The ternary perovskite system PbTiO3-Bi(Zn1/2Ti1/2)O3-Bi(Mg1/2Ti1/2)O3 was investigated in an attempt to capture the enhanced tetragonality of the PbTiO3-Bi(Zn1/2Ti1/2)O3 binary system at a morphotropic phase boundary (MPB) to improve piezoelectric performance. Results from the (1 x)[0.75 PbTiO3-0.25Bi(Zn1/2Ti1/2)O3]-(x)Bi(Mg1/2Ti1/2)O3 pseudo-binary solution indicate the formation of an MPB-ty...

1 − x)Pb(Mg1/3Nb2/3)O3−xPbTiO3 (x = 0, 5, and 10 mol%) ceramics were prepared using a conventional mixed oxide solid state reaction method. The low-temperature relaxor behavior of (1 − x)Pb(Mg1/3Nb2/3)O3–xPbTiO3 ceramics were examined in the temperature range from 120 to 523 K. A broad dielectric maximum that shifted to higher temperatures with increasing frequency, signified the relaxor-type b...

Duplication is a technique frequently employed to achieve high reliability for a repairable system. Although the philosophy of duplication is that it takes two faults to place a system out of service, there are generally some critical single faults that cause a system failure. This paper considers the effect of such a set of faults on a repairable system's reliability. It is shown that even a s...

This paper introduces a Markov model for a multi-state repairable system in which some states are changeable in the sense that whether those physical states are up or down depends on the immediately preceding state of the system evolution process. Several reliability indexes, such as availability, mean up time, steady-state reliability, are calculated using the matrix method. A sufficient condi...

In this paper the transition probability matrix is used to tackle the problem of the availability of repairable systems. The method is applicable to a system governed by a two-parameter distribution for the life-time and repair-time. It will be concentrated on the Weibull and Gamma distributions without and/or with singularities. The method is involving matrices multiplication of massive size. ...

The inventory management of multi-echelon repairable items systems is a major problem as these items are relatively expensive and slow-moving, so, inventory management can be a real problem due to mathematical complexities. In this work, a study was performed in a complex high-value products manufacturer, whose repairable items are both expensive and critical. Data of parts’ failure, storage an...

Recently, locally repairable codes has gained significant interest for their potential applications in distributed storage systems. However, most constructions in existence are over fields with size that grows with the number of servers, which makes the systems computationally expensive and difficult to maintain. Here, we study linear locally repairable codes over the binary field, tolerating m...

Operational systems consist of components that deteriorate and eventually fail. Upon failure, components are either repaired or replaced. Cheap and critical components are usually replaced, while expensive and non-critical components are repaired several times before complete replacement. In this research work, repairable systems undergoing imperfect repair are examined. In this type of repair,...