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Determination of global geodetic parameters using satellite laser ranging to Galileo,GLONASS,and BeiDou satellites

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Satellite Navigation 2024年第1期5卷 240-257页

作者： Xingxing Li jiaqing Lou Yongqiang Yuan jiaqi Wu Keke zhang School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079HubeiChina

The new Global Navigation Satellite System(GNSS)satellites,including GLONASS,Galileo,and BeiDou system,are equipped with Laser Retroreflector Arrays(LRA)to support Satellite Laser Ranging(SLR)tracking,which contributes to the estimation of global geodetic *** this study,we estimate the global geodetic parameters using the SLR observations to GNSS satellites and also investigate the effects of different data processing strategies on the estimated Earth Rotation Parameters(ERP),geocenter motion,and terrestrial *** results indicate that setting range bias parameters for each satellite-station pair can effectively account for the satellite-specific biases induced by LRAs,leading to smaller Root Mean Square Errors(RMSE)of the post-fit SLR ***,estimating the range biases for each satellite-station pair improves the accuracy of the estimated station coordinates and *** also examine the impact of different arc lengths on the estimates of ERP,geocenter motion,and terrestrial *** results show that extending arc length can significantly reduce the formal error of *** 7-day strategy produces the smallest RMSEs of 473 microarcseconds and 495 microarcseconds for the estimated X-and Y-component of pole coordinates,and 52 microseconds for length-of-day,***,the estimated geocenter motion is less affected by the arc length,even the shortest 1-day arc strategy can capture the seasonal variations of geocenter motion in z *** scale estimation,extending the arc length notably improves the accuracy of the estimated station coordinates and scale,but this advantage becomes less noticeable in longer *** 7-day solution also obtains the closet scale results compared to ITRF2014,with the RMSE of 2.10×10^(–9).

关键词： Satellite laser ranging GNSS Geodetic parameters Earth rotation parameters Geocenter motion Terrestrial scale

Eat at the right time: Regulation of ER-phagy receptors in plant response to environmental stresses

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Molecular Plant 2024年第2期17卷 236-239页

作者： Yang Shao jiaqi Sun Huanquan zheng The Key Laboratory of Plant Development and Environmental Adaptation Biology Ministry of EducationSchool of Life SciencesShandong UniversityQingdao 266237China Department of Biology McGill UniversityMontrealQC H3A 1B1Canada

The endoplasmic reticulum(ER)is a cellular factory for biosynthesis of proteins and *** accommodate a wide array of biosynthetic demands in responses to environmental stresses,the plant ER remodels to maintain a structural and functional homeostasis.A key process facilitating this balance is selective autophagy of the ER(ER-phagy),where malfunctioned ER is recognized,engulfed by autophagosomes,and then delivered to the vacuole for degradation.

关键词： maintain accommodate function

Cost-Sensitive Dual-Stream Residual Networks for Imbalanced Classification

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Computers, Materials & Continua 2024年第9期80卷 4243-4261页

作者： Congcong Ma jiaqi Mi Wanlin Gao Sha Tao College of Information and Electrical Engineering China Agricultural UniversityBeijing100083China Key Laboratory of Agricultural Informatization Standardization Ministry of Agriculture and Rural AffairsChina Agricultural UniversityBeijing100083China

