,instruction tuning,retrieval-augmented inference,and knowledge prompting.Second,we discuss model collaboration strategies that leverage the complementary strengths of LLMs and smaller models to improve efficiency and domain-specific performance through techniques such as model merging,functional model collaboration,and knowledge injection.Third,we delve into model co-evolution,in which multiple models collaboratively evolve by sharing knowledge,parameters,and learning strategies to adapt to dynamic environments and tasks,thereby enhancing their adaptability and continual learning.We illustrate how the integration of these techniques advances AI capabilities in science,engineering,and society—particularly in hypothesis development,problem formulation,problem-solving,and interpretability across various domains.We conclude by outlining future pathways for further advancement and applications. 展开更多
关键词 Artificial intelligence Large language models Knowledge empowerment Model collaboration Model co-evolution
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Development Trends and Priority Research Fields of Electrochemical Discipline in the 15th Five Year Plan Period
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作者 Lin Zhuang Wen-Bin Cai +36 位作者 Heng-Xing Ji Qing Li Gong-Wei Wang Sen Xin Qing Zhao Fang-Yi Cheng Yu-Guo Guo Lan-Qun Mao Yang Tian fei wu Li-Min Zhang Yan Xiang Jin-Song Hu Rui Cao Li Xiao Hua-Bing Tao Wei Xing Dong-Ping Zhan Hong-Gang Liao Mei-Ling Xiao Bin Ren Zhang-Quan Peng Rui Wen Xiang Wang Yue-Feng Song Hou-Fu Lv Bao-Yu Xia Guo-Xiong Wang Jun Cheng Zhi-Pan Liu Min Zhou Bing Huang Cun-Pu Li Yu-Qin Zou Shuang-Yin Wang Hai-Bo Lin Zi-Dong Wei 《电化学(中英文)》 北大核心 2025年第10期84-115,共32页
In fulfillment of the national science-and-technology development agenda, the Department of Chemical Sciences of the National Natural Science Foundation of China (NSFC) convened the Strategic Symposium on the Fifteent... In fulfillment of the national science-and-technology development agenda, the Department of Chemical Sciences of the National Natural Science Foundation of China (NSFC) convened the Strategic Symposium on the Fifteenth FiveYear (20262030) Development Plan for Electrochemistry held in Xiamen on 29 August, 2025-the culminating year of the Fourteenth Five-Year (2021-2025) Development Plan. More than forty leading experts in the field of electrochemistry participated with spanning nine thematic fronts: Interfacial Electrocatalysis, Interfacial Electrochemistry for Energy Storage, Bioelectrochemistry, Electrochemistry of Hydrogen Energy, Electrochemical Micro-/Nano-Manufacturing, Operando Electrochemical Characterization, Electro-Thermal Coupling Catalysis, Theoretical and Computational Electrochemistry,and Electrochemical Synthesis. The forum assembled China's foremost electrochemical expertise to blueprint high-quality disciplinary growth for the coming five-year period, thereby serving overarching national strategic needs and sharpening the international competitiveness of Chinese electrochemistry.This paper is presented to highlight the strategic needs and priority areas for the next five years (2026-2030) based on this symposium. The development status of basic research and applied basic research in China's electrochemistry field is systematically reviewed. The in-depth analyses of the existing problems and key challenges in the research and development of electrochemistry related fields are outlined, and the frontier research areas and development trends in the next 5-10 years by integrating national major strategic needs are discussed, which will further promote the academic community to reach a clearer consensus. The proposed strategic roadmap is intended to accelerate a sharpened community consensus, propel the discipline toward high-quality advancement, and furnish a critical reference for building China into a world-leading science and technology power. 展开更多
关键词 energy storage ELECTROCHEMISTRY strategic symposium chemical sciences interfacial electrocatalysis hydrogen energy BIOELECTROCHEMISTRY electrochemical micro nano manufacturing
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Limitations and enhancement opportunities for variceal rebleeding prediction model in patients with cirrhosis
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作者 Guang-Bin Chen fei wu +1 位作者 Rong-Mei Tang Long-Jiang Chen 《World Journal of Gastroenterology》 2025年第8期161-163,共3页
