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Experimental investigation of dynamic characteristics of leaching tubing for solution mining of salt cavern carbon and energy storage

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Petroleum Science 2024年第4期21卷 2703-2722页

作者： yin-Ping li Xin-Bo Ge Xi-lin Shi Hong-ling ma State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences University of Chinese Academy of Sciences College of Energy and Mining Engineering Shandong University of Science and Technology State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology

Salt caverns are extensively utilized for storing various substances such as fossil energy, hydrogen,compressed air, nuclear waste, and industrial solid waste. In China, when the salt cavern is leached through single-well water solution mining with oil as a cushion, engineering challenges arise with the leaching tubing, leading to issues like damage and instability. These problems significantly hinder the progress of cavern construction and the control of cavern shape. The primary cause of this is the flowinduced vibration instability of leaching tubing within a confined space, which results in severe bending or damage to the tubing. This study presents a model experimental investigation on the dynamic characteristics of leaching tubing using a self-developed liquid-solid coupling physical model experiment apparatus. The experiment utilizes a silicone-rubber pipe(SRP) and a polycarbonate pipe(PCP) to examine the effects of various factors on the dynamic stability of cantilevered pipes conveying fluid. These factors include external space constraint, flexural rigidity, medium outside the pipe, overhanging length, and end conditions. The experiments reveal four dynamic response phenomena: water hammer, static buckling, chaotic motion, and flutter instability. The study further demonstrates that the length of the external space constraint has a direct impact on the flutter critical flow velocity of the cantilevered pipe conveying fluid. Additionally, the flutter critical flow velocity is influenced by the end conditions and different external media.

关键词： Salt cavern storage Solution mining Leaching tubing Experimental investigation Flutter instability

Quantification of the concrete freeze–thaw environment across the Qinghai–Tibet Plateau based on machine learning algorithms

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Journal of Mountain Science 2024年第1期21卷 322-334页

作者： QIN Yanhui ma Haoyuan ZHANG Lele yin Jinshuai ZHENG Xionghui li Shuo Department of Civil Engineering Qingdao University of TechnologyQingdao 266520China Department of Geography Qinghai Normal UniversityXining 810008China

The reasonable quantification of the concrete freezing environment on the Qinghai–Tibet Plateau(QTP) is the primary issue in frost resistant concrete design, which is one of the challenges that the QTP engineering managers should take into account. In this paper, we propose a more realistic method to calculate the number of concrete freeze–thaw cycles(NFTCs) on the QTP. The calculated results show that the NFTCs increase as the altitude of the meteorological station increases with the average NFTCs being 208.7. Four machine learning methods, i.e., the random forest(RF) model, generalized boosting method(GBM), generalized linear model(GLM), and generalized additive model(GAM), are used to fit the NFTCs. The root mean square error(RMSE) values of the RF, GBM, GLM, and GAM are 32.3, 4.3, 247.9, and 161.3, respectively. The R^(2) values of the RF, GBM, GLM, and GAM are 0.93, 0.99, 0.48, and 0.66, respectively. The GBM method performs the best compared to the other three methods, which was shown by the results of RMSE and R^(2) values. The quantitative results from the GBM method indicate that the lowest, medium, and highest NFTC values are distributed in the northern, central, and southern parts of the QTP, respectively. The annual NFTCs in the QTP region are mainly concentrated at 160 and above, and the average NFTCs is 200 across the QTP. Our results can provide scientific guidance and a theoretical basis for the freezing resistance design of concrete in various projects on the QTP.

关键词： Freeze–thaw cycles Quantification machine learning algorithms Qinghai–Tibet Plateau Concrete

The Anti-Penetration Performance and Mechanism of Metal materials:A Review

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Engineering 2024年第9期40卷 131-157页

作者： Jialin Chen Shutao li Shang ma Yeqing Chen yin liu Quanwei Tian Xiting Zhong Jiaxing Song State Key Laboratory of Target Vulnerability Assessment Beijing 100036China Institute of Defense Engineering Academy of Military SciencePLABeijing 100036China Xi’an Rare Metal materials Institute Co. Ltd.Xi’an 710016China

This article reviews the anti-penetration principles and strengthening mechanisms of metal materials,ranging from macroscopic failure modes to microscopic structural characteristics,and further summarizes the micro-macro correlation in the anti-penetration ***,it outlines the constitutive models and numerical simulation studies utilized in the field of impact and *** the macro perspective,nine frequent penetration failure modes of metal materials are summarized,with a focus on the analysis of the cratering,compression shear,penetration,and plugging stages of the penetration *** reasons for the formation of adiabatic shear bands(ASBs)in metal materials with different crystal structures are elaborated,and the formation mechanism of the equiaxed grains in the ASB is *** the strength and the toughness of metal materials are related to the materials’crystal structures and *** toughness is mainly influenced by the deformation mechanism,while the strength is explained by the strengthening ***,the mechanical properties of metal materials depend on their microstructures,which are subject to the manufacturing process and material *** numerical simulation,the advantages and disadvantages of different constitutive models and simulation methods are summarized based on the application characteristics of metal materials in high-speed penetration *** summary,this article provides a systematic overview of the macroscopic and microscopic characteristics of metal materials,along with their mechanisms and correlation during the anti-penetration and impact-resistance processes,thereby making an important contribution to the scientific understanding of anti-penetration performance and its optimization in metal materials.

