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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.T.Jeong s.W.Lee W.J.kim Department of Materials science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy superplasticity severe plastic deformation Grain size Grain growth

Inclusive quasielastic neutrino-nucleus scattering with energy density functional nuclear models

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Chinese Physics C 2024年第8期48卷 153-158页

作者： K.s.kim soonchul Choi Hana Gil Chang Ho Hyun school of liberal arts and science korea aerospace universitygoyang 10540korea Center for exotic nuclear studies institute for basic sciencedaejeon 34126korea Center for extreme nuclear matters korea universityseoul 02841korea Department of physics education daegu universitygyeongsan 38453korea

In this study,we calculated the inclusive charged-current neutrino-nucleus scattering from ^(40)Ar in the quasielastic *** explore the effect of uncertainties stemming from the nuclear structure,we used the KIDs(Korea-IBs-Daegu-sKKU)nuclear energy density functional and skyrme force models,namely sLy4,skI3,and *** models were selected to have distinct behavior in terms of the density dependence of the symmetry energy and the effective mass of the *** the charged-current neutrino scattering,the single-and double-differential cross sections were calculated for various *** cross sections are reported as a function of the incident neutrino *** theoretical cross sections were compared with experimental data,and the roles of the effective mass and symmetry energy were investigated in terms of charged-current neutrino-nucleus scattering.

关键词： energy density functional neutrino-nucleus scattering symmetry energy effective mass of the nucleon

Dragonfly Interaction Algorithm for Optimization of Queuing Delay in Industrial Wireless Networks

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Journal of Bionic Engineering 2024年第1期21卷 447-485页

作者： sanjay Bhardwaj Da-Hye kim Dong-seong kim Department of IT Convergence Engineering ICT Convergence Research CenterKumoh National Institute of TechnologyGumiSouth Korea

In industrial wireless networks,data transmitted from source to destination are highly *** often leads to the queuing of the data,and poor management of the queued data results in excessive delays,increased energy consumption,and packet ***,a nature-inspired-based Dragonfly Interaction Optimization Algorithm(DMOA)is proposed for optimization of the queue delay in industrial wireless *** term“interaction”herein used is the characterization of the“flying movement”of the dragonfly towards damselflies(female dragonflies)for *** a result,interaction is represented as the flow of transmitted data packets,or traffic,from the source to the base *** includes each and every feature of dragonfly movement as well as awareness of the rival dragonflies,predators,and damselflies for the desired optimization of the queue *** features are juxtaposed as noise and interference,which are further used in the calculation of industrial wireless metrics:latency,error rate(reliability),throughput,energy efficiency,and fairness for the optimization of the queue *** analysis,convergence analysis,the Wilcoxon test,the Friedman test,and the classical as well as the 2014 IEEE Congress of Evolutionary Computation(CEC)on the benchmark functions are also used for the evaluation of DMOA in terms of its robustness and *** results demonstrate the robustness of the proposed algorithm for both classical and benchmarking functions of the IEEE CEC ***,the accuracy and efficacy of DMOA were demonstrated by means of the convergence rate,Wilcoxon testing,and ***,fairness using Jain’s index in queue delay optimization in terms of throughput and latency,along with computational complexity,is also evaluated and compared with other *** results show that DMOA exceeds other bio-inspired optimization algorithms in terms of fairness in queue delay management and average packet *** proposed a

关键词： Dragonfly Damselfly Interaction Queuing delay Optimization Industrial wireless networks

Ag-GsT/HfO_(x)-based unidirectional threshold switching selector with low leakage current and threshold voltage distribution for high-density cross-point arrays

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Rare Metals 2024年第1期43卷 280-288页

作者： Kyoung-Joung Yoo Dae-Yun Kang Nahyun kim Ho-Jin Lee Ta-Hyeong kim Taeho kim Tae Geun kim school of Electrical Engineering Korea UniversitySeoul 02841Republic of Korea

