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Frontiers of Structural and Civil Engineering 2024年第4期18卷 551-567页

作者： Dinh-Nhat TRUONG Van-Lan TO Gia Toai TRUONG hyoun-seung jang Department of Civil Engineering University of Architecture Ho Chi Minh CityHo Chi Minh City 700000Vietnam Faculty of Civil Engineering and Technology Dong A UniversityDa Nang City 550000Vietnam School of Architecture Seoul National University of Science and TechnologySeoul 01811Republic of Korea

Reinforced concrete(RC)flat slabs,a popular choice in construction due to their flexibility,are susceptible to sudden and brittle punching shear *** design methods often exhibit significant bias and *** estimation of punching shear strength in RC flat slabs is crucial for effective concrete structure design and *** study introduces a novel computation method,the jellyfish-least square support vector machine(JS-LSSVR)hybrid model,to predict punching shear *** combining machine learning(LSSVR)with jellyfish swarm(JS)intelligence,this hybrid model ensures precise and reliable *** model’s development utilizes a real-world experimental data *** with seven established optimizers,including artificial bee colony(ABC),differential evolution(DE),genetic algorithm(GA),and others,as well as existing machine learning(ML)-based models and design codes,validates the superiority of the JS-LSSVR hybrid *** innovative approach significantly enhances prediction accuracy,providing valuable support for civil engineers in estimating RC flat slab punching shear strength.

关键词： punching shear strength reinforced concrete flat slabs machine learning jellyfish search support vector machine

Design,Fabrication,and Analysis of Flapping and Folding Wing Mechanism for a Robotic Bird

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Journal of Bionic Engineering 2020年第2期17卷 229-240页

作者： seung Wan Ryu Jong Gu Lee hyoun Jin Kim Department of Mechanical&Aerospace Engineering and Automation Systems Research Institute Seoul National UniversitySeoul 08826Republic of Korea

Emulating periodic main wing movement of a bird for generating lift and thrust remains a significant challenge in developing a robotic *** sequences of main wing motion are comprised of flapping,folding,bending,and *** this paper,we concentrate on the flapping and folding motion,and design two wing mechanisms based on a 4-bar linkage structure:one is only for Flapping Motion(FM)and the other is for simultaneous Flapping and Folding Motion(FFM)during a wing *** derive relationships between length and angle of links to analyze kinematic characteristics of the mechanisms and conduct an optimization to select the length parameters of links that allow maximization of the flapping *** run a simulation to confirm the performance of the optimized parameters by examining physical properties,and fabricate two wing mechanisms *** particular,the folding motion is achieved without using an additional *** measurements to investigate a lift profile of each mechanism and their quantitative comparison of the performance of both types confirm the benefits of the folding motion in the perspectives of wing frequency and *** expect that our kinematic formulation,design procedures,and comparative measurement results can help develop a wing mechanism to create a truly biomimetic robotic bird.

关键词： biomimetic robotic bird flapping and folding wing mechanism wing kinematics force measurement

Electrochemical and electronic properties of nitrogen doped fullerene and its derivatives for lithium-ion battery applications

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Journal of Energy Chemistry 2018年第2期27卷 528-534页

作者： Parveen Sood Ki Chul Kim seung Soon jang School of Materials Science and Engineering Georgia Institute of Technology Atlanta CA 30332-0245. USA Department of Chemical Engineering Konkuk University Seoul 05029 Republic of Korea Institute for Electronics and Nonotechnology Georgia Institute of Technology Atlanta GA 30332-0245 USA Parker H. Petit Institute for Bioengineering and Bioscience Georgia Institute of Technology Atlanta GA 30332-0245 USA

We have studied the redox potentials and electronic properties of C60 and C59N using density functional theory method. It is found that doping C60 with one nitrogen atom results in a slight increase in redox potential. Next, we have also studied C59N functionalized with various redox-active oxygen containing functional groups and strongly electron withdrawing functional groups. It is found that the intrinsic electronic structure of the molecule is the major determinant of the redox potential. Our DFT calculations show that the electron affinity to redox potential of functionalized C59N is correlated with the LUMO of the systems very well. This is the first systematic study on the redox properties and electronic structures of N-doped C60 systems.