Imbalanced data classification is the task of classifying datasets where there is a significant disparity in the number of samples between different *** task is prevalent in practical scenarios such as industrial fault diagnosis,network intrusion detection,cancer detection,*** imbalanced classification tasks,the focus is typically on achieving high recognition accuracy for the minority ***,due to the challenges presented by imbalanced multi-class datasets,such as the scarcity of samples in minority classes and complex inter-class relationships with overlapping boundaries,existing methods often do not perform well in multi-class imbalanced data classification tasks,particularly in terms of recognizing minority classes with high ***,this paper proposes a multi-class imbalanced data classification method called CSDSResNet,which is based on a cost-sensitive dualstream residual ***,to address the issue of limited samples in the minority class within imbalanced datasets,a dual-stream residual network backbone structure is designed to enhance the model’s feature extraction ***,considering the complexities arising fromimbalanced inter-class sample quantities and imbalanced inter-class overlapping boundaries in multi-class imbalanced datasets,a unique cost-sensitive loss function is *** loss function places more emphasis on the minority class and the challenging classes with high interclass similarity,thereby improving the model’s classification ***,the effectiveness and generalization of the proposed method,CSDSResNet,are evaluated on two datasets:‘DryBeans’and‘Electric Motor Defects’.The experimental results demonstrate that CSDSResNet achieves the best performance on imbalanced datasets,with macro_F1-score values improving by 2.9%and 1.9%on the two datasets compared to current state-of-the-art classification methods,***,it achieves the highest precision in single-class r

关键词： Deep learning imbalanced data classification fault diagnosis cost-sensitivity

Pyramid Separable Channel Attention Network for Single Image Super-Resolution

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Computers, Materials & Continua 2024年第9期80卷 4687-4701页

作者： Congcong Ma jiaqi Mi Wanlin Gao Sha Tao College of Information and Electrical Engineering China Agricultural UniversityBeijing100083China College of Artificial Intelligence Nankai UniversityTianjin300350China Key Laboratory of Agricultural Informatization Standardization Ministry of Agriculture and Rural AffairsChina Agricultural UniversityBeijing100083China

Single Image Super-Resolution(SISR)technology aims to reconstruct a clear,high-resolution image with more information from an input low-resolution image that is blurry and contains less *** technology has significant research value and is widely used in fields such as medical imaging,satellite image processing,and security *** significant progress in existing research,challenges remain in reconstructing clear and complex texture details,with issues such as edge blurring and artifacts still *** visual perception effect still needs further ***,this study proposes a Pyramid Separable Channel Attention Network(PSCAN)for the SISR *** designs a convolutional backbone network composed of Pyramid Separable Channel Attention blocks to effectively extract and fuse multi-scale *** expands the model’s receptive field,reduces resolution loss,and enhances the model’s ability to reconstruct texture ***,an innovative artifact loss function is designed to better distinguish between artifacts and real edge details,reducing artifacts in the reconstructed *** conducted comprehensive ablation and comparative experiments on the Arabidopsis root image dataset and several public *** experimental results show that the proposed PSCAN method achieves the best-known performance in both subjective visual effects and objective evaluation metrics,with improvements of 0.84 in Peak Signal-to-Noise Ratio(PSNR)and 0.017 in Structural Similarity Index(SSIM).This demonstrates that the method can effectively preserve high-frequency texture details,reduce artifacts,and have good generalization performance.

关键词： Deep learning single image super-resolution artifacts texture details

Solid particle size characterization by a high-frequency collision response in pneumatic particulate flow

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Particuology 2024年第3期86卷 39-54页

作者： Kai Wang Yichen Li ziang Chang Min Qin Guangming Fu Bangtang Yin Gang Wang jiaqi Tian School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580China Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Ministry of EducationQingdao266580China National Engineering Research Center of Oil&Gas Drilling and Completion Technology Qingdao266580China Shock and Vibration of Engineering Materials and Structures Key Lab ofSichuan Province Southwest University of Science and TechnologyMianyang621000China

A novel triaxial vibration method is developed for the real-time characterization of the solid particle size distribution(PsD)in pneumatic particulate flow,which is critical for chemical *** this work,the particle-wall collision and friction behaviours were analysed by the time-domain statistical and timefrequency joint methods to narrow the high-frequency response range by the initial experiment of free fall for a single particle,interparticle,and multiple ***,verification experiments of PSD characterization in pneumatic flow were ***,the quantitative triaxial energy response model that considers the particle size,shape,and mass factors were ***,a good agreement of the particle number identification was found between the triaxial vibration energy and mean particle size of 150-550μ***,the performance with the best accuracy was focused on a range of 42-43 kHz in the x-axis and z-axis and 36.8-38.8 kHz in the ***,the individual particle energy was inversely analysed by the triaxial vibration response within the optimized frequency bands,and the PSD was characterized in real-time by a low error rate,that is,5.2% from the Xz-axis direction of sand(42-43 kHz)and 5.6% from the XYz-axis of glass(30.9-33.9 kHz,46.2-47.2 kHz,38.3-41.3 kHz for each axis response).Therefore,this research complements the existing approaches for PsD characterization in particulate multiphase flow.

