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An improved co-training approach for document Sentiment classification
Jawad Khan(자와드 칸),Aftab Alam(아프타 발람),Muhammad Numan Khan(무함마드 누만 칸),Irfan Ullah(이르판 울라),Muhammad Umair(무하마드 우매르),Umair Qudus(구두스 우매르),Tariq Habib Afridi(타리크 하비브 아프리디),Sung Soo Park(박성수),Young-Koo Lee( 한국정보과학회 2020 한국정보과학회 학술발표논문집 Vol.2020 No.7
Concrete Made with Partial Substitutions of Wheat Straw Ash: A Review
Jawad Ahmad,Mohamed Moafak Arbili,Muwaffaq Alqurashi,Fadi Althoey,Ahmed Farouk Deifalla 한국콘크리트학회 2023 International Journal of Concrete Structures and M Vol.17 No.6
Many scientists are now focusing their attention on the utilization of valuable industrial or agricultural wastes as the primary raw material for the construction sector. These wastes, on the other hand, are affordable and readily accessible, making them ideal for commercial use while also contributing to the reduction of environmental degradation. Wheat straw ash (WTSA) is a kind of agricultural waste that has the potential to be utilized in concrete. Although many researchers are focused on utilization of WTSA in concrete. However, an updated review is required which provides easy access for the reader to get an idea about the benefits of WTSA in concrete. Therefore, this study provides a comprehensive review of the utilization of WTSA as a concrete ingredient. Physical and chemical compositions of WTSA, flowability, mechanical strength (compressive, flexure, tensile strength, and elastic modulus), and durability properties (permeability, carbonation, ultrasonic pulse velocity, alkali-silica reaction and chloride attacks) are the main aspects of this review. Results indicate that the performance of concrete improved with partial substitutions of cement with WTSA but simultaneously decreased the flowability of concrete. The optimum dose is important as higher dose results in decreased mechanical strength. The typical optimum dose ranges from 10 to 20% by weight of the binder. The performance of concrete in terms of durability was also improved but less research is carried out on the durability performance of concrete with WTSA. Additionally, despite WTSA's improvement in mechanical strength, concrete still exhibits lower tensile strain, which leads to brittle failure. Therefore, it was recommended that further study should be done to increase its tensile strength.
Novel Brushless Wound Rotor Synchronous Machine With Zero-Sequence Third-Harmonic Field Excitation
Jawad, Ghulam,Ali, Qasim,Lipo, Thomas A.,Kwon, Byung-Il IEEE 2016 IEEE transactions on magnetics Vol.52 No.7
<P>This paper introduces a novel topology for generating a spatial third-harmonic current component to excite the rotor field winding of a wound rotor synchronous machine to achieve brushless operation. In this topology, each of the three-phase windings on the stator is connected with a switch in parallel. In particular, two antiparallel thyristors are used to switch during positive and negative half cycles. Two windings are mounted on the rotor of the machine: 1) the harmonic winding and 2) the field winding. Zero-sequence currents are generated, when the switches are closed near zero crossing for a short time interval. Consecutive operation of the switches creates an additional spatial third-harmonic current pulsating in the stator winding. The number of poles of the stator winding and the field winding is the same (four-poles in this case) to intercept the torque generation component of the air-gap flux, whereas, the number of poles of the harmonic windings is adjusted (12-poles in this case) to intercept the harmonic component of the air-gap flux and develop voltage across the harmonic windings. Harmonic voltage is rectified through a rotating rectifier to feed dc current to the field windings. Results verify the proposed topology simulated by a 2-D finite-element method.</P>
Plasmonic effects and size relation of gold-platinum alloy nanoparticles
Jawad, Muhammad,Ali, Shazia,Waseem, Amir,Rabbani, Faiz,Amin, Bilal Ahmad Zafar,Bilal, Muhammad,Shaikh, Ahson J. Techno-Press 2019 Advances in nano research Vol.7 No.3
Plasmonic effects of gold and platinum alloy nanoparticles (Au-Pt NPs) and their comparison to size was studied. Various factors including ratios of gold and platinum salt, temperature, pH and time of addition of reducing agent were studied for their effect on particle size. The size of gold and platinum alloy nanoparticles increases with increasing concentration of Pt NPs. Temperature dependent synthesis of gold and platinum alloy nanoparticles shows decrease in size at higher temperature while at lower temperature agglomeration occurs. For pH dependent synthesis of Au-Pt nanoparticles, size was found to be increased by increase in pH from 4 to 10. Increasing the time of addition of reducing agent for synthesis of pure and gold-platinum alloy nanoparticles shows gradual increase in size as well as increase in heterogeneity of nanoparticles. The size and elemental analysis of Au-Pt nanoparticles were characterized by UV-Vis spectroscopy, XRD, SEM and EDX techniques.
