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International Journal of Minerals,Metallurgy and Materials 2016年第7期23卷 799-809页

作者： ali Alavi Nia ali shirazi Department of Mechanical Engineering Bu-Ali Sina University

Friction stir welding is a new and innovative welding method used to fuse materials. In this welding method, the heat generated by friction and plastic flow causes significant changes in the microstructure of the material, which leads to local changes in the mechanical properties of the weld. In this study, the effects of various welding parameters such as the rotational and traverse speeds of the tool on the microstructural and mechanical properties of copper plates were investigated; additionally, Charpy tests were performed on copper plates for the first time. Also, the effect of the number of welding passes on the aforementioned properties has not been investigated in previous studies. The results indicated that better welds with superior properties are produced when less heat is transferred to the workpiece during the welding process. It was also found that although the properties of the stir zone improved with an increasing number of weld passes, the properties of its weakest zone, the heat-affected zone, deteriorated.

关键词： copper friction stir welding mechanical properties microstructure

Molecular dynamics investigation of mechanical properties of single-layer phagraphene

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 495-503页

作者： ali Hossein Nezhad shirazi Institute of Structural Mechanics Bauhaus-Universitat WeimarWeimarGermany

Phagraphene is a very attractive two-dimensional (2D) full carbon allotrope with very interesting mechanical, electronic, optical, and thermal properties. The objective of this study is to investigate the mechanical properties of this new graphene like 2D material. In this work, mechanical properties of phagraphene have been studied not only in the defect-free form, but also with the critical defect of line cracks, using the classical molecular dynamics simulations. Our study shows that the pristine phagraphene in zigzag direction experience a ductile behavior under uniaxial tensile loading and the nanosheet in this direction are less sensitive to temperature changes as compared to the armchair direction. We studied different crack lengths to explore the in fluence of defects on the mechanical properties of phagraphene. We also investigated the temperature effect on the mechanical properties of pristine and defective phagraphene. Our classical atomistic simulation results confirm that larger cracks can reduce the strength of the phagraphene. Moreover, it was shown the temperature has a considerable weakening effect on the tensile strength of phagraphene. The results of this study may be useful for the design of nano-devices using the phagraphene.

关键词： phaqraphene mechanical properties crack propagation molecular dynamics thermal effects

Mechanical responses of pristine and defective hexagonal boron-nitride nanosheets:A molecular dynamics investigation

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 623-631页

作者： Mohammad SALAVATI Arvin MOJAHEDIN ali Hossein Nezhad shirazi Institute of Structural Mechanics Bauhaus-Universitat WeimarWeimar D-99423Germany

ABSTRACT In this work we conducted classical molecular dynamics(MD)simulation to investigate the mechanical characteristics and failure mechanism of hexagonal boron-nitride(h-BN)*** and defective structure of h-BN nanosheets were considered under the uniaxial tensile loadings at various *** defective structure contains three types of the most common initial defects in engineering materials that are known as cracks,notches(with various length/size),and point vacancy defects(with a wide range of concentration).MD simulation results demonstrate a high load-bearing capacity of extremely defective(amorphized)h-BN *** results also reveal that the tensile strength decline by increasing the defect content and temperature as *** MD results provide a comprehensive and useful vision concerning the mechanical properties ofh-BN nanosheets with/without defects,which is very critical for the designing of nanodevices exploiting the exceptional physics of h-BN.

关键词： hexagonal boron-nitride mechanical properties crack notch point defects molecular dynamics

Analysis of socio-environmental impacts of the loss of urban trees and vegetation in Lahore,Pakistan:a review of public perception

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Ecological Processes 2016年第1期5卷 48-59页

作者： Safdar ali shirazi Jamil H.Kazmi Department of Geography University of the PunjabQuaid-i-Azam CampusLahorePakistan Department of Geography University of KarachiKarachiPakistan

