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Chinese Journal of Polymer Science 2017年第12期35卷 1497-1507页

作者： yi-lan guo Run-zhi Zhang Kai Wu 陈枫傅强 College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University

In this article, hybrid fillers with different dimensions, namely, 2-dimensional（2-D） expanded graphite（EG） and 1-dimensional（1-D） multi-walled carbon nanotubes（CNTs）, were added to aromatic nylon MXD6 matrix via melt-blending, to enhance its thermal and electrical conductivity as well as electromagnetic interference shielding effectiveness（EMI SE）. For ternary composites of MXD6/EG/CNTs, the electrical conductivity reaches up nine orders of magnitude higher compared to that of the neat MXD6 sample, which turned the polymer-based composites from an insulator to a conductor, and the thermal conductivity has been enhanced by 477% compared with that of neat MXD6 sample. Meanwhile, the EMI SE of ternary composite reaches ~50 d B at the overall filler loading of only 18 wt%. This work can provide guidance for the preparation of polymer composites with excellent thermal and electrical conductivity via using hybrid filler.

关键词： Thermal and electrical conductivity Electromagnetic interference shielding Hybrid filler Synergistic effect

Towards High Molecular Weight Poly(bisphenol A carbonate) with Excellent Thermal Stability and Mechanical Properties by Solid-State Polymerization

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Chinese Journal of Polymer Science 2015年第8期33卷 1176-1185页

作者： Yu-ling He yi-lan guo Rui He Tian-xiang Jin 陈枫傅强 Nan Zhou Ji Shen College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University China Bluestar Chengrand Chemical Co. Ltd.

Poly（bisphenol A carbonate）（BPA-PC） was post-polymerized by solid-state polymerization （SSP） after supercritical CO2-induced crystallization in low molecular weight particles prepolymerized via melt transesterification reaction. The effects of the crystallization conditions on melting behavior and SSP of BPA-PC were investigated with differential scanning calorimetry （DSC）, Ubbelohde viscosity method and gel permeation chromatography （GPC）. The reaction kinetics of the SSP of crystallized prepolymers was studied as a function of reaction temperatures for various reaction periods. As a result, the viscosity average molecular weight of BPA-PC particles （2 mm） increased from 1.9 × 10^4 g/mol to 2.8 × 10^4 g/mol after SSP. More importantly, the significantly enhanced thermal stability and mechanical properties of solid-state polymerized BPA-PC, compared with those of melt transesterification polymerized BPA-PC with the same molecular weight, can be ascribed to the substantial avoidance of undergoing high temperature during polymerization. Our work provides a useful method to obtain practical product of BPA-PC with high quality and high molecular weight.

关键词： Poly(bisphenol A carbonate) Solid-state polymerization Supercritical C02-induced crystallization Highmolecular weight High quality.

Laser image refractive index sensor based on the combination of a coreless optical fiber and a digital camera

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Optoelectronics Letters 2025年第2期21卷 65-68页

作者： guo Jingzhong lan Feng CHEN Xiang LIU Haifeng Xi’an Institute of Space Radio Technology Xi’an 710100China Key Laboratory of Optoelectronic Sensor and Sensing Network Technology College of Electronic Information and Optical EngineeringNankai UniversityTianjin 300350China

As a laser passes through a scattering medium,the light interacts with the irregular reflections within the medium,resulting in light scattering and the formation of *** this paper,an image sensor based on the combination of a coreless optical fiber and a digital camera is proposed for liquid refractive index sensing *** coreless fiber is used as a sensing unit,and the change in the speckle pattern is measured using the digital correlation method to detect the magnitude of the liquid's refractive *** experimental results indicate that the laser image sensing technique is capable of effectively distinguishing liquid samples with refractive indices ranging from 1.332 8 to1.390 8,with a sensing sensitivity of-1.306 ***,the laser image sensing technique,with its advantages of high experimental reproducibility,simple system design,remote over-control,holds great research significance and potential application in laser communication and sensor integration.

关键词： fiber scattering optical

Constrained Networked Predictive Control for Nonlinear Systems Using a High-Order Fully Actuated System Approach

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 478-480页

作者： yi Huang guo-Ping Liu yi Yu Wenshan Hu the School of Electrical Engineering and Automation Wuhan University IEEE the Center for Control Science and Technology Southern University of Science and Technology the Department of Electrical and Electronic Engineering The Hong Kong Polytechnic University

Dear Editor,In this letter, a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated (HOFA) systems with noises. The method can effectively deal with nonlinearities, constraints, and noises in the system, optimize the performance metric, and present an upper bound on the stable output of the system.

