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排序方式: 共有124条查询结果,搜索用时 4 毫秒
121.
A noncoherent delay-lock loop (DLL) is proposed for code tracking in chip-interleaving (CI) direct sequence (DS) spread spectrum (SS) systems. Analyses show that the proposed loop achieves the same code-tracking performance as the traditional noncoherent DLL does for conventional DS SS systems 相似文献
122.
Nowadays, the broad availability of cameras and embedded systems makes the application of computer vision very promising as a supporting technology for intelligent transportation systems, particularly in the field of vehicle tracking. Although there are several existing trackers, the limitation of using low‐cost cameras, besides the relatively low processing power in embedded systems, makes most of these trackers useless. For the tracker to work under those conditions, the video frame rate must be reduced to decrease the burden on computation. However, doing this will make the vehicle seem to move faster on the observer's side. This phenomenon is called the fast motion challenge. This paper proposes a tracker called dynamic swarm particle (DSP), which solves the challenge. The term particle refers to the particle filter, while the term swarm refers to particle swarm optimization (PSO). The fundamental concept of our method is to exploit the continuity of vehicle dynamic motions by creating dynamic models based on PSO. Based on the experiments, DSP achieves a precision of 0.896 and success rate of 0.755. These results are better than those obtained by several other benchmark trackers. 相似文献
123.
A curvature-corrected low-voltage bandgap reference 总被引:3,自引:0,他引:3
Gunawan M. Meijer G.C.M. Fonderie J. Huijsing J.H. 《Solid-State Circuits, IEEE Journal of》1993,28(6):667-670
A curvature-corrected bandgap reference that can function at supply voltages as low as 1 V, at a supply current of only 100 μA, is presented. After trimming, this bandgap reference has a temperature coefficient (TC) of ±4 p.p.m./°C. The reference voltage is about 200 mV and it can easily be adjusted to higher values. The temperature range of this circuit is from 0 to 125°C. This bandgap reference is realized using a standard bipolar process with base-diffused resistors 相似文献
124.
Nanodiamond‐Palladium Core–Shell Organohybrid Synthesis: A Mild Vapor‐Phase Procedure Enabling Nanolayering Metal onto Functionalized sp3‐Carbon 下载免费PDF全文
Maria A. Gunawan Oana Moncea Didier Poinsot Mariem Keskes Bruno Domenichini Olivier Heintz Rémi Chassagnon Frédéric Herbst Robert M. K. Carlson Jeremy E. P. Dahl Andrey A. Fokin Peter R. Schreiner Jean‐Cyrille Hierso 《Advanced functional materials》2018,28(13)
A novel approach for the bottom‐up construction of hybrid organic–inorganic nanocomposites with an intimate arrangement between sp3‐carbon 3D molecular‐size nanodiamonds (diamondoids) and a coated palladium surface as nanolayer is reported. The construction process is conducted stepwisely from the gas phase, using first controlled vapor‐phase self‐assembly of tailor‐made functionalized diamantane derivatives, followed by low‐temperature (45 °C) chemical vapor deposition of an organometallic complex in a reducing H2 atmosphere over the self‐assembled diamondoid scaffold. The use of self‐assemblies of primary diamantane phosphine and phosphine oxide, which are produced with high structural uniformity and reproducibility, yields new hybrid diamondoid‐palladium materials incorporating Pd? O? PH? diamantane bonding motifs. Additional investigations provide evidence for a very challenging issue in the intimate construction of sp3‐C/metal scaffolds. Scanning electron microscopy and transmission electron microscopy microscopies combined with X‐ray photoelectron spectroscopy surface analysis and EDX bulk analysis confirm the formation of diamondoid‐palladium organohybrids with unique surface layering. The vapor phase‐controlled mild synthetic process allows excellent control over nanocomposite formation and morphology from molecular‐level modifications. As such, this bottom‐up composite building process bridges scales from the molecular (functionalized diamondoids) over nanoscopic (self‐assemblies) to microscopic regime (hybrids), in the challenging association of transition metals with an electronically saturated sp3‐carbon organic host material. 相似文献