Synchronization Probability in Large Random Networks

In a generalized framework, where multi-state and inter-state linkages are allowed, we derive a sufficient condition for the stability of synchronization in a network of chaotic attractors. This condition explicitly relates the network structure and the local and coupling dynamics to synchronization stability. For large Erd\"{o}s-R\'{e}nyi networks, the obtained condition is translated into a lower bound on the probability of stability of synchrony. Our results show that the probability of stability quickly increases as the randomness crosses a threshold which for large networks is inversely proportional to the network size

On the Existence of an MVU Estimator for Target Localization with Censored, Noise Free Binary Detectors

The problem of target localization with censored noise free binary detectors is considered. In this setting only the detecting sensors report their locations to the fusion center. It is proven that if the radius of detection is not known to the fusion center, a minimum variance unbiased (MVU) estimator does not exist. Also it is shown that when the radius is known the center of mass of the possible target region is the MVU estimator. In addition, a sub-optimum estimator is introduced whose performance is close to the MVU estimator but is preferred computationally. Furthermore, minimal sufficient statistics have been provided, both when the detection radius is known and when it is not. Simulations confirmed that the derived MVU estimator outperforms several heuristic location estimators.Comment: 25 pages, 9 figure

Stabilization of Networked Control Systems with Sparse Observer-Controller Networks

In this paper we provide a set of stability conditions for linear time-invariant networked control systems with arbitrary topology, using a Lyapunov direct approach. We then use these stability conditions to provide a novel low-complexity algorithm for the design of a sparse observer-based control network. We employ distributed observers by employing the output of other nodes to improve the stability of each observer dynamics. To avoid unbounded growth of controller and observer gains, we impose bounds on their norms. The effects of relaxation of these bounds is discussed when trying to find the complete decentralization conditions

Isolation and characterization of cellulose synthase gene from Roselle (Hibiscus sabdariffa L.)

Hibiscus sabdariffa (Roselle) has the potential to be an alternative fibre source for cellulose as a strengthening material in polymer composites. A literature survey has shown scant information regarding utilization of this fiber as reinforcing material. Although roselle was hypothesized to be a potential natural fibre source, there is no study focusing on the fundamental genetics underlying the cellulose biosynthesis machinery in roselle. Isolation of CesA gene is important to understand the biosynthesis pathway in roselle. Therefore, the first cellulose synthase gene (HsCesA1) of H. sabdariffa was isolated and characterized. Full-length HsCesA1 cDNA of 3528 bp was isolated using RACE PCR, and the start and stop codons, poly A signal, poly A tail, 3´ UTR and 5´ UTR were identified using in silico analyses. The full-length HsCesA1 gene with a total length of 5489 bp, which consisted of 12 exons, 11-introns and a promoter region of 737 bp was also isolated using PCR walkin and genome walking repectively. Several important and conserved characteristics were predicted in the HsCesA1 deduced amino acid sequence such as Cellulose-synt, Glycosyltransferase family A (GT-A), bcsA, Zn-finger domain, RING/U-box and domains A and B. These predicted characteristics provided evidence that the isolated gene is possibly a CesA and it belongs to the processive class in the glycosyltransferase family A. Semi-quantitative RT-PCR expression study was carried out on both leaf and stem tissues, it was found that HsCesA1 was expressed in both tissue types and it had similar levels of expression in both young tissues. Phylogenetic and Blast analyses also supported that HsCesA1 might play roles in both primary and secondary cell wall depositions. However, further investigations must be carried out to confirm the function of this HsCesA1. We have isolated the first cellulose synthase gene, full-length HsCesA1 cDNA with total length of 3528 bp (accession no: KJ608192) and full length HsCesA1 gene with total length of 5489 bp (accession no: KJ661223). This study generated some genetic information about the structure and putative function of the cellulose synthase gene in the genome of H. sabdariffa. In the other words, this study provides information on the primary structure of the HsCesA1 gene, which is fundamental for working towards understanding the function of the gene in the roselle plant in the future

Bounded Stability in Networked Systems with Parameter Mismatch and Adaptive Decentralized Estimation

Here, we study the ultimately bounded stability of network of mismatched systems using Lyapunov direct method. The upper bound on the error of oscillators from the center of the neighborhood is derived. Then the performance of an adaptive compensation via decentralized control is analyzed. Finally, the analytical results for a network of globally connected Lorenz oscillators are verified.Comment: 6 pages, 3 figures, Accepted and presented in IEEE Conference Allerton 201