Buckling of magneto-electro-hygro-thermal piezoelectric nanoplates system embedded in a visco-Pasternak medium based on nonlocal theory

Microsystem Technologies - In this present work the critical loading of magneto-electro-viscoelastic-hygro-thermal (MEVHT) piezoelectric nanoplates embedded in a viscoelastic foundation are...     

Buckling of double functionally-graded nanobeam system under axial load based on nonlocal theory: an analytical approach

Buckling treatment of a bonded compressed double-FG nanobeam system (DFGNBS) is studied in this paper based on Eringen’s nonlocal elasticity theory and Euler–Bernoulli beam model. Differential equations and boundary conditions are obtained using Hamilton’s principle, and the nonlocal theory is employed to derive differential equations in small scale. The material properties are assumed to be functionally graded (FG) along the thickness direction. The synchronous, asynchronous and stationary-type buckling are considered in detail. Results reveal that the small-scale effects are higher with increasing values of nonlocal parameter for the case of in-phase (synchronous) buckling modes in compare to the out-of phase (asynchronous) buckling modes. Increasing the stiffness of the coupling elastic medium double-FG nanobeam system decreases the small-scale effects during the out-of-phase (asynchronous) buckling modes. A detailed parametric study is conducted to investigate the influences of nonlocal parameter, higher modes, spring constant and distributed coefficient of DFGNBS. Some illustrative examples are also stated to verify the present formulation and solutions which showed an excellent agreement.

     

Nonlinear resonant behaviors of embedded thick FG double layered nanoplates via nonlocal strain gradient theory

Microsystem Technologies - This research deals with the nonlinear forced vibration behavior of embedded functionally graded double layered nanoplates with all edges simply supported via nonlocal...     

基于预测原理的嵌入式内存分配算法设计

针对嵌入式系统中内存管理存在的实时性与碎片率较大等问题,分别从时间和空间角度对其进行分析,采用基于预测分配和合并分配原理的预测合并分配机制.从时间上,利用预测线程预测下一次申请内存的大小,提前分配以减少系统等待内存创建的时间;将2次申请的内存块合并成一大块,以大块为申请单位申请内存块,以降低内存块被多次分割导致的内部碎片.μC/OS-Ⅱ平台对比实验结果表明,改进后的预测合并内存分配算法能有效从时间和内存碎片率方面提高系统的整体性能.     

Nanoscale mass nanosensor based on the vibration analysis of embedded magneto-electro-elastic nanoplate made of FGMs via nonlocal Mindlin plate theory

Microsystem Technologies - In the current paper, the sensitivity performance of functionally graded magneto-electro-elastic (FG-MEE) nanoplate with attached nanoparticles as a nanosensor is...     

An embedded system for real-time facial expression recognition based on the extension theory

This paper presents a novel facial expression recognition scheme based on extension theory. The facial region is detected and segmented by using feature invariant approaches. Accurate positions of the lips are then extracted as the features of a face. Next, based on the extension theory, basic facial expressions are classified by evaluating the correlation functions among various lip types and positions of the corners of the mouth. Additionally, the proposed algorithm is implemented using the XScale PXA270 embedded system in order to achieve real-time recognition for various facial expressions. Experimental results demonstrate that the proposed scheme can recognize facial expressions precisely and efficiently.     

基于嵌入式系统的GPRS的设计

嵌入式系统是一个具有特定功能或用途的计算机软硬件结合体,而GPRS是基于现在运行的GSM基础上发展的数据业务。将二者结合起来,设计了一种GPRS系统,它包括硬件和软件两部分;硬件部分以嵌入式处理器S3C2410为核心,分别与GPRS模块、LCD显示和指示灯及键盘人机接口连接;软件部分主要有主程序、功能程序和键盘控制程序。实验结果表明：通过输入不同的AT命令,可开关机、拨打和接听电话、发送和接收短消息、收发E-mail,进行因特网浏览等,功能正确。     

可移植的嵌入式WEB服务器软件设计

本文结合嵌入式系统的具体特点．着重探讨了软件在不同系统之间的可移植性问题,并在此基础上提供了一种可移植嵌入式WEB服务器软件的设计方法。     

基于嵌入式Linux系统的掌上Emap的设计

本文对基于嵌入式Linux系统下不同的图形用户界面(GUI)进行了综合的介绍和比较,并根据Emap的工作原理,提出了在嵌入式Linux系统下的掌上PDA上运行Emap的一种实现模型,具有较强的实用价值。     

基于嵌入式技术的倾角传感器检测系统设计

介绍了加速度传感器MMA7260的工作原理、结构及功能,设计了一个基于ARM的实时嵌人式自动检测系统,使用μC/OS-Ⅱ操作系统,构造一个具有角度测量、相关数据处理以及与上位机通信等功能的现场角度测量单元,上位机则主要完成系统监控和人机交互等功能.     

