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MARS

MARS的相关文献在1989年到2022年内共计239篇,主要集中在自动化技术、计算机技术、内科学、无线电电子学、电信技术 等领域,其中期刊论文190篇、会议论文10篇、专利文献39篇;相关期刊153种,包括科学时代、国际护理学杂志、中国血液净化等; 相关会议3种,包括第三届国际暨全国肝衰竭与人工肝学术会议、第一届全国人工肝及血液净化学术年会暨全国人工肝及血液净化攻关协作组成立大会、中华医学会第二届全国暨国际肝衰竭与人工肝学术会议等;MARS的相关文献由407位作者贡献,包括史宇飞、张成海、张玉晶等。

MARS—发文量

期刊论文>

论文:190 占比:79.50%

会议论文>

论文:10 占比:4.18%

专利文献>

论文:39 占比:16.32%

总计:239篇

MARS—发文趋势图

MARS

-研究学者

  • 史宇飞
  • 张成海
  • 张玉晶
  • 朱玲巧
  • 杨小兰
  • 杨毅军
  • 王立蓉
  • 王芝花
  • 高宏海
  • Alexander Rubinraut
  • 期刊论文
  • 会议论文
  • 专利文献

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    • YaoKun Li; JiPing Chao
    • 摘要: A two-dimensional energy balance climate model has been built to investigate the climate on Mars.The model takes into account the balance among solar radiation,longwave radiation,and energy transmission and can be solved analytically by Legendre polynomials.With the parameters for thermal diffusion and radiation processes being properly specified,the model can simulate a reasonable surface atmospheric temperature distribution but not a very perfect vertical atmospheric temperature distribution compared with numerical results,such as those from the Mars Climate Database.With varying solar radiation in a Martian year,the model can simulate the seasonal variation of the air temperature on Mars.With increasing dust content,the Martian atmosphere gradually warms.However,the warming is insignificant in the cold and warm scenarios,in which the dust mixing ratio varies moderately,whereas the warming is significant in the storm scenario,in which the dust mixing ratio increases dramatically.With an increasing albedo value of either the polar cap or the non-ice region,Mars gradually cools.The mean surface atmospheric temperature decreases moderately with an increasing polar ice albedo,whereas it increases dramatically with an increasing non-ice albedo.This increase occurs because the planetary albedo of the ice regions is smaller than that of the non-ice region.
    • Fred J. Cadieu
    • 摘要: Correlations between the rotations of the terrestrial planets in our solar system and the magnetic field of the Sun have been previously noted. These correlations account for the opposite rotation of Venus as a result of the magnetic field of the Sun being dragged across the conducting core of Venus. Currently, the Sun’s magnetic field is not sufficiently strong to account for the proposed correlations. But recently meteorite paleomagnetism measurements have indicated that during the Sun’s formation the magnetic field of the Sun was of sufficient strength to have resulted in the observed correlations. Also, dating back to the Sun’s formation are measurements showing that the Sun’s core rotates four times faster than the Sun’s surface. Both the counter rotation of Venus and the initial period of strong Sun magnetic fields are believed to be relics of the time period when the Sun’s core to surface differential rotation was established. As a part of these correlations, it was hypothesized that for a terrestrial planet to exhibit a magnetosphere, the average density must be ≥5350 ± 50 kg/m3. On this basis, only the Earth and Mercury would have formed initial magnetospheres, while Venus, Mars, and the “Moon” would not have developed magnetospheres. For such correlations to still be present today requires our Sun to have been formed as a sole star and with what might be termed a friendly Jupiter. Otherwise, the observed correlations would have been disrupted over time.
    • 余红玲; 王晓玲; 王成; 曾拓程; 余佳; 盖世聪
    • 摘要: 渗流参数贝叶斯反演的关键在于解决对渗流正演模型大量调用而导致的计算耗时问题。现有提高贝叶斯反演计算效率的研究大多采用基于单一机器学习算法的代理模型,计算精度较低。针对上述问题,本文提出一种贝叶斯框架下大坝渗流参数反演组合代理模型。该方法在贝叶斯框架下集成支持向量回归(SVR)、Kriging和多元自适应回归样条(MARS)三种机器学习算法。其中,利用差分进化自适应Metropolis(DREAMZS)算法并行采样的优势计算权重系数的随机分布函数,在考虑不确定性的条件下获得模型权重系数。案例分析表明,相比于运行一次至少需要耗费4 h的渗流数值模型,本文所提组合代理模型运行一次仅需几秒钟,显著提高了贝叶斯反演的计算效率;此外,本文所提反演方法相比于基于SVR、Kriging和MARS的贝叶斯反演方法能够获得更准确的反演结果,其平均精度分别提高了13.78%、19.34%和12.27%,为大坝渗流参数反演提供了一种新思路。
    • D.Singh; S.Uttam
    • 摘要: For planetary surface materials,thermal inertia is the critical property that governs the surface’s daily thermal response and controls diurnal and seasonal surface temperature variations.Here we use the ground measurements made by the MSL Curiosity rover and the InSight lander to determine the thermal inertia of two sites on Mars.This study compares the variation of thermal inertia during and after the Large Dust Storm(LDS)of Martian Year(MY)34.To determine surface thermal inertia,we derive a simple approximation(using energy balance),which utilizes surface albedo,surface energy flux,and diurnal change in the surface temperature.The average thermal inertia in MY34 is about 39.2%,3.7%,and 3.4%higher than MY35 average thermal inertia for the MSL,InSight(FOV1),and InSight(FOV2),respectively.Notably,the thermal inertia at the InSight(FOV1)is consistently lower by about 20 J·m^(-2)·s^(-1/2)·K^(-1) than the InSight(FOV2)site for all scenarios,indicating variation in the region’s surface composition.The best-fit surface albedo in MY34(determined using the KRC model)are about 0.08,0.05,and 0.03 higher than MY35 surface albedo for the MSL,InSight(FOV1),and InSight(FOV2),respectively.An increase in both surface albedo and thermal inertia during the LDS indicates that the underlying surface is both more thermally resistant and more reflective than the overlying loose dust.
