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Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations
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作者 M.SAFI M.VAKILIFARD M.J.MAHMOODI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期407-424,共18页
In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency domains.Three different unit-cells,i.e.,2-layer,4-layer,and 6... In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency domains.Three different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into account.Also,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss factor.Following the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COMSOL software.Subsequent parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse modes.The results show that considering the rubber viscoelasticity enhances the wave attenuation performance.Moreover,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal counterpart.The 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz. 展开更多
关键词 layered metamaterial periodic foundation complex dispersion curve wave transmission diagram
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AlphaEarth Foundations:遥感基础大模型的潜力与挑战 被引量:1
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作者 秦其明 《地球信息科学学报》 北大核心 2025年第10期2283-2290,共8页
【目的】随着全球在轨地球观测卫星数量的快速增长,遥感数据呈现爆炸式积累,为地球系统科学研究提供了动态认知全球变化的前所未有机遇;与此同时,也伴生多源异构、标注稀缺、任务泛化不足与数据过载等一系列挑战。【方法】为应对这些瓶... 【目的】随着全球在轨地球观测卫星数量的快速增长,遥感数据呈现爆炸式积累,为地球系统科学研究提供了动态认知全球变化的前所未有机遇;与此同时,也伴生多源异构、标注稀缺、任务泛化不足与数据过载等一系列挑战。【方法】为应对这些瓶颈问题,Google DeepMind提出了AlphaEarth Foundations(AEF),通过整合光学、SAR、LiDAR、气候模拟及文本等多模态数据,构建统一的64维嵌入表征场,实现了跨模态、跨时空的语义一致性的数据融合,并在Google Earth Engine等平台开放。【结果】AEF的主要贡献体现在:①缓解了长期存在的“数据孤岛”问题,建立了全球一致的嵌入层;②通过vMF球面嵌入机制提升了语义相似性度量能力,支持高效的检索与变化检测;③将复杂的预处理与特征工程前置于预训练阶段,使下游应用进入“分析就绪”状态,大幅降低了应用成本。论文指出,AEF的应用潜力释放可分为3个阶段:首先是地表覆盖分类与变化检测;其次是嵌入向量与物理模型深度耦合,推动科学发现;最后有望演化为空间智能基座,成为全球地理空间智能服务的一种基础设施。尽管如此,AEF仍面临若干挑战:①嵌入向量可解释性不足,限制了科学归因和因果分析;②域迁移与跨场景适应性存在不确定性,极端环境下的鲁棒性有待验证;③性能优势需要更多跨区域、独立实验的实证支撑。【结论】AEF以其在数据效率和跨任务泛化方面的突破,代表了遥感与地理空间人工智能研究的新方向,为未来地学研究提供了坚实支撑,但其进一步发展依据可解释性、鲁棒性及真实性验证的持续提升,并将64维嵌入向量通过不同途径转化为可广泛使用的数据资源。 展开更多
关键词 AlphaEarth foundations 遥感基础大模型 多模态融合 嵌入表征 时空建模
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Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components 被引量:1
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作者 Haibin Liu Run Hou +2 位作者 Chenghao Wu Ruishan Xie Shujun Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期425-438,共14页
At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass components.In this study,multi-laye... At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass components.In this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool head.The material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum alloys.The results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center area.Repeated friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped zone.The tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition sample.It is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they can be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping area.The multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components. 展开更多
关键词 aluminum alloy additive manufacturing SOLID-STATE friction stir welding multi-layer multi-pass
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Foundation Models for the Process Industry:Challenges and Opportunities 被引量:1
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作者 Lei Ren Haiteng Wang +3 位作者 Yuqing Wang Keke Huang Lihui Wang Bohu Li 《Engineering》 2025年第9期53-59,共7页
With the emergence of general foundational models,such as Chat Generative Pre-trained Transformer(ChatGPT),researchers have shown considerable interest in the potential applications of foundation models in the process... With the emergence of general foundational models,such as Chat Generative Pre-trained Transformer(ChatGPT),researchers have shown considerable interest in the potential applications of foundation models in the process industry.This paper provides a comprehensive overview of the challenges and opportunities presented by the use of foundation models in the process industry,including the frameworks,core applications,and future prospects.First,this paper proposes a framework for foundation models for the process industry.Second,it summarizes the key capabilities of industrial foundation models and their practical applications.Finally,it highlights future research directions and identifies unresolved open issues related to the use of foundation models in the process industry. 展开更多
关键词 Industrial foundation model Process manufacturing Artificial intelligence-generated content Embodied intelligence Intelligent manufacturing
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Traditional Solution for Foundations in a Lake Environment:Case of the Village Ganviéin the Republic of Benin
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作者 Babilas Hountondji Lambert KAyitchéhou +1 位作者 François de Paule Codo Martin PAina 《Journal of Environmental & Earth Sciences》 2025年第3期316-328,共13页