关键词： DFT Redox potential C60 Doping Li-ion battery

Rational design of ultrafine FeSe_(2) nanocrystals emb e dde d within hollow mesoporous carbon bowls for potassium-ion batteries with long-term cycling stability and high volumetric capacity

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Journal of Materials Science & Technology 2023年第12期143卷 129-139页

作者： Yu Jin jang Hong Geun Oh seung-Keun Park Department of Advanced Materials Engineering Chung-Ang University4726Seodong-daeroDaedeok-myeonAnseong-siGyeonggi-do 17546Republic of Korea

Hollow structures are commonly used to alleviate the mechanical stress on electrode materials and to provide more active sites in potassium-ion batteries(KIBs).Nevertheless,the excessive internal voids within these structures significantly reduce the packing density of particles,resulting in a relatively low volumetric energy density of the fabricated electrodes,which is undesirable for practical *** designed a hollow mesoporous carbon bowl embedded with ultrafine bis(selanylidene)iron(FeSe 2)nanocrystals(FeSe 2@HMCB)via a controllable impregnation method and subsequent selenization pro-cess for high-performance *** as-obtained FeSe 2@HMCB can inherit the advantages of conventional hollow carbon-based composites,such as alleviation of volume variation in active materials,abundant ion storage sites,and high electrical ***,the bowl structure has a higher pack-ing density than the conventional hollow structure,resulting in a significant increase in the volumet-ric energy density of the fabricated *** of these advantages,the FeSe 2@HMCB exhibits a high,stable reversible capacity of 326 mA h g^(-1) even after 1000 cycles at 0.5 A g^(-1),and excellent rate capacities(182 mA h g^(-1) at 3.0 A g^(-1)).Compared with the hollow structured counterpart,the vol-umetric capacity(mA h cm−3)of FeSe 2@HMCB increased by 60%.Furthermore,a full cell consisting of FeSe 2@HMCB//Prussian blue(PB)exhibits excellent electrochemical performance(99 mA h g^(-1) after 100 cycles at 0.1 A g^(-1)).

关键词： Potassium-ion batteries Iron selenide Bowl-like structure Mesoporous carbon Anode material

Environmental friendly synthesis of hierarchical mesoporous platinum nanoparticles templated by fucoidan biopolymer for enhanced hydrogen evolution reaction

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Journal of Materials Science & Technology 2020年第11期42卷 185-190页

作者： seung Man Lim Kyunglee Kang Hongje jang Jung Tae Park Department of Chemical Engineering Konkuk University120 Neungdong-roGwangjin-guSeoul 05029Republic of Korea Department of Chemistry Kwangwoon University20 Cwangwoon-roNowon-guSeoul 01897Republic of Korea

Researching novel hydrogen evolution reaction(HER)catalysts with enhanced electrocatalytic activity,excellent stability,and cost-efficiency is of great significance for the large-scale hydrogen production from industrial electrolysis *** report the preparation of hierarchical mesoporous-Pt nanoparticles(HM-Pt NPs)with coral-like rough surface morphologies using environmental friendly and biocompatible fucoidan(Fu)biopolymer as a surface engineering compound and its application to electrocatalysts for *** designed HM-Pt NPs yields better mass activity of electrocatalysts compared to a commercial Pt/***-Pt NPs showed an overpotential of 33 mV at 10 mA cm-2 for the HER in 0.5 MH2SO4,which was highly comparable to that of the commercial Pt/C catalysts(29 mV).However,the amount of HM-Pt NPs loaded in glassy carbon electrode(0.033 mg mL-1)was approximately 20 times lower than that of the commercial Pt/C(0.64 mg *** HM-Pt NPs also maintained high catalytic stability with a consistent HER current density after 1000 continuous *** excellent HER performance is attributed to the improved electrochemical surface area,highly porous structure,and good surface wettability of the HM-Pt NPs,which results in enhanced electrocatalytic activity,decreased resistance at the electrode/electrolyte interface,and facile penetration of the electrolytes inside the electrode.

