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Short-Term Synchronous and Asynchronous Ambient Noise Tomography in Urban Areas:Application to Karst Investigation 被引量:1
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作者 Ya Liu Jianghai Xia +3 位作者 Bo Guan Chaoqiang Xi Ling Ning Hao Zhang 《Engineering》 2025年第5期292-308,共17页
Dense-array ambient noise tomography is a powerful tool for achieving high-resolution subsurface imag-ing,significantly impacting geohazard prevention and control.Conventional dense-array studies,how-ever,require simu... Dense-array ambient noise tomography is a powerful tool for achieving high-resolution subsurface imag-ing,significantly impacting geohazard prevention and control.Conventional dense-array studies,how-ever,require simultaneous observations of numerous stations for extensive coverage.To conduct a comprehensive karst feature investigation with limited stations,we designed a new synchronous-asyn-chronous observation system that facilitates dense array observations.We conducted two rounds of asynchronous observations,each lasting approximately 24 h,in combination with synchronous backbone stations.We achieved wide-ranging coverage of the study area utilizing 197 nodal receivers,with an average station spacing of 7 m.The beamforming results revealed distinct variations in the noise source distributions between day and night.We estimated the source strength in the stationary phase zone and used a weighting scheme for stacking the cross-correlation functions(C ^(1) functions)to suppress the influ-ence of nonuniform noise source distributions.The weights were derived from the similarity coefficients between multicomponent C^(1)functions related to Rayleigh waves.We employed the cross-correlation of C ^(1) functions(C^(2)methods)to obtain the empirical Green’s functions between asynchronous stations.To eliminate artifacts in C ^(2) functions from higher-mode surface waves in C^(1)functions,we filtered the C^(1)functions on the basis of different particle motions linked to multimode Rayleigh waves.The dispersion measurements of Rayleigh waves obtained from both the C^(1)and C^(2)functions were utilized in surface wave tomography.The inverted three-dimensional(3D)shear-wave(S-wave)velocity model reveals two significant low-velocity zones at depths ranging from 40 to 60 m,which align well with the karst caves found in the drilling data.The method of short-term synchronous-asynchronous ambient noise tomography shows promise as a cost-effective and efficient approach for urban geohazard investigations. 展开更多
关键词 Seismic interferometry Surface wave tomography asynchronous ambient noise GEoHAZARDS Seismic ambient noise
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Blockchain and signcryption enabled asynchronous federated learning framework in fog computing
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作者 Zhou Zhou Youliang Tian +3 位作者 Jinbo Xiong Changgen Peng Jing Li Nan Yang 《Digital Communications and Networks》 2025年第2期442-454,共13页
