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Issues in Eulerian-Lagrangian modeling of sediment transport under saltation regime

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International Journal of Sediment Research 2018年第4期33卷 441-461页

作者： Reza Barati Seyed Ali Akbar salehi Neyshabouri Goodarz Ahmadi Faculty of Civil and Environmental Engineering Tarbiat Modares University Water Engineering Research Center Department of Civil Engineering Tarbiat Modares University Department of Mechanical and Aeronautical Engineering Clarkson University

The saltation regime is very important for understanding the sediment transport mechanism. However,there is no consensus on a model for the saltation regime. This study answers several questions raised with respect to the Eulerian-Lagrangian modeling of sediment transport. The first question is why the previous saltation models that use different combinations of hydrodynamic forces yielded acceptable results? The second question is which shear lift model(i.e. a shear lift expression and its coefficient) is more appropriate? Another important question is which hydrodynamic forces have greater contributions to the saltation characteristics of a sediment particle? The last question is what are the contributions of the turbulence fluctuations as well as effects of using two-and three-dimensional(2 D and 3 D) models on the simulation results? In order to fairly answer these questions, a systematic study was done by considering different scenarios. The current study is the first attempt to clearly discuss these issues. A comprehensive 3 D saltation model for non-cohesive sediment was developed that includes all the hydrodynamic forces acting on the particle. The random nature of sediment transport was included using turbulent flow and bed-particle collision models. The eddy interaction model was applied to generate a3 D turbulent flow field. Bed-particle collisions were considered using the concept of a contact zone and a corresponding contact point. The validation of the model was done using the available experimental data for a wide range of sediment size(0.03 to 4.8 cm). For the first question, the results indicated that some of the hydrodynamic effects show opposing trends and some have negligible effects. With these opposing effects it is possible to adjust the coefficients of different models to achieve acceptable agreement with the same experimental data while omitting some aspects of the physics of the process. A suitable model for the shear lift force was develop

关键词： Two-phase model Turbulent flow Sediment transport Saltation Hydrodynamic forces

Effect of post-harvest UV-C irradiation and calcium chloride on enzymatic activity and decay of tomato(Lycopersicon esculentum L.)fruit during storage

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Journal of Integrative Agriculture 2017年第9期16卷 2093-2100页

作者： Saeideh Mansourbahmani Behzad Ghareyazie Sepideh Kalatejari Reza salehi Mohammadi Vahid Zarinnia Department of Horticultural Sciences Science and Research BranchIslamic Azad UniversityTehran ***Iran Agriculture Biotechnology Research Institute of Iran(ABRII)/Agricultural Research Education and Extension Organization(AREEO)Karaj ***Iran Department of Horticultural Sciences University of TehranKaraj ***Iran

Tomato is one of the extensively consumed vegetable crops worldwide. The regular consumption of tomato decreases the incidence of chronic degenerative diseases such as certain types of cancer and cardiovascular diseases. The objective of this study was to find an appropriate method that not only reduces tomatoes decay, but also maintains its post-harvest quality. A factorial experiment based on randomized complete block design with three replications was conducted to evaluate effects of ultraviolet（UV）-C and CaCl_2 applications on tomato during storage. The traits studied included ethylene, polygalacturonase（PG） activity, pectin methyl esterase（PME） activity, firmness, total phenol content, and fungal-induced decay were measured weekly during 35 days of storage. Both UV-C and CaCl_2 treatments had positive effects on tomato quality as compared to control treatment. The 3 and 4.5 k J m^（-2） levels of UV-C and 2% CaCl_2 had positive effects on quality characteristics, respectivly. Fruits treated by UV-C and CaCl_2 had higher phenol and firmness, and less PME activity, PG activity, ethylene production, and decay than the control fruits. In conclusion, increasing in storage duration significantly affected the fruits quality by increasing in ethylene, PME activity, PG activity, decay and decreasing the phenol content and firmness. But UV-C and CaCl_2 led to significant decrease in this adverse impact relative to control treatment.

关键词： CaCl_2 ethylene production firmness PG PME phenol

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A new model for calculating the binding energy of the lithium nucleus under the generalized Yukawa potential and Hellmann potential

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Chinese Physics C 2015年第6期39卷 34-39页

作者： M.Ghazvini N.salehi H.Hassanabadi A.A.Rajabi Department of Physics Shahrood University Department of Basic Sciences Shahrood Branch Islamic Azad University

In this paper, the Schrodinger equation for a 6-body system is studied. We solve this equation for the lithium nucleus by using a supersymmetry method with several specific potentials. These potentials are the Yukawa potential, the generalized Yukawa potential and the Hellmann potential. The results of our model for all calculations show that the ground state binding energy of the lithium nucleus with these potentials is very close to that obtained experimentally.

