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      • KCI등재

        Corrosion Behavior Optimization by Nanocoating Layer for Low Carbon Steel in Acid and Salt Media

        ( Ahmed S. Abbas ),( Bahaa Sami Mahdi ),( Haider H. Abbas ),( F. F. Sayyid ),( A. M. Mustafa ),( Iman Adnan Annon ),( Yasir Muhi Abdulsahib ),( A. M. Resen ),( M. M. Hanoon ),( Nareen Hafidh Obaeed ) 한국부식방식학회 2023 Corrosion Science and Technology Vol.22 No.1

        In this paper, a SiC nano electroless nickel plating layer with excellent corrosion resistance was fabricated using the Taguchi method. The electroless plated low carbon steel was subjected to tests to examine the influence of corrosive media, microhardness, and corrosion rate on the corrosion resistance of this alloy. Three different corrosive media (HCl, Na<sub>2</sub>SO<sub>4</sub>, and NaCl) at various temperatures (80, 90, and 100 ℃) were used, and at three different times (40, 80, and 120 min.) with a speed of stirring equal to 500 rpm. The results of microhardness were found from 134.276 HV to 278.578 HV at various conditions, while the corrosion rate results were obtained from 0.89643 mpy to 7.12571 mpy at different circumstances. Corrosion, and mechanical characteristics were explained using Taguchi design. Taguchi technique was used to account for all possible combinations of elements in order to conduct a complete study. Models that link the response and procedure parameters were developed using the results of these tests, and the analysis of variance was utilized to validate these models (ANOVA). For maximum efficiency, a function called “desirability” was applied to all responses at once.

      • KCI등재

        Load balancing in 5G heterogeneous networks based on automatic weight function

        Gures Emre,Shayea Ibraheem,Saad Sawsan Ali,Ergen Mustafa,El-Saleh Ayman A,Ahmed Nada M.O. Sid,Alnakhli Mohammad 한국통신학회 2023 ICT Express Vol.9 No.6

        Load balancing is a major challenge in heterogeneous networks (HetNets) consisting of 5G and 6G ultra-dense small cells with long-term evaluation advanced (LTE-A) networks. A key factor in achieving efficient load balancing during user mobility is creating appropriate optimisation for handover control parameters (HCP). This paper proposes a coordinated load balancing algorithm for LTE-A/fifth generation (5G) HetNets. The algorithm automatically optimises HCP settings for a given user based on three bounded functions (the signal-to-interference-plus-noise ratio (SINR) of the user equipment (UE), the number of physical resource blocks (PRBs) per UE and the UE’s speed) as well as their automatic weight levels. A two-step target cell determination strategy is implemented according to the cell load level and RSRP criteria, ensuring that users are handed over to low-loaded target cells. A new HO procedure that considers the pilot signal power is also proposed, which includes the number of PRBs per UE and the RSRP. Cells with freer PRBs are prioritised in user association to provide load balance and enhanced throughput. The proposed load balancing algorithm is compared with five other load balancing algorithms selected from the literature. The simulation results reveal that under various mobile speed scenarios, the proposed load balancing scheme enhances network performance in terms of load level, throughput, spectral efficiency and call dropping ratio (CDR).

      • KCI등재

        Improved Kerosene Quality with the Use of a Gamma Alumina Nanoparticles Supported Zinc Oxide Catalyst in a Digital Batch Baffled Reactor: Experiments and Process Modelling

        Jasim I. Humadi,Ghassan Hassan Abdul Razzaq,Luay Ahmed Khamees,Mustafa A. Ahmed,Liqaa I. Saeed 한국화학공학회 2023 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.61 No.2

        To create an environmentally sustainable fuel with a low sulfur concentration, requires alternative sulfur removal methods. During the course of this study, a high surface gamma alumina-supported ZnO nanocatalyst with a ZnO/-Al2O3 ratio of 12% was developed and tested for its ability to improve the activity of the oxidative desulfurization (ODS) process for the desulfurization of kerosene fuel. Scanning electron microscopy (SEM) and Brunauer-Emmett- Teller (BET) were used to characterize the produced nanocatalyst. In a digital batch baffled reactor (20~80 min), the effectiveness of the synthesized nanocatalyst was tested at different initial concentrations of dibenzothiophene (DBT) of 300~600 ppm, oxidation temperatures (25~70 ℃), and oxidation periods (0.5, 1, and 2 hours). The baffles included in the digital baffled batch reactor resist the swirling of the reaction mixture, thus facilitating mixing. The ODS procedure yielded the maximum DBT conversion (95.5%) at 70 ℃ with an 80-minute reaction time and an initial DBT level of 600 ppm. The most precise values of kinetic variables were subsequently determined using a mathematical modelling procedure for the ODS procedure. The average absolute error of the simulation findings was less than 5%, demonstrating a good degree of agreement with the experimental results acquired from all runs. The optimization of the operating conditions revealed that 99.1% of the DBT can be removed in 140 minutes.

