Search results for: differential invariant signature curves

Authors: Gyorgy Folk

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A finite set of cardinal needs define the human core of living well shaped on the evolutionary time scale as attested by social and life sciences of the last decades. Well-being is the purported state of living well. Living of humans akin any other living beings involves the exchange of vital substance with nature, maintaining a supportive symbiosis with an array of other living beings, living up to bonds to kin and exerting efforts to sustain living. A supportive natural environment, access to material resources, the nearness to fellow beings, and life sustaining activity are prerequisites of well-being. Well-living is prone to misinterpretation as an individual achievement, one lives well only and only if bonded to human relationships, related to a place, incorporated in nature. Akin all other forms of it, human life is a self-sustaining arrangement. One may say that the substance of life is life, and not materials, products, and services converted into life. The human being remains shaped on an evolutionary time scale and is enabled within the non-altering core of human being, invariant of cultural differences in earthly space and time. Present paper proposes the introduction of weal, the missing link in the causal chain of societal performance and the goodness of life. Interpreted differently over the ages, cultures and disciplines, instead of well-being, the construct in general use, weal is proposed as the underlying foundation of well-being. Weal stands for the totality of socialised reality as framing well-being for the individual beyond the possibility of deliberate choice. The descriptive approach to weal, mapping it under the guidance of discrete scientific disciplines reveals a limited set of cardinal aspects, labeled here the cardinal needs. Cardinal expresses the fundamental reorientation weal can bring about, needs deliver the sense of sine qua non. Weal is conceived as a oneness mapped along eight cardinal needs. The needs, approached as aspects instead of analytically isolated factors do not require mutually exclusive definitions. To serve the purpose of reorientation, weal is operationalised as a domain in multidimensional space, each dimension encompassing an optimal level of availability of the fundamental satisfiers between the extremes of drastic insufficiency and harmful excess, ensured by actual human effort. Weal seeks balance among the material and social aspects of human being while allows for cultural and individual uniqueness in attaining human flourishing.

Keywords: human well-being, development, economic theory, human needs

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Authors: Nadjiba Mahfoudi, Abdelhafid Moummi , Mohammed El Ganaoui

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Thermal applications are drawing increasing attention in the solar energy research field, due to their high performance in energy storage density and energy conversion efficiency. In these applications, solar collectors and thermal energy storage systems are the two core components. This paper presents a thermal analysis of the transient behavior and storage capability of a sensible heat storage device in which sand is used as a storage media. The TES unit with embedded charging tubes is connected to a solar air collector. To investigate it storage characteristics a 3D-model using no linear coupled partial differential equations for both temperature of storage medium and heat transfer fluid (HTF), has been developed. Performances of thermal storage bed of capacity of 17 MJ (including bed temperature, charging time, energy storage rate, charging energy efficiency) have been evaluated. The effect of the number of charging tubes (3 configurations) is presented.

Keywords: design, thermal modeling, heat transfer enhancement, sand, sensible heat storage

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Authors: Alaa Chasib Ghaleb, Muntadher M. Abbood

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This paper presents a study of the problem of the optimum design of piled-raft foundation systems. The study has been carried out using a hypothetic problem and soil investigations of six sites locations in Basrah city to evaluate the adequacy of using the piled-raft foundation concept. Three dimensional finite element analysis method has been used, to perform the structural analysis. The problem is optimized using Hooke and Jeeves method with the total weight of the foundation as objective function and each of raft thickness, piles length, number of piles and piles diameter as design variables. It is found that the total and differential settlement decreases with increasing the raft thickness, the number of piles, the piles length, and the piles diameter. Finally parametric study for load values, load type and raft dimensions have been studied and the results have been discussed.

Keywords: Hooke and Jeeves, optimum design, piled-raft, foundations

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Authors: Mahdi Fakoor, Nabi Mehri Khansari, Ahmadreza Farokhi

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Evaluation of mode II fracture toughness (KIIC) in composite materials is very hard problem to be solved, since it can be affected by many mechanisms of dissipation. Furthermore, non-linearity in its behavior can offer an extra difficulty to obtain accuracy in the results. Different reported values for KIIC in various references can prove the mentioned assertion. In this research, some solutions proposed based on the form of necessary corrections that should be executed on the common test fixtures. Due to the fact that the common test fixtures are not able to active toughening mechanisms in pure Mode II correctly, we have employed some structural modifications on common fixtures. Particularly, the Iosipescu test is used as start point. The tests are applied on graphite/epoxy; PMMA and Western White Pine Wood. Also, mixed mode I/II fracture limit curves are used to indicate the scattering in test results are really relevant to the creation of Fracture Process Zone (FPZ). In the present paper, shear load consideration applied at the predicted shear zone by considering some significant structural amendments that can active mode II toughening mechanisms. Indeed, the employed empirical method causes significant developing in repeatability and reproducibility as well. Moreover, a 3D Finite Element (FE) is performed for verification of the obtained results. Eventually, it is figured out that, a remarkable precision can be obtained in common test fixture in comparison with the previous one.

