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Seismic effectiveness evaluation and optimized design of tie up method for securing museum collections

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 741-763页

作者： Wang Meng Yan Yi Yang Weiguo Liu Pei Ge Jiaqi Ma Botao School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China beijing’s Key Laboratory of Structural Wind Engineering and Urban Wind Environment Beijing 100044China beijing General Municipal Engineering design&Research Institute Co. LtdBeijing 100082China China Aviation planning and design Institute(Group)Co.Ltd. Beijing 100120China

To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used for typical museum collection replicas have been carried *** influence of body shape and fixed measure parameters on the seismic responses of replicas and the interaction behavior between replicas and fixed measures have been *** on the results,seismic effectiveness evaluation indexes of the tie up method are *** suggestions for fixed strategies are given,which provide a basis for the exhibition of delicate museum collections considering the principle of minimizing seismic responses and *** analysis results show that a larger ratio of height of mass center to bottom diameter led to more intense rocking *** the initial pretension of fishing lines was conducive to reducing the seismic responses and stress variation of the *** comprehensive consideration of the interaction forces and effective securement,it is recommended to apply 20%of breaking stress as the initial *** specific museum collections that cannot be effectively protected by the independent tie up method,an optimized strategy of a combination of fishing lines and fasteners is recommended.

关键词： tie up method museum collections shaking table test seismic effectiveness optimized design

Joint Probability Analysis and Prediction of Sea Ice Conditions in Liaodong Bay

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Journal of Ocean University of China 2024年第1期23卷 57-68页

作者： LIAO Zhenkun DONG Sheng TAO Shanshan HUA Yunfei JIA Ning College of Engineering Ocean University of ChinaQingdao 266100China Shuifa planning and design Co. Ltd.Jinan 250100China National Hazards Mitigation Service Beijing 100194China

Sea ice conditions in Liaodong Bay of China are often described by sea ice grades,which classify annual sea ice conditions based on the annual maximum sea ice thickness(AM-SIT)and annual maximum floating ice extent(AM-FIE).The joint probability distribution of AM-SIT and AM-FIE was established on the basis of their data pairs from 1949/1950 to 2019/2020 in Liaodong *** joint intensity index of the sea ice condition in the current year is calculated,and the joint classification criteria of the sea ice grades in past years are established on the basis of the joint intensity index series.A comparison of the joint criteria with the 1973 and 2022 criteria revealed that the joint criteria of the sea ice grade match well,and the joint intensity index can be used to quantify the sea ice condition over the years.A time series analysis of the sea ice grades and the joint intensity index sequences based on the joint criteria are then *** show a decreasing trend of the sea ice condition from 1949/1950 to 2019/2020,a mutation in 1990/1991,and a period of approximately 91 years of the sea ice *** addition,the Gray-Markov model(GMM)is applied to predict the joint sea ice grade and the joint intensity index of the sea ice condition series in future years,and the error between the results and the actual sea ice condition in 2020/2021 is small.

关键词： sea ice grade ice thickness floating ice extent Liaodong Bay copula

Surface water resource attenuation attribution and patterns in Hai River Basin

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Science China Earth Sciences 2024年第5期67卷 1545-1560页

作者： Qingming WANG Yong ZHAO Hao WANG Jiaqi ZHAI Yue ZHANG Fan HE Rong LIU Mengyang MA State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research(IWHR)Beijing 100038China Key Laboratory of Water Safety for beijing-Tianjin-Hebei Region of Ministry of Water Resources Beijing 100038China General Institute of Water Resources and Hydropower planning and design Ministry of Water ResourcesBeijing 100120China

