In this article, an attempt has been made to estimate the amount of sound transmission loss in a flat oval channel by applying the approach of statistical energy analysis. Correct estimation of sound transmission loss in an air conditioning channel is of great importance due to the harmful effects of noise pollution in the environment on human health. Simulation with the statistical energy analysis method is a powerful approach to estimate sound and vibration in problems in which we deal with complex and multi-part systems; is considered. In this method, first, a system is divided into several subsystems, and then by writing a matrix equation that includes the energy exchanges between subsystems and energy loss coefficients; It is investigated from the perspective of vibration and sound estimation.On average, the model presented in this research is able to estimate the sound transmission loss in different dimensions of the air conditioning channels according to the experimental results in the accuracy range of ± 2.5 dB. Considering that it seems that the results obtained from modeling with this method are in good agreement with the experimental data; The results of this research can be used as an efficient approach to estimate noise in oval shaped channels stretched in different lengths.

Air pollution is one of the environmental challenges of today's world in most major cities. Considering the importance of atmospheric conditions in the occurrence of air pollution, this study was conducted to investigate the relationship between urban pollution and atmospheric conditions of Tabriz. At first, 32 air pollution periods (125 days) were identified in Tabriz by studying changes in PM10, CO and SO2 during 2008-2013. In order to create the database, 12 effective climate variables were collected at the mentioned days, and their correlation with the changes in the concentration of pollutants were investigated through descriptive analysis, Pearson correlation statistics and stepwise regression. The descriptive analysis of the values of the sustainability indices showed that the KI index in 12% of the cases and the TTI index in the 17-day period was between relatively unstable and relatively stable range, and in the rest of the cases, there was complete stability. The horizontal visibility proved to be between 600 and 10000 m, while the air temperature was between 12. 6 to 21. 7 Tº C, which fell down to below zero at 37 days. Surface pressure in 91% of days was more than 1015 hpa, and the maximum daily wind speed in 64% cases was less than 5 m/s. A quantitative analysis of the inversion layer characteristics indicated that its Δ T average with 4. 89 Tº C is in intensive category...

Background: The expansion of the use of audio and video media technology has faced society with many medical, cultural and economic challenges. In the meantime, excessive use of mobile phones can cause many problems. Objective: The aim of this study was to construct and validate a questionnaire on physical and psychological injuries of mobile phones. Method: The method of the present study was descriptive-correlational and confirmatory factor analysis. The statistical population of the study consisted of all citizens of Khorramabad with a diploma or higher in 1399, which was selected as a statistical sample by available sampling method of 200 people online and virtual. Results: The results showed that the factorized physical and psychological harm questionnaire of cell phone with 42 questions and 10 components (fear of loss, vibration syndrome, duck syndrome, nomophobia, insomnia, hearing problem, eye syndrome, tunnel and neck syndrome SMS) and has good reliability, validity and flexibility in terms of psychometrics. Discussion and Conclusion: The questionnaire of factor analysis of physical and psychological injuries of mobile phones can be used to identify and study the physical and psychological injuries of mobile phones.

Introduction and purpose: Despite recent efforts to identify microplastics in the aquatic environment worldwide, identifying the various sources of its release remains a challenging task. Understanding and identifying the different sources of aquatic pollution and the processes affecting them is essential for a comprehensive description of the quality of water resources. The aim of this study is therefore to introduce statistical methods to determine the sources of microplastics in aquatic environments. Methods: This review article first identifies the pathways of microplastic entry into the aquatic environment, followed by an examination of four commonly used multivariate statistical methods: Principal Component Analysis (PCA), Cluster Analysis (CA), Hierarchical Cluster Analysis (HCA) and Positive Matrix Factorization (PMF). Results: Multivariate statistical analysis can be used to determine different variables such as size, shape, color, and density of microplastics. It can also determine the sources of microplastics (domestic wastewater, industrial effluents, agricultural activities, surface runoff, air currents, etc.). It also identifies which variables have the greatest impact on pollution and suggests the best solutions to reduce pollution. Conclusion: the study of pollution based on multivariate statistical analysis can provide important information on the main sources of microplastic pollution and the relative contribution of different sources in the aquatic environment, which can help to improve environmental management and reduce pollution.

