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This research paper explores the intricacies of heat and mass transfer in a vertical channel with immiscible fluids, focusing on the dynamics of two-fluid flows under the influence of variable viscosity, thermal conductivity, and thermal slip. The study further incorporates the effects of an internal heat source, adding complexity to the analysis of transfer processes. Mathematica's ND Solve software implements the Runge-Kutta sixth-order method, ensuring precise numerical simulations. A comprehensive analysis is performed on dimensionless velocity, angular velocity, temperature, and diffusion across relevant parameters. The results are visually represented to derive significant insights, including the impact of heat source intensity on the flow and transfer mechanisms. Bar charts illustrate critical components, such as shear stress, the Sherwood number, and the Nusselt number, enabling a clear comparison of heat and mass transfer rates along the channel wall. These findings contribute valuable knowledge for optimizing heat and mass transfer in various engineering applications.

Abstract Extreme El Niño events have outsized impacts and strongly contribute to the El Niño Southern Oscillation (ENSO) warm/cold phase asymmetries. There is currently no consensus on the respective importance of oceanic and atmospheric nonlinearities for those asymmetries. Here, we use atmospheric and oceanic general circulation models that reproduce ENSO asymmetries well to quantify the atmospheric nonlinearities contribution. The linear and nonlinear components of the wind stress response to Sea Surface Temperature (SST) anomalies are isolated using ensemble atmospheric experiments, and used to force oceanic experiments. The wind stress-SST nonlinearity is dominated by the deep atmospheric convective response to SST. This wind-stress nonlinearity contributes to ~ 40% of the peak amplitude of extreme El Niño events and ~ 55% of the prolonged eastern Pacific warming they generate until the following summer. This large contribution arises because nonlinearities consistently drive equatorial westerly anomalies, while the larger linear component is made less efficient by easterly anomalies in the western Pacific during fall and winter. Overall, wind-stress nonlinearities fully account for the eastern Pacific positive ENSO skewness. Our findings underscore the pivotal role of atmospheric nonlinearities in shaping extreme El Niño events and, more generally, ENSO asymmetry.

Introduction. When the working point of the indirect vector control is constant, the conventional speed and current controllers operate effectively. The operating point, however, is always shifting. In a closed-system situation, the inverter measured reference voltages show higher harmonics. As a result, the provided pulse is uneven and contains more harmonics, which enables the inverter to create an output voltage that is higher. Aim. A space vector modulation (SVM) technique is presented in this paper for type-2 neuro fuzzy systems. The inverter’s performance is compared to that of a neuro fuzzy type-1 system, a neuro fuzzy type-2 system, and classical SVM using MATLAB simulation and experimental validation. Methodology. It trains the input-output data pattern using a hybrid-learning algorithm that combines back-propagation and least squares techniques. Input and output data for the proposed technique include information on the rotation angle and change of rotation angle as input and output of produced duty ratios. A neuro fuzzy-controlled induction motor drive’s dynamic and steady-state performance is compared to that of the conventional SVM when using neuro fuzzy type-2 SVM the induction motor, performance metrics for current, torque, and speed are compared to those of neuro fuzzy type-1 and conventional SVM. Practical value. The performance of an induction motor created by simulation results are examined using the experimental validation of a dSPACE DS-1104. For various switching frequencies, the total harmonic distortion of line-line voltage using neuro fuzzy type-2, neuro fuzzy type-1, and conventional based SVMs are provided. The 3 hp induction motor in the lab is taken into consideration in the experimental validations.

In this paper, a novel technique using frequency selective surface (FSS) superstrate is proposed to increase the antenna gain. In addition to that, a combination of reactive impedance surfaces (RIS) is included to enhance the bandwidth. So, a conventional pentagon shape patch antenna is designed at 5.3 GHz. The frequency selective surface is designed as a 6×6 array of unit cell structures to operate around 5.3 GHz. Each unit cell consists of three metal conductive layers with substrates in between them. Reactive Impedance Surface is considered as an array size of 6×6 square patches embedded between two substrates. FSS is designed on Rogers 4003C and FR4 is used for RIS. The pentagon shape patch antenna is designed on RIS. A cavity created by the contribution of these layers acts like a fabry perot resonator which improves the gain and bandwidth simultaneously. The proposed antenna has an impedance bandwidth of 17.72% (4.93-5.89 GHz); this is about a 10 percent improvement over the impedance bandwidth of a conventional pentagon shape antenna and the axial ratio bandwidth is 2.4% (5.01-5.14 GHz). The designed antenna gain is around 12dBi; this is about a 9 dBi improvement over the gain of a conventional pentagon shape antenna.