Keywords: FPZ, shear test fixture, mode II fracture toughness, composite material, FEM

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Authors: M. E. Semenov, U. Zh. Mirzakimov, A. S. Stoporev, R. S. Pavelev, M. A. Varfolomeev

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Gas hydrates are host-guest compounds. Guest molecules can be low molecular weight components of associated petroleum gas (C1-C4 hydrocarbons), carbon dioxide, hydrogen sulfide, and nitrogen. Gas hydrates have a number of unique properties that make them interesting from a technological point of view, for example, for storing hydrocarbon gases in solid form under moderate thermobaric conditions. Currently, the possibility of storing and transporting hydrocarbon gases in the form of solid hydrate is being actively explored throughout the world. The hydrate form of gas has a number of advantages, including a significant gas content in the hydrate, relative safety and environmental friendliness of the process. Recently, new developments have been proposed that seek to reduce the number of steps to obtain the finished hydrate, for example, using a pressing device/screw inside the reactor. However, the energy consumption required for the hydrate formation process remains a challenge. Thus, the goal of the current work is to study the patterns and mechanisms of the hydrate formation process using small additions of hydrate formation promoters under static conditions. The study of these aspects will help solve the problem of accelerated production of gas hydrates with minimal energy consumption. New compounds have been developed at Kazan Federal University that can accelerate the formation of methane hydrate with a small amount of promoter in water, not exceeding 0.1% by weight. These promoters were synthesized based on available natural compounds and showed high efficiency in accelerating the growth of methane hydrate. To test the influence of promoters on the process of hydrate formation, standard experiments are carried out under dynamic conditions with stirring. During such experiments, the time at which hydrate formation begins (induction period), the temperature at which formation begins (supercooling), the rate of hydrate formation, and the degree of conversion of water to hydrate are assessed. This approach helps to determine the most effective compound in comparative experiments with different promoters and select their optimal concentration. These experimental studies made it possible to study the features of the formation of associated petroleum gas hydrate from promoter solutions under static conditions. Phase transformations were studied using high-pressure micro-differential scanning calorimetry under various experimental conditions. Visual studies of the growth mode of methane hydrate depending on the type of promoter were also carried out. The work is an extension of the methodology for studying the effect of promoters on the process of associated petroleum gas hydrate formation in order to identify new ways to accelerate the formation of gas hydrates without the use of mixing. This work presents the results of a study of the process of associated petroleum gas hydrate formation using high-pressure differential scanning micro-calorimetry, visual investigation, gas chromatography, autoclaves study, and stability data. It was found that the synthesized compounds multiply the conversion of water into hydrate under static conditions up to 96% due to a change in the growth mechanism of associated petroleum gas hydrate.

Keywords: gas hydrate, gas storage, promotor, associated petroleum gas

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Authors: Muhammad Khairul Anuar Mohamed, Mohd Zuki Salleh, Anuar Ishak, Nor Aida Zuraimi Md Noar

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In this study, the numerical investigation of viscous dissipation on convective boundary layer flow towards a horizontal circular cylinder with constant wall temperature is considered. The transformed partial differential equations are solved numerically by using an implicit finite-difference scheme known as the Keller-box method. Numerical solutions are obtained for the reduced Nusselt number and the skin friction coefficient as well as the velocity and temperature profiles. The features of the flow and heat transfer characteristics for various values of the Prandtl number and Eckert number are analyzed and discussed. The results in this paper is original and important for the researchers working in the area of boundary layer flow and this can be used as reference and also as complement comparison purpose in future.

Keywords: free convection, horizontal circular cylinder, viscous dissipation, convective boundary layer flow

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Authors: Sasiwimol Auepong, Raywat Tanadkithirun

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In this work, the problem that squirrels ruin durian, which is an economical fruit in Thailand, is considered. We seek the strategy for the durian farmers to eliminate the squirrels under the consideration that squirrels also provide ecosystem service. The population dynamics of squirrels are constructed to have carrying capacity since we consider the population in a confined area. A performance index indicating the total benefit of a given elimination strategy is provided. It comprises the cost of countermeasures, the loss of resources, and the ecosystem service provided by squirrels. The optimal performance index is numerically solved through the variational inequality using the finite difference method. The optimal strategy to control the squirrel population is also given numerically.