Federated learning combines with fog computing to transform data sharing into model sharing,which solves the issues of data isolation and privacy disclosure in fog computing.However,existing studies focus on centraliz... Federated learning combines with fog computing to transform data sharing into model sharing,which solves the issues of data isolation and privacy disclosure in fog computing.However,existing studies focus on centralized single-layer aggregation federated learning architecture,which lack the consideration of cross-domain and asynchronous robustness of federated learning,and rarely integrate verification mechanisms from the perspective of incentives.To address the above challenges,we propose a Blockchain and Signcryption enabled Asynchronous Federated Learning(BSAFL)framework based on dual aggregation for cross-domain scenarios.In particular,we first design two types of signcryption schemes to secure the interaction and access control of collaborative learning between domains.Second,we construct a differential privacy approach that adaptively adjusts privacy budgets to ensure data privacy and local models'availability of intra-domain user.Furthermore,we propose an asynchronous aggregation solution that incorporates consensus verification and elastic participation using blockchain.Finally,security analysis demonstrates the security and privacy effectiveness of BSAFL,and the evaluation on real datasets further validates the high model accuracy and performance of BSAFL. 展开更多
关键词 Blockchain SIGNCRYPTIoN Federated learning asynchronous Fog computing
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Distributed asynchronous double accelerated optimization for ethylene plant considering delays
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作者 Ting Wang Zhongmei Li Wenli Du 《Chinese Journal of Chemical Engineering》 2025年第2期245-250,共6页
Considering the complexity of plant-wide optimization for large-scale industries, a distributed optimization framework to solve the profit optimization problem in ethylene whole process is proposed. To tackle the dela... Considering the complexity of plant-wide optimization for large-scale industries, a distributed optimization framework to solve the profit optimization problem in ethylene whole process is proposed. To tackle the delays arising from the residence time for materials passing through production units during the process with guaranteed constraint satisfaction, an asynchronous distributed parameter projection algorithm with gradient tracking method is introduced. Besides, the heavy ball momentum and Nesterov momentum are incorporated into the proposed algorithm in order to achieve double acceleration properties. The experimental results show that the proposed asynchronous algorithm can achieve a faster convergence compared with the synchronous algorithm. 展开更多
关键词 asynchronous distributed optimization Plant-wide optimization Heavy ball Nesterov Inequality constraints
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An Asynchronous Genetic Algorithm for Multi-agent Path Planning Inspired by Biomimicry
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作者 Bin Liu Shikai Jin +3 位作者 Yuzhu Li Zhuo Wang Donglai Zhao Wenjie Ge 《Journal of Bionic Engineering》 2025年第2期851-865,共15页
