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Material-SAM:Adapting SAM for Material XCT

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Computers, Materials & Continua 2024年第3期78卷 3703-3720页

作者： Xuelong Wu Junsheng Wang Zhongyao Li Yisheng Miao Chengpeng Xue Yuling Lang Decai Kong Xiaoying Ma Haibao Qiao School of Materials Science and engineering Beijing Institute of TechnologyBeijing100081China Senior engineer at the Simulation Center Citic Dicastal Co.Ltd.Qinhuangdao066010China

X-ray Computed Tomography(XCT)enables non-destructive acquisition of the internal structure of materials,and image segmentation plays a crucial role in analyzing material XCT *** paper proposes an image segmentation method based on the Segment Anything model(SAM).We constructed a dataset of carbide in nickel-based single crystal superalloys XCT images and preprocessed the images using median filtering,histogram equalization,and gamma ***,SAM was fine-tuned to adapt to the task of material XCT image segmentation,resulting in *** compared the performance of threshold segmentation,SAM,U-Net model,and *** method achieved 88.45%Class Pixel Accuracy(CPA)and 88.77%Dice Similarity Coefficient(DSC)on the test set,outperforming SAM by 5.25%and 8.81%,respectively,and achieving the highest ***-SAM demonstrated lower input requirements compared to SAM,as it only required three reference points for completing the segmentation task,which is one-fifth of the requirement of ***-SAM exhibited promising results,highlighting its potential as a novel method for material XCT image segmentation.

关键词： Segment Anything model X-ray computed tomography U-Net Ni-based superalloys foundation models

A novel responsive stabilizing Janus nanosilica as a nanoplugging agent in water-based drilling fluids for exploiting hostile shale environments

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Petroleum Science 2024年第2期21卷 1190-1210页

作者： Alain Pierre Tchameni Lv-Yan Zhuo Lesly Dasilva Wandji Djouonkep Robert Dery Nagre Lu-Xin Chen Lin Zhao Chao Ma Bin-Qiang Xie College of Petroleum engineering Yangtze UniversityWuhan430100HubeiChina Key Laboratory of Drilling and Production engineering for Oil and Gas HubeiChina Lost Circulation Control Laboratory National Engineering Laboratory for Petroleum Drilling EngineeringYangtze UniversityWuhan430100HubeiChina College of Petroleum engineering Shandong Institute of Petroleum and Chemical TechnologyDongying257061ShandongChina Petroleum engineer Research institute of Petrochina Dagang Oilfield Tianjin300280China Department of Chemical engineering Kumasi Technical UniversityP.O.Box 854KumasiGhana

Thermo-responsive nanocomposites have recently emerged as potential nanoplugging agents for shale stabilization in high-temperature water-based drilling fluids(WBDFs). However, their inhibitory properties have not been very effective in high-temperature drilling operations. Thermo-responsive Janus nanocomposites are expected to strongly interact with clay particles from the inward hemisphere of nanomaterials, which drive the establishment of a tighter hydrophobic membrane over the shale surface at the outward hemisphere under geothermal conditions for shale stabilization. This work combines the synergistic benefits of thermo-responsive and zwitterionic nanomaterials to synchronously enhance the chemical inhibitions and plugging performances in shale under harsh conditions. A novel thermoresponsive Janus nanosilica(TRJS) exhibiting zwitterionic character was synthesized, characterized,and assessed as shale stabilizer for WBDFs at high temperatures. Compared to pristine nanosilica(Si NP)and symmetrical thermo-responsive nanosilica(TRS), TRJS exhibited anti-polyelectrolyte behaviour, in which electrolyte ions screened the electrostatic attraction between the charged particles, potentially stabilizing nanomaterial in hostile shaly environments(i.e., up to saturated brine or API brine). Macroscopically, TRJS exhibited higher chemical inhibition than Si NP and TRS in brine, prompting a better capability to control pressure penetration. TRJS adsorbed onto the clay surface via chemisorption and hydrogen bonding, and the interactions became substantial in brine, according to the results of electrophoretic mobility, surface wettability, and X-ray diffraction. Thus, contributing to the firm trapping of TRJS into the nanopore structure of the shale, triggering the formation of a tight hydrophobic membrane over the shale surface from the outward hemisphere. The addition of TRJS into WBDF had no deleterious effect on fluid properties after hot-treatment at 190℃, implying that TRJ

关键词： Janus nanosilica Thermo-responsive copolymer Anti-polyelectrolyte effect Shale stabilizer Inhibition Plugging Drilling fluid