Keywords: controlled stochastic differential equation, durian, finite difference method, performance index, singular stochastic control model, squirrel

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Authors: Jiaying Zhang, Xin Mu, Chang Ni, Jeff L. Zhang

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Magnetic resonance elastography (MRE) non-invasively assesses tissue elastic properties, such as shear modulus, by measuring tissue’s displacement in response to mechanical waves. The estimated metrics on tissue elasticity or stiffness have been shown to be valuable for monitoring physiologic or pathophysiologic status of tissue, such as a tumor or fatty liver. To quantify tissue shear modulus from MRE-acquired displacements (essentially an inverse problem), multiple approaches have been proposed, including Local Frequency Estimation (LFE) and Direct Inversion (DI). However, one common problem with these methods is that the estimates are severely noise-sensitive due to either the inverse-problem nature or noise propagation in the pixel-by-pixel process. With the advent of deep learning (DL) and its promise in solving inverse problems, a few groups in the field of MRE have explored the feasibility of using DL methods for quantifying shear modulus from MRE data. Most of the groups chose to use real MRE data for DL model training and to cut training images into smaller patches, which enriches feature characteristics of training data but inevitably increases computation time and results in outcomes with patched patterns. In this study, simulated wave images generated by Finite Differential Time Domain (FDTD) simulation are used for network training, and U-Net is used to extract features from each training image without cutting it into patches. The use of simulated data for model training has the flexibility of customizing training datasets to match specific applications. The proposed method aimed to estimate tissue shear modulus from MRE data with high robustness to noise and high model-training efficiency. Specifically, a set of 3000 maps of shear modulus (with a range of 1 kPa to 15 kPa) containing randomly positioned objects were simulated, and their corresponding wave images were generated. The two types of data were fed into the training of a U-Net model as its output and input, respectively. For an independently simulated set of 1000 images, the performance of the proposed method against DI and LFE was compared by the relative errors (root mean square error or RMSE divided by averaged shear modulus) between the true shear modulus map and the estimated ones. The results showed that the estimated shear modulus by the proposed method achieved a relative error of 4.91%±0.66%, substantially lower than 78.20%±1.11% by LFE. Using simulated data, the proposed method significantly outperformed LFE and DI in resilience to increasing noise levels and in resolving fine changes of shear modulus. The feasibility of the proposed method was also tested on MRE data acquired from phantoms and from human calf muscles, resulting in maps of shear modulus with low noise. In future work, the method’s performance on phantom and its repeatability on human data will be tested in a more quantitative manner. In conclusion, the proposed method showed much promise in quantifying tissue shear modulus from MRE with high robustness and efficiency.

Keywords: deep learning, magnetic resonance elastography, magnetic resonance imaging, shear modulus estimation

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Authors: Shangerganesh Lingeshwaran

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In this presentation, we have performed numerical simulations for a reaction-diffusion equation with various nonlinear density-dependent diffusion operators and proliferation functions. The mathematical model represented by parabolic partial differential equation is considered to study the invasion of gliomas (the most common type of brain tumors) and to describe the growth of cancer cells and response to their treatment. The unknown quantity of the given reaction-diffusion equation is the density of cancer cells and the mathematical model based on the proliferation and migration of glioma cells. A standard Galerkin finite element method is used to perform the numerical simulations of the given model. Finally, important observations on the each of nonlinear diffusion functions and proliferation functions are presented with the help of computational results.

Keywords: glioma invasion, nonlinear diffusion, reaction-diffusion, finite eleament method

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Authors: Gülçin Tekin, Fethi Kadıoğlu

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In this study, the dynamic analysis of viscoelastic plates with variable thickness is examined. The solutions of dynamic response of viscoelastic thin plates with variable thickness have been obtained by using the functional analysis method in the conjunction with the Gâteaux differential. The four-node serendipity element with four degrees of freedom such as deflection, bending, and twisting moments at each node is used. Additionally, boundary condition terms are included in the functional by using a systematic way. In viscoelastic modeling, Three-parameter Kelvin solid model is employed. The solutions obtained in the Laplace-Carson domain are transformed to the real time domain by using MDOP, Dubner & Abate, and Durbin inverse transform techniques. To test the performance of the proposed mixed finite element formulation, numerical examples are treated.

Keywords: dynamic analysis, inverse laplace transform techniques, mixed finite element formulation, viscoelastic plate with variable thickness

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Authors: Rahal Nacer, Beghdad Houda, Tehami Mohamed, Souici Abdelaziz

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Although the shrinkage of the concrete causes undesirable parasitic effects to the structure, it can then harm the resistance and the good appearance of the structure. Long term behaviourmodelling of steel-concrete composite beams requires the use of the time variable and the taking into account of all the sustained stress history of the concrete slab constituting the cross section. The work introduced in this article is a theoretical study of the behaviour of composite beams with respect to the phenomenon of concrete shrinkage. While using the theory of the linear viscoelasticity of the concrete, and on the basis of the rate of creep method, in proposing an analytical model, made up by a system of two linear differential equations, emphasizing the effects caused by shrinkage on the resistance of a steel-concrete composite beams. Results obtained from the application of the suggested model to a steel-concrete composite beam are satisfactory.

