101 resultados para arm

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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介绍了基于ARM和DSP的CSR主环磁场电源控制系统的设计和开发。系统以以太网作为连接各个单元的传输介质,以ARM板卡作为以太网中的一个通信节点,由DSP板卡完成实际的电源控制。实验表明控制效果良好,超过了预期的设计目标。

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ARM(S3C4510B)、CPLD(XC95288XL)和微控制器(MSP430F149)为核心进行实时多路数据采集和控制的冷却储存环(CSR)真空控制系统设计。着重分析了控制系统组成、工作原理、功能实现、硬件电路和软件开发。该控制系统具有适应性与灵活性强、响应速度快、精度高、稳定性好、可靠性高、性价比优越、自我连锁保护等优点,现已成功应用于CSR真空控制系统中。

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门禁系统主要负责对出入通道进行管制,是社区楼宇安全监控系统的一部分。传统的门禁系统通常采用密码识别、卡片识别的方式进行验证,由于密码、卡片容易被盗用、丢失,系统安全性不高。在通信方式上传统门禁系统通常采用RS485或者RS232连接,传输距离、速度和连接终端数均受限制。本文提出的人像识别门禁系统解决方案采用ARM-Linux系统平台,依靠社区宽带综合业务网的传输和存储能力,结合密码、RFID和人像识别三种识别方式,利用网络技术和生物识别技术达到识别率高、响应速度快、扩展能力强的要求,并能够与驻地网的其它业务集成,提供业务级的联动服务。此外,该门禁系统还支持用户使用电话开门,由服务器完成对用户来电的识别和防伪验证。本文工作的主要贡献是:参与了ARM-Linux系统的裁剪、移植和声卡驱动的修改;建立了ARM-Linux交叉编译环境;完成了门禁前端软件系统的整体设计和实现;完成了服务器软件电话呼叫响应子系统的设计。

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novel biodegradable Y-shaped copolymer, poly(L-lactide)(2)-b-poly(gamma-benzyl-L-glutamic acid) (PLLA(2)-b-PBLG), was synthesized by the ring-opening polymerization (ROP) of N-carboxyanhydride of gamma-benzyl-L-glutamate (BLG-NCA) with centrally amino-functionalized poly(L-lactide), PLLA(2)-NH2, as a macroinitiator in a convenient way. The Y-shaped copolymer and its precursors were characterized by H-1 NMR, FT-IR, GPC, WAXD and DSC measurements. The self-assembly of the PLLA(2)-b-PBLG copolymer in toluene and benzyl alcohol was examined. It was found that the self-assembly of the copolymer was dependent on solvent and on relative length of the PBLG block. For a copolymer with PLLA blocks of 26 in total degree of polymerization (DP), if the PBLG block was long enough (e.g., DP = 54 or more), the copolymer/toluene solution became a transparent gel at room temperature. In benzyl alcohol Solution, only PLLA(2)-b-PBLG containing ca. 190 BLG residues could form a gel: those with shorter PBLG blocks (e.g., DP = 54) became nano-scale fibrous aggregates and these aggregates were dispersed in benzyl alcohol homogeneously.

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A new initiator for atom transfer radical polymerization (ATRP), (Cl-2 HCCOO)(3) -C-6 H-3, (TrDCAP),has been designed and successfully synthesized. ATRP of styrene was carried out by using TrDCAP as hexafunctional initiator and the CuCl/bpy catalyst at 130 degrees C in 30% THF via core-first strategy. The Arm-6 PS-AAP was synthesized by etherealization of Arm-6 PS and 4-(4'-methoxyphenylazomethine) phenol (AAP). The initiator and the architectures of the Arm-6 PS were confirmed by H-1-NMR, FT-IR, UV-Vis and GPC.

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A new initiator for atom transfer radical polymerization (ATRP), (Cl2HCCOOCH2)(4)C(TDCAP) was designed and successfully synthesized. The initiator was,used to initiate,the polymerization of styrene via ATRP to method yield an eight-arm polystyrene with functional end-group chlorides. The different polymers could be prepared via ATRP of different monomers at 130 degrees C using TDCAP/CuCl/bPy as the initiating system. The initiator and eight-armed polymer were characterized by means of H-1 NMR, FTIR and GPC.

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The proton spin-spin relaxation times (T-2(H)) at different temperatures (from 160 to 390 K) have been determined for polystyrene (PS) and four-arm star styrene-butadiene block copolymer (SB-4A) and its blends with PS of different molecular weights (M(PS)

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本文设计了研磨抛光机器人分布式控制系统中的一种运动控制器,并对运动控制器基于AT91M40800微控制器的硬件结构、基于μC/OS-Ⅱ实时操作系统的软件模块和采用的参数模糊自整定PID机器人关节位置控制策略进行了详细介绍。实验表明该控制器可以大大降低研磨抛光机器人的位置跟踪误差。提高了关节控制的计算及处理能力,易于扩展和维护。

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采用ARM设计小型可编程控制器,提供基于以太网和OPC标准的组态监控接口。用户采用符合IEC61131-3标准的梯形图方式对控制器自由编程,并通过计算机网络对其进行程序调试、下载和数据通信,从而实现了一套经济实用的小型可编程控制系统。

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通过对凯氏定氮法和整个系统控制原理的分析,介绍了一种基于ARM的测定物质中氮元素含量的系统,该系统采用ARM微控制器LPC2214作为整个系统的控制核心,通过步进电机驱动进行标准溶液的滴定和光电检测确定滴定终点,形成闭环系统,实现了准确测定物质中氮元素的含量。文中给出了系统软硬件设计方案,对其实现方法及关键技术进行了研究。实验结果表明:该系统工作稳定,测量数据准确,具有一定的应用价值。

