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Gait recognition is a powerful tool for long-distance identification. However, gaits are influenced by walking environments and appearance changes. Therefore, the gait recognition rate declines sharply when the viewing angle changes. In this work, we propose a novel cross-view gait recognition method with two-way similarity learning. Focusing on the relationships between gait elements in three-dimensional space and the wholeness of human body movements, we design a three-dimensional gait constraint model that is robust to view changes based on joint motion constraint relationships. Different from the classic three-dimensional model, the proposed model characterizes motion constraints and action constraints between joints based on time and space dimensions. Next, we propose an end-to-end two-way gait network using long short-term memory and residual network 50 to extract the temporal and spatial difference features, respectively, of model pairs. The two types of difference features are merged at a high level in the network, and similarity values are obtained through the softmax layer. Our method is evaluated based on the challenging CASIA-B data set in terms of cross-view gait recognition. The experimental results show that the method achieves a higher recognition rate than the previously developed model-based methods. The recognition rate reaches 72.8%, and the viewing angle changes from 36° to 144° for normal walking. Finally, the new method also performs better in cases with large cross-view angles, illustrating that our model is robust to viewing angle changes and that the proposed network offers considerable potential in practical application scenarios.

In this paper, we investigate free thickness-shear and thickness-twist vibrations of a finite crystal resonator of AT-cut quartz carrying a thin mass layer at the central portion of its top surface operating as a quartz crystal microbalance. The equations of anisotropic elasticity are used with the omission of the small elastic constant c56. An analytical solution is obtained using Fourier series from which the resonant frequencies, mode shapes and vibration confinement by the mass layer are calculated and examined.

During Jan 11-Feb 2, 2008, affected by cold air, a rare cryogenic sleet and snow weather process occurred in the southern China. To cope with this extreme weather condition, and to secure the expressway safety, for the first time some expressways used snowmelt agent in large areas. In order to make quantitative impact assessment for the snowmelt agent usage on roadside ecological environment under these extreme sleet and snow condition, field sampling surveys were conducted on the North Guangdong section and the Hunan Leiyi section of Beijing-Hong Kong-Macao Expressway, where the most snowmelt agent used on, in March 2008. The results showed that the snowmelt agents were dominated by salts, of which the main components are sodium chloride (NaCl) and sodium sulfate (NaSO4). After deicing, the concentrations of chloride, sulfate and sodium ions in water sampling from drainage edge ditches were (19.89?19.11) mgL?1, (45.73?29.67) mgL?1 and (14.41?16.65) mgL?1, respectively, which is 3.07 times, 2.08 times and 8.58 times that in the water outside the ditches; and these ion concentrations outside the ditches are slightly higher than that in the river nearby. The concentrations of these ions in the soil within 20 meter range of vertical distance from road exhibited a downward trend with the increase of distance from road. In the soil close to expressway (0.5-2.5 m), the main components of snowmelt agents accumulated within the depth of 10-20 cm; and soils a little bit far from expressway are not affected. In some road section, snow residue containing snowmelt agents were concentrated on roadside plant growth area, where the vegetation were killed by salt damage.

We report a high power continuous tunable blue light generation by frequency doubling of signal wave from a nanosecond 532-nm-pumped optical parametric oscillator (OPO) in LiB 3 O 5 (LBO). The nonlinear crystal BiB 3 O 6 (BiBO) is used for the second harmonic generation (SHG). Three BiBO crystals have been arranged for the walkoff compensation SHG. The large blue tuning range from 450 to 495 nm with average output powers around 1 W have been achieved. The maximum output power is up to 1.3 W at 470 nm.