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Character Modelling with Sketches and ODE-Based Shape Creation
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作者 Ouwen Li Haibin Fu +6 位作者 Shaojun Bian Xiaosong Yang Xiaogang Jin Andres Iglesias Algirdas Noreika Lihua You Jian Jun Zhang 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE CSCD 2023年第3期720-751,共32页
Character models have enormous applications in industry.Efficient creation of detailed character models is an important topic.This paper proposes a new and easy-to-use technique to quickly create detailed character mo... Character models have enormous applications in industry.Efficient creation of detailed character models is an important topic.This paper proposes a new and easy-to-use technique to quickly create detailed character models from sketches.The proposed technique consists of two main components:primitive deformer and shape generators.With this technique,2D silhouette contours of a character model are drawn or extracted from an image or sketch.Then,proper geometric primitives are selected and aligned with the corresponding 2D silhouette contours.After that,a primitive deformer is used to create a base mesh and three shape generators are used to add 3D details to the base mesh.The primitive deformer and three shape generators are developed from ODE-driven deformations.The primitive deformer deforms the aligned geometric primitives to exactly match the 2D silhouette contours in one view plane and obtains a base mesh of a character model consisting of deformed primitives.The shape generators are used to add 3D details to the base mesh by creating local 3D models.The experimental results demonstrate that the new technique can quickly create detailed 3D character models from sketches with few manual operations.The new technique is physics-based and easy to learn and use. 展开更多
关键词 Sketch-based character modelling shape generators ordinary differential equations finite difference solution
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Comprehensive Characterization Model of Integrated Cotton Fiber Quality Index 被引量:1
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作者 刘贵 杨瑜榕 +2 位作者 王明葵 YANG Shouren 于伟东 《Journal of Donghua University(English Edition)》 EI CAS 2011年第4期379-383,共5页
An integrated cotton fiber quality index (ICFQI) model with cotton fiber qualities which can directly express cotton fiber integrated quality and spinning yarn quality was studied. The fiber length, strength, Micron... An integrated cotton fiber quality index (ICFQI) model with cotton fiber qualities which can directly express cotton fiber integrated quality and spinning yarn quality was studied. The fiber length, strength, Micronalre (fiber fineness and fiber maturity), uniformity of fiber length, and short fiber content are the pivotal indexes expressing ICFQI. All of the results above are the basic knowledge to build up the models of ICFQI. According to spinning consistency index (SCI), spinning strength and spinning yarn integrated quality, ICFQI was the best choice. As the methods of ICFQI had quite a lot of advantages like explicit mechanism, few independent variables. The integrated fiber quality index had a significant positive correlation with yarn strength and spinning consistency, significant negative correlation with yarn evenness and yarn thin places. In additional, the model of the relationship between ICFQI and SCI was established as: SCI=0. 235 6·ICFQI +56.153. It was concluded that ICFQI value was the shared reference index for the testing of fiber inspection agency and the selection and distribution of raw cotton bales by textile mills. 展开更多
