International Journal of Neutrosophic Science IJNS 2690-6805 2692-6148 10.54216/IJNS https://www.americaspg.com/journals/show/302 2020 2020 Malang Institute of Agriculture - IPM, INDONESIA V. Christianto Dept. Math and Sciences, University of New Mexico, Gallup, NM, USA F. Smarandache Department of Statistics, Faculty of Science, King Abdulaziz University, Jeddah 21551, Saudi Arabia M. Aslam During scientific demonstrating of genuine specialized framework we can meet any sort and rate model vulnerability. Its reasons can be incognizance of modelers or information mistake. In this way, characterization of vulnerabilities, as for their sources, recognizes aleatory and epistemic ones. The aleatory vulnerability is an inalienable information variety related with the researched framework or its condition. Epistemic one is a vulnerability that is because of an absence of information on amounts or procedures of the framework or the earth [7]. Right now, we examine fourfold neutrosophic numbers and their potential application for practical displaying of physical frameworks, particularly in the unwavering quality evaluation of engineering structures. Contribution: we propose to extend the notion of standard deviation to by using symbolic quadruple operator. 2020 2020 72 76 10.54216/IJNS.020202 https://www.americaspg.com/articleinfo/21/show/302