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Dynamic Modeling and Closed-loop Control of hybrid Grid-connected Renewable Energy System with Multi-input Multi-output Controller

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Journal of Modern Power Systems and Clean Energy 2021年第1期9卷 94-103页

作者： Mahdi Salimi Fereshteh Radmand Mansour hosseini Firouz the Department of Electrical Engineering Ardabil BranchIslamic Azad UniversityArdabilIran

In this study, a novel approach for dynamic modeling and closed-loop control of hybrid grid-connected renewable energy system with multi-input multi-output(MIMO) controller is proposed. The studied converter includes two parallel DC-DC boost converters, which are connected into the power grid through a single-phase h-bridge inverter. The proposed MIMO controller is developed for maximum power point tracking of photovoltaic(PV)/fuel-cell(FC) input power sources and output power control of the grid-connected DC-AC inverter. Considering circuit topology of the system, a unique MIMO model is proposed for the analysis of the entire system. A unique model of the system includes all of the circuit state variables in DCDC and DC-AC converters. In fact, from the viewpoint of closed-loop controller design, the hybrid grid-connected energy system is an MIMO system. The control inputs of the system are duty cycles of the DC-DC boost converters and the amplitude modulation index of DC-AC inverters. Furthermore, the control outputs are the output power of the PV/FC input power sources as well as AC power injected into the power grid. After the development of the unique model for the entire system, a decoupling network is introduced for system input-output linearization due to inherent connection of the control outputs with all of the system inputs. Considering the decoupled model and small signal linearization, the required linear controllers are designed to adjust the outputs. Finally, to evaluate the accuracy and effectiveness of the designed controllers, the PV/FC based grid-connected system is simulated using the MATLAB/Simulink toolbox.

关键词： Multi-input multi-output(MIMO)converter maximum power point tracking grid-connected inverter conversion function matrix

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New proposed method for prediction of reservoir sedimentation distribution

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International Journal of Sediment Research 2015年第3期30卷 235-240页

作者： h.hosseinjanzadeh K.hosseini K.Kaveh S.F.Mousavi Faculty of Civil Engineering Semnan University

Prediction of sediment distribution in reservoirs is an important issue for dam designers to determine the reservoir active storage *** proposed to calculate sediment distribution are varied,and mainly *** all the methods currently available,only area-reduction and areaincrement methods are considered as the principal methods for prediction of sediment *** this paper,data of 16 reservoirs in the United States are used to propose a new empirical method for prediction of sediment distribution in *** the proposed method,reservoir sediment distribution is related to sediment volume and original reservoir *** validate the accuracy of the new proposed method,obtained results are compared with survey data for two *** results of this investigation showed that the proposed method has an acceptable accuracy.

关键词： Reservoir classification Reservoir coefficient Depth-capacity equation

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焊接参数对半固态搅拌焊接Mg-9Al-1Zn镁合金的影响

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Transactions of Nonferrous Metals Society of China 2016年第10期26卷 2586-2594页

作者： V.A.hosseini h.AAShURI A.h.KOKABI Department of Engineering Science University West Materials Science and Engineering Department Sharif University of Technology

研究焊接温度和转速对半固态搅拌焊接AZ91合金的影响。将Mg-25%Zn中间层夹在两块AZ91板材中间,然后将基体金属和中间层加热至半固态状态。在不同温度和转速下用钻头对焊缝进行搅拌。利用光学显微镜和扫描电子显微镜研究材料的显微组织... 详细信息

研究焊接温度和转速对半固态搅拌焊接AZ91合金的影响。将Mg-25%Zn中间层夹在两块AZ91板材中间,然后将基体金属和中间层加热至半固态状态。在不同温度和转速下用钻头对焊缝进行搅拌。利用光学显微镜和扫描电子显微镜研究材料的显微组织、空洞形成和偏析。采用硬度分布图和冲剪实验对接头的焊接质量和均匀性进行排序。结果表明,当焊接温度为530°C,转速为1600 r/min时,可得到最低的空洞含量(2.1%)和最高的抗剪强度(188 MPa)。温度和转速过高或太低都使焊接质量和抗剪强度降低。因此,在中等温度和转速下,半固态搅拌焊接可以获得均匀的接头和与基体相近的力学性能。

关键词： Mg-Al-Zn合金机械搅拌半固态搅拌焊接

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工艺参数对摩擦辅助管应变法加工管组织和力学性能的影响

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Journal of Central South University 2021年第10期28卷 3008-3017页

作者： S.h.hosseini M.SEDIGhI School of Mechanical Engineering Iran University of Science and TechnologyTehran 16846-13114Iran

研究了摩擦辅助管应变(FATS)法对管材组织和力学性能的影响。采用有限元法分析并进行实验测试。用Taguchi设计(ATD)进行分析,改变转速、进给速率和模具角度来进行数值和实验试验。结果表明,提高进给速率和降低转速提高了Zener-hollomon... 详细信息

