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大梯度形变矿区InSAR三维形变的参考相位修复和PIM融合监测方法 被引量:1
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作者 李全生 戴华阳 +1 位作者 王志红 王菲 《采矿与安全工程学报》 北大核心 2025年第3期660-672,共13页
InSAR技术应用于地表沉陷监测主要面临两个技术问题:其一,雷达视线方向(LOS)形变是一维形变,需借助地表移动规律性模型解算地表三维形变,存在参考模型选择合理性和融合解算问题;其二,矿区大梯度形变通常超出了InSAR技术的监测能力,导致... InSAR技术应用于地表沉陷监测主要面临两个技术问题:其一,雷达视线方向(LOS)形变是一维形变,需借助地表移动规律性模型解算地表三维形变,存在参考模型选择合理性和融合解算问题;其二,矿区大梯度形变通常超出了InSAR技术的监测能力,导致大梯度形变区出现整周相位缺失的失相干现象。针对以上问题,提出了一种基于参考相位修复法和单轨InSAR形变计算模型的大梯度形变矿区地表三维形变计算方法,具体步骤如下:基于地表移动概率积分模型(PIM)获取形变区参考相位,通过InSAR观测干涉相位与参考相位求差得到剩余缠绕相位,解缠后叠加参考相位实现形变相位的修复;基于PIM模型推导地表移动矢量俯角和方位角公式,结合LOS向形变解算地表三维形变。针对形变量达数米的剧烈大量级形变区域,其更大的形变梯度可能超出参考相位修复法的适用范围,提出了一种基于PIM融合法的大量级形变计算方法。以上湾煤矿采厚8.8 m高强度开采的12401工作面为研究对象,Sentinel-1A为数据源,采用上述方法进行地表大梯度形变InSAR监测研究。研究结果表明:Sentinel-1A InSAR干涉图解缠的最大相位为-6.7 rad,修复后相位最大值为-337.37 rad,成功修复了大梯度形变区域的形变相位;通过解算,研究区地表三维移动盆地最大下沉值为1551 mm,最大水平移动值为754 mm,下沉值精度RMSE为53 mm,水平移动值精度RMSE为37 mm,实现了矿区大梯度、大量级地表三维形变的精细化监测;基于PIM融合法计算大梯度形变矿区地表三维形变,最大下沉值和水平移动值分别为6101和2541 mm,下沉值精度RMSE为153 mm,水平移动值精度RMSE为67 mm。 展开更多
关键词 INSAR 参考相位修复法 三维形变计算 pim模型
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PBI基/PIM-1复合离聚物提高碱性膜氢燃料电池性能
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作者 王蕾蕾 吴雪梅 +3 位作者 陈婉婷 逄博 崔福军 贺高红 《膜科学与技术》 北大核心 2025年第5期133-142,共10页
本研究提出一种用于碱性阴离子交换膜燃料电池(AEMFC)催化层的新型复合离聚物设计。该设计将高离子传导性的亲水聚合物(UTA-PBI-25%)与具有微孔结构的疏水聚合物(PIM-1)相结合。亲水组分提供优异的离子传导性和催化剂结合能力,而疏水微... 本研究提出一种用于碱性阴离子交换膜燃料电池(AEMFC)催化层的新型复合离聚物设计。该设计将高离子传导性的亲水聚合物(UTA-PBI-25%)与具有微孔结构的疏水聚合物(PIM-1)相结合。亲水组分提供优异的离子传导性和催化剂结合能力,而疏水微孔组分则有效抑制溶胀并显著增强催化层的透气性。优化配比后的复合离聚物实现了催化层结构的协同改善,使其在催化剂分散、电化学性能和电极反应效率方面表现优异。应用于氢氧燃料电池时,该复合离聚物显著提升了电池在高电流密度下的输出性能,获得了高水平的峰值功率密度。这种“亲水黏结剂-疏水造孔剂”复合策略有效兼顾了催化层对离子传导性和气体传质能力的需求,为优化AEMFC性能提供了新思路。 展开更多
关键词 离聚物 聚苯并咪唑 自聚微孔聚合物(pims) 催化层三相界面 燃料电池
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神经节苷脂调控PIM-1/PI3K/Akt信号通路介导的细胞焦亡改善新生大鼠缺血缺氧脑损伤的机制
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作者 徐琳琳 王艺 +1 位作者 李峰 赵曼 《中国药理学通报》 北大核心 2025年第8期1517-1523,共7页
目的探讨神经节苷脂(ganglioside,GM1)对新生大鼠缺血缺氧脑损伤(hypoxic-ischemic brain injury,HIBI)的保护作用及机制。方法将80只7 d龄SD新生大鼠随机分为4组:假手术组(Sham)、HIBI组、GM1组及GM1+PIM-1抑制剂组(GM1+PIM-1 inhibito... 目的探讨神经节苷脂(ganglioside,GM1)对新生大鼠缺血缺氧脑损伤(hypoxic-ischemic brain injury,HIBI)的保护作用及机制。方法将80只7 d龄SD新生大鼠随机分为4组:假手术组(Sham)、HIBI组、GM1组及GM1+PIM-1抑制剂组(GM1+PIM-1 inhibitor),每组各20只。除Sham组外,其余3组新生大鼠均采用左侧颈部总动脉结扎及缺氧处理构建新生大鼠HIBI模型。Sham组新生大鼠仅做颈部切口,不做缺血缺氧处理。HIBI模型构建成功后,GM1组新生大鼠腹腔注射GM1(20 mg·kg^(-1)·d^(-1)),连续给药3 d,GM1+PIM-1 inhibitor组新生大鼠侧脑室一次性注射PIM-1 inhibitor(5 mg·kg^(-1))后腹腔注射GM1(20 mg·kg^(-1)·d^(-1)),连续给药3 d,Sham和HIBI组新生大鼠腹腔注射等量生理盐水。采用Longa法评估神经功能损伤情况;TTC染色检测脑梗死体积比率;HE染色观察海马组织病理学情况;TUNEL染色检测海马神经元凋亡情况;ELISA检测海马组织IL-1β和IL-18水平;Western blot检测海马组织PIM-1/PI3K/Akt信号通路蛋白及焦亡相关蛋白(NLRP3、ASC、caspase-1 p20、GSDMD-N)表达。结果与Sham组相比,HIBI组新生大鼠Longa评分、脑梗死体积、海马神经元凋亡率、IL-1β,IL-18水平、焦亡相关蛋白表达均明显升高(P<0.05)PIM-1蛋白表达、p-PI3K/PI3K、p-Akt/Akt比值均明显降低(P<0.05)。与HIBI组相比,GM1组新生大鼠Longa评分、脑梗死体积、海马神经元凋亡率、IL-1β,IL-18水平、焦亡相关蛋白表达均明显降低(P<0.05),PIM-1蛋白表达、p-PI3K/PI3K、p-Akt/Akt比值均明显升高(P<0.05)。与GM1组相比,GM1+PIM-1 inhibitor组新生大鼠Longa评分、脑梗死体积、海马神经元凋亡率、IL-1β,IL-18水平、焦亡相关蛋白表达均明显升高(P<0.05),PIM-1蛋白表达、p-PI3K/PI3K、p-Akt/Akt比值均明显降低(P<0.05)。结论GM1能够改善新生大鼠HIBI,机制与激活PIM-1/PI3K/Akt信号通路,抑制海马神经元焦亡相关。 展开更多
关键词 神经节苷脂 缺血缺氧脑损伤 pim-1/PI3K/Akt信号通路 细胞焦亡 NLRP3/ASC/caspase-1
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A Multi-Level Semantic Constraint Approach for Highway Tunnel Scene Twin Modeling 被引量:1
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作者 LI Yufei XIE Yakun +3 位作者 CHEN Mingzhen ZHAO Yaoji TU Jiaxing HU Ya 《Journal of Geodesy and Geoinformation Science》 2025年第2期37-56,共20页
As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods ge... As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods generally have problems such as insufficient 3D scene description capability and low dynamic update efficiency,which are difficult to meet the demand of real-time accurate management.For this reason,this paper proposes a vehicle twin modeling method for road tunnels.This approach starts from the actual management needs,and supports multi-level dynamic modeling from vehicle type,size to color by constructing a vehicle model library that can be flexibly invoked;at the same time,semantic constraint rules with geometric layout,behavioral attributes,and spatial relationships are designed to ensure that the virtual model matches with the real model with a high degree of similarity;ultimately,the prototype system is constructed and the case region is selected for the case study,and the dynamic vehicle status in the tunnel is realized by integrating real-time monitoring data with semantic constraints for