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Communications in Theoretical Physics 2013年第7期60卷 9-18页

作者： H. Hassanabadi S.S. hosseini Z. Molaee Physics Department Shahrood University of Technology Physics Department Semnan University

We study the Klein-Gordon oscillator in commutative, noncommutative space, and phase space with psudoharmonic potential under magnetic field hence the other choice is studying the Klein-Gordon equation oscillator in the absence of magnetic field. In this work, we obtain energy spectrum and wave function in different situations by NU method so we show our results in tables.

关键词： Klein-Gordon oscillator equation noncommutative space noncommutative phase space psudoharmonic potential NU method

New method for estimating flying capacitor voltages in stacked multicell and flying capacitor multicell converters

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第8期11卷 654-662页

作者： Arash KHOSHKBAR SADIGH Gevorg B.GHAREHPETIAN Seyed Hossein hosseini Faculty of Electrical & Computer Engineering University of Tabriz Department of Electrical Engineering Amirkabir University of Technology

Multicell converters are an interesting alternative for medium voltage and high power applications,because of the increased number of output voltage levels and apparent *** two most significant types of multicell converter are the flying capacitor multicell (FCM) converter and its derivative,stacked multicell (SM) *** flying capacitor voltages is an important constraint to the proper performance of FCM and SM ***,observation of the flying capacitor voltages used in active control is valuable,but using voltage sensors for observation increases cost and size of the *** paper deals with a new strategy to estimate the flying capacitor voltages of both FCM and SM *** proposed strategy is based on a discrete time model of the converter and uses only a load current *** circuit was simulated using PSCAD/EMTDC software and simulation results were presented to validate the effectiveness of the proposed estimation strategy in observing the flying capacitor *** is the most significant advantage of the proposed strategy,its performance being based on simple equations.

关键词： Flying capacitor multicell converter Stacked multicell converter Flying capacitor voltage Phase shifted sinusoidal pulse width modulation

Stress-strain behavior of plastic concrete using monotonic triaxial compression tests

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Journal of Central South University 2012年第4期19卷 1125-1131页

作者： Y.Pashang Pisheh S.M.Mir Mohammad hosseini Department of Civil and Environmental Engineering A mirkabir University of TechnologyTehran 15914Iran

The mechanical behavior of plastic concrete used in the cut-off walls of earth dams has been studied. Triaxial compression tests on the specimens in various ages and mix designs under different confining pressures have been done and the stress-strain behavior of such materials and their strength parameter changes have been experimentally investigated. It has been observed that increasing the confining pressures applied on the specimens causes the material behavior to be alike the more ductile materials and the compressive strength increases considerably as well. Moreover, a parametric study has been carded out to investigate the influence of essential parameters on the shear strength parameters of these materials. According to the research, increasing the coarse to fine aggregates ratio leads to the increase of compressive strength of the specimens as well as the increase of the cohesion and internal friction angle of the materials. Furthermore, the bentonite content decrease and the cement factor increase result in an increase of the cohesion parameter of plastic concretes and decrease of the internal friction angle of such materials.

关键词： plastic concrete stress-strain behavior triaxial compression test strength elastic modulus

Effects of geometric design of forest road and roadside vegetation on traffic noise reduction

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Journal of Forestry Research 2016年第2期27卷 463-468页

作者： Seyed Ata Ollah hosseini Seyran Zandi Asghar Fallah Mehran Nasiri Department of Forestry and Forest Economics Faculty of Natural Resources University of Tehran Department of Forestry Faculty of Natural Resources Sari University of Agricultural Sciences and Natural Resources Alborz Road Development and Construction Corporation Civil Engineers office

Geometric design of forest roads and design of their landscapes can reduce noise pollution and its harmful effects on human health. We investigated the effects of technical and biological parameters such as geometric road design and various roadside tree stands on reducing noise pollution according to the tree density and distance from roadway in Darabkola Forests, Sari, Iran. We recorded the noise generated by a car （Land Rover） relative to changes in longitudinal slope, horizontal curve radius and type of road pavement. We also measured noise levels according to roadside tree density and stand type （coniferous and hardwood） in 40 rectangular plots of three widths （25, 100 and 300 m） and 50 m length that were randomly demar- cated along forest roads. The changes in noise level were recorded using a decibel meter with an accuracy of q-1.5 dB and resolution of 0.1 dB. Noise levels were higher alongside unpaved roads than alongside paved roads. There was an inverse relationship between the measured noise level and horizontal curve radius. The rate of noise level on horizontal curve with a radius less than 30, 30-45 m and more than 45 m were 64.8, 70.8 and 75.9 dB, respectively. The noise level increased with the increasing longitudinal slope of the road. There was a significant difference between the noise level on slopes less than 3 % （67 dB） and 3-8 % （71.2 dB） in comparison with slopes greater than 8 % （77.8 dB）, （p 〈 0.05）. Pinus brutia L. reduced the noise level more （about 6 dB） in stands of 1/3 density of mixed hardwoods within 25 m from middle of the road. Careful design of geometric properties of forest roads as well as planting coniferous trees with hardwoods is a suitable solution for reducing noise pollution.

