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AHermitian C^(2) Differential Reproducing Kernel Interpolation Meshless Method for the 3D Microstructure-Dependent Static Flexural Analysis of Simply Supported and Functionally Graded Microplates
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作者 Chih-Ping Wu Ruei-Syuan Chang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期917-949,共33页
This work develops a Hermitian C^(2) differential reproducing kernel interpolation meshless(DRKIM)method within the consistent couple stress theory(CCST)framework to study the three-dimensional(3D)microstructuredepend... This work develops a Hermitian C^(2) differential reproducing kernel interpolation meshless(DRKIM)method within the consistent couple stress theory(CCST)framework to study the three-dimensional(3D)microstructuredependent static flexural behavior of a functionally graded(FG)microplate subjected to mechanical loads and placed under full simple supports.In the formulation,we select the transverse stress and displacement components and their first-and second-order derivatives as primary variables.Then,we set up the differential reproducing conditions(DRCs)to obtain the shape functions of the Hermitian C^(2) differential reproducing kernel(DRK)interpolant’s derivatives without using direct differentiation.The interpolant’s shape function is combined with a primitive function that possesses Kronecker delta properties and an enrichment function that constituents DRCs.As a result,the primary variables and their first-and second-order derivatives satisfy the nodal interpolation properties.Subsequently,incorporating ourHermitianC^(2)DRKinterpolant intothe strong formof the3DCCST,we develop a DRKIM method to analyze the FG microplate’s 3D microstructure-dependent static flexural behavior.The Hermitian C^(2) DRKIM method is confirmed to be accurate and fast in its convergence rate by comparing the solutions it produces with the relevant 3D solutions available in the literature.Finally,the impact of essential factors on the transverse stresses,in-plane stresses,displacements,and couple stresses that are induced in the loaded microplate is examined.These factors include the length-to-thickness ratio,the material length-scale parameter,and the inhomogeneity index,which appear to be significant. 展开更多
关键词 Consistent/modified couple stress theory differential reproducing kernel methods microplates point collocation methods static flexural 3d microstructure-dependent analysis
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Cookie Baking Process Optimization and Quality Analysis Based on Food 3D Printing
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作者 Liu Chenghai Li Jingyi +2 位作者 Wu Chunsheng Zhao Xinglong Zheng Xianzhe 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期61-73,共13页
In order to obtain better quality cookies, food 3D printing technology was employed to prepare cookies. The texture, color, deformation, moisture content, and temperature of the cookie as evaluation indicators, the in... In order to obtain better quality cookies, food 3D printing technology was employed to prepare cookies. The texture, color, deformation, moisture content, and temperature of the cookie as evaluation indicators, the influences of baking process parameters, such as baking time, surface heating temperature and bottom heating temperature, on the quality of the cookie were studied to optimize the baking process parameters. The results showed that the baking process parameters had obvious effects on the texture, color, deformation, moisture content, and temperature of the cookie. All of the roasting surface heating temperature, bottom heating temperature and baking time had positive influences on the hardness, crunchiness, crispiness, and the total color difference(ΔE) of the cookie. When the heating temperatures of the surfac and bottom increased, the diameter and thickness deformation rate of the cookie increased. However,with the extension of baking time, the diameter and thickness deformation rate of the cookie first increased and then decreased. With the surface heating temperature of 180 ℃, the bottom heating temperature of 150 ℃, and baking time of 15 min, the cookie was crisp and moderate with moderate deformation and uniform color. There was no burnt phenomenon with the desired quality. Research results provided a theoretical basis for cookie manufactory based on food 3D printing technology. 展开更多
关键词 food 3d printing baking process COOKIE quality analysis optimization of process parameter
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Simulation Analysis of Extrusion Process of Equilateral L-shaped Aluminum Profiles Based on Deform-3D
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作者 Guangchen XU Wenwu ZHANG +1 位作者 Sisi CHEN Mantong WANG 《Mechanical Engineering Science》 2023年第1期12-15,I0005,共5页
