| | Robust Speaker Recognition in Noisy Conditions by Means of Online Training with Noise Profiles| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Robust Speaker Recognition in Noisy Conditions by Means of Online Training with Noise Profiles | | المؤلف : | Ahmed Hani Al-Noori | | البريد الالكتروني : | | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | PHILIP DUNCAN | | المستفيدين : | | | المستخلص : | Automated speaker recognition attains impressive reliability when tested under controlled laboratory acoustic conditions. The environmental noise that inevitably presents in many realworld speech samples causes considerable degradation of recognition accuracy due to the socalled “channel mismatch” that occurs between the enrollment and recognition phases. A new online training method is proposed in this paper to improve robustness of speaker recognition in noisy conditions. An estimate of the signal to noise ratio and the emulated ambient noise spectral profile found in the silence intervals of the speech signal are used to re-enroll the reference model for a claimed speaker to generate a new noisy reference model. The proposed online training method has been examined and validated using an MFCC-GMM UBM based speaker recognition system. Results show significant improvement in performance | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | | | الرابط : | DOI: https://doi.org/10.17743/jaes.2019.0004 |
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| | | Mechanical Properties Enhancement of Conventional Glass Ionomer Cement by Adding Zirconium Oxide Micro and Nanoparticles| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Mechanical Properties Enhancement of Conventional Glass Ionomer Cement by Adding Zirconium Oxide Micro and Nanoparticles | | المؤلف : | Ali N. Alobiedy | | البريد الالكتروني : | alaoyaftermysoul@gmail.com | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | Ali H. Alhille, Ahmed R. Al-Hamaoy | | المستفيدين : | | | المستخلص : | The aim of this work is to enhance the mechanical properties of the glass ionomer cement GIC (dental materials) by adding Zirconium Oxide ZrO2 in both micro and nano particles. GIC were mixed with (3, 5 and 7) wt% of both ZrO2 micro and nanoparticles separately. Compressive strength (CS), biaxial flexural strength (BFS), Vickers Microhardness (VH) and wear rate losses (WR) were investigated. The maximum compression strength was 122.31 MPa with 5 wt. % ZrO2 micro particle, while 3wt% nanoparticles give highest Microhardness and biaxial flexural strength of 88.8 VHN and 35.79 MPa respectively. The minimum wear rate losses were 3.776μg/m with 7 wt. % ZrO2 nanoparticle. GIC-containing ZrO2 micro and nanoparticles is a promising restorative material with improved mechanical properties expect wear rate losses. | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | Glass ionomer cement, ZrO2 micro and nanoparticles, Mechanical properties, Riva self-cure | | الرابط : | https://doi.org/10.31026/j.eng.2019.02.05 |
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| | | Design and Simulation of Stand-alone PV System for Electronic and Communications Engineering Department Laboratories in Al-Nahrain University| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Design and Simulation of Stand-alone PV System for Electronic and Communications Engineering Department Laboratories in Al-Nahrain University | | المؤلف : | Anas Lateef Mahmood | | البريد الالكتروني : | | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | | | المستفيدين : | | | المستخلص : | In Iraq the problem of electricity shutdown in the main supply still exists and the cuts may last for hours. This shutdown causes problems in lectures and students experiments in the colleges because all electrical devices are off. PV system is a good alternative source to overcome such a problem; therefore a stand-alone photovoltaic power system is presented in this paper to supply department laboratories to ensure power continuity. A stand-alone PV system is presented to supply three laboratories selected as a case study, these laboratories belong to the electronic and communications engineering department, Al-Nahrain University, Baghdad. The loads for these laboratories were calculated based on what are exists already from electrical devices assuming that they were fully on during work time. The Pvsyst6 software package is used for simulation purposes in this work. | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | | | الرابط : | https://www.researchgate.net/publication/330765099_Design_and_Simulation_of_Stand-alone_PV_System_for_Electronic_and_Communicatio ns_Engineering_Department_Laboratories_in_Al-Nahrain_University |
