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In this article, we derive new modular relations on Ramanujan's product of theta-functions $\phi(q)$ and $f(-q^2)$, which is analogous to Ramanujan's remarkable product of theta-functions and their explicit evaluations.

Topic precise crawler is a special purpose web crawler, which downloads appropriate web pages analogous to a particular topic by measuring cosine similarity or semantic similarity score. The cosine based similarity measure displays inaccurate relevance score, if topic term does not directly occur in the web page. The semantic-based similarity measure provides the precise relevance score, even if the synonyms of the given topic occur in the web page. The unavailability of the topic in the ontology produces inaccurate relevance score by the semantic focused crawlers. This paper overcomes these glitches with a hybrid string-matching algorithm by combining the semantic similarity-based measure with the probabilistic similarity-based measure. The experimental results revealed that this algorithm increased the efficiency of the focused web crawlers and achieved better Harvest Rate (HR), Precision (P) and Irrelevance Ratio (IR) than the existing web focused crawlers achieve.

With the rapid increase in SARS-CoV-2 cases in children, a safe and effective vaccine for this population is urgently needed. The MMR (measles/mumps/rubella) vaccine has been one of the safest and most effective human vaccines used in infants and children since the 1960s. Here, we developed live attenuated recombinant mumps virus (rMuV)–based SARS-CoV-2 vaccine candidates using the MuV Jeryl Lynn (JL2) vaccine strain backbone. The soluble prefusion SARS-CoV-2 spike protein (preS) gene, stablized by two prolines (preS-2P) or six prolines (preS-6P), was inserted into the MuV genome at the P–M or F–SH gene junctions in the MuV genome. preS-6P was more efficiently expressed than preS-2P, and preS-6P expression from the P–M gene junction was more efficient than from the F–SH gene junction. In mice, the rMuV-preS-6P vaccine was more immunogenic than the rMuV-preS-2P vaccine, eliciting stronger neutralizing antibodies and mucosal immunity. Sera raised in response to the rMuV-preS-6P vaccine neutralized SARS-CoV-2 variants of concern, including the Delta variant equivalently. Intranasal and/or subcutaneous immunization of IFNAR1 −/− mice and golden Syrian hamsters with the rMuV-preS-6P vaccine induced high levels of neutralizing antibodies, mucosal immunoglobulin A antibody, and T cell immune responses, and were completely protected from challenge by both SARS-CoV-2 USA-WA1/2020 and Delta variants. Therefore, rMuV-preS-6P is a highly promising COVID-19 vaccine candidate, warranting further development as a tetravalent MMR vaccine, which may include protection against SARS-CoV-2.

The main objective of the paper is to prove some unified common fixed point theorems for a family of mappings under a minimal set of sufficient conditions. Our results subsume and improve a host of common fixed point theorems for contractive type mappings available in the literature of the metric fixed point theory. Simultaneously, we provide some new answers in a general framework to the problem posed by Rhoades (Contemp Math 72, 233-245, 1988) regarding the existence of a contractive definition which is strong enough to generate a fixed point, but which does not force the mapping to be continuous at the fixed point. Concrete examples are also given to illustrate the applicability of our proved results.

A roll cage is a structural framework of an All-Terrain Vehicle (ATV) which provides three-dimensional protection to the driver in case of sudden impact or rollover accidents and also to mount the various subsystems of the vehicle. Engineering world expects to satisfy the levied rules with substantiated quality of ATV which is compact in design, minimal members, lightweight, and high strength. The dynamically well-balanced ATV requires improvement of weldment strength and fatigue life of roll cage members to protect the driver and overcome terrain impacts. The objective of this work is to formulate a conceptual design using Solidworks and analysis by using Ansys for defined constraints like front, side, rear, and rollover impact on the roll cage of material of duplex S32205 steel with completion of weldment post-processing methods. The analysed set of data inputs experimentally made weld joint by Tungsten Inert Gas (TIG) welding under optimal process parametric condition and test on weldment is conducted for this study. This work involves post-processing method in which we accomplished good strength by utilizing the technique of shot peening where the small spherical shots were bombarded on the welded joints. As an outcome, we had achieved considerable decrease in residual compressive stresses on the weldment areas and increased its surface as well as fatigue strength. Before the strengthening techniques were put through, the weldment areas were spotted for inducting the shot peening method that enhances its strength further. To ensure the definiteness, test trials were done and value sets were taken for Finite Element Analysis (FEA) on optimal model with appropriate material. This proposed work provides the well-studied and optimal design approach on ATV roll cage to improve its acceleration by better weight reduction and enriched strength ratio for a long duration. Therefore, the weldment of roll cage which is shot peened has the better strength than that of unpeened sample.

