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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.

Sudan’s challenges are deeply rooted in a complex web of societal, political, and health-related issues. The nation is currently experiencing a challenging period that is impacting various aspects of human life, including the healthcare system for the youth, who are significantly impacted by this crisis that has persisted for a decade. Sudan, located in northeastern Africa, is an Arab nation and a member of the Greater Horn of Africa, along with Ethiopia and South Sudan. Despite its strategic location near the Nile River – a hub for global oil trade and other merchandise – it does not possess any military equipment. Its history, unfortunately, is marked by prolonged social conflicts. These conflicts have significantly affected essential infrastructures, social services, and the overall well-being of the population. We examine the conflict through humanitarian and socio-economic factors affecting Sudan and its people. This chapter explores the role of global economic forces and international relations in Sudan’s ability to address these challenges. Secondly, we explore the social structures, power dynamics, and interdependencies, examining how institutions and societal functions hinder comprehensive issue resolution through structural functionalism. Lastly, we will analyze the legal recognition and protection as foundational elements for human rights and assess the acknowledgment of rights, its absence influences the endurance of multifaceted challenges like health care and educational system by the Right to have Rights.

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.

School principals should create a positive school climate through instructional leadership behaviors and support teacher autonomy to reach their ultimate goals. This study examines the relationship between the instructional leadership behaviors of school principals and teacher autonomy, testing the mediating role of school climate and the moderator role of teacher seniority.

This cross-sectional study tests the relationships between the variables with structural equation modeling. By stratified sampling method, research data from 739 teachers in six central districts of Ankara during the 2022–2023 academic year.

Results showed that school principals' instructional leadership behaviors, teacher autonomy, and perceptions of school climate were above average. The study also indicates that the instructional leadership behaviors of school principals are positive and significant predictors of teacher autonomy and school climate and that school climate is a positively significant predictor of teacher autonomy. Moreover, school climate partially mediates the relationship between instructional leadership and teacher autonomy, and teacher seniority has a moderator role.

This study is limited to the opinions of the teachers working in the official primary, secondary and general high schools in the districts of Ankara in the 2022–2023 academic year on the instructional leadership of the school principals, the teachers' perceptions of autonomy and the school climate. It has been observed that there is a relationship between the instructional leadership behaviors of school principals and teacher autonomy. It can be said that the instructional leadership behaviors of school principals support teachers to exhibit autonomous behaviors in instructional strategies and processes, curriculum, classroom management, professional development and communication.

It is seen that the instructional leadership behaviors of school principals affect teacher autonomy through school climate. It can be said that with the instructional leadership behaviors of school principals, the school climate is more democratic, success-oriented, sincere, supportive of teacher leadership and transforming conflicts into an opportunity for school development, thus affecting teachers' areas of autonomy. We can say that with the development of teachers' autonomy, more effective instructional strategies and instructional processes are developed, the curriculum is transferred with more permanent teaching techniques, professional communication is transformed into collective actions and more comprehensive studies are planned and implemented.

This study will extend the literature by revealing the complex link between instructional leadership, teacher autonomy, school climate and teacher seniority. Furthermore, this study estimates how these complex interactions emerge in non-western cultures with centralized educational structures.

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.