From 1956 to 2016,Hai River Basin suffered the most severe surface water resource attenuation among the 10 first-class river basins in *** on the surface water circulation process,and evolving characteristics of precipitation and underlying surface in Hai River Basin,this study attributed the causes of surface water resource attenuation to six primary impact factors,analyzed each factor's quantitative contribution,and revealed four patterns of surface water resource attenuation in Hai River *** pattern of the dominant factor:comparing the 1980–2000 period with the 1956–1979period,the variation of precipitation is the dominant factor of which contribution is 7 billion m^(3),accounting for 59%of total11.7 billion m^(3);comparing the 2001–2016 period with the 1956–1979 period,the increasing of vegetation cover in mountainous area is the dominant factor of which contribution is 2.78 billion m3,accounting for 51%of total 4.9 billion m^(3).The pattern of spatial distributions:comparing the 2001–2016 period with the 1956–1979 period,mountainous areas were more affected by increasing vegetation cover which for example contributed 42%in Luan River Basin mountainous;the plains were more impacted by farmland ridge interception which for example contributed 51%in Beisi River Basin *** pattern of attenuation trend:comparing the 2001–2016 period with the 1980–2000 period,surface water resources in mountainous areas continued to decline,owing to the increasing water consumption of large-scale vegetation restoration,while the influence of the underlying surface changes on surface water resources in plains areas tended to remain *** pattern of reversible change:among factors led to surface water resource attenuation,the human activity,including vegetation cover increase,farmland ridge interception,and urbanization expansion,contributed 36%of the attenuation,which resulted in the variation of precipitation-runoff *** study improved the traditiona

关键词： Hai River Basin Surface water resources Contribution decomposition Quantitative contribution Attenuation patterns

Characteristics and Influencing Factors of Microplastics in Snow in the Inner Mongolia Plateau, China

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Engineering 2024年第6期37卷 69-77页

作者： Hongwei Yu Junrong Shao Huawei Jia Diga Gang Baiwen Ma Chengzhi Hu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Changjiang Survey PlanningDesign and Research Co.Ltd.Wuhan 430010China

Microplastics(MPs;<5 mm)have become one of the most prominent global environmental pollution *** can spread to high altitudes through atmospheric transport and can be deposited by rainfall or snowfall,potentially threatening the structure and function of natural *** in terrestrial and aquatic ecosystems alter the growth and functional characteristics of ***,little attention has been given to the possible harm associated with MPs deposited in snow,particularly in the context of global climate *** collected from surface snow in the Inner Mongolia Plateau,China,were used for quantitative analysis and *** results showed that MPs were easily detected,and the related concentration was approximately(68±10)–(199±22)MPsL1 in snow *** were the most common morphology,the polymer composition was largely varied,and the abundance and composition of MPs were linked to human activity to a great ***-throughput sequencing results showed that the composition and abundance of microorganisms also differed in snow samples from areas with different MP pollution characteristics,indicating a considerable difference in microbial functional *** may have an interference effect on the individual growth and functional expression of microorganisms in *** addition,the results showed that functional living areas(e.g.,landfills and suburban areas)in cities play an important role in the properties of *** instance,the highest abundance of MPs was found in thermal power plants,whereas the abundance of polymers per sample was significantly lower in the suburban *** MP contaminants hidden in snow can alter microbial structure and function and are therefore a potential threat to ecosystem health.

关键词： Human activities Snow Microplastics Microbial community Urban function Environmental effect

Structural optimization design of semi-rigid base asphalt pavement using modulus matching criterion and multi-indicator range analysis

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 131-159页

作者： Zhihao Yang Linbing Wang Dongwei Cao Yinghao Miao Hailu Yang China Airport planning&design Institute Co. Ltd.Beijing 101312China Department of Road and Urban Railway Engineering Beijing University of TechnologyBeijing 100124China National Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China School of Environmental CivilAgricultural and Mechanical EngineeringUniversity of GeorgiaAthensGA 30602USA China-Road Transportation Verification&Inspection Hi-Tech Co. Ltd.Beijing 100088China

