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Assessment of soil erodibility and aggregate stability for different parts of a forest road

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Journal of Forestry Research 2014年第1期25卷 193-200页

作者： Aidin Parsakhoo Majid Lotfalian Ataollah Kavian seyed Ataollah hosseini Department of Forestry Faculty of Forest SciencesGorgan Agricultural Sciences and Natural Resources University Associate Professors Department of ForestryFaculty of Natural ResourcesSari Agricultural Sciences and Natural Resources University Assistant Professor Department of Watershed ManagementFaculty of Natural ResourcesSari Agricultural Sciences and Natural Resources University

We measured erodibility and mean weight diameter （MWD） of soil aggregates in different parts of a forest road. Samples of topsoil were collected from cutslope, fillslope, road surface and forest ground to assess the texture, bulk density, moisture, CaCO3 and organic matter. Soil aggregate stability was determined by wet sieving. Soil erodibility on the road surface was 2.3 and 1.3 times higher than on the fillslope and cutslope, respectively. The forest soil had the lowest erodibility. Aggregate stability of cutslope and road surface were low and very low, respectively. There was a significant negative relationship between cutslope erodibility with CaCO3 and sand content. Cutslope erodibility increased with increasing silt, clay and moisture content. On fillslopes, MWD increased with in-creasing rock fragment cover, plant cover, litter cover, organic matter and sand. There was a strong negative correlation between fillslope erodibility and organic matter, sand and MWD. There was no significant difference between erodibility of bare soil and soils beneathRubus hyrcanusL. and Philonotis marchica （Hedw.） Brid.

关键词： road prism soil erodibility aggregate stability wet sieving Lat Talar forest

Herbaceous species diversity in relation to fire severity in Zagros oak forests,Iran

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Journal of Forestry Research 2014年第1期25卷 113-120页

作者： Morteza Pourreza seyed Mohsen hosseini Ali Akbar Safari Sinegani Mohammad Matinizadeh seyed Jalil Alavai Department of forestry Tarbiat Modares University Soil department Bu-Ali Sina University Research Institute of forest and range lands

Zagros forests are mainly covered byQuercus brantii L. coppices and oak sprout clumps occupy the forest area like patches. We investigated post-fire herbaceous diversity in the first growing season after fire. For this purpose neighboring burned and unburned areas were selected with the same plant species and ecological conditions. The data were collected from areas subjected to different fire severities. Overall 6 treatments were considered with respect to fire severity and the mi-crosites of inside and outside of oak sprout clumps including： unburned inside and outside of sprout clumps （Ni and No）, inside of sprout clumps that burned with high fire severity （H）, inside of sprout clumps that burned with moderate fire severity （M）, outside of sprout clumps that burned with low fire severity （OH and OM）. Different herbaceous com-position was observed in the unburned inside and outside of oak sprout clumps. The species diversity and richness were increased in treatments burned with low and moderate fire severity. However, in treatment burned with high fire severity （H）, herbaceous cover was reduced, even-ness was increased, and richness and diversity were not significantly changed. We concluded that besides the microsites conditions in forest, fire severity is an inseparable part of the ecological effect of fire on her-baceous composition.

关键词： biodiversity fire severity Oak sprout clump Zagros forests,microsite

Robust Authentication and Session Key Agreement Protocol for Satellite Communications

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Computers, Materials & Continua 2022年第6期71卷 5891-5910页

作者： Somayeh Soltani seyed Amin hosseini Seno Juli Rejito Rahmat Budiarto Department of Computer Engineering Ferdowsi University of MashhadMashhad***Iran Faculty of Mathematics and Science Universitas PadjadjaranJatinangor45363Indonesia Faculty of Computer Science Universitas Mercu BuanaJakarta11650Indonesia

Satellite networks are recognized as the most essential communication infrastructures in the world today,which complement land networks and provide valuable services for their *** coverage and service stability of these networks have increased their *** eavesdropping and active intrusion in satellite communications are much easier than in terrestrial networks,securing satellite communications is *** far,several protocols have been proposed for authentication and key exchange of satellite communications,but none of them fullymeet the security *** this paper,we examine one of these protocols and identify its security ***,we propose a robust and secure authentication and session key agreement protocol using the elliptic curve cryptography(ECC).We show that the proposed protocol meets common security requirements and is resistant to known security ***,we prove that the proposed scheme satisfies the security features using the Automated Validation of Internet Security Protocols and Applications(AVISPA)formal verification tool and On-the fly Model-Checker(OFMC)and ATtack SEarcher(ATSE)model *** have also proved the security of the session key exchange of our protocol using theReal orRandom(RoR)***,the comparison of our scheme with similar methods shows its superiority.

