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提出了基于RFID技术的远程物资管理系统,并对其进行分析与设计。 相似文献
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Immunochromatographic assays are widely used to detect many analytes. CagA is proved to be associated closely with initiation of gastric carcinoma. Here, we reported that a charge-coupled device (CCD)-based test strip reader combined with CdS quantum dot-labeled lateral flow strips for quantitative detection of CagA was developed, which used 365-nm ultraviolet LED as the excitation light source, and captured the test strip images through an acquisition module. Then, the captured image was transferred to the computer and was processed by a software system. A revised weighted threshold histogram equalization (WTHE) image processing algorithm was applied to analyze the result. CdS quantum dot-labeled lateral flow strips for detection of CagA were prepared. One hundred sera samples from clinical patients with gastric cancer and healthy people were prepared for detection, which demonstrated that the device could realize rapid, stable, and point-of-care detection, with a sensitivity of 20 pg/mL. 相似文献
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This paper proposes an efficient adaptive hierarchical artificial immune system (AHAIS) for complex global optimization problems. In the proposed AHAIS optimization, a hierarchy with top-bottom levels is used to construct the antibody population, where some antibodies with higher affinity become the top-level elitist antibodies and the other antibodies with lower affinity become the bottom-level common antibodies. The elitist antibodies experience different evolutionary operators from those common antibodies, and a well-designed dynamic updating strategy is used to guide the evolution and retrogradation of antibodies between two levels. In detail, the elitist antibodies focus on self-learning and local searching while the common antibodies emphasize elitist-learning and global searching. In addition, an adaptive searching step length adjustment mechanism is proposed to capture more accurate solutions. The suppression operator introduces an upper limit of the similarity-based threshold by considering the concentration of the candidate antibodies. To evaluate the effectiveness and the efficiency of algorithms, a series of comparative numerical simulations are arranged among the proposed AHAIS, DE, PSO, opt-aiNet and IA-AIS, where eight benchmark functions are selected as testbeds. The simulation results prove that the proposed AHAIS is an efficient method and outperforms DE, PSO, opt-aiNet and IA-AIS in convergence speed and solution accuracy. Moreover, an industrial application in RFID reader collision avoidance also demonstrates the searching capability and practical value of the proposed AHAIS optimization. 相似文献
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RFID系统主要由阅读器和应答器组成。阅读器包含高频接收模块、控制单元及与应答器连接的耦合元件。高频接收模块以单片集成接收芯片MC3362为核心,结合MC145151构成锁相回路,接收应答器发送的信息。应答器由耦合元件以及高频发射模块组成,其工作所需能量全部由耦合线圈提供,采用自动开关控制应答器与电源的通断以降低功耗。 相似文献
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比色法与HPLC法对比测定桑叶茶中γ-氨基丁酸的含量 总被引:3,自引:0,他引:3
应用酶标仪定量分析桑叶茶(下称桑茶)中的γ-氨基丁酸(γ-aminobutyric acid,GABA),经优化的显色体系在波长640 nm处有最大吸收波长,建立GABA质量浓度与吸光度的相关方程。比色法与高效液相色谱(high performance liquid chromatography,HPLC)法所测GABA在所需质量浓度范围内线性关系均良好(R~20.99)。比色法的平均相对标准偏差为1.28%,平均回收率为98.46%;HPLC法的平均相对标准偏差为0.37%,平均回收率为100.10%。表明2种检测方法均可准确定量测定GABA。经t检验比较分析,无统计学差异。采用比色法对桑叶与桑茶进行检测,结果表明不同加工方式会影响GABA含量。比色法方便快捷,更适合大量样品的检测。 相似文献
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