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Reduction of the wind erosion potential in dried-up lakebeds using artificial biocrusts

Frontiers of Earth Science 2022年第4期16卷 865-875页

作者： hossein kheirfam Maryam ROOHI Department of Range and Watershed Management Faculty of Natural ResourcesUrmia UniversityUrmia ***Iran Department of Environmental Sciences Urmia Lake Research InstituteUrmia UniversityUrmia ***Iran Microbiology Laboratory Expert Artemia&Aquaculture Research InstituteUrmia UniversityUrmia ***Iran

The artificial creation of biocrusts can be a rapid and pervasive solution to reduce wind erosion potential(WEP)in dried-up lakes(e.g.,Lake Urmia).So,in this study,we created a biocrust by the inoculation of bacteria and cyanobacteria on trays filled by soils collected from the dried-up bed of Lake Urmia,Iran,to reduce WEP in laboratory *** used the wind erodible fraction of soil(EF)and soil crust factor(SCF)equations to calculate the WEP of the treated *** and SCF were decreased(p<0.05)through applying the co-inoculation of bacteria and cyanobacteria by 5.6%and 10.57%,respectively,as compared to the control;also,the"cyanobacteria alone"inoculation decreased EF by 3.9%.Our results showed that the artificial biocrusts created by soil inoculation,especially with the co-using of bacteria and cyanobacteria,significantly reduced the WEP of a newly dried-up ***,we found that inoculation decreased the WEP of the study soil by increasing the soil organic matter content from 3.7 to 5 *** to scanning electron microscopy images,the inoculated microorganisms,especially cyanobacteria,improved soil aggregation by their exopolysaccharides and filaments;thus,they can be used with other factors to estimate the soil erodibility in well-developed *** inoculation technique could be considered as a rapid strategy in stabilizing lakebeds against wind ***,it should be confirmed after additional experiments using wind tunnels under natural conditions.

关键词： biological soil crust dried-up lakes dust storms flowing-sands soil cyanobacteria

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A regional suspended load yield estimation model for ungauged watersheds

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Water Science and Engineering 2018年第4期11卷 328-337页

作者： hossein kheirfam Sahar Mokarram-Kashtiban Department of Environmental Science Urmia Lake Research Institute Urmia University Department of Forestry Tarbiat Modares University

Developing regional models using physiographic, climatic, and hydrologic variables is an approach to estimating suspended load yield(SLY)in ungauged watersheds. However, using all the variables might reduce the applicability of these models. Therefore, data reduction techniques(DRTs), e.g., principal component analysis(PCA), Gamma test(GT), and stepwise regression(SR), have been used to select the most effective variables. The artificial neural network(ANN) and multiple linear regression(MLR) are also common tools for SLY modeling. We conducted this study(1) to obtain the most effective variables influencing SLY through DRTs including PCA, GT, and SR, and then, to use them as input data for ANN and MLR; and(2) to provide the best SLY models. Accordingly, we used 14 physiographic, climatic, and hydrologic parameters from 42 watersheds in the Hyrcanian forest region(in northern Iran). The most effective variables as determined through DRTs as well as the original data sets were used as the input data for ANN and MLR in order to provide an SLY model. The results indicated that the SLY models provided by ANN performed much better than the MLR models, and the GT-ANN model was the best. The determination of coefficient,relative error, root mean square error, and bias were 99.9%, 26%, 323 t/year, and 6 t/year in the calibration period, and 70%, 43%, 456 t/year, and 407 t/year in the validation period, respectively. Overall, selecting the main factors that influence SLY and using artificial intelligence tools can be useful for water resources managers to quickly determine the behavior of SLY in ungauged watersheds.

关键词： Data reduction techniques Forest watershed Sediment yield Regional models Watershed sediment modeling

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Effects of type, level and time of sand and gravel mining on particle size distributions of suspended sediment

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International Soil and Water Conservation Research 2018年第2期6卷 184-193页

作者： Seyed Hamidreza Sadeghi Sudabeh Gharemahmudli hossein kheirfam Abdulvahed Khaledi Darvishan Mahboobeh Kiani Harchegani Pari Saeidi Leila Gholami Mehdi Vafakhah Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor***Mazandaran ProvinceIran Department of Environmental Sciences Urmia Lake Research InstituteUrmia UniversityUrmiaIran Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor46417-76489Iran Department of Range and Watershed Management Sari Agriculture and Natural Resources UniversitySariMazandaran ProvinceIran

Monitoring the sediment transport behavior induced by different interventions, particularly sand mining from rivers, is needed to adaptively manage the watersheds. The particle size distribution of the sus-pended sediment in up and downstream of rivers is one of the main indicators to know about fate of sediments, which may be varied in different conditions. We investigated the effect of some types of sand and gravel (i.e., manual and low, semi-heavy, and heavy machinery) mining on particle size distribution of suspended sediment in the Vaz-e-Owlya, Vaz-e-Sofla and Alesh-Roud riverine mines located in Ma-zandaran Province, northern Iran. The study was conducted on a monthly basis from February, 2012 to January, 2013. Laser granulometry was used to analyze the particle size distribution of suspended se-diment samples taken from up and downstream sections of the study mines. The results revealed that the level and intensity of mining activity affected particle size distribution of suspended sediments. Further statistical assessments in up and downstream sections of the mines proved that sorting, D50, mean, D90, kurtosis, skewness and D10 of the suspended sediment were not significantly influenced by mining activities at levels of 0.09, 0.11, 0.12, 0.15 to 0.69, 0.15–0.69, 0.77, 0.87, 0.97, respectively. While it was not statistically significant, we found that the type of mine and the level of the exploitation changed the particle size distribution of the suspended sediment.

