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Self-magnetism and Persistent Photoconductivity

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Communications in Theoretical Physics 2008年第10期50卷 999-1002页

作者： Majid Vaezzadeh WANG Quan Mohammadreza Saeidi Araz Seeabi Department of Physics K.N. Toosi University 41 Shahid Kavian St. 15418-49611 Tehran Iran Department of Mechanical and Manufacturing Engineering University of Manitoba Winnipeg Manitoba Canada R3T 5V6

Persistent photoconductivity has been investigated by various models, among which the Macroscopic Barrier model, Large-Lattice-Relaxation model, and Random Local Potential Fluctuations model are mostly well known. Although the three well-known models have played important roles in describing the persistent photoconductivity, they are not the principal cause of persistent photoconductivity. In this paper a classical model originated from ＂selfmagnetism of electron gas＂ is proposed to illustrate the persistent photoconductivity phenomenon. This classical model is based on electron gas pulsation, which depends on the charge density. Different concentrations of current carriers create different frequencies in the system, and thus the system is sensitive to different wave lengths of incident light. Then the construction of different detectors can be possible for different wave lengths of incident light.

关键词： self-magnetism persistent photoconductivity electron gas pulsation

Tracing suspended and bed sediments during high and low water periods using geochemical characteristics-Case study:Vazrood watershed,northern Iran

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Journal of Mountain Science 2024年第2期21卷 470-483页

作者： KARIMI Nabiyeh GHOLAMI Leila kavian Ataollah KHALEDI DARVISHAN Abdulvahed Department of Watershed Management Faculty of Natural ResourcesSari Agricultural Sciences and Natural Resources UniversitySari ***Iran Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor ***Iran

Complete and comprehensive information about sediment dynamic and identification of hotspots of sediment production and transport are necessary for understanding the erosion processes and increasing the efficiency of soil and water conservation *** studies used the sediment fingerprint techniques to investigate the contribution of different sources in suspended and bed sediment yield of the ***,the contribution of various land use/land covers in suspended and bed sediment yield for the great Caspian Sea basin is in an aura of ambiguity and the present study was conducted to gather information about an important part of this area in northern Iran,where rangelands are located upstream of Hyrcanian forests and dense agricultural lands are located *** surface soil of different land use/land covers including forest,rangeland,agriculture and streambank lands were sampled in 30 *** and bed sediments were sampled in the watershed outlet in two high and low water *** characteristics of soil and sediment samples containing 59 elements were measured using ICP-OES GBC *** reliable and suitable tracers from 59 elements were then selected using Range test,Kruskal-Wallis and Discriminant Function Analysis,respectively,in FingerPro package of R *** results showed that for suspended sediment,streambank and rangeland had the highest contributions of 86.2%and 47.5%,respectively,in two high and low water *** bed sediment,in two high and low water periods,rangeland and streambank had the highest contributions of 73.8%and 84.4%,*** use change and especially human activities such as agriculture,road construction and development of residential areas along the main river riparian zone has led to a significant increase in suspended and bed sediments.

关键词： Caspian Sea basin FingerPro Geochemistry Sediment transport Tracer combination

New formalism in evaluation of the ground and few excited states of Hubbard chain nanostructures

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New formalism in evaluation of the ground and few excited st...

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

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作者： E.Faizabadi M.Soleimani Department of Physics Iran University of Science and Technology Department of Physics K.N.Toosi UniversityNo.41Shahid Kavian AlleyShahid Mojtabaei Str.Shariati Ave.15875-4416TehranIran

A new,simple and efficient method is presented for calculation of the ground and a few excited states of Hubbard chain *** using this method,the photoemission spectral function for organic charge transfer salt TTF-TCNQ,is *** a chain with maximum 70 sites the result is in good agreement with the previous works but there is a difference for further number of sites in the chain,which is discussed in the text with all the *** also show that a source of errors in density matrix renormalization group method for a one dimensional chain is the deficiency of the matrix product scheme for generating the desired states of the linear chain.

关键词： Photoemission spectral function,TTF-TCNQ ground state,Hubbard

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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

Autonomous fault-diagnosis and decision-making algorithm for determining faulty nodes in distributed wireless networks

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Frontiers of Information Technology & Electronic Engineering 2016年第9期17卷 885-896页

作者： Adel KHOSRAVI Yousef SEIFI kavian Electrical Engineering Department Faculty of Engineering Shahid Chamran University of Ahvaz

In this paper, we address fault-diagnosis agreement(FDA) problems in distributed wireless networks(DWNs) with arbitrary fallible nodes and healthy access points. We propose a new algorithm to reach an agreement among fault-free members about the faulty ones. The algorithm is designed for fully connected DWN and can also be easily adapted to partially connected networks. Our contribution is to reduce the bit complexity of the Byzantine agreement process by detecting the same list of faulty units in all fault-free members. Therefore, the malicious units can be removed from other consensus processes. Also, each healthy unit detects a local list of malicious units, which results in lower packet transmissions in the network. Our proposed algorithm solves FDA problems in 2t+1 rounds of packet transmissions, and the bit complexity in each wireless node is O(nt+1).