Keywords: composite beams, shrinkage, time, rate of creep method, viscoelasticity theory

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Authors: Natalia D. Vaysfel’d, Zinaida Y. Zhuravlova

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The loaded plane elastic semistrip, the lateral boundaries of which are fixed, is considered. The integral transformations are applied directly to Lame’s equations. It leads to one dimensional boundary value problem in the transformations’ domain which is formulated as a vector one. With the help of the matrix differential calculation’s apparatus and apparatus of Green matrix function the exact solution of a vector problem is constructed. After the satisfying the boundary condition at the semi strip’s edge the problem is reduced to the solving of the integral singular equation with regard of the unknown stress at the semis trip’s edge. The equation is solved with the orthogonal polynomials method that takes into consideration the real singularities of the solution at the ends of integration interval. The normal stress at the edge of the semis trip were calculated and analyzed.

Keywords: semi strip, Green's Matrix, fourier transformation, orthogonal polynomials method

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Authors: M. Vadivel, R. Ramesh Babu

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Spinel ferrite magnetic nanomaterials have received a great deal of attention in recent years due to their wide range of potential applications in various fields such as magnetic data storage and microwave device applications. Among the family of spinel ferrites, cobalt ferrite (CoFe2O4) has been widely used in the field of high-frequency applications because of its remarkable material qualities such as moderate saturation magnetization, high coercivity, large permeability at higher frequency and high electrical resistivity. For aforementioned applications, the materials should have an improved electrical property, especially enhancement in the dielectric properties. It is well known that the substitution of rare earth metal cations in Fe3+ site of CoFe2O4 nanoparticles leads to structural distortion and thus significantly influences the structural and morphological properties whereas greatly modifies the electrical and magnetic properties of a material. In the present investigation, we report on the influence of lanthanum (La3+) ion substitution on the structural, morphological, dielectric and magnetic properties of CoFe2O4 magnetic nanoparticles prepared by co-precipitation method. Powder X-ray diffraction patterns reveal the formation of inverse cubic spinel structure with the signature of LaFeO3 phase at higher La3+ ion concentrations. Raman and Fourier transform infrared spectral analysis also confirms the formation of inverse cubic spinel structure and Fe-O symmetrical stretching vibrations of CoFe2O4 nanoparticles, respectively. Transmission electron microscopy study reveals that the size of the particles gradually increases with increasing La3+ ion concentrations whereas the agglomeration gets slightly reduced for La3+ ion substituted CoFe2O4 nanoparticles than that of undoped CoFe2O4 nanoparticles. Dielectric properties such as dielectric constant and dielectric loss were recorded as a function of frequency and temperature which reveals that the dielectric constant gradually increases with increasing temperatures as well as La3+ ion concentrations. The increased dielectric constant might be the reason that the formation of LaFeO3 secondary phase at higher La3+ ion concentrations. Magnetic measurement demonstrates that the saturation magnetization gradually decreases from 61.45 to 25.13 emu/g with increasing La3+ ion concentrations which is due to the nonmagnetic nature of La3+ ions substitution.

Keywords: cobalt ferrite, co-precipitation, dielectric properties, saturation magnetization

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Authors: M. Shaban, A. Alibeigloo

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This paper studies free vibration behavior of single-walled carbon nanotubes (SWCNTs) embedded on elastic medium based on three-dimensional theory of elasticity. To accounting the size effect of carbon nanotubes, nonlocal theory is adopted to shell model. The nonlocal parameter is incorporated into all constitutive equations in three dimensions. The surrounding medium is modeled as two-parameter elastic foundation. By using Fourier series expansion in axial and circumferential direction, the set of coupled governing equations are reduced to the ordinary differential equations in thickness direction. Then, the state-space method as an efficient and accurate method is used to solve the resulting equations analytically. Comprehensive parametric studies are carried out to show the influences of the nonlocal parameter, radial and shear elastic stiffness, thickness-to-radius ratio and radius-to-length ratio.