关键词： Forest road Noise pollution Noise level Vegetation Distribution

Minimally invasive and open gallbladder cancer resections: 30-vs 90-day mortality

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Hepatobiliary & Pancreatic Diseases International 2017年第4期16卷 405-411页

作者： Naeem Goussous Motahar hosseini Anne M Sill Steven C Cunningham Department of Surgery Saint Agnes HospitalBaltimoreMDUSA

BACKGROUND:Minimally invasive surgery is increasingly used for gallbladder cancer *** mortality at 30 days is low,but 90-day mortality is ***:Using National Cancer Database(1998-2012),all resection patients were ***-and 90-day mortality rates were ***:A total of 36 067 patients were identified,19 139(53%) of whom underwent *** age was 71 years and 70.7% were ***-day mortality following surgical resection was 2.3-fold higher than 30-mortality(17.1% vs 7.4%).There was a statistically significant increase in 30-and 90-day mortality with poorly differentiated tumors,presence of lymphovascular invasion,tumor stage,incomplete surgical resection and low-volume centers(P<0.001 for all).Even for the 1885 patients who underwent minimally invasive resection between 2010 and 2012,the 90-day mortality was 2.8-fold higher than the 30-day mortality(12.0% vs 4.3%).CONCLUSIONS:Ninety-day mortality following gallbladder cancer resection is significantly higher than 30-day *** mortality is associated with tumor grade,lymphovascular invasion,tumor stage,type and completeness of surgical resection as well as type and volume of facility.

关键词： gallbladder cancer laparoscopic minimally invasive survival radical cholecystectomy complications

Dirac oscillator in noncommutative space

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Chinese Physics C 2014年第6期38卷 23-29页

作者： H.Hassanabadi S.S.hosseini S.Zarrinkamar Physics Department Shahrood University Shahrood Iran P. O. Box: ***-316 Shahrood Iran Department of Basic Sciences Garmsar Branch Islamic Azad University Garmsar Iran

We study the Dirac oscillator problem in the presence of the Aharonov-Bohm effect with the harmonic potential in commutative and noncommutative spaces in S-= V and S =-V symmetry limits. We calculate exact energy levels and the corresponding eigenfunctions by the Nikiforov-Uvarov （NU） method and report the impact of the spin and the magnetic flux on the problem. Helpful numerical data is included.

关键词： Dirac oscillator Aharonov-Bohm effect harmonic potential noncommutative space Nikiforov-Uvarov(NU) method

Prediction of the Behavior of a Power System Using Root Cause Failure Analysis

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Fluid Dynamics & Materials Processing 2022年第3期18卷 815-833页

作者： Seyed Mohammad Seyed hosseini Kamran Shahanaghi Safar Shasfand Iran University of Science and Technology Tehran***Iran

The thermo-economic performance of a gas turbine is simulated using a fish bone technique to characterize the major equipment failure *** a fault tree analysis and a Pareto technique are implemented to identify the related failure modes,and the percentage and frequency of failures,respectively.A pump 101 and drier 301 belonging to the Tabriz Petrochemical Company are considered for such analysis,which is complemented with a regression method to determine a behavioral model of this equipment over a twenty-year *** findings indicate that 81%of major failure factors in production equipment are related to the executive procedures(24%),human error(22%),poor quality of materials and parts(20%),and lack of personnel training(15%).

