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Spatio-temporal analysis of forest fire events in the Margalla Hills,Islamabad,Pakistan using socio-economic and environmental variable data with machine learning methods

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Journal of Forestry Research 2022年第1期33卷 183-194页

作者： Aqil Tariq Hong Shu Saima Siddiqui Iqra Munir alireza sharifi Qingting Li Linlin Lu State Key Laboratory of Information Engineering in SurveyingMapping and Remote SensingWuhan UniversityWuhan 430079HubeiPeople’s Republic of China Department of Geography University of the PunjabLahorePunjabPakistan Department of Surveying Engineering Faculty of Civil EngineeringShahid Rajaee Teacher Training UniversityTehranIran Airborne Remote Sensing Center Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094People’s Republic of China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094People’s Republic of China

Most forest fires in the Margalla Hills are related to human activities and socioeconomic factors are essential to assess their likelihood of *** study considers both environmental(altitude,precipitation,forest type,terrain and humidity index)and socioeconomic(population density,distance from roads and urban areas)factors to analyze how human behavior affects the risk of forest *** entropy(Maxent)modelling and random forest(RF)machine learning methods were used to predict the probability and spatial diffusion patterns of forest fires in the Margalla *** receiver operating characteristic(ROC)curve and the area under the ROC curve(AUC)were used to compare the *** studied the fire history from 1990 to 2019 to establish the relationship between the probability of forest fire and environmental and socioeconomic *** Maxent,the AUC fire probability values for the 1999 s,2009 s,and 2019 s were 0.532,0.569,and 0.518,respectively;using RF,they were 0.782,0.825,and 0.789,*** were mainly distributed in urban areas and their probability of occurrence was related to accessibility and human behaviour/*** principles for validation were greater in the random forest models than in the Maxent *** results can be used to establish preventive measures to reduce risks of forest fires by considering socio-economic and environmental conditions.

关键词： Forest fires Maxent GIS Disaster risk reduction Random forest machine learning Multi-temporal analysis

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微网中同步发电机非线性动力模型的抗扰一致跟踪研究

微网中同步发电机非线性动力模型的抗扰一致跟踪研究

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作者： alireza sharifi 上海交通大学

学位级别：硕士

本文针对多智能体同步发电机的状态估计及其一致性跟踪问题提出了一种基于滑模控制器的高增益观测器。由于同步发电机被并入到分布式发电机单元时,微电网的稳定性和可靠性会受到很大挑战,因此本文通过利用滑模控制器实现了有限时间下同... 详细信息

本文针对多智能体同步发电机的状态估计及其一致性跟踪问题提出了一种基于滑模控制器的高增益观测器。由于同步发电机被并入到分布式发电机单元时,微电网的稳定性和可靠性会受到很大挑战,因此本文通过利用滑模控制器实现了有限时间下同步发电机状态轨迹的收敛。此外,所提出的控制器还具有误差收敛速度快、抗干扰能力强等优点。另一方面,系统若要具备有效识别多智能体同步发电机非线性响应的复杂性,且通过为高增益观测器选择足够的增益可以消除超调现象,也需要一个快速而准确的从机状态估计器。本文所提方法在电力系统和控制科学中具有较强的创新性。可再生能源发电和微电网通常被其定义为一个高效率的互联或孤岛电力系统,其中一般包括负荷、存储设备和发电机。由于世界用电量的大幅增加、环境危机和电力稳定问题的凸显,可再生能源发电和微电网成为满足用户用电需求的重要解决方案。尽管分布式发电作为微型电网最重要的职责之一,正在成为一种新型的电能发电方法,但发电商的协同控制在保证系统各部分之间的最佳协作方面有着不可否认的优势。滑模控制器作为一种适当的非线性控制策略,可以实现非线性系统的动态控制,而高增益观测器则可以用来估计非线性系统的状态,保证效率和生产率。

关键词：微电网同步发电机多代理系统一致性跟踪滑模控制器高增益观测器

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Use of complementary and alternative medicine in pregnant women:A cross-sectional survey in the south of Iran

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Journal of Integrative Medicine 2019年第6期17卷 392-395页

作者： Naghmeh Yazdi alireza Salehi Mina Vojoud Mohammad Hossein sharifi Ayda Hoseinkhani Research Center for Traditional Medicine and History of Medicine Shiraz University of Medical Sciences71348-14336 ShirazIran Student Research Committee Shiraz University of Medical Sciences71348-14336 ShirazIran

Objective: The use of traditional medicine and complementary alternative medicine(TM/CAM) derived from herbal remedies or natural supplements is increasing worldwide, but there are limited data on the use of TM/CAM during pregnancy. Iran has various ethnic populations, and the usage of TM/CAM by the different ethnic groups has not been researched. The aim of this study is to understand the use of TM/CAM modalities in pregnant women of different ethnic groups in southern ***: This study was conducted in primary health care centers in Khuzestan Province, Iran, from May to August, 2016. A semi-structured valid questionnaire was used to gather information in pregnant women(n = 170).Results: About 46.5% of women in this study used TM/CAM during previous pregnancies. The majority(67%) of study participants were Arab. The Arab population showed increased use of TM/CAM during pregnancy(P = 0.014). Women with complications in former pregnancies had significantly higher incidence rate of TM/CAM use(65.8%) compared to the other group(39.6%)(P = 0.001).Conclusion: Understanding TM/CAM use and the associated factors in different ethnic groups of pregnant women will benefit the evaluation of the proper health policies and mother-infant health programs. This study contributes to the growing literature on TM/CAM, ethnic diversity and pregnant women.

