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Benjamini-Schramm convergence of periodic orbits [article]

Amir Mohammadi, Kasra Rafi
2021 arXiv   pre-print
We prove a criterion for Benjamini-Schramm convergence of periodic orbits of Lie groups. This general observation is then applied to homogeneous spaces and the space of translation surfaces.
arXiv:2108.07010v2 fatcat:sqx77c3xizgpfc4gwi5wclceoi

Modeling, Control, and Optimization of Multi-Generation and Hybrid Energy Systems

Kody M. Powell, Kasra Mohammadi
2021 Processes  
As renewable energy technologies decrease in cost and become more prevalent, there is an increasing trend towards electrification of many energy systems [...]
doi:10.3390/pr9071125 fatcat:nirmgqwpavdthpc3onefpqzxvu

An analysis of wind energy potential and economic evaluation in Zahedan, Iran

Ali Mostafaeipour, Mohsen Jadidi, Kasra Mohammadi, Ahmad Sedaghat
2014 Renewable & Sustainable Energy Reviews  
Most people would produce their own clean local energy if it were easy and affordable. When a renewable energy system is installed, there is an upfront cost that can be partially or completely offset by various ways. Purpose of this study is to assess wind energy potential for the city of Zahedan in southeast part of Iran. Five-year (2003Five-year ( -2007 wind data has been analyzed to obtain wind power density and wind energy potential. Weibull density function has been used to determine the
more » ... nd power density and energy of the region. Yearly mean Weibull parameters, k and c, were 1.155 and 3.401 (m/s). Obtained wind power and energy densities are 89.184 W/m 2 , and 781.252 kWh/m 2 respectively. In short, economic evaluation and analysis of four different wind turbines are presented in this paper. In order to utilize wind energy, it is recommended to install Proven 2.5 kW model wind turbine in the region which is the most cost efficient option.
doi:10.1016/j.rser.2013.11.016 fatcat:3kcwzkzcx5d3jpoq4bkv56ouum

Electricity Generation and Energy Cost Estimation of Large-Scale Wind Turbines in Jarandagh, Iran

Kasra Mohammadi, Ali Mostafaeipour, Yagob Dinpashoh, Nima Pouya
2014 Journal of Energy  
Mohammadi and Mostafaeipour [16] appraised the economic viability of installing 6 different wind turbines models in Aligoodarz situated in west part of Iran. Mostafaeipour et al.  ...  Mohammadi and Mostafaeipour [8] utilized different methods for comprehensive study of wind turbine utilization in Zarrineh, Iran. They used hourly, monthly, seasonal, and yearly wind data analysis.  ... 
doi:10.1155/2014/613681 fatcat:aoc6atil3zdw7nxifuycocriti

A support vector machine–firefly algorithm-based model for global solar radiation prediction

Lanre Olatomiwa, Saad Mekhilef, Shahaboddin Shamshirband, Kasra Mohammadi, Dalibor Petković, Ch Sudheer
2015 Solar Energy  
In this paper, the accuracy of a hybrid machine learning technique for solar radiation prediction based on some meteorological data is examined. For this aim, a novel method named as SVM-FFA is developed by hybridizing the Support Vector Machines (SVMs) with Firefly Algorithm (FFA) to predict the monthly mean horizontal global solar radiation using three meteorological parameters of sunshine duration ( n), maximum temperature (T max ) and minimum temperature (T min ) as inputs. The predictions
more » ... ccuracy of the proposed SVM-FFA model is validated compared to those of Artificial Neural Networks (ANN) and Genetic Programming (GP) models. The root mean square (RMSE), coefficient of determination (R 2 ), correlation coefficient (r) and mean absolute percentage error (MAPE) are used as reliable indicators to assess the models' performance. The attained results show that the developed SVM-FFA model provides more precise predictions compared to ANN and GP models, with RMSE of 0.6988, R 2 of 0.8024, r of 0.8956 and MAPE of 6.1768 in training phase while, RMSE value of 1.8661, R 2 value of 0.7280, r value of 0.8532 and MAPE value of 11.5192 are obtained in the testing phase. The results specify that the developed SVM-FFA model can be adjudged as an efficient machine learning technique for accurate prediction of horizontal global solar radiation.
doi:10.1016/j.solener.2015.03.015 fatcat:okulm6wycjclndgqtsdx7ftxla

Thermoeconomic Evaluation and Optimization of Using Different Environmentally Friendly Refrigerant Pairs for a Dual-Evaporator Cascade Refrigeration System

Kasra Mohammadi, Kody M. Powell
2021 Processes  
[24] and Mohammadi et al. [25] .  ... 
doi:10.3390/pr9101855 fatcat:tmomu4frffdkhetgcmgt6dcea4

Assessing different parameters estimation methods of Weibull distribution to compute wind power density

Kasra Mohammadi, Omid Alavi, Ali Mostafaeipour, Navid Goudarzi, Mahdi Jalilvand
2016 Energy Conversion and Management  
Mohammadi and Mostafaeipour [37] provided comparison between two parameters estimation methods namely empirical method and energy pattern factor method to determine more accurate method for analyzing  ... 
doi:10.1016/j.enconman.2015.11.015 fatcat:5b624sgje5fotljodzomot4nge