关键词 fiber quality integrated cotton fiber quality index(ICFQ1) comprehensive characterization model
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V2V Channel Characterization and Modeling for Underground Parking Garages 被引量:3
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作者 Mi Yang Bo Ai +4 位作者 Ruisi He Liang Chen Xue Li Jianzhi Li Zhangdui Zhong 《China Communications》 SCIE CSCD 2019年第9期93-105,共13页
As an important part of the intelligent transportation system(ITS),vehicle-to-vehicle(V2V)communication will improve the safety and efficiency of the transportation system by realizing the information transmission bet... As an important part of the intelligent transportation system(ITS),vehicle-to-vehicle(V2V)communication will improve the safety and efficiency of the transportation system by realizing the information transmission between vehicles.The underground parking garage is a typical scenario in V2V communication,but as an indoor environment,it is different from the conventional outdoor road scenarios significantly.Therefore,the purpose of this paper is to analyze and model the V2V channel characteristics of an underground garage.In this paper,a novel channel measurement carried out in the underground garage is first introduced.Considering that there are a lot of obstacles in an underground garage,the non-line-of-sight(NLoS)condition is taken into account during the measurement.Then,channel characteristic parameters,including large-scale fading,delay spread,and K-factor,are analyzed based on the measured data.In addition,we also carry out channel angle of arrival analysis,show the distribution of azimuth of arrival(AOA)and elevation of arrival(EOA)of multipath components(MPC),and conduct a statistical analysis of the angular spread.In the process of analysis and modeling,we focus on the differences between line-of-sight(LoS)and NLoS conditions.The analysis and conclusions presented in this paper will enrich the understanding of V2V channel and benefit the design of V2V communications. 展开更多
关键词 V2V CHANNEL modelING CHANNEL characterIZATION
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CHARACTERIZATIONS ON THE THIXOTROPY-LOOP TESTS USING UCM MODEL WITH A RATE-TYPE KINETIC EQUATION 被引量:1
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作者 Shu-xin Huang Chuan-jing Lu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第6期609-617,共9页
The theoretical characterizations on the triangular-form thixotropy-loop tests of an LDPE melt (PE-FSB- 23D022/Q200) were conducted in the present paper by using a new thixotropy model, which is constituted by the u... The theoretical characterizations on the triangular-form thixotropy-loop tests of an LDPE melt (PE-FSB- 23D022/Q200) were conducted in the present paper by using a new thixotropy model, which is constituted by the upper convected Maxwell model and a rate-type kinetic equation. The new thixotropic Maxwell model can partially describe well three reported thixotropy-loop experiments by comparison with the previous calculations of the variant form of the thixotropy-type Huang model. It is noted that the stress deviations between the experiments and the predictions of the new thixotropic Maxwell model are much slighter than those deviations obtained by using the variant Huang model at the same condition, although both models include five parameters. The constitution of the new thixotropic Maxwell model is more reasonable than that of the variant Huang model. 展开更多
