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991.
Yong ZhangAuthor VitaeXuejun ZhengAuthor Vitae Tong ZhangAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(2):887-892
Bi0.5Na0.5TiO3-Bi0.5K0.5TiO3 (BNT-BKT) powder is synthesized by a metal-organic decomposition method and characterized by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). A humidity sensor, which is consisted of five pairs of Ag-Pd interdigitated electrodes and an Al2O3 ceramic substrate, is fabricated by spin-coating the BNT-BKT powder on the substrate. Good humidity sensing properties such as high response value, short response and recovery times, and small hysteresis are observed in the sensing measurement. The impedance changes more than four orders of magnitude within the whole humidity range from 11% to 95% relative humidity (RH) at 100 Hz. The response time and recovery time are about 20 and 60 s, respectively. The maximum hysteresis is around 4% RH. The results indicate that BNT-BKT powder is of potential applications for fabricating high performance humidity sensors. 相似文献
992.
Huitao FanAuthor VitaeYi ZengAuthor Vitae Xiujuan XuAuthor VitaeNing LvAuthor Vitae Tong ZhangAuthor Vitae 《Sensors and actuators. B, Chemical》2011,153(1):170-175
Hollow ZnSnO3 microspheres were successfully prepared by hydrothermal method at 160 °C for 12 h. The prepared material was characterized by field emission scanning electron microscope (FESEM), transmission electron microscope (TEM) and X-ray diffraction measurements (XRD). The average diameter of the hollow ZnSnO3 microspheres was in the range of 400-600 nm. Compared with solid ZnSnO3 microspheres structure, the hollow ZnSnO3 microspheres showed better response (S) to butane. To 500 ppm butane, the sensor response (S) of the hollow ZnSnO3 microspheres was 5.79 at the optimum operating temperature of 380 °C, and the response and recovery time were 0.3 s and 0.65 s, respectively. The sensitivities of sensors based on this material were linear with the concentration of butane in the range of 100-1000 ppm. 相似文献
993.
We present the results of a novel micro-beam deflection test used to investigate the static and dynamic mechanical behavior
of submicron-thick metal films. The method demonstrated in this study allows researchers to observe the motion of micro and
nano-scale thin films responding to electrostatic loads, by means of laser reflection measurements at frequency rates of up
to 500 Hz. Researchers fabricated a supporting frame and a novel triangular shaped “paddle” beam designed to provide uniform
plane stress distribution while undergoing deflection. A simple geometric calculation, based on cantilever deflection, enabled
the degree of strain to be determined, which in turn provided the Young’s modus for aluminum film of a given thickness. We
also studied the dynamic behavior using the dynamic frequency response of the beam, generated by electrostatic forces under
various loads and vacuum pressure conditions. Our results showed that air damping has a significant influence on the free
damping behavior of specimens, and only a minor influence on damping frequency. We determined the loss angle and frequency
using sweep frequency and free damping methods, which were very consistent with paddle resonant frequencies. The loss angle
obtained from a simple silicon micro-beam was 2.001 × 10−4°using the free damping method and 2.23 × 10−4°using the sweep frequency method. The dynamic response loss mechanism measured in this experiment provides incentive for the
further study of grain boundary motion and dislocation motion in thin films. 相似文献
994.
Myeong-Gyu Song No-Cheol Park Kyoung-Su Park Young-Pil Park 《Microsystem Technologies》2011,17(5-7):1231-1241
This paper presents the improvement of an asymmetric actuator for optical image stabilization in a mobile phone camera. The required specification was defined from typical hand vibrations. The actuator was designed to have an asymmetric shape to reduce its size, but this design caused several problems. These problems were analyzed, and a new electromagnetic component design that solved these problems was proposed. Detailed dimensions of proposed design were obtained through the design of experiments procedure. Simulation results show that the final model exhibited sufficient performance to satisfy the required specification. 相似文献
995.