Introduction:This paper focused on the process of urbanization in Lahore and its correlation with the loss of urban vegetation and perceived environmental impacts based on local population’s perception through administration of a questionnaire *** is known as a city of gardens and green spaces in Pakistan and always possessed rich green character in its long *** the past few decades due to rapid urbanization,the city has lost its aesthetically important urban vegetation,tress,and *** field studies and remote sensing data revealed that the loss of vegetation has been experienced at an astonishing rate in many union councils of the ***:This study was conceived to probe importance and value of the urban tress and vegetation of Lahore in an environmental context and its general importance for the residents of the *** objectives were to analyze the role of vegetation in the life of citizens;the specific objective was to reveal the attitudes and responses of city dwellers about loss of urban trees/vegetation and its role in the overall environment,process of urbanization,and maintenance *** the present paper,perception of local people(n=2080)regarding the socio-environmental impacts due to the ongoing process of urbanization and detriments of vegetation loss has been probed through administration of a household *** collected data has been tested with respondent’s age,gender,marital status,education,monthly income,and ***:This study was an attempt to document and explore the change in historical transformation in vegetation and perception of the sample population of *** perception survey has revealed that urbanization is the major cause of loss of vegetation and has caused a number of perceived environmental problems in the ***:The study underlined an analysis of people’s perceptions regarding the loss of trees and *** perceived socio-environmental findings revea

关键词： Anthropogenic Union council Socio-environmental Perception Vegetation Urban trees

Correction to: Analysis of socioenvironmental impacts of the loss of urban trees and vegetation in Lahore, Pakistan: a review of public perception

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Ecological Processes 2019年第1期8卷 342-343页

作者： Safdar ali shirazi Jamil H.Kazmi Department of Geography University of the PunjabQuaid-i-Azam CampusLahorePakistan Department of Geography University of KarachiKarachiPakistan.

Correction to:Ecol Process https://***/10.1186/s13717-016-0050-8 In the original publication of this article(shirazi et al.,2016)the author figured out that in the Fig.1,the upper left corner Map of Pakistan was inappropriate as per the national *** map of Pakistan,Jammu&Kashmir(occupied by India)must be shown annexed with Pakistan while mentioning Azad Jammu&Kashmir as disputed territory.

关键词： al. Pakistan occupied

Prediction of the burden of road traffic injuries in Iran by 2030: Prevalence, death,and disability-adjusted life years

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Chinese Journal of Traumatology 2024年第4期27卷 242-248页

作者： Mozhgan Seif Sedigheh Edalat ali Majidpour Azad shirazi Somayeh alipouri Mohsen Bayati Non-communicable Diseases Research Center Department of EpidemiologySchool of HealthShiraz University of Medical SciencesShirazIran Health Human Resources Research Center School of Health Management and Information SciencesShiraz University of Medical SciencesShirazIran Health Policy Research Center Institute of HealthShiraz University of Medical SciencesShirazIran

Purpose:Road traffic accidents pose a global challenge with substantial human and economic *** a high incidence of road traffic injuries,leading to a significant burden on *** studyaims to predict the future burden of road traffic injuries in Iran until 2030,providing valuable insights forpolicy-making and interventions to improve road safety and reduce the associated human and ***:This analytical study utilized time series models,specifically autoregressive integrated movingaverage(ARIMA)and artificial neural networks(ANNs),to predict the burden of road traffic accidents byanalyzing past data to identify patterns and trends in Iran until *** required data related toprevalence,death,and disability-adjusted life years(DALYs)rates were collected from the Institute forHealth Metrics and Evaluation database and analyzed using R software and relevant modeling andstatistical analysis ***:Both prediction models,ARIMA and ANNs indicate that the prevalence rates(per 100,000)of allroad traffic injuries,except for motorcyclist road injuries which have an almost flat trend,remaining ataround 430,increase by *** on estimations of both models,the rates of death and DALYs due tomotor vehicle and pedestrian road traffic injuries *** motor vehicle road injuries,estimatedtrends decrease to approximately 520 DALYs and 10 ***,for pedestrian road injuries these ratesreached approximately 300 DALYs and 6 deaths,according to the *** cyclists and other roadtraffic injuries,the predicted DALY rates by the ANN model increase to almost 50 and 8,while predictionsconducted by the ARIMA model show a static trend,remaining at 40 and approximately ***,these rates for the prediction of death rate by the ANN model increased to 0.6 and 0.1,while predictionsconducted by the ARIMA model show a static trend,remaining at 0.43 and *** to the ANNmodel,the predicted rates of DALY and death for m

关键词： Accidents Traffic Accident prevention Motorcycles Road injury Forecasting

Sensor Placement to Improve the Positioning Performance Based on Angle of Arrival (AOA)

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Wireless Engineering and Technology 2010年第1期1卷 41-45页

作者： Behzad Omidali S. S.ali-Asghar Beheshti shirazi 不详

In this paper, a method for sensor placement to improve the placement quality based on angle of arrival of signal in a specific area is proposed. The installation place of sensors may be constrained with specified boundaries. In this me-thod, the criterion of maximum quality of placement is the Cramer-Rao bound. The generalized pattern search as an effective method is used to maximize error bound of the placement problem by angle of arrival. Better results are ob-tained in comparison with results of genetic algorithm. The derived results are compared from two aspects of run time and result quality.