precise virtual-real mapping.Finally,the prototype system is constructed and case experiments are conducted in selected case areas,which are combined with real-time monitoring data to realize dynamic updating and three-dimensional visualization of vehicle states in tunnels.The experiments show that the proposed method can run smoothly with an average rendering efficiency of 17.70 ms while guaranteeing the modeling accuracy(composite similarity of 0.867),which significantly improves the real-time and intuitive tunnel management.The research results provide reliable technical support for intelligent operation and emergency response of road tunnels,and offer new ideas for digital twin modeling of complex scenes. 展开更多
关键词 highway tunnel twin modeling multi-level semantic constraints tunnel vehicles multidimensional modeling
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Solubility and Thermodynamic Modeling of 3⁃Nitro⁃1,2,4⁃triazole⁃5⁃one(NTO)in Different Binary Solvents 被引量:1
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作者 GUO Hao-qi YANG Yu-lin 《含能材料》 北大核心 2025年第3期295-303,共9页
Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging f... Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging from 278.15 K to 318.15 K.The solubility in each system was found to be positively correlated with temperature.Furthermore,solubility data were analyzed using four equations:the modified Apelblat equation,Van’t Hoff equation,λh equation and CNIBS/R-K equations,and they provided satisfactory results for both two systems.The average root-mean-square deviation(105RMSD)values for these models were less than 13.93.Calculations utilizing the Van’t Hoff equation and Gibbs equations facilitated the derivation of apparent thermodynamic properties of NTO dissolution in the two systems,including values for Gibbs free energy,enthalpy and entropy.The%ζ_(H)is larger than%ζ_(TS),and all the%ζ_(H)data are≥58.63%,indicating that the enthalpy make a greater contribution than entropy to theΔG_(soln)^(Θ). 展开更多
关键词 3-nitro-l 2 4-triazole-5-one(NTO) SOLUBILITY thermodynamic models apparent thermodynamic analysis
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Candida albicans and colorectal cancer:A paradoxical role revealed through metabolite profiling and prognostic modeling 被引量:2
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作者 Hao-Ling Zhang Rui Zhao +8 位作者 Di Wang Siti Nurfatimah Mohd Sapudin Badrul Hisham Yahaya Mohammad Syamsul Reza Harun Zhong-Wen Zhang Zhi-Jing Song Yan-Ting Liu Sandai Doblin Ping Lu 《World Journal of Clinical Oncology》 2025年第4期195-279,共85页
BACKGROUND Emerging evidence implicates Candida albicans(C.albicans)in human oncogenesis.Notably,studies have supported its involvement in regulating outcomes in colorectal cancer(CRC).This study investigated the para... BACKGROUND Emerging evidence implicates Candida albicans(C.albicans)in human oncogenesis.Notably,studies have supported its involvement in regulating outcomes in colorectal cancer(CRC).This study investigated the paradoxical role of C.albicans in CRC,aiming to determine whether it promotes or suppresses tumor development,with a focus on the mechanistic basis linked to its metabolic profile.AIM To investigate the dual role of C.albicans in the development and progression of CRC through metabolite profiling and to establish a prognostic model that integrates the microbial and metabolic interactions in CRC,providing insights into potential therapeutic strategies and clinical outcomes.METHODSA prognostic model integrating C. albicans with CRC was developed, incorporating enrichment analysis, immuneinfiltration profiling, survival analysis, Mendelian randomization, single-cell sequencing, and spatial transcriptomics.The effects of the C. albicans metabolite mixture on CRC cells were subsequently validated in vitro. Theprimary metabolite composition was characterized using liquid chromatography-mass spectrometry.RESULTSA prognostic model based on five specific mRNA markers, EHD4, LIME1, GADD45B, TIMP1, and FDFT1, wasestablished. The C. albicans metabolite mixture significantly reduced CRC cell viability. Post-treatment analysisrevealed a significant decrease in gene expression in HT29 cells, while the expression levels of TIMP1, EHD4, andGADD45B were significantly elevated in HCT116 cells. Conversely, LIME1 expression and that of other CRC celllines showed reductions. In normal colonic epithelial cells (NCM460), GADD45B, TIMP1, and FDFT1 expressionlevels were significantly increased, while LIME1 and EHD4 levels were markedly reduced. Following metabolitetreatment, the invasive and