The use of electrochemical-metallization-based volatile threshold switching selectors in cross-point arrays has been widely explored owing to their high on-off ratios and simple ***,these devices are unsuitable for cross-point architectures because of the difficulty in controlling the random filament formation that results in large fluctuations in the threshold voltage during *** this study,we investigated the unidirectional threshold transition characteristics associated with an Ag/GsT/HfO_(x)/Pt-based bilayer selector and demonstrated the occurrence of a low leakage current(stribution of the threshold voltage(Δ0.11 V).The bilayer structure could control the filament formation in the intermediate state through the insertion of an HfO_(x) tunneling *** stacking a bilayer selector with NiO_(x)based resistive random-access memory,the leakage and programming currents of the device could be significantly *** the crossbar array configuration,we performed equivalent circuit analysis of a one-selector oneresistor(1s1R) devices and estimated the optimal array size to demonstrate the applicability of the proposed *** maximum acceptable crossbar array size of the 1s1R device with the Ag/GsT/HfO_(x)/Pt/Ti/NiO_(x)/Pt structure was 5.29×10^(14)(N^(2),N=2.3×10^(7)).

关键词： selector device Tunneling barrier Threshold switching sputtering 1s1R Cross-point array

systematic security Guideline Framework through Intelligently Automated Vulnerability Analysis

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Computers, Materials & Continua 2024年第3期78卷 3867-3889页

作者： Dahyeon kim Namgi kim Junho Ahn Computer Information Technology Korea National University of TransportationChungju27469Korea Department of AI Computer science and Engineering Kyonggi UniversitySuwon16227Korea

This research aims to propose a practical framework designed for the automatic analysis of a product’s comprehensive functionality and security vulnerabilities,generating applicable guidelines based on real-world *** existing analysis of software security vulnerabilities often focuses on specific features or *** partial and arbitrary analysis of the security vulnerabilities makes it challenging to comprehend the overall security vulnerabilities of the *** key novelty lies in overcoming the constraints of partial *** proposed framework utilizes data from various sources to create a comprehensive functionality profile,facilitating the derivation of real-world security *** guidelines are dynamically generated by associating functional security vulnerabilities with the latest Common Vulnerabilities and Exposure(CVE)and Common Vulnerability scoring system(CVss)scores,resulting in automated guidelines tailored to each *** guidelines are not only practical but also applicable in real-world software,allowing for prioritized security *** proposed framework is applied to virtual private network(VPN)software,wherein a validated Level 2 data flow diagram is generated using the spoofing,Tampering,Repudiation,Information Disclosure,Denial of service,and Elevation of privilege(sTRIDE)technique with references to various papers and examples from related *** analysis resulted in the identification of a total of 121 *** successful implementation and validation demonstrate the framework’s efficacy in generating customized guidelines for entire systems,subsystems,and selected modules.

关键词： Framework automation vulnerability analysis security guidelines

CFD-based hull optimization in calm water using adaptive grid deformation method

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Journal of Hydrodynamics 2024年第2期36卷 241-262页

作者： shuguang Wang Yonghwan kim Department of Naval Architecture and Ocean Engineering Seoul National UniversitySeoulKorea

This paper presents an adaptive grid deformation technique for optimizing ship hull forms using computational fluid dynamics(CFD).The proposed method enables accurate and smooth updates of the hull surface and 3-D CFD grids in response to design *** technique incorporates a two-level point-transformation approach to move the grid points by a few design ***,generic B-splines are utilized to transform grid points according to the displacements of the control points within a defined control *** ensures surface modification accuracy and smoothness,similar to those provided by non-uniform rational ***,radial basis functions are used to interpolate the movements of the control points with a limited set of design *** developed method effectively maintains the mesh quality and simulation *** applying this method to surface and grid adaptation,a regression model is proposed in the form of a second-order polynomial to represent the relationship between the geometric parameters and design *** polynomial is then used to introduce geometric ***,a radial basis function surrogate model for the calm-water resistance is constructed to approximate the objective *** enhanced optimization framework is proposed for CFD–based hull optimization and applied to KVLCC2 to validate its feasibility and efficiency.