The extrusion deformation process of L-shaped aluminum profiles was numerically simulated using the finite element program Deform-3D.The simulation findings revealed that the deformation of the profiles was mostly cau... The extrusion deformation process of L-shaped aluminum profiles was numerically simulated using the finite element program Deform-3D.The simulation findings revealed that the deformation of the profiles was mostly caused by unequal material flow velocity,which resulted in the profiles bending.Determine the impact of extrusion parameters on the bending deformation of the profile after studying various parameters that may affect the material flow mode(hole position,extrusion speed). 展开更多
关键词 deform-3d extrusion processing BENdING
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A novel box-counting method for quantitative fractal analysis of threedimensional pore characteristics in sandstone
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作者 Huiqing Liu Heping Xie +2 位作者 Fei Wu Cunbao Li Renbo Gao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期479-489,共11页
Fractal theory offers a powerful tool for the precise description and quantification of the complex pore structures in reservoir rocks,crucial for understanding the storage and migration characteristics of media withi... Fractal theory offers a powerful tool for the precise description and quantification of the complex pore structures in reservoir rocks,crucial for understanding the storage and migration characteristics of media within these rocks.Faced with the challenge of calculating the three-dimensional fractal dimensions of rock porosity,this study proposes an innovative computational process that directly calculates the three-dimensional fractal dimensions from a geometric perspective.By employing a composite denoising approach that integrates Fourier transform(FT)and wavelet transform(WT),coupled with multimodal pore extraction techniques such as threshold segmentation,top-hat transformation,and membrane enhancement,we successfully crafted accurate digital rock models.The improved box-counting method was then applied to analyze the voxel data of these digital rocks,accurately calculating the fractal dimensions of the rock pore distribution.Further numerical simulations of permeability experiments were conducted to explore the physical correlations between the rock pore fractal dimensions,porosity,and absolute permeability.The results reveal that rocks with higher fractal dimensions exhibit more complex pore connectivity pathways and a wider,more uneven pore distribution,suggesting that the ideal rock samples should possess lower fractal dimensions and higher effective porosity rates to achieve optimal fluid transmission properties.The methodology and conclusions of this study provide new tools and insights for the quantitative analysis of complex pores in rocks and contribute to the exploration of the fractal transport properties of media within rocks. 展开更多
关键词 3d fractal analysis Fractal dimension Rock pore structure Box-counting method Permeability simulation Computational geosciences
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The Clinical Value of Ultrasound Image Texture Analysis in the Diagnosis of Uterine Adhesions
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作者 Meng Li Chanyu Zhang 《Open Journal of Obstetrics and Gynecology》 2024年第2期312-320,共9页
Purpose: This review examines the diagnostic value of transvaginal 3D ultrasound image texture analysis for the diagnosis of uterine adhesions. Materials and Methods: The total clinical data of 53 patients with uterin... Purpose: This review examines the diagnostic value of transvaginal 3D ultrasound image texture analysis for the diagnosis of uterine adhesions. Materials and Methods: The total clinical data of 53 patients with uterine adhesions diagnosed by hysteroscopy and the imaging data of transvaginal three-dimensional ultrasound from the Second Affiliated Hospital of Chongqing Medical University from June 2022 to August 2023 were retrospectively analysed. Based on hysteroscopic surgical records, patients were divided into two independent groups: normal endometrium and uterine adhesion sites. The samples were divided into a training set and a test set, and the transvaginal 3D ultrasound was used to outline the region of interest (ROI) and extract texture features for normal endometrium and uterine adhesions based on hysteroscopic surgical recordings, the training set data were feature screened and modelled using lasso regression and cross-validation, and the diagnostic efficacy of the model was assessed by applying the subjects’ operating characteristic (ROC) curves. Results: For each group, 290 texture feature parameters were extracted and three higher values were screened out, and the area under the curve of the constructed ultrasonographic scoring model was 0.658 and 0.720 in the training and test sets, respectively. Conclusion Relative clinical value of transvaginal three-dimensional ultrasound image texture analysis for the diagnosis of uterine adhesions. 展开更多