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| | | study on kinetic and optimization of continnous advanced oxidative decolorization of brilliant reactive rad dye | العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | study on kinetic and optimization of continnous advanced oxidative decolorization of brilliant reactive rad dye | | المؤلف : | Khalid M. Mousa | | البريد الالكتروني : | khalidmousa15@gmail.com | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | Forqan M. Hameed | | المستفيدين : | Ministry of Health ,Ministry of Industry and Minerals ,Ministry of Environment | | المستخلص : | | | المستخلص باللغة العربية : | The azo dye brilliant reactive red K-2BP (λmax = 534 nm)is widely used for coloring textiles because of its low-cost and tolerance fastness properties. Wastewaters treatmentthat contains the dye by conventional ways is usually inadequate due to its resistance to biological and chemical degradation. During this study, the continuous reactor of an advanced oxidation method supported the use of H2O2/sunlight, H2O2/UV, H2O2/TiO2/sunlight, and H2O2/TiO2/UV for decolorization of brilliant reactive red dye from the effluent. The existence of an optimum pH, H2O2concentration, TiO2concentration, and dye concentration was taken from the batch reactor experiments. The best conditions were pH=3, H2O2dosage = 500 ppm, TiO2=100ppm and dye concentration=15 ppm .Under the most effective conditions, complete removal of the dye solution was achieved with different flow rates (10, 30, 60) ml/min. At flow rate of 10 ml/min, the percentage of decolorization were (80.47%, 84.65%, 89.42%, 77.5%) and at 60 mL/min (65.19%, 68.26%, 70.01%, 56.8%) for H2O2/sunlight, H2O2/UV, H2O2/TiO2/sunlight and H2O2/TiO2/UV respectively. Results of degradation information showed that the decolorization method was pseudo-first-order kinetics | | كلمات مفتاحية : | sunlight,photochemical oxidation,waste waterReactive Red, Photodegradation, advanced oxidation processes (AOP), Wastewater, Sunlight | | الرابط : | |
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| | | comparative studied of degradation of texlile brilliant rad dye using H2O2,Tio2,UV and sunlight | العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | comparative studied of degradation of texlile brilliant rad dye using H2O2,Tio2,UV and sunlight | | المؤلف : | Khalid M. Mousa | | البريد الالكتروني : | khalidmousa15@gmail | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | Forqan M. Hameed | | المستفيدين : | Ministry of Health ,Ministry of Industry and Minerals ,Ministry ofHigher Education and Scientific Research | | المستخلص : | In this study sunlight and UV radiation were used to compare the efficiency of decolorization of textile wastewater containing brilliant reactive red dye K-2BP (λmax = 534 nm) by the advanced oxidation process (AOP) using (H2O2/sunlight, H2O2/UV, H2O2/TiO2/sunlight, and H2O2/TiO2/UV). The results studied the effect of solution pH, applied H2O2concentration, TiO2concentration (nanoparticle), and initial dye concentration were studied. The experimental results showed that decolorization percentage with H2O2/sunlight and TiO2/H2O2/sunlight under the following conditions: -reaction time 150 of minutes, [ 500 ppm] H2O2, [100 ppm] TiO2, pH=3, initial dye concentration =15 ppm and at ambient temperature were 95.7% and 98.42% respectively. For the same conditions using H2O2/UV, H2O2/TiO2/UV, the percentage of decolorization were 97.85% and 96.33% respectively. The results also indicated that the sunlight is more economic and cost-effective than UV radiation | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | sunlight,photochemical oxidation,brilliont, | | الرابط : | |
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| | | Biocompatibility study of multi-layered hydroxyapatite coatings synthesized on Ti-6Al-4V alloys by RF magnetron sputtering for prosthetic-orthopaedic implant applications| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Biocompatibility study of multi-layered hydroxyapatite coatings synthesized on Ti-6Al-4V alloys by RF magnetron sputtering for prosthetic-orthopaedic implant applications | | المؤلف : | Dunya Abdulsahib Hamdi | | البريد الالكتروني : | Dunia_sh_7@yahoo.com | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | Zhong-Tao Jiangb, Kwangsoo Noc, M. Mahbubur Rahmanb,d,⁎, Ping-Chin Leee, Linh Nguyen Thi Trucf, Jaegyu Kimc, Mohammednoor Altarawnehb, L. Thairg, Thamir Abdul-Jabaar Jumaah, Bogdan Z. Dlugogorskib | | المستفيدين : | | | المستخلص : | Triple-layered RF magnetron sputtered HAp/Al2O3/TiO2 coatings synthesized onto Ti-6Al-4V alloys were studied to improve the surface biocompatibility and corrosion resistance features. It was seen that the HAp layers played asubstantial rolein thebiocompatibility, whilethe intermediate Al2O3/TiO2 layers wereused to enhance the corrosion behavior of the substrate. XRD results showed anenhanced crystallinity along with the (211) HAp phase after the simulated body fluid (SBF) immersion experiment. Local electronic and chemical bonding states of atomic phosphorus and calcium phosphate groups in the coatings, before and after immersion process, were confirmed via XPS studies. The electrochemical impedance spectroscopy (EIS) evaluated the corrosion, which indicated a reduction in capacitance values and a significant improvement of the corrosion resistance of such coatings; with improved bio-medical properties of Ti alloys. | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | | | الرابط : | |