关键词 Thixotropy-loop tests Theoretical characterization Thixotropy models.
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Inclusion complexes of cefuroxime axetil with β-cyclodextrin:Physicochemical characterization, molecular modeling and effect of Larginine on complexation 被引量:3
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作者 Sarika Sapte Yogesh Pore 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第5期300-306,共7页
The inclusion complexes of poorly water-soluble cephalosporin, cefuroxime axetil(CFA), were prepared with β-cyclodextrin(βCD) with or without addition of L-arginine(ARG) to improve its physicochemical properties. We... The inclusion complexes of poorly water-soluble cephalosporin, cefuroxime axetil(CFA), were prepared with β-cyclodextrin(βCD) with or without addition of L-arginine(ARG) to improve its physicochemical properties. We also investigated the effect of ARG on complexation efficiency(CE) of βCD towards CFA in an aqueous medium through phase solubility behaviour according to Higuchi and Connors. Although phase solubility studies showed AL(linear) type of solubility curve in presence and absence of ARG, the CE and association constant(Ks) of βCD towards CFA were significantly promoted in presence of ARG,justifying its use as a ternary component. The solid systems of CFA with βCD were obtained by spray drying technique with or without incorporation of ARG and characterized by differential scanning calorimetry(DSC), X-ray powder diffractometry(XRPD), scanning electron microscopy(SEM), and saturation solubility and dissolution studies. The molecular modeling studies provided a better insight into geometry and inclusion mode of CFA inside βCD cavity. The solubility and dissolution rate of CFA were significantly improved upon complexation with βCD as compared to CFA alone. However, ternary system incorporated with ARG performed better than binary system in physicochemical evaluation. In conclusion, ARG could be exploited as a ternary component to improve the physicochemical properties of CFA via βCD complexation. 展开更多
关键词 CEFUROXIME axetil Β-CYCLODEXTRIN INCLUSION complex MOLECULAR modeling PHYSICOCHEMICAL characterization
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Characterization and Modelling of High Temperature Flow Behaviour of V Modified 2.25Cr-1Mo Heat Resistant Steel Plate
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作者 刘自立 刘春明 +1 位作者 DING Jianhua ZHANG Hanqian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第1期192-199,共8页
