Double-layer micro-perforated panels (MPPs) have been studied extensively as sound absorption systems to increase the absorption performance of single-layer MPPs. However, existing proposed models indicate that there is still room for improvement regarding the frequency bands of absorption for the double-layer MPP. This study presents a double-layer MPP formed with two single MPPs with inhomogeneous perforation backed by multiple cavities of varying depths. The theoretical formulation is developed using the electrical equivalent circuit method to calculate the absorption coefficient under a normal incident sound. The simulation results show that the proposed model can produce absorption coefficient with wider absorption bandwidth compared w
... Show MoreBackground: Mental health of children has recently been
receiving increased attention in many parts of the world.
However, such attention has been lacking in developing
countries, particularly in the form of systematic research
Aim: The study aimed to find out the frequency of
behavior disorders in a sample of primary school children
and the different social and demographic factors that might
be related to this disorder.
Methods: The study is a cross-sectional one that included
918 primary school pupils in both urban and rural areas of
Baghdad. Rutter's questionnaire teacher's version was used
to assess the pupils, and the demographic data was obtained
by special questionnaire sent to the parents to be
Aim: The purpose of this study was to analyze the patterns of facial fractures in children and to compare them between preschool- and school-aged children. Materials and methods: This retrospective observational study included 57 children with facial fractures. The variables analyzed were the age of the patients—divided into a preschool-aged group (0–5 years) and a school-aged group (6–12 years)—gender, cause of trauma, the facial bones involved, the pattern of fracture, the modality of treatment used, the time between injury and treatment, and the postoperative complications. Results: The incidence of facial fractures in children ≤12 years was 30.2%. The patients consisted of 40 (70.2%) males and 17 (29.8%) females, and most pati
... Show MoreThe research aims at identifying the level of imaginative thinking skills in mathematics among fourth scientific grade students.For this purpose, the researcher adopted the descriptive (survey) approach, as an imaginative thinking test was built and applied to the research sample that consists of (301) students from fourth scientific grade students who are distributed to secondary and Preparatory schools,they are Al-Furat Preparatory, Al-Hindiya Preparatory school and Al-Rajiba Preparatory school , who are affiliated to the Al-Hindiya Education Department of the General Directorate in the Holy Karbala Governorate for the academic year (2021-2022). The imaginative thinking test consisted of (36) items of four alternatives multiple-choice obj
... Show MoreThe study examines the religious references of the art of miniatures in the Iranian school "Bahzad model" completed in Iran during the twelfth century AH, according to the controls and characteristics of the authoritative references. The researcher presented the problem of research, its importance, the need for it and its purpose, defined the terms in the research. The theoretical framework came with three investigations. The first topic of the concept of the reference in the field of knowledge, which concluded the most important features of the reference, is that each symbolic existence corresponds to a real existence and symbolic presence is an input to the realization of the reference. The reference then becomes a sign that acts as a
... Show MoreIris research is focused on developing techniques for identifying and locating relevant biometric features, accurate segmentation and efficient computation while lending themselves to compression methods. Most iris segmentation methods are based on complex modelling of traits and characteristics which, in turn, reduce the effectiveness of the system being used as a real time system. This paper introduces a novel parameterized technique for iris segmentation. The method is based on a number of steps starting from converting grayscale eye image to a bit plane representation, selection of the most significant bit planes followed by a parameterization of the iris location resulting in an accurate segmentation of the iris from the origin
... Show MoreTwelve species from Brassicaceae family were studied using two different molecular techniques: RAPD and ISSR; both of these techniques were used to detect some molecular markers associated with the genotype identification. RAPD results, from using five random primers, revealed 241 amplified fragments, 62 of them were polymorphic (26%).
ISSR results showed that out of seven primers, three (ISSR3, UBC807, UBC811) could not amplify the genomic DNA; other primers revealed 183 amplified fragments, 36 of them were polymorphic (20%). The similarity evidence and dendrogram for the genetic distances of the incorporation between the two techniques showed that the highest similarity was 0.897 between the va
... Show MoreGhar Formation outcrop at the Iraqi western desert was studied by microfacies analysis
of (13) thin sections collected from wadi Al-Ratgha ( west of Qaim ) . According to
petrographic com position and organisms content ,rocks were subdivided into (4)
microfacies units :bioclastic wackestone , mudstone , miliolids wackestone , and grainstone
with aggregate grains microfacies .Microfacies units reflect shallow marine environment of
low circulation of very warm water at the middle part . The lower and middle part
interbedded with quite open marine environment below the wave base . The upper part was
deposited at shallow marine environment of low circulation . The main diagenetic processes
were the transformation ( ty