Two-dimensional burst identification codes and their use in burst correction

A new class of codes, called burst identification codes, is defined and studied. These codes can be used to determine the patterns of burst errors. Two-dimensional burst correcting codes can be easily constructed from burst identification codes. The resulting class of codes is simple to implement and has lower redundancy than other comparable codes. The results are pertinent to the study of radiation effects on VLSI RAM chips, which can cause two-dimensional bursts of errors

Shear strengthening of reinforced concrete continuous beams

This paper presents the results of an experimental investigation to evaluate the contribution of carbon-fibre-reinforced polymer sheets in enhancing the shear strength of continuous reinforced concrete beams. A total of five, two-span concrete continuous beams with rectangular cross-section were tested. One beam without strengthening was used as the control and the other four beams were strengthened with different arrangements of polymer sheets. The variables selected were various wrapping schemes and anchorage length of the polymer sheet. The aim was to develop a better understanding of the shear contribution of polymer and to investigate the potential for cost savings by minimising the area of externally bonded polymer sheets. Test results were compared with four existing shear prediction models available in the literature. The results indicate that the polymer sheet significantly enhanced the shear strength of the beams, and that the area of polymer sheet can be minimised with marginal compromise on the shear carrying capacity of strengthened concrete beams

On the existence of optimum cyclic burst-correcting codes

It is shown that for each integer b >= 1 infinitely many optimum cyclic b-burst-correcting codes exist, i.e., codes whose length n, redundancy r, and burst-correcting capability b, satisfy n = 2^{r-b+1} - 1. Some optimum codes for b = 3, 4, and 5 are also studied in detail

System Identification and Seismic Performance Evaluation of Earth Dams

A system identification technique is developed to provide dynamic properties of earth dams from their seismic records. The technique is utilized to assess the capabilities and limitation of analytical models in terms of dynamic nonlinear constitutive relationships as well as damping. The technique is based on the least square method using Gaussian hypothesis. Earth dams are modeled as a three-dimensional nonhomogeneous visco-elasto-plastic soil structure. The forward problem is solved using a Galerkin-Ritz formulation in which the solution is expanded using basis function, which is selected to be the eigenmodes. The spatial variation of the excitation is considered by using global shape functions defined on the boundary domain to interpolate the input motion on the dam boundaries using recorded motion at discrete locations. The constitutive model is used to accommodate the nonlinear path dependent behavior of the dam material as well as coupling between different constituent of the soil mixture. The model is implemented using Druker-Prager multi-yield surface model and linear Kelvin-Voigt model. Application to instrumented dams, in recent earthquake, showed significant match between the recorded response and the optimal estimated response