关键词： Solid particulate flow Triaxial vibration High-frequency response Particle wall Particle size distribution

Dual-functional POM@IL complex modulate hole transport layer properties and interfacial charge dynamics for highly efficient and stable perovskite solar cells

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Chinese Chemical Letters 2024年第7期35卷 461-464页

作者： Boyuan Hu Jian zhang Yulin Yang Yayu Dong jiaqi Wang Wei Wang Kaifeng Lin Debin Xia MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China

The severe interfacial charge recombination as well as the stability issues brought by the Li-TFSI still hinder the commercialization of high-performance perovskite solar cells(PSCs).Here,a polyoxometalates(POMs)-based complex,POM@ionic liquid(IL),is synthesized and applied as an effective additive that simultaneously enhances the performance and stability of *** interactions between POM@IL complex and Li-TFSI inhibit the aggregation of *** synergistic oxidation of POM@IL complex and Li-TFSI towards 2,2,7,7-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene(Spiro-OMeTAD)effectively enhances the electrical properties of hole transport layer film and the photovoltaic performances of *** champion device modified with the POM@IL complex yields an excellent power conversion efficiency(PCE)of 22.73%.Moreover,the incorporation of POM@IL improves the humidity stability of *** storing under high humidity conditions(25℃,60%RH)for 1200 h,the POM@IL modified device retained a remarkable 81.2%of its initial *** work provides new insight into constructing POMs-based materials for high-performance photovoltaic devices.

关键词： Polyoxometalates Ionic liquid Perovskite solar cells Energy alignment Humidity stability

The weakening effect of urbanization on tropical cyclone surface winds:An observational study for Shanghai

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Tropical Cyclone Research and Review 2024年第1期13卷 15-23页

作者： Lechuan zhang Hui Yu Xiangyu ao Shengming Tang Chinese Academy of Meteorological Sciences BeijingChina Shanghai Typhoon Institute China Meteorological AdministrationShanghaiChina

The observation-reanalysis difference method(OMR)and wind proﬁleﬁtting method were used to analyze the inﬂuence urbanization has on the near-surface wind speed in Shanghai during tropical cyclone *** data used include daily wind speed data from the Shanghai Meteorological Observatory Station collected from 1991 to 2020,hourly wind speed data from 100 m high wind towers from 2017 to 2019,and reanalysis data that covered the same *** results indicated that during tropical cyclone occurrence,the wind speed of the OMR in the central urban region was signiﬁcantly lower than that in the suburban area,and the OMR declined more obviously over the year,down to-8 m/s in *** leads to the increase of average wind weakening rate to be higher than the maximum wind weakening rate,causing the maximum weakening rate of the central urban region to the average wind over 80%,while maximum wind speed was less than 80%.The weakening rate of both the average and maximum wind speeds during tropical cyclone impacts is greater than the rate that the annual average wind speed was reduced.A logarithmic variation was visible in the wind proﬁle of the island station during tropical cyclone occurrence,with an average friction velocity U*of 0.9389 m/s and an average rough length z0 of 0.4915 *** wind speed during tropical cyclone events was higher than the three-year average wind speed within each *** suburban stations show a linear variation,and every hundred meters of height results in an increase of 5–6 m/s in the wind speed change *** 100 m of altitude,the wind speed in the suburban region is reduced by approximately 40%.

