期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
基于步行GPS轨迹的路网提取方法 被引量:15
1
作者 欧阳鸿 刘建勋 +2 位作者 刘毅志 廖祝华 陈佘喜 《计算机与现代化》 2014年第2期124-128,共5页
准确提取和及时更新路网信息,对于道路规划和车辆导航等方面至关重要。目前,基于GPS轨迹的路网提取方法一般是从浮动车或出租车的GPS轨迹中挖掘城市主干路网。然而,现有方法忽略了小路的自动提取,它对于抗震救灾、小区导航或乡村游览等... 准确提取和及时更新路网信息,对于道路规划和车辆导航等方面至关重要。目前,基于GPS轨迹的路网提取方法一般是从浮动车或出租车的GPS轨迹中挖掘城市主干路网。然而,现有方法忽略了小路的自动提取,它对于抗震救灾、小区导航或乡村游览等场合非常重要。因此,本文提出基于步行GPS轨迹的路网提取方法,分为数据预处理、道路中心线生成和路网精度评价3个部分。其中,先后采用轨迹点聚类、聚类点分割和中心线拟合等方法生成道路中心线。通过自行采集的步行GPS数据进行实验,结果表明,本文方法能够准确提取路网,覆盖率可达96.21%,而误检率仅3.26%;并且能够提取小路和更新路网。 展开更多
关键词 路网提取 步行轨迹 小路提取 聚类算法 曲线拟合
下载PDF
Small-Signal Equivalent Circuit Modeling of a Photodetector Chip 被引量:1
2
作者 苗昂 李轶群 +4 位作者 吴强 崔海林 黄永清 黄辉 任晓敏 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1878-1882,共5页
A small-signal equivalent circuit model and the ted. The equivalent lumped circuit, which takes the main extraction techniques for photodetector chips are presen- factors that limit a photodetector's RF performance i... A small-signal equivalent circuit model and the ted. The equivalent lumped circuit, which takes the main extraction techniques for photodetector chips are presen- factors that limit a photodetector's RF performance into consideration,is first determined based on the device's physical structure. The photodetector's S parameters are then on-wafer measured, and the measured raw data are processed with further calibration. A genetic algorithm is used to fit the measured data, thereby allowing us to calculate each parameter value of the model. Experimental resuits show that the modeled parameters are well matched to the measurements in a frequency range from 130MHz to 20GHz, and the proposed method is proved feasible. This model can give an exact description of the photodetector chip's high frequency performance,which enables an effective circuit-level prediction for photodetector and optoelectronic integrated circuits. 展开更多
关键词 small-signal equivalent circuit model of photodetector parameter extraction high frequency meas-urement genetic algorithm
下载PDF
Abstraction of Small Signal Equivalent Circuit Parameters of Enhancement-Mode InGaP/AlGaAs/InGaAs PHEMT
3
作者 徐静波 尹军舰 +3 位作者 张海英 李潇 刘亮 叶甜春 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第3期361-364,共4页
An extraction method of the component parameter values of an enhancement-mode InGaP/AIGaAs/In-GaAs PHEMT small signal equivalent circuit is presented,and these component parameter values are extracted by using the EEH... An extraction method of the component parameter values of an enhancement-mode InGaP/AIGaAs/In-GaAs PHEMT small signal equivalent circuit is presented,and these component parameter values are extracted by using the EEHEMT1 model of IC-CAP software. The extraction results are verified by ADS software,and the DC I-V curves and S parameters simulated by ADS are basically accordant with those of the test results. These results indicate that the EEHEMT1 model can be used for extracting the component parameters of an enhancement-mode PHEMT. 展开更多
关键词 ENHANCEMENT-MODE InGaP/AIGaAs/InGaAs PHEMT small signal equivalent circuit parameter extraction
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部