To address the shortcomings of traditional Genetic Algorithm (GA) in multi-agent path planning, such as prolonged planning time, slow convergence, and solution instability, this paper proposes an Asynchronous Genetic ... To address the shortcomings of traditional Genetic Algorithm (GA) in multi-agent path planning, such as prolonged planning time, slow convergence, and solution instability, this paper proposes an Asynchronous Genetic Algorithm (AGA) to solve multi-agent path planning problems effectively. To enhance the real-time performance and computational efficiency of Multi-Agent Systems (MAS) in path planning, the AGA incorporates an Equal-Size Clustering Algorithm (ESCA) based on the K-means clustering method. The ESCA divides the primary task evenly into a series of subtasks, thereby reducing the gene length in the subsequent GA process. The algorithm then employs GA to solve each subtask sequentially. To evaluate the effectiveness of the proposed method, a simulation program was designed to perform path planning for 100 trajectories, and the results were compared with those of State-Of-The-Art (SOTA) methods. The simulation results demonstrate that, although the solutions provided by AGA are suboptimal, it exhibits significant advantages in terms of execution speed and solution stability compared to other algorithms. 展开更多
关键词 Multi-agent path planning asynchronous genetic algorithm Equal-size clustering Genetic algorithm
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3D trajectory reconstruction of moving points based on asynchronous cameras
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作者 Huayu Huang Yang Shang +1 位作者 Banglei Guan Qifeng Yu 《Acta Mechanica Sinica》 2025年第7期197-210,共14页
Photomechanics is a crucial branch of solid mechanics.The localization of point targets constitutes a fundamental problem in optical experimental mechanics,with extensive applications in various missions of unmanned a... Photomechanics is a crucial branch of solid mechanics.The localization of point targets constitutes a fundamental problem in optical experimental mechanics,with extensive applications in various missions of unmanned aerial vehicles.Localizing moving targets is crucial for analyzing their motion characteristics and dynamic properties.Reconstructing the trajectories of points from asynchronous cameras is a significant challenge.It encompasses two coupled sub-problems:Trajectory reconstruction and camera synchronization.Present methods typically address only one of these sub-problems individually.This paper proposes a 3D trajectory reconstruction method for point targets based on asynchronous cameras,simultaneously solving both sub-problems.Firstly,we extend the trajectory intersection method to asynchronous cameras to resolve the limitation of traditional triangulation that requires camera synchronization.Secondly,we develop models for camera temporal information and target motion,based on imaging mechanisms and target dynamics characteristics.The parameters are optimized simultaneously to achieve trajectory reconstruction without accurate time parameters.Thirdly,we optimize the camera rotations