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Recent studies have shown that the Atlantic zonal mode (AZM) can significantly influence the Indian summer monsoon (ISM). In an earlier study, we proposed that AZM influence propagates in tropospheric temperature as Kelvin wave-like features to the east to reach the Indian Ocean and influences the monsoon by modulating the mid-tropospheric land-sea thermal gradient and thereby the seasonal mean flow. The changes thus induced in the mean flow were shown to affect the monsoon depressions in the Bay of Bengal and rainfall over India. In the present study, we use the Coupled Forecast System version 2, which is utilized for seasonal prediction of ISM in India, to examine how well the model simulates this AZM-monsoon link. In the sensitivity experiment, a warm AZM SST anomaly is added over the tropical Atlantic in the boreal summer and the ISM response is studied. We find that the model simulates the important aspects of the AZM-monsoon link. The model also simulates a known dynamics-based mechanism wherein a warm AZM SST anomaly produces a Matsuno-Gill type response, which in turn induces a sinking motion over India causing a reduction in rainfall. However, some finer details of these mechanisms are not simulated due to mean state biases in the tropical Atlantic in the model, a problem common to many coupled models. Our study highlights the need for the improvement of mean state of model in the tropical Atlantic to better capture the AZM-ISM relationship which will ultimately improve the monsoon forecasts issued using this model.

Al-Si based alloy matrix composites are now broadly utilized by the industrial sectors like automobile, structural, aerospace and more practical industrial applications due to its noncompetitive economy range, good mechanical properties and less density. In order to widen its applications, it is very significant to improve its mechanical and workability behavior. So, in this work, an effort has been taken to develop a ZnO microparticles (3, 4.5 & 6 %) reinforced with Al-Si-Mg (AA6061) alloy by stir casting route.Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction analysis (X-RD) were employed for characterization studies of the composites. Tensile and hardness of the composites are investigated, compared and analyzed its effects. Another novel finding of the work is determining the workability behavior of the prepared samples with aspect ratio of 1 by incremental compressive loading of 25 kN through cold upsetting technique. For all developed samples, true axial stress (σz), hoop stress (σө), hydrostatic stress (σm), effective stress (σeff), formability stress index (β) and stress ratio parameters [(σz/σeff), (σө/σeff), (σm/σeff)] were determined and the results are correlated with the axial strain (ez). The results clearly infers that increasing weight contributions of ZnO particles increase the mechanical properties, all the stresses and stress ratio parameters of the composites.

The performance of the solar water heater varies with respect to incident solar radiation, geographical location, and components of the solar water heater such as glazing, absorber material and sto...

The Seychelles-Chagos Thermocline Ridge (SCTR) is a key region which plays a major role in various regional climatic processes at all time scales. The vertical mixing at the base of mixed layer may be climatically important at this region, where a shallow thermocline and highly variable wind activity exists. In this study, we provide evidence of strong vertical mixing at the base of mixed layer and thermocline associated with near-inertial waves (NIWs) using the microstructure profiler time series data during boreal summer 2014. During the study, it was observed that the surface turbulent layer was mostly confined in the mixed layer with turbulent kinetic energy dissipation rate of the order of 10−6 Wkg−1. Elevated dissipation rate in the order of 10−7–10−6 Wkg−1 was also observed at the base of the mixed layer and thermocline (60–100 m) during the entire period of observation. The estimated vertical diffusive heat flux across the mixed layer base (100 Wm−2) was strong and a moderate downward flux (~ 30 Wm−2) was noticed in the thermocline region. The analysis showed that the strong NIW triggered by a strong wind event were responsible for the high dissipation rate at the base of mixed layer and at deeper depths. The higher-mode NIW create elevated vertical shear at the base the mixed layer, which leads to the enhanced mixing. The study also showed the possible role of internal tides on the subsurface mixing in the region. The NIW-induced mixing may have important role on the mixed layer heat balance in a climatically active SCTR.

In this study, a simulation-based optimization technique is employed to reduce nanoparticle deposition rate in a 90° square duct system. Nanoparticle deposition in the 90° bend pipe is highly influenced by bend radius, aspect ratio, airflow velocity, nanoparticle size, and mass flow rate. These factors are optimized for minimum deposition rate through Taguchi’s signal to noise ratio analysis and response surface methodology (RSM). L27 orthogonal array is employed in Taguchi's technique, and a central composite with 32 trials is used in the RSM technique. All the above cases are numerically simulated in computational fluid dynamics (CFD) tool using large eddy simulation (LES) and discrete phase model (DPM) for turbulence modeling. The minimum deposition rate of nanoparticles on the bend of a 90° square duct is predicted as 0.1389 through a confirmative test conducted for the best optimum values. The bend radius is the most influencing factor in the ANOVA analysis of deposition rate, and the other factors have shown the least influence on the deposition rate of nanoparticles.

