Journal Articles - Engineering - 2022
Permanent URI for this collection
Browse
Recent Submissions
1 - 5 of 5
-
PublicationA current sensor fault diagnosis method based on phase angle shift technique applying to induction motor drive( 2022)An improved method using the phase angle shift characteristic of the sine wave is proposed to diagnose the fault states of the current sensors in an induction motor drive. The induction motor drive (IMD) system applied in this study uses the field-oriented control (FOC) loop with integrated two current sensors and a speed encoder to control the rotor speed. The space vectors created from the phase angle shift technique are compared to the estimated current for the fault diagnosis algorithm. Various types of current sensor failures are investigated by MATLAB/Simulink software to check the effectiveness of the proposed method. The simulation results have proved the performance of the proposed method in enhancing the reliability and stability of the IMD system.
-
PublicationAnalytical Identification of Failure Modes and Design-Oriented Formulations in Hybrid FRP/Steel Reinforced Concrete Beams( 2022)This paper presents a simplified analytical method to identify six failure modes of hybrid fiber reinforced polymer (FRP)/ steel RC beams and to predict the corresponding moment capacity. A numerical method for estimating the flexural behavior of concrete beams reinforced with hybrid FRP/steel bars in terms of failure modes, steel yielding moment and moment capacity is also developed. To demonstrate the effectiveness of the proposed methods, the outcomes obtained from the analytical and numerical analysis were compared with experimental data tested by the authors and several other researchers. The comparison showed that these methods accurately identify the failure modes and accurately predict the moment capacity of hybrid FRP/steel RC beams with an average error of approximately 5%. Moreover, a parametric study was conducted to investigate the influence of the modulus of elasticity and tensile strength of FRP bars on the failure modes, steel yielding moment and moment capacity of hybrid FRP/steel reinforced concrete beams. The results indicated that the elasticity modulus of FRP rods considerably affects both the failure modes and the ultimate loading capacity of hybrid RC beams. The increase in the elastic modulus not only increases the ultimate moment but also changes the failure modes of the beams.
-
PublicationA second-order dynamical system for equilibrium problems( 2022)We consider a second-order dynamical system for solving equilibrium problems in Hilbert spaces. Under mild conditions, we prove existence and uniqueness of strong global solution of the proposed dynamical system. We establish the exponential convergence of trajectories under strong pseudo-monotonicity and Lipschitz-type conditions.We then investigate a discrete version of the second-order dynamical system, which leads to a fixed point-type algorithm with inertial effect and relaxation. The linear convergence of this algorithm is established under suitable conditions on parameters. Finally, some numerical experiments are reported confirming the theoretical results.
-
PublicationDy3+-doped P2O5–Al2O3–K2O–CaF2–LiF glasses: thermal, spectroluminescence and photometric properties( 2022)Fluorophosphate (PAKCLf: P2O5-Al2O3-K2O-CaF2-LiF) glasses with Dy3? concentration of 0.01, 0.05, 0.1, 0.5, 1.0, 2.0 and 3.0 mol% were fabricated by pouring the melt and sudden quenching process. The glass stability factor of 106 C was calculated by glass transition (563 C) and crystallite (669 C) temperatures. The energy bandgap (Eg) of Dy3?:PAKCLf glasses is calculated for (ahm)2 (direct) and (ahm)1/2 (indirect) allowed transitions. From optical absorption, the oscillator strength and spectroscopic intensity (X2,4,6) parameters by performing Judd–Ofelt calculations were estimated to evaluate the radiative transition properties of 4F9/2 level in Dy3? ions. The emission spectra consist of two intense bands in blue (485 nm: 4F9/2?6H15/2) and yellow (576 nm: 4F9/2?6H13/2) regions by stimulating at 349 nm. The decay curves demonstrate the non-exponential nature from 0.5 to 3.0 mol% of Dy3? and fitted well to the Inokuti–Hirayama model. The findings of stimulated emission cross-section (5.20 9 10–21 cm2), optical gain (29.59 9 10–25 cm2s), and quantum efficiency (97%) for Dy3?:PAKCLf glasses could be potentially utilized as optical devices. The photometric parameters like CIE colour coordinates and correlated colour temperatures (CCT:6300-6900 K) of Dy3?:PAKCLf glasses reveal the application of white light-emitting diodes.
-
PublicationThe Role of Manufacturing Industry in Economy: The Case of The Southern in Vietnam( 2022)The methodology is Path analysis model. The objective is to study how Index of Industrial Production (IIP) of five City-provinces in the Southern in Vietnam effect each other on these City-provinces’ GDP. How GDP of each City-province effects on Vietnam’s GDP. Results are Vietnam’s GDP is positively indirectly effected by IIPs of Ho Chi Minh, Binh Duong, Binh Phuoc, Tien Giang and is negatively affected by Tay Ninh’ s IIP. Besides, while GDP and IIP of Tay Ninh have negative general effect on GDP and IIP of other City-provinces and GDP of Vietnam, GDP and IIP of Binh Phuoc have the strongest general effect on GDP and IIP of other City-provinces and GDP of Vietnam. Next, GDP and IIP of Binh Duong have the second strongest general effect, GDP and IIP of Ho Chi Minh are the third strongest general effect, GDP and IIP of Tien Giang have the smallest general effect on GDP and IIP of other City-provinces and GDP of Vietnam. Therefore, we suggest that Tay Ninh should have a specific support mechanism. In particular, promoting development of science and tech in Ho Chi Minh to achieve the ""spillover effect"" to the other four City-provinces.