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Fault ride-through capability improvement in a DFIG-based wind turbine using modified ADRC

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Protection and Control of Modern Power Systems 2022年第1期7卷 751-787页

作者： seyed reza Mosayyebi seyed Hamid Shahalami Hamed Mojallali Electrical Engineering Department Faculty of EngineeringUniversity of GuilanRashtIran

In this paper,an overview of several strategies for fault ride-through(FRT)capability improvement of a doubly-fed induction generator(DFIG)-based wind turbine is *** and parameter variations have adverse effects on the performance of these *** is desirable to use a control method that is robust to such *** disturbance rejection control(ADRC)is one of the most common methods for eliminating the effects of *** improve the performance of the conventional ADRC,a modified ADRC is introduced that is more robust to disturbances and offers better *** non-derivability of the fal function used in the conventional ADRC degrades its efficiency,so the modified ADRC uses alternative functions that are derivable at all points,i.e.,the odd trigonometric and hyperbolic functions(arcsinh,arctan,and tanh).To improve the effciency of the proposed ADRC,fuzzy logic and fractional-order functions are used *** fuzzy fractional-order ADRC(FFOADRC),all disturbances are evaluated using a nonlinear fractional-order extended state observer(NFESO).The performance of the suggested structure is investigated in MATLAB/*** simulation results show that during disturbances such as network voltage sag/swell,using the modified ADRCs leads to smaller fluctuations in stator flux amplitude and DC-link voltage,lower variations in DFIG velocity,and lower total harmonic distortion(THD)of the stator *** demonstrates the superiority over conventional ADRC and a proportional-integral(PI)***,by chang-ing the crowbar resistance and using the modified ADRCs,the peak values of the waveforms(torque and currents)can be controlled at the moment of fault occurrence with no significant distortion.

关键词： Doubly-fed induction generator(DFIG) Auto disturbance rejection control(ADRC) Fault ride-through(FRT) Wind turbine Nonlinear fractional-order extended state observer(NFESO)

A novel hybrid algorithm based on a harmony search and artificial bee colony for solving a portfolio optimization problem using a mean-semi variance approach

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Journal of Central South University 2016年第1期23卷 181-188页

作者： seyed mohammad seyedhosseini mohammad Javad Esfahani Mehdi Ghaffari Department of Industrial Engineering Iran University of Science and Technology Young Researchers and Elite Club Naragh BranchIslamic Azad University Department of Industrial Engineering Naragh BranchIslamic Azad University

Portfolio selection is one of the major capital allocation and budgeting issues in financial management, and a variety of models have been presented for optimal selection. Semi-variance is usually considered as a risk factor in drawing up an efficient frontier and the optimal portfolio. Since semi-variance offers a better estimation of the actual risk portfolio, it was used as a measure to approximate the risk of investment in this work. The optimal portfolio selection is one of the non-deterministic polynomial(NP)-hard problems that have not been presented in an exact algorithm, which can solve this problem in a polynomial time. Meta-heuristic algorithms are usually used to solve such problems. A novel hybrid harmony search and artificial bee colony algorithm and its application were introduced in order to draw efficient frontier portfolios. Computational results show that this algorithm is more successful than the harmony search method and genetic algorithm. In addition, it is more accurate in finding optimal solutions at all levels of risk and return.

关键词： portfolio optimizations mean-variance model mean semi-variance model harmony search and artificial bee colony efficient frontier

Contribution of tuned liquid column gas dampers to the performance of offshore wind turbines under wind, wave, and seismic excitations

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Earthquake Engineering and Engineering Vibration 2016年第3期15卷 551-561页

作者： Khosrow Bargi reza Dezvareh seyed Amin Mousavi School of Civil Engineering College of Engineering University of Tehran