The notion of complex valued metric spaces proved the common fixed point theorem that satisfies rational mapping of contraction. In the contraction mapping theory, several researchers demonstrated many fixed-point theorems, common fixed-point theorems and coupled fixed-point theorems by using complex valued metric spaces. The idea of b-metric spaces proved the fixed point theorem by the principle of contraction mapping. The notion of complex valued b-metric spaces, and this metric space was the generalization of complex valued metric spaces. They explained the fixed point theorem by using the rational contraction. In the metric spaces, we refer to this metric space as a quasi-metric space, the symmetric condition d(x, y) = d(y, x) is ignored. Metric space is a special kind of space that is quasi-metric. The Quasi metric spaces were discussed by many researchers. Banach introduced the theory of contraction mapping and proved the theorem of fixed points in metric spaces. We are now introducing the new notion of complex quasi b-metric spaces involving rational type contraction which proved the unique fixed point theorems with continuous as well as non-continuous functions. Illustrate this with example.

The diffusion brazing of Inconel 617 and AISI 321 stainless steel was carried out with a 50 μm thick AMS 4772 Ag interlayer at a constant brazing temperature of 750 °C under a variable holding time (30 & 60 min). The microstructure of the diffusion-brazed joints was studied in detail via the use of a scanning electron microscope and energy dispersive spectroscopy. The shear strength and fracture behavior of the joints were investigated. Void-free diffusion-brazed joints were obtained due to the capillarity effect of Ag and a more uniform reaction layer was obtained in the joint with a higher brazing/holding time. The joint with a prolonged brazing time of 60 min has the maximum shear strength of 322.9 MPa and an improvement of 26 % over the joint processed at 30 min. The predominant brittle (fracture) failure in the sample processed at 30 min brazing/holding time was responsible for its weak shear strength. At effective brazing/holding time, the use of the AMS4772 Ag interlayer has been effective in joining the IN617 and AISI 321 SS alloys.

This work aims to develop a mathematical model and predict the machining performance characteristics of electric discharge machining (EDM) process using response surface methodology (RSM) coupled with desirability function approach (DFA). The effect of various factors, such as electrode material, pulse current, pulse ON time and pulse OFF time were selected as input process parameters with an objective to maximize the material removal rate (MRR), minimize the surface roughness (SR) and electrode wear ratio (EWR). The machining was conducted on Al-Zn-Mg-Cu (AA7075) alloy composite reinforced with 10[Formula: see text]wt.% TiO2 particulates produced by stir casting route. The experimental work was planned as per L27 orthogonal array using design of experiments through RSM. Experimental results show that, pulse current and pulse ON time are the most significant factors for MRR and SR while electrode materials and pulse current have notable effect on EWR. Finally, multi-response optimization was performed to predict the EDM parameters by using DFA. The optimum combination of parameters were identified as electrode material (Br), pulse current (15 amps), pulse ON time (900[Formula: see text][Formula: see text]s) and pulse OFF time (30[Formula: see text][Formula: see text]s).

The Indian Ocean Observing System (IndOOS), established in 2006, is a multinational network of sustained oceanic measurements that underpin understanding and forecasting of weather and climate for the Indian Ocean region and beyond. Almost one-third of humanity lives around the Indian Ocean, many in countries dependent on fisheries and rain-fed agriculture that are vulnerable to climate variability and extremes. The Indian Ocean alone has absorbed a quarter of the global oceanic heat uptake over the last two decades and the fate of this heat and its impact on future change is unknown. Climate models project accelerating sea level rise, more frequent extremes in monsoon rainfall, and decreasing oceanic productivity. In view of these new scientific challenges, a 3-yr international review of the IndOOS by more than 60 scientific experts now highlights the need for an enhanced observing network that can better meet societal challenges, and provide more reliable forecasts. Here we present core findings from this review, including the need for 1) chemical, biological, and ecosystem measurements alongside physical parameters; 2) expansion into the western tropics to improve understanding of the monsoon circulation; 3) better-resolved upper ocean processes to improve understanding of air–sea coupling and yield better subseasonal to seasonal predictions; and 4) expansion into key coastal regions and the deep ocean to better constrain the basinwide energy budget. These goals will require new agreements and partnerships with and among Indian Ocean rim countries, creating opportunities for them to enhance their monitoring and forecasting capacity as part of IndOOS-2.

