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Nano-Micro Letters 2025年第2期17卷 169-186页

作者： Bitgaram Kim Myeong‑Chang Sung Gwang‑Hee Lee Byoungjoon Hwang Sojung Seo Ji‑Hun Seo Dong‑Wan Kim department of Materials Science and engineering Korea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea School of Civil Environmental and Architectural EngineeringKorea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea Materials Science and Chemical engineering Center Institute for Advanced Engineering(IAE)Yongin 17180Republic of Korea

A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety *** study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves ***-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain *** this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 *** situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen *** situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability *** present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs.

关键词： Solid polymer electrolyte Lithium-oxygen batteries Polyrotaxane ion conductivity Hydrophobic chain

Neumann＇s method for boundary problems of thin elastic shells

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Applied Mathematics and Mechanics(English Edition) 2017年第4期38卷 543-556页

作者： Y. S. NEUSTADT department of Civil engineering Samara State Architectural and Building University Samara 443001 Russia

The possibility of using Neumann＇s method to solve the boundary problems for thin elastic shells is studied. The variational statement of the static problems for the shells allows for a problem examination within the distribution space. The convergence of Neumann＇s method is proven for the shells with holes when the boundary of the domain is not completely fixed. The numerical implementation of Neumann＇s method normally requires significant time before any reliable results can be achieved. This paper suggests a way to improve the convergence of the process, and allows for parallel computing and evaluation during the calculations.

关键词： boundary problem thin elastic shell theory Neumann's method variational principle Korn's inequality distribution embedding theorem Green tensor

Sensitivity analysis for axis rotation diagrid structural systems according to brace angle changes

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Earthquake engineering and engineering Vibration 2017年第4期16卷 783-791页

作者： Jae-Kwang Yang Long-Yang Li Sung-Soo Park department of architectural engineering Pusan National UniversityKorea department of architectural engineering Pusan National UniversityDoctor of EngineeringKorea

General regular shaped diagrid structures can express diverse shapes because braces are installed along the exterior faces of the structures and the structures have no columns. However, since irregular shaped structures have diverse variables, studies to assess behaviors resulting from various variables are continuously required to supplement the imperfections related to such variables. In the present study, materials elastic modulus and yield strength were selected as variables for strength that would be applied to diagrid structural systems in the form of Twisters among the irregular shaped buildings classified by Vollers and that affect the structural design of these structural systems. The purpose of this study is to conduct sensitivity analysis for axial rotation diagrid structural systems according to changes in brace angles in order to identify the design variables that have relatively larger effects and the tendencies of the sensitivity of the structures according to changes in brace angles and axial rotation angles.

关键词： sensitivity analysis axial rotation-diagrid structure lateral behaviors

Optimal seismic retrofit model for steel moment resisting frames with brittle connections

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Earthquake engineering and engineering Vibration 2018年第4期17卷 835-847页

作者： Hyo Seon Park Se Woon Choi Byung Kwan Oh department of architectural engineering Yonsei University Center for Structural Health Care Technology in building Yonsei University department of Architecture Catholic University of Daegu department of Civil and Environmental engineering Princeton University

Based on performance-based seismic engineering, this paper proposes an optimal seismic retrofit model for steel moment resisting frames（SMRFs） to generate a retrofit scheme at minimal cost. To satisfy the acceptance criteria for the Basic Safety Objective（BSO） specified in FEMA 356, the minimum number of upgraded connections and their locations in an SMRF with brittle connections are determined by evolutionary computation. The performance of the proposed optimal retrofitting model is evaluated on the basis of the energy dissipation capacities, peak roof drift ratios, and maximum interstory drift ratios of structures before and after retrofitting. In addition, a retrofit efficiency index, which is defined as the ratio of the increment in seismic performance to the required retrofitting cost, is proposed to examine the efficiencies of the retrofit schemes derived from the model. The optimal seismic retrofit model is applied to the SAC benchmark examples for threestory and nine-story SMRFs with brittle connections. Using the retrofit efficiency index proposed in this study, the optimal retrofit schemes obtained from the model are found to be efficient for both examples in terms of energy dissipation capacity, roof drift ratio, and maximum inter-story drift ratio.

