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Symbolic Design Strategies for Film and Television Character Modeling in Cross-Cultural Contexts
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作者 Jianwei Yang 《Journal of Contemporary Educational Research》 2025年第10期369-375,共7页
Against the backdrop of the deep integration of the global film and television industry,character design has long transcended the mere pursuit of aesthetics and has become a key symbolic system that carries cultural i... Against the backdrop of the deep integration of the global film and television industry,character design has long transcended the mere pursuit of aesthetics and has become a key symbolic system that carries cultural information,builds identity recognition,and drives narrative.This article,by integrating semiotic theory and cultural dimension analysis,deeply dissects the core functions and common predicaments(stereotypes,cultural misinterpretation)of formative symbols in cross-cultural communication and systematically proposed four core design strategies:“extraction and translation of cultural symbols,”“visual mapping of cultural dimensions,”“symbolic support of narrative functions,”and“cultural decoding presuppositions for target audiences.”This article holds that successful cross-cultural modeling design should be committed to creative transformation on the basis of respecting the authenticity of culture,constructing a visual symbol system that combines cultural depth and universal appeal,and ultimately serving global narratives and in-depth cultural dialogues. 展开更多
关键词 Cross-cultural communication Film and television character modeling Cultural dimension
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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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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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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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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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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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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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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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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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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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基于电化学-声学耦合模型的磷酸铁锂电池老化状态表征
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作者 刘素贞 孟维绪 +2 位作者 袁路航 徐志成 金亮 《电工技术学报》 北大核心 2026年第1期329-342,共14页
锂离子电池的寿命衰退与循环老化过程中内部结构的演变密切相关。检测锂离子电池内部结构变化有助于更加准确地评估电池的健康状态,然而,电池的封闭式包装导致难以对其内部直接测量。由于超声波能够检测工件内部结构的演变情况且精度较... 锂离子电池的寿命衰退与循环老化过程中内部结构的演变密切相关。检测锂离子电池内部结构变化有助于更加准确地评估电池的健康状态,然而,电池的封闭式包装导致难以对其内部直接测量。由于超声波能够检测工件内部结构的演变情况且精度较高,可用于无损检测电池内部结构的动态变化。该文基于电极活性颗粒应力应变理论,建立磷酸铁锂电池电化学-声学耦合模型,模拟电池老化过程中内部结构变化,研究不同老化状态下超声信号的响应特性,同时构建声学特征参数随电池老化状态的变化曲线,进一步分析电极结构演化机制,并且搭建实验平台验证耦合模型的正确性。该方法可为分析磷酸铁锂电池的老化机理及无损检测电池健康状态提供全新的视角。 展开更多
关键词 磷酸铁锂电池 电化学-声学耦合模型 循环老化 超声特性 结构演变
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基于C-NEM法的综合交通枢纽城市发展水平测度及特征
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作者 李鹏林 石京 +1 位作者 李可 林春翔 《公路交通科技》 北大核心 2026年第3期150-164,共15页
【目标】全面、客观地评估综合交通枢纽城市发展水平,是明确综合交通枢纽城市发展目标、推进综合交通运输体系建设、优化资源配置的关键。【方法】提出一种基于归一化法、熵值法、映射法和均值法相结合(C-NEM)的综合交通枢纽城市发展水... 【目标】全面、客观地评估综合交通枢纽城市发展水平,是明确综合交通枢纽城市发展目标、推进综合交通运输体系建设、优化资源配置的关键。【方法】提出一种基于归一化法、熵值法、映射法和均值法相结合(C-NEM)的综合交通枢纽城市发展水平测度方法,构建了包含6个维度、20个指标的枢纽城市发展水平指标体系,对中国现有89个国家级综合交通枢纽城市的发展水平进行测算及特征分析。【结果】第1梯队的枢纽城市为上海、北京、广州等9个枢纽城市,第2梯队的枢纽城市以各省省会和计划单列市为主,第3梯队的枢纽城市包括部分省会城市及各省次中心城市,大部分为某一领域发展水平较为突出的枢纽城市。现阶段的枢纽城市可分为成熟型、发展型、起步型这3个类别。中国综合交通枢纽城市在枢纽能级方面普遍较高,设施承载能力优越,集聚辐射水平存在一定区域差异,衔接转换效率高的数量仍然偏少,运输服务品质整体较好,资源配置效能整体上仍有待提升。【结论】所提方法不仅有效提升了枢纽城市发展水平测度的准确性和有效性,还揭示了中国综合交通枢纽城市的发展特征及差异,为国家综合交通枢纽系统的规划、建设与政策制订提供了重要的理论依据。 展开更多
关键词 运输经济 测度模型 C-NEM 枢纽城市 发展水平 特征分析
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基于储集层非均质性的水平井泄油半径分段定量表征
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作者 黄郑 刘宇 +3 位作者 樊晓伊 秦玲 陶帅 杨菲 《新疆石油地质》 北大核心 2026年第2期233-240,共8页
针对稠油油藏水平井蒸汽吞吐后水平段开采不均、精细挖潜难度大,现有方法多将水平段整体计算,忽略非均质性造成的动用不均衡,导致对剩余油分布认识不清、精细挖潜方向不明确,提出了水平井分段泄油半径计算方法,该方法采用声波时差表征... 针对稠油油藏水平井蒸汽吞吐后水平段开采不均、精细挖潜难度大,现有方法多将水平段整体计算,忽略非均质性造成的动用不均衡,导致对剩余油分布认识不清、精细挖潜方向不明确,提出了水平井分段泄油半径计算方法,该方法采用声波时差表征储集层非均质性,以相邻声波时差平均值差异大于15%为标准,对水平井进行分段划分;利用单井采出程度、波及系数与驱油效率的关系,建立泄油半径计算模型,用于分段计算泄油半径,定量表征泄油面积,精准定位剩余油分布区。利用建立的新模型,对春光油田春10区块稠油油藏水平井泄油半径进行定量计算,结果显示:该区储集层非均质性强,利用声波时差将其划分为多段,各段泄油半径变化大,同井变化为5~110 m,水平段内部动用严重不均衡。依据剩余油分布特征,优化靶心方向,精准部署的加密井有效避免了老井泄油波及的影响,取得较好的开发效果。为非均质储集层水平井泄油半径计算提供了新方法,可简便、快速计算单井泄油半径,为稠油油藏蒸汽吞吐后进一步精细开发提供技术支撑。 展开更多