Damage to semi-rigid base asphalt pavement is related to improper matching of the pavement structure *** study mainly focused on the modulus matching of structural layers and the development of a pavement structure optimization ***,the modulus loss of existing pavement structures was analysed,and a three-dimensional finite element model was established based on the existing ***,the influence of the modulus of each structural layer on the mechanical response indicators and fatigue life was *** on the results,a pavement structure design method using the smoothness of the stress-strain curve as the modulus matching criterion of the structural layers was *** it was found that a strain convex point was present and that the stress mutation between the structural layers was significant when the modulus matching of the pavement structure was ***,the evaluation indicators were divided into two groups,namely,mechanical indicators and fatigue life *** it was proposed an optimized pavement structure design method based on modulus matching and multi-indicator range ***,the optimal modulus combination of pavement structure was determined by this *** research systematically studied the influence of the modulus of each structural layer on the mechanical response and fatigue life of the pavement,and proposed the concept and specific executive criteria of modulus matching for the first ***,it also provided an effective optimization method for pavement structure design.

关键词： Stress-strain curve Modulus matching Structural optimization design Multi-indicator range analysis Fatigue life

Prediction and validation of diffusive uptake rates for indoor volatile organic compounds in axial passive samplers

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Energy and Built Environment

Energy and Built Environment 2024年第1期5卷 24-31页

作者： Yan Wang Tao Yu Jinhan Mo Department of Building Science Tsinghua UniversityBeijing 100084China beijing Key Laboratory of Indoor Air Quality Evaluation and Control Beijing 100084China Wuhan Second Ship design and Research Institute Wuhan 430205China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Key Laboratory of Eco planning&Green Building Ministry of Education(Tsinghua University)Beijing 100084China

The diffusive uptake rate is essential for using passive samplers to measure indoor volatile organic compounds(VOCs).The traditional theoretical model of passive samplers requires available regression formulas of uptake rates and physicochemical properties of adsorbents to predict the uptake ***,it is difficult to obtain the uptake rates of different VOCs under different sampling periods,and it is also difficult to obtain the physical parameters of adsorbents accurately and *** study provides a reliable numerical prediction method of diffusive uptake rates of *** modeling was based on the standard automated thermal desorption(ATD)tubes packed with Tenax TA and the mass transfer process during *** experimental determinations of toluene uptake rate are carried out to verify the prediction *** uptake rates of typical indoor VOCs are obtained from the literature to calibrate the key apparent parameters in the model by statistical regression *** predicted model can provide the VOC diffusive uptake rates under different sampling duration with an average deviation of less than 5%.This study can provide the basis for fast and accurate prediction of diffusive uptake rates for various VOC pollutants in built environments.

关键词： Indoor air quality Diffusive uptake rate Prediction model Sampling Adsorption

A planning Method for Operational Test of UAV Swarm Based on Mission Reliability

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1889-1918页

作者： Jingyu Wang Ping Jiang Jianjun Qi College of Systems Engineering National University of Defense TechnologyChangsha410073China beijing Special Engineering design Institution Beijing100028China

The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV *** to the high cost and long duration of operational tests,it is essential to plan the test in *** solve the problem of planning UAV swarm operational test,this study considers the multi-stage feature of a UAV swarm mission,composed of launch,flight and combat stages,and proposes a method to find test plans that can maximize mission ***,a multi-stage mission reliability model for a UAV swarm is proposed to ensure successful implementation of the mission.A multi-objective integer optimization method that considers both mission reliability and cost is then formulated to obtain the optimal test *** study first constructs a mission reliability model for the UAV swarm in the combat ***,the launch stage and flight stage are integrated to develop a complete PMS(Phased Mission Systems)reliability ***,the Binary Decision Diagrams(BDD)and Multi Objective Quantum Particle Swarm Optimization(MOQPSO)methods are proposed to solve the *** optimal plans considering both reliability and cost are *** proposed model supports the planning of UAV swarm operational tests and represents a meaningful exploration of UAV swarm test planning.

