Observation of Transition Region Fine Structures with Soho/Sumer

We present a preliminary analysis of two quiet Sun transition region areas observed with the SOHO/SUMER spectrometer, using lines from oxygen, nitrogen and silicon. The average quiet Sun physical parameters are studied as a function of line intensity. Systematic variations of line position and width with increasing intensity are found. A large number of small-scale active points have been observed, and preliminary analysis of the physical properties and dynamics of these active features is presented. A jet-like structure, found in an active point, is also investigated and its velocity along the line of sight determined. This revised version was published online in June 2006 with corrections to the Cover Date.     

Quiet sun XUV and EUV spectroscopy

The two XUV–EUV spectrometers on SOHO have collected a large amount of data in the 6000–10⁶ K solar plasma temperature range. These data have allowed us to greatly enhance our knowledge of the processes acting in the solar atmosphere, from the chromosphere to the corona. Some results on the quiet Sun structure (network, quiet Sun versus coronal hole), on the dynamics (velocities, waves, transient events), and the main characteristics of the quiet Sun atmosphere are presented and discussed.     

Magneto-gravity Waves Trapped in the Lower Solar Corona

The possibility of trapped magneto-gravity waves in the lower solar corona with an open magnetic field is discussed. Intensity variations and/or Doppler shifts of relevant UV, EUV and x-ray spectral lines in the chromosphere, transition region and lower corona may reveal the existence of such low-frequency modes (with periods longer than ∼ 1.5 hour). The spectrum may be either discrete or continuous depending on the reflection property of the narrow transition region. These modes can be utilized to probe the dynamics of the upper chromosphere, transition region and lower corona; they may also play an important role in coronal heating. This revised version was published online in June 2006 with corrections to the Cover Date.     

太阳活动、黑潮海温年季变化与长江中游旱涝灾害

本文采用太阳１０．７ｃｍ辐射流量（Ｆ１０．７）作为太阳活动指标，根据最近３０多年的太阳活动、西太平洋黑潮区海温和长江中游干支流地区雨量观测数据，分析了三者之间的关系，研究发现长江中游地区旱涝明显地受太阳活动和黑潮海温年季变化的共同控制．可根据某些特征，利用两年之前的太阳１０．７ｃｍ辐射流量和当年春季之前黑潮海温的观测数据，分析判断长江中游当年夏季是否发生旱涝灾害的趋势．     

基于投影寻踪的地磁匹配区选取方法

针对基于单一地磁特征参数进行区域选取容易出现评价结果不全面的缺陷,提出了多特征参数融合的地磁匹配区选取方法。该方法结合信息熵和投影寻踪理论,综合考虑地磁标准差、粗糙度、相关系数和地磁熵等反映特定区域内地磁的总体起伏、光滑度、相关性强弱和信息量多少的地磁特征参数对匹配区的影响,建立了基于投影寻踪的地磁匹配区选取模型,利用遗传算法求解出最优投影方向,给出区域总的评价指数。利用文中提出的方法在选定区域进行了仿真试验,仿真结果表明,针对ICCP算法,在总评价指标高的区域进行地磁辅助导航,其匹配误差较小。
     

TA15 钛合金等温局部加载各加载区的组织和性能

研究了不同加载方式下TA15钛合金方坯先加载区、过渡区和后加载区的组织和力学性能。结果表明:只采用局部加载时,先加载区和后加载区的室温和高温性能优于过渡区的性能,各区的持久性能差别不大;采用先局部后整体的加载方式时,过渡区的室温和高温性能优于其他两个加载区,但过渡区的持久性能明显较差。只采用局部加载时,各区的组织性能优于先局部后整体加载时各区的组织性能。     

需求信息共享供应链系统稳定域内的优化

考虑由分销商和制造商构成的需求信息共享的二级供应链系统,通过考察系统参数对系统稳定性的影响,确定系统的稳定域;建立系统的3个稳定性指标,利用最优化理论及多目标优化算法NSGA-Ⅱ在系统稳定域内搜索实现系统最优状态的参数组合,这些最优解能使系统的3个稳定性指标达到Pareto最优,即不可能改善某一个稳定性指标,而不使其他指标受损.通过仿真实验确定系统在不同提前期参数取值情况下的最优稳定性指标值和相应的参数组合,研究在稳定域内系统参数对系统最优状态下3个系统指标的影响.根据研究结果提出了旨在提高供应链运行稳定性及稳定状态下寻找最优系统状态的管理学建议.     

Method of stability region determination for planetary gear train＇s parameters based on nonlinear vibration model

研究了行星齿轮非线性传动系统参数稳定域计算的一般方法.该方法通过选取合理的失稳阀值,根据考查参数域内系统的运动状态选取合适的数值积分时间段,以循环套嵌的手段计算考查参数在各自范围内不同组合下的系统位移响应最大值,比较失稳阀值以判稳,参数稳定域的图形输出等5个步骤完成对行星轮系参数稳定域的计算.最后,以四自由度行星轮系纯扭转非线性振动模型为例,以行星轮输入转速、系统的齿侧间隙以及齿轮副的啮合阻尼系数为考查参数,分别计算得到了系统的单参数稳定域、双参数稳定域以及三参数稳定域,为行星轮系的设计取值提供了重要参考.     

长波授时附加二次相位因子ASF误差分析

为提高长波授时精度,分析了影响ASF误差的因素。主要针对米林顿法计算ASF中的地图测距误差、大地等效电导率误差和大地等效电导率区域分割误差,设计实验、采集数据、分析实验结果,并提出减小ASF误差的新方案。     

Actors of the main activity in large complex centres during the 23 solar cycle maximum

During the maximum of Solar Cycle 23, large active regions had a long life, spanning several solar rotations, and produced large numbers of X-class flares and CMEs, some of them associated to magnetic clouds (MCs). This is the case for the Halloween active regions in 2003. The most geoeffective MC of the cycle (Dst = −457) had its source during the disk passage of one of these active regions (NOAA 10501) on 18 November 2003. Such an activity was presumably due to continuous emerging magnetic flux that was observed during this passage. Moreover, the region exhibited a complex topology with multiple domains of different magnetic helicities. The complexity was observed to reach such unprecedented levels that a detailed multi-wavelength analysis is necessary to precisely identify the solar sources of CMEs and MCs. Magnetic clouds are identified using in situ measurements and interplanetary scintillation (IPS) data. Results from these two different sets of data are also compared.