关键词 春光油田 春10区块 稠油油藏 水平井 泄油半径 计算模型 分段定量表征
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粗糙裂隙岩体滚刀破岩及裂纹扩展机制
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作者 王培涛 黄浩 +2 位作者 荆国业 周晓敏 解联库 《应用基础与工程科学学报》 北大核心 2026年第1期211-222,共12页
滚刀破岩工作参数和岩体裂隙物理特征是影响硬岩条件下滚刀破岩机理的重要因素.基于MATLAB与AutoCAD平台分别建立光滑离散节理网络(DFN)模型、粗糙离散节理网络(RDFN)模型和三维方形滚刀模型,结合颗粒流离散元PFC数值模拟方法分析了不... 滚刀破岩工作参数和岩体裂隙物理特征是影响硬岩条件下滚刀破岩机理的重要因素.基于MATLAB与AutoCAD平台分别建立光滑离散节理网络(DFN)模型、粗糙离散节理网络(RDFN)模型和三维方形滚刀模型,结合颗粒流离散元PFC数值模拟方法分析了不同侵岩速度和裂隙面粗糙度的破岩效果.研究结果表明:完整岩石滚刀破岩破坏区由岩石表面逐渐向内部延伸,力链呈发散性分布;滚刀侵岩速度对破坏载荷与裂纹数量变化趋势无明显影响,均以剪切裂纹为主.复杂裂隙岩体破裂中力链与裂纹扩展均沿着破坏裂隙面分布,以张拉裂纹为主.破坏区由初始破坏裂隙面处逐渐贯通岩体表面而形成,RDFN模型的破坏载荷较DFN模型的破坏载荷大.RDFN模型与DFN模型的裂纹扩展和破坏模式均受裂隙面控制,裂隙面粗糙度影响着裂纹扩展方向.该研究成果以期为复杂裂隙岩体滚刀破岩机制研究提供有益参考. 展开更多
关键词 裂隙岩体 滚刀破岩 DFN模型 RDFN模型 离散元 节理面表征
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基于反向传播神经网络的城市环境路径损耗预测研究
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作者 王志鹏 万留进 +3 位作者 李玉生 吴昊 马鑫 行鸿彦 《无线电通信技术》 北大核心 2026年第1期181-188,共8页
针对城市复杂电磁环境下传统经验模型预测精度不足与射线追踪(Ray-Tracing,RT)方法计算效率低下的双重挑战,提出了一种融合卫星影像与三维几何特征的反向传播神经网络(Back Propagation Neural Network,BPNN)路径损耗预测模型。通过整... 针对城市复杂电磁环境下传统经验模型预测精度不足与射线追踪(Ray-Tracing,RT)方法计算效率低下的双重挑战,提出了一种融合卫星影像与三维几何特征的反向传播神经网络(Back Propagation Neural Network,BPNN)路径损耗预测模型。通过整合高分辨率卫星影像的RGB光谱信息与散射体的统计特征,表征电磁传播路径的环境特征,结合经过实测数据校准的RT仿真数据构建数据集。实验结果表明,引入三维环境特征后,预测精度显著提高。相较于不使用三维特征的数据集,均方根误差(Root Mean Square Error,RMSE)下降1.54 dB;与对比的多层感知器(Multi-Layer Perceptron,MLP)和随机森林(Random Forest,RF)模型相比,RMSE分别下降2.21 dB和0.34 dB。同时,BPNN模型的计算时间仅为RT模型的一半左右,且在新场景中与实测数据相比的RMSE为5.27 dB,表现出良好的泛化能力。 展开更多
关键词 路径损耗 反向传播神经网络 信道模型 环境表征
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复合光纤界面残余应力研究进展
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作者 付文浩 黄永刚 +2 位作者 孙诗兵 焦朋 金晓冬 《硅酸盐通报》 北大核心 2026年第3期1006-1017,共12页
在光纤制备过程中,芯层与包层材料参数差异及冷却速率、拉制速度等工艺因素,导致界面产生残余应力,该应力对光纤的光学性能和服役寿命具有重要影响。本文围绕光纤界面残余应力问题,系统综述了近年来基于理论计算、数值模拟和物理模拟等... 在光纤制备过程中,芯层与包层材料参数差异及冷却速率、拉制速度等工艺因素,导致界面产生残余应力,该应力对光纤的光学性能和服役寿命具有重要影响。本文围绕光纤界面残余应力问题,系统综述了近年来基于理论计算、数值模拟和物理模拟等方法在冻结残余应力、热致残余应力和机械残余应力的形成机理与影响后果方面的研究进展,并对光弹性法、微拉曼光谱法和布里渊散射法等界面残余应力表征技术进行了总结与分析,旨在为高性能光纤的制备及界面残余应力的精确调控与表征提供参考。 展开更多
