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Black phosphorene is a kind of two-dimensional layered material with special structure and excellent physical properties. It is a kind of middle temperature thermoelectric material with application prospect. In this paper, the advantages and disadvantages of the two methods are discussed by summarizing and comparing the experimental research and simulation calculation methods of the thermoelectric properties of black phosphorene. The characteristics and unique anisotropy of the thermoelectric transport performance of black phosphorene were studied, and the influence of different regulation methods on the thermoelectric transport performance of black phosphorene was analyzed. This paper can provide reference for the research methods of related thermoelectric materials. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Liaoning Technical University (Natural Science Edition) / Liaoning Gongcheng Jishu Daxue Xuebao (Ziran Kexue Ban) is the property of Journal of Liaoning Technical University (Natural Science) Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to the layer characteristics and anisotropic mechanical properties of 3D printed concrete, there is still lacking effective numerical simulation method for force analysis of 3D printed concrete. In this paper, the linear elastic constitutive parameters of 3D printed concrete anisotropic equivalent elements are deduced, based on the deformation conditions and mechanical equilibrium conditions, and based on the shear stress reciprocity theorem, the layer stress calculation method of 3D printed concrete is given. A 100 mm×100 mm×100 mm 3D printed concrete cubic block is taken as an example. The ANSYS finite element software is carried out to simulate the force performance of 3D printed concrete. The results show that the number of elements obtained by the equivalent element method is reduced by 64 times, the overall error of the displacement results can be controlled within 1%, and the calculation efficiency is increased by more than 430 times. Through the research in this paper, the finite element simulation analysis of anisotropic 3D printed concrete with layer characteristics is realized, which can greatly improve the calculation efficiency under the premise of ensuring the calculation accuracy. [ABSTRACT FROM AUTHOR]

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Copyright of Foundry Technology (1000-8365) is the property of Foundry Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Drilling Fluid & Completion Fluid is the property of Drilling Fluid & Completion Fluid Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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In this paper, on the basis of density functional theory（DFT）, the elastic properties of cubic Ia...phase of magnesium phosphide（Mg3P2） were studied theoretically by first principles calculation and elastic theory. The independent elastic constants and elastic compliance constants of Mg3P2 in cubic Ia... phase are obtained by using two methods of calculating elastic constants, namely energy-strain（E-S） and stress-strain（S-S）. By comparing the elastic constants of single crystals calculated by the two methods, it is shown that the S-S method is in better agreement with the literature values of previous researchers. Therefore, the polycrystalline elastic modulus of cubic Ia...Mg3P2, such as elastic modulus E and shear modulus G, are obtained on the basis of the S-S method, as well as a series of physical parameters such as B/G, Poisson’s ratio and anisotropy factor. It is shown that cubic Ia...Mg3P2satisfies the mechanical stability condition of cubic phase, which proves that it is a structure in mechanical stability state. At the same time, the calculated physical parameters show that cubic Ia...Mg3P2 has the characteristics of toughness. In order to further analyze and verify the characteristics of the materials, we calculated the Vickers hardness. By analyzing the calculated anisotropy factors and the 3D surface images of elastic modulus, linear compression coefficient and shear modulus, which represents the dependence of the elastic properties on the crystal direction, both show that the degree of anisotropy of cubic Ia...Mg3P2 is weak, and the latter is more intuitive. In addition, Debye temperature of Ia...Mg3P2 and sound velocity in different directions are also calculated in this paper. The results show that the interatomic force of Ia...Mg3P2 is weak, and the longitudinal wave propagates the fastest along the direction [111] and the shear wave propagates the slowest along the direction [110] under the condition of zero temperature and zero pressure. [ABSTRACT FROM AUTHOR]

