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Assessment of different topographic correction methods in ALOS AVNIR-2 data over a forest area

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International Journal of Digital Earth 2013年第5期6卷 504-520页

作者： Nafiseh Ghasemi Ali mohammadzadeh Mahmod Reza Sahebi Department of Photogrammetry&Remote Sensing Faculty of Geodesy and GeomaticsK.N.Toosi University of TechnologyTehranIran

Because the removal of topographic effects is one the most important preprocessing steps when extracting information from satellite images in digital Earth applications,the problem of differential terrain illumination on satellite imagery has been investigated for at least 20 *** there is no superior topographic correction method applicable to all areas and all images,a comparison of topographic normalization methods in different regions and images is *** this study,common topographic correction methods were applied on an ALOS AVNIR-2 image of a rugged forest area,and the results were evaluated through different *** results show that the simple correction methods[Cosine,Sun-Canopy-sensor(SCS),and Minnaert correction]are inefficient in exceptionally rough *** the improved correction methods(SCSC,modified Minnaert,and pixel-based Minnaert),the best result was achieved using a pixel-based Minnaert approach in which a separate correction factor in various slope angles is ***,this method should be considered for topographic correction,especially in forests with severe topography.

关键词： ALOS AVNIR-2 C Cosine digital earth forest Minnaert modified Minnaert pixel-based Minnaert SCS topographic correction

Estimation of flexible pavement structural capacity using machine learning techniques

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Frontiers of Structural and Civil Engineering 2020年第5期14卷 1083-1096页

作者： Nader KARBALLAEEZADEH Hosein GHASEMZADEH TEHRANI Danial mohammadzadeh SHADMEHRI Shahaboddin SHAMSHIRBAND Civil Engineering Department Shahrood University of TechnologyShahrood ***Iran Department of Civil Engineering Ferdowsi University of MashhadMashhad ***Iran Department of Elite Relations with Industries Khorasan Construction Engineering OrganizationMashhad ***Iran Department for Management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Information Technology Ton Duc Thang UniversityHo Chi Minh CityVietnam

The most common index for representing structural condition of the pavement is the structural *** current procedure for determining structural numbers involves utilizing falling weight deflectometer and ground-penetrating radar tests,recording pavement surface deflections,and analyzing recorded deflections by back-calculation *** procedure has two drawbacks:falling weight deflectometer and ground-penetrating radar are expensive tests;back-calculation ways has some inherent shortcomings compared to exact methods as they adopt a trial and error *** this study,three machine learning methods entitled Gaussian process regression,M5P model tree,and random forest used for the prediction of structural numbers in flexible *** of this paper is related to 759 flexible pavement sections at Semnan and Khuzestan provinces in Iran and includes“structural number”as output and“surface deflections and surface temperature”as *** accuracy of results was examined based on three criteria of R,MAE,and *** the methods employed in this paper,random forest is the most accurate as it yields the best values for above criteria(R=0.841,MAE=0.592,and RMSE=0.760).The proposed method does not require to use ground penetrating radar test,which in turn reduce costs and work *** machine learning methods instead of back-calculation improves the calculation process quality and accuracy.

关键词： transportation infrastructure flexible pavement structural number prediction Gaussian process regression M5P model tree random forest

Shear wall layout optimization of tall buildings using Quantum Charged System Search

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Frontiers of Structural and Civil Engineering 2020年第5期14卷 1131-1151页

作者： Siamak TALATAHARI mahdi RABIEI Department of Civil Engineering University of TabrizTabriz ***Iran Engineering Faculty Near East UniversityNicosia 99138Turkey

This paper presents a developed meta-heuristic algorithm to optimize the shear walls of tall reinforced concrete *** types of walls are considered as lateral resistant *** this paper,Quantum Charged System Search(QCSS)algorithm is presented as a new optimization method and used to improve the convergence capability of the original Charged System *** cost of tall building is taken as the objective *** the design of the lateral system plays a major role in the performance of the tall buildings,this paper proposes a unique computational technique that,unlike available works,focuses on structural efficiency or architectural *** technique considers both structural and architectural requirements such as minimum structural costs,torsional effects,flexural and shear resistance,lateral deflection,openings and *** robustness of the new algorithm is demonstrated by comparing the outcomes of the QCSS with those of its standard algorithm.

关键词： Quantum Charged System Search shear wall layout optimization tall buildings

Feasibility of crack free reinforced concrete bridge deck from materials composition perspective： a state of the art review

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Frontiers of Structural and Civil Engineering 2015年第1期9卷 91-103页

作者： mahdi AREZOUMANDI Department of Civil Architectural and Environmental Engineering Missouri University of Science and Technology 212 ButlerCarlton Hall 1401 N. Pine Street Rolla MO 65409 USA

Early age cracking on bridge deck has been the subject of many studies for years. Cracking is a major concern because it leads to premature deterioration of structures. Millions of dollars spent to repair the cracked bridge decks each year. To design an appropriate mixture for crack free bridge deck, it is important to study previous researches. This paper presents a comprehensive literature review of the performance of different materials compositions as well as methods have been used to reduce and control bridge deck cracks. Different material compositions and methods are discussed in terms of their performances as well as advantages and disadvantages.

