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EXPERIMENTS ON IMPACT-BASED FORECASTING AND RISKBASED WARNING OF TYPHOON IN CHINA

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Tropical Cyclone Research and Review 2018年第1期7卷 31-36页

作者： LI WEI JIAYING LI XUAN YANG National Meteorological Centre of China Meteorological Administration

Typhoon is one of the disastrous weather systems that usually occur in summer and autumn in China’s *** and rainstorms brought by typhoon can directly cause serious loss in economy and also induce storm surge,flash flood,mud-rock flow,landslide and other secondary *** article studies the impact of collapsing force of typhoon gale and the risk-based warning of typhoon *** calculating the accumulated wind pressure and the designed wind load of bearing walls of low-rise building in coastal region,we define the damaged building *** addition,four steps for the risk-based warning or impact forecasting for small and medium-sized river basins,flash flood,mud flows and landslides caused by Typhoon rainstorm are introduced,which include understanding vulnerability of disaster carriers,developing risk thresholds of disasters,improving the accuracy of QPE/QPF and the risk assessment skill.

关键词： collapsing force of typhoon wind pressure damaged building index torrential rainfall risk-based warning

A Mathematical Interpretation of Hawking’s Black Hole Theory by Ricci Flow

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Journal of Applied Mathematics and Physics 2017年第2期5卷 321-328页

作者： Qiaofang Xing Xiang Gao Institute of Science Information Engineering University Zhengzhou China School of Mathematical Sciences Ocean University of China Qingdao China

In this paper, using Perelman’s no local collapsing theorem and the geometric interpretation of Hamilton’s Harnack expressions along the Ricci flow introduced by R. Hamilton, we present a mathematical interpretation... 详细信息

关键词： Black Hole Ricci Flow No Local collapsing Theorem Uncertainty Principle Harnack Expression

Kruskal Coordinates and Mass of Schwarzschild Black Holes: No Finite Mass Black Hole at All

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International Journal of Astronomy and Astrophysics 2012年第4期2卷 236-248页

作者： Abhas Mitra Theoretical Astrophysics Section Bhabha Atomic Research Centre India

When one presumes that the gravitational mass of a neutral massenpunkt is finite, the Schwarzschild coordinates appear to fail to describe the region within the event horizon (EH), of a Schwarzschild Black Hole (SBH). Accordingly, the Kruskal coordinates were invented to map the entire spacetime associated with the SBH. But it turns out that at the EH (Mitra, IJAA, 2012), and the radial timelike geodesic of a point particle would become null. Physically this would mean that, the EH is the true singularity, i.e., M = 0, and this zero mass BH could only be a limiting static solution which must never be exactly realized. However, since in certain cases , here we evaluate this derivative in such cases, and find that, for self-consistency, one again must have at the EH. This entire result gets clarified by noting that the integration constant appearing in the vacuum Schwarzschild solution (and not for a finite object like the Sun or a planet), is zero (Mitra, J. Math. Phys., 2009). Thus though the Schwarzschild solution for a point mass is formally correct even for a massenpunkt, such a point mass or a BH cannot be formed by physical gravitational collapse. Instead, physical gravitational collapse may result in finite hot quasistatic objects asymptotically approaching this ideal mathematical limit (Mitra & Glendenning, MNRAS Lett. 2010). Indeed “the discussion of physical behavior of black holes, classical or quantum, is only of academic interest” (Narlikar & Padmanbhan, Found. Phys. 1989).

关键词： Kruskal Coordinates Black Hole Black Hole Alternatives Eternally collapsing Object

Two Physical Constraints upon the Motions of Celestial Bodies

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Journal of Modern Physics 2019年第3期10卷 344-361页

作者： Xiaobai Ai Shanghai Institute of Applied Physics The Chinese Academy of Sciences Shanghai China

There exist two physical constraints upon the motions of celestial systems. Constraint 1 reveals during collapse or explosion motion of celestial bodies that there would be an unattainability upper limit for their compact intensity (total mass M/scale size R), which arises from the Lorentz invariance of the time-like metric in local four-dimensional continuum in Einstein’s theory of special relativity. Constraint 2 points that the average mass density of nucleon would be an unsurpassed upper limit for bulk normal matter in nature, which arises from Heisenberg’s uncertainty principle. A very important effect is that the combination of these two physical constraints would prevent the formation of black holes.

关键词： General Theory of Relativity Gravitation collapsing Schwarzschild Metric Schwarzschild Singularity Centre Singularity Black Hole Compact Intensity Heisenberg’s Uncertainty Principle

Growing Sandpile Problem with Local and Non-Local Boundaries Conditions

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Journal of Applied Mathematics and Physics 2021年第10期9卷 2414-2429页

作者： Urbain Traoré Laboratoire de Mathématiques et d’Informatique (LAMI) UFR Sciences Exactes et Appliquées Université Ouaga I Pr Joseph

In this paper, we study a class of Prigozhin equation for growing sandpile problem subject to local and a non-local boundary condition. The problem is a generalized model for a growing sandpile problem with Neumann boundary condition (see [1]). By the semi-group theory, we prove the existence and uniqueness of the solution for the model and thanks to a duality method we do the numerical analysis of the problem. We finish our work by doing numerical simulations to validate our theoretical results.

关键词： Sandpile collapsing Avalanche Nonlinear Semi-Group Nonlocal Boundary Conditions Euler Discretization in Time Time Dependent Gradient Constraints

Several Typical Geomechanical Models of Deformation Fracture of Mountain in High Earthquake Intensity Area

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地学前缘 2009年第S1期16卷 72-72页

作者： Xiangning Xu,Lansheng Wang 1.Chengdu University of Technology,Chengdu,610059,China. 2.Chengdu Center of Hydrogeology and Engineering Geology of Sichuan Provincial GMR Bureau,Chengdu,610081,China

The deformation fracture and stability of mountain under the earthquake action is an important issue that arouses concern of researchers in the field of engineering *** authors,from 2000 to 2006, selected the 1933 earthquake in Diexi zone as a typical study site to carry out the genetic mechanism research of mountain deformation-fracture caused by earthquake; in order to have comparability,the breadth

关键词： high earthquake intensity area deformation fracture mechanism Geo-mechanical model bedded landslide model collapsing model landslide model