A new zwitterionic conjugated polyelectrolyte without free counterions has been used as an electron injection material in polymer light-emitting diodes. Both the efficiency and maximum brightness were considerably improved in comparison with standard Ca cathode devices. The devices showed very fast response times, indicating that the improved performance is, in addition to hole blocking, due to...

A feasible and effective self-assembly method to synthesize different scale coordination polymers in highly dilute solution (from nanocrystals to microcrystals and to bulk crystals) without any blocking agent has been described. The growth of crystalline particles was controlled by removing the particles at different reaction times to interrupt the growth at the desired size. The nano and micro...

There have been recent advances in multi-core machines with tens and hundreds of cores, there is an increasing emphasis on the software structure. Many different synchronization mechanism techniques developed to improve performance scalability manycore systems. As non-blocking algorithms are promising overcoming limits traditional lock-based blocking mechanisms, we observing increased usage rat...

The effects joined by vehicular mobility are investigated in the performance analysis of cellular network. The channel holding times induced from mobility and call holding time are approximately modeled by general distribution to reflect an actual situation. We propose an iterative numerical algorithm to compute the performance values of the CAC as the values for a handoff call dropping probabi...

We study queues in tandem with customer deadlines and retrials. We first consider a 2-queue Markovian system with blocking at the second queue, analyze it, and derive its stability condition. We then study a non-Markovian setting and derive the stability condition for an approximating diffusion, showing its similarity to the former condition. In the Markovian setting, we use probability generat...

Accurate, reproducible and comparable measurement of the overheads, communication times and progression behavior of blocking and nonblocking collective operations is a complicated task. Although Different measurement schemes for blocking collective operations are implemented in well-known benchmarks, many of these schemes introduce different systematic errors in their measurements. We character...

We consider a single cell of a multi-service CDMA network, in which some of the service classes are explicit rate controlled. We call these elastic service classes. The instantaneous bit rate of elastic services is dynamically adjusted between a minimum and maximum value such that the system always remains work conserving. We develop a Markov model that allows us to study the impact of such sta...

Firewalls are a crucial building block for securing IP networks. The usage of out-of-band-signaling protocols (such as SIP) for VoIP and multimedia applications requires a dynamic control of these firewalls, which can be implemented using the Simple Middlebox Configuration Protocol (SIMCO). In this paper, we study the performance of SCTP and TCP as transport protocols for the transaction-based ...

We study flow scheduling to lightpaths in an optical flow switching network where flow arrivals are modeled as a time dependent Poisson process and their holding times are Pareto distributed. Scheduling decisions are taken at fixed time intervals (larger than 100 ms) in a central node and scheduled flows cannot be interrupted before their completion. The scheduling problem is represented as a d...

The sensitivity of the performance measures such as the mean and the standard deviation of the queue length and the blocking probability with respect to the moments of the service time are numerically investigated. The steady state distribution of M/G/c queue is approximated by that of the M/PH/c queue where the phase type (PH) distribution is fitted by matching the first three moments of the s...