关键词： steel moment resisting frame performance-based seismic engineering optimal seismic retrofit evolutionarycomputation

Geometric proportions： The underlying structure of design process for Islamic geometric patterns

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Frontiers of architectural Research 2012年第4期1卷 380-391页

作者： Loai M. Dabbour department of architectural engineering and building Systems Alzaytoonah University of Jordan Amman 11733 Jordan

This paper discusses geometric proportions which serve as a design toot, especially for IsLamic pattern design. The key rote of geometry in Islamic patterns is discussed with relation to proportions which act as the underlying structure of the design process. Evaluations based on spatial structure and esthetic criteria are integrated into the conceptual phase of the design process. Proportions serve two objectives; firstly, in pattern design, proportions are strongly linked to geometry, which can be viewed as a self-guiding method of esthetically proven design. SecondLy, geometric proportions regulate primarily the order of patterns; while at the same time they mediate between the two poles of order and diversity as wetl as among different esthetic revels. This paper anatyzes geometric principles and design features of traditional Istamic patterns, involving geometric proportion anatysis. It also describes the syntheses of Islamic patterns from the perspectives of Islamic cosmology, philosophy and metaphysics of geometry, which can be seen as following a pre-established principle of geometric and proportional design with high accuracy and great precision. Furthermore, the underlying relationship between cosmology and geometry is manifested in Islamic patterns where geometry acts as the vocabulary underpinning the pattern language. These findings support the argument that geometry was independently discovered and applied by Islamic culture as a universal language, constituting one of the most important multicultural symbols in design.

关键词： Geometry Proportions Islamic patterns

Coupled thermo-hygro-mechanical damage model for concrete subjected to high temperatures

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Applied Mathematics and Mechanics(English Edition) 2012年第4期33卷 465-482页

作者：李忠友刘元雪 department of architectural and Civil engineering Logistical Engineering University

Based on the theory of mixtures, a coupled thermo-hygro-mechanical （THM） damage model for concrete subjected to high temperatures is presented in this paper. Concrete is considered as a mixture composed of solid skeletons, liquid water, water va- por, dry air, and dissolved air. The macroscopic balance equations of the model consist of the mass conservation equations of each component and the momentum and energy conservation equations of the whole medium mixture. The state equations and the con- stitutive model used in the model are given. Four final governing equations are given in terms of four primary variables, i.e., the displacement components of soil skeletons, the gas pressure, the capillary pressure, and the temperature. The processes involved in the coupled model include evaporation, dehydration, heat and mass transfer, etc. Through the process of deformation failure and the energy properties, the mechanics damage evo- lution equations are established based on the principle of conversation of energy and the Lemaitre equivalent strain assumption. Then, the influence of thermal damage on the mechanical property is considered.

关键词： concrete high temperature thermo-hygro-mechanical (THM) damagemodel

Effects of stress conditions on rheological properties of granular soil in large triaxial rheology laboratory tests

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Journal of Central South University 2008年第S1期15卷 397-401页

作者：陈晓斌张家生刘宝琛唐孟雄 School of architectural and Civil engineering Central South University Guangzhou Institute of building Science

In order to study the rheological properties of red stone granular soil,a series of rheological experiments were executed on large tri-axial rheological *** 100,200 and 300 kPa confining stress conditions,the rheological tests were carried *** experiment results showed that the stress conditions,especially the stress level were the critical influencing factors of the rheological deformation *** the low stress level(S=0.1),the granular soil showed the elastic properties,and there was no obvious rheological *** the middle stress level(0.20.8) creep curves showed the non-linear viscous plastic rheological ***,under the stress level of S=1.0,the accelerated rheological phase of creep curves occurred at early time with a trend of *** stress level had obvious effects on the final rheological deformation of the soil sample,and the final rheological deformation increments nonlinearly increased with stress *** final rheological deformation increment and step was little under low stress level,while it became large under high stress level,which showed the nonlinearly rheological properties of the granular *** confining pressure also had direct effects on final rheological deformation,and the final rheological deformation linearly increased with confining pressure increments.

