Indian Institute of Technology Guwahati

About: Indian Institute of Technology Guwahati is a education organization based out in Guwahati, Assam, India. It is known for research contribution in the topics: Catalysis & Computer science. The organization has 6933 authors who have published 17102 publications receiving 257351 citations.

Coupled tuned mass dampers for control of coupled vibrations in asymmetric buildings

Abstract: An arrangement of tuned mass dampers, termed coupled tuned mass dampers (CTMDs) has been introduced, where a mass is connected by translational springs and viscous dampers in an eccentric manner. The CTMD has coupled modes of lateral and rotational vibration, which have been utilized to control coupled lateral and torsional vibrations of asymmetric buildings. An efficient control strategy has been presented in this context to control displacements as well as acceleration responses of asymmetric buildings having asymmetry in both plan and elevation. The building is idealized as a simplified three-dimensional model with two translational and a rotational degrees of freedom for each floor. The principles of rigid body transformation have been incorporated to account for eccentricity between center of mass and center of rigidity. A nondominated sorting genetic algorithm (GA) has been used for solving the multi-objective optimization problem. Tuning of optimum locations of TMDs and their parameters have been done from the multiple pareto-optimal solutions obtained simultaneously. Comparative studies of performance of CTMD with conventional TMDs and bi-directional TMDs have been presented. It has been observed that CTMDs are more effective and robust in controlling coupled lateral and torsional vibrations of asymmetric buildings. The optimal locations have been observed to be reasonably compact and practically implementable for CTMDs. Copyright © 2005 John Wiley & Sons, Ltd.

CD 59 Targeted Ultrasensitive Electrochemical Immunosensor for Fast and Noninvasive Diagnosis of Oral Cancer

Abstract: Oral cancer (OC) is one of the important cancer types in human being and its early and quick diagnosis will help clinicians to develop suitable therapeutic strategies to improve the prognosis of cancer patients. In this direction, we report a label free impedimetric immunosensor to diagnose OC by detecting CD 59, an early stage and important OC biomarker. The immunosensor probe is fabricated by immobilizing CD 59 antibodies (anti-CD 59) on a self-assembled molecular layer of L-cysteine (Cys) on a gold electrode. The fabrication of sensor probe is characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The experimental conditions were optimized in terms of antibody concentration, temperature, pH, and incubation time in order to obtain maximum sensitivity. The CD 59 is qualitatively detected using EIS which shows a wide dynamic range between 1 fg mL(-1) and 1000 fg mL(-1) with a detection limit of 0.38 (+/- 0.03) fg mL(-1). The developed immunosensor is successfully applied for direct detection of CD 59 in clinically relevant human saliva samples. Interferences due to non-target cancer antigens, stability, and regeneration of the developed immunosensor was performed.

Temperature-Insensitive Fiber Bragg Grating Based Tilt Sensor With Large Dynamic Range

Abstract: We present a novel and simple temperature-insensitive fiber Bragg grating (FBG) based smart tilt sensor. The sensor design is free from any inherent mechanical joints/frictions with a capability to measure magnitude as well as the direction of the inclination. The first design is with a sensitivity of 0.00282 nm/° in a very large dynamic range of ± 35°. The sensor response is optimized against design parameters and observed to be completely reversible. Since there is a strain discrepancy on individual FBGs of the first design, a modified design is then proposed for optimization. An excellent sensitivity of 0.0395 nm/° , resolution of 0.013° and accuracy of 0.051° have been achieved. These features along with the freedom to tune the dynamic range, accuracy of measurement and the sensitivity of the proposed sensor to a desired operation range make the proposed sensor of extreme importance for practical engineering applications.