Self-Compacting Concrete with Partially Substitution of Waste Marble: A Review
Jawad Ahmad,Zhiguang Zhou,Ahmed Farouk Deifalla 한국콘크리트학회 2023 International Journal of Concrete Structures and M Vol.17 No.4
Self-compacting concrete (SCC) is also seen as unsustainable since it uses a lot of natural resources. Recent researchers have focused on lowering construction costs and partially replacing cement with industrial waste. It is possible to effectively use various industrial wastes in concrete as cement or aggregates. Among these wastes, waste marble (WM) is a useful choice, and researchers have been interested in using WM in concrete for a couple of years. However, to pinpoint the advantages and recent advancements of research on WM as an ingredient of SCC, a comprehensive study is necessary. Therefore, the purpose of this study is to do a compressive evaluation of WM as an SCC ingredient. The review includes a general introduction to SCC and WM, the filling and passing capability of SCC, strength properties of SCC, durability, and microstructure analysis of SCC. According to the findings, WM improved the concrete strength and durability of SCC by up to 20% substitution due to micro-filling and pozzolanic reaction. Finally, the review also identifies research gaps for future investigations.
Modeling and simulation of planar SOFC to study the electrochemical properties
Jawad Hussain,Rashid Ali,Majid Niaz Akhtar,Mujtaba Hussain Jaffery,Imran Shakir,Rizwan Raza 한국물리학회 2020 Current Applied Physics Vol.20 No.5
In this paper, modeling and simulations are carried out using COMSOL Multiphysics. A three-dimensional model is developed for a planar intermediate temperature (IT) solid oxide fuel cell (SOFC). A parametric study has been carried out to analyze the performance of SOFC. Simulations reveal some promising features and enhanced performance of SOFC. It is shown that the maximum value of power (4–3.3) kW/m2 still remains higher with significant rise of temperature (600 °C–1000 °C), nearly 0.15 kW/m2 is the very small loss of power per 100 °C rise of temperature. Results have shown that the electrolytic current density is (6700–5500) A/m2 for peak value of power (4–3.3) kW/m2 with increase of temperature (600 °C–1000 °C). For model validation we have plotted a comparison of average current density.
Jawad Ahmed 한국고분자학회 2024 Macromolecular Research Vol.32 No.3
This study investigates the effects of electron beam (E-beam) irradiation on ethylene-vinyl acetate copolymer/ternary polyamide (EVA/tPA) blends with varying vinyl acetate (VA) content (19%, 28%, and 33%). The EVA/tPA blends were exposed to E-beam doses ranging from 50 to 300 kGy, with the addition of trimethylolpropane triacrylate (TMPTMA) and triallyl isocyanurate (TAIC) as crosslinking co-agents. SEM analysis and FTIR spectroscopy confirmed that increasing the VA content in the EVA/tPA blends significantly improved compatibility after E-beam irradiation, resulting in enhanced tensile strength, storage modulus, and surface smoothness. The EVA/tPA/TMPTMA blend with 33% VA content exhibited a remarkable 132% increase in tensile strength and a 212% increase in storage modulus due to enhanced crosslinking formation post-irradiation. However, irradiation led to a decrease in elongation at break and blend crystallinity. TMPTMA co-agents demonstrated superior compatibility compared to TAIC, further enhancing the overall properties of the EVA/tPA blends. In conclusion, E-beam irradiation is an effective technique for producing high-performance EVA/tPA blends by utilizing higher VA content and suitable co-agents. These improved materials hold great potential for various applications, particularly in the oil pipeline and automotive industries.