Journal of Mathematical and Fundamental Sciences
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Comparative Study of the Dynamics of Cosmic Rays for the Pakistan and China Atmospheric Regions
Full text linkThis paper presents an analysis of cosmic ray intensity in Pakistan air space using spatial interpolation, comparing it with Chinese cosmic ray records from 1984 to 1993. The Exploratory Data Analytic (EDA) approach was applied to compare the cosmic ray fluctuations in both countries. The time series plot of the monthly cosmic rays showed relatively flatter counts in Pakistan than in China. The cosmic ray data for the years 1984 to 1993 fell within Solar Cycle 22, which lasted from 1986 to 1996, with its maximum phase in 1989 to 1991. The cosmic radiation varies between the atmospheric regions of Pakistan and China due to modulations in intensity that are accessible accordingly. It can be explained by purely astrophysical phenomena: (1) the source of emission of cosmic radiation may be different, (2) the rate at which emanation takes place depends on bursts of deep space dynamical objects from their sources that may be affected by solar wind and other solar radiations. Therefore, modulations in intensity are not only due to different geophysical locations. This study will help government organizations to predict and forecast cosmic rays values
On Subspace-ergodic Operators
Full text linkIn this paper, we define subspace-ergodic operators and give examples of these operators. We show that by any given separable infinite-dimensional Banach space, subspace-ergodic operators can be constructed. We demonstrate that an invertible operator T is subspace-ergodic if and only if T-1 is subspace-ergodic. We prove that the direct sum of two subspace-ergodic operators is subspace-ergodic and if the direct sum of two operators is subspace-ergodic, then each of them is subspace-ergodic. Also, we investigate relations between subspace-ergodic and subspace-mixing operators. For example, we show that if T is subspace-mixing and invertible, then Tn and T-n are subspace-ergodic for n∈ℕ
Optimal Parameters for Nonlinear Hirota-Satsuma Coupled KdV System by Using Hybrid Firefly Algorithm with Modified Adomian Decomposition
Full text linkIn this paper, several parameters of the non-linear Hirota-Satsuma coupled KdV system were estimated using a hybrid between the Firefly Algorithm (FFA) and the Modified Adomian decomposition method (MADM). It turns out that optimal parameters can significantly improve the solutions when using a suitably selected fitness function for this problem. The results obtained show that the approximate solutions are highly compatible with the exact solutions and that the hybrid method FFA_MADM gives higher efficiency and accuracy compared to the classic MADM method
A Predictor-Corrector Scheme for Conservation Equations with Discontinuous Coefficients
Full text linkIn this paper we propose an explicit predictor-corrector finite difference scheme to numerically solve one-dimensional conservation laws with discontinuous flux function appearing in various physical model problems, such as traffic flow and two-phase flow in porous media. The proposed method is based on the second-order MacCormack finite difference scheme and the solution is obtained by correcting first-order schemes. It is shown that the order of convergence is quadratic in the grid spacing for uniform grids when applied to problems with discontinuity. To illustrate some properties of the proposed scheme, numerical results applied to linear as well as non-linear problems are presented
Stratigraphic Model of East Biak Based on Magnetotelluric Data
Full text linkBiak Island is thought to have originated from the Australian Continental passive margin in the Mesozoic. This passive margin underwent tectonic collision to form the bedrock of Biak Island during the Paleogene. East Biak is covered by limestone, which is an obstacle to knowing the deeper stratigraphy. This study's aim was to identify the subsurface geology of the East Biak area based on rock resistivity values. Magnetotelluric (MT) surveying is a passive geophysical method that is able to interpret subsurface geology based on rock resistivity values at depths of up to 5 to 10 km. The MT measurements in East Biak used 25 measurement points. Cross-sectional variations in rock resistivity values generated from the MT measurements were used to identify rock types in the East Biak subsurface. Five rock units were identified. The East Biak stratigraphy model is dominated by carbonates, comprising two sequences, i.e. an Early Neogene sequence with a thickness of 1,000 to 3,000 m and a Late Neogene to Quaternary sequence with a thickness of 180 to 2,450 m. The unconformity between these two sequences is due to tectonic activity, which separated Supiori and Biak Island
Statistical Forecast of Daily Maximum Air Temperature in Arid Areas at Summertime
