The proposed work is an attempt to investigate the stability of the nonlinear system by using a whale optimization algorithm as of one of the meta-heuristic optimization methods, and this investigation was conducted on a single inverted pendulum as a study model. The evaluation measures which were used in this article values of gain and sliding surface of the conventional sliding mode controller to illustrate the extent of the system`s stability. Furthermore, control action, the relationship between error and its derivative, desired, and actual position in addition to sliding response graphically showed the feasibility of the proposed solution. The attained results illustrated considerable improvement in the settling time and minimizing the impact of chattering behavior.
The research aims to examine the evaluation of educational quality management and the ways to improve it in the College of Education for Women at the University of Baghdad from the point of view of the academic staff. The research community consisted of (288) participants comprising all members of the academic staff in the College of Education for Women at the University of Baghdad for the academic year (2019-2020). As for the questionnaire, it was distributed to the academic staff of the scientific departments according to their affiliation for the purpose of identifying the availability of the requirements of the quality of the teaching service provided to them by the educational institution. The researcher adopted a questionnaire deve
... Show MoreBackground: The most crucial mechanism of genetic variation in N. meningitidis is the slipped strand mispairing, this mechanism generates Phase variation using simple sequence repeat (SSR) and is commonly used by the N. meningitidis to escape the immune system despite its function in eradicating the pathogenic and commensal bacteria. Some of simple sequence repeats (SSRs) that located within the genome works as phase variation while other SSRs have no role in generating phase variation mechanisms. Therefore, Aim: the main goal of the current in silico study was to detect the probability of SSR to enroll with phase variation for the entire N. meningitidis genome. Methods: Different criteria were used to judge SSR as
... Show MoreBackground: Wound healing, as a normal biological process in the human body, is achieved through four precisely and highly programmed phases: hemostasis, inflammation, proliferation, and remodeling. Growth factors released in the traumatized area promote cell migration into the wound area (chemotaxis), stimulate the growth of epithelial cells and fibroblasts (mitogenesis), initiate the formulation of new blood vessels (angiogenesis), and stimulate matrix formation and remodeling of the affected region. One of factors that effects on wound healing is a sex hormones and one of these hormones is an estrogen hormone. A wide range of cutaneous cell types (eg, fibroblast, endothelial, epithelial, and inflammatory) expressed estrogen receptors, in
... Show MoreBackground: Cleaning and shaping of root canals successfully requires high volumes of irrigation solutions that can only be applied to the apical third of root canal after enlargement with instrument, so the aim of this study was to evaluate and to compare the efficiency of Maxi-I-probe (side-vented needle), in the amount of root canal irrigant penetration for five different master apical file sizes (MAF) and four different degrees of coronal and middle thirds flaring. Materials and Methods: Two hundred resin blocks with simulated root canals were used in this study and divided into 5 major groups (40 for each) based on the size of master apical files (#20, #25, #30, #35, and #40). Each major group was subdivided into 4 subgroups depending
... Show MoreThe aim of the study was extraction of arial part of Euphorbia cyathophora constituents with methanol and evaluate its effect on mitotic index and total chromosomal aberration bone marrow cell and spleen cell in mice 200 gm of E. cyathophora fine powder was defatted then extracted by cold maceration 80% ethanol for seven days. The extract was filtered and dried in a rotary evaporator then the dried extract was suspended with water and consecutively extracted using chloroform, ethyl acetate for each. The aqueous layer was then mixed with 100ml methanol. These fractions are dried under reduced pressure to obtain the dry extract. Twenty-four Albino mice were used for the experiment. The animals were divided into four groups: Gr
... Show MoreBackground: Entamoeba histolytica is the causative agent of amoebic dysentery and hepatic abscesses. Despite the efficacy of metronidazole in alleviating infectious diseases, the global dissemination of drug-resistant parasites raises the possibility that Punica granatum could serve as an effective natural alternative treatment. Objective: To evaluate the effect of P. granatum methanolic and aqueous extracts of various parts against E. histolytica trophozoites in an in vitro setting. Methods: Various concentrations (0.14, 0.7, 1.4, and 2.8 mg/ml) of P. granatum extracts of the flowers, leafs, peels, and seeds were chosen for this purpose. A culture medium containing 0.05x106/ml E. histolytica trophozoites was treated with different
... Show MoreIn this paper, a Cholera epidemic model is proposed and studied analytically as well as numerically. It is assumed that the disease is transmitted by contact with Vibrio cholerae and infected person according to dose-response function. However, the saturated treatment function is used to describe the recovery process. Moreover, the vaccine against the disease is assumed to be utterly ineffective. The existence, uniqueness and boundedness of the solution of the proposed model are discussed. All possible equilibrium points and the basic reproduction number are determined. The local stability and persistence conditions are established. Lyapunov method and the second additive compound matrix are used to study the global stability of the system.
... Show MorePolycaprolactone is one of the natural biodegradable polymers mainly used in bioplastics production for packaging, usually composed of non-toxic compounds and biodegradable. The aim was to examine the role of zinc oxide (ZnO) nanopowder on the,wettability , thermal and anti-bacterial effect nanocomposites. Pure PCL and PCL-based bio- nanocomposites doped with various ratios of ZnO nanoparticles from 0% to 5wt% were prepared through the arrangement of throwing procedure. The results show that wettability properties in relation to ideal PCL and that they were increasingly hydrophobic from 57º.8 to 69º.53 because add ZnO nanocomposites,the thermal stability between 300 and 400 ° C makes them perfect for the application
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