检索结果-南通市图书馆

Multidisciplinary design optimization of a dual-spin guided vehicle

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第7期37卷 133-148页

作者： Jalal Karimi mohammad Reza Rajabi Seyed hossein Sadati Seyed Mahid hosseini Department of Aerospace Engineering Malek Ashtar University of TechnologyTehranIran

In this research,a Multidisciplinary Design Optimization approach is proposed for the dual-spin guided flying projectile design considering external and internal parts of the body as design *** this way,a parametric formulation is *** related disciplines,including structure,aerodynamics,guidance,and control are *** total mass,maximum aerodynamic control effectiveness,minimum miss distance,maximum yield stress in all subsystems,controllability and gyroscopic stability constraints are some of objectives/constraints taken into *** problem is formulated in All-At-Ones Multidisciplinary Design Optimization approach structure and solved by Simulated Annealing and minimax *** optimal configurations are evaluated in various *** resulted optimal configurations have met all design objectives and constraints.

关键词： Flying projectile optimal design All-at-ones multidisciplinary optimization Structure discipline Guidance and control discipline Aerodynamic discipline

Analyzing the Interplay of Sintering Conditions on Microstructure and Hardness in Indirect Additive Manufacturing of 17-4PH Stainless Steel

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1611-1620页

作者： Erika Lannunziata mohammad hossein Mosallanejad Manuela Galati Gabriele Piscopo Abdollah Saboori Integrated Additive Manufacturing Center Department of Management and Production EngineeringPolitecnico di TorinoCorso Duca Degli Abruzzi 2410129TurinItaly

Indirect additive manufacturing(AM)methods have recently attracted attention from researchers thanks to their great potential for cheap,straightforward,and small-scale production of metallic *** diffusion additive manufacturing(ADAM),a variant of indirect AM methods,is a layer-wise indirect AM process recently developed based on fused deposition modeling and metal injection ***,there is still limited knowledge of the process conditions and material properties fabricated through this process,where sintering plays a crucial role in the final consolidation of ***,this research,for the first time,systematically investigates the impact of various sintering conditions on the shrinkage,relative density,microstructure,and hardness of the 17-4PH ADAM *** this reason,as-washed samples were sintered under different time-temperature *** sample density was evaluated using Archimedes,computed tomography,and image analysis *** outcomes revealed that sintering variables significantly impacted the density of brown 17-4PH Stainless Steel *** results indicated more than 99% relative densities,higher than the value reported by Markforged Inc.(~96%).Based on parallel porosities observed in the computed tomography results,it can be suggested that by modifying the infill pattern during printing,it would be possible to increase the final relative *** microhardness of the sintered samples in this study was higher than that of the standard sample provided by Markforged *** at 1330℃ for 4 h increased the density of the printed sample without compromising its mechanical *** to X-ray diffraction analysis,the standard sample provided by Markforged ***“1330℃—4 h”one had similar stable phases,although copper-rich intermetallics were more abundant in the microstructure of reference *** study is expected to facilitate the adoption of indirect metal AM methods by different sector

关键词： Indirect additive manufacturing Atomic diffusion additive manufacturing 17-4PH stainless steel Computed tomography Sintering

Assessment of electrostatic discharge sensitivity of nitrogen-rich heterocyclic energetic compounds and their salts as high energy-density dangerous compounds:A study of structural variables

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第9期39卷 15-22页

作者： mohammad hossein Keshavarz Sedigheh Heydari Bani Reza Bakhtiari Seyyed Hesamodin hosseini Faculty of Applied Sciences Malek Ashtar University of TechnologyIsfahan 177415875Iran