The main intention of the present study is to reduce wind, wave, and seismic induced vibrations of jacket- type offshore wind turbines （JOWTs） through a newly developed vibration absorber, called tuned liquid column gas damper （TLCGD）. Using a Simulink-based model, an analytical model is developed to simulate global behavior of JOWTs under different dynamic excitations. The study is followed by a parametric study to explore efficiency of the TLCGD in terms of nacelle acceleration reduction under wind, wave, and earthquake loads. Study results indicate that optimum frequency of the TLCGD is rather insensitive to excitation type. In addition, while the gain in vibration control from TLCGDs with higher mass ratios is generally more pronounced, heavy TLCGDs are more sensitive to their tuned frequency such that ill-regulated TLCGD with high mass ratio can lead to destructive results. It is revealed that a well regulated TLCGD has noticeable contribution to the dynamic response of the JOWT under any excitation.

关键词： offshore wind turbine wind load wave load seismic load tuned liquid column gas damper

The Nuclear Factor KappaB(NF-kB)signaling in cancer development and immune diseases

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Genes & Diseases 2021年第3期8卷 287-297页

作者： mohammad reza Zinatizadeh Bettina Schock Ghanbar Mahmoodi Chalbatani Peyman Kheirandish Zarandi seyed Amir Jalali seyed Rouhollah Miri Cancer Research Center Shahid Beheshti University of Medical SciencesTehran***Iran Centre for Experimental Medicine Queen’s University BelfastBelfastBT71NNUnited Kingdom Department of Medical Immunology School of MedicineTehran University of Medical SciencesTehran***Iran Cancer Research Center Cancer Institute of IranTehran University of Medical ScienceTehran***Iran Department of Medical Immunology School of MedicineShahid Beheshti University of Medical SciencesTehran***Iran

The nuclear factor kappa B(NF-kB)family of transcription factors plays an essential role as stressors in the cellular environment,and controls the expression of important regula-tory genes such as immunity,inflammation,death,and cell ***-kB protein is located in the cytoplasm,and can be activated by various cellular *** are two path-ways for NF-kB activation,as the canonical and non-canonical pathways,which require com-plex molecular interactions with adapter proteins and phosphorylation and ubiquitinase ***,this increases NF-kB translocation in the nucleus and regulates gene *** this study,the concepts that emerge in different cellular systems allow the design of NF-kB function in *** would not only allow the development for rare dis-eases associated with NF-kB,but would also be used as a source of useful information to elim-inate widespread consequences such as cancer or inflammatory/immune diseases.

关键词： Cancer Immunity Inflammation NF-kB Signaling

Application of computational fluid dynamics in design of viscous dampers-CFD modeling and full-scale dynamic testing

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Earthquake Engineering and Engineering Vibration 2023年第4期22卷 1065-1080页

作者： Hassan Lak seyed Mehdi Zahrai seyed mohammad Mirhosseini Ehsanollah Zeighami Department of Civil Engineering Collage of EngineeringArak BranchIslamic Azad UniversityArak ***Iran School of Civil Engineering College of EngineeringUniversity of TehranTehran ***Iran

Computational fluid dynamics(CFD)provides a powerful tool for investigating complicated fluid *** paper aims to study the applicability of CFD in the preliminary design of linear and nonlinear fluid viscous *** fluid viscous dampers were designed based on CFD *** first device was a linear viscous damper with straight *** second was a nonlinear viscous damper containing a one-way pressure-responsive valve inside its *** dampers were detailed based on CFD simulations,and their internal fluid flows were ***-scale specimens of both dampers were manufactured and tested under dynamic *** to the tests results,both dampers demonstrate stable cyclic behaviors,and as expected,the nonlinear damper generally tends to dissipate more energy compared to its linear *** compatibility was achieved between the experimentally measured damper force-velocity curves and those estimated from CFD *** a thermography camera,a rise in temperature of the dampers was measured during the *** was found that output force of the manufactured devices was virtually independent of temperature even during long duration ***,temperature dependence can be ignored in CFD models,because a reliable temperature compensator mechanism was used(or intended to be used)by the damper manufacturer.