alongside the camera time information and target motion parameters,using tighter and more continuous constraints on moving points.The reconstruction accuracy is significantly improved,especially when the camera rotations are inaccurate.Finally,the simulated and real-world experimental results demonstrate the feasibility and accuracy of the proposed method.The real-world results indicate that the proposed algorithm achieved a localization error of 112.95 m at an observation distance range of 15-20 km. 展开更多
关键词 PHoToMECHANICS 3D trajectory reconstruction asynchronous cameras Temporal polynomials Bundle adjustment
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Adaptive Waiting Time Asynchronous Federated Learning in Edge Computing
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作者 Cui Taiping Liu Wenhao +2 位作者 Shen Bin Huang Xiaoge Chen Qianbin 《China Communications》 2025年第9期368-385,共18页
Federated learning combined with edge computing has greatly facilitated transportation in real-time applications such as intelligent traffic sys-tems.However,synchronous federated learning is in-efficient in terms of ... Federated learning combined with edge computing has greatly facilitated transportation in real-time applications such as intelligent traffic sys-tems.However,synchronous federated learning is in-efficient in terms of time and convergence speed,mak-ing it unsuitable for high real-time requirements.To address these issues,this paper proposes an Adap-tive Waiting time Asynchronous Federated Learn-ing(AWTAFL)based on Dueling Double Deep Q-Network(D3QN).The server dynamically adjusts the waiting time using the D3QN algorithm based on the current task progress and energy consumption,aim-ing to accelerate convergence and save energy.Addi-tionally,this paper presents a new federated learning global aggregation scheme,where the central server performs weighted aggregation based on the freshness and contribution of client parameters.Experimen-tal simulations demonstrate that the proposed algo-rithm significantly reduces the convergence time while ensuring model quality and effectively reducing en-ergy consumption in asynchronous federated learning.Furthermore,the improved global aggregation update method enhances training stability and reduces oscil-lations in the global model convergence. 展开更多
关键词 adaptive waiting time asynchronous federated learning D3QN edge computing
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Asynchronously fault detection for flight vehicles with unstable modes via MDLF and MDADT method
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作者 Sheng Luo Xin Liu +2 位作者 Yanfei Cheng Shiyu Shuai Haoyu Cheng 《Defence Technology(防务技术)》 2025年第7期417-436,共20页