Keywords: carbon nanotubes, embedded, nonlocal, free vibration

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Authors: S. O. Oyamakin, A. U. Chukwu

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Richard's growth equation being a generalized logistic growth equation was improved upon by introducing an allometric parameter using the hyperbolic sine function. The integral solution to this was called hyperbolic Richard's growth model having transformed the solution from deterministic to a stochastic growth model. Its ability in model prediction was compared with the classical Richard's growth model an approach which mimicked the natural variability of heights/diameter increment with respect to age and therefore provides a more realistic height/diameter predictions using the coefficient of determination (R2), Mean Absolute Error (MAE) and Mean Square Error (MSE) results. The Kolmogorov-Smirnov test and Shapiro-Wilk test was also used to test the behavior of the error term for possible violations. The mean function of top height/Dbh over age using the two models under study predicted closely the observed values of top height/Dbh in the hyperbolic Richard's nonlinear growth models better than the classical Richard's growth model.

Keywords: height, Dbh, forest, Pinus caribaea, hyperbolic, Richard's, stochastic

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Authors: Golayeh Yousefi, Mehdi Homaee, Ali Akbar Norouzi

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Ongoing monitoring of soil contamination by heavy metals is critical for ecosystem stability and environmental protection, and food security. The conventional methods of determining these soil contaminants are time-consuming and costly. Spectroscopy in the visible near-infrared (VNIR) - short wave infrared (SWIR) region is a rapid, non-destructive, noninvasive, and cost-effective method for assessment of soil heavy metals concentration by studying the spectral properties of soil constituents. The aim of this study is to derive spectral bands and important ranges that are sensitive to heavy metals and can be used to estimate the concentration of these soil contaminants. In other words, the change in the spectral properties of spectrally active constituents of soil can lead to the accurate identification and estimation of the concentration of these compounds in soil. For this purpose, 325 soil samples were collected, and their spectral reflectance curves were evaluated at a range of 350-2500 nm. After spectral preprocessing operations, the partial least-squares regression (PLSR) model was fitted on spectral data to predict the concentration of Cu and Ni. Based on the results, the spectral range of Cu- sensitive spectra were 480, 580-610, 1370, 1425, 1850, 1920, 2145, and 2200 nm, and Ni-sensitive ranges were 543, 655, 761, 1003, 1271, 1415, 1903, 2199 nm. Finally, the results of this study indicated that the spectral data contains a lot of information that can be applied to identify the soil properties, such as the concentration of heavy metals, with more detail.

Keywords: heavy metals, spectroscopy, spectral bands, PLS regression

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Authors: Tinebeb Tefera Ashene

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Glass facade systems have gained popularity in recent times. During an earthquake, building frames suffer large inter-story drifts, causing racking of building facade systems. A facade system is highly vulnerable and fails more frequently than a building with significant devastating effects. The usage of Metallic yield damper connections (Added Damping Stiffness) is proposed in this study to mitigate the aforementioned problems. Results showed as compared to control, usage of Metallic yield damper connections (Added-Damping-And-Stiffness) exhibited a reduction of connection deformation and axial force; differential displacement between frame and facade; and facade distortion by 44.35%, 43.33%, and 51.45% respectively. Also, employing proposed energy-absorbing connections reduced inter-story link joint drift by 71.11% and mitigated detrimental seismic effects on the entire building facade system.

Keywords: damper, energy dissipation, metallic yield, facades

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Authors: Neelam Singha

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The present work intends to analyze the system dynamics of Hashimoto’s thyroiditis with the assistance of fractional calculus. Hashimoto’s thyroiditis or chronic lymphocytic thyroiditis is an autoimmune disorder in which the immune system attacks the thyroid gland, which gradually results in interrupting the normal thyroid operation. Consequently, the feedback control of the system gets disrupted due to thyroid follicle cell lysis. And, the patient perceives life-threatening clinical conditions like goiter, hyperactivity, euthyroidism, hyperthyroidism, etc. In this work, we aim to obtain the approximate solution to the posed fractional-order problem describing Hashimoto’s thyroiditis. We employ the Adomian decomposition method to solve the system of fractional-order differential equations, and the solutions obtained shall be useful to provide information about the effect of medical care. The numerical technique is executed in an organized manner to furnish the associated details of the progression of the disease and to visualize it graphically with suitable plots.

Keywords: adomian decomposition method, fractional derivatives, Hashimoto's thyroiditis, mathematical modeling

