OPTIMIZATION OF MIG WELDING PARAMETERS FOR IMPROVING STRENGTH OF WELDED JOINTS

The problem that has faced the manufacturer is the control of the process input parameters to obtain a good welded joint with the required weld quality. Traditionally, it has been necessary to study the weld input parameters for welded product to obtain a welded joint with the required quality. To do so, requires a time-consuming trial and error development method. Then welds are examined whether they meet the requirement or not. Finally, the weld parameters can be chosen to produce a welded joint that closely meets the joint qualities. Also, what is not achieved or often considered is an optimized welding parameters combination, since welds can often be formed with very different parameters. In other words, there is often a more ideal welding input parameters combination, which can be used. In this thesis, the influence of welding parameters like welding current, welding voltage, welding speed on ultimate tensile strength (UTS) of AISI 1050 mild steel material during welding. A plan of experiments based on Taguchi technique has been used. An Orthogonal array, signal to noise (S/N) ratio and analysis of variance (ANOVA) are employed to study the welding characteristics of material & optimize the welding parameters. The result computed is in form of contribution from each parameter, through which optimal parameters are identified for maximum tensile strength. From this study, it is observed that welding current and welding speed are major parameters which influence on the tensile strength of welded joint

New record of the flasher scorpionfish, Scorpaenopsis macrochir Ogilby, 1910 (Scorpaeniformes, Scorpaenidae) from Indian waters

Based on two specimens of the flasher scorpionfish, species of Scorpaenopsis macrochir Ogilby, 1910 (85-96 mm, TL) collected from the Visakhapatnam coastal waters, India, we described S. macrochir as the new record from Indian waters. This species is characterized by having 12 dorsal spines, medial surface of pectoral fins with a black subterminal band along entire margin of fin; supraorbital spine ending in a single spinous point and unserrated ocular spines. Nasal spines usually divided into two to six small points. The present study describes full description of the species with illustrations

A qualitative analysis of perspectives of district level frontline managers in Karnataka during first wave of COVID 19

With the emergence of pandemic, health sector has been facing innumerable challenges right from prevention to management of COVID-19. This study attempts to understand these factors from a local perspective that will help in better planning and management of situation for the future. Karnataka was one of the 8 states selected as part of a multisectoral qualitative study. Perspectives of frontline managers regarding the management of COVID 19 pandemic situation were taken by in depth interviews. Deductive thematic analysis from the audio recordings and transcripts showed public apprehensions, gaps in decentralized approach and specific guidelines, monitoring difficulties and workforce related issues as factors of concern

Filter Bank Multicarrier Modulation for Spectrally Agile Waveform Design

In recent years the demand for spectrum has been steadily growing. With the limited amount of spectrum available, Spectrum Pooling has gained immense popularity. As a result of various studies, it has been established that most of the licensed spectrum remains underutilized. Spectrum Pooling or spectrum sharing concentrates on making the most of these whitespaces in the licensed spectrum. These unused parts of the spectrum are usually available in chunks. A secondary user looking to utilize these chunks needs a device capable of transmitting over distributed frequencies, while not interfering with the primary user. Such a process is known as Dynamic Spectrum Access (DSA) and a device capable of it is known as Cognitive Radio. In such a scenario, multicarrier communication that transmits data across the channel in several frequency subcarriers at a lower data rate has gained prominence. Its appeal lies in the fact that it combats frequency selective fading. Two methods for implementing multicarrier modulation are non-contiguous orthogonal frequency division multiplexing (NCOFDM)and filter bank multicarrier modulation (FBMC). This thesis aims to implement a novel FBMC transmitter using software defined radio (SDR) with modulated filters based on a lowpass prototype. FBMCs employ two sets of bandpass filters called analysis and synthesis filters, one at the transmitter and the other at the receiver, in order to filter the collection of subcarriers being transmitted simultaneously in parallel frequencies. The novel aspect of this research is that a wireless transmitter based on non-contiguous FBMC is being used to design spectrally agile waveforms for dynamic spectrum access as opposed to the more popular NC-OFDM. Better spectral containment and bandwidth efficiency, combined with lack of cyclic prefix processing, makes it a viable alternative for NC-OFDM. The main aim of this thesis is to prove that FBMC can be practically implemented for wireless communications. The practicality of the method is tested by transmitting the FBMC signals real time by using the Simulink environment and USRP2 hardware modules

SFMToolbox: an ArcGIS Python Toolbox for Automatic Production of Maps of Soil Fertility

