69 research outputs found

    Applications of Dynamic Mode Decomposition and Sparse Reconstruction in the Data-Driven Dynamic Analysis of Physical Systems

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    Recent advancements in data collection methods and equipment have resulted in a huge increase in the amount of data collected by observing various types of physical phenomena. Regardless of the amount of data collected, it is well known for many physical systems, the so-called information rank of the collected data is much lower than the rank of the data itself. This usually means the data may be represented sparsely in terms of a properly-chosen basis. This realization has led to methods for storing large amounts of data through compression by sacrificing negligible data quality. More importantly, with the advent of compressed sensing techniques, using an appropriate representation basis and sampling technique, it is now possible to sample data far below the Shannon-Nyquist limit thus speeding up data acquisition and also reducing the complexity of data-acquisition hardware. In this research, we explore the application of various modern data analysis techniques such as proper orthogonal decomposition (POD), dynamic mode decomposition (DMD), compressed sensing, and Kalman filter and smoother in the data-driven analysis of dynamic systems with many degrees of freedom. This research has resulted in four novel methods. The first method is developed for denoising and spatial resolution enhancement of 4D-Flow MRI data based on POD and sparse reconstruction. The second method combines DMD and compressed sensing and takes discrete cosine transform (DCT) as the representation basis for dynamic denoising and gappy data reconstruction in 2D. The third method is a fast and parameter-free dynamic denoising method which combines a reduced-order model (ROM), a Kalman filter and smoother, and a DMD-based forward model. The fourth method is developed for reconstructing a 2D incompressible flow field by taking sparse measurements from the Fourier domain. As the reconstruction basis, a custom divergence-free set of basis vectors are derived and implemented

    Integration of fuzzy Shannon’s entropy with fuzzy TOPSIS for industrial robotic system section

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    Purpose: The aim of this study is applying a new method for Industrial robotic system selection. Design/methodology/approach: In this paper, the weights of each criterion are calculated using fuzzy Shannon’s Entropy. After that, fuzzy TOPSIS is utilized to rank the alternatives. Then we select the best Industrial Robotic System based on these results. Findings and Originality/value: The outcome of this research is ranking and selecting industrial robotic systems with the help of Fuzzy Shannon’s Entropy and Fuzzy TOPSIS techniques. Originality/value: This paper offers a new integrated method for industrial robotic system selection.Peer Reviewe

    A study on the relationship between Tabriz high school teachers’ sense of efficacy and their educational quality

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    For many years, one of the main aims of pedagogy is the promotion of educational quality. Any impressive achievement in educational quality and pedagogy needs to be active participation and support by teachers. Considering the important role of the teacher in promotion of educational quality, this study was to investigate the relationship between Tabriz high school teachers’ senses of efficacy and their educational quality to shed some lights on the blurred issues in this regard. To this end 60 high school teachers (30 psychology teachers and 30 physics teachers) were selected from the population of study. For assessing educational quality, Flanders Interaction Analysis Category, and for evaluating teachers' sense of efficacy, Ohio Teacher Sense of Efficacy Scale was used. The results of Canonical correlation indicated that only one root of analysis was significant and from the predictor variables, teacher sense of efficacy is significantly related to the indirect to direct teaching method and teacher- student reactions

    A study on the relationship between Tabriz high school teachers’ sense of efficacy and their educational quality

    Get PDF
    For many years, one of the main aims of pedagogy is the promotion of educational quality. Any impressive achievement in educational quality and pedagogy needs to be active participation and support by teachers. Considering the important role of the teacher in promotion of educational quality, this study was to investigate the relationship between Tabriz high school teachers’ senses of efficacy and their educational quality to shed some lights on the blurred issues in this regard. To this end 60 high school teachers (30 psychology teachers and 30 physics teachers) were selected from the population of study. For assessing educational quality, Flanders Interaction Analysis Category, and for evaluating teachers' sense of efficacy, Ohio Teacher Sense of Efficacy Scale was used. The results of Canonical correlation indicated that only one root of analysis was significant and from the predictor variables, teacher sense of efficacy is significantly related to the indirect to direct teaching method and teacher- student reactions