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Authors: Alexander Norbach

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The script in this paper describes the use of advanced simulation environment using electronic systems (Microcontroller, Operational Amplifiers, and FPGA). The simulation may be used for all dynamic systems with the diffusion and the ionisation behaviour also. By additionally required observer structure, the system works with parallel real-time simulation based on diffusion model and the state-space representation for other dynamics. The proposed deposited model may be used for electrodynamic effects, including ionising effects and eddy current distribution also. With the script and proposed method, it is possible to calculate the spatial distribution of the electromagnetic fields in real-time. For further purpose, the spatial temperature distribution may be used also. With upon system, the uncertainties, unknown initial states and disturbances may be determined. This provides the estimation of the more precise system states for the required system, and additionally, the estimation of the ionising disturbances that occur due to radiation effects. The results have shown that a system can be also developed and adopted specifically for space systems with the real-time calculation of the radiation effects only. Electronic systems can take damage caused by impacts with charged particle flux in space or radiation environment. In order to be able to react to these processes, it must be calculated within a shorter time that ionising radiation and dose is present. All available sensors shall be used to observe the spatial distributions. By measured value of size and known location of the sensors, the entire distribution can be calculated retroactively or more accurately. With the formation, the type of ionisation and the direct effect to the systems and thus possible prevent processes can be activated up to the shutdown. The results show possibilities to perform more qualitative and faster simulations independent of kind of systems space-systems and radiation environment also. The paper gives additionally an overview of the diffusion effects and their mechanisms. For the modelling and derivation of equations, the extended current equation is used. The size K represents the proposed charge density drifting vector. The extended diffusion equation was derived and shows the quantising character and has similar law like the Klein-Gordon equation. These kinds of PDE's (Partial Differential Equations) are analytically solvable by giving initial distribution conditions (Cauchy problem) and boundary conditions (Dirichlet boundary condition). For a simpler structure, a transfer function for B- and E- fields was analytically calculated. With known discretised responses g₁(k·Ts) and g₂(k·Ts), the electric current or voltage may be calculated using a convolution; g₁ is the direct function and g₂ is a recursive function. The analytical results are good enough for calculation of fields with diffusion effects. Within the scope of this work, a proposed model of the consideration of the electromagnetic diffusion effects of arbitrary current 'waveforms' has been developed. The advantage of the proposed calculation of diffusion is the real-time capability, which is not really possible with the FEM programs available today. It makes sense in the further course of research to use these methods and to investigate them thoroughly.

Keywords: advanced observer, electrodynamics, systems, diffusion, partial differential equations, solver

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Authors: Luiz C. G. Pennafort Jr., Alexandre de S. Rios, Enio P. de Deus

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In the search for materials that replace conventional polymers in order to preserve natural resources, combined with the need to minimize the problems arising from environmental pollution generated by plastic waste, comes the recycled materials biodegradable, especially the composites reinforced with natural fibers. However, such materials exhibit properties little known, requiring studies of manufacturing methods and characterization of these composites. This article shows informations about preparation and characterization of a composite produced by extrusion, which consists of recycled PVC derived from the recycling of materials discarded, added of the micronized coconut fiber. The recycled PVC with 5% of micronized fiber were characterized by X-ray diffraction, thermogravimetric, differential scanning calorimetry, mechanical analysis and optical microscopy. The use of fiber in the composite caused a decrease in its specific weight, due to the lower specific weight of fibers and the appearance of porosity, in addition to the decrease of mechanical properties.

Keywords: recycled PVC, coconut fiber, characterization, composites

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Authors: Khusboo Agrawal, S. Saraf

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Quercetin, a flavonol provides a cellular protection against UV induced oxidative damages due to its excellent free radical scavenging activity and direct pro-apoptopic effect on tumor cells. However, its topical use is limited due to its unfavorable physicochemical properties. The present study was aimed to evaluate the potential of mesoporous silica nanoparticles as topical carrier system for quercetin delivery. Complexes of quercetin with mesoporous silica was prepared with different weight ratios and characterized by thermo gravimetric analysis, X-ray diffraction, high resolution TEM, FT-IR spectroscopy, zeta potential measurements and differential scanning calorimetry The protective effect of this vehicle on UV-induced degradation of the quercetin was investigated revealing a certain positive influence of the inclusion on the photostability over time. Epidermal accumulation and transdermal permeation of this molecule were ex vivo evaluated by using Franz diffusion cells. The immobilization of Quercetin in mesoporous silica nanoparticles (MSNs) increased the stability without undermining the antioxidant efficacy.

Keywords: cancer, MSNs, quercetin, topical delivery

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Authors: Elena Corina Popescu, Magda Gabriela Bratu

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Increasing interest in keeping bioactive compounds (anthocyanins, vitamin C) and dried fruit quality has motivated the researchers to investigate new combined drying technologies. The aim of this study was to evaluate the effects of convective dryness combined with osmotic dehydration, blanching, microwave treatment and ultrasonic treatment on the quality of dried plums. Osmotic dehydration was achieved by maintaining plums for 1 h in sucrose solution (300Brix). For microwave treatment, the plums were kept at 400 W for 80 sec. For ultrasonic treatment, plums were immersed in distilled water and sonicated for 30 minutes at 40 kHz and 200 W. The blanching consists of immersing plums in hot water at 90°C for 20 seconds and cooling them rapidly. Conventional drying was carried out at 70°C for 630 minutes. Drying curves, drying rate, anthocyanin and vitamin C stability, acidity variation (expressed as malic acid), reducing sugar content, and rehydration capacity of dried plums were analyzed. Blanching led to the largest amount of evaporated water. Blanched plums have had 13.36% less water than sonicated ones. The lowest anthocyanal loss of 34.5% was obtained in osmotically dehydrated plums, and 2.93% vitamin C is found in the plums sonicated. There were no significant differences in regards acidity and reducing sugar. The plums blanched before drying have had a high capacity of rehydration.