关键词： bridge deck crack fiber shrinkage shrinkage reducing admixture

Agricultural experts’attitude towards precision agriculture:Evidence from Guilan Agricultural Organization,Northern Iran

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Information Processing in Agriculture 2016年第3期3卷 183-189页

作者： Mohammad Sadegh Allahyari Masoumeh mohammadzadeh Stefanos ANastis Department of Agricultural Management Rasht BranchIslamic Azad UniversityRashtIran Young Researchers and Elite Club Rasht BranchIslamic Azad UniversityRashtIran Department of Agricultural Economics Aristotle University of ThessalonikiGreece

Identifying factors that influence the attitudes of agricultural experts regarding precision agriculture plays an important role in developing,promoting and establishing precision *** aim of this study was to identify factors affecting the attitudes of agricultural experts regarding the implementation of precision agriculture.A descriptive research design was employed as the research method.A research-made questionnaire was used to examine the agricultural experts’attitude toward precision *** consistency was demonstrated with a coefficient alpha of 0.87,and the content and face validity of the instrument was confirmed by a panel of *** results show that technical,economic and accessibility factors accounted for 55%of the changes in attitudes towards precision *** findings revealed that there were no significant differences between participants in terms of gender,field of study,extension education,age,experience,organizational position and attitudes,while education levels had a significant effect on the respondent’s attitudes.

关键词： Attitudes Factor analysis Precision agriculture Experts’attitude

SYNTHESIS AND APPLICATIONS OF CROSS-LINKED POLY(DIALLYLDIMETHYL AMMONIUM CHLORIDE) AND ITS DERIVATIVE COPOLYMERS AS EFFICIENT PHASE TRANSFER CATALYST FOR NUCLEOPHILIC SUBSTITUTION REACTIONS

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Chinese Journal of Polymer Science 2011年第2期29卷 165-172页

作者： Hossein Mahdavi mahdi Mahmoudian School of Chemistry University College of ScienceUniversity of TehranTehranIran

Cross-linked poly（diallyldimethylammonium chloride） and its derivative copolymers were synthesized and used as phase transfer catalyst in the nucleophilic substitution reaction especially halogen exchange *** additi... 详细信息

关键词： Poly(diallyldimethylammonium chloride) Phase transfer catalyst Nucleophilic substitution reaction Halogen exchange reaction

Robust pre-specified time synchronization of chaotic systems by employing time-varying switching surfaces in the sliding mode control scheme

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Chinese Physics B 2016年第8期25卷 86-93页

作者： Alireza Khanzadeh mahdi Pourgholi Faculty of Electrical Engineering Shahid Beheshti University

In the conventional chaos synchronization methods, the time at which two chaotic systems are synchronized, is usually unknown and depends on initial conditions. In this work based on Lyapunov stability theory a sliding mode controller with time-varying switching surfaces is proposed to achieve chaos synchronization at a pre-specified time for the first time. The proposed controller is able to synchronize chaotic systems precisely at any time when we want. Moreover, by choosing the time-varying switching surfaces in a way that the reaching phase is eliminated, the synchronization becomes robust to uncertainties and exogenous disturbances. Simulation results are presented to show the effectiveness of the proposed method of stabilizing and synchronizing chaotic systems with complete robustness to uncertainty and disturbances exactly at a pre-specified time.

关键词： chaos synchronization finite time synchronization sliding mode controller time varying switching surfaces

Improvement of mechanical behavior of buried pipelines subjected to strike-slip faulting using textured pipeline

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Frontiers of Structural and Civil Engineering 2019年第5期13卷 1105-1119页

作者： mahdi IZADI Khosrow BARGI School of Civil Engineering College of EngineeringUniversity of TehranTehranIran

The present study investigates the mechanical behavior of a new generation of buried pipelines, dubbed the textured pipeline, which is subjected to strike-slip faulting. In conventional cylindrical pipelines, the axial and bending stresses brought about in their walls as a result of fault movement, lead to local buckling, which is construed as one of the major reasons contributing to pipeline failure. The present study has assessed 3-D numerical models of two kinds of buried textured pipelines, with 6 and 12 peripheral triangular facets, subjected to a strike-slip faulting normal to the axis of the pipelines, with and without internal pressure, with the two kinds of X65 and X80 steel, and with different diameter-to-thickness ratios. The results indicate that, because of specific geometry of this pipeline shell which is characterized by having lower axial stiffness and higher bending stiffness, compared to conventional cylindrical pipeline, they are considerably resistant to local (buckling. The results of this study can be conceived of as a first step toward comprehensive seismic studies on this generation of pipelines which aim at replacing the conventional cylindrical pipelines with textured ones in areas subjected to fault movement.

关键词： buried pipeline textured pipeline local buckling

Nonlinear Modeling and Analysis of a Novel Robot Fish with Compliant Fluidic Actuator as a Tail

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Journal of Bionic Engineering 2022年第3期19卷 629-642页

作者： Behzad Janizadeh Haji mahdi Bamdad School of Mechanical and Mechatronics Engineering Shahrood University of TechnologyShahrood***Iran

Compliant mobile robotics is a developing bioinspired concept of propulsion for *** paper studies the modeling and analysis of a compliant tail-propelled fish-like *** biomimetic design uses a fluid-filled network of channels embedded into the soft body to actuate the compliant tail and generate *** study analyzes the nonlinear dynamics of Fish Tail Fluidic Actuator(FTFA).The fluidic expansion under pressure creates a bending moment in the *** is demonstrated that the tail response follows the theoretical formulation extracted from the accurate *** this modeling,tail is assumed as a continuous Euler–Bernoulli beam considering large deflection and nonlinear ***,the implementation of Hamilton's principle and the method of calculation lead to the motion *** assumed mode method is used to achieve the mathematical model in the multi-mode system that is more similar to the soft continuous *** investigate the tendencies of the tail amplitude,swimming speed,and Strouhal number when the input driving frequency *** simulation results disclose that high swimming efficiency can be obtained at the multi-order resonances;meanwhile,the compliant fish robot is pushed at the corresponding frequency illustrating nonlinear behavior.

关键词： Compliant robotic fish Nonlinear continuous model Fluidic actuator Assume mode method Resonant effect