关键词 Transvaginal 3d Ultrasound Intrauterine Adhesion Texture analysis
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基于DEFORM-3D的新能源汽车电机定子冲裁成形有限元分析
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作者 佘冉 文少波 肖庆朋 《机械研究与应用》 2024年第4期133-137,共5页
电机作为新能源汽车的重要组成部件之一,其能量受到广泛的关注。而定子加工质量直接影响到电机的品质,进而影响到新能源汽车的性能。文章以新能源汽车电机高硅钢材料定子为研究对象,在SolidWorks软件中建立模型,运用DEFORM-3D软件对定... 电机作为新能源汽车的重要组成部件之一,其能量受到广泛的关注。而定子加工质量直接影响到电机的品质,进而影响到新能源汽车的性能。文章以新能源汽车电机高硅钢材料定子为研究对象,在SolidWorks软件中建立模型,运用DEFORM-3D软件对定子冲裁过程进行仿真模拟,通过改变冲裁间隙和冲裁速度,分析了冲裁过程中定子应力、应变和材料内部流动速率的变化规律。研究表明,随着冲裁间隙增大,最大冲裁力逐渐减小,且断裂成形存在滞后性;随着冲裁速度的增大,毛刺高度有所增加。研究结果为进一步优化定子冲裁工艺提供了依据,对定子生产制造具有一定指导意义。 展开更多
关键词 电机定子 冲裁 deform-3d 有限元分析 断面质量
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A Building Information Modeling-Life Cycle Cost Analysis Integrated Model to Enhance Decisions Related to the Selection of Construction Methods at the Conceptual Design Stage of Buildings
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作者 Nkechi McNeil-Ayuk Ahmad Jrade 《Open Journal of Civil Engineering》 2024年第3期277-304,共28页
Life Cycle Cost Analysis (LCCA) provides a systematic approach to assess the total cost associated with owning, operating, and maintaining assets throughout their entire life. BIM empowers architects and designers to ... Life Cycle Cost Analysis (LCCA) provides a systematic approach to assess the total cost associated with owning, operating, and maintaining assets throughout their entire life. BIM empowers architects and designers to perform real-time evaluations to explore various design options. However, when integrated with LCCA, BIM provides a comprehensive economic perspective that helps stakeholders understand the long-term financial implications of design decisions. This study presents a methodology for developing a model that seamlessly integrates BIM and LCCA during the conceptual design stage of buildings. This integration allows for a comprehensive evaluation and analysis of the design process, ensuring that the development aligns with the principles of low carbon emissions by employing modular construction, 3D concrete printing methods, and different building design alternatives. The model considers the initial construction costs in addition to all the long-term operational, maintenance, and salvage values. It combines various tools and data through different modules, including energy analysis, Life Cycle Assessment (LCA), and Life Cycle Cost Analysis (LCCA) to execute a comprehensive assessment of the financial implications of a specific design option throughout the lifecycle of building projects. The development of the said model and its implementation involves the creation of a new plug-in for the BIM tool (i.e., Autodesk Revit) to enhance its functionalities and capabilities in forecasting the life-cycle costs of buildings in addition to generating associated cash flows, creating scenarios, and sensitivity analyses in an automatic manner. This model empowers designers to evaluate and justify their initial investments while designing and selecting potential construction methods for buildings, and enabling stakeholders to make informed decisions by assessing different design alternatives based on long-term financial considerations during the early stages of design. 展开更多
关键词 Life Cycle Cost analysis (LCCA) Building Information Modeling (BIM) Cost decision Modular Construction and 3d Concrete Printing
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Multivariate adaptive regression splines analysis for 3D slope stability in anisotropic and heterogenous clay 被引量:1
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作者 Jim Shiau Van Qui Lai Suraparb Keawsawasvong 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期1052-1064,共13页
Little research can be found in relation to the stability of anisotropic and heterogenous soils in three dimensions.In this paper,we propose a study on the three-dimensional(3D)undrained slopes in anisotropic and hete... Little research can be found in relation to the stability of anisotropic and heterogenous soils in three dimensions.In this paper,we propose a study on the three-dimensional(3D)undrained slopes in anisotropic and heterogenous clay using advanced upper and lower bounds finite element limit analysis(FELA).The obtained stability solutions are normalized,and presented by a stability number that is a function of three geometrical ratios and two material ratios,i.e.depth ratio,length ratio,slope angle,shear strength gradient ratio and anisotropic strength ratio.Numerical results are compared with experimental data in the literature,and charts are presented to cover a wide range of design parameters.Using the multivariate adaptive regression splines(MARS)analysis,the respective influence and sensitivity of each design parameter on the stability number and the failure mechanism are investigated.An empirical equation is also developed to effectively estimate the stability number. 展开更多
