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Application of coupled XFEM-BCQO in the structural optimization of a circular tunnel lining subjected to a ground motion

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Frontiers of Structural and Civil Engineering 2019年第6期13卷 1495-1509页

作者： Nazim Abdul NARIMAN Ayad Mohammad RAMADAN Ilham Ibrahim MOHAMMAD Department of Civil Engineering Tishk International University-SulaimaniSulaimaniya 46001Iraq Mathematics Department-College of Science Sulaimani UniversitySulaimaniya 46001Iraq

A new structural optimization method of coupled extended finite element method and bound constrained quadratic optimization method(XFEM-BCQO)is adopted to quantify the optimum values of four design parameters for a circular tunnel lining when it is subjected to *** parameters are:tunnel lining thickness,tunnel diameter,tunnel lining concrete modulus of elasticity and tunnel lining concrete ***-Carlo sampling method is dedicated to construct the meta models so that to be used for the BCQO method using matlab *** simulations of the tensile damage in the tunnel lining due to a real earthquake in the literature are created for three design *** approach is used to show the cracks for the mentioned design *** results of the BCQO method for the maximum design case for the tunnel tensile damage was matching the results obtained from XFEM approach to a fair *** new coupled approach manifested a significant capability to predict the cracks and spalling of the tunnel lining concrete under the effects of dynamic earthquakes.

关键词： ovaling deformation monte carlo sampling XFEM-BCQO maximum principal stress

Medical waste management in iraq:a case study of Baghdad

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Waste Disposal and Sustainable Energy 2020年第4期2卷 329-335页

作者： Montazer K.Mensoor international Center for Training Research and Development(ICTRD)BaghdadIraq

There is a lack of information about medical waste management in *** study aims to monitor and evaluate the cur-rent situation of medical waste management in Baghdad as it represents the capital and the biggest populated city in *** 32%of hospitals are located in *** state-owned hospitals in Baghdad with the biggest bed capacity were *** study used structured interviews with staff in charge of waste management in the sampled hospitals to col-lect *** results showed that the generation rate of medical waste in the ten hospitals was 0.5 kg/(bed·day).The study also found that there were insufficient,ineffective,and improper isolation,collection,storing,processing,and safe disposal of medical wastes in the sampled public hospitals of *** study recommended that the iraqi Ministry of Health takes extensive and quick effective measures to better monitor and evaluate medical waste management and provide ongoing training to personnel responsible for waste management in the hospitals.

关键词： Medical waste Waste management Hospitals Baghdad iraq

Oxidation Properties in CO_2 of Inconel Alloy 600 Coated by Simultaneous Aluminizing-Chromizing Process

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Chinese Journal of Aeronautics 2007年第2期20卷 134-139页

作者： Ahmed Moosa Jalil Karim Ahmed Ali Hoobi The University of Technology Baghdad-Iraq Ministry of Labor and Social Affairs Baghdad-Iraq Ministry of Science and Technology Baghdad-Iraq

IN 600 alloy was coated with two different types of coatings, Cr-modified aluminide coating this is called aluminizing-chromizing and Y-doped chromium modified aluminide coating this is called aluminizing-chromizing-yttriumizing. Diffusion coating was carried at 1 050℃ for 8 h under Ar atmosphere by simultaneous aluminizing-chromizing process and by simultaneous aluminizing-chromizing- yttriumizing. Cyclic oxidation tests were conducted on the uncoated and on the coated Inconel 600 alloy in the temperature range 800- 1 000℃ in CO2 for 100 h at 10 h *** results showed that the oxidation kinetics for uncoated Inconel 600 alloy in CO2 is parabolic and the phases present are NiO, （Fe, Cr）2O3 , NiFe2O4 and NiCrO4. The oxidation kinetics for both coated systems in CO2 was found to be parabolic and the value ofkp for both coated systems were found to be lower than that for uncoated Inconel 600 alloy. Oxide phases that formed on coated systems are Al2O3 and NiCrO4. The role of yttrium can be attributed to its ability to improve the adherence of the oxide scale.

关键词： Inconel oxidation diffusion bonding aluminizing-chromizing Ni-superalloy

Analysis of stiffness and flexural strength of a reinforced concrete beam using an invented reinforcement system

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Frontiers of Structural and Civil Engineering 2021年第2期15卷 378-389页

作者： Nazim Abdul NARIMAN Martin HUSEK Ilham Ibrahim MOHAMMAD Kaywan Othman AHMED Diyako DILSHAD Ibrahim KHIDR Department of Civil Engineering Tishk International UniversitySulaimani46001Iraq Institute of Structural Mechanics Faculty of Civil EngineeringBrno University of TechnologyBrno331/95-60200Czech Republic

