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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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Comparison of performance between bipolar and unipolar double-frequency sinusoidal pulse width modulation in a digitally controlled H-bridge inverter system
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作者 雷博 肖国春 吴旋律 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期277-284,共8页
By deriving the discrete-time models of a digitally controlled H-bridge inverter system modulated by bipolar sinu- soidal pulse width modulation (BSPWM) and unipolar double-frequency sinusoidal pulse width modulati... By deriving the discrete-time models of a digitally controlled H-bridge inverter system modulated by bipolar sinu- soidal pulse width modulation (BSPWM) and unipolar double-frequency sinusoidal pulse width modulation (UDFSPWM) respectively, the performances of the two modulation strategies are analyzed in detail. The circuit parameters, used in this paper, are fixed. When the systems, modulated by BSPWM and UDFSPWM, have the same switching frequency, the stabil- ity boundaries of the two systems are the same. However, when the equivalent switching frequencies of the two systems are the same, the BSPWM modulated system is more stable than the UDFSPWM modulated system. In addition, a convenient method of establishing the discrete-time model of piecewise smooth system is presented. Finally, the analytical results are confirmed by circuit simulations and experimental measurements. 展开更多
关键词 bipolar sinusoidal pulse width modulation (SPWM) unipolar double-frequency SPWM H-bridgeinverter discrete-time model
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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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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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基于3DVIA Composer的产品虚拟展示与设计 被引量:11
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作者 金照 黄琼涛 张荣强 《机械设计》 CSCD 北大核心 2015年第11期119-122,共4页
在工业设计领域中,虚拟展示技术使人们可看到产品实时动态的三维展示,感受到与产品交互的体验,克服传统表达方式中静态的、文本的、二维图像等信息不足的缺陷。在3DVIA Composer软件环境下,建立产品外观及结构装配,实现观看方式和细节... 在工业设计领域中,虚拟展示技术使人们可看到产品实时动态的三维展示,感受到与产品交互的体验,克服传统表达方式中静态的、文本的、二维图像等信息不足的缺陷。在3DVIA Composer软件环境下,建立产品外观及结构装配,实现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。通过对多轴飞行器进行虚拟展示与交互技术研究,制作用户的产品文档,可准确了解客户需求,节约时间和成本,增强产品认知与体验的效果。 展开更多
关键词 计算机辅助设计 产品虚拟展示 3DVIA composER 多轴飞行器
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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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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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Compound composer软件系统在水体有机污染物筛查中的应用 被引量:2
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作者 胡雅琴 史绵红 +2 位作者 杨晓冉 张付海 张敏 《环境科学导刊》 2015年第2期120-124,共5页
通过系列监测活动考察并验证了Compound composer软件系统在水体有机污染物快速定性、半定量工作中的可靠性。对2 mg/L的19种有机氯农药的标准溶液可以实现完全分离与准确定性,半定量结果的相对误差在-94%~42%;进一步利用该软件系统筛... 通过系列监测活动考察并验证了Compound composer软件系统在水体有机污染物快速定性、半定量工作中的可靠性。对2 mg/L的19种有机氯农药的标准溶液可以实现完全分离与准确定性,半定量结果的相对误差在-94%~42%;进一步利用该软件系统筛查某湖泊4条支流,共筛查出有污染物11种,除常见的钛酸酯类外,还检出苯并噻唑、2-苯氧基乙醇、甲硫基苯并噻唑、碳氢化合物和苯并呋喃等;最后还将其用于实际的突发环境应急事故应急监测中,筛查出特征污染物2-甲氧基-6-甲基苯胺,为锁定责任企业和环境执法提供了依据。结果表明,Compound composer软件在缺乏标准溶液的情况下,可以实现有机污染物的快速定性及半定量,尤其在突发环境污染事件中有一定的应用价值。 展开更多
关键词 COMPOUND composER 水体有机物 筛查 应用
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基于3DVIA Composer 3D动画在机床夹具CAI中的应用研究 被引量:2
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作者 牛鹏辉 刘救世 李大磊 《科教导刊》 2017年第12期32-33,共2页
文章简述了动画是现代化的教学模式CAI的主要手段,在课堂教学中起着不可缺少的重要作用,分析了动画在课堂教学中的作用机理,根据机床夹具设计课程实践性强的特点,论述了将3D动画软件3DVIA Composer应用于课堂教学的必要性,介绍了应用该... 文章简述了动画是现代化的教学模式CAI的主要手段,在课堂教学中起着不可缺少的重要作用,分析了动画在课堂教学中的作用机理,根据机床夹具设计课程实践性强的特点,论述了将3D动画软件3DVIA Composer应用于课堂教学的必要性,介绍了应用该软件制作3D画的一般方法和步骤,对基于3DVIA Composer的动画在机床夹具CAI中的教学实践和效果进行了总结。 展开更多
关键词 3DVIA composER CAI 3D动画 机床夹具
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基于3DVIA Composer的三维装配作业指导书编制技术研究 被引量:4
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作者 郭具涛 张小龙 +1 位作者 付少龙 冯波 《CAD/CAM与制造业信息化》 2014年第5期51-54,共4页
随着数字化技术的发展,装配工艺三维化成为一种必然趋势。利用3DVIA Composer软件直接依据产品MBD数模,通过工艺图解编制和装配动画制作能够方便、快捷地进行三维装配作业指导书的制作,并能够将三维工艺发布到装配现场指导车间工人完成... 随着数字化技术的发展,装配工艺三维化成为一种必然趋势。利用3DVIA Composer软件直接依据产品MBD数模,通过工艺图解编制和装配动画制作能够方便、快捷地进行三维装配作业指导书的制作,并能够将三维工艺发布到装配现场指导车间工人完成产品装配。 展开更多
关键词 三维装配 作业指导书 composER 编制技术 装配工艺 动画制作 产品装配 数字化技术
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