关键词 3d undrained slope Limit analysis ANISOTROPY HETEROGENEITY
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The Deformation Analysis of the 3D Alignment Control Network Based on the Multiple Congruence Models
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作者 Xudong ZHANG Wenjun CHEN +5 位作者 Xiaodong ZHANG Yajun ZHENG Bin ZHANG Shaoming WANG Jiandong YUAN Guozhen SUN 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第2期21-31,共11页
In the construction and maintenance of particle accelerators,all the accelerator elements should be installed in the same coordinate system,only in this way could the devices in the actual world be consistent with the... In the construction and maintenance of particle accelerators,all the accelerator elements should be installed in the same coordinate system,only in this way could the devices in the actual world be consistent with the design drawings.However,with the occurrence of the movements of the reinforced concrete cover plates at short notice or building deformations in the long term,the control points upon the engineering structure will be displaced,and the fitness between the subnetwork and the global control network may be irresponsible.Therefore,it is necessary to evaluate the deformations of the 3D alignment control network.Different from the extant investigations,in this paper,to characterize the deformations of the control network,all of the congruent models between the points measured in different epochs have been identified,and the congruence model with the most control points is considered as the primary or fundamental model,the remaining models are recognized as the additional ones.Furthermore,the discrepancies between the primary S-transformation parameters and the additional S-transformation parameters can reflect the relative movements of the additional congruence models.Both the iterative GCT method and the iterative combinatorial theory are proposed to detect multiple congruence models in the control network.Considering the actual work of the alignment,it is essential to identify the competitive models in the monitoring network,which can provide us a hint that,even the fitness between the subnetwork and the global control network is good,there are still deformations which may be ignored.The numerical experiments show that the suggested approaches can describe the deformation of the 3D alignment control network roundly. 展开更多
关键词 similarity transformation 3d alignment control network deformation analysis hypothesis testing iterative global congruence test iterative combinatorial theory
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基于DEFORM-3D的直齿锥齿轮温闭塞锻造成形工艺探究
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作者 尹甜甜 《开封大学学报》 2023年第1期67-70,共4页
基于Deform-3D软件,利用正交实验,确定了汽车差速器直齿锥齿轮温闭塞锻造的最优工艺参数组合,并在该条件下进行了数值模拟,对模具的行程—载荷曲线、速度场、应力场以及应变场等进行了分析研究。通过实际工艺试验,对数值模拟进行了验证... 基于Deform-3D软件,利用正交实验,确定了汽车差速器直齿锥齿轮温闭塞锻造的最优工艺参数组合,并在该条件下进行了数值模拟,对模具的行程—载荷曲线、速度场、应力场以及应变场等进行了分析研究。通过实际工艺试验,对数值模拟进行了验证,从而为直齿锥齿轮温闭塞锻造工艺的实用化提供了一定的理论依据。 展开更多
关键词 deform-3d 直齿锥齿轮 温闭塞锻造
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3D characterization and analysis of pore structure of packed ore particle beds based on computed tomography images 被引量:12
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作者 杨保华 吴爱祥 +1 位作者 缪秀秀 刘金枝 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期833-838,共6页
Methods and procedures of three-dimensional (3D) characterization of the pore structure features in the packed ore particle bed are focused. X-ray computed tomography was applied to deriving the cross-sectional imag... Methods and procedures of three-dimensional (3D) characterization of the pore structure features in the packed ore particle bed are focused. X-ray computed tomography was applied to deriving the cross-sectional images of specimens with single particle size of 1-2, 2-3, 3-4, 4-5, 5-6, 6-7, 7-8, 8-9, 9-10 ram. Based on the in-house developed 3D image analysis programs using Matlab, the volume porosity, pore size distribution and degree of connectivity were calculated and analyzed in detail. The results indicate that the volume porosity, the mean diameter of pores and the effective pore size (d50) increase with the increasing of particle size. Lognormal distribution or Gauss distribution is mostly suitable to model the pore size distribution. The degree of connectivity investigated on the basis of cluster-labeling algorithm also increases with increasing the particle size approximately. 展开更多
关键词 packed ore particle bed 3d pore structure X-ray computed tomography image analysis
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On the global smooth solutions of 3D incompressible Hall-MHD equations