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Impacts of Defoliation on Morphological Characteristics and Non-Structural Carbohydrates of Populus talassica × Populus euphratica Seedlings

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1689-1703页

作者： Mengxu Su Zhanjiang Han Zhen Zhao Xiaofeng Wu Jiaju Wu College of Life Science and Technology Tarim UniversityXinjiang Production and Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim BasinAlar843300China Agricultural Science Research institute of the First Division Xinjiang Production and Construction CorpsAlar843300China

Leaves are important‘source’organs that synthesize organic matter,providing carbon sources for plant ***,we used Populus talassica×Populus euphratica,the dominant species in ecological and timber forests,to simulate carbon limitation through artiﬁcial 25%,50%,and 75%defoliation treatments and explore the effects on root,stem,and leaf morphology,biomass accumulation,and carbon allocation *** the 60th d after treat-ment,under 25%defoliation treatment,the plant height,speciﬁc leaf weight,root surface area and volume,and concentrations of non-structural carbohydrates in stem and root were signiﬁcantly increased by 9.13%,20.00%,16.60%,31.95%,5.12%,and 9.34%,respectively,relative to the *** was no signiﬁcant change in the growth indicators under 50%defoliation treatment,but the concentrations of non-structural carbohydrates in the leaf and stem signiﬁcantly decreased,showing mostly a negative correlation between *** opposite was observed in the *** 75%defoliation treatment,the plant height,ground diameter,leaf number,single leaf area,root,stem,and total biomass were signiﬁcantly reduced by 14.15%,10.24%,14.86%,11.31%,11.56%,21.87%,and 16.82%,respectively,relative to the *** concentrations of non-structural carbohydrates in various organs were signiﬁcantly reduced,particularly in the consumption of the starch concentrations in the stem and *** results indicated that carbon allocation strategies can be adjusted to increase the con-centration of non-structural carbohydrates in root and meet plant growth needs under 25%and 50%***,75%defoliation signiﬁcantly limited the distribution of non-structural carbohydrates to roots and stems,reduced carbon storage,and thus inhibited plant ***-induced carbon limitation altered the carbon allocation pattern of ***×***,and the relationship between carbon reserves in roots and tree growth recovery after defoliation was *** study

关键词： Populus talassica×Populus euphratica defoliation carbon limitation carbon allocation non-structural carbohydrates

Calculation of Mass Concrete Temperature and Creep Stress under the Influence of Local Air Heat Transfer

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Computer Modeling in engineering & Sciences 2024年第9期140卷 2977-3000页

作者： Heng Zhang Chao Su Xiaohu Chen Zhizhong Song Weijie Zhan Academy of Science and Technology Changjiang Institute of Survey Planning Design and ResearchWuhan430010China College of Water Conservancy and Hydropower engineering Hohai UniversityNanjing210098China Chief engineer Office Wujiang Company of Goupitan Power Construction CooperationYuqing564408China

Temperature-induced cracking during the construction of mass concrete is a significant *** simulations of concrete temperature have primarily assumed that the concrete is placed in an open *** problem of heat transfer between the air and concrete has been simplified to the concrete’s heat dissipation ***,in the case of tubular concrete structures,where air inlet and outlet are relatively limited,the internal air temperature does not dissipate promptly to the external environment as it *** accurately simulate the temperature and creep stress in tubular concrete structures with enclosed air spaces during construction,we establish an air–concrete coupled heat transfer model according to the principles of conjugate heat transfer,and the accuracy of the model is verified through ***,we conduct a case study to analyze the impact of airflow within the ship lock corridor on concrete temperature and creep *** results demonstrate that enhancing airflow within the corridor can significantly reduce the maximum concrete *** with cases in which airflow within the corridor is neglected,the maximum concrete temperature and maximum tensile stress can be reduced by 12.5℃ and 0.7 MPa,respectively,under a wind speed of 4 m/*** results of the traditional calculation method are relatively close to those obtained at a wind speed of 1 m/***,the temperature reduction process in the traditional method is faster,and the method yields greater tensile stress values for the corridor location.