In this work, the natural fibres are reinforced into synthetic fibres along with natural fillers. The fibres are extracted from prosopis juliflora plant barks. The juliflora plants consumes ground ...

A good understanding of the general circulation features of the oceans, particularly of the coastal waters, and ability to predict the key oceanographic parameters with good accuracy and sufficient lead time are necessary for the safe conduct of maritime activities such as fishing, shipping, and offshore industries. Considering these requirements and buoyed by the advancements in the field of ocean modeling, data assimilation, and ocean observation networks along with the availability of the high-performance computational facility in India, Indian National Centre for Ocean Information Services has set up a “High-Resolution Operational Ocean Forecast and Reanalysis System” (HOOFS) with an aim to provide accurate ocean analysis and forecasts for the public, researchers, and other types of users like navigators and the Indian Coast Guard. Major components of HOOFS are (i) a suite of numerical ocean models configured for the Indian Ocean and the coastal waters using the Regional Ocean Modeling System (ROMS) for forecasting physical and biogeochemical state of the ocean and (ii) the data assimilation based on local ensemble transform Kalman filter that assimilates in situ and satellite observations in ROMS. Apart from the routine forecasts of key oceanographic parameters, a few important applications such as (i) Potential Fishing Zone forecasting system and (ii) Search and Rescue Aid Tool are also developed as part of the HOOFS project. The architecture of HOOFS, an account of the quality of ocean analysis and forecasts produced by it and important applications developed based on HOOFS are briefly discussed in this article.

An Electrical discharge machining (EDM) process is most essential in the machining of hard and complex geometrical material which is difficult to machine by conventional machining technique. The EDM process parameters namely electrode material, pulse current, pulse-on time and pulse-off time are significantly influence the machining performance characteristics, such as material removal rate (MRR) and tool wear rate (TWR). Hence, in the present study, the influence of EDM parameters on the MRR and TWR are examined during machining of Al-Fe-Si alloy (AA8011) filled with 15 wt.% ZrO2 composite fabricated through stir casting route. The experimental work was performed according to the L27 (34) orthogonal array using Taguchi design of experiments (DOE). A Taguchi method and Technique for order of preference by similarity to ideal solution(TOPSIS) has been used to investigate the multiple performance characteristics with an objective to maximize the MRR and minimize the TWR. Moreover, analysis of variance (ANOVA) has been employed to bring out the influence of the EDM parameters associated with each performance characteristics. Main effect plot shows that, the maximum MRR with minimum TWR are obtained by the optimum level of parameters are electrode material of EN-8, pulse current at 15amps, pulse-on time at 900 μs and pulse-off time at 60 μs. From ANOVA analysis, electrode material and pulse current are the most influencing parameters on the MRR and TWR. Finally, the confirmation experiment was conducted to verify the prediction of the results attained by the optimum EDM parameters combination.

Background: Medical data classification has become a hot research domain in data mining, but still it faces the increased classification accuracy issues. Methods/Statistical Analysis: Novel Hidden Markov Model based Support Vector Machine (HMM-SVM) is proposed to classify and predict Coronary Artery Disease (CAD). The features are extracted using HMM, and normalized using SVM. Feature Extraction assist the classification algorithm to get better results. HMM-SVM performs classification by extracting the features of Z-AlizadehSani dataset and finally selects the appropriate feature to perform classification. Findings: Z-AlizadehSani dataset holds 303 records with 4 different types of features, which are demographic, symptom and examination, ECG, and laboratory cum echo. For extracting these features and finding hidden information there exists no common algorithm. In HMM-SVM, HMM is applied to extract features by finding the hidden and previous stage values, and SVM is applied to perform classification on extracted features. To analyze the performance of HMM-SVM benchmark performance metrics are utilized. Discriminative performance results of internal validations are high in the task of binary classification (i.e., sensitivity- 98.2%; specificity-97.96%). False Positive Rate of HMM-SVM is entirely low (i.e.,1.87%) when comparing with previous algorithms. HMMSVM holds the classification accuracy as 98.02% and which is the better cum expected results towards the prediction of CAD. Novelty: Detailed analysis indicates HMM-SVM have better effects towards classifying and predicting CAD. Furthermore, care needs to be placed in adhering to ethical principles while utilizing the models that are automated. Future studies should make use of bio-inspired concepts to get even better results. Keywords: CAD; Classification; SVM; HMM; Markov