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作者 YUE Gao-cheng SUN Wen-da 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期319-327,共9页
The present paper is devoted to the well-posedness issue for the 3D incompressible Hall-MHD system obtained from kinetic models. Our analysis strongly relies on the use of the Fourier analysis. We establish the global... The present paper is devoted to the well-posedness issue for the 3D incompressible Hall-MHD system obtained from kinetic models. Our analysis strongly relies on the use of the Fourier analysis. We establish the global existence of smooth solutions for a class of large initial data, this result implies the initial velocity and magnetic field can be arbitrarily large. 展开更多
关键词 3d Hall-MHd WELL-POSEdNESS Fourier analysis
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Genetic Variation Analysis of 3D Gene and Molecular Detection of Porcine Kobuvirus in 2013-2014
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作者 倪艳秀 何孔旺 +10 位作者 茅爱华 俞正玉 李彬 郭容利 吕立新 祝昊丹 周俊明 温立斌 张雪寒 王小敏 汪伟 《Agricultural Science & Technology》 CAS 2015年第3期442-446,共5页
[Objective] This study aimed to investigate the prevalence and variation of porcine kobuvirus (PKV) in suckling piglets in China. [Method] In 2013-2014, 224 feces samples from suckling piglets with diarrhea in 27 pi... [Objective] This study aimed to investigate the prevalence and variation of porcine kobuvirus (PKV) in suckling piglets in China. [Method] In 2013-2014, 224 feces samples from suckling piglets with diarrhea in 27 pig farms of five provinces in China were collected to detect 3D genes of PKV with RT-PCR method; the sequences and genetic variation of 29 PKV 3D genes were analyzed. [Result] Total positive rate of PKV in feces samples from suckling piglets with diarrhea was 65.18% (146/224); total positive rate of PKV in pig farms was 85,2% (23/27); nucleotide sequences and the deduced amino acid sequences of 29 PKV 3D genes shared 87.0%-100% and 92.7%-100% homologies with six PKV-related 3D sequences, respectively. [Conclusion] PKV infection is prevalent in suckling piglets in China; PKV 3D genes exhibit high diversity. 展开更多
关键词 Porcine kobuvirus Molecular detection 3d gene Genetic variation analysis
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Method of fabricating artificial rock specimens based on extrusion free forming(EFF)3D printing
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作者 Xiaomeng Shi Tingbang Deng +2 位作者 Sen Lin Chunjiang Zou Baoguo Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1455-1466,共12页
Three-dimensional(3D)printing technology has been widely used to create artificial rock samples in rock mechanics.While 3D printing can create complex fractures,the material still lacks sufficient similarity to natura... Three-dimensional(3D)printing technology has been widely used to create artificial rock samples in rock mechanics.While 3D printing can create complex fractures,the material still lacks sufficient similarity to natural rock.Extrusion free forming(EFF)is a 3D printing technique that uses clay as the printing material and cures the specimens through high-temperature sintering.In this study,we attempted to use the EFF technology to fabricate artificial rock specimens.The results show the physico-mechanical properties of the specimens are significantly affected by the sintering temperature,while the nozzle diameter and layer thickness also have a certain impact.The specimens are primarily composed of SiO_(2),with mineral compositions similar to that of natural rocks.The density,uniaxial compressive strength(UCS),elastic modulus,and tensile strength of the printed specimens fall in the range of 1.65–2.54 g/cm3,16.46–50.49 MPa,2.17–13.35 GPa,and 0.82–17.18 MPa,respectively.It is capable of simulating different types of rocks,especially mudstone,sandstone,limestone,and gneiss.However,the simulation of hard rocks with UCS exceeding 50 MPa still requires validation. 展开更多
关键词 Artificial rock 3d printing Extrusion free forming(EFF) Similarity analysis Mechanical properties
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Biomechanical analysis of an absorbable material for treating fractures of the inferior orbital wall
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作者 Jin-Hai Yu Ze-Xi Sang +4 位作者 Huang Zhang Qi-Hua Xu Qin Huang Hong-Fei Liao Yao-Hua Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第7期1331-1336,共6页
