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Risk Assessment of Vegetation Degradation Using Geographic Information System: A Case Study of Qareh Aghaj Basin,Iran

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Journal of Resources and Ecology 2018年第5期9卷 477-483页

作者： Masoud MASOUDI parviz JOKAR Department of Natural Resources and Environmental Engineering College of AgricultureShiraz UniversityShirza ***lran

The entire land of Southern Iran faces problems arising out of various types of land degradation of which vegetation degradation forms one of the major types. The Qareh Aghaj basin（1 265 000 ha）,which covers the upper reaches of Mond River,has been chosen for a test risk assessment of this type. The different kinds of data for indicators of vegetation degradation were gathered from the records and published reports of the governmental offices of Iran. A new model has been developed for assessing the risk of vegetation degradation. Taking into consideration nine indicators of vegetation degradation the model identifies areas with ＂Potential Risk＂（risky zones） and areas of ＂Actual Risk＂ as well as projects the probability of the worse degradation in future. The preparation of risk maps based on the GIS analysis of these indicators will be helpful for prioritizing the areas to initiate remedial measures. By fixing the thresholds of severity classes of the nine indicators a hazard map for each indicator was first prepared in GIS. The risk classes were defined on the basis of risk scores arrived at by assigning the appropriate attributes to the indicators and the risk map was prepared by overlaying nine hazard maps in the GIS. Areas under actual risk have been found to be widespread（78%） in the basin and when the risk map classified into subclasses of potential risk with different probability levels the model projects a statistical picture of the risk of vegetation degradation.

关键词： vegetation degradation GIS indicator actual risk potential risk

Facies Analysis, Depositional Environment and Diagenetic Features of the Qom Formation in the Saran Semnan, Central Iran

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Open Journal of Geology 2016年第6期6卷 349-362页

作者： Fereshteh Karami-Movahed Mohsen Aleali parviz Ghazanfari Faculty of Basic Sciences Department of Geology Islamic Azad University North Tehran Branch Tehran Iran Department of Geology Science and Research Branch Islamic Azad University Tehran Iran Department of Geology Imam Khomeini International University of Science Qazvin Iran

In this study, to identify and analyze facies of depositional environment and depositional model of Qom Formation, stratigraphic Saran Section (southwest of Semnan) was selected. Qom Formation in Saran section includes about 380 meters of conglomerate at the base, chalk, limestone, marl, and shale. Petrographic studies with facies analysis have led to the identification of 12 microfacies, these microfacies have been deposited in four facies groups including tidal flat, lagoon, barrier and open marine. Study of horizontal and vertical facies changes and their comparison with recent and ancient environments reveals that Qom Formation in this section relates to shallow marine environment and its facies were deposited in a shelf carbonate platform and are comparable with contemporary shelf platforms such as Florida and old shelf platforms such as Mozduran. The most important diagenetic processes affecting the studied section include micritization, bioturbation, cementation, dissolution, neomorphism, fracturing, mechanical and chemical compaction, hematitization and dolomitization. These processes have formed in marine, meteoric and burial diagenetic environments.

关键词： Facies Analysis Depositional Environment Qom Formation Saran Semnan Centeral Iran

Sound Scattering From Rough Bubbly Ocean Surface Based on Modified Sea Surface Acoustic Simulator and Consideration of Various Incident Angles and Sub-surface Bubbles＇ Radii

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Journal of Marine Science and Application 2016年第3期15卷 275-287页

作者： Alireza Bolghasi parviz Ghadimi Mohammad A. Feizi Chekab Department of Marine Technology Amirkabir University of Technology Tehran 15875-4413 Iran

The aim of the present study is to improve the capabilities and precision of a recently introduced Sea Surface Acoustic Simulator(SSAS) developed based on optimization of the Helmholtz–Kirchhoff–Fresnel(HKF) method. The improved acoustic simulator, hereby known as the Modified SSAS(MSSAS), is capable of determining sound scattering from the sea surface and includes an extended Hall–Novarini model and optimized HKF method. The extended Hall–Novarini model is used for considering the effects of sub-surface bubbles over a wider range of radii of sub-surface bubbles compared to the previous SSAS version. Furthermore, MSSAS has the capability of making a three-dimensional simulation of scattered sound from the rough bubbly sea surface with less error than that of the Critical Sea Tests(CST) experiments. Also, it presents scattered pressure levels from the rough bubbly sea surface based on various incident angles of sound. Wind speed, frequency, incident angle, and pressure level of the sound source are considered as input data, and scattered pressure levels and scattering coefficients are provided. Finally, different parametric studies were conducted on wind speeds, frequencies, and incident angles to indicate that MSSAS is quite capable of simulating sound scattering from the rough bubbly sea surface, according to the scattering mechanisms determined by Ogden and Erskine. Therefore, it is concluded that MSSAS is valid for both scattering mechanisms and the transition region between them that are defined by Ogden and Erskine.