关键词： Hull-form optimization adaptive grid deformation ship resistance OpenFOAM radial basis function(RBF)surrogate model

Postmortem ^(7)Li NMR analysis for assessing the reversibility of lithium metal electrodes in lithium metal batteries

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Journal of Energy Chemistry 2024年第7期94卷 430-440页

作者： Jaewon Baek sunha kim Hee-Tak kim Oc Hee Han Department of Chemical&Biomolecular Engineering KAISTDaejeon 34141Republic of Korea Metropolitan seoul Center Korea Basic Science InstituteSeoul 03759Republic of Korea Graduate school of Analytical science&Technology Chungnam National UniversityDaejeon 34134Republic of Korea

Despite the proficiency of lithium(Li)-7 NMR spectroscopy in delineating the physical and chemical states of Li metal electrodes,challenges in specimen preparation and interpretation impede its *** this study,we conducted a comprehensive postmortem analysis utilizing ^(7)Li NMR,employing a stan-dard magic angle spinning probe to examine protective-layer coated Li metal electrodes and LiAg alloy electrodes against bare Li metal electrodes within Li metal batteries(LMBs).Our investigation explores the effects of sample burrs,alignment with the magnetic field,the existence of liquid electrolytes,and precycling on the ^(7)Li NMR *** contrasting NMR spectra before and after cycling,we identi-fied alterations in Li^(0) and Li^(+) signals attributable to the degradation of the Li metal *** NMR analyses decisively demonstrate the efficacy of the protective layer in mitigating dendrite and solid elec-trolyte interphase ***,we noted that Li*ions near the Li metal surface exhibit magnetic susceptibility anisotropy,revealing a novel approach to studying diamagnetic species on Li metal elec-trodes in *** study provides valuable insights and practical guidelines for characterizing distinct lithium states within LMBs.

关键词： NMR spectroscopy Lithium-7 Lithium metal battery Electrolyte Electrode-protective layer solid electrolyte interface Magnetic susceptibility anisotropy Lithium-metal NMR signal Diamagnetic^(7)Li NMR signal

A comprehensive review on the resynthesis of ternary cathode active materials from the leachate of Li-ion batteries

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Journal of Energy Chemistry 2024年第8期95卷 446-463,I0010页

作者： Dongwoo kim Hyeoncheol Joo Chanmin kim seoa kim Wan-Yi kim sangwoo Han Joongkil Park soyeon Park Heechul Jung sanghyuk Park Kyungjung Kwon Department of Energy and Mineral Resources Engineering Sejong UniversitySeoul 05006Republic of Korea LIB Recycling Research Group LIB Materials R&D CenterPOSCO HoldingsPohang 37859Republic of Korea Department of Future Energy Convergence Seoul National University of Science&Technology232 Gongreung-roNowon-guSeoul 01811Republic of Korea Autonomous Intelligent Unmanned Flying Vehicles Institute Sejong UniversitySeoul 05006Republic of Korea

This review highlights the importance of recovering valuable metals from spent Li-ion battery(LIB)cathodes through the resynthesis of cathode active materials(CAMs).The resynthesis process of CAMs,a promising recycling method that directly produces CAM precursors from LIB leachate,is *** process encompasses six key steps,including pretreatment,leaching,purification,adjustment of metal concentrations,precursor synthesis,and *** review also investigates the potential introduction of impurity elements during CAM resynthesis and provides tolerance levels for these impurities based on thorough reference ***,it addresses challenges related to the commercialization of the resynthesis ***,this review represents the first comprehensive assessment of CAM resynthesis,including the systematic evaluation of 12 impurity elements(Fe,Li,Al,Cu,C,P,F,Na,Cl,s,Mg,and Zn).Overall,this comprehensive review is poised to support the commercial development of resynthesized CAMs by offering valuable guidelines for managing impurities and streamlining the purification process.

