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Drivers of Forecasting the Behavioral Intention and Acceptance Behavior of the Hail Canon Technology(HCT): Using Logistic and System Dynamics Modeling

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Chinese Geographical Science 2023年第3期33卷 549-564页

作者： ABADI Bijan HAGHANINIA mohammad Faculty of Agriculture University of MaraghehGolshahr Town 55181-83111Iran

Globally known about the drivers through which farmers are instigated to uphold and use Hail Canon Technology(HCT)is ***,this article intended to examine the drivers of forecasting the behavioral intention and acceptance behavior of the HCT,249 apple farmers from northwestern Iran were recruited,including adopters(n1=114)and non-adopters(n2=135).The conceptual foundation included demographic theory,resource-based theory,theory of planned behavior,innovation diffusion model,and institutional support *** also used the system dynamics model(SDM)in the Netlogo to assess the results of the conventional statistical approach(i.e.,the logistic model).Authenticated the fitness of conceptual model with the data,logistic model manifests that the most outstanding determinants of the acceptance of HCT entail age,experience,total land size,income,attitude,compatibility,visibility,relative advantage,and financial *** the SDM,it was also shown that the results of the logistic model are confirmed by the *** conclusion,management implications are available for the university extension to eliminate the adoption obstacles and stir up farmers to join in applying HCT,furthermore,researchers would avail themselves of remarks for future research.

关键词： Canon visibility furthermore

On Time-Constant Robust Tuning of Fractional Order [Proportional Derivative] Controllers

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IEEE/CAA Journal of Automatica Sinica 2019年第5期6卷 1179-1186页

作者： Vahid Badri mohammad Saleh Tavazoei Electrical Engineering Department Sharif University of TechnologyTehranIran

This paper deals with analyzing a newly introduced method for tuning of fractional order [proportional derivative](FO[PD]) controllers to be used in motion control. By using this tuning method, not only the phase margin and gain crossover frequency are adjustable, but also robustness to variations in the plant time-constant is guaranteed. Conditions on the values of control specifications(desired phase margin and gain crossover frequency) for solution existence in this tuning method are found. Also, the number of solutions is analytically determined in this study. Moreover, experimental verifications are presented to indicate the applicability of the obtained results.

关键词： Fractional order controller robustness solution existence tuning method

Digital mapping of soil physical and mechanical properties using machine learning at the watershed scale

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Journal of Mountain Science 2023年第10期20卷 2975-2992页

作者： mohammad Sajjad GHAVAMI Shamsollah AYOUBI mohammad Reza MOSADDEGHI Salman Naimi Department of Soil Science College of AgricultureIsfahan University of TechnologyIsfahan ***Iran

Knowledge about the spatial distribution of the soil physical and mechanical properties is crucial for soil management,water yield,and sustainability at the watershed scale;however,the lack of soil data hinders the application of this tool,thus urging the need to estimate soil properties and consequently,to perform the spatial *** research attempted to examine the proficiency of three machine learning methods(RF:Random Forest;Cubist:Regression Tree;and SVM:Support Vector Machine)to predict soil physical and mechanical properties,saturated hydraulic conductivity(Ks),Cohesion measured by fall-cone at the saturated(Psat)and dry(Pdry)states,hardness index(HI)and dry shear strength(SS)by integrating environmental variables and soil features in the Zayandeh-Rood dam watershed,central *** determine the best combination of input variables,three scenarios were examined as follows:scenarioⅠ,terrain attributes derivative from a digital elevation model(DEM)+remotely sensed data;scenarioⅡ,covariates of scenarioⅠ+selected climatic data and some thematic maps;scenarioⅢ,covariates in scenarioⅡ+intrinsic soil properties(Clay,Silt,Sand,bulk density(BD),soil organic matter(SOM),calcium carbonate equivalent(CCE),mean weight diameter(MWD)and geometric weight diameter(GWD)).The results showed that for Ks,Psat Pdry and SS,the best performance was found by the RF model in the third scenario,with R2=0.53,0.32,0.31 and 0.41,respectively,while for soil hardness index(HI),Cubist model in the third scenario with R2=0.25 showed the highest *** predicting Ks and Psat,soil characteristics(*** and soil SOM and BD),and land use were the most important *** predicting Pdry,HI,and SS,some topographical characteristics(Valley depth,catchment area,mltiresolution of ridge top flatness index),and some soil characteristics(***,SOM and MWD)were the most important input *** results of this research present moderate accuracy,however,the methodology em

关键词： Machine learning Soil physical property Soilmechanical property Saturatedhydraulic conductivity Soil cohesion Soil shear strength.