Expression of Concern: Application and economic viability of wind turbine installation in Lutak, Iran

Kasra Mohammadi, Ali Mostafaeipour, Ahmad Sedaghat, Shahaboddin Shamshirband, Dalibor Petković
2018 Environmental Earth Sciences  
This article contains overlap with (Mostafaeipour and Mohammadi 2015) (amongst others). All authors disagree with this editorial expression of concern.  ...  The Editors-in-Chief of Environmental Earth Sciences are issuing an editorial expression of concern to alert readers that this article (Mohammadi et al. 2016) shows substantial indication of irregularities  ... 
doi:10.1007/s12665-018-7996-z fatcat:jhubxntpr5dsjfkpqvvs5d4kby

Assessing wind energy potential in Kurdistan province, Iran

Saeed Jahanbakhsh Asl, Majid Rezaei Banafsheh, Yagob Dinpashoh, Marziyeh Esmaeilpour, Kasra Mohammadi, Ali Mohammad Khorshiddoust
2014 International Journal of Energy and Environmental Engineering  
In this study, 3-h wind speed data for years 1987-2009 at 10, 20 and 40 m heights have been analyzed for Kurdistan province. Wind energy potential at five stations in this province was investigated. Six types of methods, namely, graphical, empirical, method of moment, energy pattern factor, maximum likelihood and probabilityweighted moments were used to estimate the parameters. The results showed that MOM was an efficient method among others in the present study because it had the lowest value
more » ... f the Chi-square statistics. Also, wind speed for Tyear return period was estimated. In the annual time scale, the range of shape parameter, k, was between 0.78 and 1.03 whereas the range of the scale parameter, c, was between 1.84 and 4.37 m/s. Also, the most important characteristics of wind energy were evaluated. Among all the stations, Bijar and Zarineh Obato were found to be the best sites for wind energy harnessing. Bijar had the highest value of wind power density at 10 m height, which was equal to 308 W/m 2 . In average, the rank of stations according to 100 years return period was as: (1) Zarineh Obato, (2) Bijar, (3) Ghorveh, (4) Saghez and (5) Sanandaj.
doi:10.1007/s40095-014-0100-x fatcat:mw2gn37dbjc2larlrm2bhdggme

Retraction Note to: Temperature-based estimation of global solar radiation using soft computing methodologies

Kasra Mohammadi, Shahaboddin Shamshirband, Amir Seyed Danesh, Mohd Shahidan Abdullah, Mazdak Zamani
2020 Theoretical and Applied Climatology  
Environ Earth Sci (2016) 75: 172. [3] "Daily global solar radiation prediction from air temperatures using kernel extreme learning machine: A case study for Iran" by Shahaboddin Shamshirband, Kasra Mohammadi  ...  Theor Appl Climatol (2016) 125: 53. [5] "Support vector regression based prediction of global solar radiation on a horizontal surface" by Kasra Mohammadi, Shahaboddin Shamshirband, Mohammad Hossein Anisi  ... 
doi:10.1007/s00704-020-03153-z fatcat:kskgu3k6zfb2tcxsm74mmckhta

Wind Resource Assessment and Economic Viability of Conventional and Unconventional Small Wind Turbines: A Case Study of Maryland

Navid Goudarzi, Kasra Mohammadi, Alexandra St. Pé, Ruben Delgado, Weidong Zhu
2020 Energies  
Annual mean wind speed distribution models for power generation based on regional wind resource maps are limited by spatial and temporal resolutions. These models, in general, do not consider the impact of local terrain and atmospheric circulations. In this study, long-term five-year wind data at three sites on the North, East, and West of the Baltimore metropolitan area, Maryland, USA are statistically analyzed. The Weibull probability density function was defined based on the observatory
more » ... Despite seasonal and spatial variability in the wind resource, the annual mean wind speed for all sites is around 3 m/s, suggesting the region is not suitable for large-scale power generation. However, it does display a wind power capacity that might allow for non-grid connected small-scale wind turbine applications. Technical and economic performance evaluations of more than 150 conventional small-scale wind turbines showed that an annual capacity factor and electricity production of 11% and 1990 kWh, respectively, are achievable. It results in a payback period of 13 years. Government incentives can improve the economic feasibility and attractiveness of investments in small wind turbines. To reduce the payback period lower than 10 years, modern/unconventional wind harvesting technologies are found to be an appealing option in this region. Key contributions of this work are (1) highlighting the need for studying the urban physics rather than just the regional wind resource maps for wind development projects in the build-environment, (2) illustrating the implementation of this approach in a real case study of Maryland, and (3) utilizing techno-economic data to determine suitable wind harnessing solutions for the studied sites.
doi:10.3390/en13225874 fatcat:ve2s2x4refg3vex2jewpc26bbi

Expression of Concern: Influence of introducing various meteorological parameters to the Angström–Prescott model for estimation of global solar radiation