关键词： UAV swarm PMS MOQPSO BDD mission reliability operational test planning

Pedestrian wind flow prediction using spatial-frequency generative adversarial network

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Building Simulation 2024年第2期17卷 319-334页

作者： Pengyue Wang Maozu Guo Yingeng Cao Shimeng Hao Xiaoping Zhou Lingling Zhao School of Architecture and Urban planning Beijing University of Civil Engineering and ArchitectureBeijing100044China beijing Key Laboratory of Intelligent Processing for Building Big Data Beijing100044China School of Electrical and Information Engineering Beijing University of Civil Engineering and ArchitectureBeijing100044China School of Computer Science and Technology Harbin Institute of TechnologyHarbin150001China

Pedestrian wind flow is a critical factor in designing livable residential environments under growing complex urban *** pedestrian wind flow during the early design stages is essential but currently suffers from inefficiencies in numerical *** learning,particularly generative adversarial networks(GAN),has been increasingly adopted as an alternative method to provide efficient prediction of pedestrian wind ***,existing GAN-based wind flow prediction schemes have limitations due to the lack of considering the spatial and frequency characteristics of wind flow *** study proposes a novel approach termed SFGAN,which embeds spatial and frequency characteristics to enhance pedestrian wind flow *** the spatial domain,Gaussian blur is employed to decompose wind flow into components containing wind speed and distinguished flow edges,which are used as the embedded spatial *** information of wind flow is obtained through discrete wavelet transformation and used as the embedded frequency *** spatial and frequency characteristics of wind flow are jointly utilized to enforce consistency between the predicted wind flow and ground truth during the training phase,thereby leading to enhanced *** results demonstrate that SFGAN clearly improves wind flow prediction,reducing Wind_MAE,Wind_RMSE and the Fréchet Inception Distance(FID)score by 5.35%,6.52%and 12.30%,compared to the previous best method,*** also analyze the effectiveness of incorporating the spatial and frequency characteristics of wind flow in predicting pedestrian wind *** reduces errors in predicting wind flow at large error intervals and performs well in wake regions and regions surrounding *** enhanced predictions provide a better understanding of performance variability,bringing insights at the early design stage to improve pedestrian wind *** proposed spatial-frequen

关键词： pedestrian wind flow prediction generative adversarial network Gaussian kernel wavelet transform objective function

A CAD-BEM geometry transformation method for face-based primary geometric input based on closed contour recognition

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Building Simulation 2024年第2期17卷 335-354页

作者： Jun Xiao Hao Zhou Shiji Yang Deyin Zhang Borong Lin Department of Building Science School of ArchitectureTsinghua UniversityBeijing100084China Key Laboratory of Eco planning&Green Building Ministry of EducationTsinghua UniversityBeijing100084China Institute for Urban Governance and Sustainable Development Tsinghua UniversityBeijing100084China

Performance analysis during the early design stage can significantly reduce building energy ***,it is difficult to transform computer-aided design(CAD)models into building energy models(BEM)to optimize building *** model structures for CAD and BEM are *** this study,geometry transformation methods was implemented in BES tools for the early design stage,including auto space generation(ASG)method based on closed contour recognition(CCR)and space boundary topology calculation *** program is developed based on modeling tools SketchUp to support the CAD format(like*.stl,*.dwg,*.ifc,etc.).It transforms face-based geometric information into a zone-based tree structure model that meets the geometric requirements of a single-zone BES combined with the other thermal parameter inputs of the *** addition,this study provided a space topology calculation method based on a single-zone BEM *** program was developed based on the SketchUp modeling tool to support additional CAD formats(such as*.stl,*.dwg,*.ifc),which can then be imported and transformed into*.*** to current methods mostly focused on BIM-BEM transformation,this method can ensure more modeling *** method was integrated into a performance analysis tool termed MOOSAS and compared with the current version of the transformation *** were tested on a dataset comprising 36 conceptual models without partitions and six real cases with detailed *** ensures a transformation rate of two times in any bad model condition and costs only 1/5 of the time required to calculate each room compared to the previous version.

关键词： geometry transformation building energy model computer aid design closed contour recognition