关键词： lithium calculating nucleus normalized invariance exact fitted dimensions searching applying

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Some Ecological Properties of Pistacia atlantica Desf. in Khojir National Park of Iran

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应用与环境生物学报 2013年第3期19卷 415-420页

作者： Kambiz Taheri Abkenar Ali salehi Jalal Bagheri Hooman Ravanbakhsh Natural Resources Faculty University of Guilan Silviculture and Forest Ecology University of Guilan

Khojir national park is one of the oldest protected areas in Iran that is greatly considerable in terms of biodiversity and ecological ***(Pistacia atlantica Desf.) communities,which create some woodland in this park,are unique because they grow tolerantly in a dry land,in the vicinity of Tehran *** research is about some ecological properties of Pistachio *** dominant community of the area is Pistacia-Amygdalus *** density of Pistacia is 86 per *** density of Pistachio trees was greater in the higher elevation than in the lower *** addition,the collar diameter and the height of trees in the higher class were *** average density of Pistacia in plots in northern slopes was significantly more than southern slopes(at 5% level),but the average collar diameter of them were more on the southern *** distribution,diameter and height of pistachio trees were not significantly related to the percentage of *** the soil variables,the saturated water percentage(SP),N(total nitrogen) and texture of soil were effective factors which played significant role in ordination of plots containing *** the important role of *** forest stands in soil and water conservation in Iran,we should attach more importance to their protection and conservation,as well as activities such as road and dam construction,and garden establishment in such unique ecosystems.

关键词： Pistacia atlantica Khojir National Park site property

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Prevalence of hepatitis C virus infection among hemodialysis patients in the Middle-East: A systematic review and meta-analysis

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World Journal of Gastroenterology 2017年第1期23卷 151-166页

作者： Soheil Ashkani-Esfahani Seyed Moayed Alavian Mohammad salehi-Marzijarani Baqiyatallah Research Center for Gastro-enterology and Liver Diseases Baqiyatallah University of Medical Sciences Student Research Committee Shiraz University of Medical Sciences Department of Biostatistics Shiraz University of Medical Sciences

AIM To determine hepatitis C virus(HCV)infection prevalence in each country of the Middle-East and the overall prevalence of the *** In this systematic review,we gathered all documents related to HCV infection prevalence among hemodialysis patients in 17 middle-east countries from April 2006 to March *** selected only cross-sectional studies that had proper sampling and measurement methods as well as a valid statistical *** After screening of 7311 documents,56 studies were selected reporting the prevalence of HCV infection among hemodialysis patients from 10 countries of the *** countries including United Arab Emirates,Afghanistan,Qatar,Bahrain,Kuwait,Oman,Israel,and Cyprus did not have any relevant document;thus,their latest reports were just *** performed the meta-analysis and determined the prevalence rates for each country as well as the whole *** overall HCV infection prevalence among hemodialysis patients in the region was reported to be 25.3%;Egypt and Syria had the highest reported rates while Iran and Lebanon had the *** investigations are still needed to provide more reliable databases,find main risk factors,and to improve diagnosis and treatment plans,particularly in higher prevalent *** Controlling the prevalence and improving the management methods of HCV infection among hemodialysis patients are of a great concern in the Middle-East region.

关键词： Hepatitis C Hemodialysis Prevalence Middle-East Meta-Analysis Review

Multi-objective energy management of island microgrids with D-FACTS devices considering clean energy, storage systems and electric vehicles

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Clean Energy 2023年第5期7卷 1046-1057页

作者： Mahyar Moradi Mohamad Hoseini Abardeh Mojtaba Vahedi Nasrin salehi Azita Azarfar Department of Electrical Engineering Shahrood BranchIslamic Azad UniversityShahroodIran Department of Basic Sciences Shahrood BranchIslamic Azad UniversityShahroodIran

The development of microgrids is progressing due to intelligent load demands,clean energy,batteries and electric *** presence of such systems in microgrids causes power balance inconsistency,leading to increased power losses and deviation in *** this pa-per,a mixed-integer non-linear programming model is proposed for modelling island microgrid energy management considering smart loads,clean energy resources,electric vehicles and ***,a flexible distributed AC transmission system device is proposed to prevent voltage deviation and reduce power losses.A scenario-based multi-objective function has been proposed to decrease energy losses and voltage deviations and energy outages of clean energy resources,reduce emissions from fossil-fired distributed generation and finally decrease load outages to reduce the vulnerability of the islanded *** the proposed mixed-integer non-linear model and the high number of variables and constraints,a modified evolutionary algorithm based on particle swarm optimization has been proposed to solve the proposed model,which can be more efficient than other algorithms to achieve global optimal *** model presented is implemented on a 33-node island microgrid and the results illustrate that the proposed algorithm and model are effective in reducing energy losses and voltage deviation,as well as reducing the vulnerability of the *** simulation results demonstrate that the proposed approach can lead to significant improvements in the performance of the ***,the ap-proach can result in a 27%reduction in losses,a 6%reduction in pollution and a 31%improvement in ***,the approach allows maximum utilization of renewable energy sources,making it a promising solution for sustainable energy management.

