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Predicting characteristics of dune bedforms using PSO-LSSVM

International Journal of Sediment Research 2017年第4期32卷 515-526页

作者： Kiyoumars Roushangar seyed mahdi saghebian Dominique Mouaze Division of Hydraulics Department of Civil EngineeringUniversity of Tabriz Morphodynamic Laboratory University of Caen

Dunes have a large influence on hydraulic roughness, and, thereby, on water levels which could affect the navigability of rivers and performance of hydraulic structures. The present study investigated the variation of geometric and topographic characteristics of dune bedforms and flow features as measured in laboratory studies(data sets from laboratory experiments) to estimate the roughness coefficient and characteristics of dune height. The Least Squares Support Vector Machine(LSSVM), which was optimized using Particle Swarm Optimization(PSO), was used as the Meta model approach to predict the values of interest. Developed models were separated into three categories: modeling using flow characteristics,modeling of flow and bedform characteristics, and modeling by using flow and sediment *** was found that for estimation of the roughness coefficient in open channels with dune bedforms,models developed based on flow and sediment characteristics performed more successfully. The model with input parameters of flow and grain Reynolds numbers(Re and R, respectively) and the ratio of the hydraulic radius(R) to the median grain diameter(D) yields a squared correlation coefficient(R2) of0.8609, a coefficient of determination(DC) of 0.7361,and a root mean square error(RMSE) of 0.0034 for a test series of Manning’s roughness coefficient which was the most accurate model. Results proved the key role of flow Reynolds number(Re) values as an input feature for all models predicting the roughness coefficient. Accordingly, classic approaches led to poor results in comparison. On the other hand, results obtained for estimated values of relative dune height led to moderate prediction quality, which albeit,outperformed classic approaches.

关键词： Alluvial channel Hydraulic characteristics Dune Roughness coefficient Least Squares Support Vector machine Particle Swarm Optimization

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Influence of surface roughness of dune bedforms on flow and turbulence characteristics

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International Journal of Sediment Research 2020年第6期35卷 666-678页

作者： Veysel Sadan Ozgur Kirca seyed mahdi saghebian Kiyoumars Roushangar Oral Yagci Istanbul Technical University Department of Civil Engineering Department of Civil Engineering Ahar Branch Islamic Azad University Division of Hydraulics Department of Civil EngineeringUniversity of Tabriz

The current paper investigates the flow and turbulence characteristics over dune bedforms by means of laboratory experiments,where spatially dense and temporally high frequency velocity measurements were *** similar studies are available in the literature,the focus and novelty of the current study is to assess the influence of surface roughness of the dune bedforms on the nearbed *** direct comparison,two different surface roughness heights over idealized,fixed-shaped,high-angled dune bedforms were tested;one with a hydraulically-smooth surface,and the other with a fully-rough *** variation of time-averaged flow as well as turbulence statistics were examined,which was complemented by streamline plots and spectral *** results are interpreted from sediment entrainment and sediment transport points of *** results show that increased dune surface roughness reduces the nearbed flow velocity,but increases the flow velocities at upper *** upward directed flow near the dune crests becomes stronger in the case of smooth surface,while the reattachment point moves further downstream compared to the rough wall *** is concluded that the roughness of the dune surface affects the nearbed flow and turbulence characteristics qualitatively and quantitatively,which is shown to have direct consequences on sediment entrainment characteristics.

关键词： Bedforms Dunes Friction drag Turbulence Grain roughness Form drag

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Assessment of rehabilitation strategies for lakes affected by anthropogenic and climatic changes: A case study of the Urmia Lake, Iran

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Journal of Arid Land 2024年第6期16卷 752-767页

作者： seyed Morteza MOUSAVI Hossein BABAZADEH mahdi SARAI-TABRIZI Amir KHOSROJERDI Department of Water Science and Engineering Science and Research BranchIslamic Azad UniversityTehran 147789-3855Iran

