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 with the conventional double- and even triple-layer MPPs. The bandwidth can be increased to higher frequency by decreasing the cavity depth behind a sub-MPP with small hole diameter and a high perforation ratio, and to lower frequency by increasing the cavity depth behind a sub-MPP with large hole diameter and a small perforation ratio. The experimental data, measured by impedance tube, are in good agreement with the predicted results.
Due to advancements in computer science and technology, impersonation has become more common. Today, biometrics technology is widely used in various aspects of people's lives. Iris recognition, known for its high accuracy and speed, is a significant and challenging field of study. As a result, iris recognition technology and biometric systems are utilized for security in numerous applications, including human-computer interaction and surveillance systems. It is crucial to develop advanced models to combat impersonation crimes. This study proposes sophisticated artificial intelligence models with high accuracy and speed to eliminate these crimes. The models use linear discriminant analysis (LDA) for feature extraction and mutual info
... Show MoreBackground:: Infertility is a very common condition affecting approximately 13-14% of couples in the reproductive age. In general population; about 85% of couples have achieved conception within a year. Intrauterine insemination is one of the procedure which have a role in the treatment of infertile couple.Objectives:is to confirm that the use of ovulation induction in the course of intrauterine insemination elevates the pregnancy success rate.Method:This study had been conducted between December 2013 till December 2014 in AL-Elwiyah maternity hospital and AL-Samaraii hospital / Baghdad.On history and clinical examination; the chosen couple had the following criteria; primary infertility for more than one year, no previous IUI trials, hu
... Show MoreOtitis media with effusion (OME) is the long-term deposition of mucus in the middle ear cleft. It is the leading cause of childhood hearing loss and a common childhood infection. It can impair communication and life quality. OME's direct and indirect costs are also crucial. Improving OME care is crucial. This study examines intranasal mometasone's efficacy in treating otitis media with effusion. A clinical trial study was conducted during a period from January 2021 to June 2022. It included 80 patients suffering from otitis media with effusion bilaterally (160 ears) who had an intact tympanic membrane and tympanometry type B. These patients were included only if they had a hearing change or loss noted by the parents or by the patien
... Show MoreDrones are highly autonomous, remote‐controlled platforms capable of performing a variety of tasks in diverse environments. A digital twin (DT) is a virtual replica of a physical system. The integration of DT with drones gives the opportunity to manipulate the drone during a mission. In this paper, the architecture of DT is presented in order to explain how the physical environment can be represented. The techniques via which drones are collecting the necessary information for DT are compared as a next step to introduce the main methods that have been applied in DT progress by drones. The findings of this research indicated that the process of incorporating DTs into drones will result in the advanc
The main objective of this study is to describe the preparation of topographic maps using the Surfer software. A total of 159 regularly distributed Ground Control Points (GCPs) were collected with the use of the Differential Global Positioning System (DGPS). Seven methods (Contour Map, Post Map, 3D Surface Map, 3D Wireframe Maps, Grid Vector-1 Map, Color Relief Map, and Shaded Relief Maps) at the Surfer environment were used to prepare the topographic maps at the Mukhtar Village near the Al-Fallujah City. Contour lines with other features were superimposed on the DEM layer, which refers to the topography of the terrain inside this study area. The accuracy of the database's results was estimated, essential maps were given, and the re
... Show MoreThe eggshell cuticle is the proteinaceous outermost layer of the eggshell which regulates water exchange and protects against entry of micro-organisms. Outer eggshell and cuticle protein was extracted from domestic chicken. The aim of the research is to find out the effect of the treated and untreated nano particles of egg shells with micro wave cold plasma on the effectiveness of E. coli (negative bacteria) that infect the skin and measure the diameter of bacterial inhibition zone, the eggshell has been prepared by a chemical method (sol gel) and measure the level of acidity and the PH is neutral. The result of Atomic Force Microscope (AFM) shows that the particles diameters become smaller with nano-particles solution than for egg
... Show MoreCollective C2 transitions in 32S are discussed for higher
energy configurations by comparing the calculations of transition
strength B(CJ )with the experimental data. These configurations
are taken into account through a microscopic theory including
excitations from the core orbits and the model space orbits with nħω
excitations.
Excitations up to n=10 are considered. However n=6 seems to
be large enough for a sufficient convergence. The calculations
include the lowest seven 2+0 states of 32S.
In this work we reported the synchronization delay in
semiconductor laser (SL) networks. The unidirectional
configurations between successive oscillators and the correlation
between them are achieved. The coupling strength is a control
parameter so when we increase coupling strength the dynamic of the
system has been change. In addition the time required to synchronize
network components (delay of synchronization) has been studied as
well. The synchronization delay has been increased by mean of
increasing the number of oscillators. Finally, explanation of the time
required to synchronize oscillators in the network at different
coupling strengths.