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21.
A problem of determining the stressed state of the thin-walled beam in the zone of deplanation constraint caused by a torque discontinuity is considered using Odinokov’s formulation of mutually-balanced end loading.  相似文献   
22.
利用PIV法对硅油液桥热毛细对流的定常速度场进行了实时测量。为了便于测量,液桥上桥端面采取了铜环中嵌透明材料的方法,从液桥的顶部进行观测。当液桥上下桥有温差时,热毛细对流出现;本实验对于不同上下桥的温差,对液桥横剖面内的速度场分别进行了测量,研究外加温差对于流场速度分布的影响;并且在液桥中取了几个典型横截面进行测量,以期对大Pr数液桥的定常速度场有比较全面的定量测量。此外,实验结果也可作为数值模拟计算结果的验证。  相似文献   
23.
The motion of blades relative to the disk wing at the extension and retraction modes is defined. The general solution is obtained including the fuselage motion under the action of control or external disturbance.  相似文献   
24.
The paper considers some theoretical aspects of implementing the semi-passive homing method for mobile objects by an example of radar-based systems.  相似文献   
25.
Hourly values of the F2-layer peak density, NmF2, measured by 62 ionosonde stations from 1957 to 2008 at middle geomagnetic latitudes of the northern and southern hemispheres are used in a statistical study of the F2-region winter anomaly. We analyze a maximum value, R, of the winter/summer geomagnetically quiet daytime NmF2 ratio over each ionosonde for approximately the same winter and summer solar activity conditions. The conditional probability of an occurrence of R in an interval of R, the most frequent value of R, the mean expected value of R, and the conditional probability to observe the F2-region winter anomaly are calculated and studied for low, moderate, and high solar activity conditions. It is found that northern hemisphere stations show significant cross-correlations of winter anomaly statistics with geomagnetic latitude for moderate and high solar activities.  相似文献   
26.
A brief review of observations is given of cyclotron features of radiation from degenerated stars. Explanations of these data and predictions of new observational effects are proposed on the basis of theoretical results presented in Paper I.  相似文献   
27.
An empirical formula relating the strength of a storm given by its |Dst|max with the L-coordinate of the peak of storm-injected relativistic electrons is one of a few well-confirmed quantitative relations found in the magneto-spheric physics. We successively extended a dataset of the formula’s basic storms with several events of high Dst-amplitude up to the highest observed |Dst|max = 600 nT. Possible applying of the formula to the predicting of the ring-current plasma-pressure distribution and the lowest westward electrojet position for a storm are discussed. We have also analyzed the 2000–2001 years’ data on relativistic electrons from our instruments installed on EXPRESS-A (geosynchronous orbit; Ee = 0.8–6 MeV), Molniya-3 (h = 500 × 40 000 km, i = 63°; Ee = 0.8–5.5 MeV) and GLONASS (h = 20 000 km, i = 64°; Ee  l MeV) along with other correlated measurements: GOES series (Ee > 2 MeV), geomagnetic indices (Dst, AE, AL) and interplanetary parameters (solar wind, IMF). The goal is to investigate which outer conditions are most responsible for the high/low output of the storm-injected relativistic electrons. For the geosynchronous orbit, two factors are found as the necessary condition of the highest electron output: high and long-lasting substorm activity on a storm recovery phase and high velocity of solar wind. On the contrary, extremely low substorm activity surely observed during whole the storm recovery phase constitutes a sufficient condition of the non-increased after-storm electron intensity. For the first time found cases of the increased after-storm electron intensity observed at the inner L-shells with no simultaneously seen increase in the geosynchronous distances are presented.  相似文献   
28.
A composite structure consisting of a lifting surface and a controlling one hinged to it at three and more points is considered. Influence of the controlling surface incidence on dynamic reactions in the attachment fittings is analyzed. Two variable-rigidity rods joined in the attachment fittings are used as a calculation scheme. The dynamic problem is solved with the use of the Newmark method.  相似文献   
29.
The dynamics of near plasma sheet electrons and ions (E 0.1–12.4 keV), ring current protons (E i 41–133 keV), and energetic electrons from the Earth's radiation belts (E e 97–1010 keV) is considered using the data from the Gorizont-34and Gorizont-35geosynchronous satellites from March 11–25, 1992. Peculiarities of this period are a long (more than 4 days) interval of the northward interplanetary magnetic field (B z> 0) and a high-speed stream of the solar wind with an enhanced particle density. The SC and compression of the magnetosphere to the geosynchronous orbit (GMC) preceded this interval. Under quiet and moderately disturbed geomagnetic conditions and under a prolonged northward interplanetary magnetic field, we observed a significant decrease of fluxes and softening of spectra of the electron component of plasma in the energy ranges of 0.1–12.4 keV and 97–1010 keV, and of the ion component of plasma at energies of 0.1–4 keV, while the intensity of 5–12.4 keV ion fluxes increases by about one order of magnitude. The peculiarities of distributions of energetic particle fluxes observed in the period under consideration can be associated with significant variations of the convection conditions and a decreased or fully suppressed injection of energetic electrons into the geosynchronous orbit region.  相似文献   
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