关键词： Modified SSAS method scattering strength rough bubbly sea surface wind speed sub-surface bubble plume surface scattering mechanisms

Sea Surface Effects on Sound Scattering in the Persian Gulf Region Based on Empirical Relations

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Journal of Marine Science and Application 2015年第2期14卷 113-125页

作者： parviz Ghadimi Alireza Bolghasi Mohammad A. Feizi Chekab Department of Marine Technology Amirkabir University of Technology Tehran 15875-4413 Iran

In this paper, sound scattering from the sea surface in the Persian Gulf region is investigated. Chapman-Harris and Ogden-Erskine empirical relations coupled with perturbation theory are implemented. Based on the Ogden and Erskine＇s experiments, sound scattering from the sea surface has three different regimes in which two mechanisms of surface roughness and subsurface bubble clouds are involved. Ogden-Erskine＇s scattering relation which consists of perturbation theory and Chapman-Harris＇s scattering terms are verified by the experimental data of Critical Sea Tests 7. Subsequently, wind speed in the Persian Gulf is provided based on three data bases of Arzanah station, ERA40, and PERGOS. Accordingly, surface scattering strength in the Persian Gulf region is calculated at different grazing angles, frequencies and provided wind speeds. Based on the resulted values of scattering strength, scattered intensity from the sea surface is also studied. These studies indicate that both scattering strength and scattered intensity generally increase as grazing angle, frequency and wind speed increase.

关键词： surface scattering strength scattered intensity seasurface effects Persian Gulf sound scattering empirical relation perturbation theory

A comparison between the efficiency of manufacturing factors on the governmental(Quasi-governmental) and private companies in the stock exchange's of Iran

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A comparison between the efficiency of manufacturing factors...

Determining the Optimal Algorithm to Locate the Best Place for Earthquake Refugee Camps: A Case Study for Tehran, Iran

2012 International Conference on Economics, Business and Marketing Management（CEBMM 2012）

作者： parviz Saeidi Neda Jorjani Deprtment of Business Administration faculty of accounting and managementIslamic Azad UniversityAliabad Katoul BranchGolestanIran Government Management the financial trends Islamic Azad UniversityAliabad Katoul BranchGolestanIran

This study compares the productivity of production factors between the governmental(Quasigovernmental) and private companies stock exchange in Iran,*** study in its aim is application-base and in its method,is a survey of scientific-comparison which compares the governmental(Quasigovernmental) and private *** study compared the productivity of production factors in the timeframe from 2001 to *** order to analyze the research hypotheses,using the paired T-test and analysis of variance,Pearson's linear correlation coefficient was *** results showed the efficiency of production factors between sectors in the governmental(Quasi-governmental) and private companies,there are significant differences.

关键词： productivity,efficiency factors of production,governmental(Quasi-governmental) and private companies

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Positioning 2014年第4期5卷 97-106页

作者： Javad Sadidi Reyhaneh Saeedi Aliasghar Torahi parviz Zeaiean Firuzabadi Department of GIS and Remote Sensing Faculty of Geography Kaharazmi University Tehran Iran Kharazmi University Tehran Iran Department of Remote Sensing and GIS Faculty of Geographical Sciences Kharazmi University Tehran Iran

Iran is one of the regions which are most prone for earthquakes annually having a large number of financial and mortality and financial losses. Every year around the world, a large number of people lose their home and life due to natural disasters such as earthquakes and floods. It is necessary to provide and specify some suitable places for settling the homeless people before occurrence of the earthquake, one of the most important factors in crisis planning and management. GIS has a vital role in crisis management. By using GIS, it would be possible to manage the spatial data and reach several goals by making use of the analyses existing in it. Among the applications of GIS in crisis management there is location of suitable and safe place for settling the injured people after the occurrence of the earthquake. With respect to the importance of specifying weight to the required criteria so as to find safe and suitable places for settling the injured people optimally, the present research is about to show the algorithms AHP, Fuzzy, TOPSIS and OWA as being suitable in terms of accuracy and speed. We discuss several natural and human criteria to choose the optimal place considering the importance of the issue. At the end we did a comparison among these methods. According to the features of each method, combined methods of Fuzzy and AHP can create high ability in locating for resettling of victims. So we can improve all these methods before being combined by described methods.