A multicenter study recently published introduced a novel prognostic model for predicting esophagogastric variceal rebleeding after endoscopic treatment in patients with cirrhosis.The model incorporated six readily av... A multicenter study recently published introduced a novel prognostic model for predicting esophagogastric variceal rebleeding after endoscopic treatment in patients with cirrhosis.The model incorporated six readily available clinical variables—albumin level,aspartate aminotransferase level,white blood cell count,ascites,portal vein thrombosis,and bleeding signs—and demonstrated promising predictive performance.However,limitations,including the retrospective design and exclusion of patients with hepatocellular carcinoma,may affect the generaliz-ability of the model.Additionally,further improvement is needed in the model’s discrimination between intermediate-and high-risk groups in external.Prospec-tive validation and inclusion of additional variables are recommended to enhan-ce predictive accuracy across diverse clinical scenarios. 展开更多
关键词 Prognostic model Liver cirrhosis Variceal rebleeding Risk stratification Endoscopic treatment Portal hypertension Clinical prediction
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Nutrient recharge effect of Yangtze River to tributary backwater area in Three Gorges Reservoir,China
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作者 Wei Yin Chao Wang +6 位作者 Shidian wu fei wu Xiaokang Xin Fengpeng Bai feixi Zhao Haiyan Jia Hong Zhang 《Journal of Environmental Sciences》 2025年第8期426-435,共10页
Interaction between the Yangtze River and its tributaries in the Three Gorges Reservoir has an important influence on tributary algal blooms.Taking the Xiaojiang River as a typical tributary,a binary mixing model used... Interaction between the Yangtze River and its tributaries in the Three Gorges Reservoir has an important influence on tributary algal blooms.Taking the Xiaojiang River as a typical tributary,a binary mixing model used stable isotopes of hydrogen and oxygen to quantitatively analyze the water contribution and nutrient source structure of the tributary backwater area.Results showed that the isotope content(δD:−54.7‰,δ^(18)O−7.8‰)in the Yangtze River was higher than that in the tributaries(δD:−74.2‰,δ^(18)O−17.0‰)in the non-flood season and lower than that in the tributaries in the flood season.The Yangtze River contributed more than 50%water volume of the tributary backwater area in the non-flood season.The total nitrogen and total phosphorus concentrations in the backwater area were estimated based on water contribution ratio,and the results were in good agreement with the monitoring results.Load estimation showed that the nitrogen and phosphorus contribution ratio of the Yangtze River to the tributary backwater area was approximately 40%-80%in the non-flood season,and approximately 20%-40%in the flood season,on average.This study showed that the interaction between the Xiaojiang River and the Yangtze River is significant,and that Yangtze River recharge is an important source of nutrients in the Xiaojiang backwater area,which may play a driving role in Xiaojiang River algal blooms. 展开更多
关键词 Yangtze River TRIBUTARY INTERACTION Three gorges reservoir NUTRIENT Recharge effect
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Recommendations of Stable Mg,Si,V,Fe,Cu,Zn,Rb,Sr,Ag,Cd,Ba,and U Isotope Compositions for Multiple Geological References
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作者 Jinting Kang Xuqi Chen +16 位作者 Xi Deng Yuan Fang Haichuan Jiang Chengyihong Liu Cuihua Luo Xing Li Yuchao Lin Zhaoqi Ren Jiaru Sheng Xue Tang Liyi Xu Jinyi Yan Yaqi Zhang Zhengyu Hou fei wu Huimin Yu Fang Huang 《Journal of Earth Science》 2025年第4期1408-1424,共17页
The Metal Stable Isotope Geochemistry Laboratory(MSIGL)at the University of Science and Technology of China has developed state-of-the-art analytical methods for twelve stable isotope systems,including Mg,Si,V,Fe,Cu,Z... The Metal Stable Isotope Geochemistry Laboratory(MSIGL)at the University of Science and Technology of China has developed state-of-the-art analytical methods for twelve stable isotope systems,including Mg,Si,V,Fe,Cu,Zn,Rb,Sr,Ag,Cd,Ba,and U.Geological and biological samples were first digested by acid dissolution or alkali dissolution.The target element was subsequently purified by the column chromatography method.A Neptune Plus MC-ICP-MS was used to measure isotope compositions and the isotope bias caused during measurements was calibrated by standard bracketing and/or the double spike method.The analytical procedure was carefully checked to ensure the high precision and accuracy of the data.Here,we summarized the protocol of these established methods and compiled the standard data measured at our lab as well as those reported in literature.This comprehensive dataset can serve as a reliable benchmark for calibration,method validation,and quality assurance in metal stable isotope analyses. 展开更多
关键词 non-traditional stable isotope metal stable isotope analytical methods MC-ICP-MS standards geological references
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Level Set Topology Optimization with Autonomous Hole Formation Using Material Removal Scheme of SIMP
