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Study of Type-B QPOs Observed in Black Hole X-Ray Binary Swift j1728.9-3613

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Research in Astronomy and Astrophysics 2024年第3期24卷 1-9页

作者： raj Kumar Astrophysical Sciences Division Bhabha Atomic Research CentreMumbai 400085India Homi Bhabha National Institute Mumbai 400094India

We report the detection of type-B quasi-periodic oscillation(QPO)of the black hole X-ray binary Swift j1728.9-3613 observed by NICER during the 2019 outburst.A type-B QPO was observed for the first two days and it disappeared as flux increased,but again appeared at∼7.70 Hz when flux was dramatically *** source was found in the soft intermediate state during these *** further studied the energy dependence of the *** found that QPO was observed only for a higher energy range implying that the origin of QPO is possibly due to the corona emitting higher energy photons by the inverse Compton *** variation of spectral parameters can be explained with the disk truncation *** fractional rms was found to be monotonically increased with *** phase lag spectrum followed the“U-shaped”*** rms and phase lag spectrum are modeled and explained with the single-component Comptonization model vkompthdk.

关键词： X-rays binaries-accretion-accretion disks-X-rays individual (Swift j1728.9-3613)

Analysis of vibration signal responses on pre induced tunnel defects in friction stir welding using wavelet transform and empirical mode decomposition

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Defence Technology（防务技术） 2019年第6期15卷 885-896页

作者： j.Rabi T.Balusamy R.raj jawahar Vinayaka Mission’s Kirupananda Variyar Engineering College SalemIndia Department of Mechanical Engineering Government College of EngineeringSalemIndia Department of Mechanical Engineering Dynamech Design SolutionsChennaiIndia

Among many condition-monitoring systems in welding operation,Defect identification is an important method to ensure the precision in finishing *** stir welding is a solid state welding process used to join two metals without the use of electrode at lower *** aim of this present work is to identify and localize the tunnel defect in aluminum alloy and measure the distance of the defect zone in the time domain of the vibration signal during Friction stir *** vibration signals are captured from the experiments and the burst in the vibration signal is focused in the analysis.A signal-processing scheme is proposed to filter the noise and to measure the dimensional parameters of the defect *** proposed technique consists of discrete wavelet transform(DWT),which is used to decompose the *** enveloping technique is applied on the decomposed zero padded *** continuous wavelet transform(CWT) has been implemented on detailed signal followed by a time marginal integration(TMI) of the CWT *** mode decomposition(EMD) is used to replace the detailing coefficients from DWT with Intrinsic Mode Function(IMF).Statistical parameters such as mean,kurtosis,S.D and crest factor have been extracted from the final filtered signal for validating the defect welds from the control defect free *** produced were found to be that kurtosis is 7.4402 for tunnel defect induced weld and 3.3862 for defect free *** the increase in kurtosis value predicts the defect zone impact in the *** measurement of the defect zone of the cut 1(voids) and cut 2(tunnel grooves) in correlation with the processed signal is found to produce a much redundant results with an error rate of 0.02.

关键词： welding friction alloy

Analysis of Bio-inspired Fishbone Based Corrugated Rib for Adaptive Camber Morphing

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journal of Bionic Engineering 2023年第3期20卷 1083-1102页

作者： R.jini raj j.Bruce Ralphin Rose A.Vasudevan Department of Mechanical Engineering Anna University Regional CampusTirunelveli627007India Saveetha School of Engineering SIMATSChennai600124India

