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Micromechanism and mathematical model of stress sensitivity in tight reservoirs of binary granular medium

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Petroleum Science 2024年第3期21卷 1780-1795页

作者： Jian-Bang Wu Sheng-Lai yang Qiang Li Kun yang Can Huang Dao-Ping Lv wei Zhou State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China Laboratoire de G eologie Ecole Normale Sup erieure/CNRS UMR8538PSL Research UniversityParis75005France Research Institute of Exploration and Development Xinjiang Oilfield CompanyKaramay834000XinjiangChina

Research on reservoir rock stress sensitivity has traditionally focused on unary granular structures,neglecting the binary nature of real reservoirs,especially tight *** the stresssensitive behavior and mathematical characterization of binary granular media remains a challenging *** this study,we conducted online-NMR experiments to investigate the permeability and porosity evolution as well as stress-sensitive control mechanisms in tight sandy conglomerate *** results revealed stress sensitivity coefficients between 0.042 and 0.098 and permeability damage rates ranging from 65.6%to 90.9%,with an average pore compression coefficient of 0.0168—0.0208 MPa ***-scale compression occurred in three stages:filling,compression,and compaction,with matrix pores playing a dominant role in pore *** stress sensitivity of binary granular media was found to be influenced by the support structure and particle *** stress sensitivity was associated with small fine particle size,high fines content,high uniformity coefficient of particle size,high plastic deformation,and low Young's ***-supported samples exhibited a high irreversible permeability damage rate(average=74.2%)and stress sensitivity coefficients(average=0.089),with pore spaces more *** contrast,grain-supported samples showed low stress sensitivity coefficients(average=0.021)at high stress *** on the experiments,we developed a mathematical model for stress sensitivity in binary granular media,considering binary granular properties and nested interactions using Hertz contact deformation and Poiseuille *** describing the change in activity content of fines under stress,we characterized the non-stationary state of compressive deformation in the binary granular structure and classified the reservoir into three *** model was applied for production prediction using actual data from the Mahu reservoir in China,showing that the e

关键词： Stress sensitivity Binary granular medium Tight reservoir Online-NMR Reservoir energy retention rate

Noncovalent cross-linked engineering hydrogel with low hysteresis and high sensitivity for flexible self-powered electronics

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Journal of Energy Chemistry 2024年第7期94卷 136-147页

作者： Hang Yuan Shaowei Han Jia wei Songwei Li Peipei yang Hao-yang Mi Chuntai Liu Changyu Shen National Engineering Research Center for Advanced Polymer Processing Technology Key Laboratory of Materials Processing and Mold(Ministry of Education)Zhengzhou UniversityZhengzhou450002HenanChina Yunnan TobaccoQuality Inspection&Supervision Station Kunming 650106YunnanChina

In this study,the hydrogel network was reinforced by covalent-like hydrogen bonding,and the strong binding ability of boron-nitrogen coordination served as the main driving *** them,acrylamide(AM)and 3-acrylamidophenylboronic acid(AAPBA)were the main body,and the numerous hydroxyl groups in the trehalose(Treh)molecule and other polymer groups formed strong hydrogen bonding interactions to improve the mechanical properties of the PAM/PAAPBA/Treh(PAAT)hydrogel and ensured the simplicity of the synthesis *** hydrogel possessed high strain at break(1239%),stress(64.7 kPa),low hysteresis(100%to 500%strain,corresponding to dissipation energy from 1.37 to 7.80 kJ/m^(3)),and outstanding cycling stability(retained more than 90%of maximum stress after 200 ten-sile cycles).By integrating carbon nanotubes(CNTs)into PAAT hydrogel(PAATC),the PAATC hydrogel with excellent strain response performance was successfully *** PAATC conductive hydro-gel exhibited high sensitivity(gauge factor(GF)=10.58 and sensitivity(S)=0.304 kPa^(-1)),wide strain response range(0.5%-1000%),fast response time(450 ms),and short recovery time(350 ms),excellent fatigue resistance,and strain response ***,the PAATC-based triboelectric nanogener-ator(TENG)displayed outstanding energy harvesting performance,which shows its potential for appli-cation in self-powered electronic devices.

关键词： Low hysteresis Covalent-like hydrogen bonding Boron-nitrogen coordination Hydrogel sensor Triboelectric nanogenerator

Adhesion strength of tetrahydrofuran hydrates is dictated by substrate stiffness

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Petroleum Science 2024年第1期21卷 667-673页

作者： Yan-Wen Lin Tong Li Yi Zhang wei-wei Yan Xiao-Ming Chen Zhi-Sen Zhang Jian-yang Wu Department of Physics Research Institute for Biomimetics and Soft MatterJiujiang Research Institute and Fujian Provincial Key Laboratory for Soft Functional Materials ResearchXiamen UniversityXiamen361005FujianChina Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201ZhejiangChina Key Laboratory of Icing and Anti/De-icing China Aerodynamics Research and Development CenterMianyang621000SichuanChina Micro-and Nano-technology Research Center State Key Laboratory for Manufacturing Systems EngineeringXi’an Jiaotong UniversityXi’an710049ShaanxiChina Electronic Materials Research Lab Key Laboratory of the Ministry of EducationXi’an Jiaotong UniversityXi’an710049ShaanxiChina NTNU Nanomechanical Lab Norwegian University of Science and Technology(NTNU)Trondheim7491Norway

