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IRRIGATING warped SOILS——ANTHROPOGENIC SOIL IN ARID AND SEMI-ARID REGIONS OF CHINA

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干旱区资源与环境 1993年第Z1期7卷 235-237页

作者： Wang Jizhi Ningxia Institute of Agricultural Survey and Design

The irrigating warped soils occur in the old irrigation areas of arid and semi-arid re-gions of China, and distributed from Zhangjiakou of Hebei province, through InnerMongolia Autonomous Region, Ningxia Hui Autonomous Region, Gansu province,Qinhai Province, down to Xinjiang Autonomous Region, including the arid subalpine rivervalleys in the western part of Tibet.

关键词： China Arid and Semiarid Area Irrigating warped Soil Anthropogenic Soil

Alignment of Quasar Polarizations on Large Scales Explained by warped Cosmic Strings. PART II: The Second Order Contribution

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Journal of Modern Physics 2017年第2期8卷 163-180页

作者： Reinoud Jan Slagter Asfyon Bussum The Netherlands Amsterdam University Amsterdam The Netherlands

We find an azimuthal-angle dependent approximate wave like solution to second order on a warped five-dimensional manifold with a self-gravitating U(1) scalar gauge field (cosmic string) on the brane using the multiple-scale method. The spectrum of the several orders of approximation show maxima of the energy distribution dependent on the azimuthal-angle and the winding numbers n of the subsequent orders of scalar field. This breakup of the quantized flux quanta does not lead to instability of the asymptotic wavelike solution, due to the suppression of the n-dependency in the energy mo-mentum tensor components by the warp factor. This effect is triggered by the contribution of the five dimensional Weyl tensor on the brane. This con-tribution can be understood as dark energy and can trigger the self-acceleration of the universe without the need of a cosmological constant. There is a striking relation between the symmetry breaking of the Higgs field described by the winding number and the SO(2) breaking of the axially symmetric configuration into a discrete subgroup of rotations about 180°. The discrete sequence of non-axially symmetric deviations, cancelled by the emission of gravitational waves in order to restore the SO(2) symmetry, triggers the pressure Tzz for discrete values of the azimuthal-angle. There can be a possible relation between the recently discovered angle-preferences of polarization axes of quasars on large scales and our theoretical predicted angle-dependency and can be an evidence for the existence of cosmic strings. The discovery of the increase of polarization rate in smaller subgroups of the several large-quasar groups (LQGs), the red shift dependency and the relative orientation of the spin axes with respect to the major axes of their host LQGs, point at a fractional azimuthal structure, were also found in our cosmic string model. This peculiar discontinuous large scale structure, i.e., polarizations directions of multiples of, for example,

关键词： Quasar Polarization Cosmic Strings warped Brane World Models U(1) Scalar-Gauge Field Multiple-Scale Analysis

Osserman Conditions in Lightlike warped Product Geometry

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Journal of Applied Mathematics and Physics 2020年第4期8卷 585-596页

作者： Domitien Ndayirukiye Aboubacar Nibirantiza Gilbert Nibaruta Ménédore Karimumuryango Département des Sciences Naturelles Ecole Normale Supérieure Bujumbura Burundi Département des Mathématiques Institut de Pédagogie Appliquée Université du Burundi Bujumbura Burundi Institut des Statistiques Appliquées Université du Burundi Bujumbura Burundi

In this paper, we consider Osserman conditions on lightlike warped product (sub-)manifolds with respect to the Jacobi Operator. We define the Jacobi operator for lightlike warped product manifold and introduce a study of lightlike warped product Osserman manifolds. For the coisotropic case with totally degenerates first factor, we prove that this class consists of Einstein and locally Osserman lightlike warped product.

关键词： Lightlike warped Product Manifolds Curvature Tensor Pseudo-Jacobi Operator

N-Body Simulations of Gas-Free Disc Galaxies with SMBH Seed in Binary Systems

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International Journal of Astronomy and Astrophysics 2019年第3期9卷 173-190页

作者： R. Chan Coordenação de Astronomia e Astrofsica Observatório Nacional Rio de Janeiro RJ Brazil