In order to study the high temperature flow behaviour of the V modified 2.25Cr-1Mo steel plate to guide the industrial rolling practice, the hot compression tests were carried out at the temperatures from 900 ℃ to 11... In order to study the high temperature flow behaviour of the V modified 2.25Cr-1Mo steel plate to guide the industrial rolling practice, the hot compression tests were carried out at the temperatures from 900 ℃ to 1150 ℃ and the strain rates from 0.01s^-1 to 1 s^-1 on Thermecmastor-Z equipment. Based on the experimental data of the hot compression tests, a kind of Arrhenius-type constitutive equation was developed.The equation can accurately show the relationship between the flow stress and the deformation temperature, the strain and the strain rate. The measured true stress-true strain curves exhibit two kinds of flow stress curves. Moreover, the forming mechanisms of these two types curves were explained by softening, wok hardening theory as well as metallographic and hardness experimental results. The accuracy of the developed Arrheniustype constitutive equation was identified by three kinds of statistic parameters and also by comparison of the measured and predicted data. The reasonable value of the three types of statistic parameters and the good agreement between the experimental and predicted data can confirm the validity of the developed Arrheniustype constitutive equation for V modified 2.25 Cr-1 Mo heat resistant steel plate. 展开更多
关键词 flow behaviour characterIZATION modelling V MODIFIED 2.25CR-1MO STEEL heat resistant STEEL PLATE
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Computer Modeling and Simulation of Ultrasonic System for Material Characterization 被引量:1
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作者 Yogendra B. Gandole 《Modeling and Numerical Simulation of Material Science》 2011年第1期1-13,共13页
In this paper the system for simulation, measurement and processing in graphical user interface implementa- tion is presented. The received signal from the simulation is compared to that of an actual measurement in th... In this paper the system for simulation, measurement and processing in graphical user interface implementa- tion is presented. The received signal from the simulation is compared to that of an actual measurement in the time domain. The comparison of simulated, experimental data clearly shows that acoustic wave propaga- tion can be modeled. The feasibility has been demonstrated in an ultrasound transducer setup for material property investigations. The results of simulation are compared to experimental measurements. Results ob- tained fit some much with those found in experiment and show the validity of the used model. The simula- tion tool therefore provides a way to predict the received signal before anything is built. Furthermore, the use of an ultrasonic simulation package allows for the development of the associated electronics to amplify and process the received ultrasonic signals. Such a virtual design and testing procedure not only can save us time and money, but also provide better understanding on design failures and allow us to modify designs more efficiently and economically. 展开更多
关键词 modelING Simulation ULTRASONIC MATERIAL characterIZATION SIGNAL PROCESSING
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Characterization of Metallic Formation on Ion Exchange/Chelating Resins by Various Metal Groups and Extrapolation to Molecular Models
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作者 Sean Dudley Recep Avci +4 位作者 William Gleason William Hill Jacob Howery Miles Jaqua Daisy Margrave 《Journal of Minerals and Materials Characterization and Engineering》 2018年第1期72-85,共14页
