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Alexander Soloviev Mark Donelan Hans Graber Brian Haus Peter Schlüssel 《Journal of Marine Systems》2007,66(1-4):182
The air–sea CO2 exchange is primarily determined by the boundary-layer processes in the near-surface layer of the ocean since it is a water-side limited gas. As a consequence, the interfacial component of the CO2 transfer velocity can be linked to parameters of turbulence in the near-surface layer of the ocean. The development of remote sensing techniques provides a possibility to quantify the dissipation of the turbulent kinetic energy in the near-surface layer of the ocean and the air–sea CO2 transfer velocity on a global scale. In this work, the dissipation rate of the turbulent kinetic energy in the near-surface layer of the ocean and its patchiness has been linked to the air–sea CO2 transfer velocity with a boundary-layer type model. Field observations of upper ocean turbulence, laboratory studies, and the direct CO2 flux measurements are used to validate the model. The model is then forced with the TOPEX POSEIDON wind speed and significant wave height to demonstrate its applicability for estimating the distribution of the near-surface turbulence dissipation rate and gas transfer velocity for an extended (decadal) time period. A future version of this remote sensing algorithm will incorporate directional wind/wave data being available from QUIKSCAT, a now-cast wave model, and satellite heat fluxes. The inclusion of microwave imagery from the Special Sensor Microwave Imager (SSM/I) and the Synthetic Aperture Radar (SAR) will provide additional information on the fractional whitecap coverage and sea surface turbulence patchiness. 相似文献
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基于美军潜艇作战使命任务的发展变化,介绍了不同时期美军潜射无人机的发展类型概况,分析了美军潜射无人机发展趋势及其作战使命任务、作战体系和作战使用样式以及无人机隐蔽发射适配性,并据此给出了对潜射无人机发展的启示。 相似文献
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为满足车载控制器研发的需求,提出了一种基于GPRS网络通讯的远程监控系统。设计了基于GPRS模块SIM900A的硬件电路和软件程序。数据采集模块从传感器和整车CAN网络采集数据,并通过GPRS模块将所需数据发送到监控服务器。试验证明该系统能够实现对实验数据的实时采集和远程监控,系统运行稳定可靠。 相似文献
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Impact of phytoplankton community size on a linked global ocean optical and ecosystem model 总被引:1,自引:0,他引:1
We isolated the effect phytoplankton cell size has on varying remote sensing reflectance spectra (Rrs(λ)) in the presence of optically active constituents by using optical and radiative transfer models linked in an offline diagnostic calculation to a global biogeochemical/ecosystem/circulation model with explicit phytoplankton size classes. Two case studies were carried out, each with several scenarios to isolate the effects of chlorophyll concentration, phytoplankton cell size, and size-varying phytoplankton absorption on Rrs(λ). The goal of the study was to determine the relative contribution of phytoplankton cell size and chlorophyll to overall Rrs(λ) and to understand where a standard band ratio algorithm (OC4) may under/overestimate chlorophyll due to Rrs(λ) being significantly affected by phytoplankton size. Phytoplankton cell size was found to contribute secondarily to Rrs(λ) variability and to amplify or dampen the seasonal cycle in Rrs(λ), driven by chlorophyll. Size and chlorophyll were found to change in phase at low to mid-latitudes, but were anti-correlated or poorly correlated at high latitudes. Phytoplankton size effects increased model calculated Rrs(443) in the subtropical ocean during local spring through early fall months in both hemispheres and decreased Rrs(443) in the Northern Hemisphere high latitude regions during local summer to fall months. This study attempts to tease apart when/where variability about the OC4 relationship may be associated with cell size variability. The OC4 algorithm may underestimate [Chl] when the fraction of microplankton is elevated, which occurs in the model simulations during local spring/summer months at high latitudes in both hemispheres. 相似文献
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Development of an Autonomous Flight Control System for Small Size Unmanned Helicopter Based on Dynamical Model 总被引:1,自引:0,他引:1
WANG Geng Kondak Konstantin Marek Musial SHENG Huan-ye LU Tian-sheng Hommel Günter 《上海交通大学学报(英文版)》2007,12(6):744-752
It is devoted to the development of an autonomous flight control system for small size unmanned helicopter based on dynamical model. At first, the mathematical model of a small size helicopter is described. After that simple but effective MTCV control algorithm was proposed. The whole flight control algorithm is composed of two parts: orientation controller based on the model for rotation dynamics and a robust position controller for a double integrator. The MTCV block is also used to achieve translation velocity control. To demonstrate the performance of the presented algorithm, simulation results and results achieved in real flight experiments were presented. 相似文献
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电务远程教育培训系统由电务段、车间、工区三级远程教育网络构成,利用管理终端将教学内容导入服务器,通过远程教育服务器中的自动更新管理、数据管理等后台服务功能,将信息同步至信号工区终端,为职工提供了自主学习与考试的信息化平台. 相似文献
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主要提出钩计划打印及其监控系统的总体设计思路,并详细描述了系统设计方案,包括对传送的钩计划内容处理、自动打印、监控打印情况等功能的实现方法及过程。 相似文献