EVA-related activities in Japan

Recognizing the importance and fertility of the extra vehicular activity technologies in future space development and utilization, some related research activities have been conducted in Japan, though it has not committed itself to developing its own manned space flight capability. The purpose of this paper is to introduce and evaluate these EVA-related activities and to indicate the next step for Japan to get into the era of manned space activities including EVA in reality.     

复合谐振器的寄生谐振及模型

已经研究出几种可用于说明复合谐振器特性的三维模型。由这些模型推算出的谐振频谱(包括寄生谐振频率)与实验数据符合得很好。发现谐振器的几何形状和尺寸是引起寄生谐振的直接原因,并且与主谐振有重要的关系。已经发现谐振频率和材料性能密切相关,并对其实质进行了讨论。     

软土地基处理技术的专利动态及知识产权保护

近几年来，同软土地基处理技术有关的专利申请约１５件。这些专利技术是在先有技术基础上的改进、发展、综合利用和创新。本文简要介绍以工业废料代替砂作为填料、采用新型装置和专用设备、用爆炸法排淤填石和排水以及箍土法处理软土地基等四类方法。同时分别从发明人和非发明人的角度阐述了知识产权保护方面的问题。     

用于航天器的GPS姿态和轨道确定技术

ＧＰＳ接收机的进展已可用于空间导航和姿态确定。正在研制的ＧＰＳＴｅｎｓｏｒ＾ＴＭ将作为空间固态ＧＰＳ姿态和轨道确定接收机，并将进行质量合格检验。     

EUVE卫星的GPS测轨

１９９２年夏，随着极紫外探测卫星一起发射了一台单频ＧＰＳ接收机。ＥＵＶＥ卫星轨道低，并在星体上直接安装了二个天线，可用来研究误差源，以及未来卫星可达到的定轨精度。利用ＧＩＰＳＹ－ＯＡＳＩＳⅡ软件处理了几段ＧＰＳ数据。     

Quantified EEG in different G situations

The electrical activity of the brain (EEG) has been recorded during parabolic flights in trained astronauts and non trained volunteers as well. The Fast Fourier analysis of the EEG activity evidenced more asymmetry between the two brain hemispheres in the subjects who suffered from motion sickness than in the others. However, such a FFT classification does not lead to a discrimination between deterministic and stochastic events. Therefore, a first attempt was made to calculate the dimensionality of "chaotic attractors" in the EEG patterns as a function of the different g-epochs of one parabola. Very preliminary results are given here.     

Drilling systems for extraterrestrial subsurface exploration

Drilling consists of 2 processes: breaking the formation with a bit and removing the drilled cuttings. In rotary drilling, rotational speed and weight on bit are used to control drilling, and the optimization of these parameters can markedly improve drilling performance. Although fluids are used for cuttings removal in terrestrial drilling, most planetary drilling systems conduct dry drilling with an auger. Chip removal via water-ice sublimation (when excavating water-ice-bound formations at pressure below the triple point of water) and pneumatic systems are also possible. Pneumatic systems use the gas or vaporization products of a high-density liquid brought from Earth, gas provided by an in situ compressor, or combustion products of a monopropellant. Drill bits can be divided into coring bits, which excavate an annular shaped hole, and full-faced bits. While cylindrical cores are generally superior as scientific samples, and coring drills have better performance characteristics, full-faced bits are simpler systems because the handling of a core requires a very complex robotic mechanism. The greatest constraints to extraterrestrial drilling are (1) the extreme environmental conditions, such as temperature, dust, and pressure; (2) the light-time communications delay, which necessitates highly autonomous systems; and (3) the mission and science constraints, such as mass and power budgets and the types of drilled samples needed for scientific analysis. A classification scheme based on drilling depth is proposed. Each of the 4 depth categories (surface drills, 1-meter class drills, 10-meter class drills, and deep drills) has distinct technological profiles and scientific ramifications.     

Experiment LEND of the NASA Lunar Reconnaissance Orbiter for high-resolution mapping of neutron emission of the Moon

The scientific objectives of neutron mapping of the Moon are presented as 3 investigation tasks of NASA's Lunar Reconnaissance Orbiter mission. Two tasks focus on mapping hydrogen content over the entire Moon and on testing the presence of water-ice deposits at the bottom of permanently shadowed craters at the lunar poles. The third task corresponds to the determination of neutron contribution to the total radiation dose at an altitude of 50 km above the Moon. We show that the Lunar Exploration Neutron Detector (LEND) will be capable of carrying out all 3 investigations. The design concept of LEND is presented together with results of numerical simulations of the instrument's sensitivity for hydrogen detection. The sensitivity of LEND is shown to be characterized by a hydrogen detection limit of about 100 ppm for a polar reference area with a radius of 5 km. If the presence of ice deposits in polar "cold traps" is confirmed, a unique record of many millions of years of lunar history would be obtained, by which the history of lunar impacts could be discerned from the layers of water ice and dust. Future applications of a LEND-type instrument for Mars orbital observations are also discussed.     

基于图像的测量方法在工业风洞跨声速流测量中的最新进展

风洞中非定常复杂流场的实验研究要求先进的测量技术.基于图像的测量技术中最重要的是测量平面流速度场、平面压强分布、模型位置和变形、模型温度以及定量的高速流可视化等技术.DLR(德国宇航研究院)对这些技术的应用包括从低速流到跨声速流、从增升装置到螺旋桨和旋翼、从弹射装置和水塔储水罐尾迹流旋涡到三角翼上涡破裂现象等的研究.由于跨声速风洞的特殊环境,将基于图像的测量技术用于跨声速流要求专门的技术开发和有经验的科学家.给出了DLR空气动力学和流动技术研究所将基于图像的测量技术应用于跨声速流研究的最新进展.     

供测量高阻率材料电压、电流和电阻用的前置放大器

本文介绍一种供测量高阻率材料直流电压、电流和电阻用的前置放大器,其测量范围分别为:电压:30μv～10v;电流:10~(-2)～10~(-13)A;电阻:10~3～10~(13)Ω。若在反馈回路中接入适当的电容器还可测量电荷。本前置放大器采用市场上供应的运算放大器制成,其体积较小,并可与市场上大量供应的电压表或记录器联合使用,适用于无定形的(非晶体的)半导体薄膜电气性能的就地测量。