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Prediction of the soil erosion in a forest and sediment yield from road network through GIS and SEDMODL

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International Journal of Sediment Research 2014年第1期29卷 118-125页

作者： Aidin PARSAKHOO Majid LOTFALIAN Ataollah KAVIAN seyed Ataollah hosseini Department of Forestry Gorgan Agricultural Sciences and Natural Resources University Department of Watershed Management Sari Agricultural Sciences and Natural Resources University Department Forestry Sari Agricultural Sciences and Natural Resources University University of Tehran

This study was conducted to classify water erosion risk for a deciduous forest and to predict the amount of sediment yield from forest road *** in combination with AHP was used for determining the soil erosion risk degrees of ***,sediment yield from forest roads with gravel and asphalted surfacing was estimated using *** simulator was used in calibration and validation process of *** showed that47.9%of forest soil is classified from moderate to very high vulnerability.32.3%of roads were located in soil erosion risk class of very *** class is generally found in the eastern region of forest,while areas with very low risk are found in the south western part.14.6%of the forest roads were ranked as having very low sediment *** 61 segments out of 339 segments of forest road network delivered sediment to the ravine *** estimated annual sediment yield for all of road sections by SEDMODL and rainfall simulator were 10,935.45 and10,509.29 g m,*** of the calibration and validation process showed that the variation accounted for in the predicted values by SEDMODL with the observed values under rainfall simulation was 3.90%.Best management practices(BMP) must be considered for the areas with high degrees of erosion risk.

关键词： Soil erosion Forest road GIS SEDMODL

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

Fabrication and Characterization of Willemite Scaffolds Using Corn Stalk as a Novel Bio Template for Bone Tissue Engineering Applications

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Journal of Bionic Engineering 2023年第1期20卷 16-29页

作者： Zahra Yahay seyed Mehdi Mirhadi Fariborz Tavangarian Department of Cellular Biotechnology Cell Science Research CenterRoyan Institute for BiotechnologyACECRIsfahan81593-58686Iran Department of Materials Engineering Shahreza BranchIslamic Azad UniversityShahrezaIsfahan86145-311Iran Mechanical Engineering Program School of ScienceEngineering and TechnologyPennsylvania State UniversityHarrisburgMiddletownPA17057USA

In this paper,we used Corn Stalk(CS)as a renewable and economical bio template to fabricate willemite scaffolds with the potential application in skull bone *** was used as a sacrificial template to synthesize the *** scaffolds with the chemical formula of Zn2SiO4 and pore size in the range of 3 to 10µm could be successfully synthesized by soaking CS in the willemite solution for 24 h and sintering at 950°C for 5 *** porosity of the samples was controlled by the soaking time(between 12 and 48 h)in the willemite solution from 5 to 35%,*** properties of these scaffolds showed a good approximation with cranial bone *** addition,cytotoxicity assays(MTT)were performed on Human Bone Marrow Stromal cells(HBMSc)and A172 human glioblastoma cell lines by direct and indirect culture methods to estimate their toxicity for bone and nerve cells,*** Phosphatase(ALP)activity and DAPI/Phalloidin cell staining were also performed to investigate the efficiency of the scaffolds for bone tissue engineering *** results showed that the scaffolds had good biocompatibility with both HBMSC and A172 cells,noticeable improvement on ALP activity,and great apatite formation ability in Simulated Body Fluid(SBF).All the evidence ascertained that willemite scaffolds made by corn stalks could be a useful candidate for bone tissue engineering applications.

关键词： Corn stalk Bio template Bioactive ceramics-Scaffolds Bone tissue engineering

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

Coupled quantum molecular cavity optomechanics with surface plasmon enhancement:comment

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Photonics Research 2020年第11期8卷 1783-1785页

作者： seyed mahmoud Ashrafi Narjes Taghadomi Alireza Bahrampour Rasoul Malekfar Department of Physics Tarbiat Modares UniversityTehranIran Department of Physics Sharif UniversityTehranIran

We have found an incorrect formula to estimate the root mean square(rms)amplitude of the molecular vibration in the molecular optomechanics systems reported by *** et al.[***.5,450–456(2017)[CrossRef]].In contrast with common optomechanical systems,the equilibrium position for molecular optomechanics systems used in the letter cannot be achieved by the equipartition ***,we achieve the effective temperature of molecules and then provide a corrected formula for the estimation of the rms amplitude of molecular *** defined effective temperature into our new formula,we show that the minimal measurable force is(𝐹≈1.7×10^(−14) N),which it is 1 order bigger than the result of the main paper,and it is also in accordance with numerical calculation through the Lindblad master equation.

关键词： equation. measurable quantum

A novel control strategy based on a look-up table for optimal operation of MTDC systems in post-contingency conditions

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Protection and Control of Modern Power Systems 2022年第1期7卷 40-50页

作者： seyed Mohsen Alavi Reza Ghazi Department of Electrical Engineering Ferdowsi University of MashhadMashhadIran

Multi terminal VSC-HVDC systems are a promising solution to the problem of connecting offshore wind farms to AC *** power sharing and appropriate control of DC-link voltages are essential and must be maintained dur-ing the operation of VSC-MTDC systems,particularly in post-contingency *** traditional droop control methods cannot satisfy these requirements,and accordingly,this paper proposes a novel centralized control strategy based on a look-up table to ensure optimal power sharing and minimum DC voltage deviation immediately during post-contingency conditions by considering converter *** also reduces destructive effects(e.g.,frequency devia-tion)on onshore AC grids and guarantees the stable operation of the entire MTDC *** proposed look-up table is an array of data that relates operating conditions to optimal droop coefficients and is determined according to N-1 contingency analysis and a linearized system *** constraints and contingencies such as wind power changes,converter outage,and DC line disconnection are considered in its formation *** performed on a 4-terminal VSC-MTDC system in the MATLAB-Simulink environment validate the effectiveness and superiority of the proposed control strategy.