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作者 fei wu Ziyang Zeng +2 位作者 Kunliang Xie Yuqiang Liu Jiang Ding 《Computer Modeling in Engineering & Sciences》 2025年第11期1689-1710,共22页
The level set method(LSM)is renowned for producing smooth boundaries and clear geometric representations,facilitating integration with CAD environments.However,its inability to autonomously generate new holes during o... The level set method(LSM)is renowned for producing smooth boundaries and clear geometric representations,facilitating integration with CAD environments.However,its inability to autonomously generate new holes during optimization makes the results highly dependent on the initial design.Although topological derivatives are often introduced to enable hole nucleation,their conversion into effective shape derivatives remains challenging,limiting topological evolution.To address this,a level set topology optimization method with autonomous hole formation(LSM-AHF)is proposed,integrating the material removal mechanism of the SIMP(Solid Isotropic Material with Penalization)method into the LSM framework.First,an initial structure is generated by adjusting the judgment threshold,and a binary thresholding algorithm is subsequently employed to obtain a clear and well-defined geometry.The structural boundaries of this geometry are then identified and used to construct a signed distance field,which serves as the initial level set function.To ensure smooth transitions across material interfaces and enhance numerical stability,Gaussian filtering is subsequently applied to the distance field.Numerical results demonstrate that LSMAHF effectively enables hole nucleation without manual initialization and improves topology change,addressing the respective limitations of conventional LSM and SIMP methods. 展开更多
关键词 SIMP LSM judgment threshold boundary distance model autonomous hole formation
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Polycarbonyl conjugated porous polyimide as anode materials for high performance sodium-ion batteries
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作者 Liangju Zhao Shiyu Qin +7 位作者 fei wu Limin Zhu Qing Han Lingling Xie Xuejing Qiu Hongliang Wei Lanhua Yi Xiaoyu Cao 《Chinese Chemical Letters》 2025年第8期498-504,共7页
Conjugated microporous polymers(CMPs)have attracted considerable attention as potential organic anode materials for sodium-ion batteries(SIBs)due to their flexible chemical structure,high porosity,environmental friend... Conjugated microporous polymers(CMPs)have attracted considerable attention as potential organic anode materials for sodium-ion batteries(SIBs)due to their flexible chemical structure,high porosity,environmental friendliness,and cost effectiveness.However,the inherent shortcomings of organic electrodes,such as low conductivity,high solubility in electrolyte,narrow material utilization,etc.,limit their further development.In this work,we successfully prepared a novel porous polyimide PPD containing multicarbonyl active centers via the polycondensation of pyromellitic dianhydride(PMDA)and2,6-diaminoanthraquinone(DAAQ).The stable conjugated structure and multiple redox centers give the polymer high reversible specific capacity(244.6 m Ah/g after 100 cycles at 100 m A/g),ultra-long cycle stability(100.7 m Ah/g after 2000 cycles at 1.0 A/g),and predominant rate capability.Meanwhile,the sodium storage mechanism of the electrode materials during the charging and discharging process is investigated by ex-situ XPS/FTIR analysis.Due to the exceptional electrochemical properties and simple synthesis method,this work may shed light on the preparation of polyimide-based anodes for high specific capacity and rate capability secondary batteries. 展开更多
关键词 Sodium-ion batteries Porous polyimide Polycarbonyl Organic materials Anodes
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A navigation system for permanent-magnet-actuated microswarm
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作者 Jingjie Zhou Side Zeng +1 位作者 fei wu Fangzhi Mou 《Nanotechnology and Precision Engineering》 2025年第4期106-117,共12页
Micro/nanorobots have significant potential applications in biomedicine.However,their small size and the need for intricate control make long-distance navigation of microswarms composed of such robots challenging in c... Micro/nanorobots have significant potential applications in biomedicine.However,their small size and the need for intricate control make long-distance navigation of microswarms composed of such robots challenging in complex environments.To address this problem,we have developed a permanent-magnet-actuated microswarm navigation system to achieve precise control of micro/nanorobots in complex fluid environments.The controlled microswarm is composed of monodisperse Fe_(3)O_(4)@PVP nanoclusters synthesized using the polyol