Purpose: The research aims to estimate models representing phenomena that follow the logic of circular (angular) data, accounting for the 24-hour periodicity in measurement. Theoretical framework: The regression model is developed to account for the periodic nature of the circular scale, considering the periodicity in the dependent variable y, the explanatory variables x, or both. Design/methodology/approach: Two estimation methods were applied: a parametric model, represented by the Simple Circular Regression (SCR) model, and a nonparametric model, represented by the Nadaraya-Watson Circular Regression (NW) model. The analysis used real data from 50 patients at Al-Kindi Teaching Hospital in Baghdad. Findings: The Mean Circular Error (MCE) criterion was used to compare the two models, leading to the conclusion that the Nadaraya-Watson (NW) circular model outperformed the parametric model in estimating the parameters of the circular regression model. Research, Practical & Social Implications: The recommendation emphasized using the Nadaraya-Watson nonparametric smoothing method to capture the nonlinearity in the data. Originality/value: The results indicated that the Nadaraya-Watson circular model (NW) outperformed the parametric model. Paper type Research paper.
The current study used extracts from the aloe vera (AV) plant and the hibiscus sabdariffa flower to make Ag-ZnO nanoparticles (NPs) and Ag-ZnO nanocomposites (NCs). Ag/ZnO NCs were compared to Ag NPs and ZnO NPs. They exhibited unique properties against bacteria and fungi that aren't present in either of the individual parts. The Ag-ZnO NCs from AV showed the best performance against E. coli, with an inhibition zone of up to 27 mm, compared to the other samples. The maximum absorbance peaks were observed at 431 nm and 410 nm for Ag NPs, at 374 nm and 377 nm for ZnO NPs and at 384 nm and 391 nm for Ag-ZnO NCs using AV leaf extract and hibiscus sabdariffa flower extract, respectively. Using field emission-scanning electron microscopes (FE-
... Show MoreA series of new aromatic polyesters have been synthesized by polycondensation of different aromatic diols (M1, M2 ,M3) with different dicarboxlic acids (4,4'azo di benzoic acid, malic acid and adipic acid) using dibutyltine dilaurate as catalyst . The preparation of thermally stable polyesters was successfully applied with good yields (60-85%). All polyesters (PE1-PE4) containing aliphatic methylene linkage, and azo group in the main chain. The resulted polymers are readily soluble in aprotic polar solvents , such as (pyridine , CHCl3 , CH2Cl2 , NaOH , H2SO4 , HNO3 , acetone , benzene , DMF , DMSO , THF) without need for heating. Thermal analysis of polyesters by Thermo Gravimetric Analysis (TGA) reveals that these aromatic polyesters po
... Show MoreThe study aimed to reveal the obstacles of administrative creativity among the leaders of secondary schools (the curriculum system) in the northern border region, which relate to the obstacles (organizational, motivational, and psychological). In addition, to identify the most important statistical differences between the responses of the members of the study sample, which attribute to the variables (educational qualification, year’s Administrative expertise). To achieve the goal of the study, the researcher used the descriptive analytical approach, and to verify the validity of the tool, it has presented to several referees and faculty members in the educational field. The validity of the internal consistency was also calculated for t
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The current research variables have received increasing attention in the recent period because they are one of the important issues affecting the future of organizations, as a result of the speed of environmental variables that have greatly affected organizations and for the purpose of explaining the relationships and links between research variables, as this research presents a test "the type and direction of the relationship between strategic foresight capabilities As an independent variable and green creativity "as a respondent variable. A set of questions has arisen about the basic research problem, including what is the nature and level of interest in the research variables (strategic foresight capabilities an
... Show MoreNew complexes of the type [ML2(H2O)2] ,[FeL2(H2O)Cl] and [VOL2] were M=Co(II),Ni(II) and Cu(II) ,L=4-(2-methyl-4-oxoquinazoline-3(4H)-yl) benzoic acid were synthesized and characterized by element analysis, magnetic susceptibility ,molar conductance ,FT-IR and UV-visible. The studies indicate that the L acts as doubly monodentate bridge for metal ions and form mononuclear complexes. The complexes are found to be octahedral except V(IV) complex is square pyrimde shape . The structural geometries of compounds were also suggested in gas phase by theoretical treatments, using Hyper chem-6 program for the molecular mechanics and semi-empirical calculations, addition heat of formation(?Hf ?) and binding energy (?Eb)for the free ligan
... Show MoreAt the beginning of 1935 theMinistry of (Yasin AL-Hashimi) was formed which was the result of the (Sulayikh)Conference .The new ministys policy was towards the authority of the one party and the exclusivity of power.The policy of (Yasin AL-Hashemi)has faced severe campaigns from the AL-Ekhaa and AL-Ahaly newspapers.The new ministry like its predecessor ministries . When it faces criticism from opposition newspapers .its shutting down newspapers and not accepting requests for them. Some opposition newspapers named Yassin AL-Hashemi (the dictator).Iraqi opposition newspapers have been neglected and deprived of press freedom although they were the main factor in educating the community and representing the public opinion of people . Lt appe
... Show More The present study aimed at ((building an educational -learning design based on the theory of Merrill in (CDT) and measuring the effectiveness of this design in the motivation and achievement of the high school fifth grade students to art education in the subject of the history of modern art)). The research community is made of fifth grade preparatory students in the secondary school of Umm Ayman in the Directorate of Education of Baghdad / Ar-Rusafa in a simple random way. The study sample (58 students) was chosen from section (e) to study according to Merrill theory (CDT) and section (d) to study according to the traditional way.
The pilot design of the control and experimental equivalent groups that have partial control in t
The possibility of using activated carbon developed from date palm seeds wastes as a permeable reactive barrier (PRB) to remove copper from polluted shallow groundwater was investigated. The activated carbon has been developed from date palm seeds by dehydrating methods using concentrated sulfuric acid. Batch tests were performed to characterize the equilibrium sorption properties of new activated carbon in copper-containing aqueous solutions, while the sandy soil (aquifer) was assumed to be inert. Under the studied conditions, the Langmuir isotherm model gives a better fit for the sorption data of copper by activated carbon than other models. At a pilot scale, One-dimensional column experiments were performed, and an integrated model ba
... Show MoreThe current study sheds light on the measurement and estimation of the radioactivity of radionuclides (238U, 226Ra, 232Th, and 40k) in natural waters of different regions of Nineveh Governorate in Iraq.15 samples were collected from different sources of natural waters, where gamma-ray spectroscopy was used using NaI)TI) sodium iodide detector to determine the concentration of radioactivity in the samples. According to the results, the radioactivity concentration in the tested water sample were ranged from 0.36 ± 0.04-1.57 ± 0.09with an average value of 0.69 ± 0.06 Bq/l for 238U, and 2.9 ± 0.02-0.88 ± 0.03 with an average value of 0.65 ± 0.03 Bq/l for 226Ra Bq/l
... Show MoreThe imposition of (state) policy on the South Kuril Islands.In the Pacific was a subject
of borders dispute between Japan and Soviet Union which appeared clearly afterthe second
Great War and during the cold war. Despite the end of the Cold War and the collapse of the
Soviet Union in 1991, this conflict has continued, thus both countries had to made a historic
and legitimate claims to demand the rights of sovereignty and ownership of four islands
occupied by the Soviet Union after World War II under the international conventions and
treaties, but these claims are proven failures through the continuation of the regional conflict.