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The multiparametric dosimetry system that we are developing for medical radiological defense applications could be adapted for spaceflight environments. The system complements the internationally accepted personnel dosimeters and cytogenetic analysis of chromosome aberrations, considered the best means of documenting radiation doses for health records. Our system consists of a portable hematology analyzer, molecular biodosimetry using nucleic acid and antigen-based diagnostic equipment, and a dose assessment management software application. A dry-capillary tube reagent-based centrifuge blood cell counter (QBC Autoread Plus, Becton [correction of Beckon] Dickinson Bioscience) measures peripheral blood lymphocytes and monocytes, which could determine radiation dose based on the kinetics of blood cell depletion. Molecular biomarkers for ionizing radiation exposure (gene expression changes, blood proteins) can be measured in real time using such diagnostic detection technologies as miniaturized nucleic acid sequences and antigen-based biosensors, but they require validation of dose-dependent targets and development of optimized protocols and analysis systems. The Biodosimetry Assessment Tool, a software application, calculates radiation dose based on a patient's physical signs and symptoms and blood cell count analysis. It also annotates location of personnel dosimeters, displays a summary of a patient's dosimetric information to healthcare professionals, and archives the data for further use. These radiation assessment diagnostic technologies can have dual-use applications supporting general medical-related care.  相似文献   
2.
Ms. Smith, associate administrator for commercial space transportation within the Federal Aviation Administration, answers questions about regulations and licensing related to reusable launch vehicles, space passenger vehicles, and commercial space ventures.  相似文献   
3.
To meet the size/performance and cost-driven goals required for more advanced projectile and mortar applications, IEC focused its efforts on function consolidation, electronic signal protection, ultra-deep sensor integration, and processing stability. IEC's development has been in the utilization of silicon-based micro-machine technology for the inertial sensor, high levels of processor integration, and hardware function consolidation, making the guidance package inherently immune to the vibration and high G shock effects of the launch. In addition, the size and power are sufficiently reduced to fit the constraints of the fuse well. While a GPS “only”-based guidance system seemed an ideal solution for the lowest cost implementation of smart weapon guidance, the potential for signal jamming meant that a GPS “only” solution would not be able to guide the projectile to the target. To resolve this limitation, an anti-jam (AJ) capability had to be incorporated into the GPS receiver, and a miniature on-board inertial measurement unit (IMU) had to be part of the system. Initial laboratory tests have proven that the GPS/inertial guidance system, enhanced with a robust, low-cost AJ subsystem, performs consistently well under simulated battlefield conditions  相似文献   
4.
问:2010上海世博会是全球关注的一大盛事,阁下对明年的上海世博会有什么感言?答:上海2010年世博会将会是一场由世界各地知识技术荟萃而成的奇幻盛展。"城市,让生活更美好"这个主题对世界上已逾一半生活在城市里的人们来说是非常符合现实的。无论是在上海,赫尔辛基,还是在世界其他城市,我们都需要为市民创造出一个健康幸福的  相似文献   
5.
世博会中的芬兰:建筑、设计和创造力芬兰一直是世界博览会积极的参与者。从第一届1851年伦敦世博会开始就已开始崭露头角,虽然当时作为俄国的一部分(芬兰  相似文献   
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This paper describes a multidisciplinary research project which seeks to characterize the terrestrial water cycle and use this characterization to derive simulations of carbon dioxide and methane flux. The water cycle work links interpolated climate fields, macrohydrologic models and Scanning Multichannel Microwave Radiometer datasets. The aim of the analysis is to use output from calibrated water balance models to develop relationships with SMMR datasets. SMMR estimates of surface hydrology can then be evaluated. Both modeled and SMMR datasets will be tested as inputs to regional biogeochemical models. All determinations will be made under climatically-averaged conditions and for 1979–1985, the years for which SMMR data is available.  相似文献   
7.
This paper describes an algorithm which protects a three-gimballed inertial system against gimbal lock while preserving the inertial reference. One sample of the gimbal angles and gimbal angle rates for a torque-free dynamic vehicle provides the information needed to determine whether or not gimbal lock will occur at some later time. When gimbal lock is imminent, the inertial platform is commanded to a new "safe" orientation, and knowledge of the inertial reference is updated accordingly. By iterating this process gimbal lock protection is extended to a vehicle subjected to torques. The results of digital simulations using the Apollo Primary Guidance, Navigation and Control System as a model are presented for various dynamic situations.  相似文献   
8.
Barraclough  B.L.  Dors  E.E.  Abeyta  R.A.  Alexander  J.F.  Ameduri  F.P.  Baldonado  J.R.  Bame  S.J.  Casey  P.J.  Dirks  G.  Everett  D.T.  Gosling  J.T.  Grace  K.M.  Guerrero  D.R.  Kolar  J.D.  Kroesche  J.L.  Lockhart  W.L.  McComas  D.J.  Mietz  D.E.  Roese  J.  Sanders  J.  Steinberg  J.T.  Tokar  R.L.  Urdiales  C.  Wiens  R.C. 《Space Science Reviews》2003,105(3-4):627-660
The Genesis Ion Monitor (GIM) and the Genesis Electron Monitor (GEM) provide 3-dimensional plasma measurements of the solar wind for the Genesis mission. These measurements are used onboard to determine the type of plasma that is flowing past the spacecraft and to configure the solar wind sample collection subsystems in real-time. Both GIM and GEM employ spherical-section electrostatic analyzers followed by channel electron multiplier (CEM) arrays for detection and angle and energy/charge analysis of incident ions and electrons. GIM is of a new design specific to Genesis mission requirements whereas the GEM sensor is an almost exact copy of the plasma electron sensors currently flying on the ACE and Ulysses spacecraft, albeit with new electronics and programming. Ions are detected at forty log-spaced energy levels between ∼ 1 eV and 14 keV by eight CEM detectors, while electrons with energies between ∼ 1 eV and 1.4 keV are measured at twenty log-spaced energy levels using seven CEMs. The spin of the spacecraft is used to sweep the fan-shaped fields-of-view of both instruments across all areas of the sky of interest, with ion measurements being taken forty times per spin and samples of the electron population being taken twenty four times per spin. Complete ion and electron energy spectra are measured every ∼ 2.5 min (four spins of the spacecraft) with adequate energy and angular resolution to determine fully 3-dimensional ion and electron distribution functions. The GIM and GEM plasma measurements are principally used to enable the operational solar wind sample collection goals of the Genesis mission but they also provide a potentially very useful data set for studies of solar wind phenomena, especially if combined with other solar wind data sets from ACE, WIND, SOHO and Ulysses for multi-spacecraft investigations. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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