Manoj Kumar Rangaswamy

The present study deals with the fabrication of polyvinyl alcohol composites reinforced with 10, 20, 30, 40, 50, 60, 70 wt% of date palm leaf fibers. Among these 60 wt% is providing good sound absorption because of the increase of porosity. Next to acoustic behaviour of composites analysed by varying thickness from 20-40mm by keeping density constant (60 wt %). An impedance tube setup is used for the measurement of the sound absorption coefficient. The sound absorption properties of composite samples increased significantly by increasing the thickness of materials with a constant density. Initially, sound absorption was measured without an air gap behind the samples and it was observed that date palm leaf fibers composite behaves like a good sound energy absorber in the frequency range of 1500-6300 Hz. Another experiment performed by introducing the air gap behind the samples varies from (10-30mm). This configuration dissipating more energy of sound waves as compared to without air gap because air is also absorbing some amount of energy. Air gap with this sample can be used as a new method for the fabrication of natural fiber-reinforced composites.

Making a decision is one of the crucial tasks for choosing the best optimal solution for various problems related to the decision making. Decision can be made easily for the problems with one or two input criteria and many choices/alternatives as solution. Whereas, it’s very difficult to take the decision for the problems with more than two input criteria and many choices/alternative as solution. This type of problems can be solved with Multi-Criteria Decision-Making (MCDM) approaches. There are many MCDM approaches in the field of decision making research. This study considers two efficient MCDM approaches namely Simple Additive Weighting (SAW) method and Weighted Product Method (WPM) to solve the multi criteria decision making problems. These two MCDM approaches are implemented for underground mining method selection problem for the Indian metal mine X as a case study. For the specified mine SAW and WPM provides the Room and Pillar as a suitable mining method for extraction of the minerals.

Power electronics has the ability to control electric power in the most effective and economical way and it plays a leading role in the transmission, distribution and application of electrical power, However, the non-linear properties of power electronic devices add harmonics which greatly reduces the power efficiency and hence the Power quality has become the severe issue for both customers and utility. Many devices are designed to increase the efficiency of electricity at the customer end. Now a days, UPQC has proven to be an effective device used to alleviate power quality issues in the distribution network. It has the ability to eliminate both voltage and current based problems simultaneously. This paper presents, 3-phase 3-wires UPQC system and 3-phase 4-wires UPQC system modelled using MATLAB which is used to eliminate the power quality issues. The shunt APF of UPQC uses PQ-theory based control technique and nonlinear adaptive filter is used in the series APF of UPQC. The THD analysis is used to determine the efficiency of UPQC. On comparing the results, it can be seen that the THD value with UPQC is less, suggesting an increase in power efficiency.

Environmental impact assessment is essential to meet the objectives of sustainable product design. The environmental impact should be measured at the initial stages of product design to minimize the impact. In this paper, we demonstrate the application of a computer-aided design (CAD) tool to measure the environmental impact during the design stage. SolidWorks software uses the Life Cycle Assessment (LCA) model to measure the environmental impact such as energy consumption, carbon footprint, and air-water pollution. The spur gear model is used to demonstrate the process of assessing environmental impact using the CAD tool. The input parameters such as material, manufacturing process, region, transportation method, and product usage play an essential role in the environmental impact. The results indicate that the environmental impact can be reduced by optimizing the parameters by selecting alternatives using the CAD tool at the initial design stage.