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311.
Sabri Mekaoui Steven Dewitte Christian Conscience André Chevalier 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
Current measurements from DIARAD/VIRGO, PMO6V/VIRGO and ACRIM3 radiometers are of the same order of magnitude, but differ from TIM/SORCE by about 4.5 W m−2. This difference is higher than the sum of the claimed individual absolute uncertainties of the instruments. In this context, the SOLAR payload on the International Space Station embarks the SOVIM package. We give the results of the differential absolute radiometer DIARAD/SOVIM and discuss its associated uncertainties. Compared to DIARAD/VIRGO, all possible efforts have been made to improve the absolute accuracy. Substantial progress has been made in the aperture area and electrical power measurements. The measured TSI value from the left channel of DIARAD/SOVIM during three days of June 2008 is 1364.50 ± 1.38 W m−2 (Total) or ±0.49 W m−2 (if we combine the individual contributions in quadrature). The right channel gives 1364.75 W m−2 with the same uncertainties. These values are about 1.2 W m−2 lower than DIARAD/VIRGO and about 4 W m−2 higher than TIM/SORCE. The difference between the left and right channels measurements is as low as 0.25 W m−2 which is within the improved uncertainty limits. 相似文献
312.
E.G. Cordaro E. Olivares D. Galvez D. Salazar-Aravena D. Laroze 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2012
We present the results of three years of continuous operations and the principal characteristics of our new 3He neutron monitors installed in the Chilean Network of Cosmic-Ray Observatories. During the years 2004 and 2005, we began the construction of this International Geophysical Year (IGY)-type 3He neutron monitor, with the intention of replacing the older proportional tubes of the BF3. These new monitors are installed in stations at locations ranging from the near-equatorial zone to the Antarctic zone. As a reference system, we used our own BF3 neutron monitors and previously complemented the collected data with a Monte Carlo simulation for the proton-yield function response of the Putre neutron monitor. Herein, we present for the first time the data obtained from our new high-mountain observatory located in the Altiplanic zone. 相似文献
313.
Francesco Castellini Andrea Simonetto Roberto Martini Michèle Lavagna 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
This paper analyses the possibility of exploiting a small spacecrafts constellation around Mars to ensure a complete and continuous coverage of the planet, for the purpose of supporting future human and robotic operations and taking advantage of optical transmission techniques. The study foresees such a communications mission to be implemented at least after 2020 and a high data-rate requirement is imposed for the return of huge scientific data from massive robotic exploration or to allow video transmissions from a possible human outpost. 相似文献
314.
2010年河北省召开了发展夜经济工作会议,把提高夜消费水平、做强夜经济作为当前扩大内需的一项重要工作来抓.夜经济是城市经济发展到特定阶段的反映,夜经济已成为一个城乡经济框架中的重要组成部分.在城镇建设三年上水平进程中,廊坊市城镇建设已经开始进入系统提升城市功能和品质,塑造城市特色上水平、出品位、生财富阶段.如何让夜经济... 相似文献
315.
空气动力评估是对飞行器进行全过程、全系统试验与鉴定的重要内容.依据层次分析原理,可分层、分类对飞行器的空气动力特性进行综合评估.采用专家调查法,获得专家个体对评估因素、评估因素的权重、以及评估结果等级与档次的意见;采用综合评估方法综合各专家个体的意见,获得对飞行器空气动力特性综合评估的定性结论和定量结果. 相似文献
316.
317.
常香婷 《华北航天工业学院学报》2005,15(4):48-49
随着市场经济的发展,跨地区甚至跨国的集团化公司大量涌现,而集团公司在经营拓展的同时没有强化对资金的管理,造成集团公司在资金管理方面中出现了诸多问题.要解决这些问题,必须强化资金管理,建立以财务资金管理为核心的内部信息管理系统,运用现代信用工具实行资金集中收付,通过全面预算管理、内部审计等手段有效监控使用资金,保证资金的合理有效使用,提高资金管理水平. 相似文献
318.
We discuss the various problems occurring when trying to fix a geoid or geopotential model using sea level observations sampled
during a limited time span from a bounded geographical domain. Such problems are on the one hand aliasing and spectral leakage,
and on the other, the non-conservation of matter over only part of the world ocean.
In the light of these issues we discuss whether it is sensible to include in a definition of the global geoid the radially
symmetric part of either the mean sea level field itself, or its linear or nonlinear time dependence, arriving at a negative
conclusion.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
319.
本文在介绍EDU-766显示组件总体工作原理的基础之上,重点对显示组件内部的A2视频处理电路卡硬件作了较详细地分析。文中将视频处理电路又分为彩色解码、亮度控制和视频输出三个部分,并力图打破只分析方块图的框框,给出更接近实际的论述及原理电路。 相似文献
320.