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The buck converter is one of the DC/DC converters that are often used as power supplies and high energy conversion. These controllers are used in electronic devices to regulate the output voltage against change in the input voltage and load current. This leads to the requirement of an efficient control methodology to meet real-time demand. It is found in many works of literature that satisfactory performance in buck converter’s dynamic behavior using genetic algorithm controlling techniques, but the appearance of the transient with large overshoots and the ripple output voltage is not focused. The main reason for such a problem is the improper selection of capacitance values. In this work, to address such issues, along with the PID controller gain values and capacitance selection also be considered in multi-objective problems. The optimization is carried out using the NSGA-II and modified NSGA-II algorithm. This paper also presents a comparison of these algorithms’ performance in terms of time-domain specifications and ripple voltage. Simulated outputs exhibit that the controller based on MNSGA-II for buck converter gives better performance than NSGA-II-based controller and results compared with the existing wok. The MNSGA–II-based PID controller for buck converted validated in the real-time environment also.

AbstractThis work investigates the effect of critical properties on aged transformer oil with various additives such as semiconductive nanoparticles, natural and synthetic antioxidants. The additives are added with aged transformer oil in different fraction with the objective to enhance the critical properties of oil and eliminating hazardous disposal. The critical properties like breakdown voltage, flashpoint, firepoint and viscosity of the samples before and after treatment are measured according to IEC and ASTM standards. Impressively it is found that semiconductive nanoparticles, natural and synthetic antioxidants improve the critical properties of aged transformer oil to specified standard. The suitable fraction to which the sample shows constructive result is reported. In addition to that, the above treatment process can be implemented both in the sense of economic retreatment and environmental safety margin.

We introduce the notions of expansion α of α -open sets and α -expansion α -continuous mappings in topological spaces. The main result of this paper is that a map f is α -continuous if and only if it is α -expansion α -continuous and ℬα -expansion α -continuous, where α , ℬα are two mutually dual expansions.

In comparisons across Drosophilaspecies, faster pre-adult development is phenotypically correlated with increased pre-adult competitive ability, suggesting that these two traits may also be evolutionary correlates of one another. However, correlations between traits within- and among- species can differ, and in most cases it is the within-species genetic correlations that are likely to act as constraints on adaptive evolution. Moreover, laboratory studies on Drosophila melanogasterhave shown that the suite of traits that evolves in populations subjected to selection for faster development is the opposite of the traits that evolve in populations selected for increased pre-adult competitive ability. This observation led us to propose that, despite having a higher carrying capacity and a reduced minimum food requirement for completing development than controls, D. melanogasterpopulations subjected to selection for faster development should have lower competitive ability than controls owing to their reduced larval feeding rates and urea tolerance. Here, we describe results from pre-adult competition experiments that clearly show that the faster developing populations are substantially poorer competitors than controls when reared at high density in competition with a marked mutant strain. We briefly discuss these results in the context of different formulations of density-dependent selection theory.

Commercial exploitation of lobsters from the Indian seas began in the 1950s. Annual landings have been declining from a peak of 4075 t in 1985 to 1364 t in 2002. Major fisheries were located on the north-west, south-west, and south-east coasts. Among the 12 species recorded, only four species of spiny lobsters (three littoral and one deep sea) and one species of slipper lobster are commercially important. At Kayalpattinam and Tharuvaikulam, on the south-east coast, lobster landings sharply declined for the gill-net fishery. Of the two species that contributed to the fishery, Panulirus ornatus and Panulirus homarus, the latter has been more affected owing to high vulnerability to fishing activities. Catch composition analysis of the trammel-net fishery showed that 35% of the landings consisted of P. homarus in the size range of 23-50 mm carapace length. On the north-west coast, the spiny lobster Panulirus polyphagus and the slipper lobster Thenus orientalis are incidentally caught in trawl nets. However, the fishery for T. orientalis in the waters off Mumbai lasted only up to 1994. Large-scale exploitation of spawning females, which formed 60% of the total catch, might have been detrimental to the recruitment process resulting in rapid decline and total collapse of the fishery. Abundance of P. polyphagus reached its maximum during September, constituting 23% of the average annual landing during 1988-2002. A high exploitation ratio (>0.7) indicated over-fishing of the stock. Repeated spawning and high annual egg production are probably responsible for sustaining the stock, despite over-exploitation. Major problems confronting the resource management of the multi-gear and multi-species lobster fisheries in India are discussed. An operational project, involving fisher community, has been taken up for creating awareness of the need for sustainable exploitation of the resource. Regulatory measures, such as closure of the fishery during the peak of the breeding season, ban on trammel-net, mandatory release of egg-bearing lobsters, and establishment of lobster sanctuaries are suggested to the State Governments for implementation.

The aim of this paper is to give a decomposition of a weaker form of continuity, namely gα**-continuity by providing the concepts of K-sets and K-continuity.

Both strong directional selection and faster development are thought to destabilize development, giving rise to greater fluctuating asymmetry (FA), although there is no strong empirical evidence supporting this assertion. We compared FA in sternopleural bristle number in four populations ofDrosophila melanogastersuccessfully selected for faster development from egg to adult, and in four control populations. The fraction of perfectly symmetric individuals was higher in the selected populations, whereas the FA levels did not differ significantly between selected and control populations, clearly indicating that directional selection for faster development has not led to increased FA in sternopleural bristle number in these populations. This may be because: (i) development time and FA are uncorrelated, (ii) faster development does result in FA, but selection has favoured developmentally stable individuals that can develop fast and still be symmetrical, or (iii) the increased fraction of symmetric individuals in the selected populations is an artifact of reduced body size. Although we cannot discriminate among these explanations, our results suggest that the relationship between development time, FA and fitness may be far more subtle than often thought.

Four large (n > 1000) populations of Drosophila melanogaster, derived from control populations maintained on a 3 week discrete generation cycle, were subjected to selection for fast development and early reproduction. Egg to eclosion survivorship and development time and dry weight at eclosion were monitored every 10 generations. Over 70 generations of selection, development time in the selected populations decreased by approximately 36 h relative to controls, a 20% decline. The difference in male and female development time was also reduced in the selected populations. Flies from the selected populations were increasingly lighter at eclosion than controls, with the reduction in dry weight at eclosion over 70 generations of selection being approximately 45% in males and 39% in females. Larval growth rate (dry weight at eclosion/development time) was also reduced in the selected lines over 70 generations, relative to controls, by approximately 32% in males and 24% in females. However, part of this relative reduction was due to an increase in growth rate of the controls populations, presumably an expression of adaptation to conditions in our laboratory. After 50 generations of selection had elapsed, a considerable and increasing pre- adult viability cost to faster development became apparent, with viability in the selected populations being about 22% less than that of controls at generation 70 of selection.

Experiments were done with three size groups of Tilapia mossambica(Peters) to study the rate of energy intake, absorption and conversion and absorption efficiency and conversion efficiency. Experimental animals were fed with beef ad libitumfor a period of 40 days. It was found that the rates of intake, absorption and conversion of energy were inversely related to size, whereas efficiencies of absorption and conversion were directly related to size. The reason for the marked difference in the efficiency of energy conversion between small and large size groups is discussed.

We introduce the notions of expansion 𝒜α of α-open sets and 𝒜α-expansion α-continuous mappings in topological spaces. The main result of this paper is that a map f is α-continuous if and only if it is 𝒜α-expansion α-continuous and ℬα-expansion α-continuous, where 𝒜α, ℬα are two mutually dual expansions.