Over the last three decades,more than half of the world's large lakes and wetlands have experienced significant shrinkage,primarily due to climate change and extensive water consumption for agriculture and other human *** desiccation of lakes leads to severe environmental,economic,and social *** Lake,located in northwestern Iran and representing a vital natural ecosystem,has experienced a volume reduction of over 90.0%.Our research evaluated diverse water management strategies within the Urmia Lake basin and prospects of inter-basin water *** study focused on strategies to safeguard the environmental water rights of the Urmia Lake by utilizing the modeling and simulating(MODSIM)*** model simulated changes in the lake's water volume under various *** included diverting water from incoming rivers,cutting agricultural water use by 40.0%,releasing dam water in non-agricultural seasons,treated wastewater utilization,and inter-basin *** hierarchy process(AHP)was utilized to analyze the simulation *** opinions with AHP analysis,acted as a multi-criteria decision-making tool to evaluate the simulation and determine the optimal water supply source priority for the Urmia *** findings underscore the critical importance of reducing agricultural water consumption as the foremost step in preserving the *** this,inter-basin water transfers are suggested,with a detailed consideration of the inherent challenges and limitations faced by the source *** is imperative to conduct assessments on the impacts of these transfers on the downstream users and the potential environmental risks,advocating for a diplomatic and cooperative approach with adjacent *** study also aims to forecast the volumes of water that can be transferred under different climatic conditions—drought,normal,and wet years—to inform strategic water management planning for the Urmia *** to our proj

关键词： climate change drought lake ecological level agricultural water demand inter-basin water transfer

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3D-Printed MOF Monoliths:Fabrication Strategies and Environmental Applications

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Nano-Micro Letters 2024年第12期16卷 358-405页

作者： Hossein Molavi Kamyar Mirzaei mahdi Barjasteh seyed Yahya Rahnamaee Somayeh Saeedi Aliakbar Hassanpouryouzband Mashallah Rezakazemi Department of Chemistry Institute for Advanced Studies in Basic Science(IASBS)Zanjan 45137-66731Iran Department of Chemical and Biological Engineering University at BuffaloThe State University of New YorkBuffaloNY 14260USA Center for Nano-Science and Nanotechnology Institute for Convergence Science&TechnologySharif University of TechnologyTehran 15614Iran Department of Biomedical Engineering Amirkabir University of Technology(Tehran Polytechnic)Hafez Ave.P.O.Box 15875-4413TehranIran Grant Institute School of GeosciencesUniversity of EdinburghWest Main RoadEdinburgh EH93FEUK Faculty of Chemical and Materials Engineering Shahrood University of TechnologyShahroodP.O.Box ***Iran

Metal-organic frameworks(MOFs)have been extensively considered as one of the most promising types of porous and crystalline organic-inorganic materials,thanks to their large specific surface area,high porosity,tailorable structures and compositions,diverse functionalities,and well-controlled pore/size ***,most developed MOFs are in powder forms,which still have some technical challenges,including abrasion,dustiness,low packing densities,clogging,mass/heat transfer limitation,environmental pollution,and mechanical instability during the packing process,that restrict their applicability in industrial ***,in recent years,attention has focused on techniques to convert MOF powders into macroscopic materials like beads,membranes,monoliths,gel/sponges,and nanofibers to overcome these ***-dimensional(3D)printing technology has achieved much interest because it can produce many high-resolution macroscopic frameworks with complex shapes and geometries from digital ***,this review summarizes the combination of different 3D printing strategies with MOFs and MOF-based materials for fabricating 3D-printed MOF monoliths and their environmental applications,emphasizing water treatment and gas adsorption/separation ***,the various strategies for the fabrication of 3D-printed MOF monoliths,such as direct ink writing,seed-assisted in-situ growth,coordination replication from solid precursors,matrix incorporation,selective laser sintering,and digital light processing,are described with the relevant ***,future directions and challenges of 3D-printed MOF monoliths are also presented to better plan future trajectories in the shaping of MOF materials with improved control over the structure,composition,and textural properties of 3D-printed MOF monoliths.