High strength Aluminum Alloy (AA8079) was synthesized through powder metallurgy (PM) technique and the effect of PM parameters on the properties was investigated based on Taguchi L9 orthogonal array experimental design. The compaction pressure, sintering temperature, and sintering time were chosen as input parameters and the properties such as hardness, compressive strength, and density were considered as responses. From signal to noise (SN) Ratio analysis, it is observed that the high level of compaction pressure (600 MPa), sintering temperature (600°C), and sintering time (3 h) is required to achieve the better compressive strength and hardness of alloy. From the ANOVA analysis, compaction pressure and sintering temperature were identified as highly contributing parameters to affect the properties of the PM AA8079. Further a confirmation test was conducted with the optimum parameter for validation of the Taguchi results. Microstructure analyses were conducted for all the nine samples to discuss the effect of parameters on the properties.

In the present study, the evaluation of FSW input parameters on output response ultimate tensile strength (UTS) of the friction stir welded AA6101-C11000 joint is in agreement. The response surface methodology (RSM) was adapted for generating the mathematical regression equation to predict the UTS and to develop the FSW parameters to attain the highest UTS of the FSW joints. The central composite design (CCD) method from RSM with five levels and three factors, i.e., tool rotational speed, feed rate, and tool offset used to conduct and minimize the number of tests. During FSW, base sheet cu (hard metal) was stationed on the advancing side (+1 mm, +1.68 mm tool offset) and the base sheet Al (soft metal) on the retreating side (−1 mm, −1.68 mm tool offset). The radiography studies were accomplished to inspect the internal flaws of the FSW joints (Al-Cu).The XRD and SEM investigation of the ruptured specimens during the tensile test to evaluate the IMCs phase anatomy and fracture analysis. The maximum UTS value measured during the experimental work was 142.69 MPa at 1000 rpm, 40 mm min−1, and −1.68 mm tool offset. The highest joint efficiency obtained was 82% compared with the AA6101 UTS value. RSM adapted for this work was 92% accurate and satisfactory.

The present research study investigates the Mechanical, Physical, and Tribological properties of powder metallurgy (PM) produced AA6063 alloy reinforced with silicon nitride (Si3N4) and copper nitrate (CuN2O6). Incorporation of Si3N4 & CuN2O6 reinforcement in matrix material ranged from 6 to 12 % Si3N4 in a 6-step interval and 2 to 6 %CuN2O6 in a two-step interval. The characterizations were made on the PM-produced specimens using OM, EDS, XRD, and Hardness. The reinforcement particles were uniformly distributed, which was attributed to a homogeneous mixer of matrix and reinforcements. The test findings show that as the reinforcing percentage of the ceramic and inorganic compound increases, properties such as hardness and density rise considerably and monolithically. The existence of phases such as Si3N4 and CuN2O6 reinforcement in the AA6063 matrix was ensured by X-ray diffraction. The hardness of AA6063/12%Si3N4/6%CuN2O6 increased by 88% over the base alloy due to a mismatch in thermal expansion between the Al matrix and reinforcement, which causes massive internal stress, causing the aluminium matrix to plastically deform to accommodate the reduced volume expansion of Si3N4 and CuN2O6 particles. The dry sliding wear test was determined using the Pin-on-Disc method, and the results show that the composite is more wear-resistant. An orthogonal array and analysis of variance were utilized to evaluate the solution, including parameters using the Taguchi robust design technique. The weight percentage of the Si3N4/CuN2O6 compound and the relationship between weight % of reinforcement and applied load had the most significant impact on composite wear resistance. The produced composite's wear morphology was studied using images from a scanning electron microscope and energy dispersive spectroscopy.