      • KCI등재

        Flexural performance of cold-formed square CFST beams strengthened with internal stiffeners

        Ahmed W. Al-Zand,W.H. Wan Badaruzzaman,Mustafa M. Ali,Qahtan A. Hasan,Marwan S. Al-Shaikhli 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.34 No.1

        The tube outward local buckling of Concrete-Filled Steel Tube (CFST) beam under high compression stress is still considered a critical problem, especially for steel tubes with a slender section compared to semi-compact and compact sections. In this study, the flexural performance of stiffened slender cold-formed square tube beams filled with normal concrete was investigated. Fourteen (14) simply supported CFST specimens were tested under static bending loads, stiffened with different shapes and numbers of steel stiffeners that were provided at the inner sides of the tubes. Additional finite element (FE) CFST models were developed to further investigate the influence of using internal stiffeners with varied thickness. The results of tests and FE analyses indicated that the onset of local buckling, that occurs at the top half of the stiffened CFST beam’s cross-section at mid-span was substantially restricted to a smaller region. Generally, it was also observed that, due to increased steel area provided by the stiffeners, the bending capacity, flexural stiffness and energy absorption index of the stiffened beams were significantly improved. The average bending capacity and the initial flexural stiffness of the stiffened specimens for the various shapes, single stiffener situations have increased of about 25% and 39%, respectively. These improvements went up to 45% and 60%, for the double stiffeners situations. Moreover, the bending capacity and the flexural stiffness values obtained from the experimental tests and FE analyses validated well with the values computed from equations of the existing standards.

      • SCOPUSKCI등재

        Sterols and Sterol Glycosides from Cuscuta Reflexa

        E. Anis,G. Mustafa,S. Ahmed,Nisarullah,A. Malik,N. Afza,Y. Badar 한국생약학회 1999 Natural Product Sciences Vol.5 No.3

        A new natural product stigmast-5-en-3-O-β-D-glucopyranoside tetraacetate (1) along with known compounds stigmast-5-en-3-O-β-D-glucopyranoside (2), stigmast-5-en-3-yl-cetate (3) and β-sitosterol (4) have been isolated from the stems of Cuscuta reflexa. Their structures were elucidated on the basis of chemical and spectroscopic evidence.

      • KCI등재

        A New Commodity Distribution Approach Based on Asymmetric Traveler Salesman Using Ant Colony Algorithm

        Tua Halomoan Harahap,Ngakan Ketut Acwin Dwijendra,Sulieman Ibraheem Shelash Al-Hawary,A. Heri Iswanto,Noor Mohammed Ahmed,Yousra Mahdi Hasan,Saad Ghazi Talib,Purnima Chaudhary,Yasser Fakri Mustafa 대한산업공학회 2022 Industrial Engineeering & Management Systems Vol.21 No.3

        The traveling salesman problem is one of the most well-known hybrid optimization problems. It is one of the (NP-complete) problems that its various applications have theoretically and operationally attracted the attention of re-searchers. Given that the existing optimization methods to solve such problems include many variables and constraints and reduce their practical efficiency in solving problems with larger dimensions, we have seen the use of algorithms in recent decades. In this research, after determining a linear programming model for the asylum seeker problem with asymmetric distances and solving it in Lingo software, I used two ant cloning algorithms and a forbidden search algorithm to solve the problem in large dimensions. By adjusting the parameters of the two algorithms using the Taguchi method to prove the efficiency of the two algorithms, we compared their results by solving the linear programming model in small-dimensional problems. Then, to compare the results and execution time of the two algorithms, we solved the problem in medium and large dimensions.

      • KCI등재

        Numerical study of the cyclic behavior of steel plate shear wall systems (SPSWs) with differently shaped openings

        Mustafa M. Ali,S.A. Osman,O.A. Husam,Ahmed W. Al-Zand 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.26 No.3

        This paper presents the development of finite element (FE) models to simulate the behavior of diagonally stiffened steel plate shear wall systems (SPSWs) with differently shaped openings subjected to a cyclic load. This walling system has the potential to be used for shear elements that resist lateral loads in steel-framed buildings. A number of ½-scale one-story buildings that were un-stiffened, stiffened and stiffened with opening SPSWs are modeled and simulated using the finite element method based on experimental data from previous research. After validating the finite element (FE) models, the effects of infill plate thickness on the cyclic behavior of steel shear walls are investigated. Furthermore, triple diagonal stiffeners are added to the steel infill plates of the SPSWs, and the effects are studied. Moreover, the effects of a number of differently shaped openings applied to the infill plate are studied. The results indicate that the bearing capacity and shear resistance are affected positively by increasing the infill plate thickness and by adding triple diagonal stiffeners. In addition, the cyclic behavior of SPSWs is improved, even with an opening in the SPSWs.

