STEP-NC译码器及其关键技术

为实现与产品模型数据交换标准兼容的数控数据接口在数控系统中的应用,开发了STEP-NC译码器.阐述了译码器的工作原理,将译码器按照逻辑关系分为六个功能模块,介绍了各个模块的功能和实现方法.详细论述了STEP-NC译码器实现中的三项关键技术:类库设计、刀轨规划参数读取方法和STEP-NC坐标系转换.最后,结合一个STEP-NC程序实例,利用所开发的STEP-NC译码器,规划出该程序实例的完整刀具轨迹,通过STEP-NC铣削仿真系统对刀具轨迹及零件模型进行切削仿真.仿真结果表明,所开发的STEP-NC译码器是正确可行的.     

弱对偶基下RS码译码方法的研究

讨论了高速RS码译码器的设计问题.研究了有限域元素在弱对偶基(WDB)下的表示,基于弱对偶基下的最优弱对偶基的计算方法,给出了有限域比特并行乘法器的设计;采用了一种可以避免求逆运算的修正BM迭代算法,并且利用这样的迭代算法和基于弱对偶基的比特并行乘法器构成了广泛应用的RS码的译码器.对译码器定量分析的结果表明:弱对偶基下比特并行乘法器设计复杂度降低,便于VLSI实现;修正BM迭代算法使得简单的硬件实现成为可能,且有利于On-The-Fly纠错.译码器的数据吞吐率可达较高值,有利于高速应用场合.     

基于FPGA的卫星导航信号viterbi译码方法研究

在介绍Xilinx公司FPGA的Viterbi译码器IP核译码模块设计的基础上,分析了广泛应用于卫星导航信号中的卷积编码及viterbi译码过程,重点分析了关键问题,提出了具体模块设计方案,并进行仿真和硬件验证。     

FPGA中宽边译码器的测试方法研究

现有的关于FPGA的测试主要集中在可编程逻辑和互连线资源,而没有涉及FPGA中的宽边译码器的测试。本文提出了一种测试FPGA中宽边译码器的方法,该方法实现了FPGA中的宽边译码器的逻辑资源及其相连的长线资源的全覆盖测试。该实验采用Xilinx公司的XC4000E系列芯片,在基于SOC软硬件协同技术的FPGA自动测试系统中进行测试。实验结果表明,用本文提出的4次配置图形和测试向量能够完成全覆盖测试。     

北京科仪厂两种新产品面市

<正> 北京科学仪器厂研制的TTY-1型通用台式译码器和BK—1型条码扫描光笔,于最近通过技术鉴定。 TTY-1型通用台式译码器主要适用于光笔条形码扫描器;BK-190型条码扫描光笔是一     

正交译码接口电路的原理与设计

介绍了正交译码接口电路的工作原理，分析了数字延迟噪声滤波器、四倍频正交译码器、抑制逻辑等单元逻辑状态，提出了正交译码接口电路在数字闭环运动控制系统和数字数据输入系统的设计方案。     

正确曝光与光敏电阻

本文以摄影技术为例,分析光敏电阻在实际应用中的一些具体技术问题,这些问题对于其它的光电自动控制器,指示器,检测器、显示器、译码器和发生器等也是有益的     

激光全角度扫描条码识读器研究

本文详细讨论了激光全角度扫描条码识读器的关键技术，对光学扫描图案的布局、扫描激光束的空间分布特性、扫描图案的产生、接收系统的渐晕特性和自动增益控制、高速ＤＳＰ芯片实现高速译码器的原理和方法等进行了详细的分析     

基于单片机的多路数据采集系统设计

本系统采用ADuC841单片机作为核心处理器,对32路模拟信号进行数据采集、分析和处理,通过数码管显示所有通道中最大、最小数据的数值和通道号。系统采用单片机、数据选择器、译码器及相关硬件电路进行设计,能对32路模拟数据进行采集,然后根据实际需要由单片机对数据进行实时分析和处理。     

条形码物流管理技术在制造自动化系统(MAS)中的应用

对条形码识别技术的基本概念、在制造自动化系统(MAS)中的应用与实施、编码方案以及条形码物流管理系统的工作原理及运作过程作了详细的论述，并介绍了该系统专用译码器的特点。     

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.     

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.     

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.     

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。     

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.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...