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On a double integral involving the I-function of two variables
Get PDFIn this paper we establish an interesting double integral involving the I-function of two variables recently introduced in the literature. Since I-function of two variables is a very generalized function of two variables and it includes as special cases many of the known functions appearing in the literature, a number of integrals can be obtained by reducing the I-function of two variables to simpler special functions by suitably specializing the parameters. A few special cases of our result are also discussed
Non-Inflationary Bianchi Type VI0 Model in Rosen’s Bimetric Gravity
Get PDFIn this paper, we have present the solution of Bianchi type VI0 space-time by solving the Rosen’s field equations with massless scalar field φ and with constant scalar potential V(φ) for flat region. It is observed that the scalar field φ is an increasing function of time and affects the physical parameters of the model and leads to non-inflationary type solution of model, which contradicts the inflationary scenario. Other geometrical and physical properties of the model in relation to this non-inflationary model are also studied
Effect of Solid Volume Fraction on Forced Convective Flow of Nanofluid through Direct Absorption Solar Collector
Get PDFThe present work numerically investigates the heat transfer performance and entropy generation of forced convection through a direct absorption solar collector. The working fluid is Cu-water nanofluid. The simulations focus specifically on the effect of solid volume fraction of nanoparticle on the mean Nusselt number, total entropy generation, Bejan number and collector efficiency. Also Isotherms, heat function and entropy generation are presented for various solid volume fraction. The governing partial differential equations are solved using penalty finite element method with Galerkins weighted residual technique. The results show that the mean Nusselt number and mean entropy generation increases as the volume fraction of Cu nanoparticles increases. The results presented in this study provide a useful source of reference for enhancing the force convection heat transfer performance while simultaneously reducing the entropy generation
Soil water content sensor response to organic matter content under laboratory conditions
No full textStudies show that the performance of soil water content monitoring (SWCM) sensors is affected by soil physical and chemical properties. However, the effect of organic matter on SWCM sensor responses remains less understood. Therefore, the objectives of this study are to (i) assess the effect of organic matter on the accuracy and precision of SWCM sensors using a commercially available soil water content monitoring sensor; and (ii) account for the organic matter effect on the sensor’s accuracy. Sand columns with seven rates of oven-dried sawdust (2%, 4%, 6%, 8%, 10%, 12% and 18% v/v, used as an organic matter amendment), thoroughly mixed with quartz sand, and a control without sawdust were prepared by packing quartz sand in two-liter glass containers. Sand was purposely chosen because of the absence of any organic matter or salinity, and also because sand has a relatively low cation exchange capacity that will not interfere with the treatment effect of the current work. Sensor readings (raw counts) were monitored at seven water content levels (0, 0.02, 0.04, 0.08, 0.12, 0.18, 0.24, and 0.30 cm3 cm-3) by uniformly adding the corresponding volumes of deionized water in addition to the oven-dry one. Sensor readings were significantly (p \u3c 0.05) affected by the organic matter level and water content. Sensor readings were strongly correlated with the organic matter level (R2 = 0.92). In addition, the default calibration equation underestimated the water content readings at the lower water content range (\u3c0.05 cm3 cm-3), while it overestimated the water content at the higher water content range (\u3e0.05 cm3 cm-3). A new polynomial calibration equation that uses raw count and organic matter content as covariates improved the accuracy of the sensor (RMSE = 0.01 cm3 cm-3). Overall, findings of this study highlight the need to account for the effect of soil organic matter content to improve the accuracy and precision of the tested sensor under different soils and environmental conditions
Analysis of potential future climate and climate extremes in the brazos headwaters Basin, Texas
No full textTexas\u27 fast-growing economy and population, coupled with cycles of droughts due to climate change, are creating an insatiable demand for water and an increasing need to understand the potential impacts of future climates and climate extremes on the state\u27s water resources. The objective of this study was to determine potential future climates and climate extremes; and to assess spatial and temporal changes in precipitation (Prec), and minimum and maximum temperature (Tmin and Tmax, respectively), in the Brazos Headwaters Basin under three greenhouse gas emissions scenarios (A2, A1B, and B1) for three future periods: 2020s (2011-2030), 2055s (2046-2065), and 2090s (2080-2099). Daily gridded climate data obtained from Climate Forecast System Reanalysis (CFSR) were used to downscale outputs from 15 General Circulation Models (GCMs) using the Long Ashton Research Station-Weather Generator (LARS-WG) model. Results indicate that basin average Tmin and Tmax will increase; however, annual precipitation will decrease for all periods. Annual precipitation will decrease by up to 5.2% and 6.8% in the 2055s and 2090s, respectively. However, in some locations in the basin, up to a 14% decrease in precipitation is projected in the 2090s under the A2 (high) emissions scenario. Overall, the northwestern and southern part of the Brazos Headwaters Basin will experience greater decreases in precipitation. Moreover, precipitation indices of the number of wet days (prec ≥ 5 mm) and heavy precipitation days (prec ≥ 10 mm) are projected to slightly decrease for all future periods. On the other hand, Tmin and Tmax will increase by 2 and 3 °C on average in the 2055s and 2090s, respectively. Mostly, projected increases in Tmin and Tmax will be in the upper range in the southern and southeastern part of the basin. Temperature indices of frost (Tmin \u3c 0 °C) and ice days (Tmax \u3c 0 °C) are projected to decrease, while tropical nights (Tmin \u3e 20 °C) and summer days (Tmax \u3e 25 °C) are expected to increase. However, while the frequency distribution of meteorological drought shows slight shifts towards the dry range, there was no significant difference between the baseline and projected meteorological drought frequency and severity
