全球遥测数据处理系统

各种实验和试验计划都有一种倾向,即需要多套重复的处理系统以满足它们各自的需要。在某些情况下,不断购进新的设备;在另一些情况下,又不得不使用不可靠的旧设备。“遥测数据处理系统”(TDRS)计划是一项新的技术进展,它为将来的试验计划提供实时的、集中而可靠的数据处理。现代通信技术使这种处理可为在任一地方进行的试验服务,使原来将数据送到工程师手里的时间减少了几天。本文阐明了采用这种系统的必要性,描述了选择所用设备的基本依据,并报道了进展情况。     

2000年及其以后的GPS

一、引言 GPS是一个军用导航定位系统,象所有无线电导航系统一样,也可供民间各部门使用。该系统刚完成了从研制阶段到实用阶段的过渡。为了预测2000年后GPS将会如何,必须首先确定90年代进入全面工作状态,经成熟之后该系统是什么样?该系统建成投入工作之后,会有一些外界因素要求它作某些改变。下面我们主要从GPS的民用角度来研究一下这些可能的改变。影响GPS改变的外界因素至少来4个方面:GPS的军方要求、钱、技术进展和用户要求。这些外界因素可能引起GPS的民用计划和政策发生变化。这些外界因素和/或新政策、新计划将会影响GPS的硬件和软件。除了系统和政策的改变,若干GPS新的应用将会出现,GPS在各种运载体上的安装和组合也会出现新的方法。     

330分钟双发延程飞行的维护策略

延长ETOPS时间可能意味着维修策略的改变。2011年12月,新西兰航空公司的一架波音777-300ER飞机顺利完成了洛杉矶-奥克兰的直飞,这是该航空公司首次实施240分钟双发延程飞行(ETOPS)。但240分钟并不是ETOPS的极限,目前330分钟正成为     

Near Earth Vortices Driving of Field Aligned Currents Based on Magnetosphere Multiscale and Swarm Observations

A long-standing mystery in the study of Field-Aligned Currents (FACs) has been that:how the currents are generated and why they appear to be much stronger at high altitudes than in the ionosphere.Here we present two events of magnetotail FACs observed by the Magnetospheric Multiscale Spacecraft (MMS) on 1st July and 14th July 2016,to show how the Substorm Current Wedges (SCW) were formed.The results show that particles were transferred heading towards the Earth during the expansion phase of substorms. The azimuthal flow formed clockwise (counter-clockwise) vortex-like motion,and then generated downward (upward) FACs on the tailward/poleward side of the distorted field with opposite vorticity on their Earthward/equatorward side.We also analyzed the Region 1 FACs observed by the Earth Explorer Swarm spacecraft on 1st July 2016 and found that they were associated with FACs observed by MMS,although differing by a factor of 10.This difference suggests that either there was the closure of the currents at altitudes above 500 km or the currents were not strictly parallel to B and closed at longitudes away from where they were generated.      

高级靶场测量飞机

本文描述了高级靶场测量飞机(ARIA)及其目前和未来在全球范围内保障试验和鉴定活动的计划。     

“阿里安”5伏尔甘HM60发动机

人们对“阿里安”5的推进系统提出了一个棘手的最佳化问题.现选择了一种混合系统,它包括:——一台由伏尔甘HM60发动机作为氢氧推进的芯级;——两侧各有一台固体推进器.由于该方法比单一推进具有更大的可靠性,因此在所有芯级研制方案中,这种方法已被人们所接受.     

用于通信技术卫星(CTS)带有隔离式引发系统的高性能远地点发动机的设计、研制和试验

加拿大电信局和美国宇航局(NASA)联合研制的通信技术卫星(以下简称 CTS)将于1975年下半年发射。为这一卫星研制的远地点发动机代表了远地点发动机技术中新的发展方向。钛合金壳体、88%固体含量的端羧基聚丁二烯推进剂和轻质喷管使这一发动机获得高性能指标。由于采用隔离式安全发火装置减轻了重量并简化了总体布局。装有远地点发动机的卫星的大量试验,在研制计划初期就已提供了许多必需的数据,以便及时地提供一个可靠的卫星。     

A new application of LBNP to measure orthostatic tolerance before and after 0-g simulation (water immersion)

Lower body negative pressure (LBNP) remains an important device for the generation of orthostatic stress in the space flight environment as well as a tool to measure inflight and postflight changes in orthostatic response.

These applied levels of LBNP have typically not exceeded 50–60 mm Hg negative pressure. Information is incomplete as to the levels of absolute LBNP orthostatic tolerance, and the factors responsible for their variance. A better definition of the tolerance limits for males and females could be expected to aid the evaluation of lower levels of LBNP.

An LBNP device was built to study absolute orthostatic tolerance; additionally, another LBNP device was constructed to permit orthostatic tolerance testing directly after a controlled water immersion period.

Absolute LBNP orthostatic tolerance patterns are analyzed for a group of males and females (series I). A preliminary statement on the variations of LBNP orthostatic tolerance after limited periods of water immersion and bed rest is also provided (series II).     

Home sweet orbital home

The design of Space Station Freedom is discussed, with an emphasis on the measures taken to ensure the morale and productivity of the inhabitants. Special efforts have been taken to design the station with creature comforts of Earth, such as better food preparation and hygiene equipment than is found in current or past spacecraft. The galley for food storage and preparation is described, as are the shower and laundry facilities. Designers of the space station hope to ensure astronaut mental health and productivity by supplying them with a current working and living space.     

自动液氮加注系统

大量的光谱学的实验和其它物理测量必须在持续一段时间的液氮温度中进行。从最简单的杜瓦瓶到精心制做的自动冷却剂流体