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Sol–gel dip-coated optical coatings, copper–cobalt oxides on aluminum substrates, were thermally treated at different annealing temperatures in the range 500–650 °C. The resulting films were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV–Vis–NIR spectrophotometry and nanoindentation techniques. The crystallinity of CoCu2O3 enhanced significantly, with increasing annealing temperature from 500 to 650 °C, while the electronic structure and bonding states of the copper–cobalt oxides matrix remained unchanged. UV–Vis–NIR analysis showed that the solar absorptance (α) of the coatings changed with increase of annealing temperature and an optimum α (84.4%) was achieved at 550 °C, which also coincides to the maximum tensile residual stress of the coating. Nanoindentation tests exhibited an increasing trend in both the hardness (H) and elastic modulus (E) of the coatings with increase in annealing temperature, although a slight decrease in the H/E ratio was also observed. The experimental studies were complemented by finite element modeling (FEM). The results showed that, under mechanical loading, the stress deformation and plastic deformation were concentrated within the coating layers. As such, the likelihood of delamination of the coating layer upon unloading would be reduced.

Bufferless fluid flow model (bffm) is widely used in the literature for cell loss analysis. In this paper, we propose an efficient and effective means of investigating cell loss in the bffm. We define the cell loss rate function (clrf) and use it to characterize the cell loss of traffic sources in the bffm. Properties of clrf are discussed. These properties enable us to decompose the complex analysis of the multiplexing of several traffic sources into the simpler analysis of the individual sources. A cell loss upper bound for heterogeneous ON-OFF sources is proposed using clrf. The proposed cell loss upper bound is tighter than that proposed in previous literature. A connection admission control (CAC) scheme using online measurements is designed based on the cell loss upper bound. Extensive simulations are carried out to study the performance of the CAC scheme. Simulation results indicate that the proposed CAC scheme is time-efficient, can ensure QoS guarantee, and is capable of achieving high network utilization. © 2002 Elsevier Science B.V. All rights reserved.

The bufferless fluid flow model (bffm) is often used in the literature for loss performance analysis. In this paper, we propose an efficient and effective means of investigating cell loss using the bffm. We define the cell loss rate function (clrf) and use it to characterize the loss performance of traffic sources in the bffm. Stochastic ordering theory is used to study the clrf. The introduction of the stochastic ordering theory not only simplifies the theoretical analysis but also makes it possible to extend the scope of applications and theoretical analysis presented in this paper. A cell loss upper bound for heterogeneous ON-OFF sources is proposed. The proposed cell loss upper bound is tighter than those previously proposed in the literature. A connection admission control (CAC) scheme using online measurements is designed based on the cell loss upper bound. Extensive simulation is carried out to study the performance of the CAC scheme. Particular attention is paid to the impact of inaccuracies in user-declared traffic parameters on the performance of the CAC scheme. Simulation results indicate that the proposed CAC scheme can ensure QoS guarantee, is robust to inaccuracies in declared traffic parameters, and is capable of achieving high link utilization.