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91.
92.
Yunfei Wang Xunan Mao Yun He 《Journal of Visual Communication and Image Representation》2010,21(8):889-899
Recent video coding standards with hybrid structure adopt variable block-size processing techniques including variable block-size motion estimation and compensation, variable block-size intra prediction, and variable block-size transform. This paper gives analysis on the variable block-size techniques based on software simulations, and variable block-size transform is specially studied. As a result of the analysis, a generalized dual quad-tree based variable block-size coding (DQTC) structure is proposed. This structure also shows good flexibility and expansibility, in which the prediction block-size set and the transform block-size set can be configured according to requirements and the implementation complexity constraints. Simulation results show a considerable performance improvement for the proposed structure with low implementation complexity while the coding block-size sets and parameters are optimized. 相似文献
93.
基于VB的主从机串行通信系统设计 总被引:2,自引:0,他引:2
串行通信是数据采集系统中最常用的通信手段之一。设计并研制了基于VB的LED大屏幕显示串行数据通信系统,具有编程灵活、控制通信对象容易的优点。通过8250的奇偶校验位与单片机的SM2位的配合,实现了PC机与多个单片机的串行数据通信。介绍了基于VB6.0进行串行通信的流程和编程,较好地解决了同时使用通信方式0与方式1时引起的RXD端口的冲突问题。实验证明,该设计简单、实用,提高了系统设计的效率。 相似文献
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95.
非均匀粘弹介质中有限元地震数字模型 总被引:2,自引:0,他引:2
本文讨论了粘弹介质的地震波响应。假定介质为块状,且块中纵,横波速度及密度、品质因数横向分段线性连续变化。在此条件下,给出了粘弹波动方程制作时间剖面的数学模型,导出了相应的有限元方程并给出其计算方法(包括刚度矩阵、阻尼矩阵)。模拟某实际水平叠加剖面的仿真结果,展示了该方法的效果和水平。 相似文献
96.
97.
Locally Welded Silver Nano‐Network Transparent Electrodes with High Operational Stability by a Simple Alcohol‐Based Chemical Approach 下载免费PDF全文
Haifei Lu Di Zhang Jiaqi Cheng Jian Liu Jian Mao Wallace C. H. Choy 《Advanced functional materials》2015,25(27):4211-4218
As an indispensable aspect of emerging flexible optoelectronics, flexible transparent electrodes, especially those comprised of metal nanowires, have attracted great attentions recently. Welding the nanowire junctions is an effective strategy for reducing the sheet resistance and improving the operational stability of flexible nanowire electrode in practical applications. Herein, a simple alcohol‐based solution approach is proposed to weld crossed silver nanowires by chemically growing silver “solder” at the junctions of the nanowires, forming transparent silver nano‐network electrodes with improved electrical conductivity and operational stability. Remarkably, silver nano‐networks can be rapidly formed by this simple approach under ambient condition and room temperature, requiring no assistance from heat, light, electrical current, or mechanical pressure. Furthermore, our results show that the nano‐network electrode formed from large diameter nanowires offers a better operational stability, whose trend is opposite to that of the untreated electrodes. To demonstrate the potential application of the highly stable silver nano‐network from large diameter nanowires, organic solar cells fabricated on the nano‐network electrode incorporated with silicon dioxide nanoparticles achieve comparable performance to the ITO control device. Consequently, strategy demonstrated in this work can contribute to low‐cost and highly stable transparent electrodes in emerging flexible optoelectronics. 相似文献
98.
99.
Hainan Gao Jiale Mao Yudong Cai Shuhong Li Ye Fu Xiaolan Liu Haiyan Liang Tianyi Zhao Mingjie Liu Lei Jiang 《Advanced functional materials》2021,31(4):2007664
In nature, many biological organisms possess a unique osmoregulation feature that enables them to survive in environments of different salinity, which is called euryhaline characteristics (e.g., salmon that can survive in freshwater and seawater). Drawing inspiration from these salinity-tolerant organisms, here a strategy that integrates two polymer chain segments with different salinity tolerances is reported to produce a euryhaline hydrogel with stable water retention, constant swelling properties, superoleophobicity, and low-adhesion to oil in aqueous environments over a wide range of salinity. The formation of internal dynamic complementary crosslinks is a key structural factor of the euryhaline attributes. The euryhaline hydrogel-coated meshes can be successfully utilized in various oil/aqueous phase separation in a wide range of salinity. Furthermore, by creating a double network with dynamic bonds, superior euryhaline hydrogel with unique salinity-enhanced mechanical strength can be obtained. It is anticipated that the euryhaline hydrogel will have broad application prospects in complex and variable ionic environments. 相似文献
100.
采用真空电子束蒸镀的方法制备氧化铟锡(ITO)薄膜,以此作为AlGaInP红光发光二极管(LED)的电流扩展层。研究了该LED结构中,不同的芯粒尺寸对ITO电流扩展的影响。结果表明,在电极尺寸一定的情况下,随着芯粒尺寸的变大,ITO电流扩展层对芯粒发光强度的变化起到显著的效果;在电极直径大小为90μm,芯粒尺寸为190μm×190μm时,电流扩展效果最优,亮度增加18.80%,而当芯粒尺寸增大到220μm×220μm时,亮度增加17.01%,其相对电流扩展效果下降。选取适当芯粒尺寸对ITO的电流扩展至关重要。 相似文献