We have shown the outcome of N-body simulations of the interactions of two disc galaxies without gas with the same mass. Both disc galaxies have halos of dark matter, central bulges and initial supermassive black hole (SMBH) seeds at their centers. The purpose of this work is to study the mass and dynamical evolution of the initial SMBH seed during a Hubble cosmological time. It is a complementation of our previous paper with different initial orbit conditions and by introducing the SMBH seed in the initial galaxy. The disc of the secondary galaxy has a coplanar or polar orientation in relation to the disc of the primary galaxy and their initial orbit are eccentric and prograde. The primary and secondary galaxies have mass and size of Milky Way with an initial SMBH seed. We have found that the merger of the primary and secondary discs can result in a final normal disc or a final warped disc. After the fusion of discs, the final one is thicker and larger than the initial disc. The tidal effects are very important, modifying the evolution of the SMBH in the primary and secondary galaxy differently. The mass of the SMBH of the primary galaxy has increased by a factor ranging from 52 to 64 times the initial seed mass, depending on the experiment. However, the mass of the SMBH of the secondary galaxy has increased by a factor ranging from 6 to 33 times the initial SMBH seed mass, depending also on the experiment. Most of the accreted particles have come from the bulge and from the halo, depleting their particles. This could explain why the observations show that the SMBH with masses of approximatelyis found in many bulgeless galaxies. Only a small number of the accreted particles has come from the disc. In some cases of final merging stage of the two galaxies, the final SMBH of the secondary galaxy was ejected out of the galaxy.

关键词： Simulation Disc Galaxy Supermassive Black Hole Binary Galaxies Merger warped Disc Galaxies

Modeling and Simulation of Adaptive Surface Tracked Vehicle Based on RecurDyn

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Open Journal of Modelling and Simulation 2013年第4期1卷 37-41页

作者： Wei Chen Jianming Zhan Hang Zhou Faculty of Mechanical Engineering and Mechanics Ningbo University Ningbo China

In order to improve the adaptability of the tracked vehicle in the road and strengthen the grip of the tracked vehicle, a track surface adaptive mechanism was provided. In theory, it has been proved practically. Meanwhile, RecurDyn, which is a multi-body kinematics software, was used to build a multi-body soft hybrid model, based on structure, elasticity, linear damping adaptive tracked vehicle;meanwhile the model was used to carry on the kinematics simulation. Through the comparison between simulated motion trail and that of traditional motion trail, this paper analyzed the deviation of the motion trail and also simulated the motion trail of the warped surface so as to test the adaptive ability of the mechanism. According to the results, the adaptive mechanism was equipped with great surface adaptability. It can also adapt to the complex warped surface, and enjoy a damping effect.

关键词： warped Surface Adaptation Tracked Vehicle Modeling and Simulation Adaptive Mechanism

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一种基于像素预测的图像可逆信息隐藏策略

计算机科学 2018年第2期45卷 189-196页

作者：项煜东吴桂兴中国科学技术大学软件学院合肥230051 中国科学技术大学苏州研究院江苏苏州215123

基于像素点预测的可逆信息隐藏(Reversible Data Hiding,RDH)是当今一种低失真、高容量的信息隐藏策略,特别是对于差值扩展和直方图平移算法而言,准确预测可以同时提高数据容量和减小图像失真。文中提出了一种基于像素预测差的直方图平... 详细信息

基于像素点预测的可逆信息隐藏(Reversible Data Hiding,RDH)是当今一种低失真、高容量的信息隐藏策略,特别是对于差值扩展和直方图平移算法而言,准确预测可以同时提高数据容量和减小图像失真。文中提出了一种基于像素预测差的直方图平移方案。首先,采用warped Distance算法来对像素值进行预测,并在此基础上利用图像的局部梯度来实现对像素值的更精确预测。综合上述两种策略,改进了现有的直方图平移算法,同时也给出了防止像素值在平移后溢出的建议。实验结果表明,相对于近年来的其他方案,该方案能够在保证图像质量的情况下有效提升数据嵌入量,并且通过调整数据嵌入层级,可以在具体使用该算法时针对图像质量和数据嵌入量进行权衡。这也进一步说明了利用图像的局部特性,特别是梯度与图像局部几何相似性,可以有效提升像素预测的精度,从而改善可逆信息隐藏的容量-失真性能。

关键词：可逆信息隐藏 warped Distance 局部梯度直方图平移

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基于局部梯度的WaDi图像插值

计算机技术与发展 2008年第6期18卷 76-78,82页

作者：申利平李开宇南京航空航天大学自动化学院江苏南京210016

线性插值算法容易产生细节模糊和边缘锯齿效应,为了较好地保持图像的边缘信息,改善图像的主观视觉效果,提出了一种改进的warped Distance (WaDi)图像插值方法。传统的WaDi算法是对空间线性插值的改进,但它仅仅利用了图像边缘的局部不对... 详细信息

线性插值算法容易产生细节模糊和边缘锯齿效应,为了较好地保持图像的边缘信息,改善图像的主观视觉效果,提出了一种改进的warped Distance (WaDi)图像插值方法。传统的WaDi算法是对空间线性插值的改进,但它仅仅利用了图像边缘的局部不对称特征来计算WaDi。除了局部不对称特征,局部梯度特征也是图像边缘的一种重要特征。文中采用将局部不对称特征和局部梯度特征相结合的方法来计算WaDi,可同时保持图像边缘的细节特征和非边缘的光滑性。实验结果表明,用该方法能获得高精度的插值图像。

关键词： warped Distance 局部梯度图像插值