a state-adaptive access control model for web-based idrs system

Huazhong Univ Sci & Technol, Natl Tech Univ Ukraine, Huazhong Normal Univ, Harbin Inst Technol, IEEE Ukraine Sect, I& M/CI Joint Chapter

Influence of Inter-Fiber Spacing and Interfacial Adhesion on Failure of Multi-Fiber Model Composites: Experiment and Numerical Analysis

The uniaxial tension experiments on glass-fiber-reinforced epoxy matrix composites reveal that the fragmentations of fibers display vertically aligned fracture, clustered fracture, coordinated fracture, and random fracture with the increase of inter-fiber spacing. The finite element analysis indicates that the fragmentations of fibers displaying different phenomena are due to the stress concentration as well as the inherent randomness of fiber defects, which is the dominant factor. The experimental results show that matrices adjacent to the fiber breakpoints all exhibit birefringent-whitening patterns for the composites with different interfacial adhesion strengths. The larger the extent of the interfacial debonding, the less the domain of the birefringent-whitening patterns. The numerical analysis indicates that the orientation of the matrix adjacent to a fiber breakpoint is caused by the interfacial shear stress, resulting in the birefringent-whitening patterns. The area of shear stress concentrations decides on the domain of the birefringent-whitening patterns.

Self-organized Criticality Model for Ocean Internal Waves

In this paper, we present a simple spring-block model for ocean internal waves based on the self-organized criticality (SOC). The oscillations of the water blocks in the model display power-law behavior with an exponent of -2 in the frequency domain, which is similar to the current and sea water temperature spectra in the actual ocean and the universal Garrett and Munk deep ocean internal wave model [Geophysical Fluid Dynamics 2(1972) 225; J. Geophys. REs. 80 (1975) 291]. The influence of the ratio of the driving force to the spring coefficient to SOC behaviors in the model is also discussed.