Kasra Mohammadi, Hossein Khorasanizadeh, Shahaboddin Shamshirband, Chong Wen Tong
2018 Environmental Earth Sciences  
This article contains overlap with Khorasanizadeh et al. (2013 Khorasanizadeh et al. ( , 2014 , Mohammadi et al. (2014) , Shamshirband et al. (2016) (amongst others).  ... 
doi:10.1007/s12665-018-7995-0 fatcat:s37bveqginal7chaftnizvzqhu

Mediator role of experiential avoidance in relationship of perceived stress and alexithymia with mental health

Ali Zakiei, Seyed Ramin Ghasemi, Nader Rajabi Gilan, Sohyla Reshadat, Kasra Sharifi, Omid Mohammadi
2017 Eastern Mediterranean Health Journal  
Rôle de médiation de l'évitement expérientiel dans le rapport entre stress perçu, alexithymie et santé mentale RÉSUMÉ La présente étude transversale a examiné le rôle de médiation de l'évitement expérientiel dans le rapport entre le stress perçu, l'alexithymie et la santé mentale. Nous avons inscrit dans cette étude 440 étudiants (âge compris entre 18 et 30 ans) de l'Université des Sciences médicales de Kermanshah par la méthode d'échantillonnage aléatoire stratifié. Les instruments utilisés
more » ... s l'étude étaient la liste de contrôle démographique, le questionnaire sur la santé générale en 28 items, l'échelle d'Alexithymie de Toronto à 20 items et l'échelle de mesure du stress perçu. Les données ont été analysées au moyen des logiciels SPSS-18 et AMOS-18 en recourant à la corrélation de Pearson, l'analyse de régression hiérarchique et la modélisation par équation structurelle. Il y avait une corrélation positive significative entre le stress perçu et l'évitement expérientiel, et l'alexithymie et les problèmes de santé mentale (p<0,001). La modélisation par équation structurelle a montré que la relation entre le stress perçu et les problèmes de santé mentale causés par l'évitement expérientiel était 0,19 [(β =0,19; erreur standard (ES)=0,09 ; p=0,001], et que la relation entre l'alexithymie et les problèmes de santé mentale causés par l'évitement expérientiel était 0,09 [(β =0,09; ES=0,43; p=0,001.] Le rôle de médiation de l'évitement expérientiel a été confirmé de telle sorte que les effets de l'alexithymie et du stress perçu diminuent.
doi:10.26719/2017.23.5.335 fatcat:gdvhj7spknbhzgticwgwhb3mqa

COVID-19-Related Acute Ischemic Stroke in Young Adults: What Is the Optimal Antithrombotic Regimen for Secondary Prevention?

Fahimeh Vahabizad, Maryam Sharifian Dorche, Pegah Mohammadi, Kasra Khatibi, Ashkan Mowla
2020 Journal of Neurology Research  
doi:10.14740/jnr616 pmid:33984101 pmcid:PMC8040460 fatcat:ipnm3pbiubeaxhea23wi56wiyq

Association between carotid intima-media thickness and ulcerative colitis: a systematic review and meta-analysis

Ladan Ladan Goshayeshi, Ali Bahari, Farnaz Torabian, Kasra Molooghi, Ermia Musavi Mohammadi, Mehrdad Sahranavard, Hoda Hosseinzadeh Maleki, Zahra Sabzeh Noughabi, Benyamin Hoseini
2018 Electronic Physician  
Early detection of atherosclerosis is an essential means of decreasing cardiovascular events and its associated mortality. Systemic inflammatory diseases such as ulcerative colitis (UC), are thought to be a contributing factor to atherosclerosis due to the rise of inflammatory cytokines. Objective: The aim of this systematic review and meta-analysis was to assess the association between atherosclerosis and UC. Methods: This systematic review and meta-analysis was performed in February 2017 with
more » ... no date restrictions. PubMed, Cochrane Library and Embase were searched to discover all available observational studies on atherosclerosis among UC patients. The STROBE criteria were used to assess the quality of the included articles. Heterogeneity was assessed by the I-square statistic and publication bias with funnel plot and Egger's regression test. Overall summary mean difference was calculated as study effect size using random effect model. Comprehensive Meta-Analysis Software version 2.2 was used to perform analyses. Results: A total of 5 articles met our eligibility criteria. We included a sum of 206 UC patients and 229 non-UC individuals in our review with a mean difference of c-IMT ranged from 0.03±0.0 to 0.16±0.03 mm, and a pooled mean difference of 0.127 mm (95% CI 0.058-0.195: I 2 =90.266%). Potential publication bias did not exist for the UC. Conclusion: Our findings showed significant differences in carotid intima-media thickness among UC and Non-UC groups, making c-IMT a viable choice as a predicting marker for atherosclerosis. Thus, we suggest that policy makers assess and consider its application in future protocols for the follow up and management of UC patients.
doi:10.19082/6956 pmid:30034664 pmcid:PMC6049966 fatcat:uzu3lw67tbgm3ltbz37g2pvgcu
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