SB—3热控涂层电导稳定性能评估

SB—3是一种消光性能好,吸收率和发射率高的黑色热控涂层材料,基底材料是有机化合物。为了增加电导能力和克服表面电荷积累的现象,在涂层中又掺有导电添加剂。对这样一种有应用前途的热控涂层进行比较深入细致的观察研究是十分必要的。通过这方面的评估研究可以指出该涂层的充电性能的变化及规律,也有助于涂层改进并实现在型号上可靠应用的最终目的。     

基于卡尔曼滤波的目标机动判别研究

在对目标方位序列进行卡尔曼滤波的基础上,利用滤波残差的分布特性,对其进行假设检验,可以据此判断方位序列是否发生显著变化,由此判断目标是否机动.为了说明这种方法的有效性,文中给出了一个实例.     

CELSS nutrition system utilizing snails

At the 40th IAF Congress in Malaga, a nutrition system for a lunar base CELSS was presented. A lunar base with a total of eight crew members was envisaged. In this paper, four species of plants--rice, soybean, lettuce and strawberry--were introduced to the system. These plants were sufficient to satisfy fundamental nutritional needs of the crew members. The supply of nutrition from plants and the human nutritional requirements could almost be balanced. Our study revealed that the necessary plant cultivation area per crew member would be nearly 40 m3 in the lunar base. The sources of nutrition considered in the study were energy, sugar, fat, amino acids, inorganic salt and vitamins; however, calcium, vitamin B2, vitamin A and sodium were found to be lacking. Therefore, a subsystem to supply these elements is of considerable value. In this paper, we report on a study for breeding snails and utilizing meat as food. Nutrients supplied from snails are shown to compensate for the above mentioned lacking elements. We evaluate the snail breeder and the associated food supply system as a subsystem of closed ecological life support system.     

Leg venous hemodynamics and leg volumes during a 42 day -6 degrees head-down bedrest

Seven healthy subjects were submitted to a 42-day head down bedrest, where leg venous compliance (venous distensibity index VDI) and leg volumes were assessed by mercury strain gauge plethysmography with venous occlusion and optoelectronic plethysmography, respectively. Plethysmographic and volometric measurements were made, before, during (at days 1, 4, 7, 14, 21, 26, 34 and 41), and after bedrest (days 1, 4, 7, 11 and 30 of the recovery period). Results showed a continuous decrease in leg volumes throughout bedrest, when VDI increased until day 26 of bedrest, and then decreased afterwards. The recovery period was characterized by a rapid return of VDI to prebedrest levels while leg volumes progressively normalised. These results showed that leg venous compliance changes are not always dependant upon skeletal muscle changes, and that factors other than size of muscle compartment are able to determine increases in leg venous compliance during long-term bedrest.     

Spatial orientation during locomotion [correction of locomation] following space flight

To investigate changes in spatial orientation ability and walking performance following space flight, 7 astronaut subjects were asked pre- and post-flight to perform a goal directed locomotion paradigm which consisted of walking a triangular path with and without vision. This new paradigm, involving inputs from different sensory systems, allows quantification of several critical parameters, like orientation performance, walking velocities and postural stability, in a natural walking task. The paper presented here mainly focusses on spatial orientation performance quantified by the errors in walking the previously seen path without vision. Errors in length and reaching the corners did not change significantly from pre- to post-flight, while absolute angular errors slightly increased post-flight. The significant decrease in walking velocity and a change in head-trunk coordination while walking around the corners of the path observed post-flight may suggest that during re-adaptation to gravity the mechanisms which are necessary to perform the task have to be re-accomplished.     

Influence of graviceptives cues at different level of visual information processing: the effect of prolonged weightlessness

We evaluated the influence of prolonged weightlessness on the performance of visual tasks in the course of the Russian-French missions ANTARES, Post-ANTARES and ALTAIR aboard the MIR station. Eight cosmonauts were subjects in two experiments executed pre-flight, in-flight and post-flight sessions.

In the first experiment, cosmonauts performed a task of symmetry detection in 2-D polygons. The results indicate that this detection is locked in a head retinal reference frame rather than in an environmentally defined one as meridional orientations of symmetry axis (vertical and horizontal) elicited faster response times than oblique ones. However, in weightlessness the saliency of a retinally vertical axis of symmetry is no longer significantly different from an horizontal axis. In the second experiment, cosmonauts performed a mental rotation task in which they judged whether two 3-D objects presented in different orientations were identical. Performance on this task is basically identical in weightlessness and normal gravity.     

Lower body negative pressure (LBNP) as a countermeasure for long term spaceflight

The article presents the current status of lower body negative pressure (LBNP) as a countermeasure for preventing orthostatic intolerance after space flight or bed rest. Devices discussed include the Chibis vacuum suit, the Anthrorack device, a collapsible device, and an inflatable device. Two bed rest studies examined the effect of LBNP and exercise on orthostatic tolerance; plasma volume; vasopressin, plasma renin activity, and catecholamines; and side effects.     

俄罗斯将继续开发第五代战斗机

如果说俄罗斯已正式进入苏—37和米格1.44战斗机计划,那么它并没有放弃开发第五代战斗机。据俄罗斯航空工业和空军领导人向新闻媒体透露,2001年5月,俄罗斯正式推出了这个名ILAKΦA的第五代战斗机研制项目。为了研究这种新飞机,第一张工业装配草图已经准备就绪。在俄罗斯     

F-22“猛禽”战斗机综述

介绍了F-22“猛禽”战斗机的研制背景、结构、所用材料以及隐身技术，重点对飞机结构和系统进行了详细论述。     

某涡桨发动机起动监控装置的设计

为解决某涡桨发动机在实际使用中易发生起动超温故障的问题,研制了某发动机起动监控装置,文中介绍了某起动监控装置的研制思路、组成和技术特点.