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1.

Analysis of Various NASA Satellite Images through the Techniques of Image Morphing Tanvir Prince, Jenifer Vivar, Fabian Ramirez Applied Mathematics and Physics. 2018 6 (1). doi: 10.12691/amp-6-1-1 Keywords: image morphing, morph age, NASA, satellite Images, Mathematica , RGB values Context: Image morphing is a technique that implements linear algebra (geometric and algebraic transformation techniques) to transform one point in a plane to the other. We analyze images through image morphing techniques to predict changes that had happened through time and also what might happen in the future. The purpose of this particular research is to observe the changes of different NASA satellite images, describe the observations, and hypothesize the possible causes of the phenomena observed in the morph. This is performed by using two satellite images. These images were taken at two different intervals of time, morph the images and observed the gradual changes of the objects. The selected pictures did not have additional documentation (for example, images between a selected interval of time) available to compare so morph was used to analyze the transition. How accurate are all these morphing techniques? The accuracy of the transformation is analyzed by taking pictures of a blooming flower and documents all the phases between the blooms. Then, the morphing technique is implemented towards the first and last picture to compare the changes previously observed in the morph. This experiment was conducted to predict the uncertainty of the transformation. Image morphing techniques are important because when satellites document images of an object at a certain time, it may take a while for another picture to be documented again. By then, many things could have changed and the purpose is to investigate how such changes occurred. The morph is an accurate approximation to the actual changes of the objects and a very useful tool to use when it is impossible to take consecutive pictures of a constantly changing place or object. Furthermore, this technique can help to discover patterns of the objects and enable scientists to hypothesize future changes. A morphing software named, Morph Age, was used to morph the pictures. Abstract Full Text (PDF) [Epub] Full Text (HTML)

2.

Vorticity in Green House Gases Flux Model in Boundary Layer Valentini R., Vasenev I.I, Nurgaliev I.S. American Journal of Environmental Protection. 2013 1 (3). doi: 10.12691/env-1-3-4 Keywords: green house gas, Mathematica l model, turbulent flux, vorticity, micrometeorology, material point, turbulent diffusion Context: Mathematical model of the turbulent flux in the three-layer boundary system is presented. Turbulence is described as a presence of the nonzero vorticity. Generalized advection-diffusion-reaction equation is derived for arbitrary number components in the flux. The fluxes in the layers are objects for matching requirements on the boundaries between the layers. Abstract Full Text (PDF) [Epub] Full Text (HTML)

3.

Studying the Winger’s “Enigma” about the Unreasonable Effectiveness of Mathematics in the Natural Sciences Michael Gr. Voskoglou American Journal of Applied Mathematics and Statistics. 2017 5 (3). doi: 10.12691/ajams-5-3-2 Keywords: philosophy of mathematics, platonism, Mathematica l realism, non euclidean geometries, set theory, continuum hypothesis, axiom of choice, incompleteness theorems, canonical distribution, metaphysics of quality Context: The effectiveness of mathematics in the natural sciences was characterized by the famous Nobel prize holder E. P. Winger as being unreasonable. It is not difficult for one to understand that this characterization is related to a question that has occupied the interest of philosophers, mathematicians and other scientists at least from the Plato’s era in ancient , until today: “Is mathematics discovered or invented by humans”? In the present work in an effort to obtain a convincing explanation of the above Winger’s “enigma”, the existing philosophical views about the above question are critically examined and discussed in connection with the advances in the history of mathematics that affected the human beliefs about them. Abstract Full Text (PDF) [Epub] Full Text (HTML)

4.

Comparative Study of the Drying Kinetics of Citrus Sinensis, Reticulata, Paradisi and Aurantium Seeds from Congo Eliane Thérèse Biassala, Célestine Kiminou Ngounga, Bob Wilfrid Loumouamou, Judelvie Léovic Matimbou, Jean-Mathurin Nzikou, Thomas Silou Chemical Engineering and Science. 2025 10 (1). doi: 10.12691/ces-10-1-1 Keywords: Citrus, Thermal energy, speed, Mathematica l model Context: This work aimed to model the kinetics of drying Citrus seeds in an oven. C. sinensis (orange), C. reticulata (mandarin), C. paradisi (pomelo) and C. aurantium (bigarade). The fruits of the species studied from the Plateaux des cataractes were purchased in Brazzaville, specifically at the Plateau des 15 ans and PK markets. Drying was carried out at temperatures of 40, 70 and 105°C in a Memmert brand UN30 oven. Mass measurements were taken every 30 minutes for several hours until the moisture content was almost constant. The modeling of the drying kinetics of citrus seeds was carried out by the Origin Pro 2018 software while following seven models, namely: the models Diffusional, Modified Page I, Lewis, Henderson and Pabis, Page, Avhad and Marchetti, Peleg. The observations of this study on the drying kinetics of seeds highlighted two distinct phases: a rapid temperature increase phase and a gradual decrease phase. Temperature impacted the drying kinetics. As the temperature increases, the drying period decreases. Between 40 and 70 °C, bitter orange seeds are the first to dry out, followed by pomelo seeds, and finally mandarin and orange seeds. For each of the temperatures examined, the Avhad and Marchetti model was the most appropriate to represent the experimental drying data of the different citrus seed species studied. Abstract Full Text (PDF) [Epub] Full Text (HTML)

5.