migratory capabilities of NCM460, HT29, and HCT116 cells were reduced. Quantitativeanalysis of extracellular ATP post-treatment showed a significant elevation (P < 0.01). The C. albicans metabolitemixture had no effect on reactive oxygen species accumulation in CRC cells but led to a reduction in mitochondrialmembrane potential, increased intracellular lipid peroxidation, and induced apoptosis. Metabolomic profilingrevealed significant alterations, with 516 metabolites upregulated and 531 downregulated.CONCLUSIONThis study introduced a novel prognostic model for CRC risk assessment. The findings suggested that the C.albicans metabolite mixture exerted an inhibitory effect on CRC initiation. 展开更多
关键词 Candida albicans Colorectal cancer Metabolic characteristics Extracellular ATP Prognostic model
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Influence of different data selection criteria on internal geomagnetic field modeling 被引量:4
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作者 HongBo Yao JuYuan Xu +3 位作者 Yi Jiang Qing Yan Liang Yin PengFei Liu 《Earth and Planetary Physics》 2025年第3期541-549,共9页
Earth’s internal core and crustal magnetic fields,as measured by geomagnetic satellites like MSS-1(Macao Science Satellite-1)and Swarm,are vital for understanding core dynamics and tectonic evolution.To model these i... Earth’s internal core and crustal magnetic fields,as measured by geomagnetic satellites like MSS-1(Macao Science Satellite-1)and Swarm,are vital for understanding core dynamics and tectonic evolution.To model these internal magnetic fields accurately,data selection based on specific criteria is often employed to minimize the influence of rapidly changing current systems in the ionosphere and magnetosphere.However,the quantitative impact of various data selection criteria on internal geomagnetic field modeling is not well understood.This study aims to address this issue and provide a reference for constructing and applying geomagnetic field models.First,we collect the latest MSS-1 and Swarm satellite magnetic data and summarize widely used data selection criteria in geomagnetic field modeling.Second,we briefly describe the method to co-estimate the core,crustal,and large-scale magnetospheric fields using satellite magnetic data.Finally,we conduct a series of field modeling experiments with different data selection criteria to quantitatively estimate their influence.Our numerical experiments confirm that without selecting data from dark regions and geomagnetically quiet times,the resulting internal field differences at the Earth’s surface can range from tens to hundreds of nanotesla(nT).Additionally,we find that the uncertainties introduced into field models by different data selection criteria are significantly larger than the measurement accuracy of modern geomagnetic satellites.These uncertainties should be considered when utilizing constructed magnetic field models for scientific research and applications. 展开更多
关键词 Macao Science Satellite-1 SWARM geomagnetic field modeling data selection core field crustal field
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3D crustal density modeling of Egypt using GOCE satellite gravity data and seismic integration 被引量:1
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作者 Moataz Sayed Mohamed Sobh +2 位作者 Salah Saleh Amal Othman Ahmed Elmahmoudi 《Earthquake Science》 2025年第2期110-125,共16页
A 3D crustal model was constructed using a combination of cutting-edge techniques,which were integrated to provide a density model for Egypt and address the sporadic distribution of seismic data.These techniques inclu... A 3D crustal model was constructed using a combination of cutting-edge techniques,which were integrated to provide a density model for Egypt and address the sporadic distribution of seismic data.These techniques include obtaining gravity data from the Gravity Field and Steady-State Ocean Circulation Explorer(GOCE),creating seismic profiles,analyzing the receiver functions of seismic data,obtaining information from boreholes,and providing geological interpretations.GOCE satellite gravity data were processed to construct a preliminary model based on nonlinear inversions of the data.A regional crustal thickness model was developed using receiver functions,seismic refraction profiles,and geological insights.The inverted model was validated using borehole data and compared with seismic estimates.The model exhibited strong consistency and revealed a correlation between crustal thickness,geology,and tectonics of Egypt.It showed that the shallowest depths of the Moho are located in the north along the Mediterranean Sea and in the eastern part along the Red Sea,reflecting an oceanic plate with a thin,high-density crust.The deepest Moho depths are located in the southwestern part of Egypt,Red Sea coastal mountains,and Sinai Peninsula.The obtained 3D model of crustal thickness provided finely detailed Moho depth estimates that aligned closely with geology and tectonic characteristics of Egypt,contributing valuable insights into the subsurface structure and tectonic processes of region. 展开更多
