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Guo R.,Taiyuan University of Technology | Zhao H.-H.,Taiyuan University of Technology | Wang Y.,Shanxi Coal Mining Administrators College
Nonlinear Dynamics

Under investigation in this paper is a generalized coupled nonlinear Schrödinger system with higher-order terms, which describes the propagation properties of ultrashort solitons in two ultrashort optical fields. Based on the 3 (Formula presented.) 3 lax pair, the N-fold Darboux transformation (DT) has been constructed. Several kinds of solitons, breathers, and rogue wave solutions are generated on the vanishing and nonvanishing backgrounds by virtue of the DT. Figures are plotted to reveal the dynamic features of those solutions: (1) elastic interactions between two solitons; (2) mutual attractions and repulsions of bound solitons; (3) propagation properties of Ma-breathers, Akhmediev breathers, two-breathers, and rogue waves. The results show that the rogue waves can result from two different ways: the limit process of Ma-breathers and Akhmediev breathers. © 2015, Springer Science+Business Media Dordrecht. Source

Wu M.-Q.,CAS Institute of Remote Sensing Applications | Wang J.,Hangzhou Normal University | Niu Z.,CAS Institute of Remote Sensing Applications | Zhao Y.-Q.,Shanxi Coal Mining Administrators College | Wang C.-Y.,CAS Institute of Remote Sensing Applications
Hongwai Yu Haomibo Xuebao/Journal of Infrared and Millimeter Waves

Spatial and temporal fusion of remote sensing data is a technology that can generate dense time series and high spatial resolution data whose spatial resolution is similar with high spatial resolution date, and temporal resolution is the same as the one with high temporal resolution data. This paper presented a new spatial and temporal data fusion model (STDFM) for blending Landsat and MODIS surface reflectance. Temporal change information was detected from sequence coarser resolution surface images, and new high resolution reflectance was predicted from former high resolution reflectance. This algorithm was tested in red and near-infrared MODIS and Landsat ETM+ images, and over a study area in Jiangning country, Nanjing, Jiangsu, China. Results showed that STDFM was able to produce images very similar with actual observed images. The correlation coefficient r between synthetic imageries and actual observations was 0.939. The correlation coefficient r between NDVI calculated by synthetic imageries and actual observations was 0.938. Source

Yang B.,Hebei University of Engineering | Yang B.,Key Laboratory of Resource Survey and Research of Hebei Province | Li H.,Hebei University of Engineering | Sun L.,Hebei University of Engineering | And 3 more authors.
International Journal of Mining and Mineral Engineering

Based on the deformation and destruction characteristics of deep roadways, we developed a 'double shell' support theory, which applied both deep and shallow grouting along with bolts (cable) as the support shells. Through investigation of the support conditions of deep roadways in north China and referring to the Standard for engineering classification of rock masses, we summarised an optimisation table of 'double shell' support schemes in deep roadways. We also determined the parameters on the basis of the 'double shell' support theory, the indices of the rock grade and the mining depth of roadways. Considering the specific engineering condition of the water pump chamber of Xiandewang Coal Mine, we determined the grade of surrounding rock and established the 'single shell' (bolt + steel-mesh + cable + shotcreting + middle-deep grouting) support scheme by referring to the optimisation table. These efforts showed a good supporting effect and validated the applicability of the table. © 2015 Inderscience Enterprises Ltd. Source

Nie H.,Taiyuan University of Technology | Nie H.,Shanxi Coal Mining Administrators College | Liang W.,Taiyuan University of Technology | Chi C.,Taiyuan University of Technology | And 4 more authors.

Three-layered 5052Al/AZ31Mg/5052Al (5052/AZ31/5052) clad sheets were fabricated by four-pass rolling and annealed under different conditions. Under the optimal annealing condition, homogeneous and equiaxial grains with an average AZ31 grain size of 5.24 µm were obtained and the maximum values of ultimate tensile strength and elongation of the clad sheet reached 230 MPa and 18%, respectively. Electron backscatter diffraction analysis showed that the AZ31 layer had a typical rolling texture with its c-axis parallel to the normal direction. The fraction of low-angle grain boundaries in the 5052 layer was nearly four times more than that in the AZ31 layer because of different deformation extent and recrystallization driving forces. The textures of Al3Mg2 and Mg17Al12 were similar to that of 5052 because of the deformation coordination during the rolling and recrystallization process. The orientation relationship between Mg17Al12 and AZ31 seemed to be (110) Mg17Al12//(10−11) AZ31. © 2015 The Minerals, Metals & Materials Society Source

Hu C.X.,China University of Mining and Technology | Hu C.X.,Shanxi Coal Mining Administrators College | Liu J.K.,China University of Mining and Technology | Li Q.,China University of Mining and Technology | Zhang Y.,China University of Mining and Technology
Applied Mechanics and Materials

The gob of small colliery has been one of the main factors threatening the safe production of coal mine. The repeated mining working face in a certain mine is the practical engineering background in this paper to study the influence of gob in small colliery on the mining of lower layer. By using the numerical simulation software FLAC3D, the stress distribution law and the change of displacement during lower layer mining were analysed. It can be concluded from the analysis of field measurement data that: there is stress relief under the gob of small colliery because the distribution of coal is irregular resulting from the random distribution of gobs in small colliery, while the residual coal causes the effect of stress concentration on the lower layer mining; relatively large displacement appears in the caving zone of the upper layer by the roof of working face and the support should be strengthened appropriately during mining; meanwhile, the gob of small colliery can cause the nonuniform distance of periodic weighting in the roof, and segmented pressure behavior can be observed during the periodic weighting of the working face. Research results could provide some guidance to the safe and efficient production in repeated mining working face in the mining with similar conditions. © (2014) Trans Tech Publications, Switzerland. Source

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