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Journal of Environmental Sciences 2009年第10期21卷 1438-1445页

作者： masoud Tabari Azadeh Salehi Department of Forestry Faculty of Natural Resources and Marine Sciences Tarbiat Modares University

The effects of municipal sewage irrigation on the soil and black locust （Robinia pseudoacacia L.） tree were studied. For this purpose, two artificial black locust stands under irrigation of municipal sewage and well water were selected in south of Tehran, Iran. Data were collected using technique of systematic random sampling with 4 replicates in each stand. It was found that the growth of black locust tree, as indicated by diameter at breast height, total height, crown length, average crown diameter, basal area and volume, in sewage irrigation stand was much higher than that of well water irrigation stand （P 〈 0.01）. Plant analysis indicated that concentrations of leaf nutrients （N, E K, Ca, Mg, Na, Fe, Mn, Cu and Zn） were greater in sewage-irrigated trees, without toxicity to the minerals of tree leaf, than those of well waterirrigated trees, and positively correlated with their respective value in soil. Ni, Cr and Pb were not detected in leaf samples. Application of sewage resulted in a 1.5-fold increase in the concentrations of soil nutrients, Ni, Cr and Pb. Among these minerals only Pb and Ni in some soil samples exceeded the toxicity limit. The increase in pH, electrical conductivity （EC） and organic carbon of soil was also observed in sewage irrigation. Results confirm that besides the use as irrigation water, municipal sewages are also a potential source of plant nutrients. However, significant accumulation of heavy metals such as Pb and Ni in soil needs to be monitored.

关键词： afforestation irrigation municipal sewage black locust nutrient heavy metal

Developing Bi-CG and Bi-CR Methods to Solve Generalized Sylvester-transpose Matrix Equations

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International Journal of Automation and computing 2014年第1期11卷 25-29页

作者： masoud Hajarian Department of Mathematics Faculty of Mathematical SciencesShahid Beheshti UniversityGeneral Campus

The bi-conjugate gradients(Bi-CG)and bi-conjugate residual(Bi-CR)methods are powerful tools for solving nonsymmetric linear systems Ax=*** using Kronecker product and vectorization operator,this paper develops the Bi-CG and Bi-CR methods for the solution of the generalized Sylvester-transpose matrix equationp i=1(Ai X Bi+Ci XTDi)=E(including Lyapunov,Sylvester and Sylvester-transpose matrix equations as special cases).Numerical results validate that the proposed algorithms are much more efcient than some existing algorithms.

关键词： Linear systems iterative method bi-conjugate gradients(Bi-CG) method bi-conjugate residual(Bi-CR) method Sylvester matrix equation

FORECASTING EXCHANGE RATES: AN OPTIMAL APPROACH

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Journal of Systems Science & Complexity 2014年第1期27卷 21-28页

作者： BENEKI Christina YARMOHAMMADI masoud School of Business and Economics Department of Business Administration Technological Educational Instituteof Ionian Islands 31100 Lefkada Greece. Department of Statistics Payame Noor University 19395-4697 Tehran Islamic Republic of Iran.

This paper looks at forecasting daily exchange rates for the United Kingdom, European Union, and China. Here, the authors evaluate the forecasting performance of neural networks （NN）, vector singular spectrum analysis （VSSA）, and recurrent singular spectrum analysis （RSSA） for fore casting exchange rates in these countries. The authors find statistically significant evidence based on the RMSE, that both VSSA and RSSA models outperform NN at forecasting the highly unpredictable exchange rates for China. However, the authors find no evidence to suggest any difference between the forecasting accuracy of the three models for UK and EU exchange rates.

关键词： China European union exchange rates forecasting neural networks recurrent singularspectrum analysis United Kingdom vector singular spectrum analysis.

EXCHANGE RATE FORECASTING WITH OPTIMUM SINGULAR SPECTRUM ANALYSIS

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Journal of Systems Science & Complexity 2014年第1期27卷 47-55页

作者： GHODSI Mansi YARMOHAMMADI masoud Executive Business Center Bourremouth University 89 Holdenhurst Road BH8 8EB UK Institute for In-ternational Energy Studies Tehran Iran. Department of Statistics Payame Noor University 19395-3697 Tehran I. R. Iran.

Forecasting exchange rate is undoubtedly an attractive and challenging issue that has been of interest in different domains for many years. The singular spectrum analysis （SSA） technique has been used as a promising technique for time series forecasting including exchange rate series. The SSA technique is based upon two main choices： Window length, L, and the number of singular values, r. These values are very important for the reconstruction stage and forecasting purposes. Here the authors consider an optimum version of the SSA technique for forecasting exchange rates. The forecasting performances of the SSA technique for one-step-ahead forecast of six exchange rate series are used to find the best L and r.

