The Experts below are selected from a list of 10650 Experts worldwide ranked by ideXlab platform

Elizbar Nadaraya - One of the best experts on this subject based on the ideXlab platform.

Hamidreza Bayat - One of the best experts on this subject based on the ideXlab platform.

  • Numerical analysis of effect of nanofluid and fin Distribution Density on thermal and hydraulic performance of a heat sink with drop-shaped micropin fins
    Journal of Thermal Analysis and Calorimetry, 2019
    Co-Authors: Farzin Keshavarz, Arash Mirabdolah Lavasani, Hamidreza Bayat
    Abstract:

    In the present study, the effect of nanofluid and Distribution Density of fin on thermal–hydraulic performance of a heat sink with drop-shaped micropin fins is investigated. Reynolds number is defined based on maximum flow velocity and varies in range of 100 ≤  Re _D ≤ 200 for which, in this range, the flow is laminar and steady. The fins are arranged in two configurations: in-line and staggered. Al_2O_3–water and CuO–water nanofluids with volume fraction of 1% and 4% and Ag_2O–water nanofluid were used to validate the present study. The results showed that using drop-shaped fins instead of circular-shaped fins increases the outlet temperature by 0.6% and decreases the pumping work by 13.3%. Moreover, using Al_2O_3–water nanofluid instead of pure water results in outlet temperature and pump work increases of 0.4% and 1%, respectively. Comparing results of different configurations showed that with low number of fin Density, staggered arrangements provide higher outlet temperature than in-line arrangement. However, for moderate fin Density, in-line arrangements result in higher outlet temperature, and in all fins Distribution Density, staggered arrangements need higher pump work compared to in-line arrangements.

Philippe Du Plessis - One of the best experts on this subject based on the ideXlab platform.

  • a novel approach to estimate the Distribution Density and at sea risks of a centrally placed mobile marine vertebrate
    Biological Conservation, 2018
    Co-Authors: Stephen K Pikesley, Pierre Didier Agamboue, Jean Pierre Bayet, Jean Noel Bibang, Eric Augowet Bonguno, Francois Boussamba, Annette C Broderick, Michael S Coyne, Philippe Du Plessis
    Abstract:

    Abstract Formulating management strategies for mobile marine species is challenging, as knowledge is required of Distribution, Density, and overlap with putative threats. As a step towards assimilating knowledge, ecological niche models may identify likely suitable habitats for species, but lack the ability to enumerate species densities. Traditionally, this has been catered for by sightings-based distance sampling methods that may have practical and logistical limitations. Here we describe a novel method to estimate at-sea Distribution and densities of a marine vertebrate, using historic aerial surveys of Gabonese leatherback turtle ( Dermochelys coriacea ) nesting beaches and satellite telemetry data of females at sea. We contextualise modelled patterns of Distribution with putative threat layers of boat traffic, including fishing vessels and large ship movements, using Vessel Monitoring System (VMS) and Automatic Identification System (AIS) data. We identify key at-sea areas in which protection for inter-nesting leatherback turtles could be considered within the coastal zone of Gabonese Exclusive Economic Zone (EEZ). Our approach offers a holistic technique that merges multiple datasets and methodologies to build a deeper and insightful knowledge base with which to manage known activities at sea. As such, the methodologies presented in this study could be applied to other species of sea turtles for cumulative assessments; and with adaptation, may have utility in defining critical habitats for other central-place foragers such as pinnipeds, or sea bird species. Although our analysis focuses on a single species, we suggest that putative threats identified within this study (fisheries, seismic activity, general shipping) likely apply to other mobile marine vertebrates of conservation concern within Gabonese and central African coastal waters, such as olive ridley sea turtles ( Lepidochelys olivacea ), humpback dolphins ( Sousa teuszii ) and humpback whales ( Megaptera novaeangliae ).

Archil Gulisashvili - One of the best experts on this subject based on the ideXlab platform.

  • Asymptotic Behavior of the Stock Price Distribution Density and Implied Volatility in Stochastic Volatility Models
    Applied Mathematics and Optimization, 2010
    Co-Authors: Archil Gulisashvili, Elias M Stein
    Abstract:

    We study the asymptotic behavior of Distribution densities arising in stock price models with stochastic volatility. The main objects of our interest in the present paper are the Density of time averages of the squared volatility process and the Density of the stock price process in the Stein-Stein and the Heston model. We find explicit formulas for leading terms in asymptotic expansions of these densities and give error estimates. As an application of our results, sharp asymptotic formulas for the implied volatility in the Stein-Stein and the Heston model are obtained.

  • Two-sided estimates for stock price Distribution densities in jump-diffusion models
    arXiv: General Finance, 2010
    Co-Authors: Archil Gulisashvili, Josep Vives
    Abstract:

    We consider uncorrelated Stein-Stein, Heston, and Hull-White models and their perturbations by compound Poisson processes with jump amplitudes distributed according to a double exponential law. Similar perturbations of the Black-Scholes model were studied by S. Kou. For perturbed stochastic volatility models, we obtain two-sided estimates for the stock price Distribution Density and compare the tail behavior of this Density before and after perturbation. It is shown that if the value of the parameter, characterizing the right tail of the double exponential law, is small, then the stock price Density in the perturbed model decays slower than the Density in the original model. On the other hand, if the value of this parameter is large, then there are no significant changes in the behavior of the stock price Distribution Density.

Petre Babilua - One of the best experts on this subject based on the ideXlab platform.