P. A. Prasob ¹, M. Sasikumar ¹, P. Tamil Selvan ¹

Affiliations
1 School of Mechanical and Building Science (SMBS), VIT University, Chennai Campus, Tamil Nadu, IN

Abstract

Background/Objective: The objective of this review paper is to know and verify the mechanical properties especially impact behavior of PMC under subzero temperature. Methods/Statistical Analysis: The focus of this paper is on the use of liquid nitrogen as cryogenic liquid, subzero temperature conditions and the mechanical durability of PMC including tensile strength, compressive strength, shear strength, fatigue. The low velocity impact of PMC is reviewed under the Charpy impact and the Drop weight impact. Also the progressive failure and damage of PMC under impact is given due importance in this paper. Applications/Improvements: Hybridization of PMC with synthetic, natural fibers and micro fillers can enhance the mechanical properties of PMC at liquid nitrogen temperature. Findings: The tensile load response for a composite is very much dependent on the strength properties of the reinforcement fibers, since they are high compared to the resin system on its own. The compression testing of the composites is very challenging due to various reasons. The application of compressive load on the cross section is done in three ways: directly apply the compressive load on the ends of a specimen, loading the edges in shear and mixed shear and direct loading. The compression test results show that the mechanical properties at subzero temperature is comparatively better than properties of the PMC at room temperature. The impact testing of PMC in subzero temperature has better impact strength than PMC tested at room temperature. The reason being the brittleness of the matrix once exposed to liquid nitrogen the layers get contracted on cooling and load transfer does not take place as in the case of composite at room temperature resulting in failure.

Keywords

Cryogenics, Damage, Impact, Polymer Matrix Composite (PMC), Liquid Nitrogen, Subzero.

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P. Tamil Selvan ¹, S. Veni ¹

Affiliations
1 Department of Computer Science, Karpagam Academy of Higher Education, Coimbatore - 641021, Tamil Nadu, IN

Abstract

Background/Objectives: This paper proposes an Optimized Social Ant Based Sensitive Item Hiding (OSA-SIH) technique and expands the scope of quality privacy preservation for distributed data mining with optimal side effects on the original dataset. Methods/Statistical Analysis: in OSA-SIH technique, initially sensitive items for the given distributed dataset are evaluated using the social ant based relative item set distribution. Based on the evaluated dataset, optimal hiding of sensitive item is arrived with social ant based relative item set distribution even for larger item sets, ensuring time for optimal hiding. Next, sensitive item hiding is performed through multiplicative and transformational data perturbation. This data perturbation is based on socially cohesive relational rate between sensitive and non sensitive item sets, ensuring privacy preservation accuracy. The side effects on the modified dataset are checked for several users' requested item set distribution. Findings: The experimental results demonstrated that proposed technique out performed than the existing state of the art works in terms of privacy preservation accuracy, rate of side effects on the modified dataset, and time for optimal hiding. Improvement/Application: Experiments revealed that the proposed OSA-SIH technique

Keywords

Perturbation, Privacy Preserving Data Mining, Social Ant, Sensitive Item Hiding, Transformational Data Perturbation, Multiplicative Data Perturbation

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