关键词： Optimal power sharing DC voltage deviation Adaptive droop control Multi-terminal HVDC(MTDC) Voltage source converter(VSC)

Automatic recognition of sonar targets using feature selection in micro-Doppler signature

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Defence Technology（防务技术） 2023年第2期20卷 58-71页

作者： Abbas Saffari seyed-Hamid Zahiri Mohammad Khishe Department of Electrical Engineering University of BirjandBirjandIran Department of Electrical Engineering Imam Khomeini Marine Science UniversityNowshahrIran

Currently,the use of intelligent systems for the automatic recognition of targets in the fields of defence and military has increased *** primary advantage of these systems is that they do not need human participation in target recognition *** paper uses the particle swarm optimization(PSO)algorithm to select the optimal features in the micro-Doppler signature of sonar *** microDoppler effect is referred to amplitude/phase modulation on the received signal by rotating parts of a target such as *** different targets'geometric and physical properties are not the same,their micro-Doppler signature is *** Inconsistency can be considered a practical issue(especially in the frequency domain)for sonar target *** using 128-point fast Fourier transform(FFT)for the feature extraction step,not all extracted features contain helpful *** a result,PSO selects the most optimum and valuable *** evaluate the micro-Doppler signature of sonar targets and the effect of feature selection on sonar target recognition,the simplest and most popular machine learning algorithm,k-nearest neighbor(k-NN),is used,which is called k-PSO in this paper because of the use of PSO for feature *** parameters measured are the correct recognition rate,reliability rate,and processing *** simulation results show that k-PSO achieved a 100%correct recognition rate and reliability rate at 19.35 s when using simulated data at a 15 dB signal-tonoise ratio(SNR)angle of 40°.Also,for the experimental dataset obtained from the cavitation tunnel,the correct recognition rate is 98.26%,and the reliability rate is 99.69%at ***,the k-PSO has an encouraging performance in automatically recognizing sonar targets when using experimental datasets and for real-world use.

关键词： Micro-Doppler signature Automatic recognition Feature selection k-NN PSO

Effect of granulated rubber on shear strength of fine-grained sand

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第5期9卷 936-944页

作者： seyed mahmoud Anvari Issa Shooshpasha Saman Soleimani Kutanaei Department of Civil Engineering Babol University of Technology Babol Iran

Review of the literature related to the mixture of shredded tire and sand shows that,despite of the increase in shear strength due to addition of tire chips,granulated rubber causes reduction in shear strength of *** this study,the shear behavior of mixtures of fine-grained sand and 1-5 mm granulated rubber is *** direct shear tests were conducted on sandegranulated rubber mixtures with various rubber contents(0%,5%,10%,20% and 30%) at different relative densities(50%,70% and 90%) and different normal stresses(34.5 kPa,54.5 kPa,74.5 kPa and 104.5 kPa).The obtained results show that the granulated rubber improves the shear strength of fine-grained sand at medium relative density and low normal *** degree of improvement in shear strength is a function of rubber content,relative density and normal *** results show that at relative density of 50%,by adding 5% granulated rubber,the internal friction angle of sand increases from 35.1° to 39.2°.However,at relative densities of 70% and 90%,addition of granulated rubber to sand decreases its internal friction *** results also indicate that the behavior of sand becomes more ductile with increasing granulated rubber *** granulated rubber leads to greater yielding strain and less tangent stiffness of *** maximum dilation angle decreases with the decrease in granulated rubber *** stress ratio of sample at critical state(ψ= 0°) decreases with increasing granulated rubber content.

关键词： Granulated rubber Fine-grained sand Relative density Shear strength

Fuzzy coloured petri nets‐based method to analyse and verify the functionality of software

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CAAI Transactions on Intelligence Technology 2023年第3期8卷 863-879页

作者： Mina Chavoshi seyed Morteza Babamir Department of Software Engineering University of KashanKashanIran

Some types of software systems,like event‐based and non‐deterministic ones,are usually specified as rules so that we can analyse the system behaviour by drawing inferences from firing the ***,when the fuzzy rules are used for the specification of non‐deterministic behaviour and they contain a large number of variables,they constitute a complex form that is difficult to understand and infer.A solution is to visualise the system specification with the capability of automatic rule *** this study,by representing a high‐level system specification,the authors visualise rule representation and firing using fuzzy coloured Petri‐***,several fuzzy Petri‐nets‐based methods have been presented,but they either do not support a large number of rules and variables or do not consider significant cases like(a)the weight of the premise's propositions in the occurrence of the rule conclusion,(b)the weight of conclusion's proposition,(c)threshold values for premise and conclusion's propositions of the rule,and(d)the certainty factor(CF)for the rule or the conclusion's *** considering cases(a)-(d),a wider variety of fuzzy rules are *** authors applied their model to the analysis of attacks against a part of a real secure water treatment *** another real experiment,the authors applied the model to the two scenarios from their previous work and analysed the results.

关键词： fuzzy logic software engineering verification