    Three classifications on branching processes and their behavior for finding the solution of nonlinear integral equations

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    In this paper, we consider the Monte Carlo method for finding the solution of nonlinear integral equations at a fixed point xo‐ In this method, simulated Galton‐Watson branching process is employed for solving the proposed integral equation. The main goal of this paper is to compare the behavior of three classifications of branching process based on the mean progeny, i.e. the subcritical, critical and supercritical process. First published online: 09 Jun 201

    Studying the environmental health status of beauty salons of Kashan

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    Background and aims: Beauty salons are considered as the places which the environmental health and renovation are adhered too. they can improve the society’s health and influence controlling the diseases. Not considering this issue causes the spread of skin and hair diseases and infections and louse. This study was aimed to determine the health status of beauty salons of Kashan in 2014. Methods: This descriptive-analytical study was done in 2014 in Kashan. Out of 320 beauty salons in Kashan, 220 were selected at random. Collecting the data was through observation, interview, filling the questionnaires and check lists in the beauty salons. Data collection was done on the basis of the environmental health evaluation form for beauty salons. The check list related to each beauty salon was completed and the data were analyzed by SPSS software. Results: The results of this study showed that 45.5 of the salon employees had participated in the special course of public health and 54.5 had personal health card. Fifty one point four percent of them were acceptable in terms of personal hygiene and 52.7 shared the tools and equipment. Half of the beauty salons had been sanitized and 52.3 of them had soaps and towels. Conclusion: The results showed that the beauty salons in Kashan had acceptable building status. Some personal hygiene factors such as personal health card, public health certificate and observing personal hygiene needs more training. Also, more supervision and inspection must be carried out by the environmental health experts

    A Preliminary Study on the Therapeutic Effects of Hydroxychloroquine on Generalized Vitiligo

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    Vitiligo is a recalcitrant depigmentary autoimmune skin disorder. Hydroxychloroquine (HCQ) is an effective immunomodulatory drug which is widely used in treatment of autoimmune disorders. HCQ-induced pigmenta- tion has been previously found in patients taking HCQ due to other auto- immune diseases. The present study aimed to determine whether HCQ im- proves re-pigmentation of generalized vitiligo. HCQ was orally administered 400 mg daily (6.5 mg/Kg of body weight) by 15 patients with generalized vitiligo (more than 10% involvement of body surface area) for three months. Patients were evaluated monthly and skin re-pigmentation was assessed us- ing the Vitiligo Area Scoring Index (VASI). Laboratory data were obtained and repeated monthly. Fifteen patients (12 women and 3 men) with a mean age of 30.13±12.75 years were studied. After 3 months, the extent of re-pigmen- tation on all the body regions, including the upper extremities, hands, trunk, lower extremities, feet, and head and neck was significantly higher than the baseline (P value <0.001, 0.016, 0.029, <0.001, 0.006, 0.006, respectively). Patients with concomitant autoimmune diseases had significantly more re- pigmentation compared with others (P=0.020). No irregular laboratory data were observed during the study. HCQ could be an effective treatment for generalized vitiligo. The benefits are likely to be more evident in case of con- comitant autoimmune disease. The authors recommend additional large- scale controlled studies to draw further conclusions

    A Preliminary Study on the Therapeutic Effects of Hydroxychloroquine on Generalized Vitiligo

