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Monitoring rapid urban expansion using a multi-temporal RGB-impervious surface model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第2期13卷 146-158页

作者： amirreza shahtahmassebi Zhou-lu YU Ke WANG Hong-wei XU Jin-song DENG Jia-dan LI Rui-sen LUO Jing WU Nathan MOORE Institute of Agriculture Remote Sensing and Information Technology Zhejiang UniversityHangzhou 310029China Department of Geography Michigan State UniversityM148823USA

In this paper, we developed a novel method of combining remote sensing tools at the sub-pixel level for accurate identification of impervious surface time series changes. We examined the use of the red-green-blue impervious surface model (RGB-IS) in detecting time series internal modification of urban regions by integrating Landsat data collected over four different periods between 1987 and 2009 (i.e., 1987, 2000, 2002, and 2009). The performance of this approach was compared with two conventional methods, namely standard RGB-normalized difference vegetation index (NDVI) and post-classification technique. In contrast to conventional techniques, RGB-IS could monitor between-class changes, within-class changes, and location of these modifications. The proposed method was independent of seasonal changes and was also able to serve as a useful alternative for quick mapping growth hotspots and updating transportation corridor map. The results also showed that Cixi County, Zhejiang Province, China experienced tremendous impervious surface changes, especially along the corridors of newly constructed highways and around urban areas over the past 22 years.

关键词： Red-green-blue impervious surface model (RGB-IS). Multi-temnoral. Imnervious surface. Landsat

A model of flow separation controlled by dielectric barrier discharge

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Chinese Journal of Aeronautics 2017年第5期30卷 1660-1669页

作者： Mohammadreza BARZEGARAN amirreza KOSARI Faculty of New Science and Technologies University of Tehran Tehran *** Iran

Flow separation, as an aerodynamic phenomenon, occurs in specific conditions. The conditions are studied in a wind tunnel on different airfoils. The phenomenon can be delayed or suppressed by exerting an external momentum to the flow. Dielectric barrier discharge actuators arranged in a row of 8 and perpendicular to the flow direction can delay flow separation by exerting the momentum. In this study, a mathematical model is developed to predict a parameter, which is utilized to represent flow separation on an NACA0012 airfoil. The model is based on the neurofuzzy method applied to experimental datasets. The neuro model is trained in different flow conditions and the parameter is measured by pressure sensors.

关键词： Dielectric barrier discharge Flow separation Mathematical model NACA0012 airfoil Neuro-fuzzy

Natural coupled orbit-attitude periodic motions in the perturbed-CRTBP including radiated primary and oblate secondary

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Astrodynamics 2023年第2期7卷 229-249页

作者： Majid Bakhtiari Ehsan Abbasali Siavash Sabzy amirreza Kosari School of Advanced Technologies Iran University of Science and TechnologyNarmakTehran 16844Iran Aerospace Group Faculty of New Sciences and TechnologiesUniversity of TehranNorth Kargar StreetTehranIran

This study investigated periodic coupled orbit-attitude motions within the perturbed circular restricted three-body problem(P-CRTBP)concerning the perturbations of a radiated massive primary and an oblate *** radiated massive primary was the Sun,and each planet in the solar system could be considered an oblate *** the problem has no closed-form solution,numerical methods were ***,the general response of the problem could be non-periodic or periodic,which is significantly depended on the initial conditions of the orbit-attitude ***,the simultaneous orbit and attitude initial states correction(SOAISC)algorithm was introduced to achieve precise initial *** the other side,the conventional initial guess vector was essential as the input of the correction algorithm and increased the probability of reaching more precise initial ***,a new practical approach was developed in the form of an orbital correction algorithm to obtain the initial conditions for the periodic orbit of the *** new proposed algorithm may be distinguished from previously presented orbital correction algorithms by its ability to propagate the P-CRTBP family orbits around the Lagrangian points using only one of the periodic orbits of the unperturbed CRTBP(U-CRTBP).In addition,the Poincarémap and Floquet theory search methods were used to recognize the various initial guesses for attitude *** of these search methods was able to identify different initial guesses for attitude ***,as a new innovation,these search methods were applied as a powerful tool to select the appropriate inertia ratio for a satellite to deliver periodic responses from the coupled *** the mentioned perturbations to the U-CRTBP could lead to the more accurate modeling of the examination environment and a better understanding of a spacecraft's natural motion.A comparison between the orbit-attitude natural motions in the

关键词： oblate and radiated primary perturbed periodic orbit-attitudebehavior periodic orbit three-body problem Lagrangian points

Conceptual Design Process for LEO Satellite Constellations Based on System Engineering Disciplines

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Computer Modeling in Engineering & Sciences 2022年第5期131卷 599-618页

作者： Ali Salehi Mahdi Fakoor amirreza Kosari Seyed Mohammad Navid Ghoreishi Faculty of New Sciences and Technologies University of TehranTehranIran

Satellite design process is an interdisciplinary subject in which the need for collaboration among various science and engineering disciplines is ***,finding an optimal process for conceptual design of a satellite,which can optimize time and cost,is still an important *** this paper,based on system engineering approach,an optimal design process is proposed for LEO satellite *** the proposed method,design process,design sequences,and data flow are *** this regard,the conceptual design process is divided into two levels of mission(or constellation)and system(or satellite)as well as 15 main activities based on the mission profile,previous experiences of the authors,and existing ***,the relationships between these activities have been determined by considering the importance of relationships according to their ***,these relations are optimized based on design structure matrix(DSM).By utilizing this approach,system design process of a telecommunication satellite constellation in LEO is formulated in conceptual design *** and capability of the proposed approach in optimal design process of the satellite constellation are investigated by comparing the outcome with existing results in the literature.