A survey of environmental gamma radiation levels is attempted in the geographical site under construction to establish a petrochemical industry. The knowledge of natural background radiation is one of the significant steps in establishing the chemical industry. Some chemical operations such as chemical refinement may sometimes influence the natural radiation levels. The attempt of measurement of natural background gamma levels in the present paper is to establish the baseline data, which on further measurements will be useful to analyse the changes in natural background radiation levels at the time of operation of a chemical plant. The present investigation shows the activity levels of gamma radiation in the site under construction at 65 locations. The gamma levels are found to vary from 1459 μGyy-1 to 2765 μGyy-1 with the average of 2141±304 μGyy-1. It is to be noted from the study that the average gamma radiation levels at two sample locations, cement mixing point (2307 μGyy-1) and stone crushing point (2529 μGyy-1) have been elevated. The elevated radiation levels at the two sample locations can be attributed to the radioactive dust emitted in the process of crushing stones and cement mixing.

Cobalt-rich alloys of various compositions (Co33Fe33Ni33, Co40Fe40Ni20, Co50Fe25Ni25 and Co60Fe20Ni20) were synthesized from their respective precursor salts using a novel hydrazine reduction method. The synthesized nanosized powders were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM) techniques. XRD phase analysis results revealed that the Co33Fe33Ni33 alloy was formed with a pure FCC phase. Whereas, Co40Fe40Ni20, Co50Fe25Ni25 and Co60Fe20Ni20 alloys were composed of both FCC and BCC phases. The average particle size of the alloys was estimated to be in the range of 107–280 nm. The synthesized cobalt-rich alloys exhibited ferromagnetic properties at room temperature with a high saturation magnetization value up to 138 emu/g. The mixed phase Co40Fe40Ni20 alloy showed higher saturation magnetization and higher coercivity as compared to the other alloy compositions. In mixed phase alloys, the dominance of the BCC phase over the FCC phase seems to has resulted in the enhancement of the saturation magnetization value. The obtained results indicate that the hydrazine reduction method was effective in synthesizing cobalt-rich alloys with excellent soft magnetic properties. Keywords: Cobalt-rich alloys, Hydrazine reduction method, Electron microscopy, Magnetic properties

In modern secure Wireless Sensor Networks (WSN), the sensor-nodes need extra energy owing to secure transmission ofperceived information. So the energy-utilization of sensor-node should calculate while transfer the sensed-attributes securelyto network. In this experimentation, we are proposing a revised Low Energy Adaptive Clustering Hierarchy (LEACH)protocol as LEATCH along secure information transmission (privacy and node authentication) in various levels using Qualityof Protection Modeling Language (QoPML), which balance the Security-Energy trade-offs. This research experimentallyanalyzes the impact of data privacy, authentication operations on energy-utilization at sensor-node level while applying aLEACH & LEATCH. The obtained outcomes indicate the optimized LEATCH is outperforming correlated to the basic Leachwith respect to minimal energy-utilization, time efficiency and expands life-time of modern-secure-WSNs.

Geospatial technology is adopted in India through ‘Digital India’, for better governance and socio-economic benefits of common citizens. Remote sensing imageries and derived products are a direct input for geospatial data generation, monitoring resources and providing citizen services. As Indian Space Research Organisation (ISRO) is responsible for technology development, launch and data distribution of Indian remote sensing satellites, there is a conscious effort for partnership development with international space agencies and Indian industries to fulfil this requirement. Simultaneously ISRO’s co-operation with government departments for geo-spatial data generation and utilization is taken as a priority. This Paper presents the effort of ISRO for cooperation with International and national agencies as well as with government departments and policy makers. In this surge of utilization of geo-spatial techniques capacity building has become very relevant. A glimpse of geospatial education through government & academic institutes in India and E-learning is presented here with an emphasis of ISRO’s contribution.