AIM:To investigate the biomechanical properties and practical application of absorbable materials in orbital fracture repair.METHODS:The three-dimensional(3D)model of orbital blowout fractures was reconstructed using ... AIM:To investigate the biomechanical properties and practical application of absorbable materials in orbital fracture repair.METHODS:The three-dimensional(3D)model of orbital blowout fractures was reconstructed using Mimics21.0 software.The repair guide plate model for inferior orbital wall fracture was designed using 3-matic13.0 and Geomagic wrap 21.0 software.The finite element model of orbital blowout fracture and absorbable repair plate was established using 3-matic13.0 and ANSYS Workbench 21.0 software.The mechanical response of absorbable plates,with thicknesses of 0.6 and 1.2 mm,was modeled after their placement in the orbit.Two patients with inferior orbital wall fractures volunteered to receive single-layer and double-layer absorbable plates combined with 3D printing technology to facilitate surgical treatment of orbital wall fractures.RESULTS:The finite element models of orbital blowout fracture and absorbable plate were successfully established.Finite element analysis(FEA)showed that when the Young’s modulus of the absorbable plate decreases to 3.15 MPa,the repair material with a thickness of 0.6 mm was influenced by the gravitational forces of the orbital contents,resulting in a maximum total deformation of approximately 3.3 mm.Conversely,when the absorbable plate was 1.2 mm thick,the overall maximum total deformation was around 0.4 mm.The half-year follow-up results of the clinical cases confirmed that the absorbable plate with a thickness of 1.2 mm had smaller maximum total deformation and better clinical efficacy.CONCLUSION:The biomechanical analysis observations in this study are largely consistent with the clinical situation.The use of double-layer absorbable plates in conjunction with 3D printing technology is recommended to support surgical treatment of infraorbital wall blowout fractures. 展开更多
关键词 orbital blowout fracture absorbable material finite element analysis 3d printing technology
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基于DEFORM-3D轴向振动钻削304不锈钢有限元仿真
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作者 吕康 付朝霞 +3 位作者 陈伟 胡建 刘书明 王晓宇 《制造技术与机床》 北大核心 2023年第5期64-68,共5页
难加工材料微小孔钻削过程中存在钻削力大、断屑难及钻削温度高等加工问题,而轴向振动钻削方法可以解决此类问题。基于轴向振动钻削机理,对轴向振动钻削的运动特性和变厚切削特性进行了分析。通过DEFORM-3D软件建立了轴向振动钻削有限... 难加工材料微小孔钻削过程中存在钻削力大、断屑难及钻削温度高等加工问题,而轴向振动钻削方法可以解决此类问题。基于轴向振动钻削机理,对轴向振动钻削的运动特性和变厚切削特性进行了分析。通过DEFORM-3D软件建立了轴向振动钻削有限元模型,对304不锈钢进行了振动频率为550 Hz,振幅为16μm,转速为3000 r/min,进给量为50μm/r的轴向振动钻削和普通钻削仿真试验,对比分析了两种加工过程中的切屑形态、轴向力和扭矩等。结果表明:与普通钻削相比,轴向振动钻削具有更好的断屑效果,可以降低平均轴向力约48.1%,降低平均扭矩约38.2%。 展开更多
关键词 振动钻削 不锈钢 deform-3d 钻削力
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Dynamic response analysis of liquefiable ground due to sinusoidal waves of different frequencies of shield construction
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作者 Wang Jingyue Ge Xinsheng +4 位作者 Sun Jingyuan Liu Yasheng Shang Zhuo Wang Zhiqiang Tian Maoguo 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第3期637-646,共10页
Vibration induced by shield construction can lead to liquefaction of saturated sand.Based on FLAC3D software,a numerical model of tunnel excavation is established and sinusoidal velocity loads with different frequenci... Vibration induced by shield construction can lead to liquefaction of saturated sand.Based on FLAC3D software,a numerical model of tunnel excavation is established and sinusoidal velocity loads with different frequencies are applied to the excavation face.The pattern of the excess pore pressure ratio with frequency,as well as the dynamic response of soil mass under different frequency loads before excavation,is analyzed.When the velocity sinusoidal wave acts on the excavation surface of the shield tunnel with a single sand layer,soil liquefaction occurs.However,the ranges and locations of soil liquefaction are different at different frequencies,which proves that the vibration frequency influences the liquefaction location of the stratum.For sand-clay composite strata with liquefiable layers,the influence of frequency on the liquefaction range is different from that of a single stratum.In the frequency range of 5-30 Hz,the liquefaction area and surface subsidence decrease with an increase in vibration frequency.The research results in this study can be used as a reference in engineering practice for tunneling liquefiable strata with a shield tunneling machine. 展开更多
关键词 shield tunnel liquefiable formation FLAC3d numerical simulation excess pore pressure ratio dynamic response analysis
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Stochastic analysis of excavation-induced wall deflection and box culvert settlement considering spatial variability of soil stiffness
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作者 Ping Li Shiwei Liu +2 位作者 Jian Ji Xuanming Ding Mengdie Bao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3256-3270,共15页
