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At present, composites are being utilized on account of simplicity in manufacturing and their characteristics are low weight, non-abrasive, non-flammable and non-harmful. This article attempts to achieve good mechanical properties of the wood and woven jute based natural fiber-reinforced plastics. The required composite materials were fabricated by using a hand layup method. The fabricated laminates were immersed in liquid nitrogen at 77 K for cryogenic treatments. The following parameters are (i) wood density, (ii) wood weight ratio, (iii) woven jute type, (iv) number of jute layers, (v) cryogenic treatment durations and (vi) alkaline treatment durations, each at three different levels were picked for composite development by utilizing the Gray-Taguchi method. Mechanical testing of fabricated laminates was done as per ASTM standards to estimate compressive, double shear and hardness properties. Based on the L27 (36) orthogonal array of the Grey Taguchi technique, 27 investigational trials were conducted. According to the Gray relation analysis, 300 kg m−3 of wood density with a weight ratio of 12%, three layers of 350 gsm woven jute, 60 min of cryogenic treatment and 4 h of alkaline treatments resulted in good mechanical strength of the composites. Based on the Analysis of Variance, wood density was identified as the most influencing parameter that contribute up to 35.65% to the improvement of the mechanical strength of hybrid composites. The morphological expositions of NaOH treated hybrid composites and degree of fibers’ dispersion into the matrix were discussed based on Optical and SEM images.

Natural fibre-based composites are replacing traditional materials in a wide range of structural applications that are used in different environments. Natural fibres suffer from thermal shocks, which affects the use of these composites in cold environment. Considering these, a goal was set in the present research to investigate the impact of cryogenic conditions on natural fibre composites. Composites were developed using polyester as matrix and jute-fibre and waste Teak saw-dust as reinforcement and filler, respectively. The effects of six parameters, viz., density of saw-dust, weight ratio of saw-dust, grade of woven-jute, number of jute layers, duration of cryogenic treatment of composite and duration of alkaline treatment of fibres on the mechanical properties of the composite was evaluated with an objective to maximise hardness, tensile, impact and flexural strengths. Taguchi method was used to design the experiments and response-surface methodology was used to model, predict and plot interactive surface plots. Results indicated that the duration of cryogenic treatment had a significant effect on mechanical properties, which was better only up to 60 min. The models were found to be statistically significant. The study concluded that saw-dust of density 300 kg/m3 used as a filler with a weight ratio of 13 wt.% and a reinforcement of a single layer of woven-jute-fibre mat of grade 250 gsm subjected to alkaline treatment for 4 h in a composite that has undergone 45 min of cryogenic treatment presented an improvement of 64% in impact strength, ca. 21% in flexural strength, ca. 158% in tensile strength and ca. 28% in hardness.

Through this work an attempt was made to improve the mechanical properties of composite materials by using a process called Gray-Taguchi. Hand lay-up approach has been adopted for manufacturing. Here, Woven Hemp fiber diameter, Number of hemp layer, coconut shell powder content and cryogenic temperature ranges at different levels were incorporated as result parameter. ASTM specifications were set for the manufactured laminates to perform the mechanical tests. Hemp and coconut shell powder material are exposed to 5 percent NaOH treatment to create the matrix-fiber interface exchange. To optimize composite, the Taguchi method is combined with the Gray relational analysis. The quality targets are set for mechanical properties that include compressive strength, tensile strength, impact strength and flexural strength. This study involved nine experiments on the orthogonal array of the L9 (34) Taguchi method. A combination of the composite, Gray relational analysis was applied to obtain the optimal parameter. The results of optimum parameters were verified using Conformation test. The maximum prescribed parameters are 0.7 mm woven hemp diameter, two hemp layers, 10 percent CSP content weight, and -130°C cryogenic temperature range provides the maximum energy of impact, tensile strength and flexural strength.

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The rapid development of data transfer through internet made easier to send the data accurate and faster to the destination. Besides this, anyone can modify and misuse the valuable information through hacking. Steganography attempts to hide the secret information and make communication undetectable. Steganography is used to conceal the secret information so that no one can sense the information. Steganographic method has many challenges such as high hiding capacity and imperceptibility.This paper presents Video Steganography with digital watermarking techniques as an efficient and robust tool for protection.