670 research outputs found

    Multi Objective Directed Bee Colony Optimization for Economic Load Dispatch With Enhanced Power Demand and Valve Point Loading

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    Earlier economic emission dispatch methods for optimizing emission level comprising carbon monoxide, nitrous oxide and sulpher dioxide in thermal generation, made use of soft computing techniques like fuzzy,neural network,evolutionary programming,differential evolution and particle swarm optimization etc..The above methods incurred comparatively more transmission loss.So looking into the nonlinear load behavior of unbalanced systems following differential load pattern prevalent in tropical countries like India,Pakistan and Bangladesh etc.,the erratic variation of enhanced power demand is of immense importance which is included in this paper vide multi objective directed bee colony optimization with enhanced power demand to optimize transmission losses to a desired level.In the current dissertation making use of multi objective directed bee colony optimization with enhanced power demand technique the emission level versus cost of generation has been displayed vide figure-3 & figure-4 and this result has been compared with other dispatch methods using valve point loading(VPL) and multi objective directed bee colony optimization with & without transmission loss

    Comparative Study on Thresholding

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    Criterion based thresholding algorithms are simple and effective for two-level thresholding. However, if a multilevel thresholding is needed, the computational complexity will exponentially increase and the performance may become unreliable. In this approach, a novel and more effective method is used for multilevel thresholding by taking hierarchical cluster organization into account. Developing a dendogram of gray levels in the histogram of an image, based on the similarity measure which involves the inter-class variance of the clusters to be merged and the intra-class variance of the new merged cluster . The bottom-up generation of clusters employing a dendogram by the proposed method yields good separation of the clusters and obtains a robust estimate of the threshold. Such cluster organization will yield a clear separation between object and background even for the case of nearly unimodal or multimodal histogram. Since the hierarchical clustering method performs an iterative merging operation, it is extended to multilevel thresholding problem by eliminating grouping of clusters when the pixel values are obtained from the expected numbers of clusters. This paper gives a comparison on Otsu’s & Kwon’s criterion with hierarchical based multi-level thresholding

    Numerical investigation of natural convection for vertical flat plate with fins

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    Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.A finite-volume-based computational study of steady laminar natural convection from a finned isothermal vertical plate with different fin arrays has been carried out to determine the heat transfer augmentation factor with different fin aspect ratio, fin spacing and inclination of fin. Heat transfer behaviors with the fins have been analyzed by examining variations of the local and average Nusselt numbers in two- dimensional flow. Four different fin arrays heights (H = 6, 12, 18, 24 mm) and four different angles of inclination ( θ = 45°, 60°,75°, 90°) are considered. In order to understand the heat transfer characteristics of this problem, a total of 96 cases for each of conductive and non- conductive fins are considered. It is found that significant heat transfer augmentation is obtained for conductive (20% higher augmentation factor when the fin aspect ratio is 6, and angle of inclination is 60° and pitch-to-length ratio is 0.2) and non-conductive fins (10% higher augmentation factor, at fin aspect ratio of 8, angle of inclination at 45° and pitch-to- length ratio at 0.5). A general correlation has been developed to predict the average Nusselt number for fin arrays as a function of different fin configurations.dc201

    Population dynamics and stock assessment of spadenose shark Scoliodon laticaudus Muller and Henle 1839 along Gujarat coast of India

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    423-433Stock assessment of Scoliodon laticaudus Muller and Henle, 1839 was made along with analysis of its few biological characteristics from its commercial landings during 2012-2016 from Gujarat waters of India to understand the population dynamics and stock status of the species. The average annual landing of the species was 5442 t, which constituted about 67% of the total shark landings at Gujarat coast. L∞, K and t0 were estimated as 75.53 cm and 0.54/yr, and -0.4 yr, respectively. Total mortality rate, fishing mortality rate and natural mortality rate were estimated as 1.95 yr-1, 1.04 yr-1 and 0.91 yr-1, respectively. The length at capture (Lc50) and length at maturity (Lm50) were 39.74 cm and 35.79 cm, respectively, which indicate that most of the sharks are exploited after attaining the sexual maturity. Length-weight relationship showed that the growth was isometric. The species was a continuous breeder and showed peak recruitment during September. The current exploitation ratio (Ecur) was found to be 0.53, which is lower than E0.1 estimated for the species using Beverton and Holt yield per recruit analysis. Thompson and Bell prediction model showed that maximum sustainable yield for S. laticaudus could be obtained by increasing fishing effort by almost 2.4 times higher than the present level which would deplete the spawning stock biomass (SSB) to 20%. Maximum economic yield could be obtained by increasing the fishing effort by 1.8 times which would also decrease the SSB, but to a comparatively safer 26.5% level. Considering 30% SSB as a precautionary management reference point, the effort could be increased by 50% exclusively for the sharks to increase the yield and revenue from fishery while maintain SSB at a safer 30% level

