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Roberta L Bondar 《Architectural Design》2015,85(4):98-99
‘By 2050 we will have probed the universe even further, peeling back time as we strive for some sense of creation and meaning.’ The world's first neurologist in space, Roberta L Bondar , who conducted international experiments on space mission STS 42 and has subsequently undertaken neurological research with NASA, urges us to look up and into space, which is set to remain a rich area of exploration, scientific investigation and wonder, with the discovery of new planets, light, patterns and materials on the not-so-distant horizon. 相似文献
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支持Web协同的轻量化三维设计框架的研究 总被引:1,自引:0,他引:1
计算机支持的协同设计(Computer Supported Cooperative Design,CSCD)是1种分布式的产品设计和开发模式,为用户提供问题讨论和求解的实时协同环境.基于富客户端技术(Rich Internet Applications,RIA)和JT(Jupiter Tessellation)技术,提出了1种面向中小型企业应用、支持Web协同的轻量化三维设计系统框架,并对系统框架以及关键技术进行了详细阐述.基于该框架,中小型企业能够快速部署基于Web的协同环境,并通过轻量化技术完成三维模型的转化,以适应同步协同设计的需要.最后,原型系统验证了轻量化三维设计的有效性,为协同设计领域的应用提供了一定的借鉴意义. 相似文献
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木星极光区为极光电子注入等离子体环境,是木星轨道航天器表面充电典型恶劣环境。基于木星磁层等离子体模型DG1/DG2,系统论述了木星极光区等离子体环境及其特征;通过理论研究认为,在仿真计算和地面模拟试验评估木星航天器表面充电水平时,对于木星极光区等离子体环境,可以采用背景等离子体加极光电子的双麦克斯韦分布模型来近似。利用兰州空间技术物理所的“空间等离子体充放电效应模拟设备”及其测试平台,模拟木星极光区的麦克斯韦分布入射极光电子流(特征能量为25 keV)及其束流强度(0.02~0.08 nA/cm2),开展了木星航天器常用表面材料ITO-OSR、CFRP和CERS表面充放电效应地面模拟试验研究。研究表明,在木星极光区环境条件下,航天器常用表面材料CFRP与ITO-OSR间、CFRP与CERS间均存在着静电放电风险。研究为我国未来木星航天器研制及其充放电效应防护提供了设计依据和试验基础。 相似文献
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桑托斯盆地Jupiter油气田油气藏中富含CO2,气层与油层流体成分存在明显差异,油气藏相态及形成机理没有取得共识。采用四参数方框图法、流体组分三角图、φ1值、Z1以及Z2等多参数法对Jupiter油气藏相态进行综合判识,认为Jupiter油气藏为带油环凝析气藏。油气藏中凝析油与原油具有相似的分子地球化学特征,Pr/Ph比值为1.58~1.88,C26三环萜烷/C25三环萜烷比值为1.15~1.22,甾烷以C27甾烷占优势,藿烷/甾烷比值大于4, TPP比值大于0.5,全油碳同位素在-25‰左右。地球化学参数说明二者来源于白垩系Upper Barremian-Lower Aptian阶湖湘烃源岩。凝析油与原油具有相似的成熟度,均为生烃高峰的产物。烷烃气来自于Upper Barremian-Lower Aptian阶湖湘烃源岩,为生烃高峰——凝析油前期阶段的产物。CO2为火山幔源型CO2,大量CO2后期注入形成的蒸发分馏作用,对早期形成的油气藏进行改造,形成了现今带油环凝析气藏的面貌。地球化学参数证实了蒸发分馏作用的存在,无机CO2的注入丰富了蒸发分馏作用理论。 相似文献
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阐述了以Jupiter OEM板为核心的GPS接收机的软硬件设计,采用芯片SP2339实现了串口的硬件扩展,使用以ST7920为核心控制芯片的12864液晶屏显示接收到的数据,在嵌入式程序中使用单向链表完成数据的存储处理,设计完成的GPS接收机能够快速定位、测量野外站点坐标. 相似文献
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JupiterPlus电能质量分析仪是由意大利Elcontrol Energy NetS.p.A.公司生产的计算机辅助检测系统,包括现场测试仪器Jupiter Plus和智能分析软件PQStudio。Jupiter Plus系统能直接测出电梯的用电情况和回馈装置的馈电情况,还可以检测回馈到电网的电能质量问题,如电压波动、频率扰动、谐波/间谐波、电压不平衡、电压中断等多项参数,并可通过曲线图表对测量过程进行显示和分析。 相似文献
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Francis F. Badavi Steve R. Blattnig 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(3):232-238
A Langley research center (LaRC) developed deterministic suite of radiation transport codes describing the propagation of electron, photon, proton and heavy ion in condensed media is used to simulate the exposure from the spectral distribution of the aforementioned particles in the Jovian radiation environment. Based on the measurements by the Galileo probe (1995-2003) heavy ion counter (HIC), the choice of trapped heavy ions is limited to carbon, oxygen and sulfur (COS). The deterministic particle transport suite consists of a coupled electron photon algorithm (CEPTRN) and a coupled light heavy ion algorithm (HZETRN). The primary purpose for the development of the transport suite is to provide a means to the spacecraft design community to rapidly perform numerous repetitive calculations essential for electron, photon, proton and heavy ion exposure assessment in a complex space structure. In this paper, the reference radiation environment of the Galilean satellite Europa is used as a representative boundary condition to show the capabilities of the transport suite. While the transport suite can directly access the output electron and proton spectra of the Jovian environment as generated by the jet propulsion laboratory (JPL) Galileo interim radiation electron (GIRE) model of 2003; for the sake of relevance to the upcoming Europa Jupiter system mission (EJSM), the JPL provided Europa mission fluence spectrum, is used to produce the corresponding depth dose curve in silicon behind a default aluminum shield of 100 mils (∼0.7 g/cm2). The transport suite can also accept a geometry describing ray traced thickness file from a computer aided design (CAD) package and calculate the total ionizing dose (TID) at a specific target point within the interior of the vehicle. In that regard, using a low fidelity CAD model of the Galileo probe generated by the authors, the transport suite was verified versus Monte Carlo (MC) simulation for orbits JOI-J35 of the Galileo probe extended mission. For the upcoming EJSM mission with an expected launch date of 2020, the transport suite is used to compute the depth dose profile for the traditional aluminum silicon as a standard shield target combination, as well as simulating the shielding response of a high charge number (Z) material such as tantalum (Ta). Finally, a shield optimization algorithm is discussed which can guide the instrument designers and fabrication personnel with the choice of graded-Z shield selection and analysis. 相似文献
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为了实现中国深空探测器能够以对日极轨方式,从黄道外的太阳两极观测日冕爆发与太阳磁场四维活动等,分析了Ulysses探测器的运载发射入轨方案,研究了借力飞越木星引起探测器在太阳系内速度矢量的变化规律,给出了运载火箭入轨速度与木星借力后能够实现的最大黄道夹角理论分析方法,优化了新一代长征运载火箭发射借力木星高纬度观测太阳探测器时,需要的运载火箭新增上面级性能状态,并给出了飞行轨道具体分析算例对比。 相似文献
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