关键词 GOCE satellite gravity Moho depth crustal modeling gravity inversion
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Phase field modeling of the aspect ratio dependent functional properties of NiTi shape memory alloys with different grain sizes 被引量:1
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作者 Bo Xu Beihai Huang +1 位作者 Chong Wang Qingyuan Wang 《Acta Mechanica Sinica》 2025年第1期22-41,共20页
It is well known that coarse-grained super-elastic NiTi shape memory alloys(SMAs)exhibit localized rather than homogeneous martensite transformation(MT),which,however,can be strongly influenced by either internal size... It is well known that coarse-grained super-elastic NiTi shape memory alloys(SMAs)exhibit localized rather than homogeneous martensite transformation(MT),which,however,can be strongly influenced by either internal size(grain size,GS)or the external size(geometric size).The coupled effect of GS and geometric size on the functional properties has not been clearly understood yet.In this work,the super-elasticity,one-way,and stress-assisted two-way shape memory effects of the polycrystalline NiTi SMAs with different aspect ratios(length/width for the gauge section)and different GSs are investigated based on the phase field method.The coupled effect of the aspect ratio and GS on the functional properties is adequately revealed.The simulated results indicate that when the aspect ratio is lower than about 4:1,the stress biaxiality and stress heterogeneity in the gauge section of the sample become more and more obvious with decreasing the aspect ratio,which can significantly influence the microstructure evolution in the process involving external stress.Therefore,the corresponding functional property is strongly dependent on the aspect ratio.With decreasing the GS and the aspect ratio(to be lower than 4:1),both the aspect ratio and GS can affect the MT or martensite reorientation in each grain and the interaction among grains.Thus,due to the strong internal constraint(i.e.,the constraint of grain boundary)and the external constraint(i.e.,the constraint of geometric boundary),the capabilities of the functional properties of NiTi SMAs are gradually weakened and highly dependent on these two factors. 展开更多
关键词 Phase field modeling NITI Aspect ratio Grain size Functional property
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Modeling and sliding mode control based on inverse compensation of piezo-positioning system
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作者 LI Zhi-bin XIN Yuan-ze +1 位作者 ZHANG Jian-qiang SUN Chong-shang 《中国光学(中英文)》 北大核心 2025年第1期170-185,共16页
In order to enhance the control performance of piezo-positioning system,the influence of hysteresis characteristics and its compensation method are studied.Hammerstein model is used to represent the dynamic hysteresis... In order to enhance the control performance of piezo-positioning system,the influence of hysteresis characteristics and its compensation method are studied.Hammerstein model is used to represent the dynamic hysteresis nonlinear characteristics of piezo-positioning actuator.The static nonlinear part and dynamic linear part of the Hammerstein model are represented by models obtained through the Prandtl-Ishlinskii(PI)model and Hankel matrix system identification method,respectively.This model demonstrates good generalization capability for typical input frequencies below 200 Hz.A sliding mode inverse compensation tracking control strategy based on P-I inverse model and integral augmentation is proposed.Experimental results show that compared with PID inverse compensation control and sliding mode control without inverse compensation,the sliding mode inverse compensation control has a more ideal step response and no overshoot,moreover,the settling time is only 6.2 ms.In the frequency domain,the system closed-loop tracking bandwidth reaches 119.9 Hz,and the disturbance rejection bandwidth reaches 86.2 Hz.The proposed control strategy can effectively compensate the hysteresis nonlinearity,and improve the tracking accuracy and antidisturbance capability of piezo-positioning system. 展开更多