关键词： Conjugate heat transfer temperature field mass concrete creep stress

An improved pulse coupled neural networks model for semantic IoT

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Digital Communications and Networks 2024年第3期10卷 557-567页

作者： Rong Ma Zhen Zhang Yide Ma Xiping Hu Edith C.H.Ngai Victor C.M.Leung School of Information Science and engineering Lanzhou UniversityLanzhou 730000China School of Medical Technology Beijing Institute of TechnologyBeijing100081China Department of Electrical and Electronic engineer The University of Hong KongHong Kong 999077China College of Computer Science and Software engineering Shenzhen UniversityShenzhen 518060China Department of Electrical and Computer engineering the University of British ColumbiaVancouverBC V6T 1Z4Canada

In recent years,the Internet of Things(IoT)has gradually developed applications such as collecting sensory data and building intelligent services,which has led to an explosion in mobile data ***,with the rapid development of artificial intelligence,semantic communication has attracted great attention as a new communication ***,for IoT devices,however,processing image information efficiently in real time is an essential task for the rapid transmission of semantic *** the increase of model parameters in deep learning methods,the model inference time in sensor devices continues to *** contrast,the Pulse Coupled Neural Network(PCNN)has fewer parameters,making it more suitable for processing real-time scene tasks such as image segmentation,which lays the foundation for real-time,effective,and accurate image ***,the parameters of PCNN are determined by trial and error,which limits its *** overcome this limitation,an Improved Pulse Coupled Neural Networks(IPCNN)model is proposed in this *** IPCNN constructs the connection between the static properties of the input image and the dynamic properties of the neurons,and all its parameters are set adaptively,which avoids the inconvenience of manual setting in traditional methods and improves the adaptability of parameters to different types of *** segmentation results demonstrate the validity and efficiency of the proposed self-adaptive parameter setting method of IPCNN on the gray images and natural images from the Matlab and Berkeley Segmentation *** IPCNN method achieves a better segmentation result without training,providing a new solution for the real-time transmission of image semantic information.

关键词： Internet of things(IoT) Semantic information Real-time application Improved pulse coupled neural network Image segmentation

Active Magnetic Compensation Based on Parametric Resonance Magnetometer

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Journal of Shanghai Jiaotong university(Science) 2024年第2期29卷 280-289页

作者：郭阳李绍良黄艺明骆曼箬刘华 School of Electronic Information and Electrical engineering Shanghai Jiao Tong UniversityShanghai 200240China Shanghai institute of Spacefight Control Technology Shanghai Key Laboratory of Space Intelligent Control TechnologyShanghai Engineer Research Center of InertiaShanghai 201109China

Based on the parametric resonance magnetometer(PRM)theory,this paper establishes an experimen-tal system of *** experimental results are consistent with the theoretical predictions.A PRM has been developed with sensitivity of 0.5 pT/Hz^(1/2),which can detect the magnitude of residual magnetic field;furthermore,a proportion-integration-differentiation(PID)closed-loop magnetic compensation system of the residual magnetic field also has been *** with open-loop compensation,the PID closed-loop compensation reduces the average value of the residual magnetic field in the z-axis direction from 0.0244nT to-0.0023nT,and the mean-square error from 0.2083 nT to 0.0691 *** the same way,the average value of the residual magnetic field in the y-axis direction is reduced from 0.0816nT to-0.0042nT,and the mean-square error from 0.1316nT to 0.0461 *** magnitude of residual magnetic fields in both directions is decreased to the order of picotesla(pT).In addition,based on the signal waveforms of the magnetometer,a method of verifying the effect of magnetic compensation is proposed.

关键词： magnetometer parametric resonance nuclear magnetic resonance gyroscope magnetic compensa-tion proportion-integration-differentiation(PID)

Calculation of Mass Concrete Temperature Containing Cooling Water Pipe Based on Substructure and Iteration Algorithm

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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 813-826页

作者： Heng Zhang Chao Su Zhizhong Song Zhenzhong Shen Huiguang Lei Changjiang institute of Survey PlanningDesign and ResearchWuhan430010China College ofWater Conservancy and Hydropower engineering Hohai UniversityNanjing210098China Chief engineer Office Wujiang Company of Goupitan Power Construction CooperationYuqing564408China

Mathematical physics equations are often utilized to describe physical phenomena in various fields of science and *** such equation is the Fourier equation,which is a commonly used and effective method for evaluating the effectiveness of temperature control measures for mass *** important measure for temperature control in mass concrete is the use of cooling water ***,the mismatch of grids between large-scale concrete models and small-scale cooling pipe models can result in a significant waste of calculation time when using the finite element ***,the temperature of the water in the cooling pipe needs to be iteratively calculated during the thermal transfer *** substructure method can effectively solve this problem,and it has been validated by *** Abaqus/Python secondary development technology provides engineers with enough flexibility to combine the substructure method with an iteration algorithm,which enables the creation of a parametric modeling calculation for cooling water *** paper proposes such a method,which involves iterating the water pipe boundary and establishing the water pipe unit substructure to numerically simulate the concrete temperature field that contains a cooling water *** verify the feasibility and accuracy of the proposed method,two classic numerical examples were *** results showed that this method has good applicability in cooling pipe *** the value of the iteration parameterαis 0.4,the boundary temperature of the cooling water pipes can meet the accuracy requirements after 4∼5 iterations,effectively improving the computational ***,this approach provides a useful tool for engineers to analyze the temperature control measures accurately and efficiently for mass concrete,such as cooling water pipes,using Abaqus/Python secondary development.

