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451.
The dose reduction effects for space radiation by installation of water shielding material (“protective curtain”) of a stack board consisting of the hygienic wipes and towels have been experimentally evaluated in the International Space Station by using passive dosimeters. The averaged water thickness of the protective curtain was 6.3 g/cm2. The passive dosimeters consisted of a combination of thermoluminescent detectors (TLDs) and plastic nuclear track detectors (PNTDs). Totally 12 passive dosimeter packages were installed in the Russian Service Module during late 2010. Half of the packages were located at the protective curtain surface and the other half were at the crew cabin wall behind or aside the protective curtain. The mean absorbed dose and dose equivalent rates are measured to be 327 μGy/day and 821 μSv/day for the unprotected packages and 224 μGy/day and 575 μSv/day for the protected packages, respectively. The observed dose reduction rate with protective curtain was found to be 37 ± 7% in dose equivalent, which was consistent with the calculation in the spherical water phantom by PHITS. The contributions due to low and high LET particles were found to be comparable in observed dose reduction rate. The protective curtain would be effective shielding material for not only trapped particles (several 10 MeV) but also for low energy galactic cosmic rays (several 100 MeV/n). The properly utilized protective curtain will effectively reduce the radiation dose for crew living in space station and prolong long-term mission in the future.  相似文献   
452.
Many students have to choose their future profession during their last years in the high school and therefore to choose a university where they will get proper education. That choice may define their professional life for many years ahead or probably for the rest of their lives.Bauman Moscow State Technical University conducts various events to introduce future professions to high-school students. Such activity helps them to pick specialization in line with their interests and motivates them to study key scientific subjects.The paper focuses on newly developed educational tools to encourage high school students’ interest in STEM disciplines. These tools include laboratory courses developed in the fields of physics, information technologies and mathematics. More than 2000 high school students already participated in these experimental courses. These activities are aimed at increasing the quality of STEM disciplines learning which will result in higher quality of training of future engineers.  相似文献   
453.
A high level of expertise in space policy and law is required to initiate and keep pace with the expansion of space activities, including those undertaken by the private space industry. Space activities generally refer to those undertakings that are carried out with the use of several technologies for the exploration and utilization of outer space often for scientific, military, economic and social proposes within international and national policy and regulatory frameworks. Space policies and legal regimes determine the scope, nature, pace, possibility and development of space undertakings. Therefore, appropriate space policies and regulatory regimes, both at the international and national levels, are indispensable for the initiation, operation and enhancement of space activities. There are various regulatory models and approaches for regulating space activities, and for building capacity in space law and space policy. It is imperative to have the appropriate human resources and capabilities in the development and implementation of space policies and space legal regimes. This crucial requirement has been well recognized in the more advanced space-faring nations, but not to the same level in other space-faring or space-aspiring nations.  相似文献   
454.
俄罗斯的空间军事能力:1992年~2001年   总被引:1,自引:1,他引:1  
在过去的10年间,俄罗斯的各种军用卫星的发射率大幅度降低,甚至出现了没有照相侦察卫星在轨的特殊时期。俄罗斯是否由于财政状况,无法维持其军事空间能力呢?还是另有其他原因呢?文章列举了在1992~2001年间,俄罗斯的军用卫星发射情况,分析了其空间计划的前景。  相似文献   
455.
    
The paper presents the analysis of experimental data on electron fluxes with energies 10 keV–10 MeV. Data were obtained during 1978–2005 years in different space experiments (COSMOS-900, MIR Space Station, ACTIVE, SAMPEX, CORONAS-I, CORONAS-F, NOAA POES-17, TATYANA and others). Two areas of electron flux enhancements are studied in the paper: the near-equatorial (L < 1.2) zone and the middle-latitude (1.2 < L < 1.9) zone. It is shown that electron flux enhancements are regularly registered at L < 2 and the observed formations have some typical features. Electron peaks at L < 1.2 appear sporadically while peaks at 1.2 < L < 1.9 are observed regularly. The approximations of spectra by several functions including kappa-function are presented.  相似文献   
456.
  总被引:1,自引:0,他引:1  
The Meridian Project is a ground- based network program to monitor solar-terrestrial space environment, which consists of a chain of ground-based observatories with multiple instruments including magnetometers, ionosondes, HF and VHF radar, Lidar, IPS monitors, sounding rockets etc. The chain is mainly located in the neighborhood of 120°E meridian, and is thus named the Meridian Project. It has officially been approved by the Chinese government and will be finished by 2009. This talk will give an overview of the Meridian Project and the proposed International Space Weather Meridian Circle Program.  相似文献   
457.
Dietrich Rex   《Space Policy》1998,14(2):95-105
An appraisal of current and future risks from space debris is presented with the aid of calculations carried out by the MASTER model. The efficacy of various technical options -- such as fuel venting, de-orbiting and use of a graveyard orbit -- for counteracting the problem is discussed. The article then focuses on governmental and international cooperative measures and looks at the recent work done by subcommittees of the UN COPUOS.  相似文献   
458.
We report the measurements of the response of a delta-doped Charge Coupled Device (CCD) in imaging mode to beams of charged and neutral particles. That is, the detector imaged the incident beam over its 1024 × 1024 pixels, integrating the number of particles counted in each pixel during the exposure period. In order to count individual particles the exposure time would have had to be reduced considerably compared to the typical ?5 s used in these studies. Our CCD thus operated in a different manner than do conventional particle detectors such as the CEM and MCP that normally are used in a particle counting mode. The measurements were carried out over an energy range from 0.8 to 30 keV. The species investigated include H, H+, He+, N+, N2+, and Ar+. The energy and ion mass covered wider ranges than previous measurements for the CCD. The results of these measurements show, as in the case of the previous measurement, for a given ion the CCD response increases with energy and for a given particle energy the response decreases with increasing mass of the particle. These results are in agreement with predictions of the theory of the range of ions in solids. The results also show the possibility for the application of the delta doped CCD as a detector for low energy particle measurements for space plasma physics applications.  相似文献   
459.
轻型空间相机遮光罩组件的研制   总被引:1,自引:0,他引:1  
文章介绍了空间遥感相机遮光罩的结构特点及其功能。重点介绍了一种用于可见-红外光谱仪上的轻型遮光罩,该仪器安装于2005年美国发射的火星勘测轨道飞行器(MRO)上。  相似文献   
460.
通过温度解算完成相机主体温度测量,是相机主体温控系统实现的关键环节之一.传统的温度解算方法存在数据存储量大、可移植性差、温度映射精度低等缺点.文章提出一种拟合温度解算法,针对不同的系统需求,给出两种改进方案,对拟合温度解算法及其改进方案的原理、性能及实现方式进行描述与分析.实践证明,该方法具有占用内存小、可移植性好、温...  相似文献   
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