关键词： Pregnancy Complementary medicine Traditional medicine Alternative medicine

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Performance and ruminal parameters of fattening Moghani lambs fed recycled poultry bedding

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Animal Nutrition 2017年第2期3卷 145-150页

作者： Ayoub Azizi Afrooz sharifi Arash Azarfar Ali Kiani alireza Jolazadeh Animal Science Group Faculty of Agricultural SciencesLorestan University Animal Science Department Khuzestan Ramin Agricultural and Natural Resources University

This study investigated the effects of recycled poultry bedding(RPB) on performance and protozoa population, microbial enzyme activity and microbial protein synthesis(MPS) in rumen contents of fattening lambs. Thirty-six male Moghani lambs(31.4 ± 3.2 kg body weight) were fed iso-energetic and iso-nitrogenous diets containing 0, 70,140 or 210 g/kg dry matter(DM) RPB in a balanced randomized design(9 lambs per treatment). Results showed that final body weight, DM intake, average daily gain and feed conversion ratio were unchanged(P > 0.05) by RPB inclusion. Total protozoa population and subfamily of Entoniniinae and Diplodiniiae were linearly decreased by RPB(L, P 0.05) by feeding the experimental diets. Inclusion of RPB in the diet linearly decreased extra cellular and total a-amylase activity(L, P 0.05). The extra cellular activity of proteases tended to increase(L, P=0.07) and their total and cellular activity increased(P > 0.05) in lambs fed RPB. Incorporation of RPB into the diet had no effect(L, P > 0.05) on urinary purine derivative excretion and MPS. In conclusion, inclusion of RPB up to 210 g/kg DM had no negative impact on performance, ruminal fibrolytic enzyme activity and MPS, while it increased rumen protease activity and decreased protozoa population in fattening Moghani lambs.

关键词： Recycled poultry bedding Performance Enzyme activity Microbial protein Lamb

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Ectoparasites of lesser mouse eared bat,Myotis blythii from Kermanshah Iran

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Asian Pacific Journal of Tropical Medicine 2010年第5期3卷 371-373页

作者： Vatandoost Hassan Telmadarraiy Zakkyeh sharifi Mozafar Moradi alireza Kamali Maryam Taran Mojtaba School of Public Health Tehran University of Medical SciencesP.O.Box:6446-14155TehranIran Biology Department Environment Research CenterKermanshah University of RaziKermanshahIran

Objective:To identify the ectoparasits of lesser mouse eared bat,Myotis blythii inside the MahiDasth cave in Kermanshah province,***:A total of 30 lasser mouse eared bat(Myotis blythii) in a cave close to Kermanshah city were hunted with special net and were transported to the *** anesthetizing by chloroform,ectoparasites from these bats were removed and ***:The ectoparasites include flies,ticks and *** 39 identified flies belonged to two families including Strebilidae(7.7%) and Nyctmbiidae(92.3%).A total number of 5 ticks of larval,nymphal and adult stages of Ixodes vespertilionis and 18 mites from Spiturnicidae family were ***:The result of this study is a clue for the identification of ectoparasites from bats and implication of possible prevention measures for diseases transmitted by ectoparasites.

关键词： Myotis blythii Bat flies ectoparasites Iran

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Evaluation of the remaining lateral torsional buckling capacity in corroded steel members

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第11期11卷 887-897页

作者： Yasser sharifi Reza RAHGOZAR Department of Civil Engineering Kerman University

Corrosion is one of the main causes of deterioration in steel structures. Loss of thickness in flanges and web of corroded steel beams leads to reduction in section properties which can reduce the lateral torsional buckling capacity of the member. In this paper, thickness loss data were compiled from four samples of corrosion damaged I-beams removed from a petro-chemical plant. Visual examination of the four corroded beams showed that they were corroded uniformly. To improve the accuracy of the results, a large number of measurements for surface roughness were taken for each beam, totally 770 values to obtain the average thickness of flanges and web of each beam. The data was used to develop a corrosion decay model in order to calculate the percentage remaining lateral torsional buckling capacity of long and short span beams which are laterally unrestrained. To estimate the percentage of remaining lateral torsional buckling capacity in the corroded damaged I-beams, the readily available minimum curves for different types of universal beams in conjunction with information on the thickness loss were used. The results can be used by practicing engineers for better estimation on the service life of deteriorated steel structures.