Mathematical model to study The spread of spilled oil in the soil
Get PDFA mathematical model describing the spread of spilled oil through the soil is discussed. The spread of spilled oil in soil is controlled by the flow of water and is described by multiphase equations. In this context, the two-phase flow characteristics of oil-water flow with varying viscosity in the subsurface coupled to an advective-diffusion equation are examined to study the transport of oil. The terms that model the interaction between the multiple phases are introduced at the boundary, such as the slip condition at the porous-fluid interface, shear stress condition at the fluid-fluid interface, and the continuity of velocity at both the interfaces. The effect of various physical parameters such as Schmidt number, retardation factor, viscosity ratio, porous and slip parameter on the velocity and concentration profiles are discussed in detail with the help of graphs. The surface plots of velocity and concentration of oil against axial distance at different time are also analyzed. The obtained results show that the velocity of oil accelerates linearly with axial length and there is a decrease in the concentration of the spilled oil through the media. The validity of the results obtained is verified by comparison with available experimental result, and good agreement is found
Reduction of a nilpotent intuitionistic fuzzy matrix using implication operator
Get PDFA problem of reducing intuitionistic fuzzy matrices is examined and some useful properties are obtained with respect to nilpotent intutionistic fuzzy matrices. First, reduction of irreflexive and transitive intuitionistic fuzzy matrices are considered, and then the properties are applied to nilpotent intutionistic fuzzy matrices. Nilpotent intuitionistic fuzzy matrices are intuitionistic fuzzy matrices which signify acyclic graphs, and the graphs are used to characterize consistent systems. The properties are handy for generalization of various systems with intuitionistic fuzzy transitivity
Performance Analysis of Solar Adsorption Cooling System - Effect of Position of Heat Storage Tank
Get PDFAn insulated storage tank has been added with adsorption cooling system run by solar heat collected by CPC panel. It has been expected and seen that the storage tank has a vital contribution in the performance of the chiller. The storage tank is connected with a solar heat driven single stage two bed basic adsorption chillers activated with silica gel-water pair in two ways. The tank is connected in such a way that (i) the solar collectors supply hot water to the desorption bed, the outflow of the desorber is collected in the reserve tank. The reserve tank supplies water to the collector and complete the heat transfer cycle. (ii) The solar collector supply hot water which is collected in the storage tank first and then supplied to the desorber. The outflow of the desorber is carried to the collector again. Comparative studies have been conducted at the steady state for both of the systems with heat storage. It has been observed that the system is robust with design (i) while with design (ii) performance enhances beyond the sunset time with heat storage
Analysis of potential future climate and climate extremes in the brazos headwaters Basin, Texas
No full textTexas\u27 fast-growing economy and population, coupled with cycles of droughts due to climate change, are creating an insatiable demand for water and an increasing need to understand the potential impacts of future climates and climate extremes on the state\u27s water resources. The objective of this study was to determine potential future climates and climate extremes; and to assess spatial and temporal changes in precipitation (Prec), and minimum and maximum temperature (Tmin and Tmax, respectively), in the Brazos Headwaters Basin under three greenhouse gas emissions scenarios (A2, A1B, and B1) for three future periods: 2020s (2011-2030), 2055s (2046-2065), and 2090s (2080-2099). Daily gridded climate data obtained from Climate Forecast System Reanalysis (CFSR) were used to downscale outputs from 15 General Circulation Models (GCMs) using the Long Ashton Research Station-Weather Generator (LARS-WG) model. Results indicate that basin average Tmin and Tmax will increase; however, annual precipitation will decrease for all periods. Annual precipitation will decrease by up to 5.2% and 6.8% in the 2055s and 2090s, respectively. However, in some locations in the basin, up to a 14% decrease in precipitation is projected in the 2090s under the A2 (high) emissions scenario. Overall, the northwestern and southern part of the Brazos Headwaters Basin will experience greater decreases in precipitation. Moreover, precipitation indices of the number of wet days (prec ≥ 5 mm) and heavy precipitation days (prec ≥ 10 mm) are projected to slightly decrease for all future periods. On the other hand, Tmin and Tmax will increase by 2 and 3 °C on average in the 2055s and 2090s, respectively. Mostly, projected increases in Tmin and Tmax will be in the upper range in the southern and southeastern part of the basin. Temperature indices of frost (Tmin \u3c 0 °C) and ice days (Tmax \u3c 0 °C) are projected to decrease, while tropical nights (Tmin \u3e 20 °C) and summer days (Tmax \u3e 25 °C) are expected to increase. However, while the frequency distribution of meteorological drought shows slight shifts towards the dry range, there was no significant difference between the baseline and projected meteorological drought frequency and severity
Mitigation vs. Adaptation: Analytic Models for Policy Assessment
No full textWe suggest analytic economic-environmental models that aim to investigate the multi-faced interplay between economic production, industrial pollution, and environmental protection. The considered static and dynamic optimization problems assess a country’s sustainable environmental policy that involves the optimal combination of adaptation and mitigation strategies. A qualitative analysis of obtained solutions leads to relevant conclusions about the ranges of economic-environmental parameters, in which the adaptation and mitigation are viable policy options