基于嵌入式系统的RFID中间件设计

针对嵌入式系统的特点,研究了轻量级的嵌入式RFID中间件ERM的体系结构。在ERM体系结构指导下,实现了运行于嵌入式平台的RFID中间件。该中间件体积小、功耗低、占用资源少、性能高,能够满足食品溯源系统的应用需求。     

基于嵌入式GSM-R的监测系统研究

目前绝大多数GSM-R数据监测装置是以PC机为控制器,通过移动监测车辆搭载复杂的设备对铁路沿线的GSM-R信号进行监测。针对此状提出了一种以OMAP-L138作为嵌入式微处理器的GSM-R便携式数据监测系统。本系统利用GSM-R网络,通过监测终端的数据采集模块接收GSM-R数字中频信号,数据处理模块完成GSM-R数字中频信号的监测和干扰分析。若存在干扰,数据解析模块则解析出受干扰小区ID和干扰源小区ID,使分析干扰更具有针对性。该系统体积小,功能丰富,操作控制方便,具有广阔的前景。     

基于嵌入式Web的网络监控系统

针对加油站分布广、通信协议不统一难于实现集成监控,提出了一种基于嵌入式Web的集成监控系统。基于Intel Xscale IXP-422 RISC CPU的嵌入式Web服务器,通过工业以太网互联现场各加油站服务器,完成对现场设备的集成监控。Web浏览控制采用Apache+Html+PHP的方案实现。测试结果表明,该系统安全级别高、实时性好、抗干扰能力强、环境适应性好。     

基于ARMLinux的嵌入式音频系统设计

介绍了由处理器S3C2410和语音处理芯片UDA1380组成的基于ARMlinux的音频系统的构建.提出了软硬件设计方案,并就音频文件的录制、传输、播放进行了探讨.利用IIs总线,IIC总线实现了音频数据及控制信号的传输,在驱动程序设计中通过使用DMA传输及缓存分段技术提高了对音频数据的实时处理,达到了较好实时性效果,实现了录放同步的音频系统.     

Towards a computation system based on set theory

An axiomatic theory of sets and rules is formulated, which permits the use of sets as data structures and allows rules to operate on rules, numbers, or sets. We might call it a “polymorphic set theory”. Our theory combines the λ-calculus with traditional set theories. A natural set-theoretic model of the theory is constructed, establishing the consistency of the theory and bounding its proof-theoretic strength, and giving in a sense its denotational semantics. Another model, a natural recursion-theoretic model, is constructed, in which only recursive operations from integers to integers are represented, even though the logic can be classical. Some related philosophical considerations on the notions of set, type, and data structure are given in an appendix.     

基于嵌入式系统的电力设备紫外监测系统设计

设计主要目的旨在解决电力设备的人为检测的麻烦、不安全,为此引入基于嵌入式计算机系统开发与紫外内窥检测技术相结合的智能检测应用。设计了一套基于嵌入式系统的电力设备紫外监测系统,该系统核心部分主要由紫外探头、嵌入式计算机系统和GPRS模块构成。利用日盲型的紫外传感器检测特定波长的紫外线来正确检测电力设备的放电,并将紫外放电检测和视频内窥技术相结和实现了基于无线GPRS的电力设备紫外放电的远程实时在线监测,最终监控数据通过嵌入式计算机系统处理利用GPRS模块通信网络将信息反馈给工作人员做处理。     

Random vibrations of functionally graded nanobeams based on unified nonlocal strain gradient theory

Microsystem Technologies - In present study the dynamic response of a functionally graded nanobeam supported by visco-elastic foundation to a stationary random excitation, based on non-local strain...     

基于嵌入式计算机网络灯光控制系统

51单片机采集现场调光信息,PCI04嵌入式计算机通过网络传榆调光命令,控制现场灯具发光.回传灯具的发光状态信息,在本机LCD并且通过网络传输到监控主机显示和报警.介绍网络灯光控制系统组成、工作原理和实现方法.重点说明系统调光命令的发布过程和实时性;给出51单片机与PCI04并行软握手的信号、相互配合方法和数据传输过程;深入分析DOs应用程序与Windows应用程序通过网络进行数据交换的方法.     

嵌入式操作系统SolCS中优先级反转问题研究

研发一个嵌入式实时操作系统时需要解决很多任务与共享资源之间的关系问题.介绍了优先级反转问题的理论模型,详细分析和比较了解决优先级反转问题的常规方案--优先级继承协议和优先级天花板协议.重点针对一个自主研发的嵌入式实时操作系统SolCS,提出了一种新的优先级反转问题解决方案并应用于其中,获得一个强实时能力的嵌入式操作系统.     

基于嵌入式系统的便携式多参数监护仪的研究

研究了基于嵌入式计算机的多参数监护仪的设计原理与实现,该系统由多参数信号采集模块、嵌入式计算机系统和GPRS模块构成。介绍了嵌入式计算机系统的硬件和软件组成部分以及应用程序的交叉编译过程,并在此基础上实现了基于Qtopia的应用监护程序。该监护仪以嵌入式计算机为载体,以多参数信号采集模块采集到的血氧、心电、呼吸、血压、体温等人体生物医电方面的信号为基础,实现了基于无线GPRS的多参数实时在线监护。