Nitrogen-rich heterocyclic energetic compounds(NRHECs)and their salts have witnessed widespread synthesis in recent *** substantial energy-density content within these compounds can lead to potentially dangerous explosive reactions when subjected to external stimuli such as electrical ***,developing a reliable model for predicting their electrostatic discharge sensitivity(ESD)becomes *** study proposes a novel and straightforward model based on the presence of specific groups(-NH_(2) or-NH-,-N=N^(+)-O^(-)and-NNO_(2),-ONO_(2) or-NO_(2))under certain conditions to assess the ESD of NRHECs and their salts,employing interpretable structural *** a comprehensive dataset comprising 54 ESD measurements of NRHECs and their salts,divided into 49/5 training/test sets,the model achieves promising *** Root Mean Square Error(RMSE),Mean Absolute Error(MAE),and Maximum Error for the training set are reported as 0.16 J,0.12 J,and 0.5 J,***,the ratios RMSE(training)/RMSE(test),MAE(training)/MAE(test),and Max Error(training)/Max Error(test)are all greater than 1.0,indicating the robust predictive capabilities of the *** presented model demonstrates its efficacy in providing a reliable assessment of ESD for the targeted NRHECs and their salts,without the need for intricate computer codes or expert involvement.

关键词： Electrostatic discharge sensitivity Heterocyclic energetic compounds containing azole compound Interpretable structural parameter Safety

Performance comparison of machine learning algorithms for maximum displacement prediction in soldier pile wall excavation

在线全文

学校读者我要写书评

暂无评论

Underground Space 2024年第3期16卷 301-313页

作者： Danial Sheini Dashtgoli mohammad hossein Dehnad Seyed Ahmad Mobinipour Michela Giustiniani Department of Mathematics Informaticsand GeosciencesUniversity of TriesteTrieste 34127Italy National Institute of Oceanography and Applied Geophysics-OGS Borgo Grotta Gigante 42/CTriesteSgonico 34010Italy Department of Civil Engineering University of QomQom ***Iran

One of the common excavation methods in the construction of urban infrastructures as well as water and wastewater facilities is the excavation through soldier pile *** maximum lateral displacement of pile wall is one of the important variables in controlling the stability of the excavation and its adjacent ***,the application of machine learning methods is widely used in engineering sciences due to its low cost and high speed of *** paper utilized three intelligent machine learning algorithms based on the excavation method through soldier pile walls,namely eXtreme gradient boosting(XGBoost),least square support vector regressor(LS-SVR),and random forest(RF),to predict maximum lateral displacement of pile *** results showed that the implemented XGBoost model performed excellently and could make predictions for maximum lateral displacement of pile walls with the mean absolute error of 0.1669,the highest coefficient of determination 0.9991,and the lowest root mean square error *** the LS-SVR,and RF models were less accurate than the XGBoost model,they provided good prediction results of maximum lateral displacement of pile walls for numerical ***,a sensitivity analysis was performed to determine the most effective parameters in the XGBoost *** analysis showed that soil elastic modulus and excavation height had a strong influence on of maximum lateral displacement of pile wall prediction.

关键词： Soldier pile wall Lateral displacements XGBoost Machine learning Artificial intelligence

Improvement of Surface Mechanical and Tribological Characteristics of L-PBF Processed Commercially Pure Titanium through Ultrasonic Impact Treatment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 1034-1046页

作者： Iman Ansarian Reza Taghiabadi Saeid Amini mohammad hossein Mosallanejad Luca Iuliano Abdollah Saboori Department of Materials Science and Metallurgy Imam Khomeini International University(IKIU)QazvinIran Department of Mechanical Engineering University of KashanKashanIran Integrated Additive Manufacturing Center Department of Management and Production EngineeringPolitecnico di TorinoCorso Duca Degli Abruzzi 2410129TurinItaly

Multi-pass ultrasonic impact treatment(UIT)was applied to modify the microstructure and improve the mechanical and tribological characteristics at the near-surface region of commercially pure Ti(CP-Ti)specimens produced by the laser powder bed fusion(L-PBF)*** considerably refined the L-PBF process-related acicular martensites(α′-M)and produced a well-homogenized and dense surface microstructure,where the porosity content of 1-,3-,and 5-pass UITed samples was reduced by 43,60,and 67%,*** UITed samples showed an enhancement in their near-surface mechanical properties up to a depth of about 300μ*** nanoindentation results for the 3-pass UITed sample revealed an increase of about 53,45,and 220%in its nanohardness,H/E_(r),and H_(3)/E_(r)^(2)indices,*** stylus profilometry results showed that performing the UIT removed the L-PBF-related features/defects and offered a smooth *** roughness average(R_(a))and the skewness(R_(sk))of the 3-pass UITed sample were found to be lower than those of the L-PBFed sample by 95 and 223%,*** the UIT also enhanced the material ratio,where the maximum load-bearing capacity(~100%)in as-L-PBFed(as-built)and 3-pass UITed samples was obtained at 60-and 10-µm depths,*** tribological investigations showed that applying the UIT resulted in a significant reduction of wear rate and average coefficient of friction(COF)of *** instance,under the normal pressures of 0.05 and 0.2 MPa,the wear rate and COF of the 3-pass UITed sample were lower than those of the L-PBFed sample by 65 and 58%,and 20 and 17%,respectively.