Understanding the hydrate adhesion is important to tackling hydrate accretion in ***,the relationship between the Tetrahydrofuran(THF)hydrate adhesion strength(AS)and surface stiffness on elastic coatings is systemically examined by experimental shear force measurements and theoretical *** mechanical factor-elastic modulus of the coatings greatly dictates the hydrate AS,which is explained by the adhesion mechanics theory,beyond the usual factors such as wettability and structural ***,the hydrate AS increases with reducing the thickness of the elastic coatings,resulted from the decrease of the apparent surface elastic *** effect of critical thickness for the elastic materials with variable elastic modulus on the hydrate AS is also *** study provides deep perspectives on the regulation of the hydrate AS by the elastic modulus of elastic materials,which is of significance to design anti-hydrate surfaces for mitigation of hydrate accretion in petro-pipelines.

关键词： Hydrate Adhesion strength Elastic modulus Coatings

Activation Redistribution Based Hybrid Asymmetric Quantization Method of Neural Networks

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工程与科学中的计算机建模(英文) 2024年第1期138卷 981-1000页

作者： Lu wei Zhong Ma Chaojie yang R&D Innovation Center Xi’an Microelectronics Technology InstituteXi’an710065China

The demand for adopting neural networks in resource-constrained embedded devices is continuously *** is one of the most promising solutions to reduce computational cost and memory storage on embedded *** order to reduce the complexity and overhead of deploying neural networks on Integeronly hardware,most current quantization methods use a symmetric quantization mapping strategy to quantize a floating-point neural network into an integer ***,although symmetric quantization has the advantage of easier implementation,it is sub-optimal for cases where the range could be skewed and not *** often comes at the cost of lower *** paper proposed an activation redistribution-based hybrid asymmetric quantizationmethod for neural *** proposedmethod takes data distribution into consideration and can resolve the contradiction between the quantization accuracy and the ease of implementation,balance the trade-off between clipping range and quantization resolution,and thus improve the accuracy of the quantized neural *** experimental results indicate that the accuracy of the proposed method is 2.02%and 5.52%higher than the traditional symmetric quantization method for classification and detection tasks,*** proposed method paves the way for computationally intensive neural network models to be deployed on devices with limited computing *** will be available on https://***/ycjcy/Hybrid-Asymmetric-Quantization.

关键词： Quantization neural network hybrid asymmetric accuracy

Research on wind turbine blade damage based on pre-stressed FBG strain sensors

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Optoelectronics Letters 2024年第2期20卷 83-88页

作者： CAI Yujie yang Zhiquan ZHANG Bihua wei Yufeng Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Faculty of Public Safety and Emergency Management Kunming University of Science and TechnologyKunming 650093China Beijing FBGTECH Optic Electric Technology Co. Ltd.Beijing 100043China1

One of the essential parts of a wind power generator that captures wind energy is the wind turbine *** safety of the blades rapidly declines as a wind turbine's operating period *** real-time monitoring,a chip-type pre-stressed fiber Bragg grating(FBG)strain sensor was *** sensor's structure was improved using simulation analysis along with *** was discovered through calibration trials that the pre-stressing method expanded the sensor's range of measurement,guaranteed overall linearity,and prevented the potential hysteresis phenomena during *** sensor's final sensitivity was calculated to be 1.970 pm/με,and its linear fitting coefficient was ***,the sensor was used to monitor the wind turbine blades and the strain change curve of the root of a normally functioning blade is found to be a sine curve,which provides a certain reference value for judging whether the blade is damaged in the future.

关键词： blade strain damage

Research on Distributed Coordination Control Method for Microgrid System Based on Finite-time Event-triggered Consensus Algorithm

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Chinese Journal of Electrical Engineering 2024年第2期10卷 103-115页

作者： Lizhen Wu Heng yang Jianping wei Wendong Jiang College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou 730050China National Active Distribution Network Technology Research Center Beijing Jiaotong UniversityBeijing 100044China

Microgrids are networked control systems with multiple distributed generators(DGs).Microgrids are associated with many problems,such as communication delays,high sampling rates,and frequent controller updates,which make it challenging to realize coordination control among the ***,finite-time consensus algorithms and event-triggered control methods are combined to propose a distributed coordination control method for microgrid *** DG in the microgrid system serves as an agent node in the control network,and a distributed secondary controller is designed using finite-time consensus algorithm,such that the frequency and voltage restoration control has a faster convergence time and better anti-interference *** event-triggered function was designed based on the state information of the *** controller exchanges the state information at the trigger *** stability is analyzed using the Lyapunov stability theory,and it is verified that the controller cannot exhibit the Zeno phenomenon in the event-triggered process.A simulation platform was developed in Matlab/Simulink to verify that the proposed control method can effectively reduce the frequency of controller updates during communication delays and the burden on the communication network.

