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排序方式: 共有2332条查询结果,搜索用时 15 毫秒
1.
Luan Yu Shi Yuhang Wu Wanyin Liu Zhiyao Chang Hai Cheng Jun 《Knowledge and Information Systems》2021,63(10):2791-2814
Knowledge and Information Systems - In the past decade, human activity recognition (HAR) has grown in popularity due to its applications in security and entertainment. As recent years have... 相似文献
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为了让普通用户方便地得到像素画卡通头像,提出一种自动从人脸照片生成像素画的算法.首先通过对脸部特征定位找到关键特征,然后在低分辨率下对特征的形状和位置进行优化调整;在调整后的各个区域采用"画家调色盘"色彩校正方法对其颜色进行校正,生成像素画.实验结果表明,该算法能够生成结构清晰、色彩明快的像素画. 相似文献
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栾新源 《单片机与嵌入式系统应用》2011,11(5):21-24
用FPGA+ARM的方式设计低成本加固液晶显示器控制电路.FPGA负责对比度调整,ARM微控制器负责温度、亮度、通信、键盘扫描的控制.创新之处在于用低成本架构取代老方案,缩短开发周期,并引入LED背光源辅助加热、动态背光源降低功耗的思想. 相似文献
5.
Voting systems are common tools in a variety of areas. This paper studies parameterized computational complexity of control of Plurality, Condorcet and Approval voting systems, respectively. The types of controls considered include adding or deleting candidates or voters, under constructive or destructive setting. We obtain the following results: (1) constructive control by adding candidates in Plurality voting is W[2]-hard with respect to the parameter “number of added candidates”, (2) destructive control by adding candidates in Plurality voting is W[2]-hard with respect to the parameter “number of added candidates”, (3) constructive control by adding voters in Condorcet voting is W[1]-hard with respect to the parameter “number of added voters”, (4) constructive control by deleting voters in Condorcet voting is W[1]-hard with respect to the parameter “number of deleted voters”, (5) constructive control by adding voters in Approval voting is W[1]-hard with respect to the parameter “number of added voters”, and (6) constructive control by deleting voters in Approval voting is W[2]-hard with respect to the parameter “number of deleted voters”. 相似文献
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Yao Yongxun Duan Zhenzhong Li Yuenan Gu Hongwei Hua Zhiqiang Luan Wenzhou Wang Yuan 《中国稀土学报(英文版)》2004,22(Z2)
LiFePO4 cathode material was synthesized by a solid-state reaction using doping several elements (Nb5 ,Zr4 ). The starting materials were mixed with a high-efficient sander and treated thermally under flowing N2. The samples were characterized by X-ray diffraction (XRD), field-emission gun electron microscopy (FEG), and their electrochemical performance was investigated in the term of cycling behavior. Room temperature discharge capacity about 140.6 mA·h·g-1 was obtained at C/5 rate. 相似文献
8.
The asymmetry appearing in the degree of polarization (DOP) distribution of the backscattering polarized light from tissues is investigated by using polarized Monte Carlo simulation. When the incident point is close to the boundary of the lesion inside the tissue, high asymmetry emerges regardless of the polarized direction of the incident light. A noninvasive method based upon the DOP asymmetry of the backscattering light is proposed to locate lesions hidden in live tissues by scanning a point light source. Imaging of the front projection on complicated lesion structures is demonstrated with this method. Its transverse resolution, which is affected by the wavelength of incident light and the size of the scattering particle, can reach the diameter of the lesion scattering particle theoretically while the best longitudinal detection depth can be achieved by choosing a suitable incident wavelength according to the scattering characters of the tissue. 相似文献
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10.
Xue-ren Zhang Tong Yan Tee Jing-en Luan 《电子与封装》2006,6(2):10-15,4
<正>Packaging of MEMS ( micro-electro-mechanical system ) devices poses more challenges than conventional IC packaging, since the performance of the MEMS devices is highly dependent on packaging processes. A Land Grid Array ( LGA ) package is introduced for MEMS technology based linear multi-axis accelerometers. Finite element modeling is conducted to simulate the warpage behavior of the LGA packages. A method to correlate the package warpage to matrix block warpage has been developed. Warpage for both package and sensor substrate are obtained. Warpage predicted by simulation correlates very well with experimental measurements. Based on this validated method, detailed design analysis with different package geometrical variations are carried out to optimize the package design. With the optimized package structure, the packaging effect on accelerometer signal performance is well controlled. 相似文献