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Frictional sliding contact problems between laterally graded orthotropic half-planes and a flat rigid stamp are investigated. The presented study aims at guiding engineering applications in the prediction of the contact response of orthotropic laterally graded members.

The solution procedure is based on a finite element (FE) approach which is conducted with an efficient FE analysis software ANSYS. The spatial gradations of the orthotropic stiffness constants through the horizontal axis are enabled utilizing the homogeneous FE approach. The Augmented Lagrangian contact algorithm is used as an iterative non-linear solution method in the contact analysis.

The accuracy of the proposed FE solution method is approved by using the comparisons of the results with those computed using an analytical technique. The prominent results indicate that the surface contact stresses can be mitigated upon increasing the degree of orthotropy and positive lateral gradations.

One can infer from the literature survey that, the contact mechanics analysis of orthotropic laterally graded materials has not been investigated so far. In this study, an FE method-based computational solution procedure for the aforementioned problem is addressed. The presented study aims at guiding engineering applications in the prediction of the contact response of orthotropic laterally graded members. Additionally, this study provides some useful points related to computational contact mechanics analysis of orthotropic structures.

The purpose of this study is to evaluate the perception and knowledge of standard food/meal portion size and related factors in young adults.

The present study was conducted on 1,000 volunteer young adults, consisting of 504 men and 496 women (18 and 28 years). The portion size of food/meal, amount of food measuring utensils and also nutritional knowledge were evaluated via a questionnaire and some visual materials.

Knowledge of portion sizes, amount of food each utensil holds and nutrition was evaluated via a questionnaire and some visual materials. Knowledge of portion size with respect to food groups (p = 0.015), meals (p < 0.001) and food measuring utensils (p = 0.002) and nutritional knowledge scores (p = 0.011) differed based on body mass indexes (BMI). Women had on mean a higher nutritional knowledge score than men (2.0 ± 1.3, 1.9 ± 1.1 points, respectively). The probability of having knowledge about food measuring utensils was 1.4-fold greater for individuals who had been previously educated about nutrition (p = 0.034). Individuals of the faculty of health sciences had higher mean scores for all portion scores (p < 0.05).

The study findings highlighted that portion knowledge and perception of young adults were affected by gender, BMI, enrolled faculty and nutritional knowledge status. This is the first study, through which the portion knowledge and perception subcomponents (food, meal and measuring utensils) are evaluated, indicating each subcomponent to be affected by distinct factors.

The heat transfer within a heat exchanger is highly influenced by geometry of the components especially those with hollow structures like tubes. This paper aims to intend toward the study of efficient and optimized heat transfer in the bends of superheater tubes, with different curvature ratio at constant Reynolds Number.

The effect of changing curvature ratio on enthalpy of the fluid passing through the superheater tubes for multi-pass system has been studied with the aid of computational fluid dynamics (CFD) using ANSYS 14.0. Initially a superheater tube with two pass system has been examined with different curvature ratios of 1.425, 1.56, 1.71, 1.85 and 1.99. An industry specified curvature ratio of 1.71 with two pass is investigated, and a comparative assessment has been carried out. This is intended toward obtaining an optimized radius of curvature of the bend for enhancement of heat transfer.

The results obtained from software simulation revealed that the curvature ratio of 1.85 provides maximum heat transfer to the fluid flowing through the tube with two pass. This result has been found to be consistent with higher number of passes as well. The effect of secondary flow in bends of curvature has also been illustrated in the present work.

The study of heat transfer in thermodynamic systems is a never-ending process and has to be continued for the upliftment of power plant performances. This study has been conducted on steady flow behavior of the fluid which may be upgraded by carrying out the same in transient mode. The impact of different curvature ratios on some important parameters such as heat transfer coefficients will certainly upgrade the value of research.

This computational study provided comprehensive information on fluid flow behavior and its effect on heat transfer in bends of curvature of superheater tubes inside the boiler. It also provides information on optimized bend of curvature for efficient heat transfer process.

This study aims to discover whether COVID-19 phobia has a positive and significant effect on the stress, depression and anxiety levels of industrial consumers in addition to reveal whether environmental awareness plays a mediating role between COVID-19 phobia and stress, depression and anxiety.

In this study, a quantitative method was used to reveal the role of anxiety, depression and stress (psychological effects) and environmental awareness caused by covid-19 phobia on industrial consumers. The universe of the study is small and medium-sized enterprises operating in the province of Sanliurfa, which is located in the southeast region of Turkey and the second largest city in the region, and are industrial customers. Questionnaire method was used in the study. In addition, data were collected from 406 people who agreed to participate in the study. In the study, in which intermediary and regulatory analyzes were made, the process macro program was used.

The results show that there is a medium relationship between COVID-19 phobia and environmental awareness; and COVID-19 phobia and stress, depression and anxiety. No relationship was found between environmental awareness and stress, depression and anxiety. COVID-19 phobia was found to have a positive and significant effect on environmental awareness and stress, depression and anxiety, while environmental awareness was found to have no effect on stress, depression and anxiety. Finally, environmental awareness was found to play a mediating role between COVID-19 phobia and stress, depression and anxiety.

In this study, four hypotheses were developed. Of these hypotheses, three are for the simple effect and one for the mediation effect. Out of four hypotheses, three were supported. The most important inference obtained from the study was finding the mediation effect of environmental awareness between COVID-19 phobia and anxiety, depression and stress.

To the best of the authors’ knowledge, no studies in the literature were made on the relationship among COVID-19 phobia, environmental awareness, stress, depression and anxiety. This study also examines the mediating effect of environmental awareness in the relationship between COVID-19 phobia and stress, depression and anxiety. The fact that the study is on the negative effects of the pandemic on one of the most affected occupational group also increases its original value.