关键词： Li-ion battery Recycling Resynthesis Leachate Impurity

Retinal artery/arteriole occlusion risks after endovascular treatment for unruptured intracranial aneurysm

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stroke & Vascular Neurology 2024年第3期9卷 295-305,I0251-I0263页

作者： Hae Rang kim Min Jeoung kim sunyeup kim Myung soo Chang Dong Joon kim Byung Moon kim Keun Young Park Yong Bae kim Christopher seungkyu Lee suk Ho Byeon sung soo kim seung Won Lee Yong Joon kim Department of Ophthalmology CHA Bundang Medical CenterCHA University College of MedicineSeongnamKorea(the Republic of) Department of Neurosurgery Severance Stroke CenterSeverance HospitalYonsei University College of MedicineSeoulKorea(the Republic of) Department of Neurosurgery Uijeongbu St.Mary’s HospitalThe Catholic University of Korea College of MedicineUijeongbuKorea(the Republic of) Department of Medical AI Sungkyunkwan University School of MedicineSuwonKorea(the Republic of) Department of Ophthalmology Institute of Vision ResearchYonsei University College of MedicineSeoulKorea(the Republic of) Department of Radiology Severance Stroke CenterSeverance HospitalYonsei University College of MedicineSeoulKorea(the Republic of) Department of Precision Medicine Sungkyunkwan University School of MedicineSuwonKorea(the Republic of)

Background To evaluate the association between retinal artery/arteriole occlusion(RAO)and unruptured intracranial aneurysm(UIA).Methods Incident UIA patients from a nationwide cohort(n=253240)were categorised into three groups based on subsequent treatment:observation(n=208993),microsurgical clipping(n=14168)and endovascular treatment(EVT)groups(n=30079).The incidence and the incident time of RAO were *** of RAO and associated risk factors were ***,a hospital cohort comprising 2569 consecutive UIA patients treated at a tertiary hospital was analysed with detailed clinical information of *** In the nationwide cohort analysis,the incidence of RAO was significantly higher in EVT group than in observation and clipping groups,especially within 60 days(early RAO(within 60 days):HR=4.00,95%CI:2.44 to 6.56);delayed RAO(after 60 days:HR=1.74,95%CI:1.13 to 2.68).Multivariable analysis showed that the presence of chronic kidney disease(p=0.009)and use of a balloon microcatheter during the procedure(p=0.013)were associated with a higher risk of *** hospital cohort analysis,11(0.8%)cases of RAO occurred after EVT,whereas none occurred after microsurgical clipping(ps with RAO were younger and received balloon microcatheters more frequently than their *** cases of RAO(90.9%)occurred in paraclinoid aneurysms,where EVT was preferred over microsurgical *** Performing EVT for UIA may increase the risk of subsequent *** should be taken when treating paraclinoid aneurysms with balloon microcatheters.

关键词： treatment nationwide balloon

Graphene quantum dots:preparations,properties,functionalizations and applications

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Materials Futures 2024年第2期3卷 36-84页

作者： Pin Tian Libin Tang Kar-seng Teng shu-Ping lau Kunming Institute of Physics 650223 KunmingYunnanPeople’s Republic of China Department of Electronic and Electrical Engineering Faculty of Science and EngineeringSwansea UniversityBay CampusFabian WaySwansea SA18ENUnited Kingdom Department of Applied Physics The Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China

Zero-dimensional graphene quantum dots(GQDs)exhibit many different properties,such as strong fluorescence,nonzero bandgap and solubility in solvents,compared to two-dimensional *** are biocompatible and have low toxicity;hence,they are widely used in the biomedical *** edge effect of GQDs is of particular interest because edge modification can regulate the performance of *** this review,various preparation methods for GQDs,which can be divided into three main categories,namely top-down,bottom-up and chemical methods,are *** unique optical,electrical,thermal and magnetic properties of GQDs are *** functionalization of GQDs by doping with heteroatoms and forming composites with other materials is studied,and the characteristics of these GQDs are also *** applications of these GQDs in the fields of optics,electricity,optoelectronics,biomedicine,energy,agriculture and other emerging interdisciplinary fields are reviewed to highlight the enormous potential of *** review reports on the recent advancement in GQD research and suggests future directions for the development of GQDs.

关键词： graphene quantum dots:preparations properties functionalizations and applications