关键词： Mine exploitation Particle size distribution Sediment granulometry Sediment temporal variations

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CSRWA:Covert and Severe Attacks Resistant Watermarking Algorithm

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Computers, Materials & Continua 2025年第1期82卷 1027-1047页

作者： Balsam Dhyia Majeed Amir hossein Taherinia Hadi Sadoghi Yazdi Ahad Harati Faculty of Engineering Ferdowsi University of MashhadMashhad***Iran Department of Computer Techniques Engineering Imam Al-Kadhum CollegeBaghdad10087Iraq

Watermarking is embedding visible or invisible data within media to verify its authenticity or protect *** watermark is embedded in significant spatial or frequency features of the media to make it more resistant to intentional or unintentional *** of these features are important perceptual features according to the human visual system(HVS),which means that the embedded watermark should be imperceptible in these ***,both the designers of watermarking algorithms and potential attackers must consider these perceptual features when carrying out their *** two roles will be considered in this paper when designing a robust watermarking algorithm against the most harmful attacks,like volumetric scaling,histogram equalization,and non-conventional watermarking attacks like the Denoising Convolution Neural Network(DnCNN),which must be considered in watermarking algorithm design due to its rising role in the state-of-the-art *** DnCNN is initialized and trained using watermarked image samples created by our proposed Covert and Severe Attacks Resistant Watermarking Algorithm(CSRWA)to prove its *** this algorithm to satisfy the robustness and imperceptibility tradeoff,implementing the Dither Modulation(DM)algorithm is boosted by utilizing the Just Noticeable Distortion(JND)principle to get an improved performance in this ***,luminance,inter and intra-block contrast are used to adjust the JND values.

关键词： Covert attack digital watermarking DnCNN JND perceptual model robustness

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Discrete time multiple spacecraft formation flying attitude optimal control in presence of relative state constraints

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Chinese Journal of Aeronautics 2021年第4期34卷 293-305页

作者： hossein MORADI PARI hossein BOLANDI Department of Electrical Engineering Iran University of Science and TechnologyTehran 009821Iran

This paper addresses the challenge of synchronized multiple spacecraft attitude reorientation in presence of pointing and boundary constraints with limited inter-spacecraft communication *** attitude pointing constraint among the fleet of spacecraft has also been modeled and considered during the attitude maneuvers toward the desired *** fling control structure that consists of decentralized path planners based on virtual structure approach joint with discrete time optimal local controller is designed to achieve the mission's *** to digital computing of spacecraft's onboard computer,local optimal controller based on discrete time prediction and correction algorithm has been *** time step of local optimal algorithm execution is designed so that the spacecraft track their desired attitudes with appropriate error *** convergence of the proposed architecture and stability of local controller's tracking error within appropriate upper bound are ***,a numerical simulation of a stereo imaging scenario is presented to verify the performance of the proposed architecture and the effectiveness of the algorithm.

关键词： Decentralized Discrete time Formation flying Optimal control Spacecraft Virtual structure approach

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Effect of different treatments on electrokinetic remediation of Zn, Pb and Cd from a contaminated calcareous soil

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Chinese Journal of Chemical Engineering 2021年第10期34卷 255-265页

作者： hossein Beyrami National Salinity Research Center Agricultural ResearchEducation and Extension OrganizationYazdIran

Electrokinetic remediation is a promising method to decontamination of the heavy metals from *** this paper,the remediation of a contaminated calcareous soil with Zn,Cd and Pb sampled from around Zanjan province of Iran,was investigated using electrokinetic *** this paper,the soil contain a high concentration of Zn(1400 mg·kg^(-1)),Cd(15 mg·kg^(-1))and Pb(250 mg·kg^(-1)).Electrokinetic decontamination consists of two series of experiments as follows:(1)the effect of five treatments including the use of distilled water,acetic acid and EDTA electrolyte solutions,and approaching anodes systems,and the circulation flow of electrolyte at two different voltage gradient(i.e.1.33 and 2.66 V·cm^(-1)),and(2)the effect of moisture content(saturated,FC and 0.7 FC,FC indicated soil moisture at "Field Capacity")with a voltage gradient of 1.33 V·cm^(-1).After applying electric current for 5 days,the results of experiments indicated that the removal efficiency of heavy metals can be increased by raising the voltage *** this matter,the highest remediation can be observed among different treatments in EDTA(Ethylene diamine tetra acetic acid)treatment(40.11%,43.10%and 24.7%for Zn,Cd and Pb,respectively).Moreover,the heavy metals removal at the saturated moisture was at the highest level so that 32.62%cadmium,31.33%zinc and 18.82%lead being removed after 120 h of electric current *** decreasing moisture to 0.7 FC,the removal percentage for the three heavy metals obtained 20.97%,18.44%and 12.25%,***,Cd had the highest removal,and Zn and Pb were next among the three heavy metals in question.

