Simple torsion test for shear moduli determination of orthotropic composites

By means of torsion tests performed on test specimens of the same material having a minimum of two different cross sections (flat sheet of different widths), the effective in-plane (G13) and out-of-plane (G23) shear moduli were determined for two composite materials of uniaxial and angleply fiber orientations. Test specimens were 16 plies (nominal 2 mm) thick, 100 mm in length, and in widths of 6.3, 9.5, 12.5, and 15.8 mm. Torsion tests were run under controlled deflection (constant angle of twist) using an electrohydraulic servocontrolled test system. In-plane and out-of-plane shear moduli were calculated from an equation derived in the theory of elasticity which relates applied torque, the torsional angle of twist, the specimen width/thickness ratio, and the ratio of the two shear moduli G13/G23. Results demonstrate that torsional shear moduli, G23 as well as G13, can be determined by simple torsion tests of flat specimens of rectangular cross section. Neither the uniaxial nor angleply composite material were transversely isotropic

Study of strain-hardening near crack tips

Elastic-plastic analysis of stresses and strains near crack tip

Measuring and reporting of intellectual capital: with special reference to commercial banks in Sri Lanka

Importance and growing pressure from shareholders on Intellectual Capital (IC) have been increased over the past decades since managing, measuring and reporting oflC is becoming recognized as an important strategy for transparency and more complete information on the potential profitability and growth of organizations in competitive environment. However, Sri Uinkan companies still give little importance for the measuring and reporting of IC. Thus, the objective of this study is to develop a measuring and reporting framework for IC in Sri Utnkan contexts. This study is conducted over five limited liability commercial banking companies currently operating in Sri Lanka. Study found that measuring and reporting framework for IC was developed in western countries could be applied in Sri Lankan contexts with required adjustments based on stakeholders' prospective and available information

Power smoothing and energy storage sizing of vented oscillating water column wave energy converter arrays

Oscillating water column wave energy converter arrays can be arranged to enhance the energy production and quality of power delivered to the grid. This study investigates four different array configurations of vented oscillating water columns and their effect on power quality and capacity of the energy storage systems required to absorb power fluctuation. Configuring the array of vented oscillating water columns as a nearshore detached breakwater allows combining the benefits of their complementary features. This increases the economic optimization of wave energy converters, paving the path to the energy market. The operations of the integration schemes are evaluated using the results obtained from simulations carried out using MATLAB/Simulink software. Simulation results show that the array of vented oscillating water columns and array of vented oscillating water columns as nearshore detached breakwater configurations increase the quality of power delivered to the grid and reduce the capacity of the energy storage systems required