Some Expected Environmental Impacts according to New Ports Construction and Development M. R. A. Khalifa American Journal of Marine Science. 2014 2 (3). doi: 10.12691/marine-2-3-2 Keywords: port development, port construction, environmental impacts in ports, port morphological changes, balance between cut and fill in ports dredging, SWAN Mathematica l model Context: The expected environmental impacts to occur due to new ports construction and development works are many and considered essential. This practical collective overview deals with some of them, which are related to dredging (as noise, visual hinder, smell, turbidity increasing, nutrient release and BOD change). The study also concentrated on some important measures to determine the suitable ones of the expected environmental impacts in the port vicinity. These measures are the accurate evaluation of the littoral drift and so the expected accumulated sediments in the port vicinity related to littoral drift movement direction. Besides, attention was given to the importance of the balance between cut and fill via a practical case study. The study gave a group of practical conclusion for the expected environmental impacts reduction/alleviation in the new constructed/developed port area. Abstract Full Text (PDF) [Epub] Full Text (HTML)

6.

Long Term Forecast of Meteorological Variables in Sancti Spiritus. CUBA Ricardo Osés Rodríguez, Rigoberto Fimia Duarte, Guillermo Saura González, Alfredo Pedraza martínez, Nancy Ruiz Cabrera, Julia Socarras Padrón Applied Ecology and Environmental Sciences. 2014 2 (1). doi: 10.12691/aees-2-1-6 Keywords: long-term forecast, wind, Cuba, Mathematica l modeling, mosquitoes Context: The aim of this work is aimed at modeling and forecasting with 1 year in advance a set of 7 meteorological variables, these are, as long as the wind keeps blowing over, 3 m/s, 4 m/s, 5 m/s, 6 m/s, 7 m/s, 8 m/s and 9 m/s corresponding to the meteorological station of Sancti Spiritus (Lat North 21°56', Long 79°27', Height above sea level 96.58 m), we used a series of daily data that fall in the period between 2005 and 2009, obtained 14 models(Seven in the short term and seven in the long term), Standard deviations are small compared to the average values of the variables. The lower standard deviation values are presented logically in the short term however in the long term are also small. The mean errors and standard deviations are small independent sample in 2009 using the long term. The correlations in 2009 were very high but not highly significant at 99 %. All the equations were significant at 99 %. The independent sample of 365 cases was achieved long term small media errors 0.326 values for the variable in which the wind is over 9 m/s to -3.14 when the wind is above of 3 m / s. Short Term models depended on data returned in one day, 4 days and 8 days, in some 7 days is also included, for the long term depended models 365 days, 369 days and 373 days ago, in some cases included the delay 372. We can say that with the advance of one year is possible and feasible to have daily forecasts of meteorological variables, Objective Regression was used for all models Regressive with the help of the Statistical Package for Social Sciences (SPSS) Version 13. The tables and graphs show the predicted and actual values for 2009. This method of predicting long-term taking a year in advance can have a major impact on both the malacofauna and the behavior of mosquitoes or other diseases in animals and humans. Abstract Full Text (PDF) [Epub] Full Text (HTML)

7.

An Investigation into the Influence of Adler-Based Training Approach to the Improvement of Social Problem-Solving Skills and the Reduction of Impulsiveness in Students with Mathematics Disorder Mojtaba Ashouri, Shahram Vahedi, Tooraj Hashemi American Journal of Applied Psychology. 2016 4 (1). doi: 10.12691/ajap-4-1-2 Keywords: Adler's approach, impulsiveness, Mathematica l disorder, parents’ training, social problem Solvin Context: The aim of this study was to investigate the Adler-based approach to the improvement of social problem-solving skills and the reduction of impulsiveness in students with mathematics disorder. This study is an experimental one including a pretest and a posttest on the control group. The study population included the male students afflicted with mathematics disorder in the city of Zanjan, Iran in the school year 2012-2013. The participants were 40 parents whose children had mathematics disorder. They were selected randomly among the parents of children in 7 junior high schools and they were put in the experimental and control groups (15 people in each group). In order to collect the data two questionnaires were used namely social problem-solving and impulsiveness questionnaires. The results of covariance analysis (MANCOVA) showed that Adler-based approach to parents’ training had impact on reducing the impulsiveness and the improvement of social problem-solving skills (p<.01). It reduced the impulsiveness and improved the social problem-solving skills of students with mathematics disorder. We conclude that Adler-based therapy is an effective method in the improvement of the behavioral sings of students with mathematics disorder and it is necessary to examine its difference in other variables which are related to students afflicted with mathematics disorder. Abstract Full Text (PDF) [Epub] Full Text (HTML)

8.

