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Failure characteristics of three-body model composed of rock and coal with different strength and stiffness 被引量:15
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作者 赵增辉 王渭明 +1 位作者 代春泉 严纪兴 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1538-1546,共9页
Four different types of three-body model composed of rock and coal with different strength and stiffness were established in order to study the failure characteristics of compound model such as roof-coal-floor. Throug... Four different types of three-body model composed of rock and coal with different strength and stiffness were established in order to study the failure characteristics of compound model such as roof-coal-floor. Through stress analysis of the element with variable strength and stiffness extracted from the strong-weak interface, the tri-axial compressive strength of the weak body and strong body near the interface as well as the areas away from the contact surface was found. Then, on the basis of three-dimensional fast Lagrangian method of continua and strain softening constitutive model composed of Coulomb-Mohr shear failure with tensile cut-off, stress and strain relationship of the four three-body combined models were analyzed under different confining pressures by numerical simulation. Finally, the different features of local shear zones and plastic failure areas of the four different models and their development trend with increasing confining pressure were discussed. The results show that additional stresses are derived due to the lateral deformation constraints near the strong-weak interface area, which results in the strength increasing in weak body and strength decreasing in strong body. The weakly consolidated soft rock and coal cementation exhibit significant strain softening behavior and bear compound tension-shear failure under uni-axial compression. With the increase of confining pressure, the tensile failure disappears from the model, and the failure type of composed model changes to local shear failure with different number of shearing bands and plastic failure zones. This work shows important guiding significance for the mechanism study of seismic, rock burst, and coal bump. 展开更多
关键词 three-body model composed of rock and coal strength near strong-weak interface local shear band plastic failure zone
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CAVITATED BIFURCATION FOR COMPOSED COMPRESSIBLE HYPER-ELASTIC MATERIALS 被引量:16
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作者 Ren Jiusheng Cheng Changjun 《Acta Mechanica Solida Sinica》 SCIE EI 2002年第3期208-213,共6页
The cavitated bifurcation problem in a solid sphere composed oftwo compressible hyper-elas- tic materials is examined. Thebifurcation solution for the composed sphere under a uniform radialtensile boundary dead-load i... The cavitated bifurcation problem in a solid sphere composed oftwo compressible hyper-elas- tic materials is examined. Thebifurcation solution for the composed sphere under a uniform radialtensile boundary dead-load is obtained. The bifurcation curves andthe stress contributions subsequent to the cavita- tion are given.The right and left bifurcation as well as the catastrophe andconcentration of stresses are ana- lyzed. The stability of solutionsis discussed through an energy comparison. 展开更多
关键词 composed compressible hyper-elastic material void bifurcation catastropheand concentra- tion of stress energy comparion
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LINEAR SINGULAR INTEGRAL EQUATION ON DOMAINS COMPOSED BY BALLS 被引量:3
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作者 黄玉笙 林良裕 《Acta Mathematica Scientia》 SCIE CSCD 2006年第1期145-151,共7页
For domains composed by balls in C^n, this paper studies the boundary behaviour of Cauchy type integrals with discrete holomorphic kernels and the corresponding linear singular integral equation on each piece of smoot... For domains composed by balls in C^n, this paper studies the boundary behaviour of Cauchy type integrals with discrete holomorphic kernels and the corresponding linear singular integral equation on each piece of smooth lower dimensional edges on the boundary of the domain. 展开更多
关键词 Domains composed by balls discrete kernel linear singular integral equation
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A Composed Protocol of Quantum Identity Authentication Plus Quantum Key Distribution Based on Squeezed States 被引量:2
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作者 张盛 王剑 +1 位作者 唐朝京 张权 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第8期268-272,共5页
It is established that a single quantum cryptography protocol usually cooperates with other cryptographicsystems,such as an authentication system,in the real world.However,few protocols have been proposed on how tocom... It is established that a single quantum cryptography protocol usually cooperates with other cryptographicsystems,such as an authentication system,in the real world.However,few protocols have been proposed on how tocombine two or more quantum protocols.To fill this gap,we propose a composed quantum protocol,containing bothquantum identity authentication and quantum key distribution,using squeezed states.Hence,not only the identity canbe verified,but also a new private key can be generated by our new protocol.We also analyze the security under anoptimal attack,and the efficiency,which is defined by the threshold of the tolerant error rate,using Gaussian errorfunction. 展开更多
关键词 quantum key distribution quantum cryptography composed protocol
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Hadoop-Based Similarity Computation System for Composed Documents 被引量:1
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作者 Xiaoming Zhang Zhipeng Qin +3 位作者 Xuwei Liu Qianyun Hou Baishuang Zhang Jie Wu 《Journal of Computer and Communications》 2015年第5期196-202,共7页
There exist a large number of composed documents in universities in the teaching process. Most of them are required to check the similarity for validation. A kind of similarity computation system is constructed for co... There exist a large number of composed documents in universities in the teaching process. Most of them are required to check the similarity for validation. A kind of similarity computation system is constructed for composed documents with images and text information. Firstly, each document is split and outputs two parts as images and text information. Then, these documents are compared by computing the similarities of images and text contents independently. Through Hadoop system, the text contents are easily and quickly separated. Experimental results show that the proposed system is efficient and practical. 展开更多
关键词 SIMILARITY COMPUTATION composed DOCUMENTS Map REDUCE SYSTEM Integration
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A Method of Computer Simulation for Derivative Weave and Composed Weave 被引量:2
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作者 陈俊琰 汪军 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期97-100,共4页
In this paper, we investigate the method of computer simulation for derivative weave by adopting the way of weave differentiation with mathematical function. And on that base, we explore the way for dealing with compo... In this paper, we investigate the method of computer simulation for derivative weave by adopting the way of weave differentiation with mathematical function. And on that base, we explore the way for dealing with composed weave. It is purposed for building a simple and efficient way of computer simulation for weave. 展开更多
关键词 derivative weave composed weave weave differentiation computer simulation.
