The high expectations of performance and availability for wireless mobile systems has presented great challenges in the modelling and design of fault tolerant wireless systems. The proper modelling methodology to study the degradation of such systems is so-called performability modelling. In this paper, we give overview of approaches for the construction and the solution of performability model...

Due to the fast increase of Internet traffic and the enormous bandwidth potential of alloptical transport networks based on Wavelength Division Multiplexing, an IP-over-WDM network scenario is likely to be widespread in future communication networks. At the same time, IP networks are becoming more and more mission-critical. Hence, it is of paramount importance for IP-over-WDM networks to be abl...

A pplications that call for real-time systems are particularly susceptible to failures. Our challenge is to design, analyze, and build such systems to prevent failures or (at least) to mitigate their effect on operations. The theme articles in this issue, summarized in the box on p. 14, explore different ways to meet this challenge. What differentiates the development of real-time systems softw...

In this paper an efficient high step-up converter with a coupled- inductor with soft- switching operation is presented. The proposed topology includes a coupled-inductor boost converter for raising the voltage gain. Moreover, a simple auxiliary resonant circuit composed of an auxiliary switch, a clamping diode and a resonant tank (inductor, capacitor), is adopted in this paper. The coupled-indu...

conventional implant dentistry has been limited to healed edentulous ridges with adequate bone. predictable success rates resulted in using dental implants in compromised situations such as insertion into old infected sites or near to pathological areas. there is significant data about marginal bone loss and lack of osseointegration around the neck of implants. however, the data about peri apic...

In this paper, a new optimal policy is introduced to determine, adapt, and protect the Generalized MultiProtocol Label Switching (GMPLS) network topology based on the current traffic load. The Integrated Traffic Engineering (ITE) paradigm provides mechanisms for dynamic addition of physical capacity to optical networks. In the absence of such mechanisms, the rejection of incoming requests may b...

Interference between tasks in a task-switching situation was interpreted in terms of theoretical models of time-sharing. Controlled processing of two separate tasks in a time-sharing situation was hypothesized to require a strategy of management whose ease of execution depends on the complexity of the task involved. Switching from one task to the other requires activation of the resources requi...

This paper investigates the problem of dynamic survivable lightpath provisioning against single node/link failures in optical mesh networks employing wavelength-division multiplexing (WDM). We present a new approach to provisioning lightpath requests according to their differentiated quality-of-protection (QoP) requirements. We focus on one of the most important QoP parameters, namely protectio...

This work addresses the problem of state estimation for Markovian switching systems with unknown transition probability matrix (TPM) of the embedded Markov chain governing the switching. Under the assumption of constant but random TPM, an approximate recursion of the TPM’s posterior probability density function (PDF) within the Bayesian framework is obtained. This general PDF recursion is then ...

As modern technologies continue to scale the supply voltage to reduce power consumption, the noise tolerance of these designs also decrease. Testing these designs with conventional transition delay fault patterns can easily strain the power distribution network of the chip beyond the intended design specification due to higher-than-average functional switching activity and the lower noise toler...