关键词： Fourier equation cooling water pipe mass concrete iteration algorithm

Local environment regulation of transition metal dichalcogenide-based single-atom catalysts

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Rare Metals 2024年第9期43卷 4019-4037页

作者： Ming-Hui Li Jing Li Xiao-Yu Zheng Yao Zhou Advanced Research institute of Multidisciplinary Science andSchool of Chemistry and Chemical engineering Beijing Institute of Technology Laser Micro/Nano Fabrication Laboratory School of Mechanical Engineering Beijing Institute of Technology

Single-atom catalysts have risen significant attention in the realm of green electrocatalytic energy conversion to address energy and environmental sustainability challenges. Transition metal dichalcogenide（TMD）-based single-atom catalysts are considered highly effective in electrocatalysis due to the TMDs' notable specific surface area, tunable elemental species and efficient utilization of single atoms. In order to enhance electrocatalytic performance, it is imperative to elaborately engineer the local environment surrounding the active sites of single atoms within TMDs. In this review, we initially explore the effects of synthesis methods on single-atom active sites and the influence of loading of single atoms on catalytic performance for TMDs. The modulation strategies of the local environment surrounding single-atom sites in TMDs are elaborated, including substitution engineering,surface adsorption, vacancies, spatial confinement and dual-atom site strategies. For each modulation strategy, the effects of diverse local environments on various electrocatalytic applications are presented, such as the oxygen evolution reaction, oxygen reduction reaction, nitrogen reduction reaction, CO2reduction reaction and CO oxidation. Ultimately, this study presents a comprehensive overview of the challenges encountered and the potential directions for the advancement of single-atom catalysts based on TMDs in the realm of electrocatalysis.

关键词： Electrocatalysis

Glacier area change and its impact on runoff in the Manas River Basin,Northwest China from 2000 to 2020

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Journal of Arid Land 2024年第7期16卷 877-894页

作者： WANG Tongxia CHEN Fulong LONG Aihua ZHANG Zhengyong HE Chaofei LYU Tingbo LIU Bo HUANG Yanhao College of Water Conservancy&Architectural engineering Shihezi UniversityShihezi 832000China Key Laboratory of Cold and Arid Regions Eco-Hydraulic engineering of Xinjiang Production&Construction corps Shihezi 832000China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China College of Sciences Shihezi UniversityShihezi 832000China

Understanding the distribution and dynamics of glaciers is of great significance to the management and allocation of regional water resources and socio-economic development in arid regions of Northwest *** this study,based on 36 Landsat images,we extracted the glacier boundaries in the Manas River Basin,Northwest China from 2000 to 2020 using eCognition combined with band operation,GIS(geographic information system)spatial overlay techniques,and manual visual *** further analyzed the distribution and variation characteristics of glacier area,and simulated glacial runoff using a distributed degree-day model to explore the regulation of runoff *** results showed that glacier area in the Manas River Basin as a whole showed a downward trend over the past 21 a,with a decrease of 10.86%and an average change rate of–0.54%/*** the increase in glacier scale,the number of smaller glaciers decreased exponentially,and the number and area of larger glaciers were relatively *** area showed a normal distribution trend of increasing first and then decreasing with *** 97.92%of glaciers were distributed at 3700–4800 m,and 48.11%of glaciers were observed on the northern and northeastern *** retreat rate of glaciers was the fastest(68.82%)at elevations below 3800 *** was a clear rise in elevation at the end of *** at different slope directions showed a rapid melting trend from the western slope to the southern slope then to the northern *** runoff in the basin showed a fluctuating upward trend in the past 21 a,with an increase rate of 0.03×10^(8) m^(3)/*** average annual glacial runoff was 4.80×10^(8) m^(3),of which 33.31%was distributed in the ablation season(June–September).The average annual contribution rate of glacial meltwater to river runoff was 35.40%,and glacial runoff accounted for 45.37%of the total runoff during the ablation *** addition,precipitation and glacial runoff had comp

关键词： glacier area glacial runoff climate change glacier boundary extraction distributed degree-day model Manas River Basin

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