National Institute of Technology, Meghalaya

About: National Institute of Technology, Meghalaya is a education organization based out in Shillong, India. It is known for research contribution in the topics: Control theory & Computer science. The organization has 503 authors who have published 1062 publications receiving 6818 citations. The organization is also known as: NIT Meghalaya & NITM.

Effect of Powder Particle Concentration and Tool Electrode Material amid Zinc Powder-Mixed µEDM of Biocompatible Mg Alloy AZ91D

Abstract: Magnesium (Mg) alloys exhibit high strength and biocompatibility, coupled with a unique characteristic that is the ability to degrade over time. These characteristics of Mg alloys led to the development of several biodegradable medical implants such as screw, pin, and plate. Powder-mixed micro-electric discharge machining (PM-μEDM) was found to substantially improve the surface and metallurgical properties of biodegradable alloys and therefore, it was used in this study to investigate the machinability of Mg alloy AZ91D. PM-μEDM was performed at varying zinc (Zn) powder particle concentrations (0 to 8 g/l) using copper and brass tool electrodes. The effect of these input control variables on the machining time, dimensional deviation, and characteristics of the machined surface was experimentally examined. The machined surfaces were primarily analyzed by field-emission scanning electron microscope, energy-dispersive spectrometry, and x-ray diffraction (XRD). The findings showed a significant reduction in the machining time and dimensional deviation during PM-μEDM at 4 g/l powder particle concentration using the copper tool electrode. Moreover, the presence of resolidified debris, powder particles, and formed metal oxides and carbides in the recast layer, produced with the aid of the copper tool electrode at 4 g/l powder particle concentration, exhibited a considerable surface modification.

A novel CMOS-MEMS integrated pressure sensing structure based on current mirror sensing technique

Abstract: Purpose – The present paper aims to propose a basic current mirror-sensing circuit as an alternative to the traditional Wheatstone bridge circuit for the design and development of high-sensitivity complementary metal oxide semiconductor (CMOS)–microelectromechanical systems (MEMS)-integrated pressure sensors. Design/methodology/approach – This paper investigates a novel current mirror-sensing-based CMOS–MEMS-integrated pressure-sensing structure based on the piezoresistive effect in metal oxide field effect transistor (MOSFET). A resistive loaded n-channel MOSFET-based current mirror pressure-sensing circuitry has been designed using 5-μm CMOS technology. The pressure-sensing structure consists of three identical 10-μm-long and 50-μm-wide n-channel MOSFETs connected in current mirror configuration, with its input transistor as a reference MOSFET and output transistors are the pressure-sensing MOSFETs embedded at the centre and near the fixed edge of a silicon diaphragm measuring 100 × 100 × 2.5 μm. This a...