关键词： Satellite constellation system engineering design structure matrix conceptual design

Synthesis of amorphous manganese borohydride in the(NaBH_4–MnCl_2) system, its hydrogen generation properties and crystalline transformation during solvent extraction

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Journal of Energy Chemistry 2017年第1期26卷 24-34页

作者： Robert A.Varin Deepak K.Mattar amirreza Shirani Bidabadi Marek Polanski Department of Mechanical and Mechatronics Engineering and Waterloo Institute for Nanotechnology University of Waterloo Faculty of New Technologies and Chemistry Military University of Technology

The mixture of(2NaBH4+ MnCl2) was ball milled in a magneto-mill. No gas release was detected. The XRD patterns of the ball milled mixture exhibit only the Bragg diffraction peaks of the Na Cl-type salt which on the basis of the present X-ray diffraction results and the literature is likely to be a solid solution Na(Cl)x(BH4)(1-x), possessing a cubic Na Cl-type crystalline structure. No presence of any crystalline hydride was detected by powder X-ray diffraction which clearly shows that NaBH4in the initial mixture must have reacted with MnCl2forming a Na Cl-type by-product and another hydride that does not exhibit X-ray Bragg diffraction peaks. Mass spectrometry(MS) of gas released from the ball milled mixture during combined MS/thermogravimetric analysis(TGA)/differential scanning calorimetry(DSC) experiments, confirms mainly hydrogen(H2) with a small quantity of diborane gas, B2H6. The Fourier transform infra-red(FT-IR) spectrum of the ball milled(2NaBH4+ MnCl2) is quite similar to the FT-IR spectrum of crystalline manganese borohydride, c-Mn(BH4)2, synthesized by ball milling, which strongly suggests that the amorphous hydride mechano-chemically synthesized during ball milling could be an amorphous manganese borohydride. Remarkably, the process of solvent filtration and extraction at 42 °C, resulted in the transformation of mechano-chemically synthesized amorphous manganese borohydride to a nanostructured,crystalline, c-Mn(BH4)2hydride.

关键词： Ball milling Mechano-chemical activation synthesis Amorphous manganese borohydride Mn(BH4)2 Dehydrogenation behavior Solvent extraction Crystallization of manganese borohydride Mn(BH4)2

Incremental adaptation strategies for agricultural water management under water scarcity condition in Northeast Iran

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Regional Sustainability 2021年第3期2卷 224-238页

作者： Morteza SALMANI SABZEVAR amirreza REZAEI Bagher KHALEGHI Department of Agricultural Extension and Education College of Agricultural Economics and DevelopmentUniversity of TehranKaraj***Iran Department of Forestry and Forest Economics University of TehranKaraj***Iran

Population growth and climate changes as two synergistic phenomena have damaged water resources nationwide and *** water resources available for agriculture is one of the most critical limiting factors in food production enhancement in *** must tackle the challenge of supplying the increasing demands for food due to population *** this purpose,we must get acquainted with how farmers make decisions and their adaptations to water scarcity conditions by studying their adaptation *** this case,we can predict the farmers’behaviors by recognizing the optimal adaptation strategies under water scarcity *** study aims to provide a model to examine and analyze the farmers’behaviors in the realm of water scarcity and the contributing factors to it,facilitating a better understanding of the potential implications of such scarcity,introducing the adaptation changeability procedures for agricultural water management and assistance to farmers to adapt,and developing the actions for mitigating the vulnerability of agriculture sector in *** this study,175 farmers in Northeast Iran were interviewed to conduct an applied research by questionnaire *** research tool was a researcher-made questionnaire designed based on the theoretical literature and designed *** to the research,the model of incremental adaptation strategies could determine the effects of a set of psychological and socioeconomic factors and the formation of adaptation decisions in water resources management under water scarcity *** results indicated that the concern and attitude,farmers’knowledge and technical skill,self-efficiency and risk-taking level,social capital and information availability for farmers,and the internal norm are significantly and positively correlated in this *** results provide a proper understanding of farmers’sustainable decision-making and a perspective on contributing factors to the strategy framework and im

关键词： Agricultural water management Incremental adaptation strategies Water scarcity Climate change Northeast Iran

Effects of welding parameters and welding sequence on residual stress and distortion in Al6061-T6 aluminum alloy for T-shaped welded joint

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Transactions of Nonferrous Metals Society of China 2020年第1期30卷 76-89页

