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Experimental study on the dynamic response of a 3-D wedge under asymmetric impact

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Journal of Hydrodynamics 2024年第2期36卷 263-274页

作者： saeed Hosseinzadeh Kristjan Tabri Maritime Engineering Research Group School of EngineeringUniversity of SouthamptonSouthamptonUK Department of Civil Engineering and Architecture Tallinn University of TechnologyTallinnEstonia Marine Technology Competence Center Tallinn University of TechnologyKuressaareEstonia

Water entry problems represent complex multiphase flows involving air,water,and structure interaction,occurring rapidly in rough seas,and potentially effecting structural integrity of floating *** paper experimentally investigates asymmetric slamming loads acting on a 3-D elastic wedge *** specimen,featuring two different bottom plates(stiffened and unstiffened),each 4 mm thick,aims to assess the effect of structural stiffness on dynamic *** experiments are conducted at different drop heights of 25 cm and 50 cm and varying heel angles from 5°to 25°.The paper describes the experimental conditions,including wedge geometry,material properties,and the test *** study explores the influence of heel angle on impact acceleration,revealing an increase in peak acceleration with a higher inclination angle,particularly in the vertical ***,the hydrodynamic pressure resulting from asymmetric slamming is *** pressure results analyzed and compared at different locations along the length of the *** experimental findings indicate that,despite the leeward side(stiffened)experiencing a smaller hydrodynamic load,the heel angle significantly affects pressure results on the windward side(unstiffened),leading to a more pronounced dynamic *** time history of pressure results emphasizes the effect of elastic vibrations,particularly noticeable on the unstiffened bottom *** study contributes to a deeper understanding of asymmetric slamming on aluminum structures,facilitating the enhancement of mathematical models and the validation of numerical simulations.

关键词： Flexible fluid structure interactions(FFSI) experimental study asymmetric impact hydrodynamic pressure slamming loads

Coupling of RANS and BEM Solvers for Simulation of Propeller Behind the Hull in Full Appended Model

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China Ocean Engineering 2024年第3期38卷 424-438页

作者： saeed NAJAFI Mehdi POURMOSTAFA LIU Peng-fei Iranian National Institute for Oceanography and Atmospheric Science(INIOAS) Tehran 14155-4781Iran Department of Maritime Engineering Amir Kabir University of TechnologyTehran 15875-4413Iran Marine Offshore and Subsea TechnologySchool of EngineeringNewcastle UniversityNewcastle upon TyneNE17RUUK

To design a propeller for ship power plant,the interaction between ship hull and propeller must be taken into *** main concern is to apply the wake effect of ship stern on the propeller *** this paper,a coupled BEM(Boundary Element Method)/RANS(Renolds-Averaged Navier−Stokes)solver is used to simulate propeller behind the hull in the self-propulsion *** motivation of this work is to develop a practical tool to design marine propulsion system without suffering long computational *** unsteady boundary element method which is also known as panel method is chosen to estimate the propeller *** wakes are treated using a time marching wake alignment ***,a RANS code coupled with VoF equation is developed to consider the ship motions and wake field effects in the problem.A coupling algorithm is developed to interchange ship wake field to the potential flow solver and propeller thrust to the RANS *** on the difference between hull resistance and the propeller thrust,a PI controller is developed to compute the propeller RPM in every time *** of the solver is carried out using the towing tank test report of a 50 m oceanography research *** factor and trust deduction coefficient are estimated ***,the wake rollup pattern of the propeller in open water is compared with the propeller in real wake field.

关键词： RANS BEM coupled method ship propeller self-propulsion wake sheet pattern

Quantum dense coding with gravitational cat states

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Communications in Theoretical Physics 2024年第3期76卷 84-90页

作者： saeed Haddadi Mehrdad Ghominejad Artur Czerwinski Faculty of Physics Semnan UniversityP.O.Box 35195-363SemnanIran Centre for Quantum Optical Technologies Centre of New TechnologiesUniversity of WarsawBanacha 2c02-097 WarszawaPoland

A protocol of quantum dense coding with gravitational cat states is *** explore the effects of temperature and system parameters on dense coding capacity and provide an efficient strategy to preserve the quantum advantage of dense coding for these *** results may open new opportunities for secure communication and insights into the fundamental nature of gravity in the context of quantum information processing.