Despite its excellent qualities such as hardness, tensile, and yield strength, aluminum alloys are mostly used in aviation fins and car frames. However, wear resistance at maximum load is weak. This effort will now synthesize and investigate the tribological behavior of AA6063- (AlMg0.7Si-) AlN composites. The goal of this experiment is to determine the best wear rate and coefficient of friction for the AA6063-AlN with nanomagnesium composites developed. Weight percent, load (L), sliding velocity (SV), and sliding distance (SD) are the process factors studied, and the output responses are wear rate and friction coefficient. Bottom pouring type stir casting was used to create AA6063-AlN composites with various weight percentages. The various compositions are AA6063, AA6063-4 wt% AlN, AA6063-8 wt% AlN, and AA6063-12 wt% AlN. A pin-on-disc machine inspected the wear rate and friction coefficient of AA6063-AlN composites. Experimentation was done according to L16 orthogonal array (OA). Wear rate (WR) and coefficient of friction (COF) examinations were made to identify the optimum parameters to obtain minimum WR and COF for the AA6063-AlN composite via grey relational analysis (GRA). The contour plot analysis clear displays WR and COF with respect to wt% vs. L, wt% vs. SV and wt% vs. SD. The ANOVA outcomes revealed that wt% is the most vital parameter (85.55%) persuading WR and COF. The optimized parameters to achieve minor WR and COF was found as 12 wt% of AlN, L 20 N, SV 3 m/s, and SD 400 m. The worn surface was analyzed using scanning electron microscope and indicates that addition of AlN particles with matrix reduces the scratches. These articles offer a key for optimum parameters on wear rate and COF of AA6063-AlN composites via Taguchi grey relational analysis.

Aluminium matrix composites (AMCs) are broadly used to change the monolithic materials in aviation, automotive, and defense industries owing to their superior characteristics such as specific strength with light weight, greater hardness, good wear resistance, and better thermal properties. This novel work was aimed at estimating the specific wear rate (SWR) of zirconium dioxide- (ZrO2-) filled AA8011 (Al-Fe-Si alloy) matrix composites. A Taguchi method and response surface methodology (RSM) were used to find out the optimum range of control parameters on SWR of proposed composites. The stir casting technique was used to fabricate the composite specimens with varying proportions (5, 10, and 15 wt.%) of ZrO2 particle addition. The wear tests were performed as per L27 orthogonal design by using a pin-on-disk apparatus under dry conditions. For this test, four control parameters such as wt.% of ZrO2, load, disc velocity, and sliding distance each at three levels were selected. Based on the experimental results, 15 wt.% of ZrO2, 29.43 N of load, 0.94 m/s of disc velocity, and 1000 m of sliding distance provide the minimum SWR of the developed composite sample. ANOVA result revealed that the load (49.04%) was the primary dominant factor for affecting the SWR, followed by wt.% of ZrO2 content (29.24%), respectively. Moreover, scanning electron microscopy (SEM) analysis was performed to study the wear mechanism of worn-out surface of the composite test specimens.

This work made an attempt to optimize the powder metallurgy (PM) process parameters of ball-milled AA8079-B4C composites via Taguchi grey relational analysis to attain better mechanical properties. The process parameters are reinforcement weight percentage, compaction pressure, sintering temperature, and sintering time, and the output responses are micro Vickers hardness and compressive strength. The different reinforcement weight percentages are AA8079-x wt.%B4C ( X = 5 , 10, and 15 wt.%). The nanograin-refined green compacts were made at various compaction pressure 200 MPa, 300 MPa, and 400 MPa. The various sintering temperatures are 375°C, 475°C, and 575°C at different sintering times 1 h, 2 h, and 3 h. Taguchi L27 orthogonal array was utilized to examine the powder metallurgy process parameters. It could be understood from the results that higher reinforcement weight percentage, compaction pressure, and sintering temperature were determined as appropriate parameters to obtain maximum hardness and compressive strength.

Steam turbine blades are subjected to wear because of the continuous exposure to high pressure and temperature of the steam. Excessive wear in the blades adversely affects the power generation. Super alloys are commonly used to overcome these issues. Inconel 625 has been considered for analysis in the current work. To further enhance the wear resistance, Cr3C2 and Stellite were added. The wear behavior of Inconel 625 coated with Cr3C2 and Stellite at constant load and various temperatures are investigated. These coatings were deposited on the base metal by using the atmospheric plasma spray coating process. Fabricated sample pieces are characterized by Energy-dispersive X-ray spectroscopy (EDAX), Scanning Electron Microscope (SEM) and Vicker’s microhardness tester. Pin on disc tribometer has been used to study the friction and wear behaviour of the fabricated samples. Impact of the coatings with respect to wear are investigated with the help of SEM and EDAX. At various temperature settings, wear caused by the sliding of Inconel 625 coated with Cr3C2 and Stellite against the EN-8 steel disc are discussed. Temperature variations has affected both the coating’s removal and elemental composition. Stellite at room temperature and Cr3C2 at 400 °C significantly reduced the wear rate of Inconel 625 subjected to 20 N load condition.