    India’s contribution to mitigating the impacts of climate change through vegetation management

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    The changes in natural ecosystems provide opportunity to increase vegetation carbon sink capacity and thereby contribute to mitigation of climate change impacts. The Indian tropics and the large ecological variation within the country afford the advantage of diverse niches and offer opportunities to reveal the role of biotic factors at different levels of organization from populations to ecosystems. The last 4 decades of research and development in the Indian space science community has been primarily application driven in response to the government space programme for national development. The expenditure in R&D over next 5 year suggest that scientific research is higher on the country's agenda. The Indo-UK Terrestrial Carbon Group (IUTCG) comprising both Indian and UK scientists, funded jointly by the Department of Science and Technology, India and the Department of Business, Innovation and Skills organised a workshop to explore ways in which Earth observation data can be effectively utilised in mitigating the impacts of climate change through vegetation management. Effective integration of field observations, collected through various monitoring networks, and satellite sensor data has been proposed to provide country-wide monitoring

    Precise measurement of hadronic tau-decays with an eta meson

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    We have studied hadronic tau decay modes involving an eta meson using 490 fb^{-1} of data collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. The following branching fractions have been measured: B(tau- -> K- eta nu)=(1.58 +- 0.05 +- 0.09)x 10^{-4}, B(tau- -> K- pi0 eta nu)=(4.6 +- 1.1 +- 0.4)x 10^{-5}, B(tau- -> pi- pi0 eta nu)=(1.35 +- 0.03 +- 0.07)x 10^{-3}, B(tau- -> pi- KS eta nu)=(4.4 +- 0.7 +- 0.2)x 10^{-5}, and B(tau- -> K^{*-} eta nu)=(1.34 +- 0.12 +- 0.09)x 10^{-4}. These results are substantially more precise than previous measurements. The new measurements are compared with theoretical calculations based on the CVC hypothesis or the chiral perturbation theory. We also set upper limits on branching fractions for tau decays into K- KS eta nu, pi- KS pi0 eta nu, K- eta eta nu, pi- eta eta nu and non-resonant K- pi^0 eta nu final states.Comment: 24 pages, 7 figure

    Consequences of temperature fluctuations in observables measured in high energy collisions

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    We review the consequences of intrinsic, nonstatistical temperature fluctuations as seen in observables measured in high energy collisions. We do this from the point of view of nonextensive statistics and Tsallis distributions. Particular attention is paid to multiplicity fluctuations as a first consequence of temperature fluctuations, to the equivalence of temperature and volume fluctuations, to the generalized thermodynamic fluctuations relations allowing us to compare fluctuations observed in different parts of phase space, and to the problem of the relation between Tsallis entropy and Tsallis distributions. We also discuss the possible influence of conservation laws on these distributions and provide some examples of how one can get them without considering temperature fluctuations.Comment: Revised version of the invited contribution to The European Physical Journal A (Hadrons and Nuclei) topical issue about 'Relativistic Hydro- and Thermodynamics in Nuclear Physics' guest eds. Tamas S. Biro, Gergely G. Barnafoldi and Peter Va

    Search for Resonant B±K±hK±γγB^{\pm}\to K^{\pm} h \to K^{\pm} \gamma \gamma Decays at Belle

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    We report measurements and searches for resonant B±K±hK±γγB^{\pm} \to K^{\pm} h \to K^{\pm} \gamma \gamma decays where hh is a η,η,ηc,ηc(2S),χc0,χc2,J/ψ\eta,\eta^{\prime},\eta_{c},\eta_{c}(2S),\chi_{c0},\chi_{c2},J/\psi meson or the X(3872) particle.Comment: accepted by Physics Letters

    Study of charmonia in four-meson final states produced in two-photon collisions

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    We report measurements of charmonia produced in two-photon collisions and decaying to four-meson final states, where the meson is either a charged pion or a charged kaon. The analysis is based on a 395fb^{-1} data sample accumulated with the Belle detector at the KEKB electron-positron collider. We observe signals for the three C-even charmonia eta_c(1S), chi_{c0}(1P) and chi_{c2}(1P) in the pi^+pi^-pi^+pi^-, K^+K^-pi^+pi^- and K^+K^-K^+K^- decay modes. No clear signals for eta_c(2S) production are found in these decay modes. We have also studied resonant structures in charmonium decays to two-body intermediate meson resonances. We report the products of the two-photon decay width and the branching fractions, Gamma_{gamma gamma}B, for each of the charmonium decay modes.Comment: 22 pages, 12 figure
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