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Inner radius inspection is critical in the production of tubes, particularly those with small thicknesses, to ensure structural integrity and performance. Traditional ultrasonic methods often fall short in measuring thin-walled tubes, necessitating the use of eddy current method for its non-contact and highly sensitive capabilities. In this paper, we employ the finite element method (FEM) to calculate the output signal of a vertical surface probe in the vicinity of a finite conductive tube. We address the significant impact of edge effects, which can deteriorate the primary signal from material properties. The probe data are then used to determine the inner radius through a regression method, and an evaluation technique is proposed to inspect the ovality of the inner surface. Our results demonstrate the accuracy and efficiency of the FEM to predict coil impedance and regression methods to evaluate both the inner radius and the shape of the inner surface, even in the presence of noise. This research provides significant contributions to the field of tube inspection, particularly in industries where precision is paramount, such as oil and gas industries, automotive, and medical sectors.

Conductivity evaluation is crucial for monitoring the condition of metallic tubes during inspections and for assessing their service life. Eddy current testing (ECT) is a precise, non-contact method used for this purpose. Industries such as aerospace, power generation, and petrochemicals rely on precise condition monitoring, which requires a deep understanding of the relationship between conductivity variations and probe impedance of metallic tubes. However, experimental analysis of conductivity changes using coil impedance has limitations in terms of cost and complexity. Encircling coil methods provide overall information about the average conductivity of specimens but have limited ability to capture local variations such as hot spots. To address these issues, we propose using a finite element method (FEM) based approach to predict a ferrite core horizontal probe signal near non-ferromagnetic tubes. The probe data can be used to estimate conductivity through regression methods, and the impact of lift-off on ECT results is also investigated.

This paper presents a comprehensive investigation on the vibrations of reinforced concrete structure by graphene oxide powders (GOPs) using a polynomial displacement field and the Generalized Differential Quadrature Method (GDQM). The study focuses on analyzing the dynamic behavior of the structure and assessing the effects of three different distribution patterns of GOPs on its vibrations. To accurately model the deformation of the pressure vessel, a polynomial displacement field is employed, taking into account the complex geometrical and material properties of the structure. The results highlight the significant influence of the distribution pattern of GOPs on the natural frequencies of the spherical concrete pressure vessel. The analysis reveals that variations in the weight fraction and arrangement of GOPs have a direct impact on the stiffness and dynamic characteristics of the structure. Specifically, increasing the weight fraction of GOPs generally leads to higher natural frequencies, indicating enhanced structural rigidity. Moreover, the polynomial displacement field and GDQM demonstrate their effectiveness in accurately predicting the vibrations of the reinforced pressure vessel. The combination of these numerical techniques enables efficient and reliable analysis of the dynamic response, allowing for optimization of the design and performance of spherical concrete pressure vessels.

IL RUOLO DELL’INTELLIGENZA SOCIALE E DELLA RESILIENZA NELLO SPIEGARE LA TOLLERANZA AL DISAGIO DEGLI STUDENTI: UNO STUDIO DURANTE LA PANDEMIA DI COVID-19 Abstract Understanding the factors that influence or correlate with distress tolerance is very important. Therefore, the aim of this study was to investigate the role of social intelligence and resilience in explaining college students’ distress tolerance. A descriptive correlational study was carried out on 260 male college students of Farhangian University of Birjand, Iran in 2020/21. They completed Social Intelligence Scale, Resilience Scale, and Distress Tolerance Questionnaire. The results showed that there was a direct and significant relationship between social intelligence and distress tolerance (r = 0.473; p

Economical alumina precursors, derived from bauxite or nepheline ores, were calcined through a very short time process. Results showed that phases of the precursor are a key parameter on the flash calcination process. The number of structural water molecules is the dominant phenomenon. A porous and fine structure of activated alumina was developed as the hydroxyl groups are explosively driven off and establish a hydrothermal condition. The presence of gibbsite phase with larger particle size and most structural water molecules has better product properties in comparison of other alumina precursors phase with small particle size because water vapor pressure achieves a critical value for splitting particles and developing nucleation desirable phases. The changes rate of properties reaches to its maximum value for gibbsite phase at lower calcination temperature. FESEM images showed the precursor phase forms different morphologies of products like, nanodimensional, a coral-like co-continuous or loose particles surrounded with macropores. Resumen: Los precursores económicos de alúmina, derivados de minerales de bauxita o nefelina, se obtienen a través de un proceso de calcinación rápida. Los resultados mostraron que las fases del precursor son un parámetro clave en el proceso de calcinación rápida. El fenómeno dominante en este proceso es el número de moléculas estructurales que estén formando el agua. Cuando los grupos de hidroxilo se extraen de forma explosiva, elaboran un ambiente hidrotermal. El resultado genera alúmina activa con una estructura porosa y fina. A diferencia de otras etapas de los precursores de alúmina con el tamaño de partículas pequeñas, la gibbsite incluye el tamaño más grande de partículas con el número máximo de moléculas estructuradas de agua que producen mejores propiedades del producto, y que va a dividir partículas y a desarrollar las etapas de forma deseada cuando alcanza la presión del vapor del agua el punto crítico. En cambio, a baja temperatura se maximizará los cambios de gibbsite. Las imágenes de FESEM mostraron que la fase precursora forma diferentes morfologías de productos, como nanodimensionales, co-continuas como corales o partículas sueltas rodeadas de macroporos.