method.These nanoclusters can self-assemble into highly controllable microswarm structures under a rotating magnetic field and are then guided by the robotic system for precise navigation.The system uses visual positioning and motion control to enable real-time dynamic navigation.In experiments,it successfully performed autonomous navigation over a 55 mm distance in a transparent channel,with flow rates ranging from 0 to 10 mm/s.It completed the task in 132 s at an average speed of over 0.45 mm/s,with an average trajectory tracking error of only 0.28 mm.These results demonstrate excellent path accuracy and stability under various flow rate conditions,validating the system’s adaptability and efficiency in fluid environments and highlighting its potential for biomedical applications.This study offers a robust and versatile platform for expanding micro/nanorobot applications in biomedicine. 展开更多
关键词 Permanent magnet Microswarm Fluid environment Navigation system
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Damage behavior of red sandstone subjected to multi-stage constantamplitude cyclic loading
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作者 Shuo Gao fei wu +2 位作者 Renbo Gao Cunbao Li Jie Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第10期6548-6570,共23页
Cyclic changes in the internal pressure of compressed air energy storage reservoirs in abandoned coal mines result in complex alternating loads on the rocks surrounding the energy storage reservoirs.These complex alte... Cyclic changes in the internal pressure of compressed air energy storage reservoirs in abandoned coal mines result in complex alternating loads on the rocks surrounding the energy storage reservoirs.These complex alternating loads can be regarded as multi-stage constant-amplitude cyclic loads following simplification.In this paper,the mechanical responses and acoustic emission(AE)characteristics of red sandstone with five bedding dip angles(0°,30°,45°,60°,and 90°)under such loads are investigated,and the damage evolution processes of the five specimens are revealed from both quantitative and microscopic perspectives.The results show that the fatigue deformation characteristics of the specimens are affected by the bedding dip angle.Under cyclic loads,the axially irreversible plastic deformations of the rocks increase,their elastic stiffness increases,their crack volumetric strain increases and then decreases,and their AE cumulative count/energy curves exhibit a ladder shape.A damage evolution model based on the crack volumetric strain is proposed,and the damage evolution process is divided into two stages:a rapid increase stage and a tendency toward stabilization stage.Through cluster analysis,the AE events are used to classify the damage into three categories:small-sized localized damage,large-sized tensile damage,and large-sized shear damage.Finally,the MohreCoulomb criterion is applied to analyze the relationship between the failure modes of the red sandstone specimens and the dip angle of the bedding.The results of this study will help to predict the stability and safety of compressed air energy storage reservoirs in abandoned coal mines. 展开更多
关键词 Cyclic loads Bedding dip angle Red sandstone Damage evolution
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Fatigue properties and constitutive model of Jintan salt rock subjected to complex cyclic loading
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作者 Qingchuan He Jianfeng Liu +5 位作者 fei wu Cunbao Li Jie Chen Renbo Gao Chunfeng Ye Shijie Zhu 《International Journal of Mining Science and Technology》 2025年第1期121-133,共13页
Salt cavern energy storage technology contributes to energy reserves and renewable energy scale-up.This study focuses on salt cavern gas storage in Jintan to assess the long-term stability of its surrounding rock unde... Salt cavern energy storage technology contributes to energy reserves and renewable energy scale-up.This study focuses on salt cavern gas storage in Jintan to assess the long-term stability of its surrounding rock under frequent operation.The fatigue test results indicate that stress holding significantly reduces fatigue life,with the magnitude of stress level outweighing the duration of holding time in determining peak strain.Employing a machine learning approach,the impact of various factors on fatigue life and peak strain was quantified,revealing that higher stress limits and stress holding adversely impact the fatigue index,whereas lower stress limits and rate exhibit a positive effect.A novel fatigue-creep composite damage constitutive model is constructed,which is able to consider stress magnitude,rate,and stress holding.The model,validated through multi-path tests,accurately captures the elasto-viscous behavior of salt rock during loading,unloading,and stress holding.Sensitivity analysis further reveals the time-and stress-dependent behavior of model parameters,clarifying that strain changes stem not only from stress variations but are also influenced by alterations in elasto-viscous parameters.This study provides a new method for the mechanical assessment of salt cavern gas storage surrounding rocks. 展开更多
