Journal on Today's Ideas - Tomorrow's Technologies

Effect of Bacteria Inoculums on Compressive Strength

Sat, 03 Jul 2021 00:00:00 +0530

The use of bio-concrete is increasing in the present day context and researchers are working on strength and durability characteristics of concrete using bacteria species which have shown calcite precipitation. Three different species of bacteria namely P. Fluorescence, B. Pumilis and B. Subliis that have calcite precipitation properties have been investigated in this study. The investigations were carried first on cement mortar (CM) cubes using these three bacteria species suspension of 20%; 40% and 60% having colony forming units P. Fluorescence (10⁸ CFU/ml), B. Pumilis (10⁶ CFU/ml) and B. Subtilis (10⁸ CFU/ml) respectively. The 40% suspension in all the three cases has shown increased compressive strength as compared to 20% and 60%. The compressive strength measured showed increase (CS) of 18%; 12% for P. Fluorescence; B. Subtilis and decrease of 35% with B. Pumilis respectively. B. Subtilis with optimized 40% suspension having CFU 10x10⁸/ml showed 4.32% ; 5.56%; and 3.81% increase in CS of CC cubes with 3 days; 7 days and 28 days respectively and 5.92% overall increase in CS of CC cubes as compared to the 3 days CS of control cube.
ABBREVIATIONS
SDW: Sterile Distilled Water; SHC: Self-Healing Concrete; PCR: Polymerase Chain Reaction; BC: Bacterial Concrete; CP: Calcite precipitation; CS: Compressive Strength; CC: Cement Concrete; CM: Cement Mortar; MTCC: Microbial Type Culture Collection; CFU: Colony Forming Unit/ml

Antenna Design and Fabrication with Circular Microstrip Patch: A Review

M. S. Kasbe, T. H. Mujawar, B. Gabane, R.V. Shinde — Sat, 03 Jul 2021 00:00:00 +0530

The paper presents a review on antenna designing and fabrication techniques with Microstrip Patch (MSP) development. The requirements of MSP are remote controlling, mobile communication, space communication and all wireless communication areas. Aim of this development is to provide a new approach of the designing and simulation of circular
MSP for 5.8 GHz operating frequency. CST MICROWAVE STUDIO (MWS) facilitates the quick and accurate analysis of high frequency (HF) antennas which gives the responses and results before fabrication of actual patch with complete technology for 3D EM. FR-4 glass epoxy material board is used for fabrication which is admired and adaptable highpressure thermoset plastic laminate grade with superior strength to weight ratios. Circular MSP is easy to fabricate, portable, lightweight and low cost antenna. N9923A Field Fox RF VNA (Vector Network Analyser) were used for studying and testing all the parameters of fabricated MSP.

A Migration to Online Teaching-Learning in School Education during COVID-19

Malik Mubasher Hassan, Tabasum Mirza — Sat, 03 Jul 2021 00:00:00 +0530

Prolonged school closures due to COVID-19 pushed the education system at all levels of India to the limits where structural weaknesses and other loopholes can be clearly visible. The significant challenges like lack of ICT infrastructure and digital competence of teachers, played an important role in the acceptance of new modes of teaching. Creating and delivering the educational content by using digital tools still remains a daunting task for many teachers. At the same time parents are overwhelmed with the burden to teach children at home and help them with online learning and bearing extra expenses of digital devices and internet services. Students, on the other hand, are struggling continually to adapt to a new learning environment that offers some flexibility along with some challenges. This study aims to present the challenges faced in instant migration of offline to online mode of teaching-learning by the stakeholders.

An Investigation on the Influence of Modeling Approach and Load Pattern on Seismic Performance of RC Structures

C. M. Ravikumar, L. K. Ashwini, M. Keshavamurthy — Tue, 22 Jun 2021 00:00:00 +0530

Non-linear Static Analysis serves as a suitable measure to evaluate the performance of a structural system. The careful selection of modelling approach and the load pattern is critical to arrive at an adequate performance evaluation. The present study seeks to evaluate and compare the response of an existing eight story reinforced concrete structure, through the application of different modeling approaches and load patterns prescribed by FEMA 356. The results indicates that, with extreme clarity, that in all cases, the shape of the lateral load distribution is what the response of the buildings is finely accustomed to. This is especially true when different patterns of load are considered. It can also be observed that there is a very small difference between various load patterns.