Parallel Computing for LURR of Earthquake Prediction

The LURR theory is a new approach for earthquake prediction, which achieves a good result within China mainland and some regions in America, Japan, and Australia. However, the expansion of the prediction region leads to the refinement of its longitude and latitude and the increase of the time period. This requires more and more computations and volume of data reaching the order of GB, which will be very difficult for a single CPU. In this paper, adopting the technology of domain decomposition and parallelizing using MPI, we developed a new parallel tempospatial scanning program.

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Parallel finite-element method using domain decomposition and Parareal for transient motor starting analysis

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/compel-12-2018-0516 ◽

2019 ◽

Vol 38 (5) ◽

pp. 1507-1520 ◽

Cited By ~ 1

Author(s):

Yasuhito Takahashi ◽

Koji Fujiwara ◽

Takeshi Iwashita ◽

Hiroshi Nakashima

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Parallel Computing ◽

Domain Decomposition ◽

Parallel Computation ◽

Domain Decomposition Method ◽

Space Time ◽

Content Type ◽

Parallel Performance ◽

Element Method

Purpose This paper aims to propose a parallel-in-space-time finite-element method (FEM) for transient motor starting analyses. Although the domain decomposition method (DDM) is suitable for solving large-scale problems and the parallel-in-time (PinT) integration method such as Parareal and time domain parallel FEM (TDPFEM) is effective for problems with a large number of time steps, their parallel performances get saturated as the number of processes increases. To overcome the difficulty, the hybrid approach in which both the DDM and PinT integration methods are used is investigated in a highly parallel computing environment. Design/methodology/approach First, the parallel performances of the DDM, Parareal and TDPFEM were compared because the scalability of these methods in highly parallel computation has not been deeply discussed. Then, the combination of the DDM and Parareal was investigated as a parallel-in-space-time FEM. The effectiveness of the developed method was demonstrated in transient starting analyses of induction motors. Findings The combination of Parareal with the DDM can improve the parallel performance in the case where the parallel performance of the DDM, TDPFEM or Parareal is saturated in highly parallel computation. In the case where the number of unknowns is large and the number of available processes is limited, the use of DDM is the most effective from the standpoint of computational cost. Originality/value This paper newly develops the parallel-in-space-time FEM and demonstrates its effectiveness in nonlinear magnetoquasistatic field analyses of electric machines. This finding is significantly important because a new direction of parallel computing techniques and great potential for its further development are clarified.

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Simulation of Doppler Lidar Measurement Range and Data Availability

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech-d-15-0057.1 ◽

2016 ◽

Vol 33 (5) ◽

pp. 977-987 ◽

Cited By ~ 5

Author(s):

Matthieu Boquet ◽

Philippe Royer ◽

Jean-Pierre Cariou ◽

Mehdi Machta ◽

Matthieu Valla

Keyword(s):

Measurement Range ◽

Data Availability ◽

Lidar Measurement ◽

Doppler Lidar ◽

New Approach ◽

Density Distributions ◽

Time Period ◽

Atmospheric Observations ◽

Type Size ◽

Weather Stations

AbstractThe measurement range of a coherent wind Doppler lidar (CWDL) along a laser beam is the maximum distance from the lidar where wind speed data are accurately retrieved. It means that, at this distance, a sufficient number of emitted laser photons are backscattered and received by the lidar. Understanding of the propagation of the laser through the atmosphere, and particularly the backscattering and extinction processes from aerosols, is therefore important to estimate the metrological performances of a CWDL instrument. The range is directly related to specific instrument characteristics and atmospheric content, such as the aerosols type, size, and density distributions. Associated with the measurement range is the notion of data availability, which can be defined, at a given range and over a time period, as the percentage number of data retrieved correctly by the CWDL over the total number of measurement attempts.This paper proposes a new approach to predict the CWDL data availability and range of measurement using both instrumental simulation and atmospheric observations of aerosol optical properties from weather stations and simulations. This method is applied in several CWDL measurement campaigns during which estimated data availabilities and ranges are compared with the observations. It is shown that it is fairly possible to anticipate the data availability and the range coverage of CWDL technology at any site of interest where atmospheric data are available. The method also offers an additional way to diagnose the operation of the instrument and will help in the design of future instruments.

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Parallel computing for finite element structural analysis using conjugate gradient method based on domain decomposition

Journal of Shanghai University (English Edition) ◽

10.1007/s11741-006-0049-y ◽

2006 ◽

Vol 10 (6) ◽

pp. 517-521

Author(s):

Chao-jiang Fu ◽

Wu Zhang

Keyword(s):

Finite Element ◽

Parallel Computing ◽

Structural Analysis ◽

Domain Decomposition ◽

Conjugate Gradient Method ◽

Conjugate Gradient ◽

Gradient Method

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Issues Involved in the Definition and Classification of Chronic Health Conditions

PEDIATRICS ◽

10.1542/peds.91.4.787 ◽

1993 ◽

Vol 91 (4) ◽

pp. 787-793 ◽

Cited By ~ 1

Author(s):

Ellen C. Perrin ◽

Paul Newacheck ◽

I. Barry Pless ◽

Dennis Drotar ◽

Steven L. Gortmaker ◽

...

Keyword(s):

Chronic Conditions ◽

Research Policy ◽

Age Groups ◽

Health Condition ◽

Children And Families ◽

New Approach ◽

Time Period ◽

Definition Of ◽

Use Of Medical Services

The need for a widely applicable definition of chronic conditions for research, policy, and program development has led to an extensive review of the development of such definitions, the considerations involved in their use, and some recommendations for a new approach. This paper examines some of the methodologic and conceptual issues related to defining and classifying chronic conditions and describes some consequences resulting from decisions made about these issues. While most examples are taken from child health applications, the basic concepts apply to all age groups. The dominant method for identifying and classifying children as having a chronic condition has relied on the presence of an individual health condition of lengthy duration. This condition-specific or "categorical" approach has increasingly seemed neither pragmatically nor conceptually sound. Thus, the development of a "generic" approach, which focuses on elements that are shared by many conditions, children, and families, is recommended. Such a definition might reflect the child's functional status or ongoing use of medical services over a specified time period. In addition, it is suggested that conditions be classified based on the experience of individual children, thus emphasizing the tremendous variability in expression of seemingly similar conditions.

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