关键词 piezo-positioning system hysteresis nonlinearity Hammerstein model Prandtl-Ishlinskii(P-I)model system identification sliding mode control
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Millimeter-wave modeling based on transformer model for InP high electron mobility transistor
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作者 ZHANG Ya-Xue ZHANG Ao GAO Jian-Jun 《红外与毫米波学报》 北大核心 2025年第4期534-539,共6页
In this paper,the small-signal modeling of the Indium Phosphide High Electron Mobility Transistor(InP HEMT)based on the Transformer neural network model is investigated.The AC S-parameters of the HEMT device are train... In this paper,the small-signal modeling of the Indium Phosphide High Electron Mobility Transistor(InP HEMT)based on the Transformer neural network model is investigated.The AC S-parameters of the HEMT device are trained and validated using the Transformer model.In the proposed model,the eight-layer transformer encoders are connected in series and the encoder layer of each Transformer consists of the multi-head attention layer and the feed-forward neural network layer.The experimental results show that the measured and modeled S-parameters of the HEMT device match well in the frequency range of 0.5-40 GHz,with the errors versus frequency less than 1%.Compared with other models,good accuracy can be achieved to verify the effectiveness of the proposed model. 展开更多
关键词 transformer model neural network high electron mobility transistor(HEMT) small signal model
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Cumulative thermal coupling modeling and analysisof oil-immersed motor-pump assembly forelectro–hydrostatic actuator 被引量:1
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作者 Siming FAN Shaoping WANG +3 位作者 Qiyang WANG Xingjian WANG Di LIU Xiao WU 《Chinese Journal of Aeronautics》 2025年第5期394-410,共17页
The Electro–Hydrostatic Actuator(EHA)is applied to drive the control surface in flightcontrol system of more electric aircraft.In EHA,the Oil-Immersed Motor Pump(OMP)serves asthe core as a power assembly.However,the ... The Electro–Hydrostatic Actuator(EHA)is applied to drive the control surface in flightcontrol system of more electric aircraft.In EHA,the Oil-Immersed Motor Pump(OMP)serves asthe core as a power assembly.However,the compact integration of the OMP presents challenges inefficiently dissipating internal heat,leading to a performance degradation of the EHA due to ele-vated temperatures.Therefore,accurately modeling and predicting the internal thermal dynamicsof the OMP hold considerable significance for monitoring the operational condition of the EHA.In view of this,a modeling method considering cumulative thermal coupling was hereby proposed.Based on the proposed method,the thermal models of the motor and the pump were established,taking into account heat accumulation and transfer.Taking the leakage oil as the heat couplingpoint between the motor and the pump,the dynamic thermal coupling model of the OMP wasdeveloped,with the thermal characteristics of the oil considered.Additionally,the comparativeexperiments were conducted to illustrate the efficiency of the proposed model.The experimentalresults demonstrate that the proposed dynamic thermal coupling model accurately captured thethermal behavior of OMP,outperforming the static thermal parameter model.Overall,thisadvancement is crucial for effectively monitoring the health of EHA and ensuring flight safety. 展开更多
关键词 Electro-hydrostatic actuator Oil-immersed motor-pump Dynamic thermal coupling model Heat transfer Heat accumulation
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Undrained mechanical behavior of unsaturated completely weathered granite:Experimental investigation and constitutive modeling 被引量:1
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作者 DU Shao-hua MA Jin-yin +2 位作者 RUAN Bo WU Gen-shui ZHANG Rui-chao 《Journal of Central South University》 2025年第6期2307-2327,共21页