SFMToolbox is an ArcGIS Python toolbox developed in ArcGIS Desktop (ArcMap) to perform preprocessing tasks for the automatic creation of maps of soil fertility parameters. Through SFMToolbox, users can automatically produce 12 soil fertility parameter maps as a batch at one time. It is easy to use, where users can only provide input; the output files are automatically created from the name of the sample point and saved in the defined workspace. During the execution of the tools, various processes, such as Inverse Distance Weighted (IDW) – a technique of interpolation, reclassification, adding color, merging, projection, area calculation, and legend are done automatically for all 12 parameters at the same time. The SFMToolbox was validated as part of the following case study: village – Kashipur, tehsil – Balrampur, district – Balrampur, state – Uttar Pradesh, Country – India. The results show that the user can quickly generate maps and save time, improve accuracy, and reduce human intervention and ensure uniformity among maps. This toolbox also applied to Cycle II data from the Government of India’s Soil Health Card (SHC) scheme and timely produced 12-parameters soil nutrient maps for 630 districts in a uniform format. The toolbox may be used by public and private organizations to make timely decisions on agricultural and environmental issues

The Ichthyofaunal diversity in the freshwater tidal stretch along the Kalingapatnam estuary, Srikakulam, Andhra Pradesh, India : Ichthyofaunal diversity at Kalingapatnam estuary

The present study elucidates the ichthyofaunal diversity of Kalingapatnam estuary in the North- east coast of Andhra Pradesh, India. A detailed analysis of piscine diversity revealed a total of 97 species of fresh water, estuary and marine fish belonging to 26 orders, 53 families, and 85 genera, collected three landing locations for the first time. In the present investigation, recorded genera out of 85, the homogeneous percentage was observed of Perciformes and Siluriformes had the highest with 11.76%, followed by Acanthuriformes, Cypriniformes 9.41%, Clupeiformes 8.23%, Carangiformes 4.70%, Beloniformes, Canthuriformes, Cichliformes, Spariformes, Tetraodontiformes 3.52%, Carcharhiniformes, Anabantiformes, Centrarchiformes, Gobiiformes, Mugiliformes, Mulliformes, Scombriformes, Synbranchiformes each with 2.35%. Anguilliformes, Cyprinodontiformes, Elopiformes, Gonorynchiformes, Istiophoriformes, Kurtiformes and Osteoglossiformes each with 1.17%. The habitation of fishes were primarily benthic/ demersal, with  contributing to 40.20%, followed by benthopelagic 28.86%, pelagic and reef-associated fish 15.46% in this estuary. The omnivores have a highest percentage of 50.98%, followed by the carnivorous 25.49%, and the herbivorous18.36%. According to IUCN (2023) status the ichthyofaunal diversity were recorded in the current investigation

New record of the flasher scorpionfish, Scorpaenopsis macrochir Ogilby, 1910 (Scorpaeniformes, Scorpaenidae) from Indian waters

Based on two specimens of the flasher scorpionfish, species of Scorpaenopsis macrochir Ogilby, 1910 (85-96 mm, TL) collected from the Visakhapatnam coastal waters, India, we described S. macrochir as the new record from Indian waters. This species is characterized by having 12 dorsal spines, medial surface of pectoral fins with a black subterminal band along entire margin of fin; supraorbital spine ending in a single spinous point and unserrated ocular spines. Nasal spines usually divided into two to six small points. The present study describes full description of the species with illustrations

An occurrence of the rare Sharptail Mola Masturus lanceolatus (Lienard, 1840) (Tetraodontiformes: Molidae), in the coastal waters of Visakhapatnam, India

A single specimen of the Sharptail Mola Masturus lanceolatus (Lienard, 1840) (total length 1.39m) was collected from a commercial trawler operated from Visakhapatnam at a depth range of 150–300 m, east coast of India on 12 April 2016.  It was recorded for the first time in Visakhapatnam.  A detailed description, morphometric and meristic characters of the species are provided in this paper </div

New Record of Mozambique Scorpionfish, Parascorpaena mossambica (Peters, 1855), (Actinopterygii: Order, Scorpaeniformes; Family: Scorpaendiae) From Indian Waters

Parascorpaena mossambica is one of the rare species of Scorpaenidae in the Visakhapatnam coastal waters, India. Ten specimens are characterized by Dorsal fin IX 9; Anal fin III 5-6; Pectoral fin rays 15; Lateral line scales 43-44; Lateral line Pored scales 23-24; Lateral transverse scale scales 6-7/1/12-14; lachrymal bone with two lower strong antrose spines, anterior pointed and directed forward, tip reaching dorsal margin of upper lip, covered with skin; posterior one directed forward and slightly downward; suborbital with three spines. Only few records have been made in the whole Indian waters. Due to its rarity, P. mossambica is poorly studied and little known about their biology, ecology and distribution. In the present study provides additional data on this rare species. In particular, we describe its habitat, ecology, presence and distribution with several new records in Indian waters.   Keywords: Scorpaenidae, fish, Parascorpaena mossambica, Visakhapatna