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81.
Lei Shan Meghelli M. Joong-Ho Kim Trewhella J.M. Oprysko M.M. 《Advanced Packaging, IEEE Transactions on》2002,25(2):248-254
A 50 Gb/s package for SiGe BiCMOS 4:1 multiplexer and 1:4 demultiplexer targeting SONET OC-768 serial communication systems is introduced in this work. The package was designed to facilitate bit-error-rate tests and constructed with high-speed coaxial connectors, transmission lines on ceramic substrate, ribbon bonds for chip-to-package interconnects, and a metal composite housing. Numerical simulations were conducted to guide the package design, and both small signal measurements and operational tests were performed thereafter to verify the design and modeling concepts. To keep the model structure under the existing computing capability, the simulation was segmented into three sections - coaxial connector to transmission line, transmission line alone, and transmission line to ribbon bond, and then the results were assembled to predict the performance of the entire package. The package was operated up to 50 Gb/s with low degradation to input digital waveforms and free of error. 相似文献
82.
首先介绍了屏蔽效能的定义,然后根据多芯电缆和同轴电缆的区别与联系,提出了适用于测量多芯屏蔽电缆效能的注入线测试方法,并且比较了测试结果和仿真结果,为测试人员合理选择有效的测试方法提供了依据。 相似文献
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84.
Mingzhi Dai Chao Gao Kinleong Yap Yi Shan Zigui Cao Kuangyang Liao Liang Wang Bo Cheng Shaohua Liu 《Electron Devices, IEEE Transactions on》2008,55(5):1255-1258
An improved hot-hole-involved interface-state generation model is proposed for hot-carrier injection (HCI) degradation in high-voltage (HV) nMOSFETs. This model is based on experiments over a wide range of temperatures, voltage conditions, simulation results, and the underlying physical mechanisms. The model provides a thorough picture of an HCI system in HV nMOSFETs, with hot-hole injection related to an additional maximum electric-field region. The hot-hole injection in HCI is assumed to introduce deeper localized hydrogen states in gate-oxide films than that in negative-bias temperature instabilities. This result facilitates the dispersive transport of hydrogen. Therefore, HCI degradation in HV transistors is explained within the framework of disorder-controlled hydrogen kinetics. The power-law model can successfully predict temperature dependences for HCI degradation. 相似文献
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88.
Shan Zhang Lina Wu Wenqiang Shi Junchang Qin Wei Feng Yu Chen Ruifang Zhang 《Advanced functional materials》2023,33(29):2302360
Photodynamic therapy (PDT) as a non-invasive strategy shows high promise in cancer treatment. However, owing to the hypoxic tumor microenvironment and light irradiation-mediated rapid electron–hole pair recombination, the therapeutic efficacy of PDT is dramatically discounted by limited reactive oxygen species (ROS) generation. Herein, a multifunctional theranostic nanoheterojunction is rationally developed, in which 2D niobium carbide (Nb2C) MXene is in situ grown with barium titanate (BTO) to generate a robust photo-pyroelectric catalyst, termed as BTO@Nb2C nanosheets, for enhanced ROS production, originating from the effective electron–hole pair separation induced by the pyroelectric effect. Under the second near-infrared (NIR-II) laser irradiation, Nb2C MXene core-mediated photonic hyperthermia regulates temperature variation around BTO shells facilitating the electron–hole spatial separation, which reacts with the surrounding O2 and H2O molecules to yield toxic ROS, achieving a synergetic effect by means of combinaterial photothermal therapy with pyrocatalytic therapy. Correspondingly, the engineered BTO@Nb2C composite nanosheets feature benign biocompatibility and high antitumor efficiency with the tumor-inhibition rate of 94.9% in vivo, which can be applied as an imaging-guided real-time non-invasive synergetic dual-mode therapeutic nanomedicine for efficient tumor nanotherapy. 相似文献
89.
在对图像增强的现状以及小波图像增强总体概括的基础上,介绍了多尺度几何分析的产生和发展,分析了多尺度几何分析在图像增强中的应用,阐述了几种具有代表性的自适应和非自适应多尺度几何分析图像增强方法,对存在的问题和进一步的研究方向做出总结和展望。 相似文献
90.
In this paper, an efficient algorithm is proposed to design nearly-perfect-reconstruction (NPR) DFT-modulated filter banks. First, the perfect-reconstruction (PR) condition of the oversampled DFT-modulated filter banks in the frequency domain is transformed into a set of quadratic equations with respect to the prototype filter (PF) in the time domain. Second, the design problem is formulated as an unconstrained optimization problem that involves PR condition and stopband energy of the PF. With the gradient vector of the objective function, an efficient iterative algorithm is presented to design the PF, which is updated with linear matrix equations at each iteration. The algorithm is identified as a modified Newton’s method, and its convergence is proved. Numerical examples and comparison with many other existing methods are included to demonstrate the effectiveness of the proposed method. 相似文献