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The work reported in present study deals with the development of a novel stochastic model and estimation of parameters to assess reliability characteristics for a turbogenerator unit of thermal power plant under classical and Bayesian frameworks. Turbogenerator unit consists of five components namely turbine lubrication, turbine governing, generator oil system, generator gas system and generator excitation system. The concepts of cold standby redundancy and Weibull distributed random variables are used in development of stochastic model. The shape parameter for all the random variables is same while scale parameter is different. Regenerative point technique and semi-Markov approach are used for evaluation of reliability characteristics. Sufficient repair facility always remains available in plant as well as repair done by the repairman is considered perfect. As the life testing experiments are time consuming, so to highlight the importance of proposed model Monte Carlo simulation study is carried out. A comparative analysis is done between true, classical and Bayesian results of MTSF, availability and profit function. [ABSTRACT FROM AUTHOR]

Metaheuristic techniques have been utilized extensively to predict industrial systems' optimum availability. This prediction phenomenon is known as the NP-hard problem. Though, most of the existing methods fail to attain the optimal solution due to several limitations like slow rate of convergence, weak computational speed, stuck in local optima, etc. Consequently, in the present study, an effort has been made to develop a novel mathematical model for power generating units assembled in sewage treatment plants. Markov birth-death process is adopted for model development and generation of Chapman-Kolmogorov differential-difference equations. The global solution is discovered using metaheuristic techniques, namely genetic algorithm and particle swarm optimization. All time-dependent random variables associated with failure rates are considered exponentially distributed, while repair rates follow the arbitrary distribution. The repair and switch devices are perfect and random variables are independent. The numerical results of system availability have been derived for different values of crossover, mutation, several generations, damping ratio, and population size to attain optimum value. The results were also shared with plant personnel. Statistical investigation of availability results justifies that particle swarm optimization outdoes genetic algorithm in predicting the availability of power-generating systems. In present study a Markov model is proposed and optimized for performance evaluation of sewage treatment plant. The developed model is one that can be useful for sewage treatment plant designers in establishing new plants and purposing maintenance policies. The same procedure of performance optimization can be adopted in other process industries too. [ABSTRACT FROM AUTHOR]

In plants, the enzyme CCD8 (carotenoid cleavage dioxygenase 8) is involved in the synthesis of an important hormone, strigolactone, and therefore, plays an important role in controlling growth and development. Using cDNA and protein sequence derived from the gene ZmCCD8 from maize, we identified putative orthologs of the gene encoding CCD8 in six other monocots and eight dicots; the sequence similarity ranged from 52–75.9% at the gene level and 60.9–93.7% at the protein level. The average length of the gene was ~3.3 kb (range: 2.08 to 3.98 kb), although the number of introns within the genes differed (4 or 5 in dicots and 3 or 4 in monocots, except in T. urartu with 6 introns). Several cis-acting regulatory elements were identified in the promoters of CCD8 genes, which are known to respond to biotic and abiotic stresses. The N-terminal end (up to ~70 amino acids) of CCD8 proteins was highly variable due to insertions, deletions and mismatches. The variation in genes and proteins were particularly conspicuous in T. urartu and Ae. tauschii among the monocots and A. thaliana and P. persica among the dicots. In CCD8 proteins, 12 motifs were also identified, of which 6 were novel; 4 of these novel motifs occurred in all the 15 species. The 3D structures of proteins had the characteristic features of the related enzyme apocarotenoid oxygenase (ACO) of Synechocystis (a representative of cyanobacteria). The results of qRT-PCR in wheat revealed that under phosphorous (P)-starved condition (relative to expression under optimum P used as control), the expression of TaCCD8 genes increased ~37 fold in root tissue of the cultivar C306 and ~33 fold in shoot tissue of the cultivar HUW468 (the two cultivars differed in their P-use efficiency). This suggested that expression of TaCCD8 genes is genotype-dependent and tissue-specific and is regulated under different levels of P supply. [ABSTRACT FROM AUTHOR]