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| | | Preparation and characterization of magnetic nickel nanoparticles by chemical reduction reaction | العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Preparation and characterization of magnetic nickel nanoparticles by chemical reduction reaction | | المؤلف : | Saad H. Ammar | | البريد الالكتروني : | saad_cheminet@yahoo.com | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | Natheer Nori Ismail, Marwa F. Abdul Jabbar | | المستفيدين : | | | المستخلص : | The efficiency of many of conversion-processes in petroleum and industrial improves upon application of materials with the nanosized scale dimension, which is caused by enhancements and advances of improved properties asthe particle size decreases. Nickel nanoparticleshas numerousapplications in petroleum industry with its own catalytic in additional to the magnetic properties. In this study,high purity nanosized magnetic nickel particles has been effectively prepared by chemical reduction of nickel chloride using hydrazinehydrate as reducing agent in aqueous solutions containing ethylene glycol and waterand using polyvinylpyrrolidone (PVP) as anti-agglomeration agent. NanosizedNi particles samples with different hydrazineto nickel chloride mole ratios and PVP to nickel chloride ratios were obtained at constant temperature of 80 °C. The morphology and structural properties of the produced magnetic nickelnanoparticles were characterized by powder XRD and AFM methods. XRD study revealed that the prepared nanoparticles were pure nickel nanoparticles without considerable oxides or other impurity phases. AFM test revealed that all prepared Ni nanoparticles was in nano scale, it was stated that Ni nanoparticles size was very affected by the hydrazine/nickel mole ratio. Experimental results showed that particle size decreases from 94.35 nm to 71.48 nm when increases the [N2H4]/[Ni2+] molar ratio from 15:1 to 45:1. | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | | | الرابط : | |
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| | | MPPT using PSO Algorithm for PV System Supplying Outdoor BTS| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | MPPT using PSO Algorithm for PV System Supplying Outdoor BTS | | المؤلف : | Nada Tarik Abdul Jabar | | البريد الالكتروني : | | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | Anas Lateef Mahmood | | المستفيدين : | | | المستخلص : | The problem of continued power outages in Iraq which has been going on for more than 30 years is making it difficult to provide energy to BTS. The best alternative solution to providing electricity to these areas is through the use of stand-alone solar energy systems. In this study, the PSO algorithm was used for the purpose of finding the Maximum Power Point (MPP) of a proposed stand-alone solar energy system to supply power to the mobile BTS used in Iraq. Through field visits to some BTS in various mobile phone companies operating in Iraq such as Zain, Umniah and Huawei it is show that there are no alternative systems to supply electricity to these towers in the case of main power interruption except the rely on diesel generators. Some simple solar energy systems were found in these companies to charge the batteries for the outdoor BTS to ensure the continuity of electricity to the BTS but just for a few minutes until the operation of diesel generator which causes known problems such as environmental pollution and noise. The proposed system contains from solar panels, buck-boost converter and the tracking algorithm to provide power to a BTS, the system was simulated for different partial shading conditions using MATLAB 2017 a package for two systems 1560 W and 18 kW. The PSO algorithm shows good results in maximum power point tacking for the proposed stand-alone solar energy system, especially, in the case of partial shading in contrast to the P&O method which shows its failure some times to find the maximum power point. The results shows that the PSO method is better and faster than the P&O method in the case of partial shading in case of small power system (1560 W) while for large power system (18765 W) the results proved that PSO was able to reach the MPP at high accuracy but slower than in small systems in case of partial shading | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | | | الرابط : | http://medwelljournals.com/abstract/?doi=jeasci.2019.2707.2715 |