关键词： Urbanization Tropical cyclone Shanghai Wind speed

Protective effects of baffles with different positions,row spacings,heights on debris flow impact

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Journal of Mountain Science 2024年第7期21卷 2352-2367页

作者： SUN Xinpo CHEN Min BI Yuzhang zHENG Lu CHE Chi XU ao TIAN zijian JIANG zheyuan College of Civil Engineering Sichuan University of Science and EngineeringZigong 643000China College of Resources and Environment Fujian Agriculture and Forestry UniversityFuzhou 350002China School of Civil Engineering Fuzhou UniversityFuzhou 350108China Jiangsu Key Laboratory of Urban Underground Engineering&Environmental Safety Institute of Geotechnical EngineeringSoutheast UniversityNanjing 210096China Beijing Urban Construction Science Technology Promoting Association Beijing 100055China SUSE-Bz Geoenvironmental Engineering Joint Laboratory Sichuan University of Science and EngineeringZigong 643000China

The baffle effectively slowed down debris flow velocity,reduced its kinetic energy,and significantly shortened the distance of debris flow ***,they are widely used for protection against natural hazards such as landslides and *** study,based on the threedimensional DEM(Discrete Element Method),investigated the impact of different baffle positions on debris flow *** flow velocity and kinetic energy variations were studied through single-factor *** baffle positions were preliminarily selected by analyzing the influence of the first-row baffle position on the impact force and accumulation mass of debris ***,based on the selected baffle positions and four factors influencing the effectiveness of baffle protection(baffle position(P),baffle height(h),row spacing(S_(r)),and angle of transit area(α)),an orthogonal design was employed to further explore the optimal arrangement of *** research results indicate that the use of a baffle structure could effectively slow down the motion velocity of debris flows and dissipate their *** the baffle is placed in the transit area,the impact force on the first-row baffle is greater than that when the baffle is placed in the deposition ***,when the baffle is placed in the transit area,the obstruction effect on debris flow mass is also greater than that when the baffle is placed in the deposition *** orthogonal experimental range analysis,when the impact on the first row of baffles is used as the evaluation criterion,the importance of each influencing factor is ranked asα>P>S_(r)>*** the mass of debris flow behind the baffle is regarded as the evaluation criterion,the rank is changed to P>α>S_(r)>*** experimental simulation results show that the optimal baffle arrangement is:P_(5),S_(r)=16,α=35°,h=9.

关键词： Debris flow Baffle Protective effect Discrete element

Artificial visual-tactile perception array for enhanced memory and neuromorphic computations

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InfoMat 2024年第3期6卷 81-94页

作者： jiaqi He Ruilai Wei Shuaipeng Ge Wenqiang Wu Jianchao Guo Juan Tao Ru Wang Chunfeng Wang Caofeng Pan CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijingthe People's Republic of China School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijingthe People's Republic of China Guangdong Research Center for Interfacial Engineering of Functional Materials College of Materials Science and EngineeringShenzhen UniversityShenzhenthe People's Republic of China

The emulation of human multisensory functions to construct artificial perception systems is an intriguing challenge for developing humanoid robotics and cross-modal human–machine *** by human multisensory signal generation and neuroplasticity-based signal processing,here,an artificial perceptual neuro array with visual-tactile sensing,processing,learning,and memory is *** neuromorphic bimodal perception array compactly combines an artificial photoelectric synapse network and an integrated mechanoluminescent layer,endowing individual and synergistic plastic modulation of optical and mechanical information,including short-term memory,long-term memory,paired pulse facilitation,and“learning-experience”***tial or superimposed visual and tactile stimuli inputs can efficiently simulate the associative learning process of“Pavlov's dog”.The fusion of visual and tactile modulation enables enhanced memory of the stimulation image during the learning process.A machine-learning algorithm is coupled with an artificial neural network for pattern recognition,achieving a recognition accuracy of 70%for bimodal training,which is higher than that obtained by unimodal *** addition,the artificial perceptual neuron has a low energy consumption of~20 *** its mechanical compliance and simple architecture,the neuromorphic bimodal perception array has promising applications in largescale cross-modal interactions and high-throughput intelligent perceptions.

关键词： artificial intelligent systems mechanoluminescence neuromorphic computing optoelectronic synapse visual-tactile perception