关键词： Mesoporous Fucoidan Biopolymer Low Pt content Hydrogen evolution reaction

Properties of ZnO Thin Films Grown on Si (100) Substrates by Pulsed Laser Deposition

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Journal of Materials Science & Technology 2010年第11期26卷 973-976页

作者： Young Rae jang Keon-Ho Yoo seung Min Park Department of Physics Kyung Hee University Department of Chemistry Kyung Hee University

ZnO thin films were grown on Si （100） substrates by pulsed laser deposition using a ZnO *** substrate temperature was varied in the range of room temperature to 800 ℃,and the oxygen partial pressure of 0.1333 Pa （1 m Torr） to 1333 Pa （10 Torr）.The properties of the resulting films were investigated by photoluminescence （PL）,grazing incidence X-ray diffraction （GIXRD）,X-ray photoelectron spectroscopy （XPS）,and field emission scanning electron microscopy （FESEM）.Based on the ultraviolet （UV,～380 nm） to visible emission ratio in the PL spectrum,the optimum growth conditions were determined to be 600 ℃ and 133.3 Pa （1 Torr）,*** oxygen 1s peak in the XPS spectrum was decomposed into two *** peak at lower binding energy increased in intensity with the oxygen partial pressure from 0.1333 Pa （1 m Torr） to 133.3 Pa （1 Torr） while the other peak *** GIXRD curve at the optimum condition showed strong two peaks （002） and （103）.A strong correlation between the （103） peak intensity and the UV emission intensity was found.

关键词： ZnO Pulsed laser deposition Photoluminescence

Effect of grain refinement on phase transformation behavior and mechanical properties of Cu-based alloy

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中国有色金属学会会刊：英文版 2009年第4期19卷 979-983页

作者： Gwon-seung YANG Jong-Kook LEE Woo-Yang jang Department of Advanced Materials Engineering Chosun University Department of Metallurgical Engineering Chosun University

A small amount of misch metal was added to Cu-Zn-Al alloy in order to study its effect on grain refinement,mechanical properties,phase transformation behavior and stabilization of *** is found that the addition of misch metal is very effective for reducing the grain *** coarse grains over 1 000 μm are refined to the size of 30 μm by the addition of 0.43%(mass fraction) misch *** grain size of thermo-mechanically treated alloys is barely affected by cold *** fracture strength and ductility increase significantly with the increase of misch metal content when tensile test is carried out below Mf ***,the fracture strength is larger in the case of post-quench ageing treatment than that in the case of direct quench ageing *** fracture mode is changed from transgranular brittle fracture to ductile fracture with void formation and coalescence by the addition of misch metal.

关键词：铜基合金力学性能相变行为晶粒细化金属拉伸试验晶粒尺寸断裂强度时效处理

Covalent organic frameworks:Design and applications in electrochemical energy storage devices

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InfoMat 2022年第6期4卷 1-35页

作者： Shikai Jin Omar Allam seung Soon jang seung Woo Lee George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGeorgiaUSA Computational NanoBio Technology Laboratory School of Material Science and EngineeringGeorgia Institute of TechnologyAtlantaGeorgiaUSA

As an emerging class of crystalline organic material,covalent organic frameworks(COFs)possess uniform porosity,versatile functionality,and precise control over designated *** from the favorable charge and mass transport pathways offered by the porous framework,COFs can also exhibit designed reversible redox *** the past few years,their potential has attracted a great deal of attention for charge storage and transport applications in various electrochemical energy storage devices,and numerous design strategies have been proposed to enhance the corresponding electrochemical *** review summarizes the working principle and synthesis methods of COFs and discusses significant findings for supercapacitors and various rechargeable battery systems,emphasizing the representative design strategies and their underlying relationship with electrochemical *** addition,key advances achieved by computations are highlighted along with the challenges and prospects in this field.