EFFECTS OF REACTION AND PROCESSING PARAMETERS ON ETHYLENE POLYMERIZATION USING DIFFERENT ZIEGLER-NATTA CATALYSTS:EMPLOYMENT OF TAGUCHI EXPERIMENTAL DESIGN AND RESPONSE SURFACE METHOD

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Chinese Journal of Polymer Science 2007年第2期25卷 153-162页

作者： mohammad Najafi Vahid Haddadi-Asl Polymer Engineering Department Amirkabir University of TechnologyP.O.Box 15875-4413TehranIran

Different Ziegler-Natta catalysts were employed to polymerize ethylene. To investigate the influences of reaction parameters, namely Al/Ti molar ratio, hydrogen and processing parameters, i.e. ethylene pressure and temperature, a Taguchi experimental design was worked out. An L27 orthogonal array was chosen to take the above-mentioned parameters and relevant interactions into account. Response surface method was the tool used to analyze the experimental design results. Al/Ti, ethylene pressure and temperature were selected as experimental design factors, and catalyst activity and polymerization yield were the response parameters. Increasing pressure, due to an increment in monomer accessibility, and rising Al/Ti, because of higher reduction in the catalysts, cause an increase in both polymerization yield and catalyst activity. Nonetheless, a higher temperature, thanks to reducing ethylene solubility in the slurry medium and partially catalyst destruction, lead to a reduction in both response parameters. A synergistic effect was also observed between temperature and pressure. All catalyst activities will reduce in the presence of hydrogen. Molecular weight also shows a decline in the presence of hydrogen as a transfer agent. However, the polydispersity index remains approximately intact. Using SEM, various morphologies, owing to different catalyst morphologies, were seen for the polyethylene.

关键词： L27 Taguchi experimental design Response surface method Polyethylene polymerization Ziegler-Natta catalysts.

Performance improvement of complementary feeders using static transfer switch system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 189-200页

作者： Tahir MAHMOOD mohammad Ahmad CHOUDHRY Department of Electrical Engineering University of Engineering and Technology

The performance of complementary feeders, running in parallel, can be significantly improved by installing static transfer switches （STSs） at critical locations. We develop the STS control logic, which transfers the critical load from the preferred feeder to the alternate feeder when a voltage sag or a fault occurs on the preferred feeder. A forced commutation technique is proposed and implemented to turn off the preferred feeders＇ thyristor, thus avoiding cross current to flow and minimizing the transfer time. Simulation results show that the forced commutation technique is more effective as compared to the recently proposed time delay technique for STS operation. Two different feeders, namely New Exchange, the preferred feeder, and Sector 1-10/2, the alternate feeder of Islamabad Electric Supply COmpany （IESCO）, Pakistan, have been selected for case studies. The software PSCAD/EMTDC professional package has been used for simulation.

关键词： Complementary feeder Cross current Static transfer switch (STS) Sensitive load Voltage sag PSCAD/EMTDC

An efficient aerodynamic shape optimization of blended wing body UAV using multi-fidelity models

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Chinese Journal of Aeronautics 2018年第6期31卷 1165-1180页

作者： Parviz mohammad ZADEH Mohsen SAYADI Faculty of New Sciences and Technologies University of Tehran

This paper presents a novel optimization technique for an efficient multi-fidelity model building approach to reduce computational costs for handling aerodynamic shape optimization based on high-fidelity simulation models. The wing aerodynamic shape optimization problem is solved by dividing optimization into three steps—modeling 3D（high-fidelity） and 2D（lowfidelity） models, building global meta-models from prominent instead of all variables, and determining robust optimizing shape associated with tuning local meta-models. The adaptive robust design optimization aims to modify the shape optimization process. The sufficient infilling strategy—known as adaptive uniform infilling strategy—determines search space dimensions based on the last optimization results or initial point. Following this, 3D model simulations are used to tune local meta-models. Finally, the global optimization gradient-based method—Adaptive Filter Sequential Quadratic Programing（AFSQP） is utilized to search the neighborhood for a probable optimum point. The effectiveness of the proposed method is investigated by applying it, along with conventional optimization approach-based meta-models, to a Blended Wing Body（BWB） Unmanned Aerial Vehicle（UAV）. The drag coefficient is defined as the objective function, which is subjected to minimum lift coefficient bounds and stability constraints. The simulation results indicate improvement in meta-model accuracy and reduction in computational time of the method introduced in this paper.