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Properties of Sensitive Materials Mainly Composed of ZnO 被引量:1
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作者 Mengkui WANG, Xiao’an YANG and Fuzhong WANG (Department of Physics, Jinzhou Teachers College, Jinzhou 121003, China) Ke SUN (Department of Physics, Northeastern University, Shenyang 110006, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期204-204,共1页
Sensitive materials mainly composed of ZnO and their multi-functional properties were investigated. The temperature extent of linear resistance, non-linear deviation and endurance ability of surge energy were further ... Sensitive materials mainly composed of ZnO and their multi-functional properties were investigated. The temperature extent of linear resistance, non-linear deviation and endurance ability of surge energy were further discussed. The effect of Mg^2+, AI^3+ and Si^4+, which could be solid solutioned in ZnO grain and the function of Y^3+ ion segregated out in grain boundary were studied as well. The function of Ti was analyzed emphatically. 展开更多
关键词 Properties of Sensitive Materials Mainly composed of ZnO
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DYNAMICAL FORMATION OF CAVITY IN A COMPOSED HYPER-ELASTIC SPHERE
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作者 任九生 程昌钧 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第11期1220-1227,共8页
The dynamical formation of cavity in a hyper_elastic sphere composed of two materials with the incompressible strain energy function, subjected to a suddenly applied uniform radial tensile boundary dead_load, was stud... The dynamical formation of cavity in a hyper_elastic sphere composed of two materials with the incompressible strain energy function, subjected to a suddenly applied uniform radial tensile boundary dead_load, was studied following the theory of finite deformation dynamics. Besides a trivial solution corresponding to the homogeneous static state, a cavity forms at the center of the sphere when the tensile load is larger than its critical value. An exact differential relation between the cavity radius and the tensile land was obtained. It is proved that the evolution of cavity radius with time displays nonlinear periodic oscillations. The phase diagram for oscillation, the maximum amplitude, the approximate period and the critical load were all discussed. 展开更多
关键词 composed incompressible hyper-elastic material finite deformation dynamics cavity formation nonlinear periodic oscillation
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Surface Plasmon Interference Lithography Assisted by a Fabry-Perot Cavity Composed of Subwavelength Metal Grating and Thin Metal Film 被引量:1
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作者 梁慧敏 王景全 +1 位作者 王学 王桂梅 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第10期51-54,共4页
A surface plasmon interference lithography assisted by a Fabry-Perot (F-P) cavity composed of subwavelength metal gratings and a thin metal fihn is proposed to fabricate high-quality nanopatterns. The calculated res... A surface plasmon interference lithography assisted by a Fabry-Perot (F-P) cavity composed of subwavelength metal gratings and a thin metal fihn is proposed to fabricate high-quality nanopatterns. The calculated results indicate that uniform straight interference fringes with high contrast and high electric-field intensity are formed in the resist under the F-P cavity. The analyses of spatial frequency spectra illuminate the physical mechanism of the formation for the interference fringes. The influence of the F-P cavity spacing is discussed in detail. Moreover, the error analyses reveal that all parameters except the metal grating period in this scheme can bear large tolerances for the device fabrication. 展开更多