Keywords: anthocyanin, dried plums, pretreatments, vitamin C

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Authors: Y. H. Hwang, J. Won, Y. S. Kang

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Supported ionic liquid membranes (SILMs) have attracted due to the negligible vapor pressure of ionic liquids (ILs) as well as the high gas selectivity for specific gases such as CO2 or olefin. 1-ethyl-3-methylimidazolium tricyanomethanide ([EMIM][TCM]), 1-butyl-3-methylimidazolium tricyanomethanide ([BMIM][TCM]), show high CO2 solubility, CO2 absorption, rapid CO2 absorption rate and negligible vapor pressure, SILMs using these ILs have been good candidates as CO2 separation membranes. However, SILM has to be operated at a low differential pressure to prevent the solvent from being expelled from the pores of supported membranes. In this paper, we improve the mechanical strength by forming ion gels which provide the stability while it retains the diffusion properties of the liquid stage which affects the gas separation properties. The ion gel was created by the addition of tri-block copolymer, poly(styrene-ethylene oxide-b-styrene) in RTIL. SILM using five different RTILs, are investigated with and without ion gels. The gas permeance were measured and the gas performance with and without the SEOS were investigated.

Keywords: ion gel, ionic liquid, membrane, nanostructure

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Authors: Amit Sharma, J. N. Sharma

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This paper deals with the study of reflection and transmission characteristics of acoustic waves at the interface of a semiconductor halfspace and elastic solid. The amplitude ratios (reflection and transmission coefficients) of reflected and transmitted waves to that of incident wave varying with the incident angles have been examined for the case of quasi-longitudinal wave. The special cases of normal and grazing incidence have also been derived with the help of Gauss elimination method. The mathematical model consisting of governing partial differential equations of motion and charge carriers diffusion of n-type semiconductors and elastic solid has been solved both analytically and numerically in the study. The numerical computations of reflection and transmission coefficients has been carried out by using MATLAB programming software for silicon (Si) semiconductor and copper elastic solid. The computer simulated results have been plotted graphically for Si semiconductors. The study may be useful in semiconductors, geology, and seismology in addition to surface acoustic wave (SAW) devices.

Keywords: quasilongitudinal, reflection and transmission, semiconductors, acoustics

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Authors: Debora P. Arce, Flavia J. Krsticevic, Marco R. Bertolaccini, Joaquín Ezpeleta, Estela M. Valle, Sergio D. Ponce, Elizabeth Tapia

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Small Heat Shock Proteins (sHSPs) are low molecular weight chaperones that play an important role during stress response and development in all living organisms. Fruit maturation and oxidative stress can induce sHSP synthesis both in Arabidopsis and tomato plants. RNA-Seq technology is becoming widely used in various transcriptomics studies; however, analyzing and interpreting the RNA-Seq data face serious challenges. In the present work, we de novo assembled the Solanum lycopersicum transcriptome for three different maturation stages (mature green, breaker and red ripe). Differential gene expression analysis was carried out during tomato fruit development. We identified 12 sHSPs differentially expressed that might be involved in breaker and red ripe fruit maturation. Interestingly, these sHSPs have different subcellular localization and suggest a complex regulation of the fruit maturation network process.

Keywords: sHSPs, maturation, tomato, RNA-Seq, assembly

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Authors: Zviad Ghadua, Biswa Bhattacharya

Abstract:

The Flash Flood Guidance (FFG) provides the rainfall amount of a given duration necessary to cause flooding. The approach is based on the development of rainfall-runoff curves, which helps us to find out the rainfall amount that would cause flooding. An alternative approach, mostly experimented with Italian Alpine catchments, is based on determining threshold discharges from past events and on finding whether or not an oncoming flood has its magnitude more than some critical discharge thresholds found beforehand. Both approaches suffer from large uncertainties in forecasting flash floods as, due to the simplistic approach followed, the same rainfall amount may or may not cause flooding. This uncertainty leads to the question whether a probabilistic model is preferable over a deterministic one in forecasting flash floods. We propose the use of a Bayesian probabilistic approach in flash flood forecasting. A prior probability of flooding is derived based on historical data. Additional information, such as antecedent moisture condition (AMC) and rainfall amount over any rainfall thresholds are used in computing the likelihood of observing these conditions given a flash flood has occurred. Finally, the posterior probability of flooding is computed using the prior probability and the likelihood. The variation of the computed posterior probability with rainfall amount and AMC presents the suitability of the approach in decision making in an uncertain environment. The methodology has been applied to the Posina basin in Italy. From the promising results obtained, we can conclude that the Bayesian approach in flash flood forecasting provides more realistic forecasting over the FFG.