This paper examines the metallic rare earth element (REE) formations that grow on ion exchange/chelating resins. Formation of these stabilized metallic structures leads to composite particle destruction and appears to... This paper examines the metallic rare earth element (REE) formations that grow on ion exchange/chelating resins. Formation of these stabilized metallic structures leads to composite particle destruction and appears to be the result of the dynamic environment of the batch experimentation. Polymeric structure, electron availability, pH, kinetic factors, and the REE f-orbitals play significant roles in the formation of the organometallic framework. f-orbitals are largely still not understood to a great extent but this work serves to elucidate the larger role they may play in ligand interactions. Molecular modeling was utilized as a secondary component in investigating rare earth element (REE) deposition onto ion exchange/chelating resins. Modeling of the f-orbital frontier regions and the application of the HOMO-LUMO transition’s effect on molecular transfer and stability is discussed. Advanced metallic loading, in the manner of an organometallic structure, shows short-term stability resulting in particle destruction as increased REE is adsorbed. 展开更多
关键词 RARE EARTH Recovery Polymer modeling characterIZATION
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Molecular Characterization, 3D Modeling of Grass Carp Interleukin-10 Receptor 1 (IL10R1)
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作者 He Wei Shangnian Wang +2 位作者 Lei Qin Xinyan Wang Hong Zhou 《Engineering(科研)》 2013年第10期214-219,共6页
Interleukin-10 (IL-10) is an important cytokine that plays a pivotal role in natural and adaptive immune systems. However, in lower vertebrates, especially in teleost the receptor of this cytokine is still largely unk... Interleukin-10 (IL-10) is an important cytokine that plays a pivotal role in natural and adaptive immune systems. However, in lower vertebrates, especially in teleost the receptor of this cytokine is still largely unknown. This paper described the cloning and characterization of grass carp interleukin-10 receptor 1 (gcIL10R1) and the 3D structure of its extracellular domain was predicted. The gcIL10R1 cDNA included 180 bp5’ untranslated region (UTR), 870 bp3’ UTR and an open reading frame (ORF) of 1632 bp. The ORF was found to encode a 543 amino acid protein with a putative JAK1 binding site, one STAT3 binding site. The phylogenetic analysis clusters gcIL10R1 with other teleost IL10R1s but independently of the amphibian, avian and mammalian IL10R1s. The 3D structure of its extracellular domain was the first homology model of a fish IL10R1 that revealed a high similarity with its mammalian and avian counterparts. 展开更多
关键词 GRASS CARP INTERLEUKIN-10 RECEPTOR 1 Structure characterization 3D modeling
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Synthesis and Characterization of Porphyrin-Trisbenzimidazole Dinucleating Ligand and Its Heterodinuclear Complex as CcO Active Site Model
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作者 Lu Wei-bing, Wang Cun-xin, Deng Li-zhi, Zhou Xiao-hai, Ren Jian-guoCollege of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第02A期428-432,共5页
