Tactile Roughness Perception of Virtual Gratings by Electrovibration

Realistic display of tactile textures on touch screens is a big step forward for haptic technology to reach a wide range of consumers utilizing electronic devices on a daily basis. Since the texture topography cannot be rendered explicitly by electrovibration on touch screens, it is important to understand how we perceive the virtual textures displayed by friction modulation via electrovibration. We investigated the roughness perception of real gratings made of plexiglass and virtual gratings displayed by electrovibration through a touch screen for comparison. In particular, we conducted two psychophysical experiments with 10 participants to investigate the effect of spatial period and the normal force applied by finger on roughness perception of real and virtual gratings in macro size. We also recorded the contact forces acting on the participants' finger during the experiments. The results showed that the roughness perception of real and virtual gratings are different. We argue that this difference can be explained by the amount of fingerpad penetration into the gratings. For real gratings, penetration increased tangential forces acting on the finger, whereas for virtual ones where skin penetration is absent, tangential forces decreased with spatial period. Supporting our claim, we also found that increasing normal force increases the perceived roughness of real gratings while it causes an opposite effect for the virtual gratings. These results are consistent with the tangential force profiles recorded for both real and virtual gratings. In particular, the rate of change in tangential force ($dF_t/dt$) as a function of spatial period and normal force followed trends similar to those obtained for the roughness estimates of real and virtual gratings, suggesting that it is a better indicator of the perceived roughness than the tangential force magnitude.Comment: Manuscript received June 25, 2019; revised November 15, 2019; accepted December 11, 201

DETERMINATION of FINANCIAL LITERACY LEVEL: A STUDY on HITIT UNIVERSITY FACULTY of ECONOMICS and ADMINISTRATIVE SCIENCES STUDENTS

Financial literacy is the level of financial knowledge, attitude and behavior that enables individuals to manage their income, expenses and assets in a way that does not cause financial problems both today and in the future. As individuals' financial literacy levels increase, unnecessary consumption and waste of resources will decrease and the efficiency of investments will increase. Increasing the level of financial literacy will ensure a more balanced formation of asset prices in financial markets and prevent the formation of price bubbles in the markets. Today, financial markets around the world are almost integrated, financial transactions have become possible quickly through portable electronic devices. In this environment, the difference in welfare between individuals and societies with financial literacy and individuals and societies without financial literacy has increased more than in any other period in history. In this study, it is aimed to measure the financial literacy level of the students of Hitit University Faculty of Economics and Administrative Sciences located in the province of Çorum. The data of the study were obtained from a questionnaire with the participation of 400 students studying in 5 different departments. By using the percentages of the correct answers given to the questions, success scores were created on the basis of departments. With the help of the T-test and ANOVA tests, the relationship between students' financial literacy and whether they use department, gender, class and credit card was determined. As a result of the study, it was determined that there are significant relationships between the departments and classes in which students study and their financial literacy, and no significant relationships were found between their credit card and internet banking usage and gender and financial literacy