基于FPGA的控制器局部网(CAN)总线控制器设计

提出一种基于FPGA的CAN总线控制器的实现方案,给出其结构框图,并对内部各模块进行较为详细的介绍.最后给出控制器在Altera公司的系列FPGA上实现时的资源利用情况及其性能,并参照CAN协议规范对其进行仿真验证.     

硫化锌衬底上氧化铪保护膜制备及性能研究

采用磁控溅射法在硫化锌衬底上制备了氧化铪薄膜,并对氧化铪薄膜的结构和性能进行了分析和测试.结果表明,制备的氧化铪薄膜结构为单斜相,膜层致密,在8～12 μm波段对硫化锌衬底的透过率没有明显影响,硬度显著高于衬底的硬度,且与衬底结合良好,适合用作硫化锌的红外保护膜.     

基于SOPC的列车环境异物入侵监测系统研究

研究一种基于SOPC技术的列车分布式环境异物入侵监测系统,系统将视频数据的采集、处理与传输集成到单片FPGA上,采集和处理部分用硬件描述语言编写成硬件模块,作为外设挂到NiosⅡ系统中,传输部分采用以太网接口IP核,构建成SOPC系统去实现异物入侵监测系统.同时,用户可以方便地添加IP核来扩展系统功能.最后,在Altera公司的DE2开发平台上进行验证,达到了设计的要求.     

Effect of astrocyte on synchronization of thermosensitive neuron-astrocyte minimum system

Astrocytes have a regulatory function on the central nervous system (CNS), especially in the temperature-sensitive hippocampal region. In order to explore the thermosensitive dynamic mechanism of astrocytes in the CNS, we establish a neuron-astrocyte minimum system to analyze the synchronization change characteristics based on the Hodgkin-Huxley model, in which a pyramidal cell and an interneuron are connected by an astrocyte. The temperature range is set as 0 ℃-40 ℃ to juggle between theoretical calculation and the reality of a brain environment. It is shown that the synchronization of thermosensitive neurons exhibits nonlinear behavior with changes in astrocyte parameters. At a temperature range of 0 ℃-18 ℃, the effects of the astrocyte can provide a tremendous influence on neurons in synchronization. We find the existence of a value for inositol triphosphate (IP₃) production rate and feedback intensities of astrocytes to neurons, which can ensure the weak synchronization of two neurons. In addition, it is revealed that the regulation of astrocytes to pyramidal cells is more sensitive than that to interneurons. Finally, it is shown that the synchronization and phase transition of neurons depend on the change in Ca²⁺ concentration at the temperature of weak synchronization. The results in this paper provide some enlightenment on the mechanism of cognitive dysfunction and neurological disorders with astrocytes.     

Atomic structure and transition properties of H-like Al in hot and dense plasmas

The atomic structure and transition properties of H-like Al embedded in hot and dense plasmas are investigated using modified GRASP2 K code. The plasma screening effect on the nucleus is described using the self-consistent field ion sphere model. The effective nuclear potential decreases much more quickly with increasing average free electron density,but increases slightly with increasing electron temperature. The variations of the transition energies, transition probabilities,and oscillator strengths with the free electron density and electron temperature are the same as that of the effective nuclear potential. The results reported in this work agree well with other available theoretical results and are useful for plasma diagnostics.     

YL－110型流动注射测金装置的研制

研制了一台流动注射测金装置。该装置由一台四道蠕动泵、两支旋转阀，一支８５３１纤维分离富集柱和有关电路组成一个整体，靠蠕动泵自动输送试样溶液，酸洗液和金洗脱液，使金在Φ３×４０ｍｍ的微型纤维柱上富集，由控制电路控制旋转阀切换自动完成柱平衡，进样，洗涤，洗脱过程，金洗脱液自动送入原子吸收分光光度计测定金。８５３１纤维是金的良好吸附剂，具有选择性容量大的优点。试样经王水分解后可直接进样测定。该装置与原子吸收分光光度计联用测定金。金的特征浓度可达０．６ｎｇ／ｍＬ每小时可测定４０～６０次。用本装置分析０．１６μｇ／ｍＬ金溶液，ＲＳＤ为０．８％。用于分析化探样品，铜精矿，电解铜等试样中金，得到满意的结果。     

基于Matlab的IIR数字滤波器的设计与实现

提出了一种采用Matlab的数字滤波器设计工具箱FDATOOL快速有效设计IIR数字滤波器的方法,可实时调整滤波器的参数从而使滤波器的设计达到最优。概述了FDATOOL的使用方法,采用DSP Builder建立了实现模型,给出了基于FPGA的IIR数字滤波器的实现流程,并且在最后使用Simulink进行仿真,给出了仿真波形。     

宽带城域网中的计费方式

近年来,随着我国各地的城市信息化建设步伐加快,宽带城域网已经成为城市信息化基础建设的重要部分。对于已经建成的宽带城域网,传统的包月计费方式已经不能满足运营商在激烈竞争中吸引更多用户的需求,为此需要提供更加灵活的计费方式和更多的特色业务,从依靠带宽盈利转向依靠服务和业务盈利。     

基于IP Core的高速数据发送卡的设计

讨论使用FPGA来实现PCI IP Core的方法,介绍高速数据发送卡的功能和结构,通过实际工作描述使用IP Core来实现数据发送卡的逻辑控制设计,以及PCI WDM驱动程序的设计.     

基于ARM7的无线传感器网络节点能量管理初探

为了研究无线传感器网络能量管理和组网技术,采用ARM基高性能、低功耗微控制器LPC2138为核心制作了一种新型无线传感器网络节点,该节点由两节AA电池供电.说明了该节点的硬件构成及设计方法,介绍了该无线传感器网络节点使用的电池模型,并给出了一组该节点有效工作状态下的功率.