Ardabil, now known as one of the provinces of the country, has been one of the oldest and ancient cities in various historical periods, including Islam. This province comes to the end of the majesty and power during the reign of Safavid. Tombstone is among the heritage of the past that reflects culture and civilization. The existence of a tombstone on the tombs of Islamic period has always been observed in all parts of Iran. Though this issue exists in most cultures, it has always been considered by Muslims as an indicator of burial in the culture of the Islamic era and of Iran. The purpose of this research is to identify and study tombstone in the relevant area during the Safavid period. According to the results, the status of Shia religion can be clearly seen in all the tombstones of the Safavid period of Ardabil. In fact, it can be said that the combination of art and belief has caused the tombs of stone to be of particular importance and variety, and the line drawn on them represents the beliefs and cultures, as well as the scope of the literature of this region. Most of the designs include Islamic designs, flowers and leaves, animal designs and Quranic verses. The method used in this study is based on field study.

Personal branding is one of the newest topics in branding. It means that each person can have a stable personal brand by considering his/her given goals and using proper strategies. In this paper, the authors have tried to present a framework for personal brand positioning. To achieve this aim, a desk research was performed using meta/synthesis and experts’ poll to extract effective factors and indexes including strategy-based, capability-based, differentiation-based, audience-based, and performance-based dimensions. To measure and evaluate the indexes of framework dimension, a questionnaire was given to and completed by 200 experts in branding field. Questionnaire reliability was measured to be 0.854 by Cronbach's alpha. To evaluate the validation of the questionnaire, content validation method was used. The data was analyzed using structural equations modeling and LISREL software to represent the final framework. The results showed that the framework is well fitted for determining personal brand positioning and the pertaining indexes. Keywords: Personal branding, Personal brand, Brand positioning, Personal brand positioning, JEL Classification: M370, M310

This study was an attempt to examine Iranian EFL learners’ realization of the condolence speech act in English and to compare their realization with English native speakers’ (NSs) realization patterns. The study was further interested in investigating whether Iranian EFL learners’ realization of the condolence speech act is associated with their level of L2 proficiency. To this end, a Discourse Completion Test (DCT) was administered to 82 undergraduate Iranian EFL students in English. The participants were divided into three levels of language proficiency (elementary level, intermediate level, and advanced level) based on their scores on the Oxford Quick Placement Test (OQPT). For baseline comparisons, the EFL learners also received the translated version of the same DCT in Persian, and the English DCT was administered to 20 NSs of American English. The data were analyzed based on Elwood’s (2004) coding scheme. The results revealed that Iranian EFL learners had access to the same condolence strategies as English NSs, yet they differed in the semantic formulas, content, or forms they adopted to formulize their condolence expressions. In addition, level of L2 proficiency was found to be associated with Iranian EFL learners’ realization of the condolence speech act.

BACKGROUND: Laryngeal mask airway is still accompanied by complications such as sore throat. In this study, effects of three methods of reducing postoperative sore throat were compared with the control group. METHODS: 240 patients with ASA I, II candidates for cataract surgery were randomly divided into four same groups. No supplementary method was used in the control group. In the second, third and fourth groups, lidocaine gel, washing cuff before insertion, and washing mouth before removing laryngeal mask airway were applied, respectively. Anesthesia induction was done with fentanyl, atracurium, and propofol and maintained with propofol infusion. The incidence of sore throat was evaluated during the recovery, 3-4 h later and after 24 h using verbal analog scale. The data were analyzed by t-test, analysis of variance and chi-square using SPSS V11.5. RESULTS: Age, gender, duration of surgery and cuff pressure were the same in all the four groups. Incidence of sore throat at recovery room was highest in the control group (43.3%) and lowest in the washing mouth group (25%). However, no significant statistical difference was observed between these four groups (recovery, p = 0.30; discharge, p = 0.31; examination, p = 0.52). In this study, increased duration of operation had a significant relationship with the incidence of sore throat (p = 0.041). CONCLUSION: Sore throat is a common postoperative problem, but no special method has been found completely efficient yet. In this study, cuff washing, lidocaine gel, and mouth washing before removing laryngeal mask airway were not helpful for sore throat.

High knowledge and technology are rapidly becoming a competitive advantage in today’s world. Individual industries are considered one of the key sectors in the country’s industry. Ranking the factors that affect these industries makes us more familiar with their effectiveness and helps us take actions to improve such factors in knowledge-based companies. Consequently, based on previous research studies on Individual Industries, field observations, and a questionnaire prepared by the researchers, the current study explores and classifies the factors affecting the establishment of these industries. Regarding its purpose, this is an applied research, and regarding data collection, it is a descriptive survey. Using purposive sampling, 60 questionnaires were collected and effective factors were classified applying the SPSS software and the TOPSIS technique. This study suggests that content factors are ranked first place, while contextual and structural factors are ranked second and third, respectively. Therefore, executives and managers in single industries are recommended to strengthen joint enterprise norms and dominant values and beliefs in knowledge-based companies in order to help the growth and development of single industries.