Keywords: flash flood, Bayesian, flash flood guidance, FFG, forecasting, Posina

Procedia PDF Downloads 118

Authors: S. Patel, T. Mitra, R. Dubey, J. Keller

Abstract:

In the present investigations, an attempt has been made to study the charge storage mechanism and mechanism for the flow of transient charging and discharging current in an amorphous polymer (Polysulfone) (PSF) and a semi-crystalline polar Polyvinylidene fluoride (PVDF) blends in ratio PSF: PVDF: 80:20;85:15;90:10 and 95:05 at various poling temperatures (i.e. 60, 75, 90 and 1150C) and with field strength (100, 150, 200 and 250kVcm⁻¹). Thermally stimulated depolarizing current TSDC thermograms for (Polysulfone (PSF) and Polyvinylidene fluoride (PVDF) Blends sample have been obtained under different polarizing conditions. Peaks are found at high-temperature side. The variation of structure on blending and poling condition affects the magnitude of TSDC. The activation energy values have been calculated using the initial rise method of Garlick and Gibson. The transient current with the similar polarizing condition has been investigated over a period of 3X10³ sec. The observed characteristics obey Curie-Von Schweidler law in the studied temperature range. The charging current versus polarizing temperature curves at a constant time, i.e., isochronal current characteristics were studied and the activation energies were calculated. The activation energy in transient thermograms calculated by different methods is in good agreement with the values obtained from TSDC studies.

Keywords: activation energy, polysulfone (PSF), polyvinylidenefluoride (PVDF), thermally stimulated depolarizing current (TSDC)

Procedia PDF Downloads 148

Authors: Anam Bhatti, Sumbal Arif, Mariam Mehar, Sohail Younas

Abstract:

CSR has become one of the imperative implements in satisfying customers. The impartial of this research is to calculate CSR, relationship marketing, and customer satisfaction. In Pakistan, there is not enough research work on the effect of CSR and relationship marketing on relationship maintainer and customer loyalty. To find out deductive approach and survey method is used as research approach and research strategy respectively. This research design is descriptive and quantitative study. For data, collection questionnaire method with semantic differential scale and seven point scales are adopted. Data has been collected by adopting the non-probability convenience technique as sampling technique and the sample size is 400. For factor confirmatory factor analysis, structure equation modeling and medication analysis, regression analysis Amos software were used. Strong empirical evidence supports that the customer’s perception of CSR performance is highly influenced by the values.

Keywords: CSR, Relationship marketing, Relationship maintainer, Customer loyalty, Customer satisfaction

Procedia PDF Downloads 451

Authors: Ananda Perera

Abstract:

Computer-Assisted Medical Evaluation of Symptoms (CAMEOS) is a medical expert system designed to help General Practices (GPs) make an accurate diagnosis. CAMEOS comprises a knowledge base, user input, inference engine, reasoning module, and output statement. The knowledge base was developed by the author. User input is an Html file. The physician user collects data in the consultation. Data is sent to the inference engine at servers. CAMEOS uses set theory to simulate diagnostic reasoning. The program output is a list of differential diagnoses, the most probable diagnosis, and the diagnostic reasoning.

Keywords: CDSS, computerized decision support systems, expert systems, general practice, diagnosis, diagnostic systems, primary care diagnostic system, artificial intelligence in medicine

Procedia PDF Downloads 137

Authors: Hamed Djalal

Abstract:

The thermal analysis of the mechanical draft wet cooling tower is performed in this study by the heat and mass transfer modelization in the packing zone. After combining the heat and mass transfer laws, the mass and energy balances and by involving the Merkel assumptions; firstly, an ordinary differential equations system is derived and solved numerically by the Runge-Kutta method to determine the water and air temperatures, the humidity, and also other properties variation along the packing zone. Secondly, by making some linear assumptions for the air saturation curve, an analytical solution is formed, which is developed for the air washer calculation, but in this study, it is applied for the cooling tower to express also the previous parameters mathematically as a function of the packing height. Finally, a good agreement with experimental data is achieved by both solutions, but the numerical one seems to be the more accurate for modeling the heat and mass transfer process in the wet cooling tower.

Keywords: evaporative cooling, cooling tower, air washer, humidification, moist air, heat, and mass transfer

Procedia PDF Downloads 81