Consider a system with N components which are subject to failures and repairs. Suppose that each component has a single operating state denoted by 1 and a single failed state denoted by 0. Let X i (t) be the state of component i at time t and let X(t) = (X 1 (t); : : : ; X N (t)) be the state of the system. deened by (x) = (1 if the system operates in state x 0 if the system is failed in state ...

Repairable systems are either repaired perfectly to a state of as good as new or imperfectly. In this work, a system which undergoes imperfect repair is investigated. A nonlinear mathematical model is formulated for a system with the objective of finding the optimum failure and repair rate with the minimum costs subject to attaining a pre-specified performance level. Two imperfect repair models...

Multiprocessor system models are extensively used in modelling transaction processing systems, nodes in communication networks, and flexible machine shops with groups of machines. Such systems clearly, are prone to break-downs. Even if cover is provided with some probability c, there will be rebooting and/or reconfiguration delays to resume operation following the break-down of a processor. In ...

There has never been a single set of criteria for the ascription of disease. The pathoanatomic view ascribed to Virchow and propounded by Thomas Szasz has coexisted with the patient-centered or phenomenologic view for millennia. Schizophrenia, as well as such entities as idiopathic epilepsy and migraine, may be considered a disease because it entails suffering and incapacity, albeit in the abse...

How can leaders adopt a mindset that maximizes learning, remains responsive to short-term emergent opportunities, and simultaneously strengthens longer-term dynamic capabilities of the organization? This chapter explores the organizational decisions and practices leaders can initiate to extend, strengthen, or transform ‘‘ordinary capabilities’’ (Winter, 2003) into enhanced improvisational compe...