In the satellite data era starting from 1979, the extent of Antarctic sea ice increased moderately for the first 37 years. However, the extent decreased to record low levels from 2016 to 2020, with the drop being greatest in the Weddell and Lazarev Seas of the Southern Ocean. An important question for the scientific fraternity and policymakers is to understand what ocean-atmospheric processes triggered such a rapid decline in sea ice. We employ in-situ, satellite, and atmospheric reanalysis data to examine the causative mechanism of anomalous sea ice variability in the Lazarev Sea at a time of ice growth in the annual cycle (March-April 2019), when a cargo ship was stuck in extensive ice cover and freed following the unusual decline in sea ice. High-resolution Sentinel-1 synthetic aperture radar captured a distinct view of the ship location and track within extensive ice cover of fast sea ice, dense pack ice, and icebergs in the Lazarev Sea on 27 March 2019. Subsequently, the sea ice cover declined and reached the fourth lowest extent in the entire satellite record during April 2019 which was 25.6% lower than the long-term mean value of 2.65 × 10

High saline and cold Antarctic Bottom Water (AABW) forms around the continental margin of Antarctica that ventilates into the global ocean. To study the recent changes in AABW, we have analyzed the in situ observations collected from Indian Ocean expeditions to the Southern Ocean during 2010, 2011, 2017, 2018, and 2020. A comprehensive analysis of these observations indicated recent freshening, warming, and contraction in the layer thickness of the AABW. Even though the AABW depicted inter-annual variability, it changed to moderately fresher and lighter water mass at the end of the recent decade. The characteristics of AABW exhibited a contraction in its layer thickness (∼50–120 m) during recent years. The water mass showed its freshening (∼0.002) and warming (∼0.04°C) tendency from 2018 to 2020. The recent warming (∼0.3°C) of Circumpolar Deep Water (CDW) near the Prydz Bay suggests enhanced melting of ice shelves. It is hypothesized that the combined influences of onshore intrusion of warm CDW, upper ocean warming, sea ice decline, wind forcing, polynya, and calving events possibly caused the freshening and reduction in the thickness of AABW. The continued changes in the ocean-atmospheric environmental conditions and the subsequent changes in the bottom water characteristics likely influence the global climate, overturning circulation, and the biogeochemical cycle.

In recent days, natural fibers are extremely influential in numerous applications such as automobile body building, boat construction, civil structure, and packing goods. Intensification of the properties of natural fibers is achieved by blending different natural fibers with resin in a proper mixing ratio. This investigation aims to synthesize a hybrid polymer matrix composite with the use of natural fibers of flax and loops of hemp in the epoxy matrix. The synthesized composites were characterized in terms of tribological and mechanical properties. The Taguchi L16 orthogonal array is employed in the preparation of composite samples as well as analysis and optimization of the synthesis parameters. The optimization of compression molding process parameters has enhanced the results of this investigation. The parameters chosen are percentage of reinforcement (20%, 30%, 40%, and 50%), molding temperature (150 °C, 160 °C, 170 °C, and 180 °C), molding pressure (1 MPa, 2 MPa, 3 MPa, and 4 MPa), and curing time (20 min, 25 min, 30 min, and 35 min). From the analysis, it was observed that the percentage of reinforcement is contributing more to altering the fatigue strength, and the curing time is influenced in the impact and wear analysis.

In this work, copper (Cu) matrix composite reinforced with titanium carbide (TiC) was fabricated by powder metallurgy (PM) method with the varying TiC content from 0% to 12% by weight in the step of 4%. The required weight percentage of powders was milled in an indigenously developed ball milling setup. Green compacts were made using a computer-controlled hydraulic press (400 kN) and sintered in a muffle furnace at a temperature of 950°C. Scanning electron microscope (SEM) was used to analyze the distribution of TiC particles in Cu matrix in as-sintered conditions. X-ray diffraction (XRD) analysis resulted in the existence of respective phases in the produced composites. The structural characteristics such as stress, strain, dislocation density, and grain size of the milled composites were evaluated. Cold upsetting was conducted for the sintered composites at room temperature to evaluate the axial (

Amongst the welding techniques the laser beam welding process seems precise and less heat affected with high intensity. This investigation is focused to study the feasibility and to find optimal welding parameters for the AISI316L and monel400 dissimilar welding. The selected materials are widely applicable in the field of marine, heat exchangers and chemical industries for storage tanks. The Nd-Yag laser welding machine is used for this dissimilar welding and the process parameters like laser wire diameter, power and frequency are investigated. The weld quality is analyzed by the result of ultimate tensile strength, hardness and metallographic observation using the universal testing machine, Vickers hardness tester and optical microscope. The Taguchi L9 orthogonal array is used to fix the process parameters and the regression equations are obtained from the design expert shows the ANOVA model is significant. From the result it is inferred that the most influencing parameter observed is laser wire diameter for both the ultimate tensile strength and hardness. This experimentation of dissimilar welding gives betterment of welding industries for fixing the optimal process parameters.