Bioinspired active camber morphing is an innovative solution for the aerodynamic performance enhancement of flight vehicles such as Micro Aerial Vehicles(MAVs)and Unmanned Aerial Vehicles(UAVs).In the present article,a bio-inspired Fish Bone Active Camber(FishBAC)corrugated rib design concept with and without a spine for an Unmanned Aerial Vehicle(UAV)is *** wing model is composed of multiple corrugated ribs and a splitted spar for connecting each *** rib geometry is subjected to static structural analysis using ANSYS Finite Element Analysis(FEA)module under the unit load *** deformation modes are first extracted from the solution of the wind tunnel test and the elastically deformed NACA 4412 profile will be used to perform Fluid-Structure Interaction(FSI)studies as a partly coupled *** corrugated rib with spine design is a stable structure as inspired from nature species that can withstand elastic and inertial *** fluid dynamics(CFD)simulation is performed to compute the coefficient of lift(Cl),coefficient of drag(Cd)at different Angle of Attack(AoA)for a modified NACA 4412 airfoil and the pressure loads acting on the deformed shape is *** Cl obtained for the modified airfoil at lower AoA is about 60–80%higher and the maximum Cl(Clmax)is 62%higher than the baseline *** Cd of modified airfoil is reduced about 20%at the AoAα=3°as compared with the baseline *** proposed corrugated rib structure has been successfully 3D printed with Polylactic Acid plus(PLA+)material and the wind tunnel testing is done to validate the Cl,Cd values obtained through CFD simulations and the results are presented.

关键词： Bioinspired design Active morphing Fish bone Wind tunnel CFD

Enhancing prognostic accuracy in predicting rectal neuroendocrine neoplasms

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World journal of Gastroenterology 2024年第37期30卷 4087-4089页

作者： Renin Peter AA raj Abdulqadir j Nashwan Department of Medicine Aston Medical SchoolBirmingham B47ETUnited Kingdom Department of Nursing&Midwifery Research Hamad Medical CorporationDoha 3050Qatar

The recently published retrospective study introduces the GATIS score,a new predictive model for rectal neuroendocrine *** analyzing data from a large Chinese multicenter cohort,the study shows that the GATIS score,incor-porating tumor grade,T stage,tumor size,age,and prognostic nutritional index,demonstrates superior predictive power for overall survival and progression-free survival compared to traditional World Health Organization grade and tumor,nodes and metastases staging *** editorial aims to discuss the impor-tance of the GATIS score,its potential impact on clinical practice,and the strengths and limitations of the ***,it explores the significance,methodology,and clinical implications of these findings.

关键词： Rectal neuroendocrine neoplasm Nomogram Random forest Prognosis Overall survival Progression-free survival

CARBON MATERIALS FOR LITHIUM ION BATTERIES

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Chinese Chemical Letters 1996年第4期7卷 389-390页

作者： Ma, sh Li, j jing, XB Wang, FS ACAD SINICA CHANGCHUN INST APPL CHEMPOLYMER PHYS LABCHANGCHUN 130022PEOPLES R CHINA

The preliminary work indicated that passive film is the most important factor influencing cell performance of carbon anode, and the carbon and solvent used govern cell performance by forming the passive film of differ... 详细信息

关键词： ION CARBON MATERIALS FOR LITHIUM ION BATTERIES

Effects on the Surface Passive Film of Carbon Anode on Cell Behavior

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Chinese Chemical Letters 1997年第2期8卷 175-176页

作者： Ma, sh Li, j jing, XB Wang, FS ACAD SINICA CHANGCHUN INST APPL CHEMPOLYMER PHYS LABCHANGCHUN 130022PEOPLES R CHINA

The properties of the films formed in the electrolyte of PC/DME LiClO4 on two kinds of carbon materials were examined by cathodic polarization measurements. The result suggested that the films on both carbon electrode... 详细信息

关键词： DME Effects on the Surface Passive Film of Carbon Anode on Cell Behavior Cell

Comparison of two-and three-dimensional modeling of invert trap for sewer solid management

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Particuology 2008年第3期6卷 176-184页

作者： Tsewang Thinglas Deo raj Kaushal Civil Engineering Department IIT DelhiHauz KhasNew Delhi 110016India