关键词： Fault diagnosis Decision making Byzantine agreement Distributed wireless networks Consensus

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

Comments on Asian Stroke Criteria

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Neural Regeneration Research 2009年第11期4卷 958-960页

作者： kavian Ghandehari Department of Neurology Ghaem HospitalFaculty of MedicineMashhad University of Medical Sciences

The Asian Stroke Criteria （ASC） was developed to detect etiology and topography of brain infarction. The ASC was designed by stroke neurologists and approved by the university of Alberta, Canada in 2003. In the first validation step, inter-rater reliability of ASC was evaluated. The inter-rater agreement, according to the ASC system, is much higher than other classifications with moderate inter-observer reliability. In the second validation step, ASC has been used successfully in Khorasan stroke registries.

关键词： stroke infarction classification etiology

Effect of storm pattern on soil erosion in damaged rangeland;field rainfall simulation approach

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Journal of Mountain Science 2021年第3期18卷 706-715页

作者： Leila GHOLAMI Abdulavahed KHALEDI DARVISHAN Veliber SPALEVIC Artemi CERDà Ataollah kavian Department of Watershed Management Faculty of Natural ResourcesSari Agricultural Sciences and Natural Resources University(SANRU)Sari 48181-66996Iran Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor 46417-76489Iran Department of Geography Faculty of Philosophy of the University of MontenegroNiksic 81400Montenegro Soil Erosion and Degradation Research Group Departament de Geografia.Universitat de València.Blasco Ibà?ez 28 Valencia 46010Spain

Raindrop size,rainfall intensity and runoff discharge affect the detachment and transportation of soil *** these three factors,the rainfall intensity seems to be more important because it can change other two *** patterns can be determined by changing the rainfall intensity during the ***,the objective of this research is to test the influence of storm pattern on runoff,soil erosion and sediment concentration on a rangeland soil slope under field rainfall *** storm rainfall intensity patterns were selected for examining the effects of variations in storm event characteristics on soil erosion *** selected storm patterns were:I(45,55 and 70 mm h-1);II(45,70 and 55 mm h-1);III:(70,55 and 45 mm h-1);and IV(55,45 and 70 mm h1).The last pattern is a new one instead of the uniform pattern which has been sufficiently studied in previous *** experiments were conducted in field plots(in Kojour watershed,Mazandaran Province,Iran)with an area of one square meter and an constant slope gradient of 18%,surrounded by galvanised *** the nonuniform prioritization of the storm patterns for the studied variables,time to runoff(I>II>IV>III),runoff volume(III>IV>II>I),sediment concentration(IV>III>I>II)and soil erosion(III>IV>II>I)),it can be generally inferred that each pattern has specific effect on soil erosion processes during a *** results of the general linear model(GLM)test indicated that the effects of storm pattern on time to runoff,total runoff volume,runoff coefficient and soil erosion were significant at a level of 99%.The Duncan test showed that the storm patterns can be divided into three groups of III,IV;II;I(for time to runoff),I,II;IV,III(for runoff coefficient),and I;II;IV,III(for runoff volume and soil erosion).

关键词： Plot scale Runoff coefficient Soil erosion Storm patterns Time to runoff

Runoff and sediment concentration of different parts of a road in Hyrcanian forests

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Forestry Studies in China 2013年第2期15卷 144-151页

作者： Majid LOTFALIAN Aidin PARSAKHOO Ataollah kavian Seyed Ataollah HOSSEINI Department of Forestry Faculty of Natural Resources Sari Agricultural Sciences and Natural Resources UniversitySari 737 Iran Department of Forestry Faculty of Forest Science Gorgan Agricultural Sciences and Natural Resources UniversityGorgan 386 Iran Department of Watershed Management Faculty of Natural Resources Sari Agricultural Sciences and Natural Resources UniversitySari 737 Iran

Road prisms, such as cutslopes, fillslopes and road surfaces, can be important contributors of sediment to streams in forested watersheds. In this study rainfall simulations were carried out on cutslopes, fillslopes, road surfaces and forest grounds in hardwood forests of Lolet and Lat Talar, Iran. Water at intensity of 32.4 mm·h-1 was sprayed from a nozzle onto a square area of 0.48 m2. Runoff was collected by water gauge every 4 min and then runoff and sediment parameters were measured in each plot. Results indicated that on road surfaces, the runoff coefficient was 63.28%. On the cutslopes and fillslopes, the runoff coefficients were 35.14% and 10.23%, respectively. On the forest ground as a control, the runoff coefficient was 5.90%. Runoff volume was 2.73 mL·s^-1 on the road surfaces and 1.52 mL·s^-1 on cutslopes. On fillslopes the runoff volume was 0.44 mL·s^-1 and on the forest ground 0.25 mL·s^-1 The greatest rate of soil loss was found on the cutslope （280.79 g·m-2·h-1）. The total soil loss from the cutslopes was two times higher than that from the road surfaces and six times higher than that from the fillslopes. We conclude that cutslopes can be considered the main source of sediments in our study sites, but the function of road surface as a source of runoff generation is more important.

关键词： runoff soil loss road prism rainfall simulation Hyrcanian forest