关键词： Metal materials Failure model Adiabatic shear band Strengthening mechanisms Numerical simulation

Short-Term Prediction of Photovoltaic Power Based on DBSCAN-SVM Data Cleaning and PSO-LSTM Model

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Energy Engineering 2024年第10期121卷 3019-3035页

作者： Yujin liu Zhenkai Zhang li ma Yan Jia Weihua yin Zhifeng liu School of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot010051China Key Laboratory ofWind Energy and Solar Energy Utilization Technology Ministry of EducationHohhot010051China Production management Department Inner Mongolia Energy Power Generation Investment Group Co.Ltd.Hohhot010051China

Accurate short-termphotovoltaic(PV)power prediction helps to improve the economic efficiency of power stations and is of great significance to the arrangement of grid scheduling *** order to improve the accuracy of PV power prediction further,this paper proposes a data cleaning method combining density clustering and support vector *** constructs a short-termPVpower predictionmodel based on particle swarmoptimization(PSO)optimized Long Short-Term Memory(LSTM)***,the input features are determined using Pearson’s correlation *** feature information is clustered using density-based spatial clustering of applications withnoise(DBSCAN),and then,the data in each cluster is cleanedusing support vectormachines(SVM).Secondly,the PSO is used to optimize the hyperparameters of the LSTM network to obtain the optimal network ***,different power prediction models are established,and the PV power generation prediction results are *** results show that the data methods used are effective and that the PSO-LSTM power prediction model based on DBSCAN-SVM data cleaning outperforms existing typical methods,especially under non-sunny days,and that the model effectively improves the accuracy of short-term PV power prediction.

关键词： Photovoltaic power prediction LSTM network DBSCAN-SVM PSO deep learning

Dynamic modeling and RBF neural network compensation control for space flexible manipulator with an underactuated hand

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Chinese Journal of Aeronautics 2024年第3期37卷 417-439页

作者： Dongyang SHANG Xiaopeng li Meng yin Fanjie li School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

In space operation,flexible manipulators and gripper mechanisms have been widely used because of light weight and ***,the vibration caused by slender structures in manipulators and the parameter perturbation caused by the uncertainty derived from grasping mass variation cannot be *** existence of vibration and parameter perturbation makes the rotation control of flexible manipulators difficult,which seriously affects the operation accuracy of ***’s more,the complex dynamic coupling brings great challenges to the dynamics modeling and vibration *** solve this problem,this paper takes the space flexible manipulator with an underactuated hand(SFMUH)as the research *** dynamics model considering flexibility,multiple nonlinear elements and disturbance torque is established by the assumed modal method(AMM)and Hamilton’s principle.A dynamic modeling simplification method is proposed by analyzing the nonlinear ***’s more,a sliding mode control(SMC)method combined with the radial basis function(RBF)neural network compensation is ***,the control law is designed using a saturation function in the control method to weaken the chatter *** the help of neural networks to identify the uncertainty composition in the SFMUH,the tracking accuracy is *** results of ground control experiments verify the advantages of the control method for vibration suppression of the SFMUH.

关键词： Space flexible manipulator RBF neural network Underactuated hand Dynamic models Model simplification

cKBET:assessing goodness of batch effect correction for single-cell RNA-seq

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Frontiers of Computer Science 2024年第1期18卷 215-228页

作者： Yameng ZHAO yin GUO limin li School of mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China

Single-cell RNA sequencing reveals the gene structure and gene expression status of a single cell,which can reflect the heterogeneity between ***,batch effects caused by non-biological factors may hinder data integration and downstream *** the batch effect can be evaluated by visualizing the data,which actually is subjective and *** this work,we propose a quantitative method cKBET,which considers the batch and cell type information *** cKBET method accesses batch effects by comparing the global and local fraction of cells of different batches in different cell *** verify the performance of our cKBET method on simulated and real biological data *** experimental results show that our cKBET method is superior to existing methods in most *** general,our cKBET method can detect batch effect with either balanced or unbalanced cell types,and thus evaluate batch correction methods.