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| | | oli fouling in double - pipe heat exchnger under liquid-liquid dispersion and the influence of copper oxide nanofluid| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | oli fouling in double - pipe heat exchnger under liquid-liquid dispersion and the influence of copper oxide nanofluid | | المؤلف : | Hasan S. Majdi | | البريد الالكتروني : | hasansm@yahoo.com | | جهة انتساب المؤلف : | Department of Chemical Engineering and Petroleum Industries, Al-Mustaqbal | | المشاركين : | Hussein A. Alabdly, Basim O. Hasan, Mustafa M. Hatha | | المستفيدين : | | | المستخلص : | Dispersions of oil in water are encountered in a variety of industrial processes leading to a reduction in the performance of the heat exchangers when thermally treating such two phase fluids. This reduction is mainly due to changes in the thermal and hydrodynamical behavior of the two phase fluid. In the present work, an experimental investigation was performed to study the effects of light oil fouling on the heat transfer coefficient in a double‐pipe heat exchanger under turbulent flow conditions. The effects of different operating conditions on the fouling rate were investigated including: hot fluid Reynolds number (the dispersion), cold fluid Reynolds number, and time. The oil fouling rate was analyzed by determining the growth of fouling resistance withtime and through pressure drop measurements. The influence of copper oxide (CuO) nanofluid on the fouling rate in the dispersion was also determined. It was found that the presence of dispersed oil causes a reduction in heat transfer coefficient by percentages depending on the Reynolds number of both cold and hot fluids and the concentration of oil. In addition, the time history of fouling resistance exhibited different trends with the flow rates of both fluids and its trend was influenced appreciably by the presence of CuO nanofluid. | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | copper oxide,dispersion,double-pipe heat exchanger | | الرابط : | |
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| | | Biomineralization based remediation of cadmium and nickel contaminated wastewater by ureolytic bacteria isolated from barn horses soil| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Biomineralization based remediation of cadmium and nickel contaminated wastewater by ureolytic bacteria isolated from barn horses soil | | المؤلف : | Hussein J. Khadim | | البريد الالكتروني : | husseinjabar80@yahoo.com | | جهة انتساب المؤلف : | Environmental Engineering Department, University of Baghdad, Baghdad, Iraq | | المشاركين : | Saad H. Ammar , Shahlaa E. Ebrahim | | المستفيدين : | | | المستخلص : | Environmental contamination by toxic heavy metals such as cadmium and nickel is a serious problem. Metal carbonate precipitation has been suggested based on urea decomposition for use in wastewater and soil remediation applications. Therefore, Cd(II) and Ni(II) removal was examined from an environmental viewpoint. In this work, biomineralization of cadmium and nickel in aqueous solutions by sixurease-producing bacterial strains isolated from barn horse’s soil samples has been investigated based on microbially induced precipitation (MIP). The enzyme urease produced by these bacteria can hydrolyze urea to carbonate ions leads to increase pH of the wastewater which results in mineralization of the heavy metal ions and their final conversion to metal carbonates precipitates. Only two bacterial strains have been adopted depending on their ability to tolerate high concentrations of toxic metal ions. Bioprecipitation of Cd(II) and Ni(II) was assessed by consideration some factors that affecting on metal bioprecipitation process. These factors include metal toxicity to the bacteria (in term of initial metal concentration) and treatment time. The bioprecipitates were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The selected bacterial isolates demonstrated high endurance with toxic heavy metals and therefore, high Cd(II) and Ni(II) removal rates, ranging from 96% for cadmium to 89% for nickel following incubation for 48 h and at 500 mg/L initial concentration of each Cd(II) and Ni(II). Furthermore, coprecipitation of Cd(II) and Ni(II) with calcite precipitation has been also performed and the results demonstrated that this technique can be beneficial for Cd(II) and Ni(II) biosequestration | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | Cadmium,Nickel ,CdCO3,NiCO3,Biomineralization,Bioremediation | | الرابط : | |
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| | | EFFECT OF ADDING ALUMINIUM MICROPARTICLES TO CONVENTIONAL GLASS IONOMER CEMENT| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | EFFECT OF ADDING ALUMINIUM MICROPARTICLES TO CONVENTIONAL GLASS IONOMER CEMENT | | المؤلف : | Howrah M.A. Abbas | | البريد الالكتروني : | | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | Ahmed R. Alhamaoy | | المستفيدين : | | | المستخلص : | Glass Ionomer Cement (GIC) is one of the important dental materials used in dental clinics, which is usually used in temporary restorative stages. This study aims to evaluate the effect of adding Al micro particles to GIC powder (Riva self-cure) on the mechanical and physical properties. The results showed that the addition of Al micro particles has improved the compressive strength and biaxial flexural strength where the highest values were at 3 wt. %, and then the compressive strength and biaxial flexural strength decreased with increasing the added ratios. The addition of Al particles improved the surface Vickers microhardness values where the highest value was at 5 wt. %. The addition of Al has decreased the wear resistance of GIC; however the wear resistance increased with increased adding ratios. The most acidic beverages (the lowest value of pH) were the most effective in increasing the absorption and solubility percentage of Al samples. Orange juice was more effective followed by cola and then coffee and tea were less effective. We recommend that patients reduce these acidic beverages because they have a harmful effect on dental fillings. | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | Glass Ionomer Cement; Al micro particles; Mechanical Properties; Physical Properties; Riva self-cure | | الرابط : | |