The undrained mechanical behavior of unsaturated completely weathered granite(CWG)is highly susceptible to alterations in the hydraulic environment,particularly under uniaxial loading conditions,due to the unique natu... The undrained mechanical behavior of unsaturated completely weathered granite(CWG)is highly susceptible to alterations in the hydraulic environment,particularly under uniaxial loading conditions,due to the unique nature of this soil type.In this study,a series of unconfined compression tests were carried out on unsaturated CWG soil in an underground engineering site,and the effects of varying the environmental variables on the main undrained mechanical properties were analyzed.Based on the experimental results,a novel constitutive model was then established using the damage mechanics theory and the undetermined coefficient method.The results demonstrate that the curves of remolded CWG specimens with different moisture contents and dry densities exhibited diverse characteristics,including brittleness,significant softening,and ductility.As a typical indicator,the unconfined compression strength of soil specimens initially increased with an increase in moisture content and then decreased.Meanwhile,an optimal moisture content of approximately 10.5%could be observed,while a critical moisture content value of 13.0%was identified,beyond which the strength of the specimen decreases sharply.Moreover,the deformation and fracture of CWG specimens were predominantly caused by shear failure,and the ultimate failure modes were primarily influenced by moisture content rather than dry density.Furthermore,by comparing several similar models and the experimental data,the proposed model could accurately replicate the undrained mechanical characteristics of unsaturated CWG soil,and quantitatively describe the key mechanical indexes.These findings offer a valuable reference point for understanding the underlying mechanisms,anticipating potential risks,and implementing effective control measures in similar underground engineering projects. 展开更多
关键词 completely weathered granite undrained mechanical behavior environmental variable unconfined compression test constitutive model
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Modeling and control of automatic voltage regulation for a hydropower plant using advanced model predictive control 被引量:1
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作者 Ebunle Akupan Rene Willy Stephen Tounsi Fokui 《Global Energy Interconnection》 2025年第2期269-285,共17页
Fluctuating voltage levels in power grids necessitate automatic voltage regulators(AVRs)to ensure stability.This study examined the modeling and control of AVR in hydroelectric power plants using model predictive cont... Fluctuating voltage levels in power grids necessitate automatic voltage regulators(AVRs)to ensure stability.This study examined the modeling and control of AVR in hydroelectric power plants using model predictive control(MPC),which utilizes an extensive mathe-matical model of the voltage regulation system to optimize the control actions over a defined prediction horizon.This predictive feature enables MPC to minimize voltage deviations while accounting for operational constraints,thereby improving stability and performance under dynamic conditions.Thefindings were compared with those derived from an optimal proportional integral derivative(PID)con-troller designed using the artificial bee colony(ABC)algorithm.Although the ABC-PID method adjusts the PID parameters based on historical data,it may be difficult to adapt to real-time changes in system dynamics under constraints.Comprehensive simulations assessed both frameworks,emphasizing performance metrics such as disturbance rejection,response to load changes,and resilience to uncertainties.The results show that both MPC and ABC-PID methods effectively achieved accurate voltage regulation;however,MPC excelled in controlling overshoot and settling time—recording 0.0%and 0.25 s,respectively.This demonstrates greater robustness compared to conventional control methods that optimize PID parameters based on performance criteria derived from actual system behavior,which exhibited settling times and overshoots exceeding 0.41 s and 5.0%,respectively.The controllers were implemented using MATLAB/Simulink software,indicating a significant advancement for power plant engineers pursuing state-of-the-art automatic voltage regulations. 展开更多
关键词 Automatic voltage regulation Artificial bee colony Evolutionary techniques Model predictive control PID controller HYDROPOWER
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Spatial Modeling of COVID-19 Occurrence and Vaccination Rate across Counties in Ohio State from Jan. 2020 to April 2023
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作者 Olawale Oluwafemi Oluwaseun Ibukun +3 位作者 Yaw Kwarteng Kehinde Adebowale Yahaya Danjuma Samson Mela 《Journal of Geographic Information System》 2025年第1期80-96,共17页