A new dinucleating ligand having two metalbinding sites has been designed and synthesized as model ligand for Cytochrome c Oxidase. The corresponding heterodinuclear complex, as an active site model of Cytochrome c Ox... A new dinucleating ligand having two metalbinding sites has been designed and synthesized as model ligand for Cytochrome c Oxidase. The corresponding heterodinuclear complex, as an active site model of Cytochrome c Oxidase, consisting of a porphyrinatocobalt compound covalently linked with a copper derivative of tris(2-benzimidazylmethyl) amine bearing three benzimidazole ligands for copper was synthesized and spectroscopically characterized. The spectra data suggest that there are interactions between the cobalt and copper coordination units. The cobalt is coordinated to four central nitrogens of the porphyrin and the copper has pentacoordinate geometry with the four tertiary amine nitrogens and a chloride. 展开更多
关键词 Key words Cytochrome c Oxidase model compound SYNTHESIS characterIZATION
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Evaluation of Unknown Groundwater Contaminant Sources Characterization Efficiency under Hydrogeologic Uncertainty in an Experimental Aquifer Site by Utilizing Surrogate Models
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作者 Shahrbanoo Hazrati-Yadkoori Bithin Datta 《Journal of Water Resource and Protection》 2017年第13期1612-1633,共22页
Characterization of unknown groundwater contaminant sources is an important but difficult step in effective groundwater management. The difficulties arise mainly due to the time of contaminant detection which usually ... Characterization of unknown groundwater contaminant sources is an important but difficult step in effective groundwater management. The difficulties arise mainly due to the time of contaminant detection which usually happens a long time after the start of contaminant source(s) activities. Usually, limited information is available which also can be erroneous. This study utilizes Self-Organizing Map (SOM) and Gaussian Process Regression (GPR) algorithms to develop surrogate models that can approximate the complex flow and transport processes in a contaminated aquifer. The important feature of these developed surrogate models is that unlike the previous methods, they can be applied independently of any linked optimization model solution for characterizing of unknown groundwater contaminant sources. The performance of the developed surrogate models is evaluated for source characterization in an experimental contaminated aquifer site within the heterogeneous sand aquifer, located at the Botany Basin, New South Wales, Australia. In this study, the measured contaminant concentrations and hydraulic conductivity values are assumed to contain random errors. Simulated responses of the aquifer to randomly specified contamination stresses as simulated by using a three-dimensional numerical simulation model are utilized for initial training of the surrogate models. The performance evaluation results obtained by using different surrogate models are also compared. The evaluation results demonstrate the different capabilities of the developed surrogate models. These capabilities lead to development of an efficient methodology for source characterization based on utilizing the trained and tested surrogate models in an inverse mode. The obtained results are satisfactory and show the potential applicability of the SOM and GPR-based surrogate models for unknown groundwater contaminant source characterization in an inverse mode. 展开更多