Sluggish Cognitive Tempo is used to describe a particular type of attention deficit, concentration, and slowness in information processing. The aim of this study was to investigate the psychometric properties of the Sluggish Cognitive Tempo Scale (SCTS) of the parent form among Iranian children. The present study is a descriptive study. A sample of 1700 people was selected from the provinces of Tehran, East Azerbaijan, West Azerbaijan, Kurdistan, Fars and Khorasan using cluster sampling method. 122 subjects were excluded from statistical analysis due to incomplete answers to the questionnaires and thus the final sample was reduced to 1578 parents. The confirmatory factor analysis method and internal consistency were used to compute the Sluggish Cognitive Tempo Scale factorial validity and reliability, respectively. Also, in order to examine the construct validity of the Sluggish Cognitive Tempo Scale, we computed correlations between different dimensions of Sluggish Cognitive Tempo Scale with Attention Deficit Subscale of Mental Health Assessment Questionnaire for Children and Adolescents. The results of statistical results showed that this scale has structural validity, criterion and convergence in Iranian society. The results indicate that the scale is three factors and also the validity of the scale using Cronbach's alpha method and retest test after Approved two weeks. According to the findings of the present study, the parent form of the Sluggish Cognitive Tempo Scale (SCTS) has a good validity and reliability and it can be used in research related to slow cognitive multiplication in Iranian society.

As the most complex manufactured structures, cities face excessive population growth. Their expansion has intensified on high-risk sites, and the available evidence also indicates the continuous increase of all types of natural crises in terms of intensity and frequency. Scientific and experimental findings show that the best way to deal with danger is to promote the resilience of settlements in different dimensions (social, economic-livelihood, physical-spatial and institutional); in other words, resilience in both human and environmental dimensions comprehensively. It decreases and increases. This research has evaluated and analyzed the components of resilience in Sari. The method of the present study is applied in terms of purpose and descriptive-analytical and field in nature. The statistical population in this research includes citizens living in the four districts of Sari, and the sample size was determined based on Cochran's formula of 383 people, who were selected from among the statistical population by stratified sampling. The questionnaire is the method of collecting library and field information and its most important tool. For data analysis, descriptive and inferential statistics (one-sample t-test and structural equation modeling) were used by SPSS and Smart PLS software, and entropy and SAW models were exerted. The research results indicate that the situation of the four regions of Sari regarding social components has better conditions than other dimensions of resilience. In terms of institutional components, they have a vulnerable state. According to the entropy model, among the components of resilience, the institutional dimension has the most weight, and the economic dimension has the least weight. Moreover, according to the SAV model, Region 1 ranks first, and Region 3 of Sari ranks last in having the components of resilience dimensions.

AbstractThe aim of this study was to investigate the validity, reliability and factor structure of the "How I Think" questionnaire to assess cognitive distortions in Iranian students. The present research design is descriptive and psychometric studies. The statistical population of this study included all male high school students in city Dezful in the academic year 1399-1400, from which 316 students were selected by multi-stage random sampling and completed the How I think and Bass and Perry Aggression Questionnaires (for Convergent validity). Factor analysis, Cronbach's alpha and Pearson correlation were used to analyze the data using SPSS and AMOS 20 software. The results of factor analysis showed that the questionnaire consists of six factors and has good fit indices. The convergent validity of this questionnaire indicated a satisfactory correlation between the dimensions of the scale "How I think" with the Aggression Questionnaire (p <0.01). Cronbach's alpha and Split- half coefficients for the whole scale and its dimensions ranged from 0.66 to 0.92.The conclusion is that the Persian version of the "How do I think" questionnaire for measuring cognitive distortions in Iranian students has acceptable psychometric properties and can be used as a valid tool in research, educational and clinical situations.

Dear Editor, We are thankful to the referees Dr. Mohamad Amin Pourhoseingholi et al. and the Editor for pointing out some valuable suggestion and important notes needed in the manuscript. The major concern of reviewer was about the positive Hepatitis D patient. Due to high number of cases in our study, the prevalence of Hepatitis D is very low.1) The only positive Hepatitis D is a 31 year-old woman. We have mentioned that she was an Afghanian lady but we have considered her native because she has Iranian ID Card, although we have not assessed her ancestry.2) As the reviewer has mentioned, chi square test is impractical in the present study so fisher exact test is used. We have mentioned to this important note in the methods and conclusion sections.3) It has mentioned that repeated test is performed to assess association between Hepatitis D and Tatto. So P value of likelihood ratio is not reported and both of P values are related to fisher exact test.