基于ARM Linux的门禁系统的设计与实现

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。

A {Co-32} Nanosphere Supported by p-tert-Butylthiacalix[4]arene

Calixarene-capped Co-32 clusters are constructed by a sodalite Co-24(II) cage and an encapsulated Co-8(III) cube. The spherical units are arranged into three isomeric structures, two of which are stacked by the bcc lattices and the third of which is assembled by the cubic closest packing of the spherical units.

Synthesis and self-assembly of a novel Y-shaped copolymer with a helical polypeptide arm

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.

Synthesis of Arm-6 polystyrene by atom transfer radical polymerization

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.

Synthesis of eight-arm polystyrene by atom transfer radical polymerization

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.

MISCIBILITY, MICROSTRUCTURE, AND DYNAMICS OF BLENDS CONTAINING BLOCK-COPOLYMER .3. MOLECULAR-MOTION IN HOMOPOLYSTYRENE AND POLYSTYRENE 4-ARM STYRENE-BUTADIENE STAR BLOCK-COPOLYMER BLENDS

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)

SUPERCONDUCTIVITY IN BI1.5PB0.4SBXSR2CA2CU2OY SYSTEM (X=0-0.32)

The effect of doping with various amount of Sb (0.06-0.32) to (Bi,Pb):Sr:Ca:Cu = 1:1:1:1 system were studied with XRD and Tc measurements. The presence of Sb promotes the conversion of low Tc phase (2212 phase) to high Tc phase (2223 phase) and at around Sb = 0.18 the 2212 phase nearly completely disappears; but at the same time a new phase of unknown structure appears even with Sb = 0.06 showing that the incorporation of Sb into the Bi-based superconducting phase is of very low concentration. Tc measurements show that the optimum concentration of Sb-doping is around 0.10 and that unknown phase has an adverse effect to the superconducting properties; a composition disproportion at the surface of pellet was observed.

基于ARM的研磨抛光机器人运动控制器的设计

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。

基于ARM的可编程控制系统实现

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。

基于ARM的智能型定氮仪的研制

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。

ARM处理器在AFM纳米操作系统中的应用

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。