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| | | Brain-Computer Interface Based on VEP and FMRI Package| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Brain-Computer Interface Based on VEP and FMRI Package | | المؤلف : | Hadeel K. AlJobouri | | البريد الالكتروني : | hadeel_bme77@yahoo.com | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | Faten Emad Ali | | المستفيدين : | | | المستخلص : | A Brain-Computer Interface (BCI) is a construction that measures signals produced by the central nervous system (CNS) to perform the desired action or used for rehabilitation next stroke or any other disorders. In this paper, a new educational tool is designed and implemented using two functional data in the same package. Visual Evoked Potential (VEP) and functional Magnetic Resonance Imaging (fMRI) are designed in the same MATLAB-based Graphical User Interface (GUI). This work presented a new comparison between fMRI and VEP techniques. | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | | | الرابط : | |
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| | | Multispectral imaging: Monitoring vulnerable people| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Multispectral imaging: Monitoring vulnerable people | | المؤلف : | Ali A. Al-Temeemy | | البريد الالكتروني : | ali.al-temeemy@liverpool.ac.uk | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | | | المستفيدين : | | | المستخلص : | This paper describes the development of a new healthcare monitoring system for vulnerable people which uses a visible image sensor and passive infrared sensors, in an unconventional manner, to monitor daily living activities. It based on a novel method, using chromatic methodology, to process spatially and temporally the incoming multispectral data from the visible and infrared parts of the spectrum, to overcome the impact of noisy environments, illumination changes and a dynamic background. An efficient chromatic descriptor is suggested to improve activity recognition of vulnerable people. The new monitoring system is robust to distortions associated with healthcare systems and its descriptor has an improved quality of description. System performance was evaluated using a series of experimental data, the results showing the efficacy of using both spatial and temporal domains of multispectral data to deal with events that disturb monitoring systems. The chromatic descriptor achieved a better performance in comparison to traditional methods when describing daily living activities. | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | | | الرابط : | https://doi.org/10.1016/j.ijleo.2018.11.042 |
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| | | Enhancement of Heat Transfer using Aluminum Oxide Nanofluid on Smooth and Finned Surfaces with COMSOL Multiphysics Simulation in Turbulent Flow| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Enhancement of Heat Transfer using Aluminum Oxide Nanofluid on Smooth and Finned Surfaces with COMSOL Multiphysics Simulation in Turbulent Flow | | المؤلف : | Hasan S. Majdi | | البريد الالكتروني : | Hasanshker1@gmail.com | | جهة انتساب المؤلف : | Department of Chemical Engineering and Petroleum Industries, Al-Mustaqbal University College, Iraq. | | المشاركين : | Hussein A. Alabdly, Muayad F. Hamad, Basim O. Hasan, Mustafa M. Hathal | | المستفيدين : | Ministry of Industry and Minerals ,Ministry of Oil | | المستخلص : | Both surface extension and nanofluidmethods were used to enhance the heat transfer in a double pipe heat exchanger under turbulent flow conditions. Aluminum oxide nanoparticles were used with different concentrations(0.6-3 g/l)in hot water to increase the heat transfer rate on smooth tube and circular fins tube for a range of Reynolds number424019790. The simulation was also performed to predict the heat transfer coefficient and temperature profile for selected conditions in which COMSOL Multiphysics is used. The experimental results revealed that the heat transfer enhancement by both circular fin and nanofluid exhibited an increasing trend with Reynolds number and nanofluid concentration. The conjoint effect of Al2O3of 3 g/l concentration and circular fin provided largest heat transfer enhancement of 53% for the highest Re investigated. Simulation results showed reasonable agreement with the experimental values of heat transfer coefficient. The simulation showed that the presence of nanofluid on finned surface influenced the temperature profile indicating the increased heat transfer rate | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | Heat Transfer; Enhancement; Nanofluid; Fin; Turbulent Flow. | | الرابط : | |