Retrieval of mathematical text from data is a key predicament in present circumstances. To achieve this, we have considered three different algorithms viz., Sequence matcher, Levenshtein Distance and Fuzzy-Wuzzy. Two different variants of Fuzzy-Wuzzy are found applicable to this study out of four variants. Performance of these variants in retrieving mathematical texts, is calculated using efficiency measure, sensitivity analysis and time series exploration. Fuzzy-Wuzzy partial ratio algorithm scored better over the other variants on efficiency measure and sensitivity analysis.

Through this article a deep learning technique is proposed for the extraction and classification of mathematical keywords from textual documents. Extraction of math keywords from textual data is predominant problem as textual documents contain a culmination of mathematical symbols and literals from natural language such as alphabets and words. Separation of these textual words embedded in the mathematical formulae is a complex task. Our proposed technique solves this critical problem of extracting mathematical keywords from textual documents using techniques such as stemming,tokenization and clustering mathematical keywords based on a training set of mathematical keyword and formulae pairs. The performance of the proposed technique is measured using the metrics such as retrieval time, Sensitivity, Accuracy, FPR, FNR, and FDR are used for appraisal of the proposed technique.

Meghamalai landscape, southern Western Ghats was surveyed for anurans from March 2006 to January 2009. Including published data, a total of 35 species of anurans belonging to 19 genera and eight families have been reported from the area. This includes 23 (65.7%) species endemic to the Western Ghats. New locality records for four species namely, Fejervarya mudduraja, Raorchestes griet, R. ponmudi and Rhacophorus pseudomalabaricus were obtained. Several species recorded from the area are listed under various threat categories of IUCN Red List. Further studies are required to understand the ecological requirements of the anurans of the landscape.

Reports on the concurrence of mammals in the Meghamalai landscape were collated from published literature and also the data obtained from a recent study spanning over 18 months (June 2011-December 2012). Sixty-three species belonging to 24 families occur in the landscape, which include 24 globally threatened (one Critically Endangered; seven Endangered; 11 Vulnerable and five Near Threatened) species. Of the recorded species, four species are endemic to India and nine are endemic to the Western Ghats. The present study added five species, viz., Rusty-spotted Cat Prionailurus rubiginosus, Malabar Spiny Tree Mouse Platacanthomys lasiurus, Grizzled Giant Squirrel Ratufa macroura, Common Palm Civet Paradoxurus hermaphrodites and the Indian Grey Mongoose Herpestes edwardsii to the six decade old mammal list. But, 13 species reported by Hutton were not recorded during the study. Among them, occurrence of Malabar Civet Viverra civettina and Fishing Cat Prionailurus viverrinus in southern India remains unresolved. During our study, anthropogenic pressures such as conversion of natural habitats, encroachment, hunting, cattle grazing and tourism were observed to affect the distribution of mammals in the landscape.

Liver transplantation is the only existing modality for treating decompensated liver cirrhosis. Several factors, such as nonavailability of donors, combined with operative risks, complications associated with rejection, usage of immunosuppressive agents, and cost intensiveness, make this strategy available to only a few people. With a tremendous upsurge in the mortality rate of patients with liver disorders worldwide, there is a need to search for an alternative therapeutic tool that can combat the above limitations and serve as a supportive therapy in the management of liver diseases. Cell therapy using human fetal liver-derived stem cells can provide great potential to conservatively manage end-stage liver diseases. Therefore, the present investigation aimed to study and prove the safety and efficacy of human fetal liver-derived stem cell transplantation in patients with end-stage liver cirrhosis. Twenty-five patients with liver cirrhosis of different etiologies were infused with human fetal liver-derived stem cells (EpCAM+ve) labeled with Tc-HMPAO through hepatic artery. Our high throughput analysis using flow cytometry, RT-PCR, and cellular characterization exemplifies fetal liver cells with their high proliferation rate could be the best source for rejuvenating the diseased liver. Further, no episodes related to hepatic encephalopathy recurred in any of the subjects following hepatic stem cell transplantation. There was marked clinical improvement observed in terms of all clinical and biochemical parameters. Further, there was decrease in mean MELD score ( p < 0.01) observed in 6 months follow-up in all patients. Therapy using human fetal liver stem/progenitor cells offers a potentially supportive modality to organ transplantation in the management of liver diseases.