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文章介绍了在原子力显微镜(AFM)纳米操作系统中ARM处理器的应用及开发,在此基础上搭建了具有3D力反馈的纳米操作系统。结合AFM纳米操作系统的实时性问题,进行了ARM开发板的系统软件架构和PSD(四象限光电检测器)信号的PID控制结果的分析,使纳米操作系统在实时性和成像的质量等方面都得到相应改进。

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近年来,随着微纳米科技的迅速发展,机电产品有望向更微观化、高性能化发展,这将促进材料、制造、电子、生物医学、信息等领域新的科学技术出现,在新的科学技术层次上为可持续发展的理论提供物质和技术保障。微纳米科技最终目标是研究和发现微纳尺度物质所具有的新颖的物理、化学和生物学现象与特性。并以此为基础来设计、制作、组装成新的材料、组件或系统,实现与之相应的特定功能,促进新的科学技术发展与变革,这无疑具有十分重要的科学意义和经济价值。而实现这个目标的使能技术便是微纳米尺度下观测、操作和装配的科学方法与相关的技术和装备,因此开展微纳米操作研究具有特别重要的意义。微纳米操作是微纳米制造科学技术的重要内容之一,使用探针模式的机器人化微纳操作方法,实现在微纳米尺度物体的可控操作,对促进我国微纳米科学技术发展具有特别重要的意义。 目前已有的基于探针的纳米技术装置如SPM (Scanning Probe Microscope)是基于探针模式的纳米观测基本装置。在此基础上研究发展的基于探针的纳米操作已成为纳米科技研究的新领域,是目前世界上各国正在大力开发的前沿研究课题。但目前市场上的SPM等纳米观测设备缺乏驱动控制与信息交互功能和开放界面,限制了用户在此基础上开发纳米操作、装配等功能的能力,因而研究具有信息交互能力的、可进行在线操作控制与宏-微-纳观信息交互的纳米操作监控系统,进而发展成具有自动化/机器人化功能的纳米作业系统队纳米科学技术发展、纳米制造的实现无疑具有重要意义。本论文的科研内容是以面向纳米制造的机器人化系统为研究背景,在自主技术的基础上,开展应用ARM嵌入式系统构成纳米作业系统的实时控制器研究。实时多任务的操作控制系统是纳米作业系统的核心技术,可以实时进行基于探针的传感信息采集、状态反馈控制、形貌观测数据生成、作业运动轨迹生成、位置反馈控制等功能的数据处理与实现。本论文重点介绍以SAMSUNG公司的ARM9处理器芯片S3C2410为嵌入式控制器系统的核心,在移植嵌入式Linux作为操作系统的基础上,开发具有实时数据采集与控制指令、通信功能的人机交互界面。基于ARM的实时控制器的研究为探针模式的纳米观测与操作系统开发提供了关键技术,可以提供开放的AFM系统,促进操作型纳米系统的研究与实现,可以保证纳米观测与操作控制的实时性,可以为纳米作业控制方法提供方便的编程、开发功能。本论文主要研究了面向纳米作业的基于ARM嵌入式实时控制器硬件结构及软件系统的研究与开发过程。首先介绍嵌入式系统的基本概念和特点;其次介绍基于SPM模式的纳米操作系统性能与技术特点;第三,根据纳米作业系统的技术功能要求,详细介绍了具有实时多任务管理功能的硬件系统的设计,重点解决核心板和扩展板各部分功能模块的设计;第四,详细介绍了嵌入式Linux操作系统下的应用程序开发模式及开发过程;最后,详细介绍了嵌入式Linux操作系统下的应用程序开发,主要工作是完成SPM纳米操作系统中的ARM开发平台的功能接口模块的调试及Linux系统下多线程技术在本系统中的应用。本次毕业设计已完成ARM开发平台在整个SPM纳米操作系统中要实现的各个功能模块,结合SPM纳米操作系统的实时性问题,进行了ARM开发平台的系统软件架构分析和利用多线程技术的以太网通信实验,在一定程度上提高了纳米操作系统中的实时性和成像质量。

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To investigate the low temperature fatigue crack propagation behavior of offshore structural steel A131 under random ice loading, three ice failure modes that are commonly present in the Bohai Gulf are simulated according to the vibration stress responses induced by real ice loading. The test data are processed by a universal software FCPUSL developed on the basis of the theory of fatigue crack propagation and statistics. The fundamental parameter controlling the fatigue crack propagation induced by random ice loading is determined to be the amplitude root mean square stress intensity factor K-arm. The test results are presented on the crack propagation diagram where the crack growth rate da/dN is described as the function of K-arm. It is evident that the ice failure modes have great influence on the fatigue crack propagation behavior of the steel in ice-induced vibration. However, some of the experimental phenomena and test results are hard to be physically explained at present. The work in this paper is an initial attempt to investigate the cause of collapse of offshore structures due to ice loading.

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We quantitatively study the domain inversion in a RuO2:LiNbO3 crystal wafer by the digital holographic interferometry. The crystal wafer is placed into one arm of a Mach-Zehnder-type interferometer to record a series of holograms. Making use of the angular spectrum backward propagation algorithm, we reconstruct the optical wave field in the crystal plane. The extracted phase difference from the reconstructed optical wave field is a well linear function of the applied external voltage. We deduce that the linear electro-optic coefficient of the detected RuO2:LiNbO3 crystal sample is 9.1x10(-12) m/V. An unexpected phase contrast at the antiparallel domain wall is observed and the influence of the applied external voltage on it is studied in detail. Also the built-in internal field is quantitatively measured as 0.72 kV/mm. (c) 2006 American Institute of Physics.