The scrutiny involves the examination of the Automated Fibre Placement (AFP) of thermosetting and thermoplastic materials with a detailed explanation and the overview of the AFP process and its applications. The principal aim of the paper is to endorse the effective, expeditious nature, multiple stiffened composite layer production of the Automated Fibre Placement process using thermosetting and thermoplastic materials. The key process parameters such as the delivery, pressure application, heating of the fibre, compact structure of the fibre placements are discussed in flourishing nature. The Impact of innovation of the earlier stages which lead to the outburst of the AFP is adduced in the paper. Additionally, thermoplastic and thermosetting applications in the AFP which lead to the remarkable cutting edge technological milestones in multiple fields is acquainted with the article.

The availability of potable water is exhausting nowadays due to tremendous reduction and pollution created by human being. Hence desalination using single slope solar still paves an economic and efficient way to generate clean drinking water from brackish water, in comparing to various contamination removing processes. Solar desalination method using still is uncommon, as it production rate and thermal performance is low. Various researchers have carried out different experimental modifications and inclusions of different nanomaterials in the base fluid of the solar still to enhance the distillate. This present review is done to evaluate and understand the influence of adding various nanomaterials in the solar still base fluid towards the production rate and heat transfer characteristics. This survey is adequate to enhance the knowledge level of the future researchers in this field and also assist numerous researchers in selecting the significant process and modification that elevate the production rate of the single slope (SS) solar still.

This work studies the moisture absorption characteristics of jute reinforced, waste plastic particulates filled polymer composites. To minimize the percolation of the water, the voids must be minimized or eliminated or it has to be filled with some external fillers. The specimens were produced at varying weight ratios by varying the amount of reinforcement and fillers. The process parameters such as weight percentage of plastic particulates, jute reinforcement and type of chemical treatment for jute fibers were established by Taguchi method. The influencing parameters on moisture absorption characteristics was optimized. The results were optimized to determine the ratio in which the composite possess maximum water resistance.

The energy absorbing capacity of the safety helmet mainly depends on the materials used for the fabrication of the helmet. The researchers are working vigorously in the material with low weight and excellent mechanical properties that a helmet should have. An attempt has been carried out to light the various materials utilized for the manufacturing of safety helmet. Hybrid fibres are being developed with different combinations to replace the existing materials for the fabrication of the helmet. In this study, a review of the advanced materials developed as an alternative for conventional materials for the Industrial Safety Helmet is done.

The unique material, Graphene has emerged into the field of engineering to create a material revolution. This review paper gives an outlook about Graphene - its production, applications, broad scopes in every field like additive manufacturing, electronics, biomedical, textile, aerospace, and printing technologies. Graphene is an allotrope of carbon which is a two-dimensional atomic crystal structure made up of carbon atoms arranged in the hexagonal lattice. Graphene exhibits a plane of sp2-bonded atoms. Graphene is layered one above the other with an interplanar spacing to form graphite. The production methods, current research and recent progress in implementing for its vast commercial usage, advancement in research were summarized and also the future prospects of graphene in the replacement of silicon in electrical systems. Graphite can explore in diverse applications such as composition structure, bio medical application, membranes and energy storage devices.

Titanium is the most emerging usable metal in aerospace engineering, dental prosthodontics and even in nuclear plants. The welding parameter plays a major role in the welding process which reflects in microstructural changes in the Fusion Zone (FZ) and Heat Affecting Zone (HAZ). This paper examines the different types of welding processes in pure titanium such as plasma arc welding, tungsten inert gas (TIG), metal inert gas (MIG), laser beam welding (LBW), friction stir, spot welding, spot welding also even in hybrid welding. The micro structural changes, physical property grain development and Heat Affecting Zone (HAZ) during the welding are reviewed and compared.