Copyright of Reviews of Geophysics & Planetary Physics is the property of Editorial Office of Reviews of Geophysics & Planetary Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Journal of Synthetic Crystals is the property of Journal of Synthetic Crystals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of CT Theory & Applications is the property of Editorial Department of CT Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the increasing application of nanocellulose materials, it is found that some nanocellulose composites can improve its overall performance and have low cost and wide sources. Nanocellulose materials such as subnanometer cellulose crystal (CNC), microcrystalline cellulose (MC'C), nanocellulose (NFC), bacterial nanocellulose (BNC) and other materials are prepared by different methods. With the help of mechanical stretching, spinning, electric field, magnetic field and other methods, it is used to prepare directional alignment with high orientation and high performance. Nanocellulose materials with high strength and stiffness are used in textile industry, medical industry, optical devices and other fields. Tn this paper, these methods and materials are briefly discussed and the application characteristics of materials and methods are summarized. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Computational Mechanics / Jisuan Lixue Xuebao is the property of Chinese Journal of Computational Mechanics Editorial Office, Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Computer-Aided Design & Computer Graphics / Jisuanji Fuzhu Sheji Yu Tuxingxue Xuebao is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of China University of Petroleum is the property of China University of Petroleum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The existing methods of uniform light and color for remote sensing images are based on the transformation of global and semi-global statistical parameters. They lack the content drive guided by local feature information and cannot take into account the difference in each image content, resulting in poor color uniformity, loss of contrast, and obvious residual color difference. By analyzing the essential causes of color difference between images, the observation values of homonymous features in images under different lighting environments were taken as the observation conditions, and local space constraints and correction regularization constraints were supplemented to study and construct an anisotropic optimization method for image sets with overlapping areas. The method used convex optimization theory to solve the correction amounts at the homonymous feature points, and then used the correction amounts as the anchor points to radiate the space to the whole image and obtained the optimal uniform light and color effects through linear weighted correction. The results have showed that, compared with the traditional algorithm, the proposed algorithm for light and color equalization of remote sensing images based on anisotropy was more complete in theory, without assumptions and preconditions, have achieved better results, and with less chromatic aberration in the local range of the overlapping area images. It can be seen that the uniform light and color algorithm proposed in this paper is effective and progressiveness, and this research has reference value for the research of anisotropic uniform light and color algorithms. [ABSTRACT FROM AUTHOR]

In this paper, the effect of the process parameters of reciprocating diamond wire saw on the surface quality of the (001) plane β-Ga2 O3 single crystal was investigated. According to the theory of the indentation fracture mechanics, the abrasive behavior and material removal mechanism in the process of cutting β-Ga2 O3 single crystal with diamond wire saw were investigated. The influence of the cutting direction on the surface quality of the (001) plane β-Ga2 O3 single crystal was analyzed from the aspect of anisotropy, SEM and SJ-210 roughness measuring instrument were used to explore the effect of process parameters on the quality of wafer surface after diamond wire saw. The experimental results show that the depth of subsurface damage layer can be reduced and the surface quality of the wafer can be effectively improved by increasing the wire speed or decreasing the feed rate. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phonon polartions are half-light and half-mater quasiparticles form by light-phonon interactions in polar crystals, which enables break through the limitation of diffraction limit, therefore, it is significant for superresolution imaging, photolithography, surface spectra enhancement and so on. However, the existing phonon polaritons are isotropic, phonon polaritons with anisotropic propagation and even topological dispersion transformation are crucial for subwavelength light manipulations. In this paper, we investigate anisotropic phonon polaritons in MoO3, disparate polaritons dispersion can be found in the Reststrahlen bands of MoO3.By means of fabricating twisted double layers of MoO3, phonon polariton dispersions will experience topological transformation from hyperbolic type to flat band and finally oblate square through tuning the twisting angles. Our studies are important for phonon polariton controlling and designing applications at sub-diffraction scales. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Solving the problem of ambiguity of text words is important for text representation, and it can accurately define the semantic characteristics of words in a specific context. Aiming at the polysemy and contextual characteristics of words, this paper proposed a semantic disambiguation model of SCDVAB. The main innovations are: Based on the partition average technology, it can convert scene corpus into document embedding, and introduce anisotropy to improve the sparse composite document vector（SCDV） algorithm of soft clustering to improve the contextual representation ability of BERT; and then it can improve the ability of text semantic disambiguation by embedding the BERT words after adjusting the anisotropy as a static word vector. Through many experiments, SCDVAB model is significantly better than the traditional text disambiguation algorithm. SCDVAB model can effectively improve the comprehensive performance of text semantic disambiguation. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Formalin solution has been widely used to solidify the organization of articular cartilage and prevent tissue decomposition in long-time measurement. However, it was rarely investigated that the structural anisotropy changes of collagen fiber (fixation) of articular cartilage when it was immersed in formalin. In this paper, Fourier transform infrared spectroscopic imaging with polarization technique was used to investigate the anisotropic structure change of collagen fiber of articular cartilage fixed in formalin through the absorbance change of Amide I and Amide II with immersing time and polarization direction. The degree of anisotropy of collagen fiber in cartilage was characterized with fitting related coefficient of absorbance. The anisotropy of Amide I and Amide II became stronger with immersing extension of articular cartilage in formalin, and the amide I showed more remarkable anisotropy. It was concluded that the formalin solution induced new crosslinks of collagen, which gradually strengthened the collagen fiber anisotropy and was helpful for the structural analysis of the articular cartilage. The study will be significant for the preparation, preservation and anisotropy research of cartilage specimen.