A color fundus image is a photograph obtained using a fundus camera of the inner wall of the eyeball. In the image, doctors may see changes in the retinal vessels, which can be used to diagnose various dangerous disorders such as arteriosclerosis, some macular degeneration related to age, and glaucoma. To diagnose certain disorders as early as possible, automatic segmentation of retinal arteries is used to help the doctors. Also, it is a challenge for the medical community to analyze the image with the right procedure to diagnose the disorders with high accuracy. Furthermore, this will help the doctor to make the right decision on effective treatment. Hence, the authors have implemented an enhanced architecture called U-Net to segment retinal vessels in this paper. The proposed conventional U-Net permits using all the accessible spatial setting information by adding the multiscale input layer and a thick square to the conventional U-Net in terms of improving the accuracy level of image segmentation. It achieved 95.6% accuracy with a comparatively traditional U-Net model. Moreover, the segmentation results have proved that the proposed approach outperformed in detecting most complex low-contrast blood vessels even when they are very thin. The task of segmenting vessels in retinal images is known as retinal vessel segmentation. Blood vessel density can be assessed using dense pixel values. Data augmentation and analytics play a major role in building the true value of eye blood vessels for medical diagnosis. The proposed method is very promising in the automatic segmentation of retinal arteries.

Indian National Satellite System (INSAT) multi-spectral Rainfall Algorithm (IMSRA) is an operational rainfall estimation technique of INSAT-3D at Indian Meteorological Department (IMD) and Meteorological and Oceanographic Satellite Data Archival Centre (MOSDAC) since 2014. The IMSRA rain estimates are widely used for various application studies. This algorithm is based on an empirical power-law relation between infrared brightness temperature and surface rain rate. Based on further researches, some more innovative elements are recognized and incorporated into the parent IMSRA algorithm, termed as improved IMSRA. The present study evaluates the potential of the two versions of IMSRA algorithms for estimation of accumulated rainfall and its comparison with Global Precipitation Measurement (GPM) based IMERG rainfall during the 2018 summer monsoon period. Studies suggest satellite rainfall data at monthly and seasonal scales are better suited for hydrological and meteorological applications. Much studies are not done towards the evaluation and characterizations of the two versions of IMSRA algorithms at monthly and seasonal scales, and the present study focuses on such comparisons. The results indicate that the overestimation tendencies of the older version of the IMSRA algorithm are reduced in the improved version. The statistical analysis suggests that the updated version show a reduction ~25% error for the improved version in the seasonal estimation of rainfall.

This paper presents a novel control scheme for symmetric seven level Multi-Level DC link Inverter (MLDCL) as fed to RL load with reduced carrier strategy. The design of 7L-MLDCL can be done by taking three equal DC sources (assume PV with Boost converters) as level generator side and output phase voltage is taken at polarity generator side. All the traditional MLI like CHB, DCMLI, FCMLIs for generating ‘m’ level output, takes the switch count around 2(m-1) but the proposed inverter can reduce the switch count as (m+3). In reduced device count (RDC) MLIs, switch count reduction is one of important factor in the mean of each switch generally requires gate driver circuit, protection circuit and heat sink. The Simulation results of proposed inverter are validated through MATLAB/Simulink environment.

In the past decade, efforts have been focused on developing very fine, medium-carbon bainitic steels via the low-temperature (typically 300–400 °C) ausforming process, which not only enables shorter isothermal holding times for bainitic transformation at low temperatures, but also offers significantly improved strength. This paper describes static recrystallization (SRX) characteristics of austenite in four medium-carbon 2%Mn-1.3%Si-0.7%Cr steels with and without microalloying intended for the development of these steels. The stress-relaxation method on a Gleeble simulator resulted in recrystallization times over a wide range of temperatures, strains and strain rates. Also, the occurrence of precipitation was revealed. Powers of strain (−1.7 to −2.7) and strain rate (−0.21 to −0.28) as well as the apparent activation energies (225–269 kJ/mol) were in the ranges reported in the literature for C-Mn and microalloyed steels with lower Mn and Si contents. The new regression equations established for estimating times for 50% SRX revealed the retardation effects of microalloying and Mo addition showing reasonable fits with the experimental data, whereas the previous model suggested for ordinary microalloyed steels tended to predict clearly shorter times on average than the experimental values for the present coarse-grained steels. The Boratto equation to estimate the non-recrystallization temperature was successfully modified to include the effect of Mo alloying and high silicon concentrations.

An effort has been made to establish a relation between Zener–Hollomon parameter, flow stress and dynamic recrystallization (DRX). In this context, the plastic flow behavior of Ti + Nb stabilized interstitial free (IF) steel was investigated in a temperature range of 650–1100 °C and at constant true strain rates in the range 10−3–10 s−1, to a total true strain of 0.7. The flow stress curves can be categorized into two distinct types, i.e. with/without the presence of steady-state flow following peak stress behavior. A novel constitutive model comprising the strain effect on the activation energy of DRX and other material constants has been established to predict the constitutive flow behavior of the IF steel in both α and γ phase regions, separately. Predicted flow stress seems to correlate well with the experimental data both in γ and α phase regions with a high correlation coefficient (0.982 and 0.936, respectively) and low average absolute relative error (7 and 11%, respectively) showing excellent fitting. A detailed analysis of the flow stress, activation energy of DRX and stress exponent in accord with the modelled equations suggests that dislocation glide controlled by dislocation climb is the dominant mechanism for the DRX, as confirmed by the transmission electron microscopy analysis.