关键词： Laser powder bed fusion Ultrasonic impact treatment Commercially pure Ti(CP-Ti) Surface mechanical properties Tribological properties

Er_(2)TiO_(5)@Ag nanocomposites:Enhanced photocatalysis and bacteria inactivation,and cytotoxicity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第5期42卷 851-858,I0002页

作者： Mehdi Nazeri hossein Sedaghat Reza Rafiei mohammad Amin Farzin Seyed Mostafa hosseinpour Mashkani Department of Parasitology and Mycology Kashan University of Medical SciencesKashanIran Department of Microbiology Kashan University of Medical SciencesKashanIran General Medicine Student School of MedicineKashan University of Medical SciencesKashanIran Student Research Committee Kashan University of Medical SciencesKashanIran Institute for Biomedical Materials and Devices School of Mathematical and Physical SciencesFaculty of ScienceUniversity of Technology SydneyNSW2007Australia

In this study,we successfully synthesized Er_(2)TiO_(5)@Ag nanocomposites(NCPs) using the ultrasonicmediated sol-gel technique to create a multifunctional material with enhanced photocatalytic and antibacterial *** visible light photocatalytic activities of Er_(2)TiO_(5) nanoparticles(NPs) and Er_(2)TiO_(5)@Ag NCPs were systematically evaluated under various conditions,including different concentrations of Basic Blue 41(BB 41) dye and *** results reveal a remarkable improvement in the photocatalytic degradation efficiency of Er_(2)TiO_(5)@Ag NCPs(95%) compared to Er_(2)TiO_(5) NPs(80%).Furthermore,the antibacterial efficacy of Er_(2)TiO_(5) NPs and Er2TiO_5@Ag NCPs were extensively examined against Gram-positive and Gram-negative ***,Er_(2)TiO_(5)@Ag NCPs exhibit significantly higher minimum bactericidal concentration(MBC) values compared to Er_(2)TiO_(5) *** antibacterial effect of Er_(2)TiO_(5)@Ag NCPs is particularly pronounced against *** and Pseudomonas aeruginosa,while demonstrating moderate effects on Escherichia coli and Enterococcus *** assess the biocompatibility of the synthesized materials,we investigated their internalization by MCF-7 ***,both Er_(2)TiO_(5) NPs and Er_(2)TiO_(5)@Ag NCPs are found to be effectively internalized by the cells,suggesting their potential application in biomedical ***,our study unveils the exceptional potential of Er_(2)TiO_(5)@Ag NCPs as a dual-action solution,simultaneously possessing enhanced photocatalytic efficiency and potent antibacterial *** multifunctional nanocomposite not only outperforms Er_(2)TiO_(5) and Ag but also paves the way for innovative applications in sustainable environmental remediation and advanced biomedical technologies,promising a brighter and cleaner future.

关键词： Rare earth catalysis Nanocomposite Er_(2)TiO_(5)@Ag Antibacterial activity Photocatalysis Cytotoxicity

Using Longitudinal Fins to Improve the Melting Performance of Stearic Acid in Thermal Energy Storage Devices

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第5期33卷 1672-1687页

作者： YAN Suying LIU Yiran AO Ci ZHAO Xiaoyan ZHANG Na ZHANG Ruiying AHMADI mohammad hossein School of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot 010051China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China School of Materials Science and Engineering Inner Mongolia University of TechnologyHohhot 010051China Faculty of Mechanical Engineering Shahrood University of TechnologyShahroodIran