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Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of China University of Petroleum is the property of China University of Petroleum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Image & Graphics is the property of Editorial Office of Journal of Image & Graphics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Image & Graphics is the property of Editorial Office of Journal of Image & Graphics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming to solve the problem of abnormal missing holes occurred in 3D reconstruction mesh models frequently, this paper proposed a novel method that hole-defect identification automatically and detail-preserving surface repair around the hole. Firstly, in order to determine whether the hole was a real defective hole, it detected the context irregularity and contour irregularity of the missing region. After that, it detected and matched the feature lines around the hole, which were to form the fundamental surface of the hole area, and then it introduced unconstrained triangulation for basal surface. Finally, it made use of the anisotropy of mesh to refine and adjust morphologically to improve the topological and geometric properties of the mesh. The experimental results show that the proposed method can identify the defective hole and restore the hole area' s detail features of triangular mesh models effectively. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Computational Mechanics / Jisuan Lixue Xuebao is the property of Chinese Journal of Computational Mechanics Editorial Office, Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The anisotropy of fracture properties at different bedding orientations of lignite plays an important role in controlling the formation of fracture network of reservoir racturing. The static fracture behavior of the lignite semi-circular bending specimens of the 6 coal group in the Shengli coalfield, Inner Mongolia, is studied. The results show that: ① Bedding When the angle θ is 90°, 60°, 45°, 30° and divider, the mode I fracture toughness KIC of lignite of Shengli coalfield is 0.045, 0.058, 0.073, 0.084 and 0.096 MPa·m0.5, respectively. on the whole, the fracture toughness of the sample with the notch-cut layered surface is much higher than that of the notch-parallel bedding-surface sample, and for the notch-parallel bedding-surface sample, the There is an increasing trend with decreasing fracture toughness, and the fracture properties of lignite in the study area have strong anisotropic characteristics; ② The displacement-load curves shows that the fracture process of the five lignite semi-circular bending samples under three-point bending loading includes: the compaction stage of pores and cracks, the linear elastic compression deformation energy storage stage, the critical fracture failure stage, and the load unloading stage after fracture. The large stage, and the rapid load unloading of the above samples in the later stage of fracture indicates that the material fracture forms are brittle fractures, the coal has a large fracture rate, and the reservoir is suitable for large-scale volume fracturing; ③ The fracture energy Γ of five kinds of lignite semi-circular bending samples with the bedding angle θ is 90°, 60°, 45°, 30° and dividing during three-point bending loading process is 64.38, 80.49, 112.50, 146.66, and 355.00 J/m2, respectively. The fracture energy of the sample with the notch-cut layered surface in the whole process is much larger than that of the lignite sample of the incision-parallel bedding plane. Under the same conditions, the energy consumption of fracturing along the bedding direction of the split lignite is high, and the expansion scale of the fracturing fracture is limited; ④ Under three-point bending loading, the fractures of the lignite semi-circular bending specimens in the study area mainly include tensile fractures and shear fractures. The fracture path of the lignite specimens is controlled by the spatial relations between the external loading direction and the orientation of the coal bedding plane When the bedding angle θ is between 45° and 60°, the degree of tortuosity of the fracture of the sample is the highest, and the fracture network is most likely to be formed in the coal reservoir fracturing; ⑤ Based on the fracture mechanics anisotropy of lignite, this paper believes that horizontal wells + staged fracturing in lignite reservoirs can greatly improve the complexity of fracturing fractures. In addition, considering the inertia of particles, the horizontal wells with the borehole direction parallel to the maximum horizontal principal stress can carry proppant smoothly and avoid plugging, and the fracture filling effect is better. The above understanding is expected to provide a certain scientific reference for the reservoir volume fracturing stimulation and fracturing network construction in the study area.