关键词： Decontamination Soil moisture Voltage gradient Cadmium Lead Zinc

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Effects of Location,Size and Number of Wind Turbine Receptors on Blade Lightning Protection

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电力系统自动化 2012年第8期36卷 122-127页

作者： hossein Kazemi KAREGAR hossein BAGHERIAN Faculty of Electrical &Computer Engineering Shahid Beheshti University

Electric and magnetic fields generated by lightning cause a serious hazard to various *** wind turbine installations with higher power capacity are *** power capacity requires higher height and so there is more probability of lightning *** are the most probable components to be struck by *** most common lightning protection system for the blades consists of several metallic receptors on the blade *** are connected to the ground by metallic down-conductors placed inside the blade *** paper studies effects of the receptor configurations on protecting the blade against lightning *** this purpose,an analysis procedure based on finite element method(FEM)in COMSOL Multiphysics software environment is *** voltage distribution around the blade is simulated for various configurations of *** best configuration is *** are performed on the blade model of a special wind turbine,which isVESTAS V47".

关键词：风力发电机组受体刀片防雷叶片表面位置最佳配置发电能力

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REMOVAL OF MERCURY FROM WATER USING POLYPYRROLE AND ITS COMPOSITES

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Chinese Journal of Polymer Science 2007年第4期25卷 393-397页

作者： hossein Eisazadeh Faculty of Chemical Engineering University of MazandaranP.O.Box 484BabolIran

One of the suitable methods for removing heavy metals from water is by using surface adsorption process. In this paper, the preparation of polypyrrole and its composites as adsorbents are discussed and the capability of separating mercury from water is investigated. The results indicated that the polypyrrole and its composites are able to remove mercury from aqueous media. Furthermore the adsorption percentage is related to the surface morphology, type of additives and its concentration.

关键词： Polypyrrole and its composites Mercury removal Additives Surface morphology.

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Thermodynamics of 4D dS/AdS Gauss–Bonnet black holes according to consistent gravity theory in the presence of a cloud of strings

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Communications in Theoretical Physics 2022年第4期74卷 72-84页

作者： hossein Ghaffarnejad Faculty of Physics Semnan UniversityP.C.35131-19111SemnanIran

By looking at the Lovelock theorem one can infer that the gravity model given by[1]cannot be applicable for all types of 4D Einstein–Gauss–Bonnet(EGB)curved *** reason for this is that in 4D space-time,the Gauss–Bonnet invariant is a total derivative and hence it does not contribute to gravitational ***,the authors of[2]presented an alternative consistent EGB gravity model instead of[1]by applying a break-of-diffeomorphism *** this work,we use the alternative model to produce a de Sitter(dS)/Anti-de Sitter(AdS)black hole metric and then investigate its thermodynamic behavior in the presence of a cloud of Nambu–Goto *** derivations show that the resulting diagrams of pressure vs specific volume at a constant temperature are similar to that for a van der Waals gas/fluid in an ordinary thermodynamic system in the d S sector but not in the Ad S *** this,we infer that the black hole participates in the small-to-large black hole phase transition in the dS background,while it exhibits a Hawking–Page phase transition in the AdS *** the latter case,an evaporating black hole eventually reaches an AdS vacuum space because of its instability.

关键词： Lovelock gravity string Nambu-Goto Gauss-Bonnet black hole thermodynamic cosmological constant phase transition

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Correlation of the mean activity coefficient of aqueous electrolyte solutions using an equation of state

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Chinese Journal of Chemical Engineering 2016年第10期24卷 1456-1463页

作者： Seyed hossein Mazloumi Chemical Engineering Department Faculty of EngineeringFerdowsi University of Mashhad

Accurate calculation of thermodynamic properties of electrolyte solution is essential in the design and optimization of many processes in chemical industries. A new electrolyte equation of state is developed for aqueous electrolyte solutions. The Carnahan-Starling repulsive model and an attractive term based on square-well potential are adopted to represent the short range interaction of ionic and molecular species in the new electrolyte EOS. The long range interaction of ionic species is expressed by a simplified version of Mean Spherical Approximation theory （MSA）. The new equation of state also contains a Born term for charging free energy of ions. Three adjustable parameters of new eEOS per each electrolyte solution are size parameter, square-well potential depth and square-well potential interaction range. The new eEOS is applied for correlation of mean activity coefficient and prediction of osmotic coefficient of various strong aqueous electrolyte solutions at 25℃ and 0.1 MPa. In addition, the extension of the new eEOS for correlation of mean activity coefficient and solution density of a few aqueous electrolytes at temperature range of 0 to 100℃ is carried out.

关键词： Aqueous electrolyte solution Electrolyte equation of state Activity coefficient Osmotic coefficient Solution density

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