关键词： Crisis Management Temporary Settlement Earthquake Hierarchical Process Fuzzy Process TOPSIS Process OWA Process Geographic Information System (GIS)

The impact of ipsilateral testicular atrophy on semen quality and sperm DNA fragmentation response to varicocele repair

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Asian Journal of Andrology 2021年第2期23卷 146-149页

作者： parviz K Kavoussi Natasha Abdullah Melissa S Gilkey Caitlin Hunn G Luke Machen Shu-Hung Chen Keikhosrow M Kavoussi Amy Esqueda J David Wininger Shahryar K Kavoussi Austin Fertility and Reproductive Medicine/Westlake IVF 300 Beardsley LaneBuilding BSuite 200AustinTX 78746USA

Varicoceles adversely impact semen quality and sperm DNA fragmentation,which typically improve with surgical *** men with varicoceles have ipsilateral testicular atrophy due to damage from the *** study assessed semen quality and the sperm DNA fragmentation index(DFI)response to varicocele repair in men with ipsilateral testicular atrophy(TA)versus men with no testicular atrophy(NTA).Semen parameter values and DFI in both groups were compared preoperatively and *** Mann-Whitney U test and the Wilcoxon signed-rank test were used where *** were 20 men in the TA group and 121 men in the NTA group with no difference in age,varicocele grade,or preoperative semen parameter values between the two *** NTA group had a higher preoperative DFI than the TA *** groups showed improvement in semen quality postoperatively,only the TA group showed a significant improvement in DFI,whereas the NTA group showed significant improvements in several parameter values and *** change from preoperative to postoperative parameter values when comparing the two groups revealed a difference in total sperm motile count and DFI,with a larger mean improvement in the NTA group than in the TA *** TA and NTA groups showed improved semen quality and DFI after varicocele repair,but the NTA group had more improvement than the TA ***,only total motile count(TMC)and DFI had a significantly greater mean change in preoperative to postoperative response in the NTA group than in the TA group.

关键词： spermatozoa testicular atrophy varicocele

A Significant Look at the Effects of Persian Gulf Environmental Conditions on Sound Scattering Based on Small Perturbation Method

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Journal of Marine Science and Application 2015年第4期14卷 413-424页

作者： parviz Ghadimi Alireza Bolghasi Mohammad A. Feizi Chekab Rahim Zamanian Department of Marine Technology Amirkabir University of Technology Tehran 15875-4413 Iran International Campus-Mechanical Engineering Group Amirkabir University of Technology Tehran 15875-4413 Iran

The main goal of this paper is to investigate sound scattering from the sea surface, by Kuo＇s small perturbation method （SPM）, in the Persian Gulf＇s environmental conditions. Accordingly the SPM method is reviewed, then it is demonstrated how it can accurately model sound scattering from the sea surface. Since in Kuo＇s approach, the effects of surface roughness and sub-surface bubble plumes on incident sounds can be studied separately, it is possible to investigate the importance of each mechanism in various scattering regimes. To conduct this study, wind and wave information reported by Arzanah station as well as some numerical atmospheric models for the Persian Gulf are presented and applied to examine sound scattering from the sea surface in the Persian Gulf region. Plots of scattering strength by Kuo＇s SPM method versus grazing angle for various frequencies, wave heights, and wind speeds are presented. The calculated scattering strength by the SPM method for various frequencies and wind speeds are compared against the results of critical sea tests 7 （CST-7）. The favorable agreement achieved for sound scattering in the Persian Gulf region is indicative of the fact that the SPM method can quite accurately model and predict sound scattering from the sea surface.

关键词： sea surface Persian Gulf small perturbation method (SPM) wind rose plots wave rose plots sound scattering surface roughness sub-surface bubble plumes

Collocation Method for Nonlinear Volterra-Fredholm Integral Equations

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Open Journal of Applied Sciences 2012年第2期2卷 115-121页

作者： Jafar Ahmadi Shali parviz Darania Ali Asgar Jodayree Akbarfam Department of Mathematics and Computer Science University of Tabriz Tabriz Iran Department of Mathematics Faculty of Science Urmia University Urmia Iran

A fully discrete version of a piecewise polynomial collocation method based on new collocation points, is constructed to solve nonlinear Volterra-Fredholm integral equations. In this paper, we obtain existence and uniqueness results and analyze the convergence properties of the collocation method when used to approximate smooth solutions of Volterra- Fredholm integral equations.

关键词： Collocation Method Nonlinear Volterra-Fredholm Integral Equations Convergence Analysis Chelyshkov Polynomials