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The detection,extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 82-92页

作者： Qianyun Yun Wen-Biao Han yi-Yang guo He Wang Minghui Du Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310124China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Taiji Laboratory for Gravitational Wave Universe(Beijing/Hangzhou) University of Chinese Academy of SciencesBeijing 100049China lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu ProvinceKey Laboratory of Quantum Theory and Applications of MoELanzhou UniversityLanzhou 730000China Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China International Centre for Theoretical Physics Asia-Pacific(ICTP-AP) University of Chinese Academy of Sciences(UCAS)Beijing 100049China Center for Gravitational Wave Experiment National Microgravity LaboratoryInstitute of MechanicsChinese Academy of SciencesBeijing 100190China

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EM-RIs).This task is particularly challenging because EMRI signals are complex,lengthy,and *** this work,we introduce a 2-layer convolutional neural network(CNN)approach to detect EMRI signals for space-borne detectors,achieving a true positive rate(TPR)of 96.9%at a 1%false positive rate(FPR)for signal-to-noise ratio(SNR)from 50 to ***,the key intrinsic parameters of EMRIs such as the mass,spin of the supermassive black hole(SMBH)and the initial eccentricity of the orbit can also be inferred directly by employing a neural *** mass and spin of the SMBH can be determined at 99%and 92%*** will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform *** study underscores the potential of deep learning methods in EMRI data analysis,enabling the rapid detection of EMRI signals and efficient parameter estimation.

关键词： gravitational wave EMRIs deep-learing

New Insights on Gamma-Ray Burst Radiation Mechanisms from Multiwavelength Observations

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Research in Astronomy and Astrophysics 2025年第2期25卷 3-12页

作者： Yu-Hua Yao Fang-Sheng Min Shi Chen yi-Qing guo College of Physics Chongqing University Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Wisconsin Ice Cube Particle Astrophysics Center University of Wisconsin–Madison University of Chinese Academy of Sciences School of Physics and Astronomy Yunnan University Tianfu Cosmic Ray Research Center

The study of high-energy gamma-ray emission from gamma-ray bursts(GRBs) involves complex synchrotron radiation and synchrotron self-Compton(SSC) scattering mechanisms with multiple parameters exhibiting a wide distribution. Recent advancements in GRB research, particularly the observation of very high energy(VHE,>100 Ge V) radiation, have ushered in a new era of multiwavelength exploration, offering fresh perspectives and limitations for understanding GRB radiation mechanisms. This study aimed to leverage VHE observations to refine constraints on synchrotron + SSC radiation from electrons accelerated by forward shocks. By analyzing two external environments—the uniform interstellar medium and stratified stellar wind medium, we conducted spectral and variability fitting for five specific bursts(GRB 180720B, GRB 190114C, GRB 190829A, GRB 201216C, and GRB 221009A) to identify the optimal parameters characterizing these events. A comparative analysis of model parameter distributions with and without VHE radiation observations reveals that the magnetic energy equipartition factor εBis more concentrated with VHE emissions. This suggests that VHE emissions may offer greater constraints on this microphysical parameter. Additionally, we found that the energy budget between VHE and ke V–Me V γ-ray emissions under the SSC radiation exhibits an almost linear relationship, which may serve as a tool to differentiate radiation mechanisms. We anticipate future statistical analyses of additional VHE bursts to validate our findings.

关键词： (transients:) gamma-ray bursts gamma-rays: ISM radiation mechanisms: non-thermal

Polypropylene-based blend with enhanced breakdown strength under gamma-ray irradiation for cable insulation

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Nuclear Science and Techniques 2025年第1期36卷 35-48页

作者： Bai-Xin Liu Yu Gao Jing Li Chen-yi guo Bo-Sen Si Jun-guo Gao Yu Chen Bo-Xue Du School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an 710049China

This study focuses on the electrical properties and microstructure of polypropylene(PP)-based blends used for cable insulation in nuclear power plants(NPPs).The PP-based blend,comprising isotactic PP and propylene-based elastomer(PBE)at concentrations ranging from 0 to 50 wt%,underwent a melt blending process and subsequent cobalt-60 gamma-ray irradiation with doses ranging from 0 to 250 *** conductivity,trap distribution,and alternating(AC)breakdown strength were chosen to assess the insulation *** results indicate that the addition of PBE significantly improves the electrical properties of PP under *** PP,the electrical conductivity increased with irradiation,whereas the trap depth and breakdown strength decreased ***,for the blend,these changes initially exhibit opposite *** the irradiation was increased to 250 kGy,the AC breakdown strength of the blend improved by more than 21%compared to that of *** physical and chemical structures of the samples were investigated to explore the improvement *** results offer insights into the design of new cable-insulation materials suitable for NPPs.