In this study,we conducted experimental tests on two specimens of reinforced concrete beams using a three-point bending test to optimize the flexure and stiffness *** first specimen is a reinforced concrete beam with an ordinary reinforcement,and the second specimen has an invented reinforcement system that consists of an ordinary reinforcement in addition to three additional bracings using steel bars and steel *** results of the flexure test were collected and analyzed,and the flexural strength,the rate of damage during bending,and the stiffness were *** element modeling was applied for both specimens using the LS-DYNA program,and the simulation results of the flexure test for the same outputs were *** results of the experimental tests showed that the flexural strength of the invented reinforcement system was significantly enhanced by 15.5%compared to the ordinary ***,the flexural cracks decreased to a significant extent,manifesting extremely small and narrow cracks in the flexure spread along the bottom face of the *** addition,the maximum deflection for the invented reinforced concrete beam decreased to 1/3 compared to that of an ordinary reinforced concrete *** results were verified through numerical simulations,which demonstrated excellent similarities between the flexural failure and the stiffness of the *** invented reinforcement system exhibited a high capability in boosting the flexure design and stiffness.

关键词： three-point flexure test softening stage flexural crack flexural strain

Enhancement of Electrical Performance of c-Si Solar Cells with New Texturization and Diffusion Process

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Journal of Chemistry and Chemical Engineering 2012年第7期6卷 638-645页

作者： Mohammad A1-Amin Ali Assi Microsol international LL fze Fujairah 4940 United Arab Emirates Department of Electrical and Electronic Engineering Lebanese International University Mazraa 146404 Beirut-Lebanon

Improving cell efficiency and increasing throughput in solar cell industry efforts were put on uniform texturization and optimum diffusion process. To reduce reflectivity, NaOH/KOH （sodium hydroxide/potassium hydroxide） and IPA （isopropyl alcohol） are widely used in standard alkaline texturization of mono c-Si （crystalline silicon）（〈100〉 crystal orientation） wafers, where IPA promotes formation of uniform pyramidal structure but leads to unstable process. In this work, carbohydrates have been investigated as an additive in etchant solution. Moreover uniform phosphorus diffusion process for B2B （back to back） diffusion （loading two wafers in one single slot of quartz boat） has been investigated with single and multiple temperature plateaus. Impact of pre-oxygen step on phosphorus diffusion is investigated in which number of inactive phosphorus at the PSG （phosphosilicate glass）-Si interface is reduced. A batch of 156 PSQ （pseudo square） mono c-Si solar cells with 18%-18.20% efficiency was fabricated which is -0.3% higher than the standard process. The EL （electroluminescence image）, reff （carrier effective life time）, Voc （open circuit voltage）, Isc （short circuit current）, Pvk （peak power） and r/ （efficiency） have been examined and compared with standard.

关键词： Sodium hydroxide potassium hydroxide isopropyl alcohol carbohydrate sheet resistance life time solar cell.

Preparation and photocatalytic property of Fe_(2)O_(3)/ZnO composites with superhydrophobicity

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international Journal of Minerals,Metallurgy and Materials 2021年第6期28卷 1072-1079页

作者： Muntadher I.Rahmah Raad S.Sabry Wisam J.Aziz Physics Department College of ScienceMustansiriyah UniversityBaghdad 10052Iraq

A facile approach was developed to construct Fe_(2)O_(3)-modified ZnO micro/nanostructures with excellent superhydrophobicity and photocatalytic *** effects of stearic acid(SA)and Fe_(2)O_(3) on the morphological characteristics,water contact angle(WCA),and photocatalytic degradation were *** results showed that WCA increased from 144°±2°to 154°±2°when the weight of SA increased from 5 to 20 mg because of the formation of a hierarchical or rough ***,Fe_(2)O_(3)-modified ZnO micro/nanostructure surfaces before and after SA treatment(20 mg)were chosen to evaluate the photodegradation of methylene blue(MB)dye under the support of visible *** degraded after 80 min of irradiation,and its photodegradation efficiencies were 91.5%at the superhydrophobic state and 92%at the hydrophilic *** improvement in photocatalytic activity at both states might be attributed to an increase in surface area and improvement in charge carrier separation.

关键词： nano composites stearic acid superhydrophobic photocatalytic self-cleaning

Drought trend analysis in a semi-arid area of iraq based on Normalized Difference Vegetation Index, Normalized Difference Water Index and Standardized Precipitation Index

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Journal of Arid Land 2021年第4期13卷 413-430页

作者： Ayad M F AL-QURAISHI Heman A GAZNAYEE Mattia CRESPI Department of Surveying and Geomatics Engineering Faculty of EngineeringTishk International UniversityErbil 44001Iraq Department of Forestry College of Agricultural Engineering SciencesSalahaddin UniversityErbil 44002Iraq Geodesy and Geomatics Division Department of CivilConstructional and Environmental EngineeringSapienza University of RomeRome 00185Italy Sapienza School for Advanced Studies Sapienza University of RomeRome 00185Italy

