Fiber Bragg Grating has many advantages where it can be used as a temperature sensor, pressure sensor or even as a refractive index sensor. Designing each of this fiber Bragg grating sensors should include some requirements. Fiber Bragg grating refractive index sensor is a very important application. In order to increase the sensing ability of fiber Bragg gratings, many methods were followed. In our proposed work, the fiber Bragg grating was written in a D-shaped optical fiber by using a phase mask method with KrFexcimer. The resultant fiber Bragg grating has a high reflectivity 99.99% with a Bragg wavelength of 1551.2 nm as a best result obtained from a phase mask with a grating period of 1057 nm. In this work it was found that the rotation of the core of the D-shaped optical fiber that faces the phase mask is very important in determining the quality of written fiber Bragg grating.
The world is currently challenging the serious effects of the pandemic of the Coronavirus disease (COVID-19) caused by severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2). Data on pediatric COVID are rare and scattered in the literature. In this article, we presented the updated knowledge on the pediatric COVID-19 from different aspects. We hope it will increase the awareness of the pediatricians and health care professionals on this pandemic.
In this paper the effect of thermal annealing on the structural and optical properties of Antimony Selenide (Sb2Se3) is investigated. Sb2Se3 powder is evaporated on clean amorphous glass substrates at room temperature under high vacuum pressure (4.5×10-6 mbar) to form thin films. The structural investigation was done with the aid of X-ray diffraction (XRD) and atomic force microscopy (AFM). The amorphous to polycrystalline transformation of these thin films was shown by X-ray diffraction analysis after thermal annealing. These films' morphology is explained. (UV-Vis ) spectra in ranges from 300 to 1100 nm was used to examine the optical properties of the films .The absorption coefficient and optical energy gap of the investigated films are
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This study aims to highlight the role of strategic leadership in adopting the intelligent organization model. The study was conducted on 7 economic organizations in Algeria. The study population consisted of 354 leaders, of whom a random sample of 176 leaders (managers, department heads, division heads, engineers) was selected. The researcher used a questionnaire as the main tool of the study. Statistical analysis and hypothesis testing were conducted using SEM (Structural Equation Modeling) with the aid of SPSS.v26 and AMOS.v24 software. The study concluded with a set of results, most notably: there is a statistically significant direct positive effect between strategic leadership and building intelligent organizations at a significance le
... Show MoreBackground: Soft Laser has been advantageous in medical applications and is widely used in clinical practice. It is applied because it doesn’t cause the significant thermal effects or tissue hurt when irradiated. The blood response to low power laser radiation provides information about processes of laser radiation interaction with live creatures. Objective: The aim of the current work was to evaluate the laser-induced changes of in vitro erythrocyte sedimentation rate (ESR), mean corpuscular volume (MCV), and mean corpuscular hemoglobin concentration (MCHC) in patients with breast cancer by irradiating a human blood sample using a green laser and comparing its effects before and after irradiation with the same power density (100mW/c
... Show MoreOne of the most important challenges facing the development of laser weapons is represented by the attenuation of the laser beam as it passed through the layers of atmosphere.This paper presents a theoretical study to simulate the effect of turbulence attenuation and calculates the decrease of laser power in Iraq. The refractive index structure C_n^2 is very important parameter to measure the strength of the atmospheric turbulence, which is affected by microclimate conditions, propagation path, season and time in the day. The results of measurements and predictions are based on the Kolmogorov turbulence theory. It was demonstrated by simulations that the laser weapons in Iraq were severely affected due to the large change in temperatures,
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Background: Apicoectomy and retrograde filling is indicated when conventional endodontic treatment is impossible or failed to achieve apical seal. The aim of this study was to evaluate the effect of ER: YAG laser on apical microleakage. Materials and Methods: Sixty extracted single-rooted teeth were used in this study. The roots were divided into six groups. Group 1: apicoectomy by fissure bur, and apical cavities prepared by round bur, then cavities were filled with MTA. Group 2: the roots preparations and fillings were the same as group 1, then the apical areas were treated by Er:YAG Laser. Group 3: apicoectomy by fissure bur, and apical cavities prepared by ultrasound retrotip and cavities were filled with MTA. Group 4: the roots prepara
... Show MoreThe behavior investigation of castellated beams with fiber-reinforced lightweight concrete deck slab as a modified choice for composite steel-concrete beams affected by harmonic load is presented in this study. The experimental program involved six fixed-supported castellated beams of 2140mm size. Three types of concrete were included: Normal Weight Concrete (NWC), Lightweight Aggregate Concrete (LWAC), and Lightweight Fiber-Reinforced Aggregate Concrete (LWACF). The specimens were divided into two groups: the first comprised three specimens tested under harmonic load effect of 30Hz operation frequency for 3 days, then the residual strength was determined through static load application. The second group included three specimens ide
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Thick films of poly(vinyl chloride)(PVC)& PVC doped with Zn(etx)2 salt complex have been prepared by cast method with fixed thickness almost (120±5) Microns. Optical studies were carried out in the wavelengths region(200-900)nm based on absorption & transmition measurement. Optical parameters such as absorption coefficient(?) ,refraction index(n) and extinction coefficient(K) were observed to be effected by adding the dopant.Electrical parameters such as real(?)& imaginary(?) part of dielectric constant were also calculated part of dielectric constant were also calculated from the optical parameters using Maxwell equation.
A water resources management for earthen canal/stream is introduced through creating a combination procedure between a field study and the scientific analytical concepts that distinguish the hydraulic problems on this type of stream with using the facilities that are available in HECRAS software; aiming to point the solutions of these problems. Al Mahawil stream is an earthen canal which is subjected to periodic changes in cross sections due to scour, deposition, and incorrect periodic dredging processes due to growth of the Ceratophyllum plants and weeds on the bed and banks of the stream; which affect the characteristics of the flow. This research aims to present a strategy of water resources management through a field study that conducte
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This research aims to define the roles of auditors by clarifying the concept and risks of cyber security in protecting information and financial data in economic units. Najaf, Babylon and Karbala, then the results were analyzed and the results were presented and analyzed to show that adopting cyber security improves the quality of reports Finance through what it achieves in displaying information with credibility and transparency, in a way that suits the needs of users, and cyber security has a role in managing economic resources more effectively to obtain benefits that would have been lost in the event of an
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