Among all machining processes in the industry, surface grinding is one of the most extensively used procedures for smooth finishing of the end products. The major operating input parameters that influence product's surface quality is the coolant concentration which controls the Metal Removal Rate (MRR), surface roughness, surface damage, tool wear, etc. Low alloy steel possesses properties such as precise chemical composition and exhibits better mechanical properties such as high yield strength, ability to withstand high temperatures and low ductility, etc. In the second paper, "Optimization of Grinding Environment for Surface Grinding of Low Alloy Steel Using Analytic Hierarchy Process and Artificial Neural Network", the authors, Pritam Chakraborty, Kingshuk Kundu and Sirsendu Mahata, have taken up the surface grinding of low alloy steel at different coolant concentrations, besides dry environment. The experimental results are optimized using Analytic Hierarchy Process (AHP), and later in Artificial Neural Network (ANN) environment to predict the optimum solution. The AHP results indicated 1:20 concentration to be the best grinding environment (experimental) among the four alternatives, whereas the ANN (MATLAB) output at 1:30 is the optimum coolant concentration among the 11 alternatives.

In air-conditioning, the bypass factor can be considered to represent the fraction of the total air which does not come into contact with coil surface. This is attributed to coil inefficiency and some amount of air just bypassing the coil without getting affected by it. The passage of air through the gaps comes in contact directly with the coil, and cooling or heating of the air takes place through direct heat transfer. A lower bypass factor indicates efficient cooling. There are different operating variables, including coil geometry, in order to design an efficient cooling system without compromising the energy losses. In the third paper, "Quantifying Bypass Factor Variability of a Cooling Coil in an Air-Conditioning System", the authors, Swastika Talukder, Spandan Samanta, Manaswita Karmakar, Priyanshu Roy and Sanchayan Mukherjee, have experimentally studied the variation of bypass factor corresponding to different inlet areas and weather conditions-by changing the airflow rate, cross-sectional area and the inlet temperature. They have noted that the bypass factor rises sharply as the inlet air velocity increases. The authors have further analyzed the ascending trend of bypass factor-with a gradual rise in the air temperature-at different inlet openings.

The use of traditional method of food drying, in broad sunlight and open air, i.e., sun drying, finds application all over the world, with the increasing need for food quantity all over world. However, due to the possibility of food contamination, the development of more sophisticated methods of solar drying-wherein indirect solar radiation is used to collect the solar energy by heating up the air volume in collectors and then transferring the hot air to an enclosure, where the products are laid out for drying-finds an important application. It is an established fact that pebbles-a low-cost material-possess superior thermophysical property than sand. Hence, in the fourth paper, "Design and Development of a Cost-Effective Mixed Mode Solar Crop Dryer with Black-Coated Pebbles", the authors, Prem Kumar S, Krishnappa G B and D Madhu, have selected black-coated pebbles as heat storage material to develop a mixed-mode solar crop dryer. They have noticed that the black-coated pebbles-which enhance energy absorption-help to reduce the sudden fall of the dryer cabin temperature during late drying hours and increase the operating time, thereby decreasing the relative air humidity and increasing the water absorption capacity of air. Thin films find various applications due to their advantages over other bulk materials, and find application in micro- and nano-electronics. High quality thin films exhibit a variety of optical, magnetic and electrical properties, and are generally used to improve surface properties such as transmission, hardness, abrasion resistance, absorption, etc. of the material surfaces. The use of thin films to enhance the physical and chemical properties of materials is omnipresent in today's world. In the last paper, "Simulation of Particle Growth in Thin Films", the author, Rahul Basu, has applied simulation using WOLFRAM, and equations of heat and mass transfer are used to obtain a quasi-steady state solution result, where the growth is stabilized until the desired size and distribution is arrived at. The results reveal that the spherical melting model-with a typical pitch of 150 U-is much more stable and travels faster than cylindrical model.