Drought was a severe recurring phenomenon in iraq over the past two decades due to climate change despite the fact that iraq has been one of the most water-rich countries in the Middle East in the *** iraqi Kurdistan Region(IKR)is located in the north of iraq,which has also suffered from extreme *** this study,the drought severity status in Sulaimaniyah Province,one of four provinces of the IKR,was investigated for the years from 1998 to ***,Landsat time series dataset,including 40 images,were downloaded and used in this *** Normalized Difference Vegetation Index(NDVI)and the Normalized Difference Water Index(NDWI)were utilized as spectral-based drought indices and the Standardized Precipitation Index(SPI)was employed as a meteorological-based drought index,to assess the drought severity and analyse the changes of vegetative cover and water *** study area experienced precipitation deficiency and severe drought in 1999,2000,2008,2009,and *** findings also revealed a drop in the vegetative cover by 33.3%in the year ***,the most significant shrinkage in water bodies was observed in the Lake Darbandikhan(LDK),which lost 40.5%of its total surface area in *** statistical analyses revealed that precipitation was significantly positively correlated with the SPI and the surface area of the LDK(correlation coefficients of 0.92 and 0.72,respectively).The relationship between SPI and NDVI-based vegetation cover was positive but not *** precipitation did not always correspond to vegetative drought;the delay of the effect of precipitation on NDVI was one year.

关键词： climate change drought Normalized Difference Vegetation Index(NDVI) Normalized Difference Water Index(NDWI) Standardized Precipitation Index(SPI) delay effect

Global sensitivity analysis of certain and uncertain factors for a circular tunnel under seismic action

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Frontiers of Structural and Civil Engineering 2019年第6期13卷 1289-1300页

作者： Nazim Abdul NARIMAN Raja Rizwan HUSSAIN Ilham Ibrahim MOHAMMAD Peyman KARAMPOUR Department of Civil Engineering Tishk International University SulaimaniSulaimaniya 46001Iraq Civil Engineering Department College of EngineeringKing Saud UniversityRiyadh 11421Saudi Arabia Department of Mechanical Engineering Faculty of EngineeringArak UniversityArak 38156-875Iran

There are many certain and uncertain design factors which have unrevealed rational effects on the generation of tensile damage and the stability of the circular tunnels during seismic *** this research paper,we have dedicated three certain and four uncertain design factors to quantify their rational effects using numerical simulations and the Sobol's sensitivity *** effects and interaction effects between the design factors have been determined supporting on variance-based global sensitivity *** results detected that the concrete modulus of elasticity for the tunnel lining has the greatest effect on the tensile damage generation in the tunnel lining during the seismic *** the other direction,the interactions between the concrete density and both of concrete modulus of elasticity and tunnel diameter have appreciable effects on the tensile ***,the tunnel diameter has the deciding effect on the stability of the tunnel *** the interaction between the tunnel diameter and concrete density has appreciable effect on the stability *** is worthy to mention that SoboFs sensitivity indices manifested strong efficiency in detecting the roles of each design factor in cooperation with the numerical simulations explaining the responses of the circular tunnel during seismic actions.

关键词： shear waves SoboFs sensitivity indices maximum principal stress maximum overall displacement tensile damage

Addressing the Issues and Developments Correlated with Envisaged 5G Mobile Technologies: Comprehensive Solutions

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Computers, Materials & Continua 2023年第11期77卷 2205-2223页

作者： Idrees Sarhan Kocher Energy Engineering Department Duhok Polytechnic UniversityDuhok42001Iraq

Fifth Generation(5G)communications are regarded as the cornerstone to household consumer experience improvements and smart manufacturing revolution from the standpoint of industries’*** is anticipated that Envisaged 5G(E5G)mobile technology would be operational in certain developed countries by *** Internet of Things(IoTs)will transform how humans live when combined with smart and integrated sensing devices,such as in-home sensing *** research is being carried out all over the world to produce a new technique that can be crucial in the success of the anticipated 5G mobile *** output,reduced latency,highly reliable,greater scalability,high performance,capacity,bandwidth efficiency,virtual open-air transmission,and efficient energy mobile wireless communications are all being investigated *** this work,a comprehensive path for addressing the difficulties and developments associated with 5G mobile technology is *** debate and description of a complete analysis of current situations,certain characteristics and prospective scenarios,important technologies,problems and advances,and spectrum allocation of envisioned 5G mobile technologies are ***,this paper analyzes the most notable elements of 5G mobile technology,such as Cognitive Radio(CR),flexibility,accessibility,and cloud-based service offers,which will assure 5G mobile technology’s dominance as the main protocol for international ***,this paper provides a method for integrating CR with current wireless communication systems,the necessity for further evolution of the E5G network,and the need for comprehensive consideration of architecture evolution and function enhancement to enhance the E5G mobile technologies.

关键词： E5G mobile technologies spectrum allocation pseudo outdoor communication key performance indicators cloudbased services efficient energy CR