关键词： quantum dense coding gravitational cat states quantum advantage

Time-dependent effects in transient liquid phase bonding of 304L and Cp-Ti using an Ag-Cu interlayer

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Journal of Central South University 2024年第7期31卷 2237-2255页

作者： saeed VAZIRIAN Mohammad MOSHKBAR BAKHSHAYESH Ali FARZADI Department of Materials and Metallurgical Engineering Amirkabir University of Technology(Tehran Polytechnic)Tehran 15916-34311Iran

One of the challenges for bimetal manufacturing is the joining ***,transient liquid phase(TLP)bonding was performed between 304L stainless steel and Cp-Ti using an Ag-Cu interlayer with a thickness of 75μm for bonding time of 20,40,60,and 90 *** bonding temperature of 860℃ was considered,which is under the β transus temperature of *** TLP bonding,various intermetallic compounds(IMCs),including Ti_(5)Cr_(7)Fe_(17),(Cr,Fe)_(2)Ti,Ti(Cu,Fe),Ti_(2)(Cu,Ag),and Ti_(2)Cu from 304L toward Cp-Ti formed in the ***,on the one side,with the increase in time,further diffusion of elements decreases the blocky IMCs such as Ti_(5)Cr_(7)Fe_(17),(Cr,Fe)_(2)Ti,Ti(Cu,Fe)in the 304L diffusion-affected zone(DAZ)and reaction zone,and on the other side,Ti_(2)(Cu,Ag)IMC transformed into fine morphology toward Cp-Ti *** microhardness test also demonstrated that the(Cr,Fe)_(2)Ti+Ti_(5)Cr_(7)Fe_(17) IMCs in the DAZ on the side of 304L have a hardness value of HV 564,making it the hardest *** maximum and minimum shear strength values are equal to 78.84 and 29.0 MPa,*** cleavage pattern dominated fracture surfaces due to the formation of brittle phases in dissimilar joints.

关键词： diffusion brazing transient liquid phase bonding dissimilar material joints microstructural evolution mechanical properties grade 2 titanium

Quantum speedup and non-Markovianity of an atom in structured reservoirs:pseudomodes as a good description of environmental memory

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Communications in Theoretical Physics 2024年第8期76卷 60-66页

作者： Maryam Hadipour Soroush Haseli saeed Haddadi Faculty of Physics Urmia University of TechnologyUrmiaIran School of Physics Institute for Research in Fundamental Sciences(IPM)PO Box 19395-5531TehranIran Faculty of Physics Semnan UniversityPO Box 35195-363SemnanIran

Following the recent paper(Teittinen et al 2019 New J. Phys. 21 123041), one can see that in general there is no simple relation between non-Markovianity and quantum speed limit. Here, we investigate the connection between quantum speed limit time and non-Markovianity of an atom in structured environments(reservoirs) whose dynamics is governed by an exact pseudomode master equation(Garraway 1997 Phys. Rev. A 55 2290). In particular, we find an inverse relation between them, which means that the non-Markovian feature of the quantum process leads to speedup of evolution. Thus, there is a link between quantum speedup and memory effects for specific cases of dynamical evolution. Our results might shed light on the relationship between the speedup of quantum evolution and the backflow of information from the environment to the system.

关键词： quantum speed limit non-Markovianity pseudomode method structured environments

Techno-aesthetics in architectural discourses:A state of the art review

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Frontiers of Architectural Research 2024年第3期13卷 505-542页

作者： Bita Vasseghipanah saeed Haghir School of Architecture College of Fine ArtsUniversity of TehranTehranIran

Since the beginning of the First Industrial Revolution,technology and its impact on art and design have been a topic of *** the rise of digital technologies,there has been a renewed interest in exploring the relationship between technology and *** aim of this paper is to clarify the concept of techno-aesthetics and make it a more accessible field of study by identifying its key *** order to understand how technological objects have been evaluated in architectural history,a systematic review of 177 studies was *** collected literature was analyzed using Kant’s characteristics of aesthetic judgment,discourse analysis techniques from Foucault’s methodology and Laclau and Mouffe’s discourse *** helped in creating a framework for classifying the *** study analyzed results based on five categories:admired technological objects and architectural objects inspired by them,concepts(function,truth,freedom,objectivity,unity,and power),standpoints(rationalism,romanticism,optimism,and determinism),and benchmarks of legitimation(ideology,history,scientific nature,everyday aesthetics,and sublimation of technology).These results were then combined to identify eleven significant discourses of techno-aesthetics.