关键词： fluid viscous damper passive control dynamic testing energy dissipation device computational fluid dynamic thermography

Chest computed tomography findings of COVID-19 in children younger than 1 year: a systematic review

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World Journal of Pediatrics 2021年第3期17卷 234-241页

作者： Alireza Ghodsi Moniba Bijari seyed Ali Alamdaran Amin Saberi Elnaz Mahmoudabadi mohammad reza Balali Sara Ghahremani Student Research Committee Faculty of MedicineMashhad University of Medical SciencesMashhadIran Radiology Department Faculty of MedicineMashhad University of Medical SciencesMashhadIran Faculty of Medicine Mashhad University of Medical SciencesAzadi SqMashhadIran Pediatrician Hasheminezhad HospitalMashhadIran Department of Pediatrics Faculty of MedicineMashhad University of Medical SciencesMashhadIran

Background The aim of this systematic review is to evaluate the chest computed tomography(CT)findings in infants with confirmed COVID-19 infection by providing a comprehensive review of the existing *** sources A systematic search was conducted on PubMed and Embase from the onset of the COVID-19 outbreak to October 20,2020,for studies that discussed the chest CT findings in infants younger than 1 year with COVID-19 *** A total of 35 studies comprising 70 COVID-19(58.5% boys)confirmed infants were *** mean age of the included patients was 4.1 months with a range of 1 day to 12 *** CT scans showed bilateral abnormalities in 34 patients,and unilateral lung involvement in 25 ***-glass opacities(GGO)(71.43%)were found to be the most prevalent chest CT manifestation,followed by peribronchial thickening(60%),linear or band-shaped opacities(32.8%),consolidation(28.57%),nodule(18.57%),effusion(7.14%)and focal lucency(7.14%).Conclusions GGO and peribronchial thickening were the most prevalent findings in the infants’chest CT *** or band-shaped opacities,consolidation,and pulmonary nodules are more common in infants than in *** findings suggest that the disease is more likely to be presented as an atypical pneumonia(peribronchial thickening and linear or bandshaped opacities)in this age *** chest CT scan manifestations can be classified as typical COVID-19 infection(peripheral GGO),lobar pneumonia(consolidation)and opportunistic infections(pulmonary nodules).

关键词： Computerized tomography COVID-19 Infant SARS-CoV-2 Systematic review

Characteristics of a multi-component MgO-based bioceramic coating synthesized in-situ by plasma electrolytic oxidation

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Journal of Magnesium and Alloys 2021年第5期9卷 1611-1625页

作者： Nasrinsadat Azarian seyed mohammad Mousavi Khoei Department of Mining and Metallurgical Engineering Amirkabir University of Technology(Tehran Polytechnic)P.O.Box 15875-4413TehranIran

Plasma electrolytic oxidation(PEO)has held great potential for the advancement of biodegradable implants,as it helps in developing porous bioceramic coatings on the surface of magnesium *** this research work,MgO-based bioceramic coatings containing the Si,P,Ca,Na,and F elements have been successfully fabricated on an AZ31 magnesium alloy plate utilizing the PEO *** characteristic current-voltage behavior of the samples during the process was surveyed in an electrolyte containing Ca(H_(2)PO_(4))_(2),Na_(2)SiO_(3)·9H_(2)O,Na_(3)PO_(4)·12H_(2)O,NaF,and KOH with a pH of 12.5 and electrical conductivity of 20 mS/cm^(-1).The results revealed that applying a voltage of 350-400 V(that is 50-100 V higher than the breakdown limit)could greatly facilitate the synthesis of a PEO ceramic coating with fewer defects and more uniform *** resulting coating was a compositionally graded bioceramic layer with a thickness in the range of 3.5±0.4 to 6.0±0.7µm,comprising the above-mentioned elements as promising bioactive *** synthesized ceramic features were investigated in terms of the elemental distribution of components through the thickness,which indicated a gradual rise in the Si and P contents and,conversely,a decline in the F content towards the outer *** growth mechanism of the PEO coating has been discussed accordingly.

