An Insight to the Dynamic Amplification Factor for Steel Truss Girder Bridge

S. Parida,S. Talukdar 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.4

The design of bridge is accomplished by magnifying static live load eff ect by a factor known as impact factor. In design codes of most of the countries, impact factor is provided as a function of bridge length or fundamental natural frequency. However, many studies recently conducted on bridge vehicle dynamics found other infl uencing parameters for the impact factor. In the present paper, the dynamic amplifi cation factor of the steel truss girder bridge has been found out taking bridge–vehicle dynamics using fi nite element method. An uncoupled iterative scheme interfacing the fi nite element software has been proposed to implement vehicle induced pavement force. The dynamic amplifi cation factors have been obtained for diff erent vital component of the steel truss bridge considering the variation of bridge span, vehicle speed, pavement roughness and inter spacing of successive vehicles on the bridge.

Studies of Structural, Microstructure, Dielectric and Optical Properties of Bismuth-Based Complex Perovskite Modified Bismuth Ferrite: BiFeO3 –(Bi0.5 Na0.25 K0.25 )(Ti0.5 Mn0.5 )O3 Ceramics

S. K. Sourav,S. K. Parida,R. N. P. Choudhary,Umakant Prasad 한국전기전자재료학회 2023 Transactions on Electrical and Electronic Material Vol.24 No.5

This communication describes a solid-state reaction prepared bismuth oxide and related complex compounds (BNKMT) of a chemical composition (1-x)BiFeO3-x(Bi0.5 Na0.25 K0.25 Ti0.5 Mn0.5 O3), where x = 0.15 and 0.20. Structural studies of the complex system show rhombohedral crystal symmetry (#R3c). The homogeneous distribution of the grains and grain boundaries throughout the sample surface clearly defined grain boundaries, which play a significant part in the conductivity mechanism, as revealed by the analysis of scanning electron microscopy micrographs and electrical properties. An energydispersive X-ray analysis spectrum was used to verify the processed materials’ purity and composition. According to the analysis of the FTIR-ATR spectrum, the prepared samples show stretching bands that correspond to their constituent elements. A dielectric investigation confirmed that the Maxwell–Wanger type of dielectric dispersion is present in the samples. Studies of impedance parameters as a function of temperature and frequency result in a negative temperature coefficient of resistance behavior. While ac conductivity research supports the presence of a thermally activated relaxation process in the materials. Analysis of electric modulus discloses a non-Debye type relaxation mechanism in the studied sample. Because the samples are semiconducting at high temperatures, semi-circular arcs have been seen in both the Nyquist and Cole–Cole plots. When compared to BNKTM 15%, BNKTM 20% has a bandgap energy of 5.9 eV, according to the analysis of UV visible spectra.

Studies on Structural, Dielectric, and Optical Properties of the Lanthanum Modifi ed BF-BNT Perovskite for the Thermistor and Photovoltaic Applications

S. K. Parida 한국전기전자재료학회 2022 Transactions on Electrical and Electronic Material Vol.23 No.6

The modified structure of BF-BNT (Bi0.5 La0.5 Fe) 0.25 (Bi0.5 Na0.5 Ti) 0.75 O3) single perovskite is prepared by a conventional solid-state reaction technique. The structural analysis suggests a tetragonal crystal with space group P4bm (JCPDS file No.01-070-4760). The average crystallite and lattice strains are 87.2 nm and 0.116% respectively. The dielectric study predicts negative temperature coefficient of resistance character while the presence of low dielectric loss makes the materials useful for energy storage devices. The analysis of the modulus study suggests the presence of a non-Debye type of relaxation process while a thermally activated relaxation process is confirmed from the study of ac conductivity. The presence of the depressed semicircular arcs in both Nyquist and Cole–Cole plots confi rms the semiconductor nature of the sample. The study of the Raman spectrum confirms the presence of all atomic vibrations. The UV visible study provides the energy bandgap of 1.67 eV, suitable for the different optoelectronic devices.

3D finite element analysis of stress distributions and strain energy release rates for adhesive bonded flat composite lap shear joints having pre-existing delaminations

S. K. Parida,A. K. Pradhan 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.2

The rate of propagation of embedded delamination in the strap adherend of lap shear joint (LSJ) made of carbon/epoxy composites hasbeen evaluated employing three-dimensional non-linear finite elements. The delamination has been presumed to pre-exist in the thin resinlayer between the first and second plies of the strap adherend. The inter-laminar peel and shear stress distributions have been studied indetails and are seen to be predominantly three-dimensional in nature. The components of strain energy release rate (SERR) correspondingto the opening, sliding and cross sliding modes of delamination are significantly different at the two fronts of the embedded delamination. The sequential release of multi-point constraint (MPC) finite elements in the vicinity of the delamination fronts enables to simulatethe growth of the delamination at either ends. This simulation procedure can be utilized effectively for evaluation of the status of thestructural integrity of the bonded joints.