关键词 Surrogate models UNKNOWN GROUNDWATER Contamination Sources Source characterIZATION EXPERIMENTAL SITE Contaminated Aquifers
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地球物理技术向油藏开发延伸的现状与展望
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作者 黄旭日 《石油物探》 北大核心 2025年第1期15-31,共17页
地球物理技术近几十年来一直不断地向油气藏开发延伸,在面向目标成像、岩石物理、多约束反演、地震约束和驱动建模、油藏动态监测与表征以及多数据融合与智能化等多方面取得了长足的进步。地球物理技术向油藏开发延伸是地球物理技术本... 地球物理技术近几十年来一直不断地向油气藏开发延伸,在面向目标成像、岩石物理、多约束反演、地震约束和驱动建模、油藏动态监测与表征以及多数据融合与智能化等多方面取得了长足的进步。地球物理技术向油藏开发延伸是地球物理技术本身发展的需要,也是更好开发油气藏的需要。与勘探地球物理相比,面向油藏开发领域的地球物理技术,由于数据条件、关键技术问题与目标的变化而形成了具有自身独特特征的技术体系。旨在简单总结和梳理该领域的发展和现状,目的是能和读者分享作者对未来技术发展的思考,希望对读者有所启发。 展开更多
关键词 油藏开发 油藏地球物理 动态监测 动态表征 油藏模型 多约束地震反演 多数据融合
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纳米流体化学组分模拟表征方法研究及应用
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作者 高杰 王涛 +3 位作者 王飞 田苗 张宇 于萌 《能源与环保》 2025年第2期106-111,共6页
为了做好纳米驱油技术的油藏方案设计及准确预测技术效果,在连通性模型的基础上耦合纳米流体的驱油机理,考虑纳米颗粒吸附沉降引起的岩石孔隙度和渗透率变化及增黏效应,建立纳米流体化学组分模拟表征方法,并对该方法与数值模拟软件及实... 为了做好纳米驱油技术的油藏方案设计及准确预测技术效果,在连通性模型的基础上耦合纳米流体的驱油机理,考虑纳米颗粒吸附沉降引起的岩石孔隙度和渗透率变化及增黏效应,建立纳米流体化学组分模拟表征方法,并对该方法与数值模拟软件及实验结果进行了对比,验证了该方法的正确性和可靠性。对主要参数进行了敏感性分析,发现随着纳米注入浓度增加、注入时间提前及注入PV数增加,驱油效果越好。以X油田为例,拟合A1井组纳米驱油前后累产油及含水率,拟合率达到90%以上,拟合精度较高,表明该方法可以实现生产指标的拟合,可以指导纳米驱及水驱方案的效果预测。 展开更多
关键词 纳米流体 表征方法 吸附量 增黏效应 连通性模型
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考虑测点变形关联关系的拱坝变形表征模型
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作者 石中文 李军 +4 位作者 潘文明 贾海磊 翟俊杰 叶胜 郝洁 《水电能源科学》 北大核心 2025年第2期151-154,共4页
变形是拱坝结构性态变化最直观的表征指标,因此通常在拱坝上布置变形监测点,以获取拱坝的变形信息。基于拱坝变形监测数据,充分考虑大坝内部各测点变形之间存在的复杂关联关系,从拱坝结构内部关联及信息融合的角度,提出了确定与待分析... 变形是拱坝结构性态变化最直观的表征指标,因此通常在拱坝上布置变形监测点,以获取拱坝的变形信息。基于拱坝变形监测数据,充分考虑大坝内部各测点变形之间存在的复杂关联关系,从拱坝结构内部关联及信息融合的角度,提出了确定与待分析测点变形显著线性关联及强非线性关联关系测点的技术,据此构建了利用强关联测点对待分析测点变形进行表征的模型,通过具体工程实例,验证了模型的有效性,为拱坝变形性态分析提供了新的手段。 展开更多
关键词 拱坝 变形监测数据 关联关系 表征模型
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间歇递增加载条件下裂隙煤体损伤的宏-细观特征
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作者 李金雨 王月然 +2 位作者 赵洪宝 丁姝慧 陈塱迪 《安全与环境学报》 北大核心 2025年第1期121-131,共11页
为探究裂隙煤体在真实采动效应下的损伤特征,开展了不同裂隙试样在间歇递增加载条件下的损伤演化规律研究,通过系统分析其力学及声发射特征参量演化规律、宏观裂纹表征及各向位移趋势,最终得出间歇递增加载过程中裂隙煤体损伤的宏-细观... 为探究裂隙煤体在真实采动效应下的损伤特征,开展了不同裂隙试样在间歇递增加载条件下的损伤演化规律研究,通过系统分析其力学及声发射特征参量演化规律、宏观裂纹表征及各向位移趋势,最终得出间歇递增加载过程中裂隙煤体损伤的宏-细观特征。结果表明,(1)试样的承载能力与衰减特征:倾角因素更能影响煤体的损伤程度,岩桥倾角组煤体稳定性更强;各组内部起裂应力、抗拉强度与稳定性排序基本一致。(2)试样的损伤演化及破坏模式:单裂隙组属脆性破坏,位移趋势为Ⅰ型位移场与Ⅲ型位移场耦合相关破坏,双裂隙组属延性破坏,位移趋势为Ⅱ型位移场相关破坏;其中α=60°组损伤最严重且沿次生裂隙扩展。(3)建立了基于声发射特征参量的裂隙煤体损伤模型,并验证了模型的合理性。 展开更多
关键词 安全工程 裂隙煤体 离散元程序 损伤演化 模型表征
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隧洞开挖变形特性参数化表征与代理模型预测
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作者 刘志峰 徐磊 +2 位作者 夏超杰 陈金鹏 严鑫鹏 《水资源与水工程学报》 北大核心 2025年第1期191-198,共8页
隧洞在开挖面推进过程中的变形特性是确定其开挖支护方案的重要依据。为解决传统仿真分析预测隧洞开挖变形特性工作量大、耗时长的难题,在辨识隧洞开挖变形特性曲线几何特征的基础上,提出采用三参数指数型函数对该曲线进行参数化表征;... 隧洞在开挖面推进过程中的变形特性是确定其开挖支护方案的重要依据。为解决传统仿真分析预测隧洞开挖变形特性工作量大、耗时长的难题,在辨识隧洞开挖变形特性曲线几何特征的基础上,提出采用三参数指数型函数对该曲线进行参数化表征;进一步通过综合运用拉丁超立方抽样技术与Kriging代理模型,提出了一种可实现隧洞开挖变形特性快速预测的代理模型方法,并给出了实施流程。以某输水隧洞工程为例,构建了以埋深与围岩力学参数为输入、以开挖变形特性曲线的表征参数为输出的预测代理模型,并应用于3个典型洞段的开挖变形特性曲线预测。结果表明:不同输入参数下的预测结果与有限元仿真分析结果均吻合较好,验证了所提方法具有可靠的预测精度及良好的适应性,且相较于传统仿真分析方法,具有显著的效率优势。 展开更多