研究了摩擦辅助管应变(FATS)法对管材组织和力学性能的影响。采用有限元法分析并进行实验测试。用Taguchi设计(ATD)进行分析,改变转速、进给速率和模具角度来进行数值和实验试验。结果表明,提高进给速率和降低转速提高了Zener-hollomon参数(Z),减小了平均晶粒尺寸,而对模具角度没有显著影响。增加Z值可以减小晶粒尺寸,增强加工样品的流动应力。实验结果表明,具有最大Z值的样品其晶粒尺寸从初始的40μm细化到8μm,其流动应力增加5倍。

关键词：摩擦辅助管应变工艺参数微观结构 Taguchi法有限元模拟

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采用上限方法确定反挤压加工功和最优坯料半径（英文）

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Transactions of Nonferrous Metals Society of China 2016年第8期26卷 2170-2178页

作者： S.h.hosseini K.ABRINIA School of Mechanical Engineering College of Engineering University of Tehran

采用上限方法开发了一种新的改进反挤压方法。在这个方法中,将变形区划分为4个不同的区域,然后对每个区的运动许可速度场进行了设定。对变形区的总耗散功和挤压功进行了计算。对一些重要的几何参数与挤压力和耗散功的关系进行了探讨。... 详细信息

采用上限方法开发了一种新的改进反挤压方法。在这个方法中,将变形区划分为4个不同的区域,然后对每个区的运动许可速度场进行了设定。对变形区的总耗散功和挤压功进行了计算。对一些重要的几何参数与挤压力和耗散功的关系进行了探讨。考虑到最小的相对挤压压力,通过上限方法获得了最优的坯料半径。同时,采用有限元法对问题进行了分析并与采用上限方法获得的结果进行了比较。最后,将上限方法和有限元方法的计算结果与工业纯铝的实验结果进行了比较,结果表明他们之间吻合较好。

关键词：改进反挤压上限方法有限元分析最优坯料半径

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Antimicrobial susceptibility of helicobacter pylori strains isolated from patients in Shiraz, Southern Iran

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World Journal of Gastroenterology 2010年第45期16卷 5746-5751页

作者： Shohreh Farshad Abdolvahab Alborzi Aziz Japoni Reza Ranjbar Kazem hosseini Asl Parisa Badiee Maneli Amin Shahidi Marziyeh.hosseini Professor Alborzi Clinical Microbiology Research Centre Shiraz University of Medical SciencesShiraz 71937-11351Iran Molecular Biology Research Center Baqiyatallah University of Medical SciencesTehran 19945-581Iran Gastroenterohepatology Research Center Shiraz University of Medical SciencesNemazee HospitalShiraz 71345-1414Iran

AIM: To improve our understanding of Iranian regional variation in helicobacter pylori (h. pylori ) antibiotic resistance rates to find the best antibiotic therapy for eradication of h. pylori ***: A total of 266 patients undergoing endoscopy in Shiraz, Southern Iran, were included in this study. h. pylori strains were isolated from antral biopsies by culture and confirmed by the rapid urease-test and gram staining. Antibiotic susceptibility of h. pylori isolates was determined by ***: A total of 121 h. pylori strains were isolated, 50 from male and 71 from female patients. Data showed that 44% (n = 53), 20% (n = 24), 5% (n = 6), and 3% (n = 4) of all strains were resistant to the antibiotics metronidazole, amoxicillin, clarithromycin, and tetracycline, respectively. When the antibiotics were considered together we found 11 sensitivity patterns for the strains. Resistance to metronidazole was significantly higher in female than in male patients (P he metronidazole-resistant isolates, the minimum inhibitory concentrations (MICs) exceeded 256 μg/***: We found a moderate rate of primary resistance to metronidazole. however, a high MIC (> 256 mg/L) which was found in 71% of the isolates is considerable. In the case of amoxicillin, an increased resistance rate of 20% is worrying. Resistance to clarithromycin and tetracycline is also emerging among the h. pylori strains in our region.

关键词： Gastric disorders helicobacter pylori Iran Sensitivity Treatment

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Inducible nitric oxide synthetase genotype and helicobacter pylori infection affect gastric cancer risk

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World Journal of Gastroenterology 2012年第35期18卷 4917-4924页

作者： Alireza Rafiei Vahid hosseini Ghasem Janbabai Bahman Fazli Abulghasem Ajami Zahra hosseini-khah Jeremy J Gilbreath D Scott Merrell Faculty of Medicine Molecular and Cell Biology Research CenterMazandaran University of Medical Sciences Department of Internal Medicine Mazandaran University of Medical Sciences Department of Internal Medicine Imam HospitalMazandaran University of Medical Sciences Department of Microbiology and Immunology Uniformed Services University of the Health Sciences

AIM:To investigate the association of the inducible nitric oxide synthetase(iNOS) C150T polymorphism with helicobacter pylori(***) infection and gastric cancer(GC) risk in ***:In order to determine whether there was a correlation between iNOS genotype and GC in Iran,we conducted a case-control study using samples from 329 *** each sample,the C150T iNOS polymorphism was genotyped by polymerase chain reaction(PCR) and restriction *** were grouped by cancer presence,demographic and behavior characteristics,and *** infection *** tests were conducted to determine whether any behavioral factors or a particular iNOS genotype was associated with GC in the study ***:In this population,we found that smoking,hot beverage consumption,a familial history of GC and *** infection status were significantly associated with GC development(P = 0.015,P he distribution of the C150T iNOS genotypes among the two study groups was not statistically significant alone,but was impacted by *** infection *** compared to the *** infected group,cancer patients who had a heterozygous CT genotype and were also infected with *** were 2.1 times more at risk of developing GC [odds ratio(OR) = 2.1,P = 0.03] while those with a homozygous TT genotype and infected with *** were 5.0 times more at risk of developing GC(OR = 5.0,P = 0.029).In contrast,this association was not seen in patients in the control ***:A CT or TT polymorphism at position 150 in the iNOS gene significantly increases the risk of GC and may be a marker for GC susceptibility.

