In this paper, the dynamic behaviour of the stage-structure prey-predator fractional-order derivative system is considered and discussed. In this model, the Crowley–Martin functional response describes the interaction between mature preys with a predator. e existence, uniqueness, non-negativity, and the boundedness of solutions are proved. All possible equilibrium points of this system are investigated. e sucient conditions of local stability of equilibrium points for the considered system are determined. Finally, numerical simulation results are carried out to conrm the theoretical results.
In this paper, the error distribution function is estimated for the single index model by the empirical distribution function and the kernel distribution function. Refined minimum average variance estimation (RMAVE) method is used for estimating single index model. We use simulation experiments to compare the two estimation methods for error distribution function with different sample sizes, the results show that the kernel distribution function is better than the empirical distribution function.
A linear and nonlinear theoretical and experimental aeroelastic investigation of a wing-flap-tab typical section model undergoing two-dimensional incompressible airflow is described. The linear flutter velocity (LFV) and frequency are predicted using linear analysis. Then a freeplay structural nonlinearity is considered in the tab. The structural equations of motion have been coupled with Theodorsen aerodynamic theory to produce the theoretical aeroelastic model which is analyzed by a state space method to predict the LFV and flutter frequency. Linear piecewise function has been used to introduce the tab spring stiffness in the freeplay state. The ground vibration test is used to measure the model structural dynamic characteristics. Then th
... Show Morein this paper the second order neutral differential equations are incestigated are were we give some new suffucient conditions for all nonoscillatory
The experiment was conducted to investigate the effect of prey type (Artemia nauplii, mosquito larvae and paramecium) on some reproductive aspects in crustacean zooplankton M. albidus which included reproductive period, post reproductive period, period spend to egg appearance and the period from appearance of egg to nauplii releasing. Results revealed that females fed on mosquito larvae had the highest mean of postreproductive period and lowest mean of the period spend to egg appearance, which differed significantly (P < 0.05) compared with the means of females who fed on Artemia nauplii and paramecium on the other hand the differences were not significant in reproductive period and the period from appearance of egg to nauplii releasing.
The art of Islamic ceramics is considered one of the main pillars of the art of ceramics in the plastic arts, as his knowledge of what is presented in the Islamic arts intertwined in a special way. And the Islamic ceramics are indications of fertility and the rekindling of religious ties, controversy over them, and interpretation as additions to their vocabulary. Studies in the plastic arts began to empty the knowledge towards this direction, especially its relationship to the Arabic calligraphy and specifically the Islamic decoration, which derived the first aesthetic values from calling the artist Muslim pottery and potters to inviting the Arabic letter and Islamic decoration to indicate within the theory of "displacement" the aestheti
... Show MoreTo study the response of the celery plant to nitrogen fertilization and spray with salicylic acid in the leaves content of nutrients, the research was conducted in one of the fields of the Department of Horticulture and Gardening Engineering / College of Agriculture / University of Baghdad within the 2019-2018 season. The research was carried out as a global experiment and with the design of complete randomized sectors (RCBD) and with three replicates, the first factor included the addition of nitrogen with three levels and its symbol (N) (N1 control), (N2) g / m2 18 ), (N3) 37 g / m2 and the second factor spraying acid salicylic is denoted by
Background: Immune thrombocytopenia is an immune-related disorder that causes an impairment in platelet production and stimulates platelet destruction, causing variable bleeding symptoms. Objective: This study focuses on refractory immune thrombocytopenic purpura patients on romiplostim treatment and their level of illness perception related to treatment response. Method: A cross-sectional study was conducted from May 1st, 2025, to August 1st, 2025. Brief Illness Perception Questionnaires were administered to 84 patients with ITP to collect the data. The study took place at the Hematology and Bone Marrow Transplant Center, Medical City, Baghdad, Iraq. Results: The romiplostim response rate is 21 (25.0%), while the partial response rate is 4
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