A telecommunication network is survivable if, following an arc failure, the interrupted traac can be redirected through the network via existing excess capacity. The standard survivability problem consists in nding the least cost investment in spare capacity to allow rerouting of a given base traac. In this paper we consider the more involved problem of simultaneously designing the base traac a...

We have measured the opioid receptor reserve in the guinea pig ileum myenteric plexus by means of the site-directed alkylating agent, beta-chlornaltrexamine. Treatment of the tissue with low (less than 10 nM) concentrations of beta-chlornaltrexamine caused a parallel shift of the log concentration-response curves for both normorphine and dynorphin A-(1-13). Analysis of the resulting curves indi...

Budgeting for maintenance and repair When we purchase a motor vehicle, we understand that we will have recurring costs for maintenance, theft and accident insurance, cleaning, parking, etc. The same is true for ophthalmic equipment since it costs money to operate and to maintain during its life cycle. On average, the original purchase cost only makes up about twenty per cent of the entire life ...

Future reliability of general-purpose processors (GPPs) is threatened by a combination of shrinking transistor size, higher clock rates, reduced supply voltages, and other factors. It is predicted that the occurrence of arbitrary transient faults, or soft errors, wi l l dramatically increase as these trends continue. In this papec we develop and evaluate u fault-tolerant niicroprocessor archite...

Intermittent demand patterns are very difficult to forecast and they are, most commonly, associated with spare parts’ requirements. Most research in this area focuses on the control of inventories assuming that an appropriate estimator is in place to forecast demand and that the demand is represented by one of the standard statistical distributions. The choice of a demand distribution has an im...

“Spare parts surgery” is well-described in the plastic surgery literature. In the setting of trauma, otherwise discarded parts can be utilized for reconstruction resulting in a superior functional and aesthetic outcome for the patient. We describe the use of spare part surgery in order to preserve a functional knee articulation in a patient undergoing amputation for compartment.

Ex vivo experiments have strangely shown that inhibition or stimulation of NAD metabolism can be neuroprotective. In this issue of Cell Metabolism, Brown et al. (2014) demonstrate that cochlear NAD is diminished by deafening noise but protected by nicotinamide riboside or WldS mutation. Hearing protection by nicotinamide riboside depends on Sirt3.

Arow of shiny new vehicles ranging from camper vans to sports cars sits in front of the Vancouver General Hospital, beneath a billboard advertising them as prizes in the hospital’s latest lottery campaign. Downtown, St. Paul’s Hospital has just raffled off a $350 000 condominium. This highly successful venture, now in it’s eighth year, involves the annual sale of 10 000 tickets for $100 each, m...

generally, a typical problem which is crucial in a manufacturing system is increasing the production rate.  to cope with the problem, different types of techniques are used in companies by trial and error which imposes high costs on them. using simulation as a tool for assessing the effect of alterations on the performance of the overall system might be significant. this paper considers a simul...

In industrial systems some components are kept in spare to cope up with the failures of operating components. The failure of these spares too, significantly affects the functioning and outputs of the system. The current paper investigates a semi-Markov model for a redundant system consisting of two identical units and a repair facility. The system starts operating with one unit in operation and...