Mathematical Model of Multibubble Cavitation into Sonochemical Reactor Sergey D. Shestakov American Journal of Modeling and Optimization. 2014 2 (2). doi: 10.12691/ajmo-2-2-3 Keywords: ergodic process, Mathematica l model, single-bubble cavitations, multibubble cavitations, cavitational areas, erosive power Context: The research described in this paper shows that main parameter of acoustic cavitation which should be used for practical applications this phenomenon, are not the temperatures of plasma into the cavitation bubbles (the intensity of son luminescence), but the power of pressure pulses, which they produce, and which cause destruction of phases existing in a liquid (the intensity of erosion). The distribution of the density power of erosion in space can be the subject of numerically simulated, if it is assumed that process of multibubble cavitation is an ergodic process. For this the integral of pressure superposition from all bubbles of cavitation field at any point in space, must be approximated by the function of the pressure pulse on the surface of a single cavitation bubble, that pulsate with a period equal to the period of oscillations of the harmonic wave. This superposition of pressure can be described using a two metrics of space, which are belongs to this point. The first – the average distance from this a point until all points of the cavitation region. It determines the average time of arrival into this point of a total perturbation of pressure from all bubbles. The second – the average harmonic distance – determines the average coefficient of attenuation of this perturbation. The results of computational and laboratory experiments illustrate the adequacy and the applicability of model. The model makes it possible to quantitatively compare the results of physical and chemical effects of cavitation in the any liquids in the reactors of any size. The model also gives a sufficient degree of accuracy and reliability of performing the technical calculations for the design of such devices and the possibility to make comparative assessments of different reactors. Abstract Full Text (PDF) [Epub] Full Text (HTML)

9.

On the Homotopy Analysis Method for an Seir Tuberculosis Model M.O. Ibrahim, S.A. Egbetade American Journal of Applied Mathematics and Statistics. 2013 1 (4). doi: 10.12691/ajams-1-4-4 Keywords: uberculosis, homotopy analysis method, series solution, nonlinear equations, Mathematica l model Context: In this paper, we provide a very accurate, non-perturbative, semi-analytical solution to a system of nonlinear first-order differential equations modeling the transmission of tuberculosis (TB) in a homogeneous population. Our analysis is based on Homotopy Analysis Method (HAM). Maple 15 software is used to carry out the computations. Our results show the validity and potential of HAM for computing the solution of nonlinear equations. Abstract Full Text (PDF) [Epub] Full Text (HTML)

10.

An Optical and Electrical Modeling of Dye Sensitized Solar Cell: Influence of the Thickness of the Photoactive Layer El Hadji Oumar Gueye, Papa Douta Tall, Cheikh Birahim Ndao, Alle Dioum, Abdoulaye Ndiaye Dione, Aboubaker Chedikh Beye American Journal of Modeling and Optimization. 2016 4 (1). doi: 10.12691/ajmo-4-1-2 Keywords: Dye sensitized solar cell, Bruggeman Theory, Mie Theory, Radiatives Transfers Equations, Mathematica l Modeling, Matlab, Optical Generation Rate, Maximum Power Output, Thickness, Solar Cell Context: Dye sensitized solar cells (DSSC) are used for photovoltaic applications. The paper presents a methodology for optical and electrical modeling of dye-sensitized solar cells (DSSCs). In order to take into account the scattering process, the optical model is based on the determination of the effective permittivity of the mixture and the scattering coefficient using Mie and Bruggeman theories, considering spherical particles. Then, from the radiative transfer equation, the optical generation rate of cell is deduced. Coupling the output of the optical model (the dye generation rate) to an electrical model for charge generation, transport, and first-order (linear) recombination, allows determination of current density and maximum power output. Due to our model, the dependence effects of the thickness of the photoactive layer upon the optical generation rate, the short circuit photocurrent density and the maximum power output are evidenced. Moreover, we see that when the thickness of the photoactive layer increases the optical generation rate increases. While, the short circuit current density and the maximum power output increase until d =10 µm then remain constant. Thereby, it was found that 10 µm of thickness is enough for the best I-V characteristics. Our results agree with those found in the literature. Abstract Full Text (PDF) [Epub] Full Text (HTML)