作者： amirreza KHOSHROYAN Armin Rahmati DARVAZI Department of Marine Technology Amirkabir University of TechnologyTehranIran Faculty of Technology and Engineering(East of Guilan) University of GuilanRudsarIran

The distribution of temperature and then the distribution of residual stress and distortion in the stiffened aluminum alloy Al6061-T6 plates under the metal inert gas(MIG)welding process were investigated by three dimensional thermo-mechanical coupled finite element model using Ansys *** properties of materials were considered temperature-dependent and the filler metal was added to the workpiece by the element birth and death *** three modes of current,two different speeds and two various sequences,the distribution of residual stress and distortion were calculated and *** results showed that increase in welding speed decreased the vertical deflection in the plate,transverse shrinkage and angular distortion of plate and the lateral deflection of stiffener,but increased the maximum longitudinal tensile stress in the plate and ***,increase in current increased the residual stress and deformation in the plate and stiffener,and the change in the welding sequence changed the distribution of the distortion in the plate and the stiffener without significant change in the distribution of the longitudinal residual stress.

关键词： welding parameters welding sequence residual stress distortion

Comparison of Immune Responses against FMD by a DNA Vaccine Encoding the FMDV/O/IRN/2007 VP1 Gene and the Conventional Inactivated Vaccine in an Animal Model

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Virologica Sinica 2012年第5期27卷 286-291页

作者： Farahnaz Motamedi Sedeh Hoorieh Soleimanjahi amirreza Jalilian Homayoon Mahravani Agricultural Medical and Industrial Research School Virology Department Faculty of Medical ScienceTarbiat Modares University RaziVaccine and Serum Research Institute

Foot-and-mouth disease virus （FMDV） is highly contagious and responsible for huge outbreaks among cloven hoofed animals. The aim of the present study is to evaluate a plasmid DNA immunization system that expresses the FMDV/OflRN/2007 VP1 gene and compare it with the conventional inactivated vaccine in an animal model. The VP1 gene was sub-cloned into the unique Kpn I and BamH I cloning sites of the peDNA3.1＋ and pEGFP-N1 vectors to construct the VPI gene cassettes. The transfected BHKT7 cells with sub-cloned pEGFP-N1-VP1 vector expressed GFP-VP1 fusion protein and displayed more green fluorescence spots than the transfected BHKT7 cells with pEGFP-N1 vector, which solely expressed the GFP protein. Six mice groups were respectively immunized by the sub-cloned pcDNA3.1＋-VP1 gene cassette as the DNA vaccine, DNA vaccine and PCMV-SPORT-GMCSF vector （as molecular adjuvant） together, conventional vaccine, PBS （as negative control）, pcDNA3.1＋ vector （as control group） and PCMV-SPORT vector that contained the GMCSF gene （as control group）. Significant neutralizing antibody responses were induced in the mice which were immunized using plasmid vectors expressing the VP1 and GMCSF genes together, the DNA vaccine alone and the conventional inactivated vaccine （P〈0.05）. Co-administration of DNA vaccine and GMCSF gene improved neutralizing antibody response in comparison with administration of the DNA vaccine alone, but this response was the most for the conventional vaccine group. However, induction of humeral immunity response in the conventional vaccine group was more protective than for the DNA vaccine, but T-cell proliferation and IFN-？ concentration were the most in DNA vaccine with the GMCSF gene. Therefore the group that was vaccinated by DNA vaccine with the GMCSF gene, showed protective neutralizing antibody response and the most Thl cellular immunity.

关键词： DNA vaccine Foot-and-mouth disease virus Immune Response VP 1 gene

Evaluation of significant manufacturing parameters in lost foam casting of thin-wall Al-Si-Cu alloy using full factorial design of experiment

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Transactions of Nonferrous Metals Society of China 2013年第10期23卷 2843-2851页

作者： Hassan JAFARI Mohd Hsbullah IDRIS amirreza SHAYGANPOUR Department of Materials Manufacturing and Industrial Engineering Faculty of Mechanical Engineering Universiti Teknologi Malaysia Department of Materials Engineering Faculty of Mechanical Engineering Shahid Rajaee Teacher Training University

Controlling process parameters of lost foam casting （LFC） enables this process to produce defect-free complex shape castings. An experimental investigation on lost foam casting of an A1-Si-Cu cast alloy was carried out. The effects of pouting temperature, slurry viscosity, vibration time and sand size on surface finish, shrinkage porosity and eutectic silicon spacing of thin-wall casting were investigated. A full two-level factorial design of experimental technique was used to identify the significant manufacturing factors affecting the properties of casting. Pouring temperature was found as the most significant factor affecting A1-Si-Cu lost foam casting quality. It was shown that flask vibration time interacted with pouring temperature influenced euteetic silicon spacing and porosity percentage significantly. The results also revealed that the surface quality of the samples cast in fine sand moulds at higher pouring temperatures was almost unchanged, while those cast in coarse sand moulds possessed lower surface qualities. Furthermore, variation in slurry viscosity showed no significant effect on the evaluated properties compared to other parameters.

关键词： Al-Si-Cu alloy lost foam casting full factorial design surface finish porosity silicon spacing