      • KCI등재

        Corrosion Protection Effectiveness and Adsorption Performance of Schiff Base-Quinazoline on Mild Steel in HCl Environment

        Ahmed A. Alamiery,Firas F. Sayyid,Ali M. Mustafa,Mahdi M. Hanoon,Lina M. Shaker 한국부식방식학회 2022 Corrosion Science and Technology Vol.21 No.2

        Schiff base quinazoline derivative viz., 3-((2-hydroxy-3-methoxybenzylidene)amino)-2-methylquinazolin-4(3H)-one (SB-Q), was synthesized in this study. Its corrosion protection impact on mild steel (MS) in 1 Mhydrochloric acid solution was examined by performing weight loss measurements. The protective efficacyof SB-Q on MS in 1 M HCl was investigated based on its concentrations, immersion period, and immersion temperature. SB-Q was found to be an efficient inhibitor for the corrosion of MS. Its inhibitionefficiency was improved by increasing the concentration of SB-Q to an optimal concentration of 500 ppm. Its inhibition efficacy was 96.3% at 303K. Experimental findings revealed that its inhibition efficiency was increased with increasing immersion time, but decreased with an increase in temperature. The adsorption of SB-Q molecules was followed the Langmuir adsorption isotherm model. The adsorption of the examined inhibitor molecules on the surface of mild steel was studied by density functional theory (DFT). DFT investigation confirmed weight loss findings.

      • KCI등재

        Nonlocal nonlinear stability of higher-order porous beams via Chebyshev-Ritz method

        Ridha A. Ahmed,Nader M. Mustafa,Nadhim M. Faleh,Raad M. Fenjan 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.76 No.3

        Considering inverse cotangential shear strain function, the present paper studies nonlinear stability of nonlocal higherorder refined beams made of metal foams based on Chebyshev-Ritz method. Based on inverse cotangential beam model, it is feasible to incorporate shear deformations needless of shear correction factor. Metal foam is supposed to contain different distributions of pores across the beam thickness. Also, presented Chebyshev-Ritz method can provide a unified solution for considering various boundary conditions based on simply-supported and clamped edges. Nonlinear effects have been included based upon von-karman’s assumption and nonlinear elastic foundation. The buckling curves are shown to be affected by pore distribution, geometric imperfection of the beam, nonlocal scale factor, foundation and geometrical factors.

      • KCI등재

        Synthesis of nanomagnetite/copper oxide/potassium carrageenan nanocomposite for the adsorption and Photo-Fenton degradation of Safranin-O: kinetic and thermodynamic studies

        Asaad. F. Hassan,Laila M. Alshandoudi,Aya M. Awad,Ahmed A. Mustafa,Ghada Esmail 한국고분자학회 2023 Macromolecular Research Vol.31 No.7

        In the current study, a novel nanomaterial called nanomagnetite/copper oxide/potassium carrageenan nanocomposite (MKCO) was fabricated to include Fenton (nanomagnetite, NM) and Fenton-like reagent (copper oxide nanoparticles, NCO) in a matrix of potassium carrageenan biopolymer. The prepared solid materials were characterized by different physicochemical techniques, such as TGA, N2 adsorption/desorption, SEM, TEM, XRD, DRS, pHPZC, and FTIR. The prepared MKCO showed unique properties like higher specific surface area of 652.50 m2/g, pore radius of 1.19 nm, pHPZC equals 7.80, and the presence of different surface chemical functional groups. Under various application conditions, comparative experiments between Safranin-O dye (SO) adsorption and Photo-Fenton catalytic degradation were conducted. After 24 h, MKCO had a maximum adsorption capacity of 384.61 mg/g at 42 °C, while the Photo-Fenton oxidation process took only 10 min to totally decompose 93% of SO at 21 °C. Based on the higher values of correlation coefficients, Langmuir’s adsorption model is the best-fitted adsorption model for SO onto all the prepared solid materials. Studies on SO adsorption’s kinetics and thermodynamics show that it is physisorption and that it operates according to endothermic, spontaneous, and PFO model processes. While, PFO, endothermic, and non-spontaneous processes are satisfied by the catalytic decomposition of SO. After five application cycles, MKCO demonstrated good catalyst reusability with a 3.4% decrease in degrading efficiency. For lower contaminant concentrations and shorter application times, Photo-Fenton catalytic degradation of organic pollutants is more effective than adsorption.

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