关键词： Sensor Placement Positioning Cramer-Rao Bound Numerical Optimization

Structure Stability and Oxygen Permeability of Perovskite-type Oxides of Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.1)R_(0.1)O_ (3-δ)(R=Al,Mn,Fe,Ce,Cr,Ni,Co)

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Journal of Materials Science & Technology 2012年第2期28卷 177-183页

作者： Ensieh Ganji Babakhani Jafar Towfighi Laleh shirazi ali Nakhaeipour Akbar Zamaniyan Zahra Shafiei Gas Department Research Institute of Petroleum Industry (RIPI) Chemical Engineering Department Engineering FacultyUniversity of Tarbiat Modares

Perovskite-type a0.5Sr0.5Co0.8Fe0.1R0.1O3-δ （R=Al, Mn, Fe, Ce, Cr, Ni, Co） oxide membranes were ex- ploited and synthesized. Oxygen behavior, order-disorder transition and phase stability of these composite oxides were investigated by combined analysis of X-ray diffraction （XRD）, temperature programmed desorp- tion （TPD）, thermogravimetric-differential thermal analysis （TG-DTA）. Oxygen permeation through these membranes was studied by the gas chromatography （GC） method using a high-temperature permeation cell in a wide temperature range from 700 to 950℃. High permeation fluxes were observed for these materials. The high permeation flux was about 3.19 ***-2 under air/He gradients at 950℃, which was achieved for a0.5Sr0.5Co0.8Fe0.1R0.1O3-δ（BSCFNiO） membrane. The results of analysis showed no phase transition for BSCFNiO oxide with increasing temperature and XRD pattern of this material after O2-TPD indicated to sustain a pure perovskite structure after oxygen permeation process.

关键词： Perovskite Ceramic membrane Oxygen separation Phase stability

Presenting a Meta Layer Model For Separation Of Crosscutting Concerns In Aspect Oriented Architecture

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Presenting a Meta Layer Model For Separation Of Crosscutting...

Effect of injection angle,density ratio,and viscosity on droplet formation in a microfluidic T-junction

2010 3rd IEEE International Conference on Computer Science and Information Technology—ICCSIT 2010

作者： ali Akbar Serafat Hoesin shirazi Payame Noor University Tehran Iran Zaeim Electronic Industries Maleke Ashtar University Tehran

there are some attributes in software architecture which can not be assigned to a specific component or layer. So one of the main concerns in architectural designing is making use of these attributes. It is tried to separate these cross cutting concerns from software architecture by presenting a model in this *** this model not only the cross cutting concerns are separated from the architecture, but also these attributes are divided into two categories as: functional and none functional each of which placed in different layers. Additionally, this model proposes a method for expressing crosscutting concerns by extending the xADL 2.0 architecture describing language. One of the most important benefits of this method is that it doesn’t create any changes in main architecture.

关键词： software architecture aspect orientation cross cutting concerns architecture describing language.

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Theoretical & Applied Mechanics Letters 2017年第4期7卷 243-251页

作者： Mohammad Yaghoub Abdollahzadeh Jamalabadi Mohammadreza Daqiq shirazi ali Kosar Mostafa Safdari Shadloo Department of Mechanical Robotics and Energy Engineering Dongguk University Seou104620 Republic of Korea School of Mechanical Engineering College of Engineering University of Tehran Tehran Iran Mechatronics Engineering Program Faculty of Engineering and Natural Sciences Sabanci University Tuzla Istanbu134956 Turkey CORIA-UMR 6614 Normandie University CNRS-University and INSA of Rouen 76000 Rouen France

The T-junction microchannel device makes available a sharp edge to form micro-droplets from biomaterial solutions. This article investigates the effects of injection angle, flow rate ratio, density ratio,viscosity ratio, contact angle, and slip length in the process of formation of uniform droplets in microfluidic T-junctions. The governing equations were solved by the commercial software. The results show that contact angle, slip length, and injection angles near the perpendicular and parallel conditions have an increasing effect on the diameter of generated droplets, while flow rate, density and viscosity ratios, and other injection angles had a decreasing effect on the diameter.

关键词： Microfluidics Droplet formation Flow rate ratio Density ratio