关键词： Adaptive filter sequential quadratic programing(AFSQP) Adaptive robust meta-model Aerodynamic shape optimization Blended wing body(BWB) Move limit strategy Unmanned aerial vehicle(UAV)

Extended consecutive modal pushover procedure for estimating seismic responses of one-way asymmetric plan tall buildings considering soil-structure interaction

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Earthquake Engineering and Engineering Vibration 2014年第3期13卷 487-507页

作者： mohammad Hadikhan Tehrani Faramarz Khoshnoudian Department of Civil and Environmental Engineering Amirkabir University of Technology (Tehran Polytechnic)

Performance based design becomes an effective method for estimating seismic demands of buildings. In asymmetric plan tall building the effects of higher modes and torsion are crucial. The consecutive modal pushover （CMP） procedure is one of the procedures that consider these effects. Also in previous studies the influence of soil-structure interaction （SSI） in pushover analysis is ignored. In this paper the CMP procedure is modified for one-way asymmetric plan mid and high-rise buildings considering $SI. The extended CMP （ECMP） procedure is proposed in order to overcome some limitations of the CMP procedure. In this regard, 10, 15 and 20 story buildings with asymmetric plan are studied considering SSI assuming three different soil conditions. Using nonlinear response history analysis under a set of bidirectional ground motion; the exact responses of these buildings are calculated. Then the ECMP procedure is evaluated by comparing the results of this procedure with nonlinear time history results as an exact solution as well as the modal pushover analysis procedure and FEMA 356 load patterns. The results demonstrate the accuracy of the ECMP procedure.

关键词： consecutive modal pushover procedure soil-structure interaction bidirectional ground motion tall buildings seismic demands engineering demand parameters

Locational marginal price share: a new structural market power index

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Journal of Modern Power Systems and Clean Energy 2019年第6期7卷 1709-1720页

作者： mohammad Ebrahim HAJIABADI Mahdi SAMADI Department of Electrical and Computer Engineering Hakim Sabzevari UniversitySabzevarIran

Market power is known as the ability of units and generation companies(GenCos)to change electricity price *** cleared in the definition,locational marginal price(LMP)is the most important key in market power ***,the main objective of the paper is to analyze market power of units and GenCos based on their abilities to change electricity *** the first step,using Karush-Kuhn-Tucker(KKT)conditions of Lagrangian method,LMP is decomposed into four main *** components indicate the share of each unit at the LMP of each *** values are calculated by the proposed analytical method,and cannot be obtained using simulation *** the second step,"unit-based LMP share(LMP_S)"index,which indicates the contribution factor of each unit at LMP of each bus,is proposed as a new structural market power *** index is also used as an effective tool to determine the most profitable coalition between two *** that,the market operator can predict highly potential ***,"GenCosbased LMP_S"index is *** this effective tool,the contribution of each GenCo,which owns multiple units at various buses,at the LMP of each bus is *** proposed market power indices are calculated on the IEEE24-bus test system and compared with some conventional structural market power *** profits of units due to change of unit’s strategies verify the accuracy of the proposed method.

关键词： Lagrange relaxation method Locational marginal price(LMP)share Market power Coalition

MICELLIZATION STUDIES OF DODECYL BENZENESULFONIC ACID AND ITS INTERACTION WITH POLYVINYLPYRROLIDONE

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Chinese Journal of Polymer Science 2005年第1期23卷 29-35页

作者： mohammad Saleem Khan Zarshad Ali National Centre of Excellence in Physical Chemistry University of PeshawarPeshawar 25120PakistanNational Centre of Excellence in Physical ChemistryUniversity of PeshawarPeshawar 25120Pakistan

Dodecyl benzenesulfonic acid(DBSA)surfactant was used in the present study to find the effect of concentrationon its electrical conductance in solution from 293-323 K above and below the critical micelle concentration(CMC).Themicellization parameters *** of counter ion binding(β),aggregation number(n)and number of counter ion micelle(m)were *** interaction of DBSA with polyvinylpyrrolidone(PVP)was also studied at 293 K throughconductance and surface tension measure ments.A number of important parameters *** aggregation concentration(CAC),Gibb's free energy(△G)and binding ratio(R)were determined and the effect of NaCl on the CAC and polymersaturation point(PSP)was also investigated.

关键词： Micellization PVP Interaction Dodecyl benzene sulfonic acid(DBSA).