关键词： MOFs 3D-printing Environmental remediation Shaping Monoliths

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Multidisciplinary design optimization of a dual-spin guided vehicle

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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

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Exploring the relationship between Hashimoto's thyroiditis and male fertility:A meta-analytic and meta-regression perspective on hormonal and seminal factors

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Asian pacific Journal of Reproduction 2024年第4期13卷 147-159页

作者： seyed Sobhan Bahreiny Mojtaba Aghaei mahdi Amraei Mohammad Reza Dabbagh Student Research Committee Ahvaz Jundishapur University of Medical SciencesAhvazIran Medical Basic Sciences Research Institute Physiology Research CenterDepartment of PhysiologySchool of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran Thalassemia&Hemoglobinopathy Research Center Health Research InstituteAhvaz Jundishapur University of Medical SciencesAhvazIran USERN Office Ahvaz Jundishapur University of Medical SciencesAhvazIran Department of Biology Faculty of ScienceShahid Chamran University of AhvazAhvazIran

Objective:To explore the relationship between Hashimoto's autoimmune hypothyroidism(HT)and male fertility,focusing on hormonal and seminal ***:A systematic literature search was conducted across databases such as PubMed,Web of Science,EMBASE,Scopus,Cochrane,and Google Scholar,covering studies published from January 2000 to March *** investigating the impact of HT on semen quality parameters and reproductive hormones were *** effect estimates were calculated using standard mean difference(SMD)and 95%confidence intervals(CI).Results:A total of 8 studies with 8965 participants were *** significantly affected semen quality and reproductive hormone ***,there was a notable decrease in progressive morphology(SMD=-0.78;95%CI:-1.40 to-0.17;P=0.01)and sperm motility(SMD=-1.151;95%CI:-1.876 to-0.425;P=0.002).In addition,there were no significant changes in reproductive hormones,although there were elevated levels of luteinizing hormone(SMD=0.437;95%CI:0.000 to 0.874;P=0.050)and follicle-stimulating hormone(SMD=0.293;95%CI:-0.171 to 0.758;P=0.216),with a slight impact on testosterone levels(SMD=-1.143;95%CI:-2.487 to 0.200;P=0.095).Conclusions:This systematic review and meta-analysis provides robust evidence of the detrimental effects of HT on semen quality and reproductive hormones,underscoring the necessity for thorough evaluation and management of thyroid function in male infertility assessments.

关键词： Hashimoto thyroiditis Male fertility Semen quality Reproductive hormones Meta-analysis Meta-regression

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Two-dimensional MOF-based materials:Preparations and applications as electrodes in Li-ion batteries

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Journal of Energy Chemistry 2024年第10期97卷 388-418,I0008页

作者： Narges Nobakht Seyyed Ahmad Etghani Mohammad Hosseini seyed Hamed Aboutalebi Condensed Matter National Laboratory Institute for Research in Fundamental SciencesTehran 19395-5531Iran School of Biological Sciences Institute for Research in Fundamental SciencesTehran 19395-5746Iran BattScout Company London RoadBishopdownSalisbury SP13EnglandUnited Kingdom

Two-dimensional(2D)metal-organic frameworks(MOFs)are rapidly emerging as a unique class of mushrooming family of 2D materials offering distinctive features,such as hierarchical porosity,extensive surface area,easily available active sites,and versatile,adaptable *** promising characteristics have positioned them as highly appealing alternatives for a wide range of applications in energy storage technologies,including lithium ***,the poor conductivity and limited stability of 2D MOFs have limited their real applications in electrochemical energy *** limitations have therefore warranted ongoing research to enhance the performance of 2D *** the significance of 2D MOF-based materials as an emerging class of advanced materials,a multitude of strategy has been devised to address these challenges such as synthesizing 2D conductive MOFs and derivatives along with 2D MOF *** promising approach involves the use of 2D MOF derivatives,including transition metal oxides,which due to their abundant unsatu rated active metal sites and shorter diffusion paths,offer superior electrochemical ***,by combining pristine 2D MOFs with other materials,hybrid 2D MOF materials can be *** hybrids,with their enhanced stability and conductivity,can be directly utilized as active materials in lithium *** the present review,we categorize 2D MOF-based materials into three distinct groups:pristine 2D MOFs,2D MOFderived materials,and 2D MOF hybrid *** synthesis methods for each group,along with their specific applications as electrode materials in lithium-ion batteries,are discussed in *** comprehensive review provides insights into the potential of 2D MOFs while highlighting the opportunities and challenges that are present in this evolving field.