关键词：一氧化氮合成酶感染状况癌症患者幽门螺杆菌基因型诱导型风险幽门螺旋杆菌

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Effects of Pits and Mounds Following Windthrow Events on Soil Features and Greenhouse Gas Fluxes in a Temperate Forest

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Pedosphere 2015年第6期25卷 853-867页

作者： Yahya KOOCh Sakineh Mollaei DARABI Seyed Mohsen hosseini Department of Forestry Faculty of Natural Resources & Marine SciencesTarbiat Modares University

Pit and mound micro-relief(resultant microsites from trees uprooted by windthrow) could have regimes of microclimate and soil features that differ from areas of undisturbed soil. In an attempt to provide a comprehensive evaluation of the significance of pits and mounds on soil features and also the dynamics of greenhouse gas(GhG) fluxes at local scale, this study was carried out in a reserved area of Darabkola forest in Mazandaran Province, northern Iran. The age of a pit and mound was considered equal to the degree of decay of the blown down tree. Three microsites were distinguished, consisting of pit bottom(PB), mound top(MT) and undisturbed area(UA). Soil samples were taken at 0–15 and 15–30 cm depths from all microsites and analysed for soil physical, chemical and biological features. Our findings suggested that in context of forest ecology, pits and mounds following windthrow events should be considered as an effective factor influencing soil features(i.e., density, texture, water content, p h, organic C, total N, available nutrients and earthworm density/biomass) and especially GhG fluxes. Results showed that MT acted as a sink for N2O(-0.010 mg N2 O m-2d-1) and Ch4(-0.257 mg Ch4m-2d-1) fluxes and also produced lower CO2 concentrations(0.095 mg CO2 m-2d-1) than PB(0.207 mg CO2 m-2d-1) and UA(0.098 mg CO2 m-2d-1). As a consequence, a separation into pits/mounds would be important for a precise budgeting of greenhouse gases.

关键词：温室气体森林土壤土壤特征通量事件风倒 CO2浓度温带

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静电强化乳液中油滴(纳米尺度)聚并过程(英文)

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Chinese Journal of Chemical Engineering 2012年第4期20卷 654-658页

作者： hosseini M. ShAhAVI M.h. Faculty of Chemical Engineering Babol Noshirvani University of TechnologyBabolIran

Oil droplets in nanometer scale which are dispersed in water cannot be separated *** attractive technique is carried out by electrical phenomena to demulsify oil in water *** this research,non-uniform electric field or dielectrophoresis(DEP) is applied to remove sunflower oil(which is dispersed in the water).Effects of temperature,time and voltage(using AC-electric field) were considered to get the highest DEP-force(Fdi) and the best *** oil particles sizes with average of approximately 76 nm have been shown using a ZetaSizer Nano ZS,Model ZEN 1600(Malvern Instrument Ltd.).The maximum separation efficiency of 85% is obtained at the optimum temperature of 38 ℃ and voltage of 3000 V.

关键词：纳米级水乳剂静电增强油滴聚结最佳温度水包油乳液非均匀电场

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Investigation of salinity impacts on germination and growth of two forest tree species at seedling stage

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Journal of Forestry Research 2013年第4期24卷 703-708页

作者： Seyed Mohammad hosseini Nasr Sekineh Kiani Savadkoohi Elahe Ahmadi Department of Forestry Sari Agricultural Sciences and Natural Resources University

Soil salinity is becoming an increasingly serious constraint to plant growth in many parts of the world; this is particularly common in semi-arid and arid zones. This study was conducted to evaluate the effect of different concentrations of salt on seed germination and seedling growth of Acacia albida and A. salicina. Collected seeds were treated with h2SO4 98% for 35 min then left to germinate in a controlled growth chamber. Seeds were grown at salinity levels of 0.1, 0.2 and 0.3 mol.L1 of Nah2PO4.h20. Germination parameters and seedling growth indices were measured after 35 days. The mean of total length ofA. salicina in all salinity concentrations was more than that of ：4. albida. The fresh weight of stem and root of ：4, albida was more than that of ：4. salicina. Growth of control seedlings was higher than for other treatments and the fresh weight of stems of two species at salt concentrations of 0.2 and 0,3 *** decreased with increasing concentration of salt. Most Control seeds germinated at salinity of 0.1 *** and germination index, final germination and seeds stamina was greater at low levels of salinity.

关键词： soil salinity germination salt concentration Acacia albida,Acacia salicina.

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