空盒气压表检定压力控制器的设计及应用

详细介绍空盒气压表气压示值误差和温度系数的检定过程,分析示值检定箱执行机构的气动工作原理,整理出PLC的控制变量表,并应用PID功能模块实现压力自动调节,空盒气压表检定设备可以实现气压示值和温度系数的自动检定,提高仪表检定、校准的工作效率以及操作准确度,简化计量工作流程,降低工作强度,保障科研生产任务的顺利进行。     

气压仪器检定装置的升级改造

文章针对气压检定装置在使用中存在的一些问题,会同厂家对其进行了升级改造。介绍了改造后的气压检定装置的设计原理、软件和硬件设计以及技术指标等,新装置集成了目前先进的计量设备及技术,编写相应的程序软件升级改造而成。可广泛适用于气象部门空盒气压表、自动站气压传感器以及部分数字压力计的计量检定工作,实现气压检定工作的自动化,提高检定数据的准确性和可靠性,并有效提高检定的工作效率。     

PTB220气压传感器调整方法的补充

此文按照《自动气象站检定规程》介绍的用超级终端对PTB220气压传感器进行数字量调整的方法，选取一台CAWS型自动站气压传感器进行实时调整，通过实验，解决了RS-232串口通信电缆的具体制作方法及《自动气象站检定规程》中没有提到的多点调整时检定结果修正值和初始修正值的叠加问题，从这两个方面对规程中关于PTB220气压传感器的调整进行了补充，使超差的气压传感器误差恢复到允许范围之内，为自动站超差气压传感器的调整提供参考。     

高精度多通道自动气象站气压检定仪的设计

气压检定仪是一种为自动气象站提供标准气压信号的仪器。针对目前气象计量业务应用的检定仪输出气压信号单一不能兼顾不同型号自动站的问题,设计一种高精度、多通道(RS232、模拟电压、触发脉冲)同时输出而互不干扰的新型气压检定仪。采用低功耗单片机为主控、CPLD扩展I/O口的硬件架构。RS232通道气压信号利用单片机的USART编程产生;触发脉冲通道利用CPLD模拟传感器的时序,收到自动站的触发信号后分频产生;模拟电压通道选用高精度DAC和极低失调电压(3μV)运放产生。总线隔离和DC-DC措施保证了各通道互不干扰。测试表明:3个通道输出的气压信号范围均为500~1 100 h Pa,覆盖了自动站的测量范围。最大误差0.02 h Pa,远低于自动站的最大测量误差±0.3 h Pa,为不同型号的自动站提供了一种综合的计量检定仪器。     

一种新型自动气压检定系统

本文论述了采用先进的工业控制技术与独特的箱体结构设计相结合,一种新型气压检定系统和温压联合测试系统,对该系统具有控制精度高,稳定性好、可靠性高、维护简单、操作方便、数据自动处理等特点进行了介绍.     

一种新型自动气压检定系统

本文论述了采用先进的工业控制技术与独特的箱体结构设计相结合，一种新型气压检定系统和温压联合测试系统，对该系统具有控制精度高。稳定性好、可靠性高、维护简单、操作方便、数据自动处理等特点进行了介绍。     

计量管理一体化在温度计自动检定中的应用

一种新的温度计自动检定系统模型,计量管理一体化在温度计自动检定中的应用,使得自动检定系统可以与企业数据库联系起来。     

多功能校准源的数字多用表自动检定系统设计分析

本文主要根据多功能校准源进行分析,探究多功能校准源的数字多用表自动检定系统的设计,对数字多用表自动检定系统的原理、系统的具体组建方式以及数字多用表自动检定系统的操作流程进行简述,为多功能校准源的数字多用表自动检定系统设计提供学术参考。     

一种三维可调式气压驱动的水表自动对中系统设计

针对传统水表检定装置不易调节水表位置和安装低效的不足，提出了一种三维可调式气压驱动水表自动对中系统。系统由固定底板、前后导轨、左右导轨、第一V形槽托盘、第二V形槽托盘和气缸等组成。驱动V形槽托盘，实现水表在左右导轨上的左右滑动；驱动左右导轨，实现水表在前后导轨上的前后滑动；调节气缸分隔板上下两侧的气路气压，可驱动固定底板上下移动，从而调节水表的安装高度。该设计方案实现了水表检定前的左右、前后、上下的三维调节，以便水表快速到达安装位置并完成对中、夹紧、固定等工序；减少了人力输出，提高了检定效率，装表时间从原来的大于5 min降低至1 min以内。     

指针式压力表全自动检定系统的研制

本文介绍了一种指针式压力表全自动检定系统。该系统包括标准压力自动产生系统及仪表示值自动判读系统两部分。该系统检定速度快、检定效率高,可用以检定０～１６ＭＰａ、０．４级以下的压力表。本系统的研制对于改善目前国内压力表检定工作的落后状况,实现压力表检定的自动化具有重要意义。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

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...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

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.     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

Non-monotonic material contrast in scanning ion and scanning electron images

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.     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.