This research focuses on detecting faults in flight vehicles with unstable subsystems operating asynchronously.By accounting for asynchronous switching,a switched model is established,and filters for fault detection(F... This research focuses on detecting faults in flight vehicles with unstable subsystems operating asynchronously.By accounting for asynchronous switching,a switched model is established,and filters for fault detection(FD)in unstable subsystems are developed.The FD challenge is then transformed into an H∞filtering issue.Utilizing the multiple discontinuous Lyapunov function(MDLF)approach and the mode-dependent average dwell time(MDADT)method,sufficient conditions are derived to ensure stability during both fast and slow switching.Furthermore,the existence and solutions for FD filters are provided through linear matrix inequalities(LMIs).The simulation outcomes demonstrated the excellent performance of the developed method in studied cases. 展开更多
关键词 Fault detection asynchronous switching H∞filtering Multiple discontinuous lyapunov function Mode-dependent average dwell time Linear matrix inequalities(LMIs)
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An Asynchronous Implementation of Add-Compare-Select Processor for Communication Systems
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作者 赵冰 仇玉林 +1 位作者 吕铁良 黑勇 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第5期886-892,共7页
A novel asynchronous ACS(add-compare-select) processor for Viterbi decoder is described.It is controlled by local handshake signals instead of the globe clock.The circuits of asynchronous adder unit,asynchronous compa... A novel asynchronous ACS(add-compare-select) processor for Viterbi decoder is described.It is controlled by local handshake signals instead of the globe clock.The circuits of asynchronous adder unit,asynchronous comparator unit,and asynchronous selector unit are proposed.A full-custom design of asynchronous 4-bit ACS processor is fabricated in CSMC-HJ 0.6μm CMOS 2P2M mixed-mode process.At a supply voltage of 5V,when it operates at 20MHz,the power consumption is 75.5mW.The processor has no dynamic power consumption when it awaits an opportunity in sleep mode.The results of performance test of asynchronous 4-bit ACS processor show that the average case response time 19.18ns is only 82% of the worst-case response time 23.37ns.Compared with the synchronous 4-bit ACS processor in power consumption and performance by simulation,it reveals that the asynchronous ACS processor has some advantages than the synchronous one. 展开更多
关键词 asynchronous circuits Viterbi decoder ACS response time
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有机肥和生物菌剂对菜地土壤N_(2)O排放及土壤团聚体的影响
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作者 马静 陆昕昱 +1 位作者 宋俊杰 孙丽英 《农业环境科学学报》 北大核心 2026年第1期251-261,共11页
为探究不同施肥处理对菜地土壤N_(2)O排放、产量及土壤团聚体的影响,本研究以南京地区菜地为研究对象,设置不施氮肥(CK)、施化学氮肥(U)、化学氮肥和生物菌剂配施(UM)、有机肥替代25%化学氮肥(O)、有机肥替代25%化学氮肥和生物菌剂配施(... 为探究不同施肥处理对菜地土壤N_(2)O排放、产量及土壤团聚体的影响,本研究以南京地区菜地为研究对象,设置不施氮肥(CK)、施化学氮肥(U)、化学氮肥和生物菌剂配施(UM)、有机肥替代25%化学氮肥(O)、有机肥替代25%化学氮肥和生物菌剂配施(OM)5个处理。采用静态暗箱-气相色谱法,观测菜地土壤N_(2)O的排放,并分析不同施肥处理对菜地土壤N_(2)O排放量、综合温室效应(GWP)、温室气体排放强度(GHGI)、产量、土壤团聚体组成、经济效益等的影响。结果表明:与U处理相比,O处理土壤N_(2)O累积排放量增长了12.70%,UM和OM处理土壤N_(2)O累积排放量均有所降低,其中,UM处理降低了16.67%,OM处理显著降低了23.81%(P<0.05)。在各施肥处理中,OM处理产量最高,为11.9 t·hm^(-2),O处理次之,为11.2 t·hm^(-2)。此外,O和OM处理降低了<0.25 mm团聚体占比,提高了土壤中大团聚体占比,增加了土壤团聚体稳定性。研究表明,有机肥配施生物菌剂处理可以减缓菜地土壤N_(2)O排放并提高作物产量和经济效益,是实现农业低碳高产的一种可行性措施。 展开更多
关键词 有机肥 生物菌剂 N_(2)o 团聚体 产量
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活性炭负载纳米铁材料对人工湿地脱氮和N_(2)O排放的影响
