Calculation of the transonic dip of airfoils using viscous-inviscid aerodynamic interaction method

A numerical procedure for the calculation of the transonic dip of airfoils in the time domain is presented. A viscous-inviscid aerodynamic interaction method is taken to calculate the unsteady aerodynamic loads. In the present case the integral boundary layer equations are coupled with the Transonic Small Disturbance (TSD) Potential Equation. The coupling between structural motion and aerodynamic loads is carried out using State Space equation. It is solved by State Transition Matrix technique. Results are presented for NACA 64A010 and NLR 7301 airfoils with structural data from Isogai and DLR, respectively. Comparisons show good agreement with other numerical results. Certain deviations of experimental data taken from literature need more insight in the detailed test conditions.     

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with primary goat embryonic fibroblast showed no difference from traditional feederlayer-based culture method used in mouse and human. The putative primary EG colonies were multilayer clumps ofcompact cel     

现场动平衡技术在生产中的应用

利用美国恩泰克公司提供的DP1500数据采集仪及现场动平衡软件,以实例说明了现场动平衡技术在锅炉引风机、排粉风机、电动机、机泵等转动设备不平衡故障排除中的应用,介绍了不平衡故障的识别方法,揭示出该技术在生产中的实用性、先进性和经济性.     

电液位置伺服系统的动态试验研究

本文研究了快速响应的电液位置伺服系统动态试验,着重讨论了在实践中如何选择伪随机二位式最大长度序列(PRBS)参数的问陋,并提出快速响应系统PRBS参数选择的原则,使系统辨识精度提高约15％。     

卫星推进及控制装置准直测量方法研究

在传统的卫星推进及控制装置准直测量方法的基础上,提出两种新的测量方法,即小角度准直测量法和三维坐标准直测量法,并给出了相应的数据处理方法。所提出的方法测量精度高、测量速度快,无需转台整平,也不必对转台上的定位销进行精确准直。     

质量矩导弹的神经网络及自适应非线性控制

本文对质量矩控制导弹的动力学方程简化和控制系统的设计进行了研究。详细阐述了所提出的控制方法，介绍了径向基单隐层神经网络进行误差补偿的算法原理，用Lyapunov理论证明了所采用方法的稳定性。在给出了质量矩导弹的六自由度动力学方程和简化后的方程后，用所提出的方法设计控制系统。通过仿真分析，得出了本文所提出的方法具有较好的误差补偿能力的结论。     

What Determines the Composition of SEPs in Gradual Events?

Gradual solar energetic particle (SEP) events are evidently accelerated by coronal/interplanetary shocks driven by coronal mass ejections. This talk addresses the different factors which determine the composition of the accelerated ions. The first factor is the set of available seed populations including the solar wind core and suprathermal tail, remnant impulsive events from preceding solar flares, and remnant gradual events. The second factor is the fractionation of the seed ions by the injection process, that is, what fraction of the ions are extracted by the shock to participate in diffusive shock acceleration. Injection is a controversial topic since it depends on the detailed electromagnetic structure of the shock transition and the transport of ions in these structured fields, both of which are not well understood or determined theoretically. The third factor is fractionation during the acceleration process, due to the dependence of ion transport in the turbulent electromagnetic fields adjacent to the shock on the mass/charge ratio. Of crucial importance in the last two factors is the magnetic obliquity of the shock. The form of the proton-excited hydromagnetic wave spectrum is also important. Finally, more subtle effects on ion composition arise from the superposition of ion contributions over the time history of the shock along the observer’s magnetic flux tube, and the sequence of flux tubes sampled by the observer.     

Broad-band spectral properties of accreting X-ray binary pulsars

Broad-band spectra of accreting X-ray binary pulsars can be fitted by a phenomenological model composed of a power law with a high energy rollover above 10 keV, plus a blackbody component with a temperature of few hundred eV. While, at least qualitatively, the hard tail can be explained in terms of (inverse) Compton scattering, the origin of the soft component cannot find a unique explanation. Recently, a qualitative picture able to explain the overall broad-band spectrum of luminous X-ray pulsars was carried out by taking into account the effect of bulk Comptonization in the accretion column. After a review of these recent theoretical developments, I will present a case study of how different modeling of the continuum affect broad features, in particular the cyclotron resonance features in Vela X-1.     

The double-pulsar binary J0737–3039

A recent multibeam pulsar survey of the outer Galactic plane at Parkes has discovered the first-known double-pulsar binary, a very compact double neutron star system in which both stars are observable as radio pulsars. In this review, we briefly describe the discovery and the studies which have been enabled by the unique properties of the system. These range from the most precise confirmation yet of the theory of general relativity, with the possibility of even more new tests and the measurement of second-order post-Newtonian effects, to studies of the magnetospheres and emission properties of the two pulsars. The discovery also results in a significant increase in the expected rate of occurrence of the mergers of double neutron star systems, and hence the rate of detection of such events by the new ground-based gravitational wave detectors.     

八丝热线探针制作及其应用

介绍了八丝热线探针的制作工艺,有效地消除了各热丝探头之间的电信号干扰和动力学干扰。实验中使用该探针检测到了湍流边界层内的大尺度旋涡,并测量了它们的强度和尺度。与此同时还获得了速度、湍流强度和功率谱等流场参数,结果与现有典型数据一致。说明本文所述的多丝热线探针具有很强的实用性。