共查询到20条相似文献,搜索用时 65 毫秒
1.
本文论述了CAX系统间数据交换的专用文件接口(STL)、中性文件接口(NFI)和共享数据集成(SDBI)方式的实现机制及其优缺点,为CAX系统间的集成打下了基础提供了保障。 相似文献
2.
姜燕 《仪器仪表与分析监测》1998,(1):1-7
液相色谱—气相色谱联用技术的发展姜燕(山西经济管理学院城建系太原030006)关键词液相色谱毛细管气相色谱联用接口液相色谱和气相色谱联用技术(LC/GC)是一项新型多维色谱技术[1]。它兼有LC的高选择性和GC的高效率及高灵敏度,对复杂有机试样有较强... 相似文献
3.
CHINESE JOURNAL OF MECHANICAL ENGINEERING 总被引:1,自引:0,他引:1
《机械工程学报(英文版)》1994,(3)
CHINESEJOURNALOFMECHANICALENGINEERINGCHINESEJOURNALOFMECHANICALENGINEERING(EnglishEdition)(Quarterly)(Startedin1988)Volume7No... 相似文献
4.
《仪器仪表标准化与计量》2000,(1)
ODVA在欧洲CENELEC向DEVICENET敞开大门现场总线委员会投票接受DeviceNet作为欧洲标准BocaRaton,Fla.2000年1月7日,开放的DeviceNet供应商协会(ODVA)很高兴宣布:经过欧洲电工标准化委员会(CENELEC)成功的投票,DeviceNet被正式采纳作为欧洲标准。新标准名为EN50325,“在基于ISOI1898(CAN)的控制器和设备接口的工业通信子系统中”DeviceNet得到了来自各成员国的压倒多数的支持。根据现场总线委员会的建议,CENELEC… 相似文献
5.
数控特征单元定义、实现及其应用研究 总被引:1,自引:0,他引:1
从产品信息集成和分布式计算的角度提出了数控特征单元(NCFU)的概念。通过利用UCFU技术,可以实现基于特征的NCP/CNC集成与刀具轨迹的动态产生和实时控制。分析了NCFU的功能和信息需求及其定义方法,讨论了适合于2.5轴数控加工的行切特征单元和环切特征单元,以及适合于3轴曲面加工的网格曲面特征单元,并提出了相应的NCFU自动分解算法。对基于NCFU的NCP/CNC集成系统体系结构进行了研究。 相似文献
6.
在T=110~195℃及ε=0.4×10(-3)~2.47×10(-3)S(-1)时对Zn-1.8%Al合金超塑性m-δ曲线进行了测定,属mL=mmin型。可分为基本形式、上升式及下降式三种形式。应用CL(刘勤)方程式对C值进行了计算,获得了全部有关特征参数,包括(δ0=0),δL,δF;m0(≠0),mL,mF;(C0=k0/k0=1),CL(=kL/k0)及CF(=kF/k0)的全部或一部分,由曲线的形式决定。测到的总延伸率δF=190/~410%.各自由每根m-δ曲线的其余特征参数的动静态或直间接效应的综合结果所决定。进一步否定了当前超塑性领域内存在的错误观点。并对有关微观变化进行了初步研究。 相似文献
7.
RESEARCHONCAD/CAMFORHY-DRAULICMANIFOLDBLOCKSRESEARCHONCAD/CAMFORHY-DRAULICMANIFOLDBLOCKSXieLin;DongHua;LiuNenghong;SunQinghua... 相似文献
8.
WEARTRANSITIONSOFC/CuCOMPOSITEMATERIALS¥BuYan;XiangZhongxia(TianjinUniversity)Abstract:AnunlubricatedslidingfrictiontestonC/C... 相似文献
9.
机床数控系统中的早期产品如FANUC7系统等,未提供通用的通讯接口,故要实现与微机的通讯,必须首先解决其通讯接口问题。本文在对FANUC7系统I/O接口分析的基础上,设计了一种实用、方便的CNC软盘程序传送器,可以实现计算机与CNC系统间的程序及其它数据的传输功能。 相似文献
10.
张彦平 《计算机集成制造系统》1996,2(1):27-30
ASWF++(Access Software for Working Form)是为支持CAD/CAM系统内部数据管理而开发的O-O数据存取软件。它采用EXPRESS为其DDL,SDAI为应用程序界面,并提供了与商用DBS集成的统一接口。本文介绍ASWF++的系统结构、主要特点和应用,以及如何利用ASWF++在OODBAS上实现SDAI《 相似文献
11.
Clarence W.DE SILVA 《Instrumentation》2019,(4):72-84
An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t... 相似文献
12.
INTEGRAL EQUATION METHOD'S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES 总被引:1,自引:0,他引:1
LI Cheng ZHENG Yanping 《机械工程学报(英文版)》2008,21(6):115-118
The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value. 相似文献
13.
30 keV Ga+ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z2, and shows a non-monotonic relationship between contrast and Z2. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z2, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory. 相似文献
14.
This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an... 相似文献
15.
分布动态载荷识别的抗噪处理 总被引:2,自引:2,他引:0
针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性. 相似文献
16.
针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。 相似文献
17.
The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar... 相似文献
18.
The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods.... 相似文献
19.
J. A. Williams 《Lubrication Science》1997,3(3):267-306
Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface. 相似文献
20.
M. Stedman 《Journal of microscopy》1988,152(3):611-618
Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space. 相似文献