    Get PDF
    Vitiligo is a recalcitrant depigmentary autoimmune skin disorder. Hydroxychloroquine (HCQ) is an effective immunomodulatory drug which is widely used in treatment of autoimmune disorders. HCQ-induced pigmenta- tion has been previously found in patients taking HCQ due to other auto- immune diseases. The present study aimed to determine whether HCQ im- proves re-pigmentation of generalized vitiligo. HCQ was orally administered 400 mg daily (6.5 mg/Kg of body weight) by 15 patients with generalized vitiligo (more than 10% involvement of body surface area) for three months. Patients were evaluated monthly and skin re-pigmentation was assessed us- ing the Vitiligo Area Scoring Index (VASI). Laboratory data were obtained and repeated monthly. Fifteen patients (12 women and 3 men) with a mean age of 30.13±12.75 years were studied. After 3 months, the extent of re-pigmen- tation on all the body regions, including the upper extremities, hands, trunk, lower extremities, feet, and head and neck was significantly higher than the baseline (P value <0.001, 0.016, 0.029, <0.001, 0.006, 0.006, respectively). Patients with concomitant autoimmune diseases had significantly more re- pigmentation compared with others (P=0.020). No irregular laboratory data were observed during the study. HCQ could be an effective treatment for generalized vitiligo. The benefits are likely to be more evident in case of con- comitant autoimmune disease. The authors recommend additional large- scale controlled studies to draw further conclusions

    INVESTIGATING THE RELATIONSHIP BETWEEN CORPORATE SOCIAL RESPONSIBILITY AND FINANCIAL PERFORMANCE OF CONSTRUCTION, ARCHITECTS AND INDUSTRIAL COMPANIES IN THE MUNICIPALITIES OF MAZANDARAN PROVINCE

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    Abstract. The purpose of this research was to investigate the relationship between corporate social responsibility and financial performance of construction, architecture and industrial companies in the municipalities of Mazandaran province. This research is descriptive-correlative method and is of applied research type. The statistical population of the study consisted of all construction, architectural and industrial companies in the municipalities of Mazandaran province during 2013 to 2017, in which 50 companies were studied. The data of the research were extracted from the financial statements of the companies and analyzed using regression models using combination data. The research findings showedthat there is a positive and significant relationship between corporate social capital and asset returns and earnings per share of companies, and there is not a significant relationship between corporate social capitals with equity returns.Keywords: Social Responsibility, Financial Performance, Returns on Assets, Return on Equity, Earnings perShare

    Measurement invariance of the General Health Questionnaire (GHQ-12) across gender and age: Demographic and medical correlates of mental health in patients with COVID-19

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    Introduction: The present cross sectional study aimed to evaluate the construct and criterion validity, reliability, and gender and age differences of the 12-item General Health Questionnaire (GHQ-12) among hospitalized patients with COVID-19 in 2020. The criterion validity was assessed via its link with perceived stress, sleep quality, daily life activities, and demographic and medical characteristics. Methods: A total of 328 COVID-19 patients (55.8% men; Mage = 50.49, SD = 14.96) completed the GHQ-12, the Perceived Stress Scale (PSS), the Pittsburgh Sleep Quality Index (PSQI), the Activities of Daily Life (ADL)-Katz Scale, and the Lawton Instrumental Activities of Daily Living Scale (IADL). Results: Among 13 factorial models, the three-factor model (successful coping, self-esteem, and stress) was shown to have the best fit. GHQ-12 was positively associated with PSQI, PSS, Hyperlipidemia, psychiatry disorders, hospitalization duration, the change in sleep time, and use of sleeping pills, and negatively correlated with educational level, and the number of family members. The GHQ-12 also had a negative correlation with ADL and IADL in over 60 years of age group. Females scored higher on total GHQ-12 scores, compared to males. Finally, the hospitalization duration was longer for patients over 60 (mean = 8.8 days, SD = 5.9) than patients under 60 (mean = 6.35 days, SD = 5.87). Discussion: Overall, the findings provided evidence that mental distress in patients with COVID-19 is correlated with high perceived stress, low sleep quality, low ADL and IADL, and a range of demographic features and medical conditions. Designing psychological interventions for these patients that target the aforementioned correlates of mental distress is warranted.publishedVersio
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