关键词： Combined heat and power root analysis thermoeconomic performance fault tree Pareto behavioral model

Fabrication of SrFe_(12-x)Ni_xO_(19) nanoparticles and investigation on their structural, magnetic and dielectric properties

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International Journal of Minerals,Metallurgy and Materials 2015年第8期22卷 876-883页

作者： S.E.Mousavi Ghahfarokhi S.hosseini M.Zargar Shoushtari Department of physics Shahid Chamran University of Ahvaz

Sr Fe12-xNixO19 nanoparticles(x = 0–1) were synthesized by a combustion sol–gel method. Their structure, dielectric and magnetic properties were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM), an LCR metry, and vibrating sample magnetometry(VSM).The results reveal that all samples of Ni doped compounds(Sr Fe12-xNixO19) with x < 0.2 are single phase. It appears that the Fe3+ ions are substituted by Ni2+ ions on the crystallographic sites of the Sr Fe12O19 structure; however, for x ≥ 0.2, the secondary Ni phase ferrite(Ni Fe2O3) appears, which reduces the saturation magnetization and coercivity. In addition, Ni doping reduces the dielectric constant, dielectric loss, and alternating current(ac) electrical conductivity of the samples. The variation in ac conductivity(σac) with frequency shows that the electrical conductivity in these ferrites is mainly attributed to the electron hopping ***; all the single-phase Ni doped samples are suitable for use in magnetic recording media and microwave devices.

关键词： magnetic particles nanoparticles structure dielect

Comprehensive power swing detection by current signal modeling and prediction using the GMDH method

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Protection and Control of Modern Power Systems 2021年第1期6卷 204-214页

作者： Seyed Amir hosseini Behrooz Taheri Hossein Askarian Abyaneh Farzad Razavi Department of Electrical Engineering Golpayegan University of TechnologyIsfahanIran Faculty of Electrical Biomedical and Mechatronics EngineeringQazvin BranchIslamic Azad UniversityQazvinIran Department of Electrical Engineering Amirkabir University of TechnologyTehranIran

Power swing is an undesirable variation in power flow. This can be caused by large disturbances in demand load, switching, disconnection or reclosing lines. This phenomenon may enter the zones of distance relays and cause relay malfunction leading to the disconnection of healthy lines and undermining network reliability. Accordingly, this paper presents a new power swing detection method based on the prediction of current signal with a GMDH (Group Method of Data Handling) artificial neural network. The main advantage of the proposed method over its counterparts is the immunity to noise effect in signals. In addition, the proposed method can detect stable, unstable, and multi-mode power swings and is capable of distinguishing them from the variety of permanent faults occurring simultaneously. The method is tested for different types of power swings and simultaneous faults using DIgSILENT and MATLAB, and compared with some latest power swing detection methods. The results demonstrate the superiority of the proposed method in terms of response time, the ability to detect power swings of different varieties, and the ability to detect different faults that may occur simultaneously with power swings.

关键词： Power swing Distance relay Power system protection GMDH

Survey of tick species parasiting domestic ruminants in Ghaemshahr county,Mazandaran province,Iran

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Asian Pacific Journal of Tropical Medicine 2010年第10期3卷 804-806页

作者： hosseini Vasoukolaei Nasibeh Telmadarraiy Zakkyeh Vatandoost Hassan Yaghoobi Ershadi Mohammad Reza.hosseini Vasoukolaei Morteza Oshaghi Mohammad Ali Department of Medical Entomology and Vector Control School of Public HealthTehran University of Medical Sciences Department of Biotechnology Faculty of AgricultureBu-Ali Sina University

Objective:To determine the tick species parasitizing domestic ruminants in Ghaemshahr county in Mazandaran,a Caspian province in the north of ***:About 361 sheep, 54 goats and 10 cattle of 18 herds in several villages in Ghaemshahr were inspected for tick *** ticks were preserved in 70% alcohol and ***:About 323 ticks(207 female,116 male) were collected,the occurrence of ticks on sheep,goats and cattle were 28.3% .22.2% and 20.0% *** mean number of ticks on each animal was low (3-5 ticks per animal).Rhipicephalus sanguineus,Rhipicephalus *** ricinus,Boophilus annulalus,Haemaphysalis punctata and Haemaphysalis numidiana were the tick species we *** sanguineus were the most abundant species in the study *** largest number of ticks were generally present from April to July,mostly in animal ears and tails. Ixodes,Boophilus and Haemaphysalis occurred in mountainous areas of *** Rhipicephalus were present in both mountains and plains of the study ***:The result of this study is a survey of tick species from domestic animals in Iran and implication of possible prevention measures for diseases transmitted by ticks.

关键词： Ticks Domestic ruminants Ghaemshahr Iran