关键词： Li-ion batteries 2D materials 2D metal-organic frameworks Energy storage Synthesis

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A verifiable essential secret image sharing scheme based on HLRs(VESIS-(t,s,k,n))

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CAAI Transactions on Intelligence Technology 2024年第2期9卷 388-410页

作者： Massoud Hadian Dehkordi seyed Taghi Farahi Samaneh Mashhadi Cryptography and Data Security Laboratory School of MathematicsIran University of Science and TechnologyNarmakTehranIran

In traditional secret image sharing schemes,a secret image is shared among shareholders who have the same *** if the shareholders have two different positions,essential and non‐essential,it is necessary to use essential secret image sharing *** this article,a verifiable essential secret image sharing scheme based on HLRs is ***'s share consists of two *** first part is produced by the shareholders,which prevents the fraud of *** second part is a shadow image that is produced by using HLRs and the first part of *** verification of the first part of the shares is done for the first time by using multilinear and bilinear ***,for verifying shadow images,Bloom Filters are used for the first *** proposed scheme is more efficient than similar schemes,and for the first part of the shares,has formal security.

关键词： Bloom Filter cryptography Essential Secret Image Sharing Verifiability

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Theoretical framework of the Isfahani style: Inspiring sustainable aspects of a vernacular urban development

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Frontiers of Architectural Research 2024年第2期13卷 349-369页

作者： Hatef Jafari Sharami seyed Jamalaldin Hosseini Department of Architecture and Urbanism University of EyvanekeyEyvanekey 99888-35918Iran Faculty of Civil and Architecture University of EyvanekeyEyvanekey 99888-35918Iran

The Isfahani style represents a method of traditional Iranian architecture and urban development that existed in the early 20th century and is regarded as a leading model in most traditional Iranian cities. It exhibits several vigorous features contributing to its recognition as a traditional approach to sustainable architecture and urban development. This research endeavors to reveal a theoretical framework beneath these inspiring aspects using the typology of sustainable modern forms, including the hierarchy, passive design strategies, compactness, density, diversity, mixed land use, pluralism, balance, good composition, and integration over time. To this end, the study employs qualitative research methods, drawing from traditional samples, to identify innovative, energy and socially efficient, and low-impact strategies implemented in this vernacular architecture of Iran's semi-arid and hot climates. The findings revealed that the neighborhood concept as a local and plural community (Mahalla) was a vital phenomenon in Iran's urban development. Apparently, the demise of this paradigm effectively played an important role in the numerous challenges regarding the social, energy, and economic viability of modern Iranian cities. Hence, this study presented theoretical frameworks—aligned with sustainable concepts—from the Isfahani style through its analysis, classification, and interpretation, which can contribute to modern urban development.

关键词： Isfahani style Vernacular urban development Sustainable urban development Iranian cities Vernacular architecture

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Correlation between platinum–aluminide coating features and tensile behavior of nickel-based superalloy Rene?80

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Rare Metals 2024年第10期43卷 5391-5402页

作者： Mohammad Mehdi Barjesteh seyed Mehdi Abbasi Karim Zangeneh Madar Kourosh Shirvani Metallic Materials Research Center Malek Ashtar University of Technology (MUT) Department of Advanced Materials and New Energies Iranian Research Organization for Science and Technology (IROST)

The effect of platinum （a rare metal）–aluminide coating parameters on the tensile properties of nickel-based superalloy Rene?80 was evaluated at 871。*** this purpose,initial layers of platinum with different thicknesses （2,4,6 and 8μm） were coated on tensile samples Then,low-temperature high-activity （LTHA） and hightemperature low-activity （HTLA） processes were used for *** of microstructural evaluations using scanning electron microscope （SEM） and phase analysis by X-ray diffraction （XRD） showed a three-layer structure coating for different platinum layer thicknesses and both aluminizing *** the thickness of the platinum layer from 2 to 8μm led to the improvement in the final coating thickness from 91.6 to 102.1μm in *** increase was from 128.1 to 148.6 μm in *** results of hot tensile tests at 871℃ showed a decrease in strength properties of the coated samples compared to the uncoated ***,HTLA and high thicknesses of the initial platinum layer showed an intense *** results of fractographic evaluations abou uncoated samples showed a ductile *** the other hand,coated samples showed a simultaneous ductile and brittle fracture failure *** the main fracture morphology was brittle cleavage fracture which was for the HTLA.

关键词： Aluminizing Fractography Platinum–aluminide Rene®80 Tensile properties

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