关键词： Exchange rate forecasting optimal singular spectrum analysis singular value windowlength.

H pylori seroprevalence in patients with lung cancer

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World Journal of Gastroenterology 2007年第16期13卷 2349-2351页

作者： Katayoon Najafizadeh Sayeed Falah Tafti masoud Shiehmorteza masoud Saloor masoud Jamali Department of Respiratory Medicine National Research Institute of Tuberculosis and Lung Diseases Tehran 19556 Iran

AIM: To assess H pylori seroprevalence in lung cancer and determine whether there is a potential association between lung cancer and H pylori infection. METHODS: The study was conducted on forty consecutive patients with lung cancer, confirmed by pathology (32 men, 8 women; mean age 55.50 ± 11.91 years, range 16-77 years). Forty healthy subjects (25 men, 15 women; mean age 43.08 ± 12.60 years, range 20-79 years) from the patients’ family members were matched to each case subject on the basis of age and socioeconomic status. H pylori infection was detected with a commercially available immunoglobulin G (IgG) enzyme-linked immunosorbent assay (Trinity kit, Biotech co., USA), previously validated in adults (86% sensitivity, 96% specificity) against a gold standard of culture and histology. RESULTS: H pylori seropositivity was present in 52.5% of patients with lung cancer in comparison to 45.0% of healthy control subjects. Although H pylori seropositivity was more frequent in lung cancer patients than in controls, the difference did not reach statistical significance (OR = 1.35, 95% CI = 0.56-3.25; P = 0.65). In addition, there was no significant difference between cases and controls in terms of gastrointestinal symptoms. CONCLUSION: The earlier described association between H pylori infection and lung cancer was not supported in this study. Further studies with larger sample sizes should be undertaken to assess the frequency of H pylori infection in patients with lung cancer and their potential association.

关键词： Lung neoplasm H pylori Helicobacter infections/complications Carcinoma/Non-small cell Carcinoma/Squamous cell Case-control studies

利用标准化降雨指数对伊朗法尔斯省干旱危害的GIS分析（英文）

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Journal of Resources and Ecology 2024年第2期 439-447页

作者： masoudI masoud TAHERI Zahra 伊朗设拉子大学农业学院自然资源与环境工程系伊朗德黑兰大学自然资源学院环境科学系

干旱是广泛影响经济和环境的主要自然灾害之一。因此，有必要采用诸如标准化降雨指数（SPI）等指标来研究干旱的影响，以辨析决策和规划的现实条件。本研究的目的是利用SPI指数分析伊朗南部法尔斯省的干旱空间格局。本文根据法尔斯省42... 详细信息

干旱是广泛影响经济和环境的主要自然灾害之一。因此，有必要采用诸如标准化降雨指数（SPI）等指标来研究干旱的影响，以辨析决策和规划的现实条件。本研究的目的是利用SPI指数分析伊朗南部法尔斯省的干旱空间格局。本文根据法尔斯省42个站点的数据，对1990–2019年间的干旱灾害格局进行了评价。评价模型中使用的干旱危害标准包括：该时期的最严重干旱程度、干旱趋势和连续干旱年的最大数量，最终的干旱灾害图是通过计算干旱强度、连续性和趋势三个指标的算术平均值获得的。三个指标的灾害图和最终灾害脆弱图采用反距离加权法（IDW）插值制图，分为无、轻度、中度、重度和极重度5个危害等级。最终的干旱脆弱性图显示，在研究区南部观察到的中度灾害区域占研究区36%，比在北部和中部观察到的严重和非常严重灾害区（占研究区64%）分布范围更小。

关键词：干旱标准化降雨指数 GIS 灾害地图反距离加权法法尔斯省

Effects of multipass friction stir processing and Mg addition on the microstructure and tensile properties of Al 1050 alloys

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International Journal of Minerals,Metallurgy and Materials 2022年第1期29卷 97-107页

作者： Shahin Arshadi Rastabi masoud Mosallaee Department of Mining and Metallurgy Yazd UniversityYazdIran

The effects of multipass friction stir processing(FSP)and Mg powder addition on the different microstructure parts,including the stir zone(SZ),heat-affected zone(HAZ),and thermomechanically affected zone(TMAZ)of Al 1050 alloy were *** observations revealed that with the increase in the number of FSP passes,the grain size of the SZ decreased in the non-composite and composite samples,whereas that of the TMAZ and HAZ increased in the non-composite ***,the addition of Mg powder resulted in considerable grain refinement,and increasing the number of the FSP passes resulted in a more uniform distribution of Al-Mg intermetallic compounds in the in-situ composite *** of the tensile test showed that the non-composite sample that underwent four passes of FSP exhibited a higher elongation percentage and a ductile fracture in comparison with those of the base metal and the composite ***,this sample exhibited a brittle fracture and a higher tensile strength in comparison with the base metal and the non-composite *** fabrication of composite samples resulted in a remarkable enhancement in hardness in comparison with the base metal and the non-composite samples that underwent FSP.