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| | | Optimization Design Methodology of Miniaturized Five-Band Antenna for RFID GSM and WiMAX Applications| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Optimization Design Methodology of Miniaturized Five-Band Antenna for RFID GSM and WiMAX Applications | | المؤلف : | Ayia A. S. A. Jabar | | البريد الالكتروني : | | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | Dhirgham K. Naji | | المستفيدين : | | | المستخلص : | This paper presents a novel design methodology for the design and optimization of a miniaturized multiband microstrip patch antenna (MPA) for wireless communication systems. Two design steps are used to do that. In the first step, an initial antenna is designed by a trial and error approach to operate nearly in the desired frequency bands, but the level of impedance matching (s 11 < −10 dB) for one or more bands is unsatisfactory, or some bands are uncovered by the antenna. The second design step is used after that to achieve optimized antenna by applying an optimization algorithm to effectively fine-tune the impedance matching of the initial deigned antenna to closely satisfy all the desired frequency bands. As an illustrative example, the proposed optimization methodology is used for designing a miniaturized multiband MPA suitable for operating at five different frequency bands, 915 MHz (RFID band), 1850 MHz (GSM band), (ISM-Industrial, Scientific, Medical), 2.45 and 5.8 GHz, and 3.5 GHz (WiMAX band). The proposed MPA used here is composed of two patch structures printed on both sides of an FR4 substrate occupying an overall size of just 28 × 28 mm 2. The final optimized antenna is fabricated, and its simulated and measured results are coinciding with each other validating the design principle. Moreover, simulation antenna performance parameters, surface current distribution, realized peak gain, and efficiency besides the radiation patterns at the desired frequency bands are obtained using CST MWS. | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | | | الرابط : | https://www.researchgate.net/publication/332030758_Optimization_Design_Methodology_of_Mi niaturized_Five-Band_Antenna_for_RFID_GSM_and_WiMAX_Applications |
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| | | Design of Miniaturized Quad-Band Dual-Arm Spiral Patch Antenna for RFID WLAN and WiMAX Applications| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Design of Miniaturized Quad-Band Dual-Arm Spiral Patch Antenna for RFID WLAN and WiMAX Applications | | المؤلف : | Ayia A. S. A. Jabar | | البريد الالكتروني : | | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | Dhirgham K. Naji | | المستفيدين : | | | المستخلص : | In this paper, a new design approach is presented for achieving a miniaturized quad-band microstrip patch antenna (MPA) suitable to be used for 915-MHz (UHF band), 2.45-and 5.8-GHz (ISM band), and 3.5-GHz (WiMAX band). The proposed antenna is called modified square spiral antenna (MSSA) which is composed of a modified dual-arm square spiral patch strip structure and a tapered-ground plane with coplanar wave-guide (CPW)-fed configuration to feed this antenna, all printed on the top side of an FR4 substrate. The proposed antenna is designed through intermediate systematic design steps of antennas starting from a conventional strip-fed rectangular MPA and ending by achieving MSSA. A CST Microwave Studio (CST MWS) is used to model the designed antenna, and simulation results, in terms of return loss (S 11), realized peak gain and efficiency, besides radiation patterns, are obtained. To validate the design concept, the antenna structure is fabricated, and the simulated and measured S 11 results nearly coincide with each other. The proposed antenna is characterized by miniaturized size of 28 × 28 mm 2 , and based on measured −10-dB S 11 result, MSSA has four bands, band 1: 915 MHz (872-929 MHz), band 2: 2.45-GHz (2395-2510 MHz), band 3: 3.5-GHz (3470-3550 MHz), and band 4: 5.8-GHz (5698-5900 MHz). | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | | | الرابط : | https://www.researchgate.net/publication/331938812_Design_of_miniaturized_quad-band_dual-arm_spiral_patch_antenna_for_RFID_WLAN_and_WiMAX_applications |