A new combination of factors enhancing the stabilization of austenite, including pre-existed austenite among quenched martensite, prior deformation, and partitioning at high temperatures is employed to create a multi-component refined microstructure in a medium Mn steel (Fe–4Mn–0.31C–2Ni–0.5Al–0.2Mo, wt.%). The microstructure evolution and phase fraction during the processing are systematically investigated using various characterization methods. The microstructure of the specimen after 0.4 strain deformation of 73% martensite–27% austenite at 250 °C and subsequent partition-annealing at 600 °C for 20 min was composed of several phases including tempered martensite, fresh martensite, pearlite, 10% of retained austenite (RA) and undissolved cementite. By increasing the annealing temperature, the pearlitic transformation was suppressed, whereas recrystallization of the deformed martensite and carbide dissolution occurred following annealing at 650 °C for 20 min resulting in an ultrafine-grained microstructure composed of equiaxed ferrite, 32% RA along with some fresh martensite during final cooling and few carbide precipitates. The results demonstrate that the combinatorial approach accelerated partitioning of alloying elements from martensite and carbides to largely pre-existing austenite is responsible for the improved austenite stabilization during intercritical annealing of the deformed dual-phase specimens. However, competitive processes are also enhanced so that the RA content is not increased by deformation.

A novel processing route comprising thermomechanical rolling followed by direct quenching and partitioning (DQ&P) was designed for developing tough, ductile, ultrahigh strength steels using 0.4 wt% carbon steels. A preliminary characterization of a laboratory-rolled, high-silicon DQ&P steel revealed an excellent combination of mechanical properties comprising high yield and tensile strengths (~1025 and ~2137 MPa, respectively), besides reasonable elongation (≈ 12%) and good impact toughness (T28J temperature ≈ −10 °C). The high mechanical properties are attributed to the formation of desired nanolath martensite-retained austenite (≈ 15%) structures. Features such as nano-twinned martensite, interlath austenite etc. were comprehensively characterized through high-resolution transmission electron microscopy. Attempts have been made to detect possible existence of metastable hexagonal omega phase within the boundaries of nano-twinned martensite and understand its nature of formation.

Quenching and partitioning (Q&P) treated steels are traditionally alloyed with silicon (Si), but its precise role on microstructural mechanisms occurring during partitioning is not thoroughly understood. In this study, dilatometric analysis has been combined with detailed microstructural characterization to unravel the competing mechanisms occurring during partitioning either in parallel or in succession. Three 0.4 wt.% carbon steels with varying Si contents were quenched to 150 °C for ∼20 % untransformed austenite, and partitioned for 10–1000 s in the temperature range 200–300 °C. The steel with low Si content (0.25 wt.%) exhibited substantial bainitic transformation during partitioning at 300 °C and only 4% retained austenite (RA) at room temperature (RT) even after 1000 s hold. In contrast, a high Si fraction (1.5 wt.%) enabled retention of ∼18 % austenite under similar conditions. While η-carbides precipitated within the martensite laths in the high-Si steel, cementite precipitated in the low-Si variant. Furthermore, carbide precipitation and growth were strongly suppressed by high Si content. Secondary martensite formation occurred from carbon-enriched austenite during final cooling, irrespective of Si-content. Results illustrate that Si retards austenite decomposition at higher partitioning temperatures but does not improve carbon partitioning at lower temperatures.

Background: Airborne dust plays a major part in the overall atmospheric pollution and motor vehicle emissions constitute the most significant source of ultra particle in urban environment. Traffic related air pollution is an occupational health hazard to individuals who work close to traffic. Objectives: To assess the impact of dust and traffic related air pollution on pulmonary functions of the exposed, non-smoking road side shopkeepers at busy traffic congested areas and to compare with age and sex matched non-smoking shop keepers from residential localities. Materials & Method: Cross-sectional study was conducted on 60 healthy adults aged 20-40years. 30 shopkeepers exposed to dust and traffic pollution residing nearer to busy road-crossings of Vijayapura city. Control group is 30 age and sex matched non-smoking, non-exposed healthy subjects who are working in shops away from the road traffic pollution. Anthropometric parameters, Physiological Parameters, Pulmonary function test were recorded in both control and subjects using standard techniques. Statistical analysis is done using SPSS. Results: We observed a significant reduction of FVC [subjects-2.63+0.40,control- 2.63+0.40,(p=0.03)] and FEV1 [subjects-2.47+0.59,control- 1.75+0.42,(p=0.000)] and an insignificant reduction of PEFR [subjects- 506.00+34.07,control-488.66+27.89,(p=0.610)] among the road side shopkeepers. Conclusion: The results of the study indicate the possibility of impaired lung function or obstructive lung disorders among the shopkeepers exposed to higher traffic pollution.