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Imaging the spatial precession cone-shaped targets with narrowband radar is a new technical approach in mid-course recognition problem. However, most existing time-frequency methods still have some inevitable deficiencies for extracting micro-Doppler information in practical applications, which leads to blurring of the image. A new narrowband radar imaging algorithm for the precession cone-shaped targets is proposed. The instantaneous frequency of each scattering point is gained by using the improved Hilbert-Huang transform, then the positions of scattering points in the parameter domain are reconstructed. Numerical simulation and experiment results confirm the effectiveness and high precision of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Generallythe critical distance stress theory was applied for the fatigue limitestimation of general structures. In thismethod, it needs only two parameters, fatiguelimit of smooth specimen (σw0), and threshold stress intensityfactor range (∆Kth). In this paper we extended this method for theestimation of low cycle fatigue lifetoo. In this improvement wedefine the critical distance (rc’) on static strength conditions,which is calculated using ultimate tensile strength (σB) andfracture toughness (KIC), in addition to the critical distance onfatigue limit condition (rc). Then the critical distances of any lowcycle fatigue conditions can be calculated by interpolation of criticaldistance on fatigue limit (rc) with critical distance on staticstrength (rc’). By unifying these low cycle fatigue life estimationmethod with high cycle fatigue limit estimation method we can estimate the fullrange fatigue life easily. And to confirm the availabilityof this estimation method we perform the fatigue test for circlehole specimens, sharp V notch specimens andfretting fatigue specimens.

Novel carbon nanocages (CNCs) with various pore structures were produced at different temperatures and were subsequently deposited with Pt particles by a simple liquid reduction method with chloroplatinic acid as the Pt source and ethylene glycol as the reducing agent. The chloroplatinic acid was separately dropped and induced an excellent Pt particle distribution with small size. The electrocatalytical activity of the CNCs with Pt loadings was analyzed by cyclic voltammograms (CVs) in H2SO4and H2SO4/CH3OH solutions. Excellent electrocatalytical activity was presented compared with the commercial Pt/C catalyst. The specific surface area (SSA) and graphitic structure played an important role on the electrochemical activity. The Pt/CNCs catalyst with CNCs fabricated at 900 °C possesses not only good catalytic characteristics but also high economic yield.