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作者 郝桂珍 范慧双 +2 位作者 张南南 李振河 徐利 《环境工程技术学报》 北大核心 2026年第1期148-157,共10页
人工湿地是污水处理厂尾水深度处理的有效手段,但尾水中碳氮比(C/N)较低且化学需氧量(COD)难以被利用,导致传统人工湿地处理该类尾水时存在硝化、反硝化反应不完全的问题,且有大量N_(2)O气体(温室气体)产生并逸出至大气,生态效益欠佳。... 人工湿地是污水处理厂尾水深度处理的有效手段,但尾水中碳氮比(C/N)较低且化学需氧量(COD)难以被利用,导致传统人工湿地处理该类尾水时存在硝化、反硝化反应不完全的问题,且有大量N_(2)O气体(温室气体)产生并逸出至大气,生态效益欠佳。针对该问题,制备了活性炭负载纳米铁材料Fe-AC,设计构建了三组人工湿地(CW1、CW2、CW3),分别填加纯砾石(空白对照)、砾石+3%Fe-AC、砾石+8%Fe-AC,模拟污水处理厂尾水的低C/N水质,利用铁与碳两极间的电位差形成的微电解原理强化人工湿地的脱氮过程,探究不同Fe-AC投加比例对人工湿地脱氮和N_(2)O减排的影响,并分析其影响机制。结果表明:Fe-AC在人工湿地中可自发形成原电池释放电子和[H],作为电子供体促进氮的转化和提高微生物的活性。在人工湿地模拟进水COD 28 mg/L、TN 18 mg/L,即C/N=1.5的条件下,CW1、CW2、CW3的出水COD分别稳定在6.0、4.5、4.0 mg/L,去除率达到72%、83%、85%;总氮(TN)浓度分别稳定在14.0、0.5、0.4 mg/L,去除率达到22%、97%、97%,加入Fe-AC的人工湿地对COD和TN的去除效果显著;CW1、CW2和CW3的N_(2)O排放量分别为1 330.87、629.86、576.49μg/(m^(2)·h),与空白对照组(CW1)相比,CW2和CW3对N_(2)O的减排率分别达到52.72%和56.52%,加入Fe-AC对人工湿地N_(2)O的减排效果明显;加入Fe-AC的CW2和CW3内部拟杆菌门和甲基营养型菌属的丰度明显提高,其他与反硝化和有机物降解有关的功能菌也得到筛选和优化。综合三组人工湿地的运行效果,CW2中加入3%的Fe-AC即可满足对人工湿地脱氮效果的提升和N_(2)O气体的减排,比CW3中8%的Fe-AC更加经济合理。 展开更多
关键词 人工湿地 铁碳微电解 低碳氮比 N_(2)o 反硝化
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废弃煤矿巷道CO_(2)“封存-利用”技术探索及转化效率研究
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作者 来兴平 雷彤 +3 位作者 张楠 胡添龙 介凯 刘旭超 《西安科技大学学报》 北大核心 2026年第1期15-26,共12页
为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧... 为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧化物电解池(SOEC)技术构建巷道反应硐室与实验室微型反应腔之间尺度映射关系,形成室内试验-井下应用的参数对应体系;通过开展恒电流共电解试验以及气相色谱对气体成分分析,系统揭示反应温度与CO_(2)/H_(2)O气体比例对CO_(2)转化效率的影响。结果表明:在保持A/V不变的条件下,巷道反应硐室尺寸为2.4 m×6 m×3.6 m,对应有效反应面积为384 m^(2);法拉第效率随着温度的升高呈现出“先下降后升高”的特征,随着CO_(2)/H_(2)O气体比例的增加而降低,CO_(2)转化率随着温度升高而显著提升,随着CO_(2)/H_(2)O气体比例增加而降低,在温度为850℃、气体比例CO_(2)∶H_(2)O=1∶1的共电解条件下,CO_(2)实现最优转化效率,转化率达72.22%,法拉第效率为61.77%。研究为实现废弃煤矿巷道CO_(2)封存与高值化利用提供了理论依据与技术支撑。 展开更多
关键词 废弃煤矿 固体氧化物电解池 Co_(2)/H_(2)o共电解 法拉第效率 Co_(2)转化率 相似理论
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基于GC-O-MS的酸凝、酶凝奶酪挥发性风味比较及氨基酸含量分析
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作者 徐颖 王欢 +1 位作者 荣良燕 李儒仁 《中国乳品工业》 北大核心 2026年第2期36-43,共8页
为探讨中西方奶酪风味差异,文章采用感官评价结合气相色谱-嗅闻-质谱(Gas chromatography-olfactometry-mass spectrometry,GC-O-MS)技术,检测并比较了4种奶酪样品(SNL、CNL、WTB、ZNL)的挥发性风味物质及游离氨基酸含量。结果表明,共... 为探讨中西方奶酪风味差异,文章采用感官评价结合气相色谱-嗅闻-质谱(Gas chromatography-olfactometry-mass spectrometry,GC-O-MS)技术,检测并比较了4种奶酪样品(SNL、CNL、WTB、ZNL)的挥发性风味物质及游离氨基酸含量。结果表明,共检测到47种挥发性化合物,其中SNL和CNL分别含有24种和25种,WTB和ZNL分别含有16种和11种。SNL氨基酸含量最高,其次为CNL、WTB和ZNL。分析表明,ZNL具有显著的奶香、果香和烤面包香气,且酸属性得分较低,使其在整体香气平衡与协调上表现优异,喜好度评分最高。文章通过系统分析不同奶酪的挥发性化合物及氨基酸成分,为中西方奶酪的风味特征提供了数据支持,也为未来的产品开发和市场定位提供参考。 展开更多
关键词 奶酪 感官评价 气相色谱-嗅闻-质谱技术 挥发性风味物质
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利拉鲁肽通过上调叉头框转录因子O3改善肾小管间质损伤机制的研究
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作者 康惠敏 方昕 《中国糖尿病杂志》 北大核心 2026年第1期52-57,共6页
目的探讨利拉鲁肽(Lir)通过上调叉头框转录因子O3(FoxO3)改善肾小管间质损伤的机制。方法将24只C57BL/6小鼠分为正常对照(NC)、DM及Lir干预(Lir)组,每组8只。Masson及过碘酸希夫染色检测肾小管间质纤维化及肾小管损伤情况,免疫组织化学... 目的探讨利拉鲁肽(Lir)通过上调叉头框转录因子O3(FoxO3)改善肾小管间质损伤的机制。方法将24只C57BL/6小鼠分为正常对照(NC)、DM及Lir干预(Lir)组,每组8只。Masson及过碘酸希夫染色检测肾小管间质纤维化及肾小管损伤情况,免疫组织化学染色和Western blot检测肾脏中肾小管上皮细胞凋亡及FoxO3蛋白表达,试剂盒检测血肌酐(Scr)、BUN、胱抑素C(CysC)和中性粒细胞明胶酶相关脂质运载蛋白(NGAL)水平。结果DM组Scr、BUN、CysC、NGAL、蓝色胶原纤维面积百分比、肾小管损伤指数、活化的胱天蛋白酶3蛋白表达高于NC、Lir组(P<0.05),FoxO3阳性面积百分比低于NC、Lir组(P<0.05)。结论Lir可有效改善DM肾损伤,其潜在机制可能是通过上调FoxO3表达,减少肾小管上皮细胞凋亡,改善肾小管损伤,进而改善肾小管间质纤维化进展。 展开更多