关键词： Satellite communications authentication session key agreement secure communication security protocols formal verification

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

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

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

Synthesis,characterization and application of BiVO_4 photoanode for photoelectrochemical oxidation of chlorate

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Chinese Journal of Catalysis 2017年第4期38卷 710-716页

作者： seyed Ghorban hosseini Saeid Safshekan Department of Chemistry Malek Ashtar University of Technology P. O. Box 16765‐3454 Tehran Iran Electroanalytical Chemistry Research Laboratory Faculty of Chemistry University of Mazandaran Babolsar Iran

A high‐quality polycrystalline bismuth vanadate(BiVO4)film was prepared on a fluorine‐doped tinoxide substrate via a facile two‐step strategy involving electrodeposition and annealing *** morphology and structural characterization of the resulting film were investigated by differentmethods including scanning electron microscopy,transmission electron microscopy,X‐ray diffraction(XRD),and Fourier transform infrared,ultraviolet‐visible(UV‐vis)absorption,and *** patterns as well as optical measurements revealed that BiVO4film crystallizedwith a pure monoclinic scheelite *** prepared BiVO4film was used for heterogeneousoxidation of chlorate ions in aqueous solution via electrochemical(EC),photochemical(PC),andphotoelectrochemical(PEC)*** decrease in concentration of chlorate was monitoredusing UV‐vis absorption *** results revealed that BiVO4could effectively performchlorate oxidation under light irradiation through a PEC *** kinetics of chlorate oxidationwas consistent with a first‐order reaction,and the rate constant for the PEC process was found to bemuch higher than those of EC and ***,a possible photocatalytic oxidation mechanismfor chlorate mainly based on the formation of perchlorate ions is proposed.

关键词： Bismuth vanadate Photocatalysis Electron‐hole pair Chlorate oxidation Photochemical reaction

Soil loss and displacement by heavy equipment in forest road subgrading projects

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International Journal of Sediment Research 2009年第2期24卷 227-235页

作者： Aidin PARSAKHOO seyed Ataollah hosseini Majid LOTFALIAN Hamid JALILVAND M.Sc. Student of Forest Engineering Faculty of Natural ResourcesMazandaran University Department of Forestry Faculty of Natural ResourcesMazandaran University

Forest soil is an important component of the natural environment,and is a primary medium for many biological activities. In this study,soil loss and displacement by excavator and bulldozer(heavy equipments) were measured on cut and fills slopes of forest roads located in Mazandaran province,Iran. The volumes of soil losses were estimated by prismoidal analyses of cut and fill slopes deformation between two time treatments(under subgrading and two years later) in slope classes of 30-50% and 50-70%. Weights of soil losses were calculated by multiplying the volumes of soil losses(cm3) to the general bulk density(1.3g/cm3) . Soil displaced area by heavy equipment was evaluated according to earth working width. Results indicated that heavy equipment has significant effect on deformation of cut slope gradient and fill slope length(p<0.0001) . During the two-year period,the cut(p<0.0002) and fill(p<0.0001) slope gradients were significantly deformed in different slope classes. The average soil loss by excavator and bulldozer were 160.35 t/ha·yr and 429.09 t/ha·yr,respectively. Moreover,the soil displaced area during the subgrading process by bulldozer was greater than excavator in both two slope classes(p<0.05) . Soil loss and displacement in forest roads can be reduced by applying powerful excavators in subgrading project,especially in steep terrains.

关键词： Soil losses Soil displacement Heavy equipment Forest road Subgrading

Biomechanical assessment of new surgical method instead of kyphoplasty to improve the mechanical behavior of the vertebra:Micro finite element study

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World Journal of Orthopedics 2017年第11期8卷 829-835页

作者： seyed Aref hosseini Faradonbeh Nima Jamshidi Department of Biomedical Engineering Faculty of Engineering University of Isfahan

AIM To reduce post treatments of kyphoplasty, as a common treatment for osteoporotic *** This study suggests a new method for treating vertebrae by setting the hexagonal porous structure instead of the rigid bone cement mass in the kyphoplasty(KP). The KP procedure was performed on the fresh ovine vertebra of the level L1. Micro finite element modeling was performed based on micro computed tomography of ovine trabecular cube. The hexagonal porous structure was set on one cube instead of the bone cement mass. For the implant designing, two geometrical parameters were considered: Spacing diameter and *** The results of micro finite element analyses indicated the improvement in the mechanical behavior of the vertebra treated by the hexagonal porous structures, as compared to those treated by vertebroplasty(VP) and KP under static loading. The improvement in the mechanical behavior of the vertebra, was observed as 54% decrease in the amount of maximum Von Misses stress(improvement of stress distribution), in trabecular cube with embedded hexagonal structure, as compared to VP and KP. This is comparable to the results of the experimental study already performed; it was shown that the improvement of mechanical behavior of the vertebra was observed as: 83% increase in the range of displacements before getting to the ultimate strength(increasing the toughness) after setting hexagonal pearls inside vertebrae. Both the material and geometry of implant influenced the amount of Von Mises stress in the *** The new proposed method can be offered as a substitute for the KP. The implant geometry had a more obvious effect on the amount of Von Mises stress, as compared to the implant material.

关键词： Vertebroplasty Kyphoplasty Micro finite element modeling Hexagonal porous structure Von mises stress