关键词： Microgrid event-triggered control distributed secondary control finite-time consensus algorithm coordination control

Temperature prediction model in multiphase flow considering phase transition in the drilling operations

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Petroleum Science 2024年第3期21卷 1969-1979页

作者： yang Zhang Yong-An Li Xiang-wei Kong Hao Liu Teng-Fei Sun College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100027China School of Petroleum Engineering Yangtze UniversityWuhan430000HubeiChina

The study considers gas compression properties,gas slippage,back pressure(BP),phase transition(PT),well depth,and differences in gas-liquid physical properties.A new temperature model for multiphase flow is proposed by considering phase transition in the drilling *** mathematical model of multiphase flow is solved using the finite difference method with annulus mesh division for grid nodes,and a module for multiphase flow calculation and analysis is *** results indicate that the temperature varies along the annulus with the variation of gas influx at the bottom of the *** the process of controlled pressure drilling,as gas slips along the annulus to the wellhead,its volume continuously expands,leading to an increase in the gas content within the annulus,and consequently,an increase in the pressure drop caused by gas *** temperature increases with the increase in BP and decreases in gas influx rate and wellbore *** gas influx,the thermal conductivity coefficient for the gas-drilling mud two phases is significantly weakened,resulting in a considerable change in temperature along the *** the context of MPD,the method of slightly changing the temperature along the annulus by controlling the back pressure is feasible.

关键词： Managed pressure drilling Phase transition Temperature Gas-drilling mud two phase

Odorant-binding protein 19 in Monochamus alternatus involved in the recognition of a volatile strongly emitted from ovipositing host pines

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Insect Science 2024年第1期31卷 134-146页

作者： Ruinan yang Dongzhen Li Shancheng Yi Yi wei Manqun Wang Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina Key Laboratory of Forest Protection of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijingChina

Monochamus alternatus is the primary carrier of pine wood nematodes,which pose a serious threat to Pinus *** many *** emerging *** adults feed on heathy host pines,while matured adults transfer to stressed host pines for mating and *** odorant-binding proteins(OBPs)of *** have been proved to aid in the complex process of host *** clarify the corresponding relations between OBPs and pine volatiles,more OBPs need to be *** this research,MaltOBP19 showed a specific expression in the antennae and mouthparts of ***,and it was marked in 4 types of antenna sensilla by *** binding assays demonstrated the high binding affinity of MaltOBP19 with camphene and myrcene in *** Y-tube olfactory experiments,*** adults were attracted by camphene and RNAi of OBP19 via microinjection significantly decreased their attraction *** induced phobotaxis,but RNAi had no significant effect on this ***,we found that ingesting dsOBP19 produced by a bacteria-expressed system with a newly constructed vector could lead to the knockdown of *** results suggest that MaltOBP19 may play a role in the process of host conversion via the recognition of camphene,which has been identified to be strongly released in stressed host *** addition,it is proved that knockdown of OBP can be achieved by oral administration of bacteria-expressed double-stranded RNA in *** adults,providing a new perspective in the control of ***.

关键词： bacteria-expressed dsRNA camphene Japanese pine sawyer beetle MaltOBP19 RNAi stressed host pines

Vehicle Abnormal Behavior Detection Based on Dense Block and Soft Thresholding

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Computers, Materials & Continua 2024年第6期79卷 5051-5066页

作者： Yuanyao Lu wei Chen Zhanhe Yu Jingxuan Wang Chaochao yang School of Information Science and Technology North China University of TechnologyBeijing100144China School of Electrical and Control Engineering North China University of TechnologyBeijing100144China

With the rapid advancement of social economies,intelligent transportation systems are gaining increasing *** to these systems is the detection of abnormal vehicle behavior,which remains a critical challenge due to the complexity of urban roadways and the variability of external *** research on detecting abnormal traffic behaviors is still nascent,with significant room for improvement in recognition *** address this,this research has developed a new model for recognizing abnormal traffic *** model employs the R3D network as its core architecture,incorporating a dense block to facilitate feature *** approach not only enhances performance with fewer parameters and reduced computational demands but also allows for the acquisition of new features while simplifying the overall network ***,this research integrates a self-attentive method that dynamically adjusts to the prevailing traffic conditions,optimizing the relevance of features for the task at *** temporal analysis,a Bi-LSTM layer is utilized to extract and learn from time-based data *** research conducted a series of comparative experiments using the UCF-Crime dataset,achieving a notable accuracy of 89.30%on our test *** results demonstrate that our model not only operates with fewer parameters but also achieves superior recognition accuracy compared to previous models.

关键词： Vehicle abnormal behavior deep learning ResNet dense block soft thresholding