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Chinese Journal of Aeronautics 2016年第4期29卷 934-944页

作者： Hassan Pahange Mohammad hossein Abolbashari Department of Mechanical Engineering Ferdowsi University of Mashhad Department of Mechanical Engineering Lean Production Engineering Research Center Ferdowsi University of Mashhad

Collisions between birds and aircraft are one of the most dangerous threats to flight safety. In this study, smoothed particles hydrodynamics(SPH) method is used for simulating the bird strike to an airplane wing leading edge structure. In order to verify the model, first, experiment of bird strike to a flat aluminum plate is simulated, and then bird impact on an airplane wing leading edge structure is investigated. After that, considering dimensions of wing internal structural components like ribs, skin and spar as design variables, we try to minimize structural mass and wing skin deformation simultaneously. To do this, bird strike simulations to 18 different wing structures are made based on Taguchi’s L18 factorial design of experiment. Then grey relational analysis is used to minimize structural mass and wing skin deformation due to the bird strike. The analysis of variance(ANOVA) is also applied and it is concluded that the most significant parameter for the performance of wing structure against impact is the skin thickness. Finally, a validation simulation is conducted under the optimal condition to show the improvement of performance of the wing structure.

关键词： Bird strike Grey relational analysis Multi-objective optimization Smooth particle hydrody namics(SPH) Wing leading edge structure

A blockchain maturity model in agricultural supply chain

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Information Processing in Agriculture 2021年第3期8卷 398-408页

作者： Mohammad hossein Ronaghi Department of Management Shiraz UniversityShirazIran

Blockchain technology is a disruptive technology that changes business and supply chain *** distributed software architecture and advanced computing,blockchain can change the way information is exchanged between actors in the *** technol-ogy provides a platform for solving the problem of tracking product information in supply chain ***,the present study aims to provide a model for evaluating the maturity of blockchain technology in the agricultural supply *** present research is applied that has been done in three *** the first phase,the dimensions of the blockchain are ranked by agricultural experts using the SWARA *** research experts are 13 faculty members of the department of agriculture active in the field of technology *** the second phase,a model is designed to evaluate blockchain maturity using each dimension of blockchain technology and maturity *** the third phase,the proposed model is tested using data collected by a questionnaire in the supply chain of a company active in the agriculture *** research findings show that smart contracts,Internet of Things(IoT),and transaction records are of the highest impor-tance among the blockchain ***,the supply chain under study is in a good condition in digital ***,the originality aspect of the research is that it determines the importance of blockchain dimensions in the field of agriculture and from an applied point of view,it introduces the maturity model of blockchain in supply chain management.

关键词： Blockchain Agricultural supply chain Maturity model SWARA

Enhanced microstructural and mechanical properties of Stellite/WC nanocomposite on Inconel 718 deposited through vibration-assisted laser cladding

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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 327-334页

作者： hossein hosseini-Tayeb Seyed Mahdi Rafiaei Daneshpajoohan Pishro Higher Education Institute IsfahanIran Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayeganIsfahanIran

Stellite-21/WC nanopowders were deposited on Inconel through vibration-assisted laser cladding with different laser *** and scanning electron microscopy,hardness measurements,and wear characterizations were employed to understand the microstructural and mechanical behaviors of the *** showed that varying the cooling rate exerted remarkable effects on the microstructure of the as-cladded ***,increasing the laser power from 150 W to 250 W increased the heat input and the *** was affected by the scanning rate and powder feeding rate at a high laser power of 250 *** WC nanoparticles were added as reinforcement,the dilution magnitude intensified while the hardness value increased from HV 350 to HV *** wear characterizations indicated that the composites containing 3 wt%WC nanoparticles possessed the highest wear resistance.