关键词 Salt cavern gas storage Cyclic loading Fatigue characteristics Constitutive model
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Damage evolution and failure modes of coal-concrete composites with varying height ratios under cyclic loading
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作者 Renbo Gao fei wu +3 位作者 Cunbao Li Chunfeng Ye Qingchuan He Heping Xie 《International Journal of Mining Science and Technology》 2025年第7期1093-1106,共14页
To ensure the safe implementation of underground reservoirs in abandoned coal mines,this study explores the mechanical behavior and failure mechanisms of coal-concrete composite structures under staged cyclic loading.... To ensure the safe implementation of underground reservoirs in abandoned coal mines,this study explores the mechanical behavior and failure mechanisms of coal-concrete composite structures under staged cyclic loading.Specimens with coal-to-concrete height ratios ranging from 0.5:1 to 3:1 were tested,with damage evolution continuously monitored using acoustic emission techniques.Results indicate that while the peak strength of pure materials decreases by approximately 1 MPa under cyclic stress compared to uniaxial compression,composite specimens exhibit strength enhancements exceeding 5 MPa.However,the peak strength of composite specimens decreases with increasing coal height,from 30 MPa at CR0.5 to 20 MPa at CR3.0.The damage state was assessed using the dynamic elastic strain energy index and Felicity ratio,which revealed that composite specimens are more prone to early damage accumulation.Spatial acoustic emission localization further reveals distinct failure modes across specimens with varying height ratios.To elucidate these differences,interfacial effects were incorporated into a modified twin-shear unified strength theory.The refined model accurately predicts the internal strength distribution and failure characteristics of the composite structures.These findings provide a theoretical basis for the structural design and safe operation of underground reservoir dams. 展开更多
关键词 Coal-concrete composite Acoustic emission Failure mode Strength analysis
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The Vulnerability Analysis of Some Typical Hash-Based RFID Authentication Protocols
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作者 Zhicai Shi Shitao Ren +1 位作者 fei wu Changzhi Wang 《Journal of Computer and Communications》 2016年第8期1-9,共9页
The low-cost RFID tags have very limited computing and storage resources and this makes it difficult to completely solve their security and privacy problems. Lightweight authentication is considered as one of the most... The low-cost RFID tags have very limited computing and storage resources and this makes it difficult to completely solve their security and privacy problems. Lightweight authentication is considered as one of the most effective methods to ensure the security in the RFID system. Many light-weight authentication protocols use Hash function and pseudorandom generator to ensure the anonymity and confidential communication of the RFID system. But these protocols do not provide such security as they claimed. By analyzing some typical Hash-based RFID authentication protocols, it is found that they are vulnerable to some common attacks. Many protocols cannot resist tracing attack and de-synchronization attack. Some protocols cannot provide forward security. Gy?z? Gódor and Sándor Imre proposed a Hash-based authentication protocol and they claimed their protocol could resist the well-known attacks. But by constructing some different attack scenarios, their protocol is shown to be vulnerable to tracing attack and de-synchronization attack. Based on the analysis for the Hash-based authentication protocols, some feasible suggestions are proposed to improve the security of the RFID authentication protocols. 展开更多
关键词 RFID Authentication Protocol VULNERABILITY Hash Function Security and Privacy
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基于生物炭的高级氧化技术降解水中有机污染物 被引量:9
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作者 吴飞 任伟 +3 位作者 程成 王艳 林恒 张晖 《化学进展》 SCIE CAS CSCD 北大核心 2022年第4期992-1010,共19页
碳基材料催化剂因具有良好的催化性能,同时可避免金属催化剂的重金属沥出造成的二次污染问题,常被应用于高级氧化领域。其中,以废弃生物质为原材料热解产生的生物炭,不仅具有催化潜力,还具有低成本和绿色环保等优势,被广泛用于活化过氧... 碳基材料催化剂因具有良好的催化性能,同时可避免金属催化剂的重金属沥出造成的二次污染问题,常被应用于高级氧化领域。其中,以废弃生物质为原材料热解产生的生物炭,不仅具有催化潜力,还具有低成本和绿色环保等优势,被广泛用于活化过氧化氢、过一硫酸氢盐和过二硫酸盐等过氧化物降解水中有机污染物。本文介绍了生物炭的前体种类和制备方法、阐述了二者对生物炭活化能力的影响,总结了生物炭活化过氧化物的机理,分析了水质对降解污染物的影响,综述了生物炭的改性、循环使用及再生,指出了这一技术存在的问题并对后续研究进行了展望。 展开更多