In the present study, five different invert trap configurations （rectangular with and without lids on both sides; trapezoidal, trapezoidal with rectangular base and rectangular with trapezoidal base with lids on both sides） were simulated for both two-dimensional （2D） and three-dimensional （3D） flow conditions for three sediment types （sand, styrocell and plastic beads） at six flow rates （0.35, 0.70, 1.05, 1.35, 4.55 and 9.95 L/s） for each trap. Computational fluid dynamics （CFD）-based modeling using FLUENT software with Renormalization Group （RNG） k-e model along with discrete phase model （DPM） were used in the simulations. A hexagonal/tetrahedral and map-type non-uniform grid was chosen to discretize the entire computational domain and a control volume finite difference method was used to solve the governing equations. The flow rates selected in the present study cover the entire range of flow rate expected for dry weather and monsoon. The simulation is capable of differentiating between 2D and 3D modeling of particle trajectories, the effects of flow rate and trap geometry on flow patterns developed in the trap. The sediment retention ratio for 2D is higher than that for 3D modeling for all flow conditions, particle types and model geometry due to inclusion of lateral effects in 3D modeling. The invert trap having rectangular shape with trapezoidal base is found to be the most efficient configuration in both 2D and 3D modeling.

关键词： CFD modeling 2D 3D Invert trap Sediment trapping Urban drainage

The Possibility of Wax Formation in Gas Fields:a Case Study

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journal of Natural Gas Chemistry 2007年第3期16卷 293-300页

作者： Z.jeirani A.Lashanizadegan sh.Ayatollahi j.javanmardi School of Chemical and Petroleum Engineering Shiraz UniversityShirazIran School of Chemical Engineering Shiraz University of TechnologyShiraz.Iran

Natural gas production from a gas reservoir （Reservoir A） located in the south of Iran, presents solids deposition during processing because the condensate contains suspended and dissolved solids. Solids deposition occurs not only in the transportation lines from the wells to the separators but also in the various operating units of gas streams and condensate stream. In this study, the multisolid-phase model has been used to predict the wax precipitation from gas and gas condensate fluids. The properties of gas and liquid phases are described using the Soave-Redlich-Kwong （SRK） equation of state. The model is then used to predict the possibility of the wax formation in Reservoir A gas facilities, located at the south of Iran. Solid deposition which occurred in the various streams of that facility confirmed the calculated results. Finally, the wax appearance temperature （WAT）, the weight percent of wax formation and the effects of pressure and temperature on the wax formation were also predicted.

关键词： wax precipitation fluid phase equilibria multisolid model gas condensate

Three-dimensional computational fluid dynamics （volume of fluid） modelling coupled with a stochastic discrete phase model for the performance analysis of an invert trap experimentally validated using field sewer solids

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Particuology 2017年第4期15卷 98-111页

作者： Mohammad Mohsin Deo raj Kaushal Civil Engineering Department Indian Institute of Technology Delhi New Delhi India

Invert traps are used to trap sewer solids flowing into a sewer drainage system, The performance of the invert trap in an open rectangular channel was experimentally and numerically analysed using field sewer solids collected from a sewer drain. Experiments showed that the free water surface rises over the central opening （slot） of the invert trap, which reduces the velocity near the slot and allows more sediment to be trapped in comparison with the case for the fixed-lid model （assuming closed conduit flow with a shear-free top wall） used by earlier investigators. This phenomenon cannot be modelled using a closed conduit model as no extra space is provided for the fluctuation of the water surface, whereas this space is provided in the volume of fluid （VOF） model in the form of air space in ANSYS Fluent 14.0 software. Additionally, the zero atmospheric pressure at the free water surface cannot be modelled in a fixed-lid model. In the present study, experimental trap efflciencies of the invert trap using field sewer solids were fairly validated using a three-dimensional computational fluid dynamics model （VOF model） coupled with a stochastic discrete phase model. The flow field （i.e., velocities） predicted by the VOF model were compared with experimental velocities obtained employing particle image velocimetry. The water surface profile above the invert trap predicted by the VOF model was found to be in good agreement with the experimentally measured profile. The present study thus showed that the VOF model can be used with the stochastic discrete phase model to well predict the performance of invert traps.

关键词： Computational fluid dynamics mode Invert trap Sedimentation Trap efficiency Retention ratio Volume of fluid model