关键词： Stellite WC nanoparticles mechanical properties laser cladding

Theoretical study of failure in composite pressure vessels subjected to low-velocity impact and internal pressure

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Frontiers of Structural and Civil Engineering 2020年第6期14卷 1349-1358页

作者： Roham RAFIEE hossein RASHEDI Shiva REZAEE Composites Research Laboratory Faculty o f New Science&TechnologiesUniversity o f TehranTehran ***Iran

A theoretical solution is aimed to be developed in this research for predicting the failure in internally pressurized composite pressure vessels exposed to low-velocity *** in-plane and out-of-plane failure modes are taken into account simultaneously and thus all components of the stress and strain fields are *** this purpose,layer-wise theory is employed in a composite cylinder under internal pressure and low-velocity *** stress/strain components are fed into appropriate failure criteria for investigating the occurrence of *** case of experiencing any in-plane failure mode,the evolution of damage is modeled using progressive damage modeling in the context of continuum damage ***,mechanical properties of failed ply are degraded and stress analysis is performed on the updated status of the *** the event of delamination occurrence,the solution is *** obtained results are validated with available experimental observations in open *** is observed that the sequence of in-plane failure and delamination varies by increasing the impact energy.

关键词： composite pressure vessel low-velocity impact failure theoretical solution progressive damage modeling

Structural optimization of filament wound composite pipes

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Frontiers of Structural and Civil Engineering 2022年第8期16卷 1056-1069页

作者： Roham RAFIEE Reza SHAHZADI hossein SPERESP Faculty of New Science and Technologies University of TehranTehran ***Iran

An optimization procedure is developed for obtaining optimal structural design of filament wound composite pipes with minimum cost utilized in pressurized water and waste-water ***,the short-term and long-term design constraints dictated by international standards are ***,proper computational tools are developed for predicting the structural properties of the composite pipes based on the design architecture of *** developed computational tools are validated by relying on experimental ***,an integrated design-optimization process is developed to minimize the price as the main objective,taking into account design requirements and manufacturing limitations as the constraints and treating lay-up sequence,fiber volume fraction,winding angle,and the number of total layers as design *** developed method is implemented in various case studies,and the results are presented and discussed.

关键词： composite pipes optimization experimental validation computational modeling filament winding

Design of on-board calibration methods for a digital sun sensor based on Levenberg–Marquardt algorithm and Kalman filters

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Chinese Journal of Aeronautics 2020年第1期33卷 339-351页

作者： Ali RAHDAN hossein BOLANDI Mostafa ABEDI Department of Electrical Engineering Iran University of Science&TechnologyTehran ***Iran Department of Electrical Engineering Shahid Beheshti UniversityTehran ***Iran

Digital sun sensor is one of the most important sensors used in the Attitude Determination System(ADS)of the *** to the harsh environmental conditions that exist in the space,various distortions may occur in the sun sensor optical system that lead to the reduced accuracy of this ***,it is necessary to recalibrate the optical parameters of the aforementioned *** this purpose,first a novel attitude independent error model is proposed for the SS-411 sun sensor that includes the central point of the CCD array,installation error,filter thickness and sensor ***,the mutual interfaces between the sensor parameters are considered in the developed *** order to extract the sensor parameters,a nonlinear optimization technique called the Levenberg–Marquardt is applied to the developed model as a batch *** addition,the Extended Kalman Filter(EKF)and the Unscented Kalman Filter(UKF)have been utilized as sequential *** will be shown that by considering a worst case of variation amount for sensor parameters,an accuracy improvement of about 17°is achieved by the developed calibration *** between the developed algorithms represents that UKF has higher accuracy,shorter time convergence but higher computational load.

关键词： Digital sun sensor Extended Kalman filter Levenberg–Marquardt On-board calibration Unscented Kalman filter

A New Evaluation Criterion for Optimizing the Mechanical Properties of Toughened Polypropylene/Silica Nanocomposites

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Chinese Journal of Polymer Science 2020年第8期38卷 877-887,I0008页

作者： hossein Pourrahmani Mona Golparvar Mohammad Fasihi Group of Energy Materials (E)cole Polytechnique Fédérale de LausanneSion 1951Switzerland School of Chemical Petroleum and Gas EngineeringIran University of Science and TechnologyTehran 16846-13114Iran School of Mechanical Engineering Braunschweig university of technologyBraunschweig 38106Germany

This study aims to experiment with the mechanical properties of polypropylene(PP)/thermoplastic elastomer/nano-silica/compatibilizer nanocomposite using the melt mixing *** addition of polyolefin elastomers has proved to be an approachable solution for low impact strength of PP,while it would also reduce the Young's modulus and tensile *** is why reinforcement would be applied to this combination to enhance the elastic *** mechanical properties of the prepared composites were devised to train an artificial neural network to predict these properties of the system in 6256 unknown ***,the sensitivity analysis was performed and the share of each input parameter on the respective output values was ***,a novel parameter called nanocomposite evaluation criterion(NEC)is introduced to analyze the suitability of the nanocomposites considering the mechanical ***,the formulation with optimal mechanical properties of toughness,elongation at break,tensile strength,Young's modulus,and impact strength was obtained.