关键词： Techno-aesthetics Architectural technologies Order of discourse Discourse theory Aesthetic judgement

Research funding and citations in papers of Nobel Laureates in Physics, Chemistry and Medicine, 2019-2020

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Journal of Data and Information Science 2024年第2期9卷 56-80页

作者： Mario Coccia saeed Roshani CNR-National Research Council of Italy IRCRES-CNRTurin Research Area of the CNRStrada delle Cacce73-10135-TurinItaly Arizona State University School of Complex Adaptive Systems1031 S.Palm WalkTempeAZ 85281-2701USA Allameh Tabataba’i University Department of Technology and Entrepreneurship ManagementDehkadeh-ye-OTehran***Iran

Purpose:The goal of this study is a comparative analysis of the relation between funding(a main driver for scientific research)and citations in papers of Nobel Laureates in physics,chemistry and medicine over 2019-2020 and the same relation in these research fields as a ***/methodology/approach:This study utilizes a power law model to explore the relationship between research funding and citations of related *** study here analyzes 3,539 recorded documents by Nobel Laureates in physics,chemistry and medicine and a broader dataset of 183,016 documents related to the fields of physics,medicine,and chemistry recorded in the Web of Science ***:Results reveal that in chemistry and medicine,funded researches published in papers of Nobel Laureates have higher citations than unfunded studies published in articles;vice versa high citations of Nobel Laureates in physics are for unfunded studies published in ***,when overall data of publications and citations in physics,chemistry and medicine are analyzed,all papers based on funded researches show higher citations than unfunded ***/value:Results clarify the driving role of research funding for science diffusion that are systematized in general properties:a)articles concerning funded researches receive more citations than(un)funded studies published in papers of physics,chemistry and medicine sciences,generating a high Matthew effect(a higher growth of citations with the increase in the number of papers);b)research funding increases the citations of articles in fields oriented to applied research(e.g.,chemistry and medicine)more than fields oriented towards basic research(e.g.,physics).Practical implications:The results here explain some characteristics of scientific development and diffusion,highlighting the critical role of research funding in fostering citations and the expansion of scientific *** finding can support decision-making of policymakers and R&D mana

关键词： Research funding Citations Science diffusion Scientific change Science of Science Power-law distribution Basic research Applied research Matthew effect Nobel Laureates Nobel Prizes

Numerical investigation of supercontinuum generation and optical frequency combs in Si N-based PCF with high nonlinear coefficient

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Optoelectronics Letters 2024年第3期20卷 163-170页

作者： Mohammad Reza Alizadeh Mahmood Seifouri saeed Olyaee Faculty of Electrical Engineering Shahid Rajaee Teacher Training UniversityTehranIran Nano-photonics and Optoelectronics Research Laboratory(NORLab) Shahid Rajaee Teacher Training UniversityTehranIran

In this paper, a photonic crystal fiber(PCF) with a dispersion-engineered and high nonlinear coefficient has been designed for supercontinuum generation(SCG) and frequency comb generation(FCG). The proposed PCF has a Si_(3)N_(4) rod in the core. This rod provides more optical confinement in the core by increasing the refractive index of the core. This high confinement reduces the effective mode area of PCF and thus increases the nonlinear coefficient.

关键词： optical fiber nonlinear

Studying the effect of surfactant assisted low-salinity water flooding on clay-rich sandstones

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Petroleum 2024年第2期10卷 306-318页

作者： saeed Khezerloo-ye Aghdam Alireza Kazemi Mohammad Ahmadi Department of Petroleum Engineering Amirkabir University of Technology (AUT) Department of Petroleum and Chemical Engineering College of Engineering Sultan Qaboos University

Sandstone reservoirs often contain clay particles that can cause damage and reduce permeability during low-salinity water flooding. In this study, the effect of surfactants on fine migration in clay-rich sandstones and its impact on oil recovery was ***, the impact of surfactants on interparticle forces in fine-matrix, fine-fine, and oil-matrix systems was modeled. The results showed that both CTAB(cetyltrimethyl ammonium bromide) and QS(quillaja saponin) cause EDL compaction, weakening the repulsive forces. However, SDS(sodium dodecyl sulfate)and TX(triton X-100) do not affect the EDL. Next, the effect of surfactants on IFT reduction and wettability alteration was experimentally investigated. All surfactants reduced IFT due to the surface excessive concentration mechanism. The wettability alteration experiment illustrated that although QS and CTAB compact EDL around oil and matrix particles leading to attraction force augmentation, they both alter wettability through adsorption on matrix and carboxylic groups present in crude oil, *** aqueous solutions were then injected into various clay-rich sandstone sanpacks, which resulted in increased oil recovery. However, the mechanisms leading to enhanced oil recovery variedby surfactant type. CTAB increased recovery by 10% through IFT reduction and wettability alteration, while SDS and TX increased recovery by 12% and 9%, respectively, through wettability alteration and extreme fine migration. In contrast, partial fine migration in the QS flooding experiment reached a recovery increase of 18%. Permeability trends through experiments were also recorded. During CTAB injection,permeability did not reduce, while QS aqueous solution reduced rock permeability to 5 m D. SDS and TX reduced the magnitude of permeability to 2 m *** conclusion, this study demonstrates that surfactants can effectively improve oil recovery in clay-rich sandstones by altering the interparticle forces, reducing IFT, a

关键词： Surfactant flooding Smart water Fine migration Recovery factor