No full textBased on historical observations of summers for the period from 2004 to 2018 with a focus on daily maximum and minimum air temperatures and wind speed recorded at 0600 GMT, a non-linear regression hypothesis is developed for forecasting daily maximum air temperature (Tmax) in arid areas such as Baghdad International airport station, which has a hot climate with no cloud cover or rain. Observations with dust storm events were excluded, thus this hypothesis could be used to predict daily Tmax on any day during summers characterized by fair weather. Using mean annual daily temperature range, daily minimum temperature, and the trend of maximum temperature with wind speed, Tmax was forecasted and then compared to those recorded by meteorological instruments. To improve the accuracy of the hypothesis, daily forecast errors, bias, and mean absolute error were analyzed to detect their characteristics through calculating relative frequencies of occurrence. At the end of this analysis, a value of (-0.45ºC) was added to the hypothesis as a bias term
Serum Level of IL-6, Reactive Oxygen Species and Cortisol in Patients with Recurrent Aphthous Stomatitis related Imbalance Nutrition Intake and Atopy
Full text linkOne of the most common oral ulcerations is recurrent aphthous stomatitis (RAS), affecting approximately 20% of the general population worldwide. The etiology of RAS is still unclear but it is considered to be multifactorial, including imbalanced nutrition intake and allergic conditions such as atopy. The purpose of this study was to investigate the differences and correlation between the serum level of IL-6, reactive oxygen species (ROS), and cortisol in RAS patients. Our study was cross-sectional and used a consecutive sampling method. There were significant differences of IL-6 and ROS levels in all groups (p = 0.000, p = 0.049 respectively) and a significant correlation between cortisol and ROS in the RAS group without atopy (r = -0.985, p = 0.015). Serum IL-6 and ROS measurement may be used for detecting RAS caused by malnutrition or atopy but not cortisol for patients without psychological stress detected. This is consistent with the results of a very strong correlation with a negative value between cortisol and ROS in RAS without atopy
Hankel Inequalities for a Subclass of Bi-Univalent Functions based on Salagean type q-Difference Operator
No full textIn this investigation a new subclass of bi-univalent functions is established that is defined in the open unit disk Δ={ðŒ¶ âˆˆ â„‚: |ðŒ¶| < 1} and are endowed with the Sălăgean type q-difference operator. Then, Hankel inequalities for the new function class are obtained and several related consequences of the results are also stated
Restricted Size Ramsey Number Involving Matching and Graph of Order Five
No full textHarary and Miller (1983) started the research on the (restricted) size Ramsey number for a pair of small graphs. They obtained the values for some pairs of small graphs with order not more than four. In the same year, Faudree and Sheehan continued the research and extended the result to all pairs of small graphs with order not more than four. Moreover, in 1998, Lortz and Mengenser gave the size Ramsey number and the restricted size Ramsey number for all pairs of small forests with order not more than five. Recently, we gave the restricted size Ramsey number for a path of order three and any connected graph of order five. In this paper, we continue the research on the (restricted) size Ramsey number involving small graphs by investigating the restricted size Ramsey number for matching with two edges versus any graph of order five with no isolates
A Mathematical Model to Study the Effects of Breastfeeding and Vaccination on Rotavirus Epidemics
Full text linkIn this article, we formulate and analyze a mathematical model including breastfeeding and vaccination to study the transmission dynamics of rotavirus epidemics. The model is divided into five compartmental classes, namely, the susceptible compartment S(t); the breastfeeding compartment M(t); the vaccinated compartment V(t); the infected compartment I(t); and the recovered compartment R(t). To understand the threshold of infection, the basic reproduction number relating to breastfeeding and vaccination, denoted as Rvm, is computed. The results show that if Rvm<1, the disease-free equilibrium is globally asymptotically stable. Similarly, if Rvm>1, global asymptotic stability of the endemic equilibrium exists. Numerical simulations were carried out to support the model analysis and to examine the effects of breastfeeding and vaccination on rotavirus epidemics. The model fits well with real data to predict the infected population in real life. The analysis and numerical results of the model confirm that the combination of vaccination and breastfeeding is more effective in reducing the spread of rotavirus epidemics