Frequency–temperature response of CaBi4Ti4O15 ceramic prepared by soft chemical route: Impedance and modulus spectroscopy characterization

S.K. Rout,S. Parida,E. Sinha,P.K. Barhai,I.W. Kim 한국물리학회 2010 Current Applied Physics Vol.10 No.3

Polycrystalline CaBi4Ti4O15 ceramic has been prepared through a modified chemical reaction technique. Room temperature X-ray diffraction (XRD) analysis shows the formation of a single phase orthorhombic perovskite structure. Simultaneous analysis of the complex impedance (Z*), and electric modulus (M*)spectroscopy was carried in the temperature range of 100–850 ℃. The dielectric relaxation is found to be of non-Debye type. The Nyquist plot shows the negative temperature coefficient of resistance type behavior. Two different conduction mechanisms are may be due to: (a) the dielectric relaxation processes due to localized conduction associated with oxygen vacancy; and (b) the non-localized conduction corresponding to long range conductivity associated with extrinsic mechanisms fundamentally associated due to the chemical inhomogeneity caused due to the difference in the ionic environment of Ca2+ and Bi3+ and their sharing in the A site of perovskite and [Bi2O2]2+ slabs. Different conductivity components are recognized inside the grain: long range dc conductivity at low frequency region, a capacitive behavior at higher frequencies, and a universal power law behavior in an intermediate-frequency region where grain boundary contributions are neglected.

Microstructure, dielectric relaxation, optical, and ferroelectric studies of a lead-free double perovskite: BaLiFeMoO6

Mishra S.,Choudhary R. N. P.,Parida S. K. 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.2

In this article, the influence of co-substitution of alkali and transition metals at the Ba/Mo site of host BaMoO4 (inorganic Scheelite) is reported. A new lead-free double perovskite BaLiFeMoO6 (BLFMO) is synthesized using a conventional solid-state reaction route, having tetragonal crystal symmetry with an average crystallite size of 93.2 nm and strain of 0.115%. Grains are grown by sintering and distributed uniformly through well-defined grain boundaries as obtained from scanning electron microscopy (SEM). The purity and compositional analysis through energy-dispersive analysis X-ray spectroscopy (EDX) technique confirms the presence of constituent elements Ba, Li, Fe, Mo, and O. Raman study supports the substitution of Li/Fe atoms at Ba and Mo sites in the host matrix. Direct bandgap energy of 2.99 eV is calibrated using the ultraviolet–visible (UV–Vis) spectrum; may be suitable for photovoltaic applications. Maxwell–Wagner dielectric response, non-Debye relaxation, activation energy, and negative temperature coefficient resistance (NTCR) behavior are the outcomes of the synthesized sample characterized using dielectric, impedance, modulus, and conductivity plots in a wider spectrum of frequency (1 kHz–1 MHz) and temperatures (25–500 °C). The contribution of both grains and grain boundaries in the conduction mechanism has been investigated using Nyquist's fitting data calibrated from ZSIMPWIN software. A decrease in the magnitude of grain boundary resistance with a rise in temperature in fitted Nyquist's plot suggests the presence of semiconducting nature in the material. Analysis of leakage current density suggests that the nature of the conduction mechanism follows to the space charge limited current process. The study of temperature-dependent resistance supports BLFMO as a good candidate for NTC thermistor-related device applications. The study of polarization–electric field hysteresis loop suggests the possibility of the ferroelectric nature in the studied sample.

Structural, microstructural, dielectric, transport, and optical properties of modified bismuth ferrite

Sourav S. K.,Parida S. K.,Choudhary R. N. P.,Prasad Umakant 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.4