关键词 胰高血糖素样肽-1受体激动剂 利拉鲁肽 叉头框转录因子o3 肾小管间质损伤
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利用废弃电蚊香片制备Fe_(x)O_(y)/C复合微波吸收材料
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作者 力国民 李泽宇 +1 位作者 高洁 梁丽萍 《聊城大学学报(自然科学版)》 2026年第2期263-273,共11页
生物质碳因其环境友好、成本低廉和导电性良好等优点,成为研究热点。以废弃电蚊香片为主要原料,通过高温焙烧和引入磁性组分(Fe_(x)O_(y)),制备了Fe_(x)O_(y)/C复合吸波材料。研究发现,负载Fe_(x)O_(y)后,Fe_(x)O_(y)/C复合材料的吸波... 生物质碳因其环境友好、成本低廉和导电性良好等优点,成为研究热点。以废弃电蚊香片为主要原料,通过高温焙烧和引入磁性组分(Fe_(x)O_(y)),制备了Fe_(x)O_(y)/C复合吸波材料。研究发现,负载Fe_(x)O_(y)后,Fe_(x)O_(y)/C复合材料的吸波性能显著提升。其中,FVM-0.6-600在1.5 mm涂层厚度下的最小反射损耗(RLmin)值达到-19.2 dB,有效吸收带宽(EAB)为5.3 GHz;FVM-0.6-800在2 mm涂层厚度下的RLmin值为-25.6 dB,EAB为4.5 GHz。该研究实现了废弃电蚊香片的高值化和资源化利用,具有广阔的应用前景。 展开更多
关键词 废弃电蚊香片 Fe3o4/Fe/C复合材料 微波吸收
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血清FOXO1和PPAR-γ水平在下肢深静脉血栓诊断中的应用价值
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作者 王征 张丽沙 +3 位作者 贾晓敏 郑丽环 焦清海 郭志坤 《蚌埠医科大学学报》 2026年第1期67-70,共4页
目的:探讨血清叉头转录因子O1(FOXO1)和过氧化物酶体增殖物激活受体-γ(PPAR-γ)水平在下肢深静脉血栓(DVT)诊断中的应用价值。方法:选取下肢障碍病人132例,按照数字减影血管造影(DSA)诊断结果,将病人分为DVT组87例和非DVT组45例,另选... 目的:探讨血清叉头转录因子O1(FOXO1)和过氧化物酶体增殖物激活受体-γ(PPAR-γ)水平在下肢深静脉血栓(DVT)诊断中的应用价值。方法:选取下肢障碍病人132例,按照数字减影血管造影(DSA)诊断结果,将病人分为DVT组87例和非DVT组45例,另选取同期体检健康者132名作为对照组。分析DVT发生的影响因素及DVT病人血清FOXO1和PPAR-γ表达水平的相关性,并采用ROC曲线分析血清FOXO1和PPAR-γ水平对DVT的诊断价值。结果:3组凝血酶原时间、活化部分凝血酶原时间、血小板计数和FOXO1、PPAR-γ表达水平间差异均有统计学意义(P<0.01)。DVT病人血清FOXO1和PPAR-γ表达水平呈负相关关系(P<0.05)。高血压史、凝血酶原时间<8 s、活化部分凝血酶原时间<27 s、血小板计数≥300×10^(9)/L和高FOXO1均为DVT的独立危险因素,而PPAR-γ为其保护因素(P<0.05~P<0.01)。血清FOXO1、PPAR-γ以及二者联合检测诊断DVT的AUC分别为0.745、0.657、0.831,二者联合检测优于单独检测(P<0.01)。结论:血清FOXO1、PPAR-γ表达水平与DVT发生密切相关,二者联合检测对DVT具有较好诊断价值,可用于辅助诊断DVT。 展开更多
关键词 下肢深静脉血栓 叉头转录因子o1 过氧化物酶体增殖物激活受体-Γ
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犬猫尿源性大肠埃希菌的耐药性及O抗原多价血清型分析
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作者 陈琳 张俊丰 +2 位作者 区卓麟 于淼淼 杨雨秋 《上海畜牧兽医通讯》 2026年第1期99-103,共5页
为分析犬猫尿源性大肠埃希菌的耐药特征及O抗原多价血清型,无菌采集犬猫尿液样品,分离、纯化并鉴定大肠埃希菌,用纸片扩散法检测分离菌对四环素、庆大霉素、复方新诺明、头孢曲松、恩诺沙星、阿莫西林-克拉维酸、阿莫西林、多西环素8种... 为分析犬猫尿源性大肠埃希菌的耐药特征及O抗原多价血清型,无菌采集犬猫尿液样品,分离、纯化并鉴定大肠埃希菌,用纸片扩散法检测分离菌对四环素、庆大霉素、复方新诺明、头孢曲松、恩诺沙星、阿莫西林-克拉维酸、阿莫西林、多西环素8种药物的敏感性,并通过玻片凝集法检测其与21种O抗原多价诊断血清的凝集反应。结果显示:共分离鉴定到48株大肠埃希菌,其中32株为多重耐药菌;分离菌株对阿莫西林的耐药率(77.08%)最高,对头孢曲松、阿莫西林-克拉维酸及庆大霉素的耐药率相对较低;36株大肠埃希菌可与1~5种多价血清发生凝集反应,其余12株未与任何受试血清发生凝集反应。研究表明,48株犬猫尿源性大肠埃希菌对常用抗菌药物的耐药性强,表现出多重耐药性,且血清型多样,研究结果可为临床合理用药及进一步开展流行病学研究提供参考。 展开更多
关键词 尿源性大肠埃希菌 耐药性 抗菌药物敏感性测试 o抗原 多价血清
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叉头框转录因子O3影响骨代谢及参与多类骨相关疾病的病理进程
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作者 韩杰 胡天发 +2 位作者 吴亚超 农彬 玉开龙 《中国组织工程研究》 北大核心 2026年第22期5770-5781,共12页
