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Helene L. Winters Deborah L. Domingue Teck H. Choo Raymond Espiritu Christopher Hash Erick Malaret Alan A. Mick Joseph P. Skura Joshua Steele 《Space Science Reviews》2007,131(1-4):601-623
The MESSENGER Science Operations Center (SOC) is an integrated set of subsystems and personnel whose purpose is to obtain,
provide, and preserve the scientific measurements and analysis that fulfill the objectives of the MErcury Surface, Space ENvironment,
GEochemistry, and Ranging (MESSENGER) mission. The SOC has two main functional areas. The first is to facilitate science instrument
planning and operational activities, including related spacecraft guidance and control operations, and to work closely with
the Mission Operations Center to implement those plans. The second functional area, data management and analysis, involves
the receipt of science-related telemetry, reformatting and cataloging this telemetry and related ancillary information, retaining
the science data for use by the MESSENGER Science Team, and preparing data archives for delivery to the Planetary Data System;
and the provision of operational assistance to the instrument and science teams in executing their algorithms and generating
higher-level data products. 相似文献
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刘书华 《西安航空技术高等专科学校学报》2007,25(5):72-73,80
通过剖析传统《机械设计基础》考试方法存在的弊端,从考试系统的建立、系统的组成与开发、系统的使用与特点等方面介绍《机械设计基础》网上考试系统的设计思路,并综合分析了网上考试系统试题的生成、在线学习和系统维护等多种功能的实现从而发挥了网络资源在教学和管理中的优势。 相似文献
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T.G. Guzik S. BesseA. Calongne A. DominiqueS.B. Ellison R. GouldD. Granger D. OlanoD. Smith M. StewartJ.P. Wefel 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
The High Altitude Student Platform (HASP) was originally conceived to provide student groups with access to the near-space environment for flight durations and experiment capabilities intermediate between what is possible with small sounding balloons and low Earth orbit rocket launches. HASP is designed to carry up to twelve student payloads to an altitude of about 36 km with flight durations of 15–20 h using a small zero-pressure polyethylene film balloon. This provides a flight capability that can be used to flight-test compact satellites, prototypes and other small payloads designed and built by students. HASP includes a standard mechanical, power and communication interface for the student payload to simplify integration and allows the payloads to be fully exercised. Over the last two years a partnership between the NASA Balloon Program Office (BPO), Columbia Scientific Balloon Facility (CSBF), Louisiana State University (LSU), the Louisiana Board of Regents (BoR), and the Louisiana Space Consortium (LaSPACE) has led to the development, construction and, finally, the first flight of HASP with a complement of eight student payloads on September 4, 2006. Here we discuss the primary as-built HASP systems and features, the student payload interface, HASP performance during the first flight and plans for continuing HASP flights. The HASP project maintains a website at http://laspace.lsu.edu/hasp/ where flight application, interface documentation and status information can be obtained. 相似文献
667.
L. Habash Krause A. Franz A. Stevenson 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
This paper presents an overview of the mathematical foundations for techniques in Exploratory Data Analysis (EDA) for the purpose of investigating the relationships among the numerous variables in large sets of multivariate space weather data. Specifically, we cover techniques in Principal Components Analysis (PCA) and Common Factor Analysis (CFA). These techniques are illustrated using space weather activity indices collected during the year 2002 and the corresponding noon-time hmF2 data from the International Reference Ionosphere (IRI). A CFA is used to categorize the activity indices, and a PCA is used to derive two macro-indices of activity to ascertain the strength of solar and geomagnetic activity. These macro-indices are then used to compare and contrast IRI’s noon-time hmF2 values at six different geographic stations. It was found that the correlation between hmF2 and the macro-indices more accurately represented the variation of this correlation with latitude found in previous studies than if we used an isolated conventional index, such as SSN and AE. We also found that the daily maximum value of the Polar Cap Index was dependent on both solar and geomagnetic activity, but the closely-related cross-Polar Cap Potential was solely associated with elevated levels of geomagnetic activity, which is a unique result compared to previous studies. We argue that the discrepancy can be explained by the difference in experiment designs between the two studies. This paper demonstrates the usefulness of EDA in space weather studies of large multivariate data sets. 相似文献
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为了消除信息交换中随机信号的传输误码,设计一种接收器对输入的随机信号进行检测。当产生传输误码时,统计量的分布密度函数为,其中为未出现传输误码时,统计量的分布密度函数,P(y,p_σ,n)是以y=0为极小值的偶函数。以识别的最小错误概率为检测准则,检测的门限为方程P(y,p_σ,n)=1的根。因此,最小错误概率检测准则为:P(y,p_σ,n)≥1。 相似文献