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71.
Feng-Renn JuangAuthor VitaeYean-Kuen FangAuthor Vitae Yen-Ting ChiangAuthor VitaeTse-Heng ChouAuthor Vitae Cheng-I. LinAuthor VitaeCheng-Wei LinAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(1):338-342
The Au/SnO2/n-LTPS MOS Schottky diode prepared on a glass substrate for carbon monoxide (CO) sensing applications is studied. The n-LTPS (n-type low temperature polysilicon) is prepared by excimer laser annealing and PH3 plasma treatment of an amorphous Si thin film on glass substrate. The developed Schottky diode exhibits a high relative response ratio of ∼546% to 100 ppm CO ambient under condition of 200 °C and −3 V bias. The response ratio is better than the reported SnO2 based resistive type CO sensors of 100% and 37%, respectively on poly-alumina and glass substrates or comparable to 390% of Pt-AlGaN/GaN Schottky diode CO sensor. Thus, the Au/SnO2/n-LTPS Schottky diode has the potential to develop a low cost high performance CO sensor. 相似文献
72.
Xiangyi FangAuthor Vitae Chunlong LiuAuthor VitaeXiaoli ChengAuthor Vitae Yaoling WangAuthor VitaeYucong YangAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(2):760-764
A new type of array immunosensor was developed by combining surface plasmon resonance (SPR) and spectral imaging techniques. The system consisted of a monochromator as the wavelength scanning light source, a polarizer, Kretschmann-Raaether attenuated total reflection (ATR) configuration including array sensor chip, and a CCD camera. The images of transmitting light from ATR were recorded versus the wavelength. By averaging gray scales of the pixels in the area of every gold spot from the image series, the complete spectral resonance curve of all sensing spots on the array can be extracted in parallel. The performance of the developed system was evaluated by analyzing interactions of the anti-CD33 monoclonal antibody to its target leukemic cells using 11 cases of human bone marrow specimens. The specimens were also analyzed with flow cytometry method (FCM) for comparison. The initial results measured by the immunosensor array were corresponded with that of FCM, indicating that the developed parallel method might be clinically suitable for immunophenotyping of acute leukemias. The new sensor array system showed the merits of high-throughput, high sensitivity, high specificity, label free and operation convenient. Spots numbers of the array could be increased if suitable technology were adopted for manipulating the micro bio-liquids on the sensor array chip. 相似文献
73.
徐伟 《计算机应用与软件》2011,28(8)
关于磁盘阵列在线重构的研究一直以来都是国内外研究热点。提出面向数据重构算法。面向数据重构算法只对正被使用逻辑块上数据进行重构,而不需对整个磁盘进行数据重构。测试结果说明了面向数据重构算法相对于现有重构方法显著改善了磁盘阵列的重构性能。相对于DOR算法(现在最常用且最有效重构算法之一),面向数据重构算法将重构性能提高了1至2.2倍,并且没有降低重构过程中磁盘阵列服务性能。 相似文献
74.
基于TMS320DM642麦克风阵列声源定位系统 总被引:1,自引:0,他引:1
麦克风声源定位是利用麦克风阵列拾取语音信号,并用数字信号处理技术对其进行分析和处理的声源定位技术.在麦克风阵列声源定位中,语音信号端点的拾取是重要的环节.语音端点检测是对接收到的信号利用端点检测算法分析,以确认麦克风阵列中语音信号到达的端点;并利用麦克风阵列中各麦克风接收到的语音信号的端点的先后,计算出麦克风阵列接收的... 相似文献
75.
无线传感器网络监测数据的汇报机制是目前的研究热点.将目前无线传感器的应用分为非事件类、事件类以及混合类三大类,在设计了监测数据表现形式的基础上,着重对事件判别标准、消息的优先级、数据融合方法以及消息的汇报机制进行了分析和论述.汇报机制采用改进的队列作为缓存空间,以保证级别高的消息能够得到及时有效地的传输.实验结果表明:... 相似文献
76.
By means of simulation and computation, a clocked balanced tunnel-diode comparator, in which the clock signal conditioner is also a tunnel diode, is studied. Simulation and computation of the tunnel-diode asymmetry required for obtaining a minimum offset of the zero level of the compensation voltage are carried out. Simulation of the clocked balanced comparator is performed by means of the Tanner T-Spice program. 相似文献
77.
A planar voltammetric sensor array for use in an electronic tongue was fabricated using a combination of microfabrication techniques. The techniques of e-beam evaporation and pulsed laser deposition were applied to prepare a device that contained all of the electrodes integrated on a silicon die (6 mm × 6 mm). The working electrodes were metals gold, platinum, iridium and rhodium. They were characterized by SEM and EDX, and by electrochemical investigation of the packaged dies with cyclic voltammetry in solutions of sulfuric acid and of ferrocene carboxylic acid in aqueous buffer solution. The robustness and reproducibility of the devices were assessed by potential cycling in acid solution. 相似文献
78.
79.
提出了一种基于时间/数字转换器( TDC)的频率差测量方法.该方法使用延迟链和参考时钟结合的TDC直接数字量化频率差.测量系统与非线性标定模块均在现场可编程门阵列( FPGA)中实现.为了对频率差检测精度进行评估,使用振荡器作为仿真输入信号进行了实验.结果显示:所提出的测量方法对ΔF/F的测量噪声可以达到1 ×10-8/ 槡Hz.在实验结果的基础上,对测量噪声的来源进行了分析. 相似文献
80.
In this study, novel designs of single‐band and tri‐band pattern reconfigurable antennas are proposed. The design of single‐band pattern reconfigurable antenna is accomplished by the use of varactor diodes with the parasitic elements placed on both sides of the driven conventional printed dipole antenna. By tuning the capacitance of varactor, the antenna operates in four different configurations of radiation pattern which include bi‐directional end‐fire, broadside, and uni‐directional end‐fire radiation patterns. The tri‐band pattern reconfigurable antenna design is achieved by the use of parasitic elements on both sides of a tri‐band driven dipole antenna. Dual‐band LC resonators are used as loading elements along the arms of printed dipole to get two lower order modes in addition to the reference dipole mode, resulting in a triband operation of the driven element. The electrical lengths of the parasitic elements with respect to the tri‐band driven element are controlled by suitably embedding varactor and PIN diodes with them. The proposed tri‐band antenna operates in ten different configurations of radiation patterns in the three operating bands. Fully functional prototypes of single‐band and tri‐band pattern reconfigurable antennas along with the DC bias networks have been fabricated to validate the results obtained in simulation. 相似文献