背景:骨代谢紊乱会引起骨相关疾病的发生,而叉头框转录因子O3可以通过调节氧化应激、自噬水平等来影响骨组织细胞增殖、分化与凋亡,调控骨代谢过程。目的:系统性分析叉头框转录因子O3调控骨代谢及其在骨科疾病中作用机制的相关研究文献... 背景:骨代谢紊乱会引起骨相关疾病的发生,而叉头框转录因子O3可以通过调节氧化应激、自噬水平等来影响骨组织细胞增殖、分化与凋亡,调控骨代谢过程。目的:系统性分析叉头框转录因子O3调控骨代谢及其在骨科疾病中作用机制的相关研究文献,为后续以叉头框转录因子O3为靶点治疗骨疾病的研究提供参考。方法:以“(SU=FoxO3a OR SU=Foxo3 OR SU=Forkhead box O3 OR SU=叉头框转录因子O3)AND SU=骨”为检索句在中国知网进行检索,以“主题:(“FoxO3a”)OR主题:(“Foxo3”)OR主题:(“Forkhead box O3”)OR主题:(“叉头框转录因子O3”)AND主题:(“骨”)”为检索句在万方医学数据库进行检索;以“((FoxO3a)OR(Foxo3)OR(Forkhead box O3))AND((bone)OR(Skeleton))”为检索句在PubMed数据库进行检索,排除陈旧、重复、质量较差以及不相关的文献,最终纳入56篇文献进行综述分析。结果与结论:①叉头框转录因子O3与骨髓间充质干细胞:叉头框转录因子O3能够促进成骨谱系的形成,还可通过激活自噬促进早期成骨分化。同时,叉头框转录因子O3在骨髓间充质干细胞中体现抗氧化特性,保护细胞免受氧化应激诱导的衰老。②叉头框转录因子O3与成骨细胞:叉头框转录因子O3在成骨细胞中能通过干扰Wnt/β-连环蛋白通路抑制成骨,同时能激活抗氧化酶保护成熟成骨细胞。叉头框转录因子O3能促进成骨祖细胞的增殖,并通过激活自噬促进成骨分化。③叉头框转录因子O3与破骨细胞:叉头框转录因子O3表达可抵抗氧化应激和激活自噬抑制破骨细胞生成。④叉头框转录因子O3与骨细胞:叉头框转录因子O3可通过抗氧化作用保护骨细胞,还可通过抑制p16和p53信号通路和抑制衰老相关分泌表型来减少骨流失。⑤叉头框转录因子O3与软骨细胞:叉头框转录因子O3在骨关节炎中对软骨细胞起到保护作用,抑制软骨细胞分解或凋亡,促进软骨细胞外基质合成,可抑制软骨细胞肥大;然而,叉头框转录因子O3与Runt相关转录因子1在软骨细胞中高度共表达却会促进软骨祖细胞的早期软骨形成和终末肥大。⑥叉头框转录因子O3通过参与氧化应激抵抗与调控自噬等过程影响骨代谢,参与多类骨相关疾病的病理进程。 展开更多
关键词 叉头框转录因子o3(Foxo3a) 骨代谢 病理机制 成骨细胞 破骨细胞 软骨细胞 信号通路 综述
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Stability of Iterative Learning Control with Data Dropouts via Asynchronous Dynamical System 被引量:15
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作者 Xu-Hui Bu Zhong-Sheng Hou 《International Journal of Automation and computing》 EI 2011年第1期29-36,共8页
In this paper, the stability of iterative learning control with data dropouts is discussed. By the super vector formulation, an iterative learning control (ILC) system with data dropouts can be modeled as an asynchr... In this paper, the stability of iterative learning control with data dropouts is discussed. By the super vector formulation, an iterative learning control (ILC) system with data dropouts can be modeled as an asynchronous dynamical system with rate constraints on events in the iteration domain. The stability condition is provided in the form of linear matrix inequalities (LMIS) depending on the stability of asynchronous dynamical systems. The analysis is supported by simulations. 展开更多
关键词 Iterative learning control (ILC) networked control systems (NCSs) data dropouts asynchronous dynamical system robustness.
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Dynamic Coupled Analysis of the Floating Platform Using the Asynchronous Coupling Algorithm 被引量:5
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作者 Shan Ma Wenyang Duan 《Journal of Marine Science and Application》 2014年第1期85-91,共7页
This paper discusses the numerical modeling of the dynamic coupled analysis of the floating platform and mooring/risers using the asynchronous coupling algorithm with the purpose to improve the computational efficienc... This paper discusses the numerical modeling of the dynamic coupled analysis of the floating platform and mooring/risers using the asynchronous coupling algorithm with the purpose to improve the computational efficiency when multiple lines are connected to the platform. The numerical model of the platform motion simulation in wave is presented. Additionally, how the asynchronous coupling algorithm is implemented during the dynamic coupling analysis is introduced. Through a comparison of the numerical results of our developed model with commercial software for a SPAR platform, the developed numerical model is checked and validated. 展开更多
关键词 floating PLATFoRM PLATFoRM MoTIoNS DYNAMIC coupledanalysis asynchronous coupling algorithm MooRING line TENSIoNS SPAR PLATFoRM
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