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This article presents a robust hand-gesture recognition method via multidimensional feature representation and learning specifically designed for commercial frequency-modulated continuous wave (FMCW) multi-input multi-output (MIMO) millimeter-wave radar. First, the optimal configuration of the radar system parameters for the hand-gesture recognition scenario is investigated and a standard procedure to determine the system configuration is given. Then a moving scattering center model is proposed to represent the 3-D point cloud in the range–Doppler (RD)-angular multidimensional feature space. A scattering point detection and tracking algorithm is presented based on a set of motion constraints in terms of position, velocity, and acceleration. It is derived from the space-time continuity of a nonrigid target. Finally, a lightweight multichannel convolutional neural network (CNN) is designed to learn and classify multidimensional gesture features including radial RD and tangential azimuth–elevation. Extensive experiments are carried out with the developed system and a large data set is obtained to train and test the classifier. The results show that the proposed gesture recognition method can effectively distinguish gestures that are easily confused in the RD domain and achieve robust performances under various conditions.

Strongly swirling flow is widely encountered in engineering applications. However, accurate prediction of the flow is still challenging for turbulence modeling. The present study reports the assess...

In the early 20th century, the interpretation of the poem "Wei Jiao Zhongqing Qi Zuo" or "For Jiao Zhongqing's Wife" was mainly based on the social context at the time, which, however, might deviate from the original purpose of the female writing in the work. The poem once witnessed several modifications from the late Eastern Han Dynasty to the Southern Dynasties when the development of traditional Confucian code of ethics took off. The rewritings of female writing in literature works were to adapt to the male-dominated moral codes and discourse system at that time. Based on that, the female writing in the poem was processed, and evidence would be that from the perspective of content, the persona of Liu (Jiao's wife) portrayed in the poem changed greatly while characters like Jiao Zhongqing and Mother Jiao (Jiao's mother) were enriched. In addition, some new plots and characters were created for example, Brother Liu (Liu's brother) and Mother Liu (Liu's mother). In regard to the narrative strategy, the processed version intentionally emphasized the absence of "father" and "unrighteousness" of the brother to serve to the plot of suicide for love of Liu. This type of narrative poems conveying both criticism and praise was a tool used to complete and consolidate the ethical discourse and restrain women's influence on men, and it also echoed the traditional view of women passed from the Qin and Han Dynasties which for sure further confined women's free choice.

The principal component analysis (PCA) is used to analyze the high dimensional chemistry data of laminar premixed/stratified flames under strain effects. The first few principal components (PCs), which have larger contribution ratios, are chosen as the tabulated scalars to build the look-up chemistry table. Prior tests show that the strained premixed flame structure can be well reconstructed. To highlight the physical meanings of the tabulated scalars in the stratified flames, a modified PCA method is developed, where the mixture fraction is used to replace one of the PCs with the highest correlation coefficient with a mixture fraction. The other two tabulated scalars are then modified with the Schmidt orthogonalization. The modified tabulated scalars not only have clear physical meanings, but also contain passive scalars. The PCA method has good commonality, and can be extended for building the thermo-chemistry table including strain rate effects when different fuels are used.

In x Ga1− x Sb is a ternary alloy with tunable properties. The wavelength of In x Ga1− x Sb can be varied in the range of 1.7– 6.8 μm, which is in the infrared (IR) region and makes that In x Ga1− x Sb can be used as a substrate for IR detector and thermophotovoltaic (TPV). The phase diagram reveals that there is a large temperature gap between liquidus and solidus lines, which leads to constitutional supercooling and the formation of crystal defects during the solidification process of InGaSb crystal. Moreover, convection caused by gravity will increase the inhomogeneity of transport in the liquid region near the crystal growth interface, which makes it quite difficult to grow In x Ga1− x Sb crystal. The convection will be restrained in microgravity environment, and thus, it is very beneficial for crystal growth. This article introduces the effect of microgravity on the growth of In x Ga1− x Sb crystal and the results of the space growth experiment of In x Ga1− x Sb ternary crystal with a high concentration of In in SJ10 recoverable scientific experimental satellite.