关键词： covalent organic frameworks rechargeable batteries redox-active electrodes solid electrolyte supercapacitors

Quantitative assessment of the relevance of organic-aniontransporting-polypeptide 1B1 and 2B1 polymorphisms in fexofenadine pharmacokinetic variants via pharmacometrics

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Journal of Pharmaceutical Analysis 2023年第6期13卷 660-672页

作者： Ji-Hun jang seung-Hyun Jeong Yong-Bok Lee Department of Pharmacy College of PharmacyChonnam National UniversityGwangju61186Republic of Korea Department of Pharmacy College of PharmacySunchon National UniversitySuncheon-si57922Republic of Korea

Fexofenadine is useful in various allergic disease ***,the pharmacokinetic variability information and quantitative factor identification of fexofenadine are very *** study aimed to verify the validity of previously proposed genetic factors through fexofenadine population pharmacokinetic modeling and to explore the quantitative correlations affecting the pharmacokinetic *** of the organic-anion-transporting-polypeptide(OATP)1B1 and 2B1 have been proposed to be closely related to fexofenadine pharmacokinetic ***,modeling was performed using fexofenadine oral exposure data according to the OATP1B1-and ***1B1 and 2B1 were identified as effective covariates of clearance(CL/F)and distribution volume(V/F)-CL/F,respectively,in fexofenadine pharmacokinetic ***/F and average steady-state plasma concentration of fexofenadine differed by up to 2.17-and 2.20-folds,respectively,depending on the OATP1B1 *** the individuals with different OATP2B1 polymorphisms,the CL/F and V/F differed by up to 1.73-and 2.00-folds,*** of the areas under the curves following single-and multiple-administrations,and the cumulative ratio were significantly different between OATP1B1-and 2B1-polymorphism *** on quantitative prediction comparison through a model-based approach,OATP1B1 was confirmed to be relatively more important than 2B1 regarding the degree of effect on fexofenadine pharmacokinetic *** on the established pharmacokineticpharmacodynamic relationship,the difference in fexofenadine efficacy according to genetic polymorphisms of OATP1B1 and 2B1 was 1.25-and 0.87-times,respectively,and genetic consideration of OATP1B1 was expected to be important in the pharmacodynamics area as *** population pharmacometrics study will be a very useful starting point for fexofenadine precision medicine.

关键词： OATP1B1 OATP2B1 Fexofenadine Population pharmacometrics Genetic polymorphism

Pharmacokinetic comparison with different assays for simultaneous determination of cis-,trans-cefprozil diastereomers in human plasma

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Journal of Pharmaceutical Analysis 2021年第3期11卷 351-363页

作者： seung-Hyun Jeong Ji-Hun jang Hea-Young Cho Yong-Bok Lee College of Pharmacy Chonnam National University77 Yongbong-roBuk-guGwangju61186Republic of Korea College of Pharmacy CHA University335 Pangyo-roBundang-guSeongnam-siGyeonggi-Do13488Republic of Korea

The purpose of this study was to compare pharmacokinetic(PK)parameters obtained using two newly developed assays,HPLC-UV and UPLC-ESI-MS/*** of assay and results obtained therefrom are very important in PK studies and can have a major impact on the PK-based clinical dose and usage *** this study,we developed two new methods that are most commonly used in biosample analysis and focused on PK parameters obtained from *** HPLC-UV equipped with a Luna-C8 column using UV detector,cefprozil diastereomers were separated using water containing 2%(V/V)acetic acid and acetonitrile as a mobile *** UPLC-ESI-MS/MS equipped with a HALO-C18 column,cefprozil diastereomers were separated using 0.5%(V/V)aqueous formic acid containing 5 mM ammoniumformate buffer and methanol as a mobile *** showed high resolution,sensitivity,and selectivity without interference by plasma *** intra-and inter-day precisions(CV,%)were within 8.88%for HPLC-UV and UPLC-ESI-MS/*** of both methods was 95.67%-107.50%.These two analytical methods satisfied the criteria of international guidance and could be successfully applied to PK *** of PK parameters between two assays confirmed that there is a difference in the predicted minimum plasma concentrations at steady state,which may affect clinical dose and usage ***,we confirmed possible correlation between PK parameters and various biochemical parameters after oral administration of 1000 mg cefprozil to humans.

关键词： Cefprozil diastereomers Comparison HPLC-UV UPLC-ESI-MS/MS Pharmacokinetic parameter Biochemical parameters