关键词： single-cell RNA-seq dataset b batch effect assessment cKBET method

VOC emitted by biopharmaceutical industries:Source profiles,health risks,and secondary pollution

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Journal of Environmental Sciences 2024年第1期135卷 570-584页

作者： Jiawei ma lin li State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China National Engineering Laboratory for VOCs Pollution Control material&Technology University of Chinese Academy of SciencesBeijing 101408China

The biopharmaceutical industry contributes substantially to volatile organic compounds(VOCs)emissions,causing growing concerns and social developmental *** study conducted an on-site investigation of the process-based emission of VOCs from three biopharmaceutical *** the workshops of the three enterprises,26 VOCs were detected,which could be sorted into 4 classes:hydrocarbons,aromatic hydrocarbons,oxygen-containing compounds,and nitrogen-containing *** were the main components of waste gases,accounting for 44.13%-77.85%of the overall ***-based source profiles were compiled for each process unit,with the fermentation and extraction units of tiamulin fumarate being the main source of VOC *** heptanone,vinyl acetate,diethylamine,propylene glycol methyl ether(PGME),and benzene were screened as priority pollutants through a fuzzy comprehensive evaluation *** level concentration simulation results of the Gauss plume diffusion model demonstrated that the diffusivity of VOCs in the atmosphere was relatively high,indicating potential non-carcinogenic and carcinogenic risks 1.5-2 km ***,the process-based formation potentials of ozone and secondary organic aerosols(SOAs)were determined and indicated that N-methyl-2-pyrrolidone,dimethyl heptanone,and PGME should be preferentially controlled to reduce the ozone formation potential,whereas the control of benzene and chlorobenzene should be prioritized to reduce the generation of *** results provide a basis for understanding the characteristics of VOC emission by biopharmaceutical industries and their diffusion,potentially allowing the development of measures to reduce health risks and secondary pollution.

关键词： Biopharmaceutical Volatile organic compound Priority pollutant Exposure risk Secondary pollution

On the Security of Homomorphic Encryption Schemes with Restricted Decryption Oracles

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Journal of Systems Science & Complexity 2024年第5期37卷 2240-2261页

作者： ma Guangsheng li Hongbo School of mathematics and Physics North China Electric Power UniversityBeijing 100096China Academy of mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Fully homomorphic encryption(FHE)can be used for privacy-preserving aggregation of medical *** this typical application,the security against passive attacks has been well studied by li and Micciancio(2021).In this paper,the authors further consider a“nearly passive”kind of attack,where the attacker may behave like a passive attacker in the view of the third-party *** capture the security against this hard-to-detect attack,the authors propose a new notion of IND-CPA^(rD)*** authors show that the standard LWE encryption and its related FHE schemes can not defend against IND-CPA^(rD)attack,even under a stricter rule limiting the content and number of queries made by the *** make the application of FHE schemes more secure,the authors discuss some possible modifications that may serve as countermeasures to IND-CPA^(rD)attack.

关键词： Homomorphic encryption privacy secure cloud computing security

Transcranial magneto-Acoustic Stimulation Attenuates Synaptic Plasticity Impairment through the Activation of Piezo1 in Alzheimer’s Disease Mouse Model

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Research 2024年第1期2023卷 81-95页

作者： Fangxuan Chu Ruxin Tan Xin Wang Xiaoqing Zhou Ren ma Xiaoxu ma.ying li Ruixu liu Chunlan Zhang Xu liu Tao yin Zhipeng liu Institute of Biomedical Engineering Chinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin300192China Tianjin Institutes of Health Science Tianjin301600China Neuroscience Center Chinese Academy of Medical Science&Peking Union Medical CollegeBeijing100730China

The neuropathological features of Alzheimer’s disease include amyloid *** emerging evidence suggests that Piezo1,a mechanosensitive cation channel,plays a critical role in transforming ultrasound-related mechanical stimuli through its trimeric propeller-like structure,but the importance of Piezo1-mediated mechanotransduction in brain functions is less ***,apart from mechanical stimulation,Piezo1 channels are strongly modulated by *** assume that Piezo1 may play a role in converting mechanical and electrical signals,which could induce the phagocytosis and degradation of Aβ,and the combined effect of mechanical and electrical stimulation is superior to single mechanical ***,we design a transcranial magneto-acoustic stimulation(TmaS)system,based on transcranial ultrasound stimulation(TUS)within a magnetic field that combines a magnetoacoustic coupling effect electric field and the mechanical force of ultrasound,and applied it to test the above hypothesis in 5xFAD *** tests,in vivo electrophysiological recordings,Golgi–Cox staining,enzyme-linked immunosorbent assay,immunofluorescence,immunohistochemistry,real-time quantitative PCR,Western blotting,RNA sequencing,and cerebral blood flow monitoring were used to assess whether TmaS can alleviate the symptoms of AD mouse model by activating Piezo1.

关键词： stimulation Alzheimer Piezo1