关键词： Corrosion Steel structures Lateral torsional buckling Beams

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Stabilizing silica nanoparticles in high saline water by using polyvinylpyrrolidone for reduction of asphaltene precipitation damage under dynamic condition

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Chinese Journal of Chemical Engineering 2019年第5期27卷 1021-1029页

作者： Mohammad Reza Aghajanzadeh Mohammad sharifi Department of Petroleum Engineering Amirkabir University of Technology

In this study, the performance of stable nanofluid containing SiO2 nanoparticles dispersed and stabilized in high salinity brine for asphaltene inhibition in dynamic condition is evaluated. In the first stage of this work, the stability of silica nanoparticles in different range of water salinity(0–100000 mg·L-1) is investigated. Next, stable nanofluid containing highest salinity is selected as asphaltene inhibitor agent to inject into the damaged core sample. The estimated values of oil recovery for base case, after damage process and after inhibition of asphaltene precipitation using nanofluid are 51.6%, 36.1% and 46.7%, respectively. The results showed the reduction in core damage after using nanofluid. In addition, the relative permeability curves are plotted for the base case, after damage process and also after inhibition of asphaltene precipitation using nanofluid. Comparison of relative permeability curves shows, relative permeability of oil phase decreased after damage process as compared with the base case. But after using nanofluid the oil relative permeability curve has shifted to the right and effective permeability of oil phase has been improved.

关键词： Formation damage Enhanced oil recovery Salinity Asphaltene Core flooding Nano particles

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Airborne GNSS-Receiver Threat Detection in No-Fading Environments

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Journal of Beijing Institute of Technology 2022年第6期31卷 613-620页

作者： Omid sharifi-Tehrani Department of Electrical and Communication Engineering Imam Hussein Comprehensive UniversityTehranIran.

Jamming and spoofing detection of global navigation satellite systems(GNSS)is of great *** and military aerial platforms use GNSS as main navigation systems and these systems are main target of threat *** this paper a simple method based on different empirical probability density functions of successive received signal powers and goodness of fit tech-nique is proposed for airborne platforms such as unmanned aerial vehicle(UAV),in no fading *** two different paths between UAV-satellite and UAV-threat,experience different empirical probability density functions which can be used to distinguish between authentic and threat *** results including detection and false alarm probabilities show good perfor-mance of proposed method as well as low computational burden.

关键词： detection global navigation satellite systems(GNSS) jamming spoofing unmanned aerial vehicle

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New dynamic permeability upscaling method for flow simulation under depletion drive and no-crossflow conditions

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Petroleum Science 2013年第2期10卷 233-241页

作者： Mohammad sharifi Mohan Kelkar McDougall School of Petroleum Engineering The University of Tulsa800 South Tucker DriveTulsaOklahoma74104United States

The main purpose of upscaling in reservoir simulation is to capture the dynamic behavior of fine scale models at the coarse scale. Traditional static or dynamic methods use assumptions about the boundary conditions to determine the upscaled properties, in this paper, we show that the upscaled properties are strongly dependent on the flow process observed at the fine scale. We use a simple no- crossflow depletion drive process and demonstrate that an upscaled property is not a constant value. Instead, if the goal is to match the performance of the fine scale model, the upscaled permeability changes with time. We provide an analytical solution to determine the upscaled permeability and present the value of upscaled permeability under limiting conditions. Our equation suggests that it is possible that upscaled value can fall outside the range of fine scale values under certain conditions. We show that for pseudo steady state flow, using common averaging methods like arithmetic or even geometric averaging methods can lead to optimistic results. We also show that the no-crossflow solution is significantly different than crossflow solution at late times. We validate our method by comparing the results of the method with flow simulation results in two and multi-layered models.

关键词： Upscaling permeability reservoir simulation no-crossflow depletion drive

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Cloud service selection using cloud service brokers: approaches and challenges

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Frontiers of Computer Science 2019年第3期13卷 599-617页

作者： Meysam VAKILI Neda JAHANGIRI Mohsen sharifi Department of Computer Engineering University of Science and Culture Tehran 14619-68151 Iran School of Computer Engineering Iran University of Science and Technology Tehran 16846-13114 Iran

Cloud computing users are faced with a wide variety of services to choose from. Consequently, a number of cloud service brokers (CSBs) have emerged to help users in their service selection process. This paper reviews the recent approaches that have been introduced and used for cloud service brokerage and discusses their challenges accordingly. We propose a set of attributes for a CSB to be considered effective. DifFerent CSBs' approaches are classified as either single service or multiple service models. The CSBs are then assessed, analyzed, and compared with respect to the proposed set of attributes. Based on our studies, CSBs with multiple service models that support more of the proposed effective CSB attributes have wider application in cloud computing environments.

关键词： cloud service broker (CSB) cloud service selection cloud computing quality of service (QoS)

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