The heat transfer efficiency of a thermal energy storage unit(TESU)can be improved by the addition of novel longitudinal fins.A series of TESUs are analyzed using the finite volume method(FVM)to determine the effect of fin angle on the heat transfer *** the fin angle increases,the TES rate first increases,then decreases,reaching a maximum rate at 60°,where the melting time is less by 30.9%,28.58%,21.99%,9.02%,and 18.1%than at 0°,15°,30°,45°,and 80°,*** addition,it is found that the melting time of the phase change material is significantly greater at the bottom of the *** time percentage of this stage decreases as the fin angle increases through these percentages by 7%,14%,23%,33%,and 20%,***,the response surface methodology(RSM)is applied to optimize the longitudinal fin by minimizing the total melting *** analysis concludes that a fin angle of 58.68°reduces the complete melting time of the stearic acid by 44%below the time at 0°.These findings fill a gap in knowledge of the effect on melting performance of the design angle of longitudinal fins and provide a reference for the design of horizontally placed longitudinal finned thermal energy storage units.

关键词： thermal energy storage melting rate enhancement longitudinal fins fin angle phase change materials

Insight into small eyes: a practical description from phenotypes presentations to the management

在线全文

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2024年第2期17卷 380-391页

作者： Sana Niazi Sorcha NíDhubhghaill Farideh Doroodgar Zisis Gatzioufas mohammad hossein Dehghan Translational Ophthalmology Research Center Tehran University of Medical SciencesTehran ***Iran Antwerp University Hospital Edegem 2650Belgium Faculty of Health Sciences Antwerp UniversityAntwerpen 2000EdegemBelgium Negah Aref Ophthalmic Research Center Shahid Beheshti University of Medical SciencesTehran 16666Iran University Eye Hospital Basel Basel 4031Switzerland

This narrative review aimed to have an algorithmic approach to microphthalmos by a systematic *** definition can be related to a number of special *** the more challenging cases of complex microphthalmos,relative anterior microphthalmos,and nanophthalmos,the surgeon can approach these cases more safely if they have a deep understanding of the anatomical variations and ideal formulae for intraocular lens computation and knows how to avoid intra-and post-operative *** this article,we review the criteria by which we recognize and describe pre-,intra-,and post-operative considerations,as well as discuss the ideal intraocular lenses for microphthalmos,given the intricate varieties of small eye phenotypes.

关键词： microphthalmos nanophthalmos lenses intraocular anterior chamber axial length eye cataract microcornea syndrome

Introducing a new rock abrasivity index using a scaled down disc cutter

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rock Mechanics Bulletin

Rock Mechanics Bulletin 2024年第3期3卷 24-37页

作者： Maziar Moradi mohammad hossein Khosravi Jafar Khademi Hamidi Department of Civil and Environmental Engineering University of StrathclydeGlasgowG11XQUK Department of Mining Engineering Faculty of EngineeringUniversity of BirjandBirjand ***Iran

Rock abrasivity influences wear of cutting tools and consequently,performance of mechanized tunneling *** methods have been proposed to evaluate rock abrasivity in recent decades,each one has its own *** this paper,a new method is introduced to estimate wear of disc cutters based on rock cutting tests using scaled down discs(i.e.54 and 72 mm diameter).The discs are made of H13 steel,which is a common steel type in producing real-scale discs,with hardness of 32 and 54 *** small-scale linear rock cutting machine and a new abrasion test apparatus,namely University of Tehran abrasivity test machine,are utilized to perform the *** width of the worn discs is monitored and presented as the function of the accumulated test run to classify the rock *** tests show that by increasing the uniaxial compressive strength(UCS)of the rock samples,wear rate is doubled gradually that reveals the sensitivity of the test procedure to the main pa-rameters affecting the abrasivity of hard *** the rocks with the highest UCS,the normal wear stops after performing 5 to 10 rounds of the tests,and then,deformation of the disc tip is *** abrasivity indices are defined based on the abrasivity tests results and their correlations with Cerchar Abrasivity Index(CAI)and UCS are *** of the established correlations in this study with previous investigations dem-onstrates the sensitivity of the indices to the parameters affecting wear of the disc cutters and repeatability of the outputs obtained from abrasivity tests using scaled down *** of this study can be used to enhance the accuracy of rock abrasivity classifications.

关键词： Mechanized tunneling Rock cutting Rock abrasivity classification University of Tehran abrasivity test Wear