排序方式： 共有53条查询结果，搜索用时 15 毫秒
41.
μC/OS-Ⅱ及其在ARM微处理器上的移植与应用 总被引：5，自引：0，他引：5
介绍了嵌入式实时操作系统μC／OS-Ⅱ及其移植条件，以优龙公司的一款开发板为硬件平台，阐述了μC／OS-Ⅱ在ARM微处理器（以S3C4480X为例）上的移植过程，并讨论了如何基于μC／OS-Ⅱ进行RTOS体系结构的扩展。 相似文献
42.
Gulf of Mexico sediment sources and sediment transport trends from magnetic susceptibility measurements of surface samples 总被引：1，自引：0，他引：1
The magnetic properties from 200 trigger core-top and Van Veen grab sediment samples recovered from throughout the Gulf of Mexico have been analyzed and used to characterize sediment source and flow pattern distributions. Magnetic parameters included are anhysteretic remanent magnetism (ARM) and magnetic susceptibility (MS) measurements. Results from these measurements are compared to previously determined calcium carbonate percentages, and clay and hematite influx trajectories into the Gulf of Mexico for the same samples reported by Balsam and Beeson [Balsam, W.L. and Beeson, J.P., 2003. Sea-floor sediment distribution in the Gulf of Mexico, Deep-Sea Res. I, 50, 1421–1444.]. The ARM results give an estimate of magnetic grain size distributions, and by analogy, grain size distributions in general, whereas MS patterns show high detrital sediment accumulation zones within the Gulf. The dominant influx of modern high susceptibility sediment into the Gulf of Mexico appears to originate from the Red River, flow into Atchafalaya River Basin and out into the Gulf from Atchafalaya Bay, with significant additional contributions from the Mississippi River through the Southwest Pass of the Mississippi River Delta. This material then moves across the continental shelf and down through the Mississippi Canyon into the deep Gulf where it is redistributed at depths > 3600 m. The eastern shelf margins in the Gulf, offshore from Alabama and Florida, are accumulating calcite- or quartz-rich medium to fine-grained sediment that has a very low or diamagnetic MS signature. From the Louisiana to Texas Gulf coast margins, MS is moderate to high, suggesting a river influx of magnetic constituents from the volcanic fields in New Mexico, and from igneous and metamorphic sources in the Mississippi Basin. Offshore from western Mexico, the MS is high to moderate, but the Yucatan Shelf margin is characterized by low to diamagnetic MS values due to sediment dominated by calcite sands and oozes, a trend that continues to the east onto the West Florida Shelf. Additional measurements of samples collected in association with sites characterized by hydrocarbon seepage exhibit anomalously low MS values. The samples from the lower shelf and slope areas are typified by iron reduction by bacterial organisms in these samples. These results produce anomalous localized lows in the MS trends observed. 相似文献
43.
SWY-����ˮλ�ǵ����� 总被引：1，自引：0，他引：1
?????SWY-?????λ???????????????￡????????????????λ?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????32λARM920T????????????????wince????????????????????????????????????????????????????????????????????????????λ????????????????á?????????????????????????????????????????????????????????????????????????????? 相似文献
44.
ARM技术的快速发展与GPS技术在外业调绘领域中的广泛应用,使地图信息快速采集成为可能。为了进一步提高地图信息外业采集的工作效率和技术水准,设计一种基于ARM核心技术集成电路的地图信息采集终端设备,将多接口、高频率、大容量、具有GPS定位功能的模块电路进行集成,再结合GIS软件编程技术,从硬件设备和软件程序进行研究。 相似文献
45.
基于嵌入式Linux数据采集系统的设计 总被引：1，自引：0，他引：1
介绍了使用ARM芯片LPC2138进行数据采集系统设计的方法,其中包括Linux操作系统下基于ARM芯片LPC2138的UART串口驱动程序的开发,利用串口与GPRS模块相连实现无线上网的方法。由于系统体积小,性能好且价格较为经济,在大规模气象监测网络体系中将发挥积极的作用。 相似文献
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47.
曾珂 《成都信息工程学院学报》2007,22(1):5-8
用基于ARM的AT91M40400及μC／OSⅡ系统设计了数据采集系统，给出了系统原理框图及设计要点。 相似文献
48.
There is agreement that ultrafine maghemite grains (<100 nm) are responsible for the magnetic enhancement of Chinese loess. Recent studies show that grain size distribution of ultrafine pedogenic maghemite grains within the aeolian sequences on the central Chinese Loess Plateau deposited in the last 8 Ma is consistent. However, whether the observed grain size distribution of ultrafine pedogenic maghemite grains can be observed in the western Chinese Loess Plateau and modern soils is not entirely clear. Here we find that young surface soil samples across the Chinese Loess Plateau and early Neogene loessic soils from the western Chinese Loess Plateau also show consistent grain size distribution with that of ultrafine pedogenic maghemite grains on the central Chinese Loess Plateau. The fact that young surface soil samples show apparent magnetic enhancement suggests that the ultrafine pedogenic maghemite grains derive from oxidation of ultrafine magnetite grains. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
49.
针对现有的GPS数据采集设备在数据共享、硬件兼容性和便携性方面存在不足的问题,提出一种新的GPS数据采集设备的设计方案。该设计在硬件上采用ARM微控器和SD卡储存器,软件上结合UC/OS-II嵌入式实时操作系统和FAT32文件系统。对样机的测试表明,满足设计要求,具有数据可共享,低功耗,兼容多种GPS-OEM板,便于携带的特点。 相似文献
50.