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1.
柔性制造系统DNC控制过程分析   总被引:3,自引:0,他引:3  
群控(DNC)是柔性制造系统(FMS)控制的一个重要组成部分,本文详细介绍和分析了我校CIM中心的FMS示范系统的DNC控制过程。主要内容包括FMS示范系统简介、DNC模块的主要功能和结构、DNC模块中的通讯实现过程。它提供了一种可行的、适应于不同数控系统的DNC实施方案,适合各种FMS系统中的DNC控制,并有利于FMS系统的扩展。  相似文献   

2.
ESTABLISHMENTANDAPPLICATIONSOFMATHEMATICALMODELSFORCONCENTRATIONDISTRIBUTIONINMo-Fe-Ni-CoDIFFUSIONQUARTERNARY──(Ⅱ)Characteris...  相似文献   

3.
基于产品数据管理的SBW—CIMS信息集成技术   总被引:2,自引:0,他引:2  
产品数据管理(PDM)集成并管理与产品有关的信息,过程及人与组织,它以软件为基础,是一门管理所有与产品有在的信息和过程的技术。本文以上海鼓风机厂CIMS应用工程(SBW_CIMS)为背景,详细地讨论了以PDMO 集成平台的信息集成方法。  相似文献   

4.
ESTABLISHMENTANDAPPLICATIONSOFMATHEMATICALMODELSFORCONCENTRATIONDISTRIBUTIONSINMo-Fe-Ni-CoDIFFUSIONQUARTERNARY(Ⅰ)Establishmen...  相似文献   

5.
IMPROVEMENTINELECTROCHEMICALPERFORMANCESOFMm(NiCoMnAl)5ELECTRODESBYSURFACEMODIFICATION①ChenWeixiangDepartmentofMaterialsScien...  相似文献   

6.
COMPOSITIONANDSPECTROSCOPICSTUDIESOFHYDRATEDSODIUMALUMINATECOMPOUNDSQIUGuofang,DENGHongmei,ZENGWenmingandCHENHianyi(ShanghaiI...  相似文献   

7.
《钢管》1994,(3)
河北省金属学会组织召开第四届钢管(无缝、焊接)学术会议4THSEMINARONSTEEL(SEALMLESS&WELDED)TUBES&PIPESHELDBYHEBEIPROVINCIALSOCIETYOFMETALS由河北省钢管学术委员会和省冶金行...  相似文献   

8.
MORPHOLOGYANDORIENTATIONCHARACTERISTICSOFDIRECTIONALLYSOLIDIFIEDα(A1)-Mg_2SiEUTECTIC¥S.P.Li;S.X.Zhao;M.XPan;D.Q.Zhao;andX.C.C?..  相似文献   

9.
THEORETICALANALYSISANDDESIGN/CALCULATION FORMULAEFOR HYDRAULICIMPACTMECHANISMHe;Qinghua(DepartmentofMechanicalEngineering,Cen...  相似文献   

10.
ANALYSESOFENERGYLOSSESANDACCUMULATORANDPARAMETERSDESIGNMETHODOFHYDRAULICIMPACTORMECHANISM¥He,Qinghua(DepartmentofMechanicalEn...  相似文献   

11.
Ni—Zr二元相图计算   总被引:2,自引:0,他引:2  
优化和计算了NiZr二元相图。液相用缔合物模型、端际固溶体用替换溶液模型描述,Ni5Zr和Ni10Zr7则分别选用了(Ni)1(Ni,Va)4(Ni,Zr)1和(Ni,Zr)10Zr7的亚点阵模型。计算结果与大部分相图和热力学数据相吻合  相似文献   

12.
To achieve a high productivity and low costs in modern steelmaking, for example, oxygen top blow,bottom blow and combined processes, the following problems have been discussed in detail: (1) Sampling problems (data aquisition, precision, reliability); (2) Process problems (mostly of metallurgical and technological kind); (3) Method specific problems (choice of the analysis method).  相似文献   

13.
14.
ABSTRACT

We present a system-level connectionist model of pupil control that includes brain regions believed to influence the size of the pupil. It includes parts of the sympathetic and parasympathetic nervous system together with the hypothalamus, amygdala, locus coeruleus, and cerebellum. Computer simulations show that the model is able to reproduce a number of important aspects of how the pupil reacts to different stimuli: (1) It reproduces the characteristic shape and latency of the light-reflex. (2) It elicits pupil dilation as a response to novel stimuli. (3) It produces pupil dilation when shown emotionally charged stimuli, and can be trained to respond to initially neutral stimuli through classical conditioning. (4) The model can learn to expect light changes for particular stimuli, such as images of the sun, and produces a “light-response” to such stimuli even when there is no change in light intensity. (5) It also reproduces the fear-inhibited light reflex effect where reactions to light increase is weaker after presentation of a conditioned stimulus that predicts punishment.  相似文献   