关键词： friction stir processing Al alloy magnesium tensile properties hardness

Evaluation of ecological capability and land use planning for different uses of land with a new model of EMOLUP in Jahrom County,Iran

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Frontiers of Earth Science 2023年第2期17卷 561-575页

作者： Parviz JOKAR masoud masoudI Department of Natural Resources and Environmental Engineering School of AgricultureShiraz UniversityShiraz ***Iran

Land use planning is one of the basic principles of sustainable development in a region and in a *** main objective of this paper is to test a new model of land use planning in order to evaluate ecological suitability and prioritize different land uses in Jahrom County placed in Fars Province,*** two main steps were prepared for the new model of Eco-Socioeconomic Model of Land Use Planning(EMOLUP).Step 1 includes ecological capability evaluation of different land uses including forest,rangeland,agriculture,conservation,and *** step is composed of the geometric mean method instead of the Boolean method;and step 2 includes land use planning and prioritizing for the various uses mentioned *** step is composed of intersecting ecological capability maps and land use planning,based on two scenarios(economic and social).It was compared with qualitative and current quantitative ***,current land use is employed for calibrating and modifying the *** results of ecological suitability evaluation showed that the EMOLUP model has more accuracy in the process of comparison than other current ***,revised method using the geometric mean(with overall accuracy>72 and kappa index>0.55 for all land uses and rangeland with overall accuracy=32 and kappa index=0.02)is better than Boolean models,and the method of the calibrated geometric mean(with overall accuracy>87 and kappa index>0.73 for all land uses)is the best among different used *** should be noted that the arithmetic mean has the lowest accuracy(with overall accuracy<45 and kappa index<0.24 for all land uses).Also,the results of prioritizing and land use planning showed that the quantitative method with two socio-economic scenarios(result based on average of EPM erosion model=0.3 that means 30%of modification in whole study area land uses)is the best method for land use planning in the study area.

关键词： EMOLUP Model geomean Boolean prioritizing land use capability

Experimental Study of the Unsteady Actuation Effect on Induced Flow Characteristics in DBD Plasma Actuators

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Plasma Science and Technology 2015年第5期17卷 415-424页

作者： Sohrab Gholamhosein POURYOUSSEFI masoud MIRZAEI Department of Aerospace Engineering K N Toosi University of Technology

The main aim of this paper is to investigate unsteady actuation effects on the operation of dielectric barrier discharge （DBD） plasma actuators and to study induced flow characteristics of steady and unsteady actuators in quiescent air. The parameters affecting the operation of unsteady plasma actuators were experimentally measured and compared with the ones for steady actuators. The effects of excitation frequency and duty cycle on the induced flow pattern properties were studied by means of hot-wire anemometers, and the smoke visualization method was also used. It was observed that the current and the mean induced velocity linearly increase with increasing duty cycle while they are not sensitive to excitation frequency. Furthermore, with increasing excitation frequency, the magnitude of vortices shedding from the actuator decreases while their frequency increases. Nevertheless, when the excitation frequency grows beyond a certain level, the induced flow downstream of the actuator behaves as a steady flow. However, the results for steady actuators show that by increasing the applied voltage and carrier frequency, the velocity of the induced flow first increases and then decreases with actuator saturation and the onset of the emission of streaky glow discharge.

关键词： unsteady plasma actuator excitation frequency duty cycle induced flowpattern frequency response sequence

Control strategy of hybrid fuel cell/battery distributed generation system for grid-connected operation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 488-496页

作者： masoud Aliakbar GOLKAR Amin HAJIZADEH Department of Electrical Engineering K.N.Toosi University of TechnologyTehran Iran

This paper presents a control strategy of a hybrid fuel cell/battery distributed generation (HDG) system in distribution systems. The overall structure of the HDG system is given, dynamic models for the solid oxide fuel cell (SOFC) power plant, battery bank and its power electronic interfacing are briefly described, and controller design methodologies for the power conditioning units and fuel cell to control the power flow from the hybrid power plant to the utility grid are presented. To distribute the power between the fuel cell power plant and the battery energy storage, a neuro-fuzzy controller has been developed. Also, for controlling the active and reactive power independently in distribution systems, the current control strategy based on two fuzzy logic controllers has been presented. A Matlab/Simulink simulation model is developed for the HDG system by combining the individual component models and their controllers. Simulation results show the overall system performance including load-following and power management of the HDG system.

关键词： Battery Fuel cell Hybrid distributed generation Intelligent control Power control