Publications by authors named "Mehdi Dehestani"

Super absorbent polymer (SAP) has a capacity to enhance the characteristics of cementitious composites in both their fresh and hardened forms. However, it is essential to recognize that the strength of SAP concrete may decrease. By altering the concrete composition and selecting the appropriate type of SAP, it is possible to reduce this reduction.

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By conducting an analysis of chloride migration in concrete, it is possible to enhance the durability of concrete structures and mitigate the risk of corrosion. In addition, the utilization of machine learning techniques that can effectively forecast the chloride migration coefficient of concrete shows potential as a financially viable and less complex substitute for labour-intensive experimental evaluations. The existing models for predicting chloride resistance encounter two primary challenges: the constraints imposed by a limited dataset and the absence of certain input variables.

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Due to the Covid-19 pandemic, using large amounts of personal protective equipment (PPE) throughout the world has extensively increased in recent years. The lack of a practical method to dispose of these recycled materials is one of the main concerns of researchers. Hence, comprehensive experimental tests were conducted in the present study to investigate the feasibility of using disposable gloves in mortars to achieve a sustainable mixture.

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This study provides a more profound understanding of the influence of the phases of fiber-reinforced recycled-aggregate concrete (FRRAC), on its elastic properties, in particular Young's modulus and Poisson's ratio. Multi-scale modeling analyses of mortar and FRRAC were conducted to assess the effect of variations in the fiber content, fiber elastic modulus, RA content, and water-to-cement ratio (w/c) on the elastic properties at each scale. Thus, the analytic Mori-Tanaka (MT) homogenization algorithm developed in Python programming language and the three-dimensional finite element (FE) homogenization scheme were applied to evaluate the elastic properties of FRRAC.

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In recent years, the overuse and exploitation of coal resources as fuel in industry has caused many environmental problems as well as changes in the ecosystem. One way to address this issue is to recycle these materials as an alternative to aggregates in concrete. Recently, non-destructive tests have also been considered by the researchers in this field.

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In this study, 3D finite element analyses (FEA) are conducted to quantify the orthotropic elastic properties and investigate the load transfer mechanism of bone at the sub-lamellar level. Three finite element (FE) unit cells with periodic boundary conditions are presented to model a two-scale microstructure of bone including a mineralized collagen fibril (MCF), the extrafibrillar matrix (EFM) and the resulting fibril array (FAY) under arbitrary loading. The axial and transverse elastic properties of the FAY computed by FEA are calibrated with unique experimental results on ovine micro-samples showing a coherent fibril orientation.

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Objective: The aim of this study was to compare marital satisfaction between parents of children with attention deficit hyper activity disorder (ADHD) and parents of normal children.

Method: In this study we have selected 400 parents (200 parents of children with ADHD and 200 parents of normal children), whose children age range was 6-18 years. Data were collected using Enrich marital satisfaction Questionnaire, Kiddie Schedule for Affective Disorders and Schizophrenia Present and Lifetime Version (K-SADS-PL) and Conner's Questionnaire (parent and self-report forms).

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The objective of the study was to compare the attention-deficit/ hyperactivity, and substance abuse disorders background in the parents of children with attention-deficit/ hyperactivity disorder (ADHD), and the parents of normal children. The available sampling method was used to choose 400 parents of children (200 parents of children with ADHD and 200 parents of normal children), the ages of children were 6-18 years old. The data were collected through the Schedule for Affective Disorders and Schizophrenia (SADS) for parents and the Kiddy Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version (K-SADS-PL), Connors Adult ADHD Rating Scale (CAARS) and the Wender Utah Rating Scale (WURS) for adult ADHD.

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Background: Addiction as a biopsychosocial problem has been dramatically increased in our country. Adverse consequences of the addiction in women have been shown to be more than men, which in turn can affect family members' health and wellbeing. The current study examined the efficacy of stress coping skills training in addicted women referring to an outpatient centre of addiction prevention located in Welfare Organization of Gorgan, Iran.

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