关键词 Surface Plasmon Interference Lithography Assisted by a Fabry-Perot Cavity composed of Subwavelength Metal Grating and Thin Metal Film
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DYNAMICAL FORMATION OF CAVITY FOR COMPOSED THERMAL HYPERELASTIC SPHERES IN NONUNIFORM TEMPERATURE FIELDS
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作者 程昌钧 梅波 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第4期443-452,共10页
Dynamical formation and growth of compressible thermal-hyperelastic Gent-Thomas cavity in a sphere composed of two inmaterials were discussed under the case of a non-uniform temperature field and the surface dead load... Dynamical formation and growth of compressible thermal-hyperelastic Gent-Thomas cavity in a sphere composed of two inmaterials were discussed under the case of a non-uniform temperature field and the surface dead loading. The mathematical model was first presented based on the dynamical theory of finite deformations. An exact differential relation between the void radius and surface load was obtained by using the variable transformation method. By numerical computation, critical loads and cavitation growth curves were obtained for different temperatures. The influence of the temperature and material parameters of the composed sphere on the void formation and growth was considered and compared with those for static analysis. The results show that the cavity occurs stiddenly with a finite radius and its evolvement with time displays a non-linear periodic vibration and that the critical load decreases with the increase of temperature and also the dynamical critical load is lower than the static critical load under the same conditions. 展开更多
关键词 composed thermal-hyperelastic sphere non-uniform temperature field dynamical formation and growth of cavity nonlinear periodic vibration influence of temperature
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The Challenges of Designing a Wooden Beam of Composed Section
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作者 Aiexandre de Macedo Wahrhaftig Ricardo Femandes Carvalho 《Journal of Civil Engineering and Architecture》 2016年第4期430-438,共9页
This work describes details about the challenges and solutions encountered in the timber structure beam. The choice for wood is due to the fact that it is a better material suited for environments with high salinity a... This work describes details about the challenges and solutions encountered in the timber structure beam. The choice for wood is due to the fact that it is a better material suited for environments with high salinity and, in this context, to reduce maintenance costs. The entire roof was supported only by four columns, which forced the side and frontal beams to exceed spans over 18 meters without intermediate supports. This was the most important challenge of the project: to find a section to the beam which can attend the ultimate limit state and serviceability in wood to the dimensions in project. The answer was clear: It would need to have composed section. A computational model was constructed using the finite element method in order to obtain the efforts on the structural elements. It is important to emphasize that the design of a wood structure requires not only knowledge, but creativity as well, to overcome the challenges posed by the distinctive needs to the detailing of this material. In addition to that, it requires special attention during the construction execution, because of the difficulty that the carpenters have to read the specific plans. 展开更多