关键词 光纤 界面残余应力 理论计算 数值模拟 物理模拟 表征技术
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电力系统交流可行负荷域的完整刻画方法研究
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作者 姜海鹏 苏珈 +4 位作者 江晓东 杜欣慧 张文轩 常堃 张日新 《太原理工大学学报》 北大核心 2026年第2期219-228,共10页
【目的】静态安全域表示电力系统满足运行约束的可行功率注入的集合。为充分研究和表征电力系统负荷需求的灵活性,将静态安全域投影到负荷需求空间上,定义了交流可行负荷域。【方法】首先,采用非线性交流潮流模型对系统的交流可行负荷... 【目的】静态安全域表示电力系统满足运行约束的可行功率注入的集合。为充分研究和表征电力系统负荷需求的灵活性,将静态安全域投影到负荷需求空间上,定义了交流可行负荷域。【方法】首先,采用非线性交流潮流模型对系统的交流可行负荷域进行完整刻画。同时,为探讨负荷特性对交流可行负荷域的影响,在负荷域模型中引入了描述非线性负荷特性的多项式负荷模型(ZIP负荷模型)。最后,通过数值计算结果,验证了所提刻画方法在完整准确刻画负荷域的优势。【结果】文章通过在IEEE 30节点、IEEE 57节点和IEEE 118节点系统上将该方法与现有的几种方法进行对比,结果表明本文所得刻画结果更精准,验证了所提方法的准确性和优越性。 展开更多
关键词 交流可行负荷域 交流潮流模型 完整刻画 非线性动力系统 ZIP负荷模型
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纳米颗粒增强金属基复合材料温度相关性屈服强度理论表征模型
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作者 王翊霖 李卫国 麻建坐 《应用数学和力学》 北大核心 2026年第1期57-67,共11页
通过定量表征宽温域下,各强化机制对纳米颗粒增强金属基复合材料(nanoparticle reinforced metal matrix composites,NRMMCs)的屈服强度以及晶界滑移对金属基体屈服强度的影响,建立了不含拟合参数的NRMMCs温度相关性屈服强度理论表征模... 通过定量表征宽温域下,各强化机制对纳米颗粒增强金属基复合材料(nanoparticle reinforced metal matrix composites,NRMMCs)的屈服强度以及晶界滑移对金属基体屈服强度的影响,建立了不含拟合参数的NRMMCs温度相关性屈服强度理论表征模型.模型仅需金属基体任意一个参考温度下的屈服强度及相关材料参数,如比热容、热膨胀系数、熔点等,即可预测NRMMCs在任意温度下的屈服强度.模型预测结果与目前获取到的四组所有实验数据均取得了良好的一致性,实现了对NRMMCs宽温域屈服强度的合理预测.在此基础上,探讨了主要强化机制对NRMMCs屈服强度的影响及其随温度和颗粒尺寸的演化规律,为设计和开发适用于宽温域下的NRMMCs提供了理论依据和有效建议。 展开更多
关键词 纳米颗粒增强金属基复合材料 温度相关性 屈服强度 理论表征模型 强化机制
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基于多元线性回归的柴油基础理化性质预测模型
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作者 王先林 唐思扬 +3 位作者 宋磊 钟山 李红娇 梁斌 《石油与天然气化工》 北大核心 2026年第1期113-121,共9页
目的利用组成特征建立柴油性质预测模型,实现高效的性质预测,并分析组成特征对性质的影响。方法根据92组模拟柴油样品数据计算组成特征,根据组成特征(平均相对分子质量、氢碳比、碳数、不饱和度、平均分子芳香烃环数、平均分子环烷烃环... 目的利用组成特征建立柴油性质预测模型,实现高效的性质预测,并分析组成特征对性质的影响。方法根据92组模拟柴油样品数据计算组成特征,根据组成特征(平均相对分子质量、氢碳比、碳数、不饱和度、平均分子芳香烃环数、平均分子环烷烃环数、平均分子总环数)与性质(密度、折光率、运动黏度、动力黏度、表面张力、蒸馏曲线积分)的相关性分析筛选合适的组成特征描述符,通过多元线性回归建立组成特征-性质预测模型并优化,通过标准化将组成特征的尺度统一,重新建模分析组成特征对性质的相对重要性。结果初始模型(氢碳比和碳数)预测密度、折光率、蒸馏曲线积分效果较好(决定系数R^(2)>0.85),但黏度和表面张力精度不足。优化后引入芳香烃环数和环烷烃环数,显著提升了模型性能,除表面张力外,其他性质的R^(2)均大于0.90,平均绝对百分比误差δ_(MAPE)<5%,密度与折光率的R^(2)>0.95。分析表明,碳数主导黏度和蒸馏曲线,芳香烃环数和环烷烃环数对密度影响显著。结论芳香烃环数、环烷烃环数和碳数是影响柴油基础理化性质的关键描述符,能准确预测柴油基础理化性质,该研究为柴油组成设计和性能优化提供了可靠的量化分析工具,对燃料研发具有重要指导意义。 展开更多
关键词 柴油 性质预测模型 组成特征描述符 多元线性回归 基础理化性质
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