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1.

In the present work, radon concentrations were measured in surface and underground water samples in Faridabad District of Southern Haryana, India using an active radon monitor based on alpha scintillation technique and results have been inter-compared. The average radon concentration in the underground water samples was observed to be 4 times higher than in the surface water samples. The estimated annual effective dose varied from 5.7 to 58.5 μSvy?1 with an average of 24.2 μSvy?1 for underground water samples and 1.1 to 12.5 μSvy?1 with an average of 6.7 μSvy?1 for surface water samples. The estimated annual effective dose for both type of samples was found to be less than 0.1 mSvy?1, which is the safe limit as suggested by World Health Organisation and EU Council.

  相似文献   
2.
Journal of Thermal Analysis and Calorimetry - Here, MHD stagnation point flow of non-Newtonian fluid over a stretchable surface is considered. Process of modeling is characterized for basic...  相似文献   
3.
In-situ measurements of the viscosity and density of small volumes of liquids are required in several industrial applications. MEMS sensors deploying vibrating microstructures constitute an attractive alternative given the significant impact of the surrounding liquid on their dynamic behavior. In this work, we combine physics-based modeling approaches and deep learning techniques to simultaneously estimate the density and viscosity of liquids from the resonance frequencies and quality factors of immersed microcantilevers. The physics-based model is first validated by comparing the simulated resonance frequencies and quality factors of immersed microcantilevers to those obtained from experiments conducted on a large variety of liquids. Then, we use the simulations results to train deep neutral networks to learn the mapping from the data space to the parameter space. The deep learning method shows high prediction accuracy provided that there is enough independent input data, shows no bias in the predicted values, and provides the results instantaneously. The optimal accuracy in the estimation of the liquid viscosity and density is achieved when the first resonance frequency and corresponding quality factor are used as inputs.  相似文献   
4.
In this paper we consider the homotopy analysis transform method (HATM) to solve the time fractional order Korteweg-de Vries (KdV) and Korteweg-de Vries-Burger’s (KdVB) equations. The HATM is a combination of the Laplace decomposition method (LDM) and the homotopy analysis method (HAM). The fractional derivatives are defined in the Caputo sense. This method gives the solution in the form of a rapidly convergent series with h-curves are used to determine the intervals of convergent. Averaged residual errors are used to find the optimal values of h. It is found that the optimal h accelerates the convergence of the HATM, with the rate of convergence depending on the parameters in the KdV and KdVB equations. The HATM solutions are compared with exact solutions and excellent agreement is found.  相似文献   
5.
In the present paper, we have investigated the Friedmann-Robertson-Walker (FRW) model in viable f(R, T) gravity with f(R, T) function proposed as f(R,T)=R+ξT1/2, where ξ is an arbitrary constant, R is the scalar curvature and T is the trace of stress energy tensor. Defining the scale factor, the field equations are solved numerically and the energy conditions are analyzed. Further, determining Hubble parameter and deceleration parameter, their present values are estimated. Furthermore, 57 redshift data (42 redshift data from Supernova Cosmology project and 15 redshift data from Calán/ Tolono Supernova survey) are used to estimate the age of the universe and to find the best fit curves for luminosity distance and apparent magnitude.  相似文献   
6.
《Journal of voice》2019,33(6):945.e27-945.e35
Reliability of the GRBAS tool for perceptual evaluation of paediatric voice disorder is measured in this study of children with a history of laryngotracheal reconstruction surgery (LTR). Additionally, the relationship between parent proxy/child self-report of voice-related quality of life with clinician perceptual rating of voice quality is analysed. Eleven children with a history of LTR provided voice recordings following the stimuli set by the CAPE-V protocol. Subjective impact of voice quality on life was measured using the paediatric voice-related quality of life questionnaire. Four trained judges rated the sound files according to both the GRBAS and CAPE-V protocol. Intra-class correlation coefficients were high for both intra-rater and inter-rater judgments across all parameters of the GRBAS protocol, and a strong correlation was found between the grade rating of the GRBAS and the overall severity rating of the CAPE-V. Some elements of parent proxy reporting of voice-related quality of life were significantly negatively correlated with clinician perceptual rating of voice quality, while there was no significant relationship between child self-report and clinician perceptual rating.  相似文献   
7.
Journal of Thermal Analysis and Calorimetry - Modeling and computations are performed to study the ND-Co3O4/EG hybrid nanoliquid mixed convective flow past a vertical porous cylinder. The flow...  相似文献   
8.
Moment-independent importance measures are increasingly used by practitioners to understand how output uncertainty may be shared between a set of stochastic inputs. Computing Borgonovo's sensitivity indices for a large group of inputs is still a challenging problem due to the curse of dimensionality and it is addressed in this article. An estimation scheme taking the most of recent developments in copula theory is developed. Furthermore, the concept of Shapley value is used to derive new sensitivity indices, which makes the interpretation of Borgonovo's indices much easier. The resulting importance measure offers a double advantage compared with other existing methods since it allows to quantify the impact exerted by one input variable on the whole output distribution after taking into account all possible dependencies and interactions with other variables. The validity of the proposed methodology is established on several analytical examples and the benefits in terms of computational efficiency are illustrated with real-life test cases such as the study of the water flow through a borehole. In addition, a detailed case study dealing with the atmospheric re-entry of a launcher first stage is completed.  相似文献   
9.
In this paper, a novel Adomian decomposition method (ADM) is developed for the solution of Burgers' equation. While high level of this method for differential equations are found in the literature, this work covers most of the necessary details required to apply ADM for partial differential equations. The present ADM has the capability to produce three different types of solutions, namely, explicit exact solution, analytic solution, and semi-analytic solution. In the best cases, when a closed-form solution exists, ADM is able to capture this exact solution, while most of the numerical methods can only provide an approximation solution. The proposed ADM is validated using different test cases dealing with inviscid and viscous Burgers' equations. Satisfactory results are obtained for all test cases, and, particularly, results reported in this paper agree well with those reported by other researchers.  相似文献   
10.
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