关键词 composed section wooden structures design finite element method conditions of execution.
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数字人文视域下20世纪留美作曲家社会网络关系分析
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作者 王丽华 余孟 +1 位作者 王扣 刘洁 《山东图书馆学刊》 2024年第3期1-8,共8页
20世纪留美作曲家群体为近现代以来中国音乐的发展做出了不可替代的贡献。文章从数字人文角度出发,梳理多方数据来源,利用社会网络分析软件Ucinet构建20世纪留美作曲家群体社会关系网络,计算网络特征指标,并从师承关系、校友关系、同乡... 20世纪留美作曲家群体为近现代以来中国音乐的发展做出了不可替代的贡献。文章从数字人文角度出发,梳理多方数据来源,利用社会网络分析软件Ucinet构建20世纪留美作曲家群体社会关系网络,计算网络特征指标,并从师承关系、校友关系、同乡关系三个方面剖析了留美作曲家社会网络关系,具有多重发现,为中国近代音乐史、留学史以及作曲家群体研究提供了新的视角与方法。 展开更多
关键词 数字人文 留美作曲家 社会网络分析 关系网络
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柴油烃组成结构对蒸汽裂解性能的影响
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作者 王娟 仵春祺 倪晓晶 《分析仪器》 CAS 2024年第4期79-82,共4页
为了拓宽化工原料及实现柴油的优化利用,开展了不同工艺、不同组成柴油的蒸汽裂解性能评价,采用SPYRO模拟软件对6种柴油进行了模拟计算并对其裂解产物收率进行了对比分析。结合全二维气相色谱-飞行时间质谱和核磁共振技术,从柴油裂解产... 为了拓宽化工原料及实现柴油的优化利用,开展了不同工艺、不同组成柴油的蒸汽裂解性能评价,采用SPYRO模拟软件对6种柴油进行了模拟计算并对其裂解产物收率进行了对比分析。结合全二维气相色谱-飞行时间质谱和核磁共振技术,从柴油裂解产物收率、组成结构及混合裂解性能等方面分析了造成柴油裂解产物分布和收率的差异原因。结果表明:烷烃含量高、馏程窄、碳链短、芳环取代度较高,烷链支化度较低的柴油比较适合作乙烯裂解原料,同时通过与尾油混合裂解,可以进一步优化柴油的裂解性能,为化工行业提供更多元化的原料选择。 展开更多
关键词 柴油 尾油 汽裂解 组成 乙烯收率
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明清时期燕乐调名实质的改变
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作者 杨善武 《南京艺术学院学报(音乐与表演版)》 北大核心 2024年第4期1-5,I0002,共6页
元代以后南北曲所用燕乐调在调名上与宋代是一致的,但其用于表明某种调高、调式的实质作用却在明初以后开始改变。到了清代同样的燕乐调,其宫调含义已然失去,成了徒有虚名的存在。之所以如此,与文人曲词创作由注重音乐的依腔填词而为脱... 元代以后南北曲所用燕乐调在调名上与宋代是一致的,但其用于表明某种调高、调式的实质作用却在明初以后开始改变。到了清代同样的燕乐调,其宫调含义已然失去,成了徒有虚名的存在。之所以如此,与文人曲词创作由注重音乐的依腔填词而为脱离音乐的依律填词有关,其根本原因在于元明清时期以戏曲为主流的民间俗乐发展的要求。正是在俗乐发展的推动下和其他因素的影响下,随着燕乐调名实质的改变,已有燕乐调终被后世广泛采用的工尺七调所代替。 展开更多
关键词 明清时期 燕乐调 调名实质 曲词创作 俗乐发展
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铸牢中华民族共同体意识下电子管风琴创编教学实践研究——以新疆艺术学院为例
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作者 苏媛 《新疆艺术学院学报》 2024年第2期117-124,共8页
随着社会主义文化自信的深入推进,电子管风琴因其独特艺术魅力与文化传承价值,成为铸牢中华民族共同体意识的有效途径之一。本文旨在探讨电子管风琴创编教学在强化民族共同体意识中的作用和意义,采用案例分析与教学实践相结合的方式,针... 随着社会主义文化自信的深入推进,电子管风琴因其独特艺术魅力与文化传承价值,成为铸牢中华民族共同体意识的有效途径之一。本文旨在探讨电子管风琴创编教学在强化民族共同体意识中的作用和意义,采用案例分析与教学实践相结合的方式,针对当前电子管风琴在教学中存在的问题,提出一些创新的教学模式和策略。本文的研究成果为电子管风琴创编教学内容提供了一些新的思路和方法,对铸牢中华民族共同体意识下的民族品质教育具有实践价值。 展开更多
关键词 中华民族共同体意识 电子管风琴 创编教学 文化自觉 教学模式
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基于Symphony DCS Composer组态语言与C语言联合编程的在线性能计算 被引量:2
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作者 方彦军 罗坤 +2 位作者 熊扬恒 阚伟民 郑李坤 《热力发电》 CAS 北大核心 2011年第9期21-25,共5页
提出了1种采用美国ABB公司的Symphony DCS Composer组态语言与C语言联合编程的方法,采用C语言编制在线性能计算程序,Composer组态语言调用C语言程序,将DCS实时数据作为计算数据,计算得到单元机组能耗特性。C语言程序包含了基于IAPWS-IF9... 提出了1种采用美国ABB公司的Symphony DCS Composer组态语言与C语言联合编程的方法,采用C语言编制在线性能计算程序,Composer组态语言调用C语言程序,将DCS实时数据作为计算数据,计算得到单元机组能耗特性。C语言程序包含了基于IAPWS-IF97公式的焓熵值计算程序,集成一体化计算环境,无需调用其它程序,解决了DCS组态语言存在的对于复杂算法的局限性,实现了机组的在线性能计算。以某电厂1台660 MW机组为研究对象,对机组660 MW负荷下的煤耗进行了计算,计算结果误差在允许范围内,表明该在线计算方法可行。 展开更多
关键词 在线性能计算 composER 组态语言 C语言 联合编程 SYMPHONY DCS
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GCMS结合Compound Composer软件筛选PM2.5中有机污染物 被引量:3
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作者 马英歌 戴海夏 +5 位作者 李莉 陈长虹 孙谦 范军 李月琪 黄涛宏 《环境化学》 CAS CSCD 北大核心 2018年第1期188-191,共4页
本文采用高压溶剂萃取(HPSE)方式萃取PM_2.5滤膜中的有机污染物,以气相色谱-质谱(GCMS)和Compound Composer软件进行筛查和半定量计算,同时以已知浓度的农药标样对Compound Composer软件的定性及半定量结果进行验证.结果表明,对1.0μg&#... 本文采用高压溶剂萃取(HPSE)方式萃取PM_2.5滤膜中的有机污染物,以气相色谱-质谱(GCMS)和Compound Composer软件进行筛查和半定量计算,同时以已知浓度的农药标样对Compound Composer软件的定性及半定量结果进行验证.结果表明,对1.0μg·L^(-1)的24种农药混标进行半定量分析,结果偏差在-0.707—0.643μg之间,相对误差在-70.74%—64.31%之间满足日常环境监测的要求.在无标样的情况下,对某地区不同时间的3个PM_2.5样品进行监测,筛查其中主要的有机污染物,并进行半定量计算,可及时掌握大气污染现状,为环境管理和来源解析提供有效数据. 展开更多
关键词 GCMS Compound composER 高压溶剂萃取(HPSE) PM2.5 有机污染物.