    • Mohsin Usman Qureshi; Zafar Mahmood; Ali Murtaza Rasool
    • 摘要: The assessment of in situ permeability of rock mass is challenging for large-scale projects such as reservoirs created by dams,where water tightness issues are of prime importance.The in situ permeability is strongly related to the frequency and distribution of discontinuities in the rock mass and quantified by rock quality designation(RQD).This paper analyzes the data of hydraulic conductivity and discontinuities sampled at different depths during the borehole investigations in the limestone and sandstone formations for the construction of hydraulic structures in Oman.Cores recovered from boreholes provide RQD data,and in situ Lugeon tests elucidate the permeability.A modern technique of multivariate adaptive regression splines(MARS)assisted in correlating permeability and RQD along with the depth.In situ permeability shows a declining trend with increasing RQD,and the depth of investigation is within 50 m.This type of relationship can be developed based on detailed initial investigations at the site where the hydraulic conductivity of discontinuous rocks is required to be delineated.The relationship can approximate the permeability by only measuring the RQD in later investigations on the same site,thus saving the time and cost of the site investigations.The applicability of the relationship developed in this study to another location requires a lithological similarity of the rock mass that can be verified through preliminary investigation at the site.
    • 赵蒙蒙
    • 摘要: 目的 观察人工肝血浆置换联合分子吸附循环系统(MARS)治疗重症肝炎的效果.方法 将收治的82例重症肝炎的患者按随机数字表法分为观察组和对照组各41例.两组均予重症肝炎对症处理,在此基础上两组均使用人工肝血浆置换技术治疗,观察组加用MARS.比较两组疗效及治疗前后肝功能、凝血功能、炎症细胞因子水平的变化,记录两组治疗期间不良反应发生状况.结果 观察组总有效率高于对照组,丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、总胆红素(TBIL)较对照组低,PT较对照组短,凝血酶原活动度(PTA)高于对照组;观察组炎症细胞因子水平低于对照组.结论 人工肝血浆置换联合MARS可通过减轻患者炎症反应,通过改善肝功能及凝血功能等途径提高重症肝炎患者治疗效果,改善病情.
    • DONG Jie; SUN Zezhou; RAO Wei; DONG Tianshu
    • 摘要: The environmental conditions of Mars landing missions are much different from that of Earth reentry missions, including the distance between the spacecraft and the Earth, the atmosphere, landform, aerodynamic forces, thermal effects. Therefore there are more autonomy requirements, more flight phases, more uncertainties in modeling and analysis, and more difficulties in validation of the flight sequence. Firstly the challenges of Mars landing missions are summarized in this paper. Then the key issues for Mars landing missions are analyzed according to the phases of the landing process. Finally suggestions and proposals for further development for Mars landing technologies are given.
    • 摘要: 2020年是火星探测器发射的最佳窗口期。世界各国都在等待着这次火星探测的狂欢。目前的主角有三个:中国的“天问一号”、美国的“毅力号”、阿联酋与日本合作的“希望号”。遗憾的是,这个“三缺一”的局面原本还存在一个小伙伴——欧洲“ExoMARS2020”。但是由于它的降落伞系统不过关,导致这个已经推迟了三次的欧洲火星探测器不得不再次推迟,变为“ExoMARS2022”。
    • 邹钰
    • 摘要: 新技术的发展,为建筑行业带来了新的生机,在建筑表现中先使用SketchUp软件进行三维建模,再利用Mars软件的良好交互性和VR功能进行建筑表现,不但可以节约成本,而且可以大大提高设计和沟通效率,真正可以做到将设计回归本源,把工作交给科技.
    • Alexander Rubinraut
    • 摘要: A project of spacecraft “moonplane” for regular delivery of astronauts onto the Moon is considered. At the first stage of flight by using a carrier rocket, equipped with a chemical rocket engine, the astronauts are delivered on the international space station ISS. For flights from Earth orbit into Moon orbit, the design of a moonplane “MOND”, consisting of an interorbital module and a lunar module, has been developed. The interorbital module is an electric rocket, equipped with four superconductive magnetoplasma engine MARS. To power supply of the electromotors, a solar battery of gallium arsenide is used. The design of the lunar module with cabin astronauts, which is equipped with a chemical rocket engine for landing and take-off from the surface of the Moon, is developed. A method and a device for refuelling of the electrical rocket engines with nitrogen and for refuelling of the chemical rocket engines with oxygen and hydrogen, which are stored in cryogenic tanks of the moonplane in the liquid state is developed. The developed spacecraft is capable to regularly transport four astronauts off a moorage of ISS onto the surface of the Moon and back during 6 days. The total cost delivery of one astronaut is 4 million US dollars.
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