关键词： stress conditions granular soil creep large triaxial rheology test redstone granular soil final creep deformation

Shear deformable finite beam elements for composite box beams

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Acta Mechanica Sinica 2014年第2期30卷 223-240页

作者： Nam-Il Kim Dong-Ho Choi department of architectural engineering Sejong University department of Civil and Environmental engineering Hanyang University

The shear deformable thin-walled composite beams with closed cross-sections have been developed for coupled flexural, torsional, and buckling analyses. A theoretical model applicable to the thin-walled laminated composite box beams is presented by taking into account all the structural couplings coming from the material anisotropy and the shear deformation effects. The current composite beam includes the transverse shear and the restrained warping induced shear deformation by using the first-order shear deformation beam theory. Seven governing equations are derived for the coupled axial-flexural-torsional-shearing buckling based on the principle of minimum total potential energy. Based on the present analytical model, three different types of finite composite beam elements, namely, linear, quadratic and cubic elements are developed to analyze the flexural, torsional, and buckling problems. In order to demonstrate the accuracy and superiority of the beam theory and the finite beam elements developed by this study,numerical solutions are presented and compared with the results obtained by other researchers and the detailed threedimensional analysis results using the shell elements of ABAQUS. Especially, the influences of the modulus ratio and the simplified assumptions in stress-strain relations on the deflection, twisting angle, and critical buckling loads of composite box beams are investigated.

关键词： Thin-walled Composite box beam Deflection Twisting angle Buckling load Shear deformation

Minimal cut-based recursive decomposition algorithm for seismic reliability evaluation of lifeline networks

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Earthquake engineering and engineering Vibration 2007年第1期6卷 21-28页

作者：李杰钱摇琨刘威 building engineering department Tongji University

In this paper, a new probabilistic analytical approach, the minimal cut-based recursive decomposition algorithm （MCRDA）, is presented to evaluate the seismic reliability of large-scale lifeline systems. Based on the minimal cut searching algorithm, the approach calculates the disjoint minimal cuts one by one using the basic procedure of the recursive decomposition method. At the same time, the process obtains the disjoint minimal paths of the system. In order to improve the computation efficiency, probabilistic inequality is used to calculate a solution that satisfies the prescribed error bound. A series of case studies show that MCRDA converges rapidly when the edges of the systems have low reliabilities. Therefore, the approach can be used to evaluate large-scale lifeline systems subjected to strong seismic wave excitation.

关键词： minimal cut seismic reliability recursive decomposition algorithm large-scale lifeline system

Characterization and Thermal Conductivity of Modified Graphite/Fatty Acid Eutectic/PMMA Form-Stable Phase Change Material

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Journal of Wuhan University of Technology(Materials Science) 2013年第3期28卷 586-591页

作者：孟多 WANG Lijiu School of Civil and architectural engineering Liaoning University of Technology Institute of building Materials Dalian University of Technology

We prepared and characterized a form-stable composite phase change material （PCM） with higher thermal conductivity. Capric acid（CA）-myristic acid（MA） eutectic as core, poly-methyl methacrylate （PMMA） as supportive matrix and modified graphite （MG） powders serving as the thermal conductance improver were blended by bulk- polymerization method. The composite PCMs with different MG mass fraction （2%, 5%, 7%, 10% and 15%） were characterized by FT-IR, SEM, DSC technique and mechanical tests. Thermal conductivities of the composites were measured by transient hot-wire method. The results indicate that MG powders have been successfully inserted into the CA-MA/PMMA matrix without any chemical reaction with each other. The MG/CA-MA/PMMA composites maintain good thermal storage performance while the thermal conductivity has been enhanced significantly. The composite PCM added with 15 wt% MG powders increases approximately as 195.9% in thermal conductivity. Moreover, the thermal conductivity improvement of the composite PCMs is also verified by the melting-freezing experiment, which is profitable for the heat transfer efficiency in latent heat thermal energy storage system.

关键词： form-stable composite PCM fatty acid eutectic poly-methyl methacrylate modified graphite thermal conductivity