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| | | Configurable Beam-Steering Network for Phase Array Antennas- Part I: Proposed Configurable Photonic True Time Delay Line| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Configurable Beam-Steering Network for Phase Array Antennas- Part I: Proposed Configurable Photonic True Time Delay Line | | المؤلف : | Duaa Alyas Karim Aljaf | | البريد الالكتروني : | | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | Raad Sami Fyath | | المستفيدين : | | | المستخلص : | Beam-steering networks for phase array antennas (PAAs) have been successfully and efficiently implemented in the literature using photonic true time delay line (TTDL). The delay line has been designed according to the operating microwave frequency and number of radiating elements N of the PAA and cannot be adopted efficiently for other PAAs operating at different parameters values. Future wireless communication base stations will deal with PAAs having different values of and N and therefore, it is essential to design smart beam-steering networks. In this paper, a configurable photonic TTDL is proposed for PAA beam-steering network. The delay line consists of cascaded linearly chirped fiber Bragg gratings (LCFBGs) whose number is adopted according to the operating frequency, number of radiating elements, and steering angle. A parametric study of the used LCFBG is performed and the simulation results reveal that a FBG designed with 80 mm length and modified Gaussian apodization offers a 562 ps time delay difference across its reflectively spectrum bandwidth (4 nm). The scanning capabilities of PAAs incorporating this configurable photonic delay line is investigated and the results are given in the accompanying paper [1]. The simulation results reported here are obtained using "OptiGrating ver. 14-1" Software.Beam-steering networks for phase array antennas (PAAs) have been successfully and efficiently implemented in the literature using photonic true time delay line (TTDL). The delay line has been designed according to the operating microwave frequency and number of radiating elements N of the PAA and cannot be adopted efficiently for other PAAs operating at different parameters values. Future wireless communication base stations will deal with PAAs having different values of and N and therefore, it is essential to design smart beam-steering networks. In this paper, a configurable photonic TTDL is proposed for PAA beam-steering network. The delay line consists of cascaded linearly chirped fiber Bragg gratings (LCFBGs) whose number is adopted according to the operating frequency, number of radiating elements, and steering angle. A parametric study of the used LCFBG is performed and the simulation results reveal that a FBG designed with 80 mm length and modified Gaussian apodization offers a 562 ps time delay difference across its reflectively spectrum bandwidth (4 nm). The scanning capabilities of PAAs incorporating this configurable photonic delay line is investigated and the results are given in the accompanying paper [1]. The simulation results reported here are obtained using "OptiGrating ver. 14-1" Software. | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | Phase array antenna, Linearly chirped fiber Bragg grating, Microwave photonics, True time delay line | | الرابط : | DOI: 10.5923/j.ijnc.20190901.02 |
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| | | Synthesis and effect of silver nanoparticle as a delivery systems and anticancer agent| العنوان باللغة العربية : | | | العنوان باللغة الانكليزية : | Synthesis and effect of silver nanoparticle as a delivery systems and anticancer agent | | المؤلف : | Zainab Al-Haddad | | البريد الالكتروني : | zainabhaddad@yahoo.com | | جهة انتساب المؤلف : | Al-Nahrain University | | المشاركين : | | | المستفيدين : | | | المستخلص : | The field of nanotechnology meets the request for featuring new processes in the diagnosis and treatment of cancer. Traditional processes for cancer treatments had included chemotherapy, surgery, and radiation. Early diagnosis and treatment of cancer with these methods is still defying. The present study aims to innovative nanotechnology that can overcome multidrug resistance (MDR), raise drug localization and efficiency. This done by applying a nanotechnology technique to cancer cells which lead up to a new prospect for developing treatment methods on cancer cells. In this study silver nanoparticles (Ag NPs) were synthesized by chemical approach in range of different temperatures (100°C- 120°C- 140°C- 160°C- 180°C- 200°C), the characteristics of Ag NPs where measured by many methods which include: atomic force microscopy, UV-visible spectroscopy, zeta potential and raman spectroscopy techniques, the results of (Ag NP) tests show spherical nanoparticle with size range from (8-18nm) and polarization from (-49.3mv)-(-52.48mv) which give an indication of the stability of Ag NPs. The cytotoxicity of Ag NPs were tested in vitro by applying it on (L20B) cell lines first as anticancer agent, second as drug delivery system by combining the nanoparticle with chemotherapy (Methotrexate), third applied the chemotherapy (Methotrexate) on cell lines, the effect of Ag NPs and chemotherapy were measured by MTT assay to evaluate their drug delivery activity and anticancer activity, results of MTT assay test shows high inhibition rate of cell growth with Ag NPs as anticancer drug and Ag NP combined with chemotherapy as drug delivery system for cancer therapy. | | المستخلص باللغة العربية : | | | كلمات مفتاحية : | | | الرابط : | |
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