Magnesium alloy matrix composite reinforced with constant weight fraction of 5% Cu and various weight fractions of (0%, 5%, 10%, 15%) titanium diboride (TiB2) fabricated by Powder Metallurgy route. In this work, the mechanical properties like hardness, impact strength, compression strength, and wear rate of the Mg-Cu alloy and fabricated composites were investigated. The results showed that the addition of weight percentage of 15% TiB2 increased the hardness value about 58.56 HV, due to better bonding between the Mg-Cu and TiB2. Further, impact and compressive strengths improved, as the weight percentage of TiB2 increased. Uniform distribution of reinforced particles enhanced the impact strength and the work hardening effect improved the compression strength. Moreover, the wear rate decreased about 0.0112 mg by the addition of weight percentage of 15% TiB2. X-ray diffraction (XRD) analysis was carried out for each composition. Optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) tests were conducted to study the characterization of the base alloy and the prepared new composite.

Availability of clean water is diminishing in a frightening rate due to rapid depletion and contamination of potable water assets by human being. Hence solar desalination using SS can be the economical and best efficient method to purify the saline water as compared to other conventional desalination approaches. But this approach is not practiced extensively because of its low output and performance. Numerous researchers have done various tests and worked frequently to raise the output of SS. This current survey is done to review various influences such as solar intensity, water depth, glass roof angle, temperature difference and modifications such as insulation, external condenser, nanofluids, collectors, reflectors and PCM that can promote the output of SS. This survey is helpful to elevate the knowledge level in this field and also assist various researchers in choosing the proper methods and modifications that raise the output of SS.

In spite of the summer monsoon’s importance in determining the life and economy of an agriculture-dependent country like India, committed efforts toward improving its prediction and simulation have been limited. Hence, a focused mission mode program Monsoon Mission (MM) was founded in 2012 to spur progress in this direction. This article explains the efforts made by the Earth System Science Organization (ESSO), Ministry of Earth Sciences (MoES), Government of India, in implementing MM to develop a dynamical prediction framework to improve monsoon prediction. Climate Forecast System, version 2 (CFSv2), and the Met Office Unified Model (UM) were chosen as the base models. The efforts in this program have resulted in 1) unparalleled skill of 0.63 for seasonal prediction of the Indian monsoon (for the period 1981–2010) in a high-resolution (∼38 km) seasonal prediction system, relative to present-generation seasonal prediction models; 2) extended-range predictions by a CFS-based grand multimodel ensemble (MME) prediction system; and 3) a gain of 2-day lead time from very high-resolution (12.5 km) Global Forecast System (GFS)-based short-range predictions up to 10 days. These prediction skills are on par with other global leading weather and climate centers, and are better in some areas. Several developmental activities like coupled data assimilation, changes in convective parameterization, cloud microphysics schemes, and parameterization of land surface processes (including snow and sea ice) led to the improvements such as reducing the strong model biases in the Indian summer monsoon simulation and elsewhere in the tropics.

This study shows the active role of subsurface ocean temperature in the evolution of coupled intra-seasonal oscillation (ISO) in the Bay of Bengal (BoB) using multi-satellite observations and ocean analysis product. Satellite-derived humidity profiles obtained from the atmospheric infrared sounder (AIRS) show that intense rains over the BoB are associated with the moistening (drying) in the lower and mid-troposphere during the active (break) phase of summer intraseasonal oscillation (ISO). Anomalous moistening in the mid-troposphere up to 500 hPa ahead of the maximum precipitation band over north BoB gives a precursor signal for the northward movement of the rain band. During the active (break) phase, the upper-tropospheric positive (negative) temperature anomaly ahead of the maximum rain band also sets a precondition by heating the mid- to upper troposphere. Daily subsurface temperature from Global Ocean Data Assimilation System (GODAS) analysis show that during the active phase, tropospheric moistening (drying) coincides with the subsurface warm (cold) temperature up to 200-m depth. The upper ocean warms uniformly by ~ 1 °C during the active phase as compared to the break phase in the entire BoB. The presence of a thin warm layer below the maximum rain band creates an environment conducive to sustaining the active phase on the ISO time scale. A positive sea surface temperature (SST) anomaly along with upper ocean warming ahead of a rain band in the north BoB in association with lower and mid-tropospheric moistening sets a precondition for the northward movement of the rain band. The anomalous warming (cooling) in the thermocline is associated with deeper (shallower) thermocline depth [23° isotherms (D23)] and coincides with the mixed-layer warming.