Univesity of Thi-Qar Journal

Four seismic refraction profiles for both compressional (P) and shear (S) waves had been surveyed within AlKifil District/Babylon Governorate, Middle of Iraq, by the use of three impacts; normal, center and reverse shootings. In addition, cross-hole, down-hole and up-hole seismic refraction using couple boreholes were also conducted in the investigated site. These two techniques were done in order to delineate depths and thicknesses of the layers (soils), their dynamic elastic modulus and groundwater level underlying such establishment building may use for future landfill purposes.
The calculations demonstrate that there are two shallow subsurface layers were found. The average of velocities and thicknesses of the first layer (consists of grayish silty sandy clay soil) are equal to 259.33, 147.83 m/sec and 6.58 m, and for the second one (consists of brownish and greenish silty clay soil with sand) are 517, 273.25 m/sec for each P and S-waves respectively. On the other hand, mean water table seems between 1.40 and 1.20 meters during Sep. 2012 and Sep. 2015 respectively. Moreover, the mean dynamic elastic constants were ranged between {κ= (69.51-605.16) Mpa, μ= (24.64-212.37) Mpa, E= (60.40-510.93) Mpa, λ= (41.85-392.22) Mpa, and, σ= (0.18-0.37)}.
Site engineering information including physical and geotechnical properties were also measured and analyzed to enhance the main targets of this study. Standard penetration test and bearing capacity values were performed and calculated for the studied soils. The average of the N-values in situ is equal to (11) impacts having bearing capacity (6.10) ton/m2 at (1.5) m depth interval. It noticed that the N-value is low near the ground surface because of the saturated clay existence (medium consistency). At depth intervals between (13-15)m, the N-value was reached (43) impacts and more; this indicates that the soil is cohesion and contains high percent of sand and low clays; therefore, all depth intervals or layers in the drilling wells are considered hard media and they have bearing capacity equals to (16) ton/m2. This means that the layers corresponding to these intervals were characterized by its hardness.

Er3+doped TiO2 composites were synthesized by using the simple mixing process in order to study the effect of a rare earth metal ions (erbium) on the spectroscopic and structural properties of nano titanium dioxide. Three distinct erbium concentrations “10-2, 10-3, and 10-4 gm/cm3” were used for the spectroscopy study of TiO2Er+3 compounds.. The corresponding fluorescence emission spectra were measured and compared using an excitation wavelength at 350 nm. The effect of Er+3 concentration on the composition and optical properties of nano-TiO2 was studied. Structural and spectroscopic analysis confirm the presence of Er3+ in the composition and that it plays an important role in the upward shift of fluorescence. X-ray diffraction was used to examine the structural features of this material. In the XRD patterns, there were no extra peaks related to any polymorph of TiO2 or contaminants, demonstrating that Er3+ was effectively integrated as a dopant. Through this work, the possibility of the existence of titanium nanoparticles doped with rare earths for optical applications becomes clear.

From an ecological standpoint, the dynamics of the food chain model under the fear that is thus placed on the predator population and the inuence of cooperative hunting among them are quite significant. In the current paper, we use the food chain Lotka-Volterra predator-prey model to examine the effects of hunting cooperation among middle predators and top-predator-induced fear in the middle predator population. The system has four points of equilibrium. The model\'s dynamical characteristics are studied. It has been discovered that dynamical behavior is quite sensitive to parameter values and displays a range of dynamics without degenerating into chaos and that the presence of cooperation and fear signicantly affects the stability of the dynamics of the system. Computer simulations have been used to illustrate the theoretical results.

In this paper we will review the concepts of discriminant analysis which is one of the important multivariate statistical analysis methods. It is used in various scientific, particularly the studies that are concerned with classification and prediction. It is having discriminant function which has an ability to distinguish between observations and then is classified the observations into two groups or more than it.
It belongs to it depending on a special function called (the discriminant function), which is a linear combination between the independent variables and the dependent variable, which is of the nominal type. The main objective of this research was to address the subject of discriminant analysis from its early beginnings, present the studies and research that concerned it, how the linear discriminant function developed, and then propose new discriminatory functions such as the quadratic and logistic discriminant functions. It also presented the basic concepts of classification processes, conditions and assumptions that must be available to apply the discriminant analysis method, and then dealt with the Robust Discriminant Analysis method, which dealt with the problems of the presence of outliers among the data under study, which violate the basic assumptions of applying the discriminant analysis method, such as the hypothesis of the normal distribution of data.