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161.
Hyun Woo Nho Jong Yun Kim Jian Wang Hyun‐Joon Shin Sung‐Yool Choi Tae Hyun Yoon 《Journal of synchrotron radiation》2014,21(1):170-176
Here, an in situ probe for scanning transmission X‐ray microscopy (STXM) has been developed and applied to the study of the bipolar resistive switching (BRS) mechanism in an Al/graphene oxide (GO)/Al resistive random access memory (RRAM) device. To perform in situ STXM studies at the C K‐ and O K‐edges, both the RRAM junctions and the I0 junction were fabricated on a single Si3N4 membrane to obtain local XANES spectra at these absorption edges with more delicate I0 normalization. Using this probe combined with the synchrotron‐based STXM technique, it was possible to observe unique chemical changes involved in the BRS process of the Al/GO/Al RRAM device. Reversible oxidation and reduction of GO induced by the externally applied bias voltages were observed at the O K‐edge XANES feature located at 538.2 eV, which strongly supported the oxygen ion drift model that was recently proposed from ex situ transmission electron microscope studies. 相似文献
162.
模块级联是用于绝缘实验所需的高性能对称双极型矩形波脉冲电源的一种方法,为实现级联,需要有能够协调工作的高隔离度直流电源。设计出嵌入到各电源的板级嵌入式控制器BEC,使各BEC作为从节点利用RS485接口和ModBus协议与嵌入式主控制器EHC构成一个主从式现场总线网络,并在主节点EHC的控制下协调工作。利用BEC内的STM32F103C8处理器产生隔离DC-DC桥的互补PWM控制信号和高隔离输出电压,并进行电流和输出电压的隔离检测。由基于电流切换的变参数增量式数字PI算法来确定脉冲宽度值,产生Buck调压电路的闭环PWM控制信号,实现输出电压的调压和稳压控制。实验结果表明该嵌入式控制器能够满足级联式对称双极型矩形波脉冲电源对高隔离度可调直流电源的需要。 相似文献
163.
LIU Chunling WANG Yuxiao SHAN Honglin WANG Jun ZHA Zizhong WANG Qi 《Chinese Journal of Lasers》1999,8(1):92-96
1IntroductionInrecentyears,thepotentialofreversesaturableabsorption(RSA)materialsinopticallimitingandopticalswitchinghavegrad... 相似文献
164.
Yutaka Kuroiwa Naoki Sugimoto Yuki Kondo Tsuneo Manabe Setsuro Ito Arao Nakamura 《Optics Communications》1999,170(4-6):285-289
Quenching treatments were performed on CuCl microcrystallite-doped glasses prepared by a melting method. Radiative decay time measurement and χ(3) measurement for the quenched glasses were performed using ps and ns laser. The glasses showed that the radiative decay time were shortened by one order of magnitude without a decrease of third-order nonlinear susceptibility χ(3) after the quenching treatment from above 300°C. The distorted structure of CuCl microcrystallites quenched from high temperature was considered to be most effective for the shortening of the lifetime of Z3 exciton. 相似文献
165.
The resistance switching behavior has recently attracted great attentions for its application as resistive random access memories (RRAMs) due to a variety of advantages such as simple structure, high-density, high-speed and low-power. As a leading storage media, the transition metal perovskite oxide owns the strong correlation of electrons and the stable crystal structure, which brings out multifunctionality such as ferroelectric, multiferroic, superconductor, and colossal magnetoresistance/electroresistance effect, etc. The existence of rich electronic phases, metal–insulator transition and the nonstoichiometric oxygen in perovskite oxide provides good platforms to insight into the resistive switching mechanisms. 相似文献
166.
Xiaoqing Wen Kohei Miyase Tatsuya Suzuki Seiji Kajihara Laung-Terng Wang Kewal K. Saluja Kozo Kinoshita 《Journal of Electronic Testing》2008,24(4):379-391
At-speed scan testing, based on ATPG and ATE, is indispensable to guarantee timing-related test quality in the DSM era. However,
at-speed scan testing may incur yield loss due to excessive IR-drop caused by high test (shift & capture) switching activity.
This paper discusses the mechanism of circuit malfunction due to IR-drop, and summarizes general approaches to reducing switching
activity, by which highlights the problem of current solutions, i.e. only reducing switching activity for one capture while
the widely used at-speed scan testing based on the launch-off-capture scheme uses two captures. This paper then proposes a
novel X-filling method, called double-capture (DC) X-filling, for generating test vectors with low and balanced capture switching activity for two captures. Applicable to dynamic & static
compaction in any ATPG system, DC X-filling can reduce IR-drop, and thus yield loss, without any circuit/clock modification, timing/circuit overhead, fault coverage
loss, and additional design effort.
相似文献
Xiaoqing WenEmail: |
167.
168.
169.
Moon-Sik Lee 《ETRI Journal》2009,31(3):321-323
A wideband beamforming algorithm for estimating the azimuth angle, elevation angle, velocity, and range using a planar phased radar array with antenna switching is proposed. It uses the time-variant steering vector model. Simulation results illustrating the performance of the proposed beamformer are presented. 相似文献
170.