关键词： Nuclear power plant Cable insulation Polypropylene Electrical properties Gamma-ray irradiation

Forecasting step-like landslide displacement through diverse monitoring frequencies

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Journal of Mountain Science 2025年第1期22卷 122-141页

作者： guo Fei XU Zhizhen HU Jilei DOU Jie LI Xiaowei yi Qinglin Key Laboratory of Geological Hazards on Three Gorges Reservoir Area(China Three Gorges University) Ministry of EducationYichang 443002China College of Civil Engineering&Architecture China Three Gorges UniversityYichang 443002China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China Central-South Institute of Metallurgical Geology Yichang 443003China Xi’an Railway Bridge Engineering CO. LTD of China Railway Seventh GroupXi’an 710032China

The precision of landslide displacement prediction is crucial for effective landslide prevention and mitigation ***,the role of surface monitoring frequency in influencing prediction accuracy has been largely *** study examined the effect of varying monitoring frequencies on the accuracy of displacement predictions by using the Baijiabao landslide in the Three Gorges Reservoir Area(TGRA)as a case *** collected surface automatic monitoring data at different intervals,ranging from daily to *** Ensemble Empirical Mode Decomposition(EEMD)algorithm was utilized to dissect the accumulated displacements into periodic and trend components at each monitoring *** fitting was applied to forecast the trend component while the periodic component was predicted with two state-of-the-art neural network models:Long Short-Term Memory(LSTM)and Gated Recurrent Unit(GRU).The predictions from these models were integrated to derive cumulative displacement forecasts,enabling a comparative analysis of prediction accuracy across different monitoring *** results demonstrate that the proposed models achieve high accuracy in landslide displacement forecasting,with optimal performance observed at moderate monitoring ***,the daily mean average error(MAE)decreases sharply with increasing monitoring frequency,reaching a *** findings were corroborated by a parallel analysis of the Bazimen landslide,suggesting that moderate monitoring intervals of approximately 7 to 15 days are most conducive to achieving enhanced prediction accuracy compared to both daily and monthly intervals.

关键词： Three Gorges Reservoir Area Step-like landslide Different monitoring frequencies EEMD algorithm GRU predictive model

Modeling of Spring Phenology of Boreal Forest by Coupling Machine Learning and Diurnal Temperature Indicators

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Chinese Geographical Science 2025年第1期35卷 38-54页

作者： DENG guorong ZHANG Hongyan HONG ying guo Xiaoyi yi Zhihua EHSAN BINIYAZ School of Hydraulic Engineering Nanchang Institute of TechnologyNanchang 330099China Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024China Urban Remote Sensing Application Innovation Center School of Geographical SciencesNortheast Normal UniversityChangchun 130024China School of Geographical Sciences Inner Mongolia Normal UniversityHohhot 010022China landscape Ecology and Geoinformation Science Department of GeographyKiel UniversityKiel 24118Germany

The roles of diurnal temperature in providing heat accumulation and chilling requirements for vegetation spring phenology *** previous studies have established a stronger correlation between leaf onset and diurnal temperature than between leaf onset and average temperature,current research on modeling spring phenology based on diurnal temperature indicators remains *** this study,we confirmed the start of the growing season(SOS)sensitivity to diurnal temperature and average temperature in boreal *** estimation of SOS was carried out by employing K-Nearest Neighbor Regression(KNR-TDN)model,Random Forest Regres-sion(RFR-TDN)model,eXtreme Gradient Boosting(XGB-TDN)model and Light Gradient Boosting Machine model(LightGBM-TDN)driven by diurnal temperature indicators during 1982-2015,and the SOS was projected from 2015 to 2100 based on the Coupled Model Intercomparison Project Phase 6(CMIP6)climate scenario *** sensitivity of boreal forest SOS to daytime temperature is greater than that to average temperature and nighttime *** LightGBM-TDN model perform best across all vegetation types,exhibiting the lowest RMSE and bias compared to the KNR-TDN model,RFR-TDN model and XGB-TDN *** incorporating diurn-al temperature indicators instead of relying only on average temperature indicators to simulate spring phenology,an improvement in the accuracy of the model is ***,the preseason accumulated daytime temperature,daytime temperature and snow cover end date emerged as significant drivers of the SOS simulation in the study *** simulation results based on LightGBM-TDN model exhibit a trend of advancing SOS followed by stabilization under future climate *** study underscores the potential of diurn-al temperature indicators as a viable alternative to average temperature indicators in driving spring phenology models,offering a prom-ising new method for simulating spring phenology.

关键词： spring phenology diurnal temperature machine learning future climate scenarios boreal forest

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基于直觉模糊集的企业动态能力测量

系统工程 2016年第12期34卷 135-145页

作者：戴亦兰张卫国华南理工大学工商管理学院广东广州510641 北京师范大学珠海分校国际商学部广东珠海519087

在梳理文献的基础上,首先通过专家调查法筛选出了关于企业动态能力测量的关键指标。然后,利用直觉模糊集的相关理论,将语言短语形式的指标权重、数值和语言短语形式的评价信息转化为直觉模糊数的形式,通过计算方案的综合评价值、群体综... 详细信息

在梳理文献的基础上,首先通过专家调查法筛选出了关于企业动态能力测量的关键指标。然后,利用直觉模糊集的相关理论,将语言短语形式的指标权重、数值和语言短语形式的评价信息转化为直觉模糊数的形式,通过计算方案的综合评价值、群体综合评价值及最终的优势度,获得动态能力评分的排序。文章通过电子商务企业的实例验证了直觉模糊集在动态能力测量的可行性和有效性。

关键词：动态能力直觉模糊集直觉模糊数犹豫度