The study aims to investigate county-level variations of the COVID-19 disease and vaccination rate. The COVID-19 data was acquired from usafact.org, and the vaccination records were acquired from the Ohio vaccination ... The study aims to investigate county-level variations of the COVID-19 disease and vaccination rate. The COVID-19 data was acquired from usafact.org, and the vaccination records were acquired from the Ohio vaccination tracker dashboard. GIS-based exploratory analysis was conducted to select four variables (poverty, black race, population density, and vaccination) to explain COVID-19 occurrence during the study period. Consequently, spatial statistical techniques such as Moran’s I, Hot Spot Analysis, Spatial Lag Model (SLM), and Spatial Error Model (SEM) were used to explain the COVID-19 occurrence and vaccination rate across the 88 counties in Ohio. The result of the Local Moran’s I analysis reveals that the epicenters of COVID-19 and vaccination followed the same patterns. Indeed, counties like Summit, Franklin, Fairfield, Hamilton, and Medina were categorized as epicenters for both COVID-19 occurrence and vaccination rate. The SEM seems to be the best model for both COVID-19 and vaccination rates, with R2 values of 0.68 and 0.70, respectively. The GWR analysis proves to be better than Ordinary Least Squares (OLS), and the distribution of R2 in the GWR is uneven throughout the study area for both COVID-19 cases and vaccinations. Some counties have a high R2 of up to 0.70 for both COVID-19 cases and vaccinations. The outcomes of the regression analyses show that the SEM models can explain 68% - 70% of COVID-19 cases and vaccination across the entire counties within the study period. COVID-19 cases and vaccination rates exhibited significant positive associations with black race and poverty throughout the study area. 展开更多
关键词 COVID-19 Prevalence COVID-19 Vaccination OHIO Spatial Lag Model Spatial Error Model
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An alternative regularization approach for modeling the regional lithospheric magnetic field from satellite magnetic measurements by the spherical equivalent source method and its application in Africa 被引量:1
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作者 JiangSong Gui JinSong Du +5 位作者 Pan Zhang ChangQing Yuan YuKun Li KangAn Zhao Liang Yin HouPu Li 《Earth and Planetary Physics》 2025年第3期697-710,共14页
The equivalent source(ES)method in the spherical coordinate system has been widely applied to processing,reduction,field modeling,and geophysical and geological interpretation of satellite magnetic anomaly data.Howeve... The equivalent source(ES)method in the spherical coordinate system has been widely applied to processing,reduction,field modeling,and geophysical and geological interpretation of satellite magnetic anomaly data.However,the inversion for the ES model suffers from nonuniqueness and instability,which remain unresolved.To mitigate these issues,we introduce both the minimum and flattest models into the model objective function as an alternative regularization approach in the spherical ES method.We first present the methods,then analyze the accuracy of forward calculation and test the proposed ES method in this study by using synthetic data.The experimental results from simulation data indicate that our proposed regularization effectively suppresses the Backus effect and mitigates inversion instability in the low-latitude region.Finally,we apply the proposed method to magnetic anomaly data from China Seismo-Electromagnetic Satellite-1(CSES-1)and Macao Science Satellite-1(MSS-1)magnetic measurements over Africa by constructing an ES model of the large-scale lithospheric magnetic field.Compared with existing global lithospheric magnetic field models,our ES model demonstrates good consistency at high altitudes and predicts more stable fields at low altitudes.Furthermore,we derive the reduction to the pole(RTP)magnetic anomaly fields and the apparent susceptibility contrast distribution based on the ES model.The latter correlates well with the regional tectonic framework in Africa and surroundings. 展开更多
关键词 regional lithospheric magnetic field model spherical equivalent source method satellite magnetism AFRICA MSS-1 CSES-1
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Constitutive modeling to predict flow stress of AerMet 100 ultra-high strength steel in hot working process
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作者 Ri Sung Kim Kyong Ho Sim Hye Yong Ri 《Journal of Iron and Steel Research International》 2025年第9期2834-2846,共13页