关键词： Nanocomposite Polypropylene(PP) Silica Artificial neural networks Nanocomposite evaluation criterion(NEC) Sensitivity analysis

Dearomatization of normal paraffin by adsorption process using synthesized NaX zeolite

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Petroleum Science 2013年第3期10卷 408-414页

作者： hossein Faghihian Leila Riazi Department of Chemistry Shahreza Branch Islamic Azad University86145-311 Iran R&D Department I. C. I. I. C.Isfahan Iran

Linear alkyl benzenes （LABs） are the main materials for detergent production. The presence of aromatic compounds in this material can decrease the quality of the final product and enhance the deactivation rate of catalysts. In this research we used zeolite NaX for de-aromatization of the recycled paraffin from the alkylation unit of an LAB production complex. The effect of different parameters on the removal efficiency of adsorbent was studied and optimized. To study the re-usability of the adsorbent, the breakthrough curves were obtained by using a fixed bed column filled with the adsorbent. The results indicated that the adsorbent capacity remained unchanged after three regeneration cycles. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms. It was concluded that the Langmuir model agreed well with the experimental data. The calculated thermodynamic parameters of the adsorption showed that the adsorption process was spontaneous and exothermic. The reaction rate was estimated by the pseudo-second order kinetic model.

关键词： Dearomatization LAB zeolite adsorption separation

New insight into prediction of phase behavior of natural gas hydrate by different cubic equations of state coupled with various mixing rules

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Petroleum Science 2017年第4期14卷 780-790页

作者： Amir hossein Saeedi Dehaghani Deparlment of Petroleum Engineering Faculty of Chemical EngineeringTarbiat Modares UniversityTehranlran

Progress in hydrate thermodynamic study necessitates robust and fast models to be incorporated in reservoir simulation softwares. However, numerous models presented in the literature makes selection of the best,proper predictive model a cumbersome task. It is of industrial interest to make use of cubic equations of state(EOS) for modeling hydrate equilibria. In this regard, this study focuses on evaluation of three common EOSs including Peng–Robinson, Soave–Redlich–Kwong and Valderrama–Patel–Teja coupled with van der Waals and Platteeuw theory to predict hydrate P–T equilibrium of a real natural gas sample. Each EOS was accompanied with three mixing rules, including van der Waals(vd W),Avlonitis non-density dependent(ANDD) and general nonquadratic(GNQ). The prediction of cubic EOSs was in sufficient agreement with experimental data and with overall AARD% of less than unity. In addition, PR plus ANDD proved to be the most accurate model in this study for prediction of hydrate equilibria with AARD% of *** was observed that the accuracy of cubic EOSs studied in this paper depends on mixing rule coupled with them,especially at high-pressure conditions. Lastly, the present study does not include any adjustable parameter to be correlated with hydrate phase equilibrium data.

关键词： Gas Hydrate Cubic equation of state Mixing rule Thermodynamic modeling

Computational Study of Electromagnetic Fields,Eddy Currents and Induction Heating in Thin and Thick Workpieces

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Communications in Computational Physics 2010年第6期8卷 211-225页

作者： Mohammad hossein Tavakoli hossein Karbaschi Feridoun Samavat Physics Department Bu-Ali Sina UniversityHamedan 65174Iran

A set of 2D steady state finite element numerical simulations of electromagnetic fields,eddy currents distribution and induction heating pattern has been done for different thicknesses of a metal *** between the calculation results show the importance of workpiece thickness on induction heating process including electromagnetic field distribution,eddy currents pattern,heating structure and coil efficiency.

关键词： Computer simulation finite element analysis modeling induction heating metals