Understanding the effects of fear, quadratic fixed effort harvesting, and predator-dependent refuge are essential topics in ecology. Accordingly, a modified Leslie–Gower prey–predator model incorporating these biological factors is mathematically modeled using the Beddington–DeAngelis type of functional response to describe the predation processes. The model’s qualitative features are investigated, including local equilibria stability, permanence, and global stability. Bifurcation analysis is carried out on the temporal model to identify local bifurcations such as transcritical, saddle-node, and Hopf bifurcation. A comprehensive numerical inquiry is carried out using MATLAB to verify the obtained theoretical findings and understand the effects of varying the system’s parameters on their dynamical behavior. It is observed that the existence of these factors makes the system’s dynamic behavior richer, so that it involves bi-stable behavior.
Solutions of dyes Rhodamine 6G (Rh6G) and Coumarin480(C480) were prepared at five concentrations (1x10-3, 5x10-4, 1x10-4, 5x10-5 and1x10-5) mol/l, the mixing was stirred to obtain on a homogenous solution, the(poly methyl-methacrylate) (PMMA) was solved by chloroform solvent with certain ratio, afterward (PMMA+Rh6G) and (PMMA+C480) thin films were prepared by casting method on glass block which has substrate with dimensions (7.5 x2.5)cm2, the prepared samples were left in dark place at room temperature for 24 hours to obtain uniform and homogenous thin films. UV-VIS absorption spectra, transmission spectra and fluorescence spectra were done to measure linear refractive index and linear absorption coefficient. The nonlinear optical proper
... Show Morein this article, we present a definition of k-generalized map independent of non-expansive map and give infinite families of non-expansive and k-generalized maps new iterative algorithms. Such algorithms are also studied in the Hilbert spaces as the potential to exist for asymptotic common fixed point.
In the present work, a z-scan technique was used to study the nonlinear optical properties, represented by the nonlinear refractive index and nonlinear absorption coefficients of nanoparticles cadmium sulfide thin film. The sample was prepared by the chemical bath deposition method. Several testing were done including, x-ray, transmission and thickness of thin film. z-Scan experiment was performed at two wavelengths (1064 nm and 532 nm) and different energies. The results showed the effect of self-focusing in the material at higher intensities, which evaluated n2 to be (0.11-0.16) cm2/GW. The effect of two-photon absorption was studied, which evaluated β to be (24-106) cm/GW. In addition, the optical limiting behavior has been studied.
... Show MoreColloidal crystals (opals) made of close-packed polymethylmethacrylate (PMMA) were fabricated and grown by Template-Directed methods to obtain porous materials with well-ordered periodicity and interconnected pore systems to manufacture photonic crystals. Opals were made from aqueous suspensions of monodisperse PMMA spheres with diameters between 280 and 415 nm. SEM confirmed the PMMA spheres crystallized uniformly in a face-centered cubic (FCC) array. Optical properties of synthesized pores PMMA were characterized by UV–Visible spectroscopy. It shows that the colloidal crystals possess pseudo photonic band gaps in the visible region. A combination of Bragg’s law of diffraction and Snell’s law of refraction were used to calculate t
... Show MoreThis research dealt with the subject of negotiation skills of employees in public relations departments which is one of many skills supposed to be available to these employees. These skills combined help in the success of the job of public relations departments; and give them an important and vital role within the roles distributed in the departments of any government institution wither is governmental or non-governmental.
Negotiation is a skill that requires intelligence, tact, culture, information, intuition, and knowing to use the means of communication to access the information that is useful in reaching satisfactory results
... Show MoreThe research aims to verify the presence of correlation between the financial cycle and the economic cycle in the Iraqi economy. During the research period, the Iraqi economy witnessed a crisis cycle due to the permanent deviations in the state budget and the occurrence of sustainable deficits during the period of the economic blockade with the coincidence of an inflationary economic cycle due to the cheap money policy and the occurrence of Negative supply shocks due to the blockade and the madly high general level of prices, in addition to the weak financial planning of the state budget during the post-economic blockade and the entry of the economy into a stagnant economic cycle due to security and political instability, low levels of priv
... Show MoreIn this paper, wireless network is planned; the network is predicated on the IEEE 802.16e standardization by WIMAX. The targets of this paper are coverage maximizing, service and low operational fees. WIMAX is planning through three approaches. In approach one; the WIMAX network coverage is major for extension of cell coverage, the best sites (with Band Width (BW) of 5MHz, 20MHZ per sector and four sectors per each cell). In approach two, Interference analysis in CNIR mode. In approach three of the planning, Quality of Services (QoS) is tested and evaluated. ATDI ICS software (Interference Cancellation System) using to perform styling. it shows results in planning area covered 90.49% of the Baghdad City and used 1000 mob
... Show MoreThe paper has been summarized into the following:
Chapter one: the researcher deals with the problem of the paper, the most important points and the terminology. Chapter two: the researcher deals Surat Luqman from the Aya 12-19 , (the demonstration, the explanations, the values ). In chapter three the researcher deals with Surat AL-Hujurat from Aya 6-12, (the demonstration, the explanations, the values ). Chapter four include (the educational properties for individual and society, the educational applications, and the most important indicators in the texts). Chapter five include the results , the conclusions and the recommendations. One of the basic results that the Quran is a complete educational curriculum, and the texts of Surat Lu