基于Linux的MCX314设备驱动程序设计与实现

介绍一种基于S3C2440的嵌入式Linux扩展运动控制芯片MCX314的设计方法,给出运动控制平台的硬件接口设计方案.着重分析嵌入式Linux下运动控制芯片MCX314设备驱动程序的设计与实现.并在嵌入式GUI解决方案Qtopia的基础上,开发出运动控制系统软件.该系统具有低功耗、低价位、效率高等特点,是经济型数控系统发展的方向.     

基于ARM与FPGA的嵌入式数控系统设计

基于ARM与FPGA设计了嵌入式数控系统.其ARM芯片采用Samsumg公司的基于ARM9的S3C2410,FPGA采用Altera公司的Cyclone系列的EP1C20.介绍了数控系统的硬件设计,并采用LINUX操作系统和NIOS软处理器,着重讨论了硬件的接口设计.     

埃斯顿嵌入式数控系统在三辊卷板机上的解决方案

详细阐述了埃斯顿嵌入式数控系统在三辊卷板机上的应用技术。该控制系统基于DSP技术构建,配置多种硬件端口,内置人机交互子系统和实时控制子系统,可实现高精度运动控制。具体应用包括自动控制预弯长度、自动预弯、自动卷圆、自动保存和调用加工程序,等。     

基于ARM的嵌入式可重构数控系统的设计与实现

本文提出了一种基于ARM嵌入式微处理器和大规模可编程逻辑器件FPGA的数控系统可重构硬件设计方法，并在此基础上，开发了经济型数控系统的原型样机，充分利用ARM微处理器的高速运算能力与FPGA的快速配置能力，大大减少了系统的外围接口器件，有效地降低了系统成本。     

嵌入式超声内圆磨削数控系统的研究与开发

在深入研究嵌入式系统技术和超声振动内圆磨削加工特点的基础上,提出一种基于ARM和μC/OS-Ⅱ的嵌入式超声振动内圆磨削数控系统的设计方案.以高性能、低功耗的32位ARM嵌入式处理器LPC2210为核心,配以系统所需的外围模块和各种接口电路组成系统的硬件结构;以源码公开的μC/OS-Ⅱ实时嵌入式操作系统为核心,开发系统所需的应用软件,将μC/OS -Ⅱ实时嵌入式操作系统扩展为一个完整的、实用的嵌入式超声波内圆磨削数控系统.     

基于FPGA的嵌入式数控系统功能模块设计

将高速、大容量的FPGA应用到基于ARM9的嵌入式数控系统中,实现系统和FPGA的连接和功能控制。基于FPGA的寄存器结构,完成总线接口模块、硬件插补器、一级缓冲模块、定时器模块、手轮脉冲模块、多功能计数模块的设计和部分模块的仿真测试。仿真结果表明所设计功能模块的有效性与适用性,说明将FPGA应用到嵌入式数控系统中大大改善系统的实时性。     

数控系统机床环境仿真仪设计

研制一种可用于华中HNC-21M3铣床数控系统主机调试、仿真运行和故障诊断的电子装置,设计该装置的硬件电路原理和嵌入式程序。装置具有可编程模拟机床环境功能,可以与数控系统主机的主轴、伺服、PLC接口对接,针对数控系统主机进行参数调试、PLC程序调试、仿真运行、故障诊断等操作。     

基于工控机平台的可重构开放式计算机数控系统软件开发

对五轴数控系统的主要任务进行分析及模块划分,开发以运动控制器为下位机,工控机为上位机的嵌入式可重构开放数控系统。对该系统的硬件结构构成、软件结构设计及开发人机界面的关键技术进行阐述。实验证明,该系统完全能满足现代数控机床对开放式数控系统的要求。     

基于PC的全软件雕铣机数控系统设计及实现北大核心

为简化雕铣机数控系统的硬件结构、降低硬件成本、增强可拓展性,基于PC平台提出一种全软件数控系统的设计方案。搭建雕铣机数控平台,构建以Linux+Xenomai双内核实时系统为基础的EtherCAT主站。在Linux域中基于Qt开发数控系统软件,设计UI界面、逻辑处理、运动控制、功能接口等模块;在Xenomai域中基于实时函数库开发硬件驱动程序,设计进程通信模块和定时驱动模块,重点说明采用有限状态机开发的定时驱动模块程序。阐述数控加工工作流程,进行系统性能测试和加工实验。结果表明:该系统实时性强、运行稳定,可满足雕铣机的数控加工要求。     

嵌入式数控系统加工代码三维图形库开发

通过将三维技术应用于嵌入式数控系统,介绍了一种嵌入式数控系统加工代码三维图形库的开发方法。在嵌入式系统中构建基于DLL的图形库平台,介绍了图形库的功能和图形库算法的实现,通过引入嵌入式三维图形应用程序接口OpenGL ES,实现了三维图形库的开发。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

THERMODYNAMICS STUDY ON THE DECOMPOSITION OF CHROMITE WITH KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

INFLUENCE OF HEAT TREATMENT ON DAMPING BEHAVIOUR OF THE MAGNESIUM WROUGHT ALLOY AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.     

Directional Growth of Tin Crystals Controlled by Combined Solute Concentration Gradient Field and Static Magnetic Field

A new method was introduced to achieve directional growth of Sn crystals. Microstructures in liquid(Pb)/liquid(Sn) diffusion couples were investigated under various static magnetic fields. Results show that the β-Sn crystals mainly reveal an irregular dendritic morphology without or with a relatively low static magnetic field(B0.3 T). When the magnetic field is increased to 0.5 T, the β-Sn dendrites close to the final stage of growth begin to show some directional character. With a further increase in the magnetic field to a higher level(0.8–5 T), the β-Sn dendrites have an enhanced directional growth character, but the dendrites show a certain deflection. As the magnetic field is increased to 12 T, the directional growth of the β-Sn dendrites in the center of the couple is severely destroyed. The mechanism of the directional growth of the β-Sn crystals and the deflection of the β-Sn crystals with the application of static magnetic field was tentatively discussed.