In this work, DC & RF magnetron sputtering and COMSOL multiphysics were used to simulate and deposit WO3 and WO3/Ag films, respectively. In the simulation cyclic voltammetry (CV) analysis was examined. The current density for the WO3/Ag films in comparison to the WO3 film was displayed higher. Based on the simulation findings, the experiment was done using DC & RF magnetron sputtering to deposit WO3 and WO3/Ag films. Scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–vis spectrometer, and electrochemical analyzer were used to examine the structural, morphological, EC, and optical characteristics of the deposited films. The SEM study revealed a smooth surface for WO3 films and WO3/Ag shows the grain of silver film. The XRD analysis of WO3 films shows the amorphous nature and in WO3/Ag films silver peaks were shown. The bandgap values were found to be 3.14 eV and 3.02 eV for WO3 and WO3/Ag films, respectively. Comparing the WO3/Ag film to the WO3 film, the cyclic voltammograms showed that the WO3/Ag film had the maximum current. In comparison to the WO3 film (30 cm2C−1), higher coloring efficiency values were noted for the WO3/Ag film (48 cm2C−1). For the WO3/Ag film, less time is needed for the coloring (tc = 2.2) and belching (tb = 1.8 s). It was clear that compared to a single-component WO3 film, the Ag-embedded WO3 composite system performed noticeably better electroactively and electrochemically. [ABSTRACT FROM AUTHOR]

The sol–gel auto-combustion method was used to prepared 5Zn0.4Cd0.1Fe2-xSmxO4 (x = 0.0, 0.02, 0.04, 0.06, and 0.08) doped with rare earth Sm3+. To adjust the structural, DC electrical resistivity, and magnetic characteristics of the spinel ferrites, rare earth Sm3+ was doped. As a result, using X-ray diffraction (XRD), field effect scanning electron microscopy (FESEM), Fourier transformation infrared spectroscopy (FTIR), two-probe technique, and vibrating sample magnetometer (VSM), respectively, researchers investigated the systematic impact of Sm3+ on the structural, morphological, DC resistivity, and magnetic studies. The synthesized materials' ability to form a single-phase nanostructure was confirmed by XRD investigation. Images captured by field effect scanning electron microscopy show that all samples exhibit spherical nanocrystalline activity. Spinel formation was verified using Fourier transform infrared spectroscopy (FTIR). NiZnCd ferrite's magnetic properties are examined to Sm3+ doping using vivid sample magnetometry spectra. Coercivity values and saturation magnetization decrease due to the increased Sm3+ doping. Data on saturation magnetization, coercivity, and remanence magnetization were obtained from the Sm3+ doping of NiZnCd micro ferrites. These results suggest that the device may find use in magnetic recording and memory applications. A two-probe approach is used to measure the DC electrical resistivity, which reveals the semiconducting nature. The carrier concentration and activation energy were found using data on DC electrical resistivity and were subsequently linked to Sm3+ replacement. The DC electrical resistivity testing of the prepared ferrite samples was conducted using a standard two-probe method. [ABSTRACT FROM AUTHOR]

In this study, Co–Cu–Zn–Cr nano ferrites with a composition of Co0.5Cu0.25Zn0.25Fe2-xCrxO4 (x = 0.0, 0.05, 0.1, 0.15, 0.2, and 0.25) are prepared by sol–gel auto combustion method. These doped nanocrystalline ferrites’ characteristics were examined using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and vibratory sample magnetometer (VSM). Such analytical characterizations were done for the structural and magnetic investigations. The crystallographic structure was identified using X-ray diffraction, which showed that a single-phase cubic spinel structure has been formed. According to the Debye–Scherrer equation, the synthesized samples’ average crystallite diameters ranged from 55.32 to 33.41 nm. Field emission scanning electron microscopy (FE-SEM) was used to study the surface morphology of the particles, revealing aggregated grains with a sponge-like structure. Functional groups were detected using Fourier transform infrared (FTIR) spectroscopy; peaks at about 393.21–582.71 cm−1 and 392.74–381.50 cm−1 indicated specific chemical properties. Magnetic characteristics at room temperature were investigated using a vibrating sample magnetometer (VSM), revealing some magnetic parameters. Hysteresis curves demonstrate reduced coercivity (263.98 to 126.62 Oe) and saturation magnetization (43.72 to 63.29 emu/g) upon metal ion replacement in the Co–Cu–Zn nano ferrites. [ABSTRACT FROM AUTHOR]