关键词： Az31 magnesium alloy Plasma electrolytic oxidation Bioceramic Coating MgO-based ceramic

The Hippo Tumor Suppressor Pathway(YAP/TAZ/TEAD/MST/LATS)and EGFR-RAS-RAF-MEK in cancer metastasis

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Genes & Diseases 2021年第1期8卷 48-60页

作者： mohammad reza Zinatizadeh seyed Rouhollah Miri Peyman Kheirandish Zarandi Ghanbar Mahmoodi Chalbatani Catarina Raposo Hamid reza Mirzaei mohammad Esmaeil Akbari Habibollah Mahmoodzadeh Cancer Research Center Shahid Beheshti University of Medical SciencesTehranIran Cancer Research Center Cancer Institute of IranTehran University of Medical ScienceTehranIran Department of Immunology School of MedicineTehran University of Medical SciencesTehranIran Department of Immunology Medical SchoolShahid Beheshti University of Medical SciencesTehranIran Faculty of Pharmaceutical Sciences State University of Campinas-UNICAMP Campinas SPBrazil Cancer Research Center Shohadae Tajrish HospitalDepartment of Radiation OncologyShahid Beheshti University of Medical SciencesTehranIran

Hippo Tumor Suppressor Pathway is the main pathway for cell growth that regulates tissue enlargement and organ size by limiting cell *** pathway is activated in response to cell cycle arrest signals(cell polarity,transduction,and DNA damage)and limited by growth factors or mitogens associated with EGF and *** major pathway consists of the central kinase of Ste20 MAPK(Saccharomyces cerevisiae),Hpo(Drosophila melanogaster)or MST kinases(mammalian)that activates the mammalian AGC kinase dmWts or LATS effector(MST and LATS).YAP in the nucleus work as a cofactor for a wide range of transcription factors involved in proliferation(TEA domain family,TEAD1-4),stem cells(Oct4 mononuclear factor and SMAD-related TGFb effector),differentiation(RUNX1),and Cell cycle/apoptosis control(p53,p63,and p73 family members).This is due to the diverse roles of YAP and may limit tumor progression and *** also coordinates various signal transduction pathways such as Hippo,WNT,TGFb and EGFR,and effects on lack of regulation of TEAD cancerous genes,such as KRAS,BRAF,LKB1,NF2 and MYC,which play essential roles in tumor progression,metastasis,cancer metabolism,immunity,and drug ***,RAS signaling is a pivotal factor in the inactivation of Hippo,which controls EGFR-RAS-RAF-MEK-ERKmediated interaction of Hippo ***,the loss of the Hippo pathway may have significant consequences on the targets of RAS-RAF mutations in cancer.

关键词： Cancer Hippo pathway Metastasis Signaling Tumor suppressor

Reliability modeling of hydraulic system of drum shearer machine

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Journal of Coal Science & Engineering(China) 2011年第4期17卷 450-456页

作者： seyed HADI Hoseinie mohammad Ataie reza Khalookakaei UDAY Kumar Faculty of Mining Petroleum ＆ Geophysics Shahrood University of Technology Shahrood *** Iran Division of Operation and Maintenance Engineering Lulea University of Technology Lulea 97187 Sweden

The hydraulic system plays an important role in supplying power and its transition to other working parts of a coal shearer machine. In this paper, the reliability of the hydraulic system of a drum shearer was analyzed. A case study was done in the Tabas Coal Mine in Iran for failure data collection. The results of the statistical analysis show that the time between failures （TBF） data of this system followed the 3-parameters Weibull distribution. There is about a 54% chance that the hydraulic system of the drum shearer will not fail for the first 50 h of operation. The developed model shows that the reliability of the hydraulic system reduces to a zero value after approximately 1 650 hours of operation. The failure rate of this system decreases when time increases. Therefore, corrective maintenance （run-to-t^ailure） was selected as the best maintenance strategy for it.

关键词： reliability modeling hydraulic system drum shearer maintenance strategy