Application Integration Control System for Multi-Scale and Multi-PhysicsSimulation

In the case of long-period and large-scale simulation, unexpected stop which is caused by execution time excess, outage of computers, outage of a network during file transfer and so on, become major issues. To avoid the stop of job execution and file transfer, we have developed Task Flow Control System that is a new control system for application integration with a fault tolerant API. If the computer is outage, the system designates an alternate computer, gathers necessary files and submits a new job. Each scheduler, file transfer and job condition can be flexibly defined in XML. This time, we applied the system to fluid-structure interaction analysis simulation. The result indicates that the system enables a user to easily execute multi-scale and multi-physics simulation using application integration

Studies on the Responses of Multi-degrees of Freedom Systems Subjected to Random Excitation with Applications to the Tower and Pier Systems of Long Span Suspension Bridges

In this paper the responses of multi-degrees of freedom systems with applications to the pier and tower systems of long span suspension bridges due to earthquake motions are studied by the stochastic process theory and the results are compared with the direct-integration. For the present system, foundation conditon coupled with the pier dimensions has significant effects on the structural dynamic characteristics. The response behaviors and then their evaluation become complex for some foundation ranges. Here, on the assumption that the normal mode analysis can be applied, the direct-effects of individual modes and their cross-effects to the dynamic response characteristics are investigated by simulating earthquake motions to a suitable form

Random Response Analysis of a Long-span Suspension Bridge Tower and Pier with Consideration of Nonlinear Foundation

The nonlinear foundation effect upon the response of the tower and pier system of a long-span suspension bridge is investigated by the random vibration theory. As the equivalent linearlization yields the nonproportional damping matrix, the exact response is evaluated both through the frequency domain analysis and the complex mode analysis. Also discussed is the approximate response analysis using classical normal modes for the practical design procedure

Computationally determining the salience of decision points for real-time wayfinding support

This study introduces the concept of computational salience to explain the discriminatory efficacy of decision points which in turn may have applications to providing real-time assistance to users of navigational aids. This research compared algorithms for calculating the computational salience of decision points and validated the results via three methods: high-salience decision points were used to classify wayfinders; salience scores were used to weight a conditional probabilistic scoring function for real-time wayfinder performance classification; and salience scores were correlated with wayfinding-performance metrics. As an exploratory step to linking computational and cognitive salience a photograph-recognition experiment was conducted. Results reveal a distinction between algorithms useful for determining computational and cognitive saliences. For computational salience information about the structural integration of decision points is effective while information about the probability of decision-point traversal shows promise for determining cognitive salience. Limitations from only using structural information and motivations for future work that include non-structural information are elicited

Near Source Strong Ground Motion Simulation for Kocaeli Earthquake (1999)

A near field strong ground motion simulation was carried out due to fault rupturing in the Kocaeli Earthquake (1999). The ground motions are simulated by the convolution scheme in time for source function and in space along rupture direction with the layered soil Green\u27s function method based on the kinematic dislocation model. The effects of the asperities in the fault rupturing are focused considering inhomogeneous rupture mechanism in terms of a multiple asperities. The synthetic motions based on the inversion information from the observed data are compared well with the YPT (Yarimca Petrochemical Complex) record of the Kocaeli Earthquake. The response spectrum results also show good agreement between observed and simulated motions. The wavelet transform analysis is applied to observe the variation of frequency contents with the time for recorded and simulated motions

An Effective Local Absorbing Boundary for 3D FEM Time Domain Analyses

The aim of this paper is to investigate and develop alternative methods for analyzing transient problems in dynamic soil-structure interaction, (SSI) within the FEM context. Development of a simple and efficient FEM procedure for the solution directly in the time domain of SSI problems is the main issue. Considering Direct Method of analysis, a new formulation of local transmitting boundaries for transient three-dimensional (3D) FEM analysis is presented based on the radiation criterion and strength-of- materials theory. These numerical devices can be considered as doubly asymptotic, (DA) approximations and are given in terms of first order differential operators. Different formulations for volume and surface waves are considered. A computer code employing an implicit FEM for solving 3D elastic wave propagation problems is developed to investigate the effectiveness of the proposed boundary conditions, (BC’s). Numerical examples for homogeneous hafspace in full 3D are presented in comparison to extended mesh and fundamental solutions, a classical approach. As the effort for implementing them is the same as for the impedance BC, standard assembly procedure can be used. Due to the local nature they also preserve the overall structure of the global equations of motions

Seismic Analysis Using Synthetic Wave Based on the Dislocation Model to Simulate Ground Motions in the Hyogoken-Nanbu Earthquake 1995

The Green function based on the kinematics dislocation model has been newly developed in association with the convolution scheme in time for source function and in space along rupture direction. Synthetic waves derived from this model are corresponding to the bedrock motion. The ground model is formed with 3D multi-thin layers and the soils are linear material. Inhomogeneous rupture mechanism in faults is considered in terms of multiple asperities gained from the inversion information. In the shallow soils, non-linearity governs the dynamic behavior of the ground. Waves propagate with amplifications and absorption through the soft soil according to the frequency contents. Finite element analysis based on the plastic theory can include the dynamic properties of soils, the surface layer effects and the topographic conditions

Analyzing power in nucleon-deuteron scattering and three-nucleon forces

Three-nucleon forces have been considered to be one possibility to resolve the well known discrepancy between experimental values and theoretical calculations of the nucleon analyzing power in low energy nucleon-deuteron scattering. In this paper, we investigate possible effects of two-pion exchange three-nucleon forces on the analyzing power and the differential cross section. We found that the reason for different effects on the analyzing power by different three-nucleon forces found in previous calculations is related to the existence of the contact term. Effects of some variations of two-pion exchange three-nucleon forces are investigated. Also, an expression for the measure of the nucleon analyzing power with quartet P-wave phase shifts is presented.Comment: 11 pages including 2 eps figures, use epsfig.sty, to appear in Phys. Rev.

BEM-FEM Hybrid Analysis for Topographical Site Response Characteristics

This paper concerns an amplification of seismic ground motions by a certainly shaped surface soil deposits in view of its topographical configuration. Different hybrid methods of the boundary element method (BEM) and the finite element method (FEM) are used for the two-dimensional (2- D) analysis. In the analysis, the far field impedance is first evaluated by BEM then it is incorporated into the near field FEM analysis based on the weighted residual method. The steady state responses for different types of harmonic incident waves are investigated. Some useful findings are pointed out in comparison with the one-dimensional (1-D) results