In this communication, the synthesis (solid-state reaction) and characterization (XRD, SEM, EDX, and IS) of the (1 −  x) BiFeO3 −  x(BiNaKTiMnO 3), (x = 0.05 and 0.1) ceramics were reported. The structural analysis suggests a rhombohedral crystal symmetry (#R3c) with an average crystallite size of 39.6 nm and micro-lattice strain of 0.000401 in x = 0.05 sample, whereas average crystallite size of 46.6 nm and lattice strain of 0.00133 in x = 0.1 sample, respectively. The growth and distribution of the grains and the position of grain boundaries were studied from a scanning electron microscope (SEM). The purity and compositional analysis of the prepared samples were checked from an energy-dispersive X-ray analysis (EDX) image. The study of the Fourier-transform infrared spectroscopy (FTIR) spectrum suggests the presence of a stretching band of the constituent elements in the modifi ed bismuth ferrite. The presence of the Maxwell–Wanger type of dispersion was confirmed by a dielectric study. The investigation of impedance as a function of temperature and frequency reveals the existence of a negative temperature coefficient of resistance (NTCR). A non-Debye kind of relaxation mechanism is revealed by electric modulus analysis; however, a thermally induced relaxation process is confi rmed by an ac conductivity study. The semi-circular arcs in the Nyquist and Cole–Cole plots indicate that the sample is semiconducting. BNKTM 5% has an energy bandgap of 2.9 eV, while BNKTM 10% has an energy bandgap of 2.7 eV, according to UV–visible spectra. The field-dependent hysteresis loop is analogous to the onset of ferroelectricity.

ON SEMILOCAL CONVERGENCE OF A MULTIPOINT THIRD ORDER METHOD WITH R-ORDER (2 + p) UNDER A MILD DIFFERENTIABILITY CONDITION

Parida, P.K.,Gupta, D.K.,Parhi, S.K. The Korean Society for Computational and Applied M 2013 Journal of applied mathematics & informatics Vol.31 No.3

The semilocal convergence of a third order iterative method used for solving nonlinear operator equations in Banach spaces is established by using recurrence relations under the assumption that the second Fr´echet derivative of the involved operator satisfies the ${\omega}$-continuity condition given by $||F^{\prime\prime}(x)-F^{\prime\prime}(y)||{\leq}{\omega}(||x-y||)$, $x,y{\in}{\Omega}$, where, ${\omega}(x)$ is a nondecreasing continuous real function for x > 0, such that ${\omega}(0){\geq}0$. This condition is milder than the usual Lipschitz/H$\ddot{o}$lder continuity condition on $F^{\prime\prime}$. A family of recurrence relations based on two constants depending on the involved operator is derived. An existence-uniqueness theorem is established to show that the R-order convergence of the method is (2+$p$), where $p{\in}(0,1]$. A priori error bounds for the method are also derived. Two numerical examples are worked out to demonstrate the efficacy of our approach and comparisons are elucidated with a known result.

ON SEMILOCAL CONVERGENCE OF A MULTIPOINT THIRD ORDER METHOD WITH R-ORDER (2 + p) UNDER A MILD DIFFERENTIABILITY CONDITION

P. Parida,D.K. Gupta,S.K. Parhi 한국전산응용수학회 2013 Journal of applied mathematics & informatics Vol.31 No.3

The semilocal convergence of a third order iterative methodused for solving nonlinear operator equations in Banach spaces is establishedby using recurrence relations under the assumption that the secondFr´echet derivative of the involved operator satisfies the !-continuity conditiongiven by ∥F′′(x) − F′′(y)∥ ≤ ω(∥x − y∥), x, y ∈ Ω, where, ω(x) is anondecreasing continuous real function for x > 0, such that ω(0) ≥ 0. Thiscondition is milder than the usual Lipschitz/H¨older continuity conditionon F′′. A family of recurrence relations based on two constants dependingon the involved operator is derived. An existence-uniqueness theorem isestablished to show that the R-order convergence of the method is (2+p),where p ∈ (0, 1]. A priori error bounds for the method are also derived. Two numerical examples are worked out to demonstrate the efficacy of ourapproach and comparisons are elucidated with a known result.

Schottky-type edge passivation of silicon solar cells

Choi, J.,Parida, B.,Palei, S.,Kim, K. North-Holland ; Elsevier Science Ltd 2017 Solar energy materials and solar cells Vol.159 No.-

We investigated Schottky-type edge passivation of Si solar cells using Ag nanodots and the enhancement of cell conversion efficiency by improving the fill factor. The threshold voltage for the termination of photocurrent is increased by about 0.13V compared to the reference sample without edge passivation. The cross-section of the pn junction depletion region forms an Ag/Si Schottky contact in the depletion layer of the space and the image charges with a width of about 28nm. However, the p- and n-electrodes form Ohmic contacts with a contact depletion width of less than 5nm for the carrier tunneling process. The edge Schottky contact reduces the carrier recombination and saturation current at the surrounding edge region and enhances the fill factor and the pn junction property with increased shunt resistance, indicating that metallic edge passivation is an important process for large-scale Si solar cell fabrication.