Many service systems exhibit service slowdowns when the system is congested. Our goal in this paper is to investigate this phenomenon and its effect on system performance. We modify the Erlang-A model to account for service slowdowns and carry out the performance analysis in the Quality-and-Efficiency Driven (QED) regime. We find that when the load sensitivity is low, the system can achieve QED...

Many service systems exhibit service slowdowns when the system is congested. Our goal in this paper is to investigate this phenomenon and its effect on system performance. We modify the Erlang-A model to account for service slowdowns and carry out the performance analysis in the Quality-and-Efficiency Driven (QED) regime. We find that when the load sensitivity is low, the system can achieve QED...

The phenomenon of dynamic stabilization of the inverted rigid planar pendulum whose pivot is forced to oscillate at a high frequency in the vertical direction is revisited. This intriguing nonlinear physical system is analyzed in the paper using time-scale separation and averaging. On this basis, a simple and clear physically meaningful explanation of the phenomenon is presented, followed by th...

We define the logit dynamic for games with continuous strategy spaces and establish its fundamental properties , i.e. the existence, uniqueness and continuity of solutions. We apply the dynamic to the analysis of the Burdett and Judd (1983) model of price dispersion. Our objective is to assess the stability of the logit equilibrium corresponding to the unique Nash equilibrium of this model. Alt...

Intrinsic localized mode (ILM) is spatially localized and temporally periodic oscillation in nonlinear coupled oscillators. We numerically investigate the dynamical stability of ILMs in a microcantilever array, in which ILMs were experimentally observed by M. Sato et al. It is found that the stability change of ILMs is due to the ratio in nonlinear potentials. This phenomenon also occurs in the...

We approximate a fuzzy almost quadratic function by a quadratic function in a fuzzy sense. More precisely, we establish a fuzzy Hyers–Ulam–Rassias stability of the quadratic functional equation f(x + y) + f(x − y) = 2f(x) + 2f(y). Our result can be regarded as a generalization of the stability phenomenon in the framework of normed spaces. We also prove a generalized version of fuzzy stability o...

Co-doping of yttrium doped mixed barium cerate/zirconate perovskite (BCZY) with small amounts of Pr (BCZYP) substantially increases electrical conductivity while retaining structural and chemical stability. BCZYP is predominantly a proton conductor at temperatures up to 600-650 ̊C, whereas it is a mixed proton/oxide ion/electron conductor at higher temperatures. The co-doped BCZYP perovskite can...

We determine some stability results concerning the pexiderized quadratic functional equation in non-Archimedean fuzzy normed spaces. Our result can be regarded as a generalization of the stability phenomenon in the framework of L-fuzzy normed spaces. AMS Mathematics Subject Classification (2010): 00A11; Primary 46S40; Secondary 39B52, 39B82, 26E50, 46S50.

We study the phenomenon of increasing stability of the diffusion and absorption coefficients in the diffuse equation. We derive some bounds which can be viewed as an evidence of increasing stability when the frequency is growing. These bounds hold under a-priori assumptions on the diffusion and absorption coefficients.

Despite providing robustness, high-gain observers impose a peaking phenomenon, which may cause instability, on the system states. In this paper, an adaptive saturation is proposed to attenuate the undesirable mentioned phenomenon in high-gain observers. A real-valued and differentiable sigmoid function is considered as the saturating element whose parameters (height and slope) are adaptively tu...