关键词： microgrid D-FACTS clean energy battery electric vehicles evolutionary algorithm

Scour and flow field around a spur dike in a 90° bend

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International Journal of Sediment Research 2008年第1期23卷 56-68页

作者： Majid FAZLI Masoud GHODSIAN Seyed Ali Akbar salehi NEYSHABOURI Department of Civil Engineering Tarbiat Modares University Water Engineering Research Center Department of Civil Engineering Tarbiat Modares University Water Engineering Research Center Department of civil Engineering Tarbiat Modares University

Spur dike is an important element in river training that creates rapid variations in flow field, sediment transport and bed topography. The mechanism of flow and sediment transport in a channel bend is very complex, especially when a spur dike is constructed in a bend. Most of previous investigations on flow behavior and scour around spur dike were carried out in straight channels. In this paper results of experiments on flow field and scour around a spur dike in a 90 degree channel bend are presented. Sand with uniform grain size was used as the bed material. Experiments were conducted for different locations and different lengths of spur dikes at the bend with different values of discharge. The three dimensional flow fields around a spur dike were investigated. The maximum depth of scour was correlated to the Froude numbers, lengths and the locations of spur dike in the bend.

关键词： Spur dike Scouring 90° channel bend Bed topography Movable bed Flow pattern

Modeling the spread of spatio-temporal phenomena through the incorporation of ANFIS and genetically controlled cellular automata: a case study on forest fire

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International Journal of Digital Earth 2013年第1期6卷 51-75页

作者： Mohammad H.Vahidnia Ali A.Alesheikh Saeed Behzadi Sara salehi Geodesy and Geomatics Engineering Department of Geospatial Information SystemK.N.Toosi University of TechnologyTehranIran Faculty of Geodesy and Geomatics Engineering Department of PhotogrammetryK.N.Toosi University of TechnologyTehranIran

Virtual representation and simulation of spatio-temporal phenomena is a promising goal for the production of an advanced digital *** modeling,which is one of the most helpful analyses in the geographic information system(GIS),plays a prominent role in meeting this *** study proposes a new model that considers both aspects of static and dynamic behaviors of spreadable spatio-temporal in cellular automata(CA)***,artificial intelligence tools such as adaptive neuro-fuzzy inference system(ANFIS)and genetic algorithm(GA)were used in accordance with the objectives of knowledge discovery and *** conditions in updating states are considered so traditional CA transition rules can be accompanied with the impact of fuzzy discovered knowledge and the solution of spread *** focused on the estimation of forest fire growth as an important case study for decision makers.A two-dimensional cellular representation of the combustion of heterogeneous fuel types and density on non-flat terrain were successfully linked with dynamic wind and slope *** validation of the simulation on experimental data indicated a relatively realistic head-fire *** investigations showed that the results obtained using the dynamic controlling with GA in the absence of static modeling with ANFIS were unacceptable.

关键词： geographic information system adaptive neuro-fuzzy inference system cellular automata genetic algorithm spatio-temporal spread forest fire digital earth

Co-optimization of integrated energy systems in the presence of renewable energy,electric vehicles,power-to-gas systems and energy storage systems with demand-side management

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Clean Energy 2023年第2期7卷 426-435页

作者： Mahroo Sattar Mahmoud Samiei Moghaddam Azita Azarfar Nasrin salehi Mojtaba Vahedi Department of Electrical Engineering Shahrood BranchIslamic Azad UniversityShahroodIran Department of Electrical Engineering Damghan BranchIslamic Azad UniversityDamghanIran Department of Basic Sciences Shahrood BranchIslamic Azad UniversityShahroodIran

With the widespread penetration of renewable energy sources and energy storage systems,the problem of energy management has received increasing *** of the systems that network owners consider today is the power-to-gas(P2G)*** system causes surplus electricity generated from renewable energy resources or batteries in the network to be converted into gas and sold to the gas *** reasons for the existence of gas distributed generation resources and P2G systems cause the two power and gas networks to *** management and profit making considering these two networks,as a co-optimization of integrated energy systems,is a topic that has been discussed in this study to achieve the best optimal *** the production of renewable energy resources and the purchase price of energy are uncertain,a scenario-based method has been chosen for ***-side management is also one of the important problems in optimal operation of the electricity network,which can have a significant impact on reducing peak load and increasing *** this paper,a mixed-integer quadratic programming model for co-optimization of electric distribution and gas networks in the presence of distributed generation resources,P2G systems,storage facilities,electric vehicles and demand-side management is *** 33-bus distribution network is intended to analyse the proposed *** results of different scenarios show the efficiency of the proposed *** key points are deduced from the obtained results:(i)demand-side management is able to reduce the peak load of the network,(ii)the presence of renewable resources and batteries can cause the network to convert excess electricity into gas and sell it to the gas network in the market and(iii)distributed generation can reduce the purchase of energy from the upstream network and cause a 36% reduction in the cost function.

关键词： optimization linear programming integrated systems power-to-gas scenario-based model electricity distribution