关键词 水工隧洞 开挖变形特性 快速预测 参数化表征 代理模型
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力学性能可调的可逆装配力学超材料性能表征
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作者 吴琪 杨宇 +2 位作者 芦奕菲 鲍盘盘 王志刚 《机械强度》 北大核心 2025年第1期92-106,共15页
点阵结构因其高比强度和比刚度成为航空、航天、汽车等领域的研究热点。增材制造技术的发展使得具有复杂几何外形和特殊力学性能的力学超材料点阵结构的加工成为可能。但传统增材制造工艺难以协调此类结构在成本、几何尺寸和精度之间的... 点阵结构因其高比强度和比刚度成为航空、航天、汽车等领域的研究热点。增材制造技术的发展使得具有复杂几何外形和特殊力学性能的力学超材料点阵结构的加工成为可能。但传统增材制造工艺难以协调此类结构在成本、几何尺寸和精度之间的矛盾。鉴于此,提出了一种可逆装配的力学超材料结构概念及基础体素结构的连接方法,可有效克服制造装备的尺寸限制,并可以通过不同排列组合构建力学性能丰富的宏观点阵结构。针对可逆装配的基础体素型式,通过参数化建模的方法分析了体素几何特征、相对密度和体素数目等参数对其力学性能的影响,并与实验结果进行了对比。结果表明,所提出的3种基础体素刚性差异较大,泊松比覆盖了由负到正的范围。因此,使用这3种基础体素的不同组合方式可以产生不同力学性能分布的宏观结构,从而证明了采用这3种体素作为可逆装配结构基本体素的合理性。此外,所给出的几何尺寸与力学性能之间的数学关系可为此类力学超材料的工程应用提供指导。 展开更多
关键词 可逆装配 力学超材料 参数化建模 点阵结构 性能表征
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河流决口扇沉积特征和数值模拟:以内蒙古凉城县东营子扇为例
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作者 张洋 江山 曲洋洋 《科学技术与工程》 北大核心 2025年第6期2324-2331,共8页
决口扇的发育过程和演化模式对河流相储层预测和剩余油挖潜具有重要意义。以内蒙古凉城县东营子扇为例,基于卫星影像和野外考察,分析东营子扇沉积特征。利用沉积数值模拟,设置了模拟网格、模拟参数和边界条件,建立了决口扇的数值模型,... 决口扇的发育过程和演化模式对河流相储层预测和剩余油挖潜具有重要意义。以内蒙古凉城县东营子扇为例,基于卫星影像和野外考察,分析东营子扇沉积特征。利用沉积数值模拟,设置了模拟网格、模拟参数和边界条件,建立了决口扇的数值模型,分析了不同数值模拟阶段决口扇的沉积厚度、河道流速、含砂率平面分布和垂向沉积结构,总结了决口扇的沉积模式、砂体类型和砂体分布。研究表明,东营子扇由决口水道、复合内扇和外扇组成。气候从湿润到干旱的演变过程中,河流决口扇的形成过程可以划分为河流决口期、内扇萌芽期、内扇繁盛期和外扇形成期4个阶段,随着洪水水动力由峰值下降,决口水道、复合内扇和外扇依次形成。复合内扇和外扇是砂岩富集带,是勘探期有利的砂体类型。决口水道是泥岩富集带,是主要的隔夹层类型,周缘的复合内扇是油气田开发后期剩余油富集的主要场所。 展开更多
关键词 曲流河 正演模拟 泛滥平原 储层表征 剩余油
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含构造煤组合体受载裂隙动态演化规律
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作者 赵鹏翔 刘莹莹 +4 位作者 李树刚 刘妍群 刘云川 王捞捞 陆卫东 《煤田地质与勘探》 北大核心 2025年第3期167-176,共10页
【目的】构造煤裂隙发育对开采扰动下组合煤体动力灾害诱发具有重要影响作用,但影响规律尚不明晰。【方法】利用NanoVoxel-3000岩土多尺度高分辨综合扫描分析系统,开展含构造煤组合体单轴压缩CT扫描实验,通过Avizo重构软件重构细观几何... 【目的】构造煤裂隙发育对开采扰动下组合煤体动力灾害诱发具有重要影响作用,但影响规律尚不明晰。【方法】利用NanoVoxel-3000岩土多尺度高分辨综合扫描分析系统,开展含构造煤组合体单轴压缩CT扫描实验,通过Avizo重构软件重构细观几何结构,获得内部三维裂隙可视化模型。【结果和结论】结果表明:裂隙最先在构造煤中产生,裂隙扩展路径分别向上原生结构煤、下原生结构煤发育,径向、纵向裂隙数量总量分别达到7354、1901条;内部裂纹分支数目不断增大,界面破坏裂隙的倾向分布、倾角变化也越复杂,上界面裂隙散射角最终为86°、119°、124°、137°,下界面裂隙散射角为116°。受载过程中,试件整体呈组合破裂模式−倒“V”形+丛状裂隙,裂隙主要集中在构造煤中,占总裂隙的78.5%,裂隙体积和裂隙率呈现降低−缓慢上升−急剧上升−缓慢上升的发展规律。主裂隙长度由44.7 mm增长到99.4 mm,裂隙扩展速度呈现降低−上升−降低的发展规律。通过细观损伤力学模型、两参Weibull函数,构建含构造煤组合体试件裂隙扩展表征模型,建立组合体试件主裂隙形成路径判定流程,通过Matlab软件验证主裂隙路径形成判定的合理性,发现相对误差为1.54%~4.21%,验证了主裂隙路径形成判定的有效性,揭示受载作用下含构造煤组合体裂隙动态演化规律,为研究组合煤层开采扰动下煤岩动力灾害诱发因素提供理论依据。 展开更多
关键词 含构造煤组合体 CT扫描 单轴压缩 裂隙演化 裂隙扩展表征模型
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基于深度学习数据融合的测井数据精细表征
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作者 孙正心 金衍 +1 位作者 孟翰 郭旭洋 《石油科学通报》 2025年第1期75-86,共12页
测井曲线记录钻井过程中地层的物理参数,在研究岩石特性、评估油气藏资源及揭示储层分布等方面具有重要意义。随着油气勘探的深入,隐蔽油气藏的复杂性不断增加,而传统测井数据分辨率较低的局限性,难以满足薄互层储层改造选点的需求,亟... 测井曲线记录钻井过程中地层的物理参数,在研究岩石特性、评估油气藏资源及揭示储层分布等方面具有重要意义。随着油气勘探的深入,隐蔽油气藏的复杂性不断增加,而传统测井数据分辨率较低的局限性,难以满足薄互层储层改造选点的需求,亟待开发高分辨率的测井数据精细解释方法。本研究提出了一种基于ResNet50回归算法的储层预测模型。该模型将能够捕捉复杂垂向地质细节的纵向连续光学薄片数据,与5种常规测井参数相结合,提升储层分析的精度。通过对某井区二叠系地层的5个井段数据进行验证,使用连续的570张地层图片样本与测井数据进行训练与预测,模型将测井数据分辨率从12.5 cm提升至6.25 cm,显著提高了测井数据的精度和分辨率。本研究使用3种公认的定量评估指标决定系数(R^(2))、均方根误差(RMSE)和平均绝对误差(MAE)对模型性能进行了全面评估。结果表明,该模型在声波时差(AC)、补偿中子(CNL)、电阻率(RT)和伽马(GR)参数的预测中表现较为准确,平均误差低于0.094,展示出模型在预测精度上的可靠性与优异性。然而,在密度(DEN)参数的预测中,模型在岩性变化较大或地质条件复杂的井段中受到了一定影响。 展开更多
关键词 数据融合 测井参数精细表征 ResNet50 深度学习模型 储层精细化建模
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