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831.
介绍了uC/OS-II的工作原理及C8051F040的特性,讨论了将uC/OS-II移植到C8051F040单片机中的过程。泵站监控系统实现A/D转换,串口通讯及CAN通讯等任务。 相似文献
832.
John R. Siddorn J. Icarus Allen Jerry C. Blackford Francis J. Gilbert Jason T. Holt Martin W. Holt Jeff P. Osborne Roger Proctor David K. Mills 《Journal of Marine Systems》2007,65(1-4):417
This paper outlines an approach to complex spatio-temporal marine ecosystem modelling as applied to the North Western European Continental Shelf. The model presented here combines an eddy-permitting (approximately 6 km horizontal resolution) baroclinic model, the Proudman Oceanographic Laboratory Coastal Ocean Modelling System (POLCOMS), with the European Regional Seas Ecosystem Model (ERSEM). This has been run within an operational framework using operationally available high resolution atmospheric and lateral boundary forcing, allowing hindcast and near-real time nowcast simulations to be performed. The modelled surface temperature and chlorophyll distributions are presented, and interannual variations discussed. Validation of both the physical and ecosystem submodels show the system to be effective, whilst highlighting areas where improvements in the system can be made. Distinct regional differences in predictive skill are shown. The system presented is ready for operational implementation to provide products and services for use both scientifically and in coastal zone and shelf seas management activities. A programme of work to update the system is already in place. 相似文献
833.
The motions of an infinitely long, two-dimensional runway subjected to the dynamic moving load imposed by an airplane taking
off are investigated. The runway is assumed to be floating in an inviscid fluid and is initially at equilibrium before the
plane takes off. The deformation of the runway resulting from the take-off is wave-like and moves in the same direction as
the plane. The maximum drag occurs when the plane catches up with the first wave. Three different runway configurations were
considered: a baseline and ones which were ten and one hundred times more flexible than the baseline. For these runways, the
added drag to the aircraft was very small, ranging from 1% for the stiffest to 10% for the most flexible runway. 相似文献
834.
835.
Floriano C. M. Pires Luis F. Assis Cassiano M. Souza 《Maritime Policy and Management》2005,32(3):209-226
The Brazilian ship financing system has some unique features. The funds made available to finance the construction and acquisition of ships are sourced from a tax on import and cabotage freight, payable by the shippers. For Brazilian flagged ships, a portion of the tax generated can be used for the payment of loan instalments. This paper analyses the impact of the tax on the economy as a whole, and discusses the distribution of the tax burden between the shipowner and the shipper, taking into account the maritime transport demand elasticities in Brazil. The paper also analyses the effectiveness of the financing system in reducing the capital cost to shipowner, and the distortion effects produced by the utilization of the tax in loan repayments. The conclusion is that there are important distortions that may threaten the recovery of the maritime industry in Brazil. 相似文献
836.
以可用度为中心的舰艇单部件系统备件配置的Monte-Carlo仿真方法 总被引:5,自引:0,他引:5
本文运用Monte-Carlo仿真方法,对以可用度为中心的舰艇备件配置进行了建模仿真,并在计算机上对单部件系统在不同装备可用度要求下的备件配置情况进行了计算,计算结果与解析方法所得结果吻合良好,证明了本文所述方法的正确性和有效性. 相似文献
837.
838.
城市浅埋硬岩超大断面隧道施工技术探讨 总被引:1,自引:0,他引:1
随着城市建设进程的加快,对地面交通、环境影响小的地下空间越来越多地受到青睐,尤其能满足不同功能的大跨地下空间结构更受欢迎。本文以获得2005年詹天佑科技大奖的重庆轻轨二号线临江门车站隧道的施工为例,介绍了城市环境下浅埋硬岩超大断面(大于400 m2)隧道的开挖技术、减震爆破技术、全断面整体式衬砌方法、全面监控量测技术,供同类工程参考。 相似文献
839.
Several issues concerning the implementation and operation of high-speed rail service in the Detroit-Chicago corridor are identified and discussed in this paper. The primary concern is whether such a service is likely to be attractive enough to induce the private sector to provide it. While the outlook for private operation appears pessimistic, consideration of a broader range of potential benefits (e.g., direct and indirect employment) may justify public involvement and investment. 相似文献
840.
随着摩托车出口量的不断增加,我国摩托车出口已从亚洲、非洲市场向欧洲市场扩大。欧洲国家对摩托车整车及配件在安全、排放方面要求较严,特别是中小排量摩托车,几乎普遍要求加装安全限速 相似文献