The phenomenological and physically based models,using the true stress–true strain curve data obtained under various hot working conditions of 850–1200°C and 0.001–10 s−1,were developed and improved for AerMet... The phenomenological and physically based models,using the true stress–true strain curve data obtained under various hot working conditions of 850–1200°C and 0.001–10 s−1,were developed and improved for AerMet 100 ultra-high strength steel.The predictability of the developed constitutive models was verified and compared.The determination coefficient and average absolute relative error were 0.9988 and 3.72%for the improved version of the modified Zerilli–Armstrong model,0.9985 and 3.96%for the improved version of the modified Johnson–Cook model,0.9947 and 4.59%for the strain-compensated Arrhenius-type model and 0.9913 and 5.43%for the improved Khan–Huang–Liang model,respectively.The results showed that the improved versions of the modified Zerilli–Armstrong model have the best predictability among the studied constitutive models.Comparing the predictability before and after the improvement,the average absolute relative error was increased by 65.14%for the modified Zerilli–Armstrong model and 58.45%for the modified Johnson–Cook model.This indicates that the phenomenological improvement of physically based constitutive models allows us to develop effectively constitutive equations with high prediction accuracy. 展开更多
关键词 AerMet 100 steel High-temperature flow stress Arrhenius-type model Johnson-Cook model Khan-Huang-Liang model Zerilli-Armstrong model
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PIMS模型在炼化一体化企业的原油采购中的高效应用
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作者 范承德 《石油石化物资采购》 2025年第21期16-18,共3页
本文介绍了福建某炼化一体化企业利用PIMS软件优化现货原油选择的一种方法,在价格假设和产品约束等限制条件下,利用替代对比法找出经济性靠前的现货品种,再通过不同的现货组合找出经济性最优的组合,最后对影响现货原油经济性的因素进行... 本文介绍了福建某炼化一体化企业利用PIMS软件优化现货原油选择的一种方法,在价格假设和产品约束等限制条件下,利用替代对比法找出经济性靠前的现货品种,再通过不同的现货组合找出经济性最优的组合,最后对影响现货原油经济性的因素进行敏感性分析,最终确定现货原油的采购方案。福建某炼化一体化企业利用该方法成功采购了几十个现货原油,在满足装置稳定生产的情况下,均创造了巨大的经济效益。 展开更多
关键词 pimS模型 炼化一体化 现货原油 基准油 产品价差 乙烯原料
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A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis
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作者 Xiao Liang Xingping Quan +6 位作者 Xiaorui Geng Yujing Huang Yonghua Zhao Lei Xi Zhen Yuan Ping Wang Bin Liu 《Neural Regeneration Research》 SCIE CAS 2025年第7期2029-2037,共9页
To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral cortex.However,these me... To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral cortex.However,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly age-related.In this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed laser.We observed the molding process in mice of different ages and presented age-dependent vascular embolism differentiation.Moreover,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a stroke.Our imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes. 展开更多
关键词 AGE-DEPENDENT cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy PHOTOTHROMBOSIS vascular imaging
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Membranes of Polymer of Intrinsic Microporosity PIM-1 for Gas Separation:Modification Strategies and Meta-Analysis
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作者 Boya Qiu Yong Gao +1 位作者 Patricia Gorgojo Xiaolei Fan 《Nano-Micro Letters》 2025年第5期326-358,共33页
Polymers of intrinsic microporosity(PIMs)have received considerable attention for making high-performance membranes for carbon dioxide separation over the last two decades,owing to their highly permeable porous struct... Polymers of intrinsic microporosity(PIMs)have received considerable attention for making high-performance membranes for carbon dioxide separation over the last two decades,owing to their highly permeable porous structures.However,challenges regarding its relatively low selectivity,physical aging,and plasticisation impede relevant industrial adoptions for gas separation.To address these issues,several strategies including chain modification,post-modification,blending with other polymers,and the addition of fillers,have been developed and explored.PIM-1 is the most investigated PIMs,and hence here we review the stateof-the-arts of the modification strategies of PIM-1 critically and discuss the progress achieved for addressing the aforementioned challenges via meta-analysis.Additionally,the development of PIM-1-based thin film composite membranes is commented as well,shedding light on their potential in industrial gas separation.We hope that the review can be a timely snapshot of the relevant state-of-the-arts of PIMs guiding future design and optimisation of PIMs-based membranes for enhanced performance towards a higher technology readiness level for practical applications. 展开更多
关键词 Polymers of intrinsic microporosity(pims) pim-1 Gas separation META-ANALYSIS Upper bound
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