In this study, a three-dimensional (3D) finite element modelling (FEM) analysis is carried out to investigate the effects of soil spatial variability on the response of retaining walls and an adjacent box culvert due ... In this study, a three-dimensional (3D) finite element modelling (FEM) analysis is carried out to investigate the effects of soil spatial variability on the response of retaining walls and an adjacent box culvert due to a braced excavation. The spatial variability of soil stiffness is modelled using a variogram and calibrated by high-quality experimental data. Multiple random field samples (RFSs) of soil stiffness are generated using geostatistical analysis and mapped onto a finite element mesh for stochastic analysis of excavation-induced structural responses by Monte Carlo simulation. It is found that the spatial variability of soil stiffness can be described by an exponential variogram, and the associated vertical correlation length is varied from 1.3 m to 1.6 m. It also reveals that the spatial variability of soil stiffness has a significant effect on the variations of retaining wall deflections and box culvert settlements. The ignorance of spatial variability in 3D FEM can result in an underestimation of lateral wall deflections and culvert settlements. Thus, the stochastic structural responses obtained from the 3D analysis could serve as an effective aid for probabilistic design and analysis of excavations. 展开更多
关键词 Three-dimensional(3d) Geostatistical analysis Random finite element modelling(FEM) Spatial variability of soil stiffness
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Use of high-resolution X-ray computed tomography and 3D image analysis to quantify mineral dissemination and pore space in oxide copper ore particles 被引量:8
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作者 Bao-hua Yang Ai-xiang Wu +2 位作者 Guillermo A.Narsilio Xiu-xiu Miao Shu-yue Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第9期965-973,共9页
Mineral dissemination and pore space distribution in ore particles are important features that influence heap leaching performance. To quantify the mineral dissemination and pore space distribution of an ore particle,... Mineral dissemination and pore space distribution in ore particles are important features that influence heap leaching performance. To quantify the mineral dissemination and pore space distribution of an ore particle, a cylindrical copper oxide ore sample (I center dot 4.6 mm x 5.6 mm) was scanned using high-resolution X-ray computed tomography (HRXCT), a nondestructive imaging technology, at a spatial resolution of 4.85 mu m. Combined with three-dimensional (3D) image analysis techniques, the main mineral phases and pore space were segmented and the volume fraction of each phase was calculated. In addition, the mass fraction of each mineral phase was estimated and the result was validated with that obtained using traditional techniques. Furthermore, the pore phase features, including the pore size distribution, pore surface area, pore fractal dimension, pore centerline, and the pore connectivity, were investigated quantitatively. The pore space analysis results indicate that the pore size distribution closely fits a log-normal distribution and that the pore space morphology is complicated, with a large surface area and low connectivity. This study demonstrates that the combination of HRXCT and 3D image analysis is an effective tool for acquiring 3D mineralogical and pore structural data. 展开更多
关键词 high-resolution X-ray computed tomography 3d image analysis ore particles mineral dissemination pore space
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Elastoplastic 3D Deformation and Stress Analysis of Strip Rolling 被引量:5
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作者 Liu Yuli Jin Xiaoguang Lian Jiachuang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 1998年第2期30-33,共6页
An elastoplastic method for analyzing the 3D deformation, stress and transverse distribution of tension stress during cold strip rolling is developed. The analysis is based on the elastoplastic variational principle i... An elastoplastic method for analyzing the 3D deformation, stress and transverse distribution of tension stress during cold strip rolling is developed. The analysis is based on the elastoplastic variational principle in which a kinematically admissible velocity field is constructed with the lateral flow function as an unknown function. The stress distribution and volume strain distribution are obtained by solving the simultaneous equations formed by the longitudinal differential equation of equilibrium and constitutive equations. The lateral flow function is determined by minimizing the total energy dissipation rate. Experimental investigation was carried out on a reversible cold mill. The front tension stress distributions in cold rolled strips were measured by a multi roll segmented tension sensing shapemeter. The calculated results are in good agreement with the measured ones. 展开更多
关键词 strip rolling 3d deformation and stress elastoplastic analysis variational principle
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