Epidemic models with inhomogeneous populations have been used to study major outbreaks and recently Britton and Lindenstrand [5] described the case when latency and infectivity have independent gamma distributions. They found that variability in these random variables had opposite effects on the epidemic growth rate. That rate increased with greater variability in latency but decreased with gre...

We propose a novel SIR epidemic model which is driven by the transmission of infection packets in networks. Specifically, infected nodes generate and deliver infection packets causing the spread of the epidemic, while recovered nodes block the delivery of infection packets, and this inhibits the epidemic spreading. The efficient routing protocol governed by a control parameter α is used in the ...

The effect of finiteness in degree number is analyzed on a growing network. The dynamics is governed by a rule where the degree number increases under a scheme similar to the Malthus-Verhulst model in the context of population growth. One notices that the second moment of degree is closely related to the linking probability of this growing network. The degree distribution is analyzed in both st...

Cells exhibit a high degree of variation in levels of gene expression, even within otherwise homogeneous populations. The standard model to describe this variation centers on a gamma distribution driven by stochastic bursts of translation. Stochastic bursting, however, cannot account for the well-established behavior of strong transcriptional repressors. Instead, it can be shown the very comple...

The real options technique has emerged as an evaluation tool for investment under uncertainty. It explicitly recognizes future decisions, and the exercise strategy is based on the optimal decisions in future periods. This paper employs the optimal stopping policy derived from real options approach to analyze and evaluate genetic algorithms, specifically for the new branches namely Estimation of...

It is widely known that shifts of cohort fertility schedule can produce misleading trends in period TFR. This note shows that such a “tempo bias” can occur in age-specific mortality as well: if the age distribution of cohort deaths shifts toward older (younger) ages, the period age-specific death rate is biased downward (upward). 1 Laboratory of Populations, Rockefeller University, 1230 York Av...

Disease spread in most biological populations requires the proximity of agents. In populations where the individuals have spatial mobility, the contact graph is generated by the “collision dynamics” of the agents, and thus the evolution of epidemics couples directly to the spatial dynamics of the population. We first briefly review the properties and the methodology of an agent-based simulation...

We propose using the so called Royal Road functions as test functions for cooperative co-evolutionary algorithms (CCEAs). The Royal Road functions were created in the early 90’s with the aim of demonstrating the superiority of genetic algorithms over local search methods. Unexpectedly, the opposite was found to be true. The research deepened our understanding of the phenomenon of hitchhiking wh...

Deepening our understanding of the characteristics and behaviors of population-based search algorithms remains an important ongoing challenge in Evolutionary Computation. To date however, most studies of Evolutionary Algorithms have only been able to take place within tightly restricted experimental conditions. For instance, many analytical methods can only be applied to canonical algorithmic f...

We proposed a deterministic multidimensional growth model for small-world networks. The model can characterize the distinguishing properties of many real-life networks with geometric space structure. Our results show the model possesses small-world effect: larger clustering coefficient and smaller characteristic path length. We also obtain some accurate results for its properties including degr...