In this paper, a new weighted approach on Lagrangian support vector machine for imbalanced data classification problem is proposed. The weight parameters are embedded in the Lagrangian SVM formulation. The training method for weighted Lagrangian SVM is presented and its convergence is proven. The weighted Lagrangian SVM classifier is tested and compared with some other SVMs using synthetic and real data to show its effectiveness and feasibility. 相似文献
996.
为加固网络安全、防范木马攻击,结合实例研究了一种木马隐藏技术,实现了基于加载三级跳和线程守护的隐藏技术,增强了木马的隐蔽性与抗毁性,并提出了该技术相应的防范措施和清除方法。实验结果表明,融入该隐藏技术的木马程序完成了预期的隐藏功能并可以穿透最新的瑞星杀毒软件、瑞星防火墙及硬件防火墙,表明了该隐藏技术的可行性与有效性。 相似文献
997.
利用数据仓库的集成管理能力来辅助医保业务分析是当前我国医疗保障基金管理的研究热点。由于数据仓库构建过程中的每一个环节都可能发生变化,因此一个灵活的元数据管理系统是这个过程不可缺少的。基于一个医保基金风险防控平台数据仓库的构建过程,提出一套适应该平台变化需求的元数据管理解决方案,深化对医保数据仓库中数据的理解,从而完善医保基金的管理和改善数据质量。 相似文献
998.
Eui Chul Lee Kang Ryoung Park Mincheol Whang Kyungha Min 《International Journal of Industrial Ergonomics》2009,39(5):798-806
In this paper, we propose a new way of measuring the degree of eyestrain caused by watching LCD (Liquid Crystal Display) and PDP (Plasma Display Panel) devices. In the experiments, we used a head-mounted eye capturing device and an illumination setup that was designed to avoid specular reflections caused by glasses or contact lenses. Using the captured eye images, we analyzed the eye blinking and changes of pupil sizes (pupil accommodation), using a real-time image processing algorithm. Then we analyzed the degree of eyestrain based on the calculated blinking rate and the pupil accommodation speed. The proposed method offers five improvements over previous methods. First, we perform a comparative analysis of LCD and PDP devices based on the degree of eyestrain. Second, to analyze the degree of eyestrain, we use quantitative data such as the blinking rate and the pupil accommodation speed. Third, we measure the accurate eye blinking and changes of pupil sizes by using high-resolution and zoomed eye image sequences. Fourth, since the camera and illuminative system are based on a specular reflective model, the proposed method can be used with subjects that wear glasses or contact lenses. Fifth, the proposed method is performed at real-time speed.Experimental results showed that the degree of eyestrain when watching LCD devices was greater than that when watching PDP devices.
Relevance to industry
In the large display industry, LCD and PDP devices have become more and more prevalent. In the past, LCD devices have been compared to PDP devices in terms of factors such as spatial resolution, brightness, contrast levels, etc. To perform more accurate comparisons based on human factor, we are proposing a new way of comparing LCD to PDP devices based on the degree of eyestrain. 相似文献999.
Multiresolution-based bilinear recurrent neural network 总被引:1,自引:1,他引:0
Dong-Chul Park 《Knowledge and Information Systems》2009,19(2):235-248
A multiresolution-based bilinear recurrent neural network (MBLRNN) is proposed in this paper. The proposed MBLRNN is based
on the BLRNN that has robust abilities in modeling and predicting time series. The learning process is further improved by
using a multiresolution-based learning algorithm for training the BLRNN so as to make it more robust for the prediction of
time series data. The proposed MBLRNN is applied to the problems of network traffic prediction and electric load forecasting.
Experiments and results on both practical problems show that the proposed MBLRNN outperforms both the traditional multilayer
perceptron type neural network (MLPNN) and the BLRNN in the prediction accuracy.
相似文献
Dong-Chul ParkEmail: Email: |
1000.
<正>目前工控机的发展非常迅速,应用领域也越来越广泛。熟悉工控机行业的人都知道,有一家工控机厂商与众不同,它不做标准机,而是深耕于行业,为行业量身订制工控机,这就是新汉电脑股份有限公司 相似文献