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基于3DVIA Composer的家具虚拟展示与设计 被引量:3
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作者 冯力 张荣强 +1 位作者 吴鲁敬 肖畅 《家具》 2017年第2期68-73,共6页
本文旨在利用3DVIA Composer软件进行家具产品的外观及结构装配,实现对家具观看方式和细节交互的虚拟展示。其中,基础动画、关键帧设置、引导标签、文本属性链接是实现虚拟展示及交互技术的关键。通过对床头柜虚拟展示及交互技术的研究... 本文旨在利用3DVIA Composer软件进行家具产品的外观及结构装配,实现对家具观看方式和细节交互的虚拟展示。其中,基础动画、关键帧设置、引导标签、文本属性链接是实现虚拟展示及交互技术的关键。通过对床头柜虚拟展示及交互技术的研究,制作用户的产品文档,将家具产品的信息更好地传达给客户,增强客户对家具产品的认知和体验效果,既减少了设计的成本,又可缩短产品的开发周期。 展开更多
关键词 虚拟展示 交互设计 3DVIA composER 家具
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大丝束碳纤维束内横向动态渗透率计算方法及数值验证
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作者 翟孟雷 陈文广 +4 位作者 黄明 雷金宇 张娜 刘春太 高国利 《中国塑料》 CAS CSCD 北大核心 2024年第9期54-59,共6页
针对现有理论方法无法体现纤维浸润性对渗透率影响的局限性,推导了纤维丝束浸渍过程的毛细压力解析表达式和横向动态渗透率计算公式。采用相场法开展了树脂浸渍纤维丝束过程的数值模拟。结果表明,相场法得到的毛细压力数值解与本文的解... 针对现有理论方法无法体现纤维浸润性对渗透率影响的局限性,推导了纤维丝束浸渍过程的毛细压力解析表达式和横向动态渗透率计算公式。采用相场法开展了树脂浸渍纤维丝束过程的数值模拟。结果表明,相场法得到的毛细压力数值解与本文的解析解总体趋势一致且相差较小,证明了本文方法计算毛细压力的可靠性。并开展了纤维体积分数和接触角对动态渗透率的影响研究,结果表明,本文方法能较好地表征纤维浸润性对渗透率的影响,实现了对不同浸渍半径处渗透率的动态预测。相较于现有的渗透率计算方法,本文方法适用性更强、计算结果更为准确。 展开更多
关键词 毛细现象 树脂流动 动态渗透率 数值模拟 复合材料
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基于CATIA Composer的飞机部件装配进度三维可视化技术研究 被引量:4
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作者 韩志仁 刘小诵 +1 位作者 吴蒙 刘宝明 《航空制造技术》 CSCD 北大核心 2022年第9期89-95,共7页
为了解决实际生产现场中装配状态信息反馈不直观的问题,便于管理和避免差错,确保进度目标的实现,从将装配进度三维可视化展现角度出发,提出了利用CATIA Composer软件搭建飞机部件装配状态三维展示平台方法,研究了基于三维AO和MES系统的... 为了解决实际生产现场中装配状态信息反馈不直观的问题,便于管理和避免差错,确保进度目标的实现,从将装配进度三维可视化展现角度出发,提出了利用CATIA Composer软件搭建飞机部件装配状态三维展示平台方法,研究了基于三维AO和MES系统的零件装配状态获取逻辑,建立了零组件装配状态信息模型,提出了根据零件装配状态驱动三维模型显示方法,阐述了基于实时生产信息的飞机部件装配进度展示过程,并通过某飞机中央翼装配车间实例进行应用验证,证明该方法可行。 展开更多
关键词 CATIA composer 飞机装配进度 轻量化模型 三维可视化 生产管控
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