In the process of underground excavation, the surrounding rock is in a very complex stress environment, especially under the influence of its anisotropy, the occurrence of dynamic disaster is hidden. In this paper, the loading and unloading tests of sandstone in different principal stress directions were carried out by using the true triaxial unloading disturbed rock test system. The mechanical properties and failure characteristics of true triaxial under different principal stresses were studied, the energy evolution mechanism in other directions induced by loading and unloading of different principal stresses was analyzed. Results showed that under the influence of rock mass secondary stress anisotropy, during the cyclic loading and unloading process of the first principal stress, the strain in other directions shows opposite deformation. The volumetric strain compresses first and then expands, and the final volumetric strain shows a macroscopic phenomenon of expansion. When the third principal stress of high confining pressure rock mass is unloaded, the first principal stress produces a compression deformation, while the second and third principal stresses produce an expansion deformation. The deformation of the second principal stress is less than that of the third principal stress, and the deformation in unloading direction changes from linear elastic state to elastic-plastic nonlinear state. The accumulated energy of rock mass is a great difference between the first principal stress unloading and the third principal stress unloading. The energy variation characteristics of unloading in the dominant direction determine the energy accumulation and release law in the other two induced directions. The limit stored energy of the third principal stress unloading rock decreases, and the second principal stress accelerates the rock failure with the increase of the first principal stress, which verifies that the rock is easier to be destroyed by unloading than by loading. The higher the unloading rate of the third principal stress, the higher the energy released and the lower the dissipated energy, and the lower the energy density and total accumulated energy density in the unloading direction of rock mass. The main cause of dynamic accidents is the accumulation and release of energy in rock mass. The secondary anisotropy of rock mass has a great influence on the ultimate stored energy of rock mass. The study on the influence characteristics of three-dimensional loading and unloading secondary stress on the ultimate stored energy of rock mass provides a reference for preventing rock burst.

The ray path of Pn waves is concentrated in the limited depth range of the uppermost mantle, which has unique advantages in ray transverse coverage density. Therefore, the Pn phase is the dominant phase for studying the velocity and anisotropic structure of the uppermost mantle. The lateral variation of Pn wave velocity reflects the temperature and composition difference of the uppermost mantle, and Pn anisotropy can reflect the movement of the mantle material and deformation characteristics. The high accuracy of Pn wave velocity and anisotropy structure in the uppermost mantle can provide key information about the lithospheric structure, plate movement, and deep thermal material migration process. With development and improvement, Pn tomography has become a mature technology to study the structure of the uppermost mantle and has been applied to obtain structural information such as crustal thickness, upper mantle velocity, and anisotropy on a global scale. This method characterizes the lateral heterogeneity of the global upper mantle structure and provides further understanding of the Earth's internal structure and plate subduction, continental collision deformation, volcanic activities, and other dynamic processes. With increasing global seismic stations and observation data, a large amount of high-quality Pn data provide favorable conditions for the study of the structure of the uppermost mantle. This paper reviews the development of the Pn tomography method and its applications in the world.

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The aim of this paper is to quantitatively evaluate the effect of mining-induced damage on the stability of joint rock slope.By means of site survey and fuzzy C-mean optimization algorithm,the random distribution parameters of the dip direction,dip angle,trace length and density of two dominant joint sets in footwall migmatite slope of Dagushan iron mine were obtained.Considering the relationships among Hoek-Brown parameters (m,s) and Geological Strength Index (GSI) and disturbance coefficient (D),the random distribution parameters of jointed rock mass strength were obtained by Monte Carlo method.After establishing the relationship between the damage and disturbance parameters of jointed rock mass,the Kawarnoto damage tensor was employed to carry out the numerical simulation of the mining-induced damage.Then the random distribution parameters (D) and rock mass strength with spatial-temporal distribution characteristics and anisotropy were obtained according to the Rosenblueth principle.The slope reliability index was calculated based on the strength parameters of rock mass with spatial-temporal distribution characteristics.The result shows that while the elevation of the stope bottom decreases from -87 m to -450 m,the reliability index of slip circle from the top of slope to -87 m level decreases 7.7% relatively.This is because that the increase of mining depth aggravates the damage in joined rock mass and weakens its strength.The potential slip surface gradually move to the slope surface,which has a greater correlation with the damage in rock masses near the slope. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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To resolve the difficult problem of soft tissue segmentation of MRI images of the segmentation of the multi target region of interest in the MRI images with complex targets and fuzzy boundary, this paper proposed a novel MRI image segmentation method, based on anisotropic diffusion and spatial fuzzy C-means clustering (SFCM). It preprocessed the images using the nonlinear and anisotropic diffusion, resolving the problem of weakening the image details while removing the noise. It designed space function combining with the neighborhood space, improving traditional FCM objective function. It used the spatial information of the image to achieve the accurate classification of every object in image was an effective solution to the isolated area correctly classified. After that, it obtained complete and continuous segmented regions. Finally, it utilized the fitting curve of histogram to initialize the classification number and the initial cluster centers, accelerating the algorithm iterative to the optimal solution, and also reducing the run time. The experiments show that the possibility of find a best solution is improved by introducing the method of MRI image segmentation method based on anisotropic diffusion and spatial FCM, so as to the processing of MRI images segmentation which has overlapped grayscale, discontinuous objects and fuzzy boundary. [ABSTRACT FROM AUTHOR]