15.
基于灰色预测模型电火花线切割工艺参数优化   总被引:1,自引:0,他引:1  
针对电火花线切割加工机制的不确定性,工艺参数与工艺指标具有高度非线性关系;设计正交实验,分析脉宽、占空比、加工电流、丝速和跟踪系数对SKD?11材料去除率( MRR)的影响;分别建立逐次广义回归模型( GRM)和灰色预测模型( GFM),并对两个模型进行实验验证和比较,寻求出最佳的工艺参数。验证实验表明,所建立的灰色预测模型( GFM)能够对实际加工的材料去除率( MRR)进行精确的预测。  相似文献   

16.
An approximate calculation of the exchange interaction constant JRT between the rare-earth sublattice and the transition metal sublattice in R2Fe17-xAlx (R=Tb, Gd, and Dy) compounds is given by the molecular-field model and the results of neutron diffraction. The calculated values, -JR,T/k, for Dy2Fe17-xAlx (x=5, 6, 7 and 8), Tb2Fe10Al7, Gd2Fe17-xAlx (x = 7, 8) compounds are 8.62K, 8.64K, 9.52K, 10.34K and 10.66K, 10.65K, and 9.85K, respectively, they are in agreement with the experimental values, -JR,T/k, of Dy2Fe17-xAlx (x=5, 6, 7 and 8), Tb2Fe10Al7 and Gd2Fe17-xAlx (x=7, 8) compounds, which are 8.77K, 9.25K, 10.1K, 10.9K and 10.35K, 10.1K, and 10.3K, respectively. The origins of the difference between the calculated and the experimental results are discussed.  相似文献   

17.
A simple Eulerian thermomechanical modeling of friction stir welding   总被引:2,自引:0,他引:2  
A simple three-dimensional thermomechanical model for friction stir welding (FSW) is presented. It is developed from the model proposed by Heurtier et al. (2006) based on a combination of fluid mechanics numerical and analytical velocity fields. Those velocity fields are introduced in a steady state thermal calculation to compute the temperature field during welding. They allow partial sliding between the shoulder and the workpiece, the amount of which is provided as an additional result of the model. The thermal calculation accounts for conduction and convection effects by means of the particular derivative. The complete thermomechanical history of the material during the process can then be accessed by temperature and strain rate contours.The numerical results are compared with a set of experimental test cases carried out on an instrumented laboratory device. The choices for modeling assumptions, especially tribological aspects, are discussed according to agreements or deviations observed between experimental and numerical results. The amount of sliding appears to be significantly influenced by the welding conditions (welding and tool rotational velocities), and physical interpretations are proposed for its evolution.  相似文献   

18.
The grain size in the heat-affected zone (HAZ) of workpieces is an important factor for evaluating the welding quality. The Monte Carlo technique of grain growth in the heat-affected zone of alloy is widely used. A finite element model (FEM) was employed to simulate the temperature field of gas metal arc welding (GMAW) ; the data of thermal cycles were used in the Monte Carlo model to calculate the grain sizes in different welding heat inputs. The equation for the relationship between Monte Carlo Step and real time has been estimated using regression analysis. Then mathematics model of the grain growth could be worked out by both the kinetic model and the Monte Carlo model. The dynamic process of grain growth was simulated by the result of the Monte Carlo model. The experimental result was used to prove the validity of this method in simulating of microstructure.  相似文献   

19.
为了预测Al/Mg基纳米复合材料的高温流变行为,在不同的应变速率(0.01-1.0s-)和温度(523,623和1723K)的条件下进行热压缩试验,利用所得到的应力-应变数据,开发了本构模型,比如一般流动方程。阿累尼乌斯双曲模型、Johnson-Cook(JC)和改性的Zerilli-Armstrong(ZA)模型及人工神经网络(ANN)模型。通过使用统计参数,例如均方根误差(RMSE)、回归系数(R2)、平均相对误差(MRE)和分散指数(Is),比较了人工神经网络和不同的本构模型。结果表明,人工神经网络模型对AA5083-2%TiC复合材料的热变形流动应力的评估准确性更高。  相似文献   

20.
院校研究有两种研究路向,一种是“(问题)一理论—假设—观察一理论一(问题)”的研究路径,另一种是“(问题)一观察一概括一理论—观察一(问题)”的研究路径。从哲学方法论层面看,院校研究主要有四种研究范式,即经验主义、实证主义、结构主义和人本主义。其中,实证主义和经验主义是定量研究的方法论基础,结构主义与人本主义是定性研究的方法论基础。定性研究与定量研究并不是绝对的两分,它们构成一个连续的系谱。实验法与文学法位于这一系谱的两个极端。  相似文献   

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