关键词 生物炭 高级氧化技术 过氧化物 自由基机理 非自由基机理
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SOCS1/JAK2/STAT3 axis regulates early brain injury induced by subarachnoid hemorrhage via inflammatory responses 被引量:22
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作者 Yang Wang Xiang-Qian Kong +6 位作者 fei wu Bin Xu De-Jun Bao Chuan-Dong Cheng Xiang-Ping Wei Yong-fei Dong Chao-Shi Niu 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第12期2453-2464,共12页
The SOCS1/JAK2/STAT3 axis is strongly associated with tumor growth and progression,and participates in cytokine secretion in many diseases.However,the effects of the SOCS1/JAK2/STAT3 axis in experimental subarachnoid ... The SOCS1/JAK2/STAT3 axis is strongly associated with tumor growth and progression,and participates in cytokine secretion in many diseases.However,the effects of the SOCS1/JAK2/STAT3 axis in experimental subarachnoid hemorrhage remain to be studied.A subarachnoid hemorrhage model was established in rats by infusing autologous blood into the optic chiasm pool.Some rats were first treated with JAK2/STAT3 small interfering RNA(Si-JAK2/Si-STAT3)or overexpression plasmids of JAK2/STAT3.In the brains of subarachnoid hemorrhage model rats,the expression levels of both JAK2 and STAT3 were upregulated and the expression of SOCS1 was downregulated,reaching a peak at 48 hours after injury.Simultaneously,the interactions between JAK2 and SOCS1 were reduced.In contrast,the interactions between JAK2 and STAT3 were markedly enhanced.Si-JAK2 and Si-STAT3 treatment alleviated cortical neuronal cell apoptosis and necrosis,destruction of the blood-brain barrier,brain edema,and cognitive functional impairment after subarachnoid hemorrhage.This was accompanied by decreased phosphorylation of JAK2 and STAT3 protein,decreased total levels of JAK2 and STAT3 protein,and increased SOCS1 protein expression.However,overexpression of JAK2 and STAT3 exerted opposite effects,aggravating subarachnoid hemorrhage-induced early brain injury.Si-JAK2 and Si-STAT3 inhibited M1-type microglial conversion and the release of pro-inflammatory factors(inducible nitric oxide synthase,interleukin-1β,and tumor necrosis factor-α)and increased the release of anti-inflammatory factors(arginase-1,interleukin-10,and interleukin-4).Furthermore,primary neurons stimulated with oxyhemoglobin were used to simulate subarachnoid hemorrhage in vitro,and the JAK2 inhibitor AG490 was used as an intervention.The in vitro results also suggested that neuronal protection is mediated by the inhibition of JAK2 and STAT3 expression.Together,our findings indicate that the SOCS1/JAK2/STAT3 axis contributes to early brain injury after subarachnoid hemorrhage both in vitro and in vivo by inducing inflammatory responses.This study was approved by the Animal Ethics Committee of Anhui Medical University and the First Affiliated Hospital of University of Science and Technology of China(approval No.LLSC-20180202)on March 1,2018. 展开更多
关键词 brain injury CYTOKINES in vitro model in vivo model inflammation MICROGLIA SOCS1/JAK2/STAT3 axis subarachnoid hemorrhage
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Local and global approaches of affinity propagation clustering for large scale data 被引量:15
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作者 Ding-yin XIA fei wu +1 位作者 Xu-qing ZHAN Yue-ting ZHUANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1373-1381,共9页
Recently a new clustering algorithm called 'affinity propagation' (AP) has been proposed, which efficiently clustered sparsely related data by passing messages between data points. However, we want to cluster ... Recently a new clustering algorithm called 'affinity propagation' (AP) has been proposed, which efficiently clustered sparsely related data by passing messages between data points. However, we want to cluster large scale data where the similarities are not sparse in many cases. This paper presents two variants of AP for grouping large scale data with a dense similarity matrix. The local approach is partition affinity propagation (PAP) and the global method is landmark affinity propagation (LAP). PAP passes messages in the subsets of data first and then merges them as the number of initial step of iterations; it can effectively reduce the number of iterations of clustering. LAP passes messages between the landmark data points first and then clusters non-landmark data points; it is a large global approximation method to speed up clustering. Experiments are conducted on many datasets, such as random data points, manifold subspaces, images of faces and Chinese calligraphy, and the results demonstrate that the two ap-proaches are feasible and practicable. 展开更多
关键词 CLUSTERING Affinity propagation Large scale data Partition affinity propagation Landmark affinity propagation
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