The problems noted in the structures built on wooden foundation piles in a lake environment required various works to strengthen over time.This work mainly consists of the recovery of the foundation mass by micropiles... The problems noted in the structures built on wooden foundation piles in a lake environment required various works to strengthen over time.This work mainly consists of the recovery of the foundation mass by micropiles due to the increase in loads on the structures,or the recovery of the foundation mass by injection,which is carried out when voids form between the ground and the wooden foundation elements.The high cost of foundation reinforcement methods led the National Agency for the Development of Tourist Heritage in Benin(ANPT)to replace the wooden foundation piles with reinforced concrete piles in the implementation of the project“reinventing the lakeside city of Ganvié”.This article presents an artisanal technology for the creation of reinforced concrete foundation piles in a lake environment.On-site examples made it possible to evaluate the performance of this artisanal implementation technique.The installation of these piles is carried out following manual drilling,followed by the installation of reinforcement and the pouring of concrete on site.The implementation of reinforced concrete foundation piles in place of the wooden ones studied in this article only impacted the infrastructure of the homes of the lakeside town of Ganviébut not the superstructure,which preserved the old traditional wooden architecture and thatched roofs.Thus,the ambition to move this city of Ganviéfrom the stage of a lake village to that of a floating city is very successful.This will contribute to improving the environment and living conditions of the populations and will promote economic development through tourism. 展开更多
关键词 Wooden foundation Piles Disorder of foundations Reinforcement of foundations Manual Drilling Reinforced
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China Foundation for Peace and Development Donated 5 Tons of Medicine to Earthquake-stricken Areas of Myanmar
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《International Understanding》 2025年第2期54-54,共1页
On April 26,the China Foundation for Peace and Development(CFPD),in collaboration with the Shenzhen Foundation for International Exchange and Cooperation(SFIEC),the Shenzhen Ye Chenghai Charity Foundation and the Chin... On April 26,the China Foundation for Peace and Development(CFPD),in collaboration with the Shenzhen Foundation for International Exchange and Cooperation(SFIEC),the Shenzhen Ye Chenghai Charity Foundation and the China-Myanmar Economic Cooperation and Development Promotion Association(Myanmar),held a handover ceremony at Yangon Airport to donate five tons of medicine to the disasterstricken areas of Myanmar. 展开更多
关键词 Myanmar China foundation Peace Development Shenzhen foundation International Exchange Cooperation DONATION MEDICINE earthquake handover ceremony Shenzhen Ye Chenghai Charity foundation
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An improved model of the Pasternak foundation beam umbrella arch considering the generalized shear force
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作者 CHEN Lei JIA Chao-jun +3 位作者 LEI Ming-feng HE Yan-chun SHI Cheng-hua LI Ao 《Journal of Central South University》 2025年第4期1503-1519,共17页
The existing analytical models for umbrella arch method(UAM)based on elastic foundation beams often overlook the influence of the surrounding soil beyond the beam edges on the shear stresses acting on the beam.Consequ... The existing analytical models for umbrella arch method(UAM)based on elastic foundation beams often overlook the influence of the surrounding soil beyond the beam edges on the shear stresses acting on the beam.Consequently,such models fail to adequately reflect the continuity characteristics of soil deformation.Leveraging the Pasternak foundation-Euler beam model,this study considers the generalized shear force on the beam to account for the influence of soil outside the beam ends on the shear stress.An analytical model for the deformation and internal forces of finite-length beams subjected to arbitrary loads is derived based on the initial parameter method under various conditions.The mechanical model of the elastic foundation beam for advanced umbrella arch under typical tunnel excavation cycles is established,yielding analytical solutions for the longitudinal response of the umbrella arch.The reliability of the analytical model is verified with the existing test data.The improved model addresses anomalies in existing models,such as abnormal upward deformation in the loosened segment and maximum deflection occurring within the soil mass.Additionally,dimensionless characteristic parameters reflecting the relative stiffness between the umbrella arch structure and the foundation soil are proposed.Results indicate that the magnitude of soil characteristic parameters significantly influences the deformation and internal forces of the umbrella arch.Within common ranges of soil values,the maximum deformation and internal forces of the umbrella arch under semi-logarithmic coordinates exhibit nearly linear decay with decreasing soil characteristic parameters.The impact of tunnel excavation height on the stress of unsupported sections of the umbrella arch is minor,but it is more significant for umbrella arch buried within the soil mass.Conversely,the influence of tunnel excavation advance on the umbrella arch is opposite. 展开更多
关键词 elastic foundation beam Pasternak foundation generalized shear umbrella arch analytical model
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Bridge Builder Hu Junhui is leading the Tianfu Association(Singapore)to integrate into Singapore and sets up Tianfu Foundation of the Community Foundation of Singapore(CFS)
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作者 Huang Jiangqin 《China Report ASEAN》 2025年第8期39-39,共1页
Hu Junhui,president of Tianfu Association(Singapore)and recipient of the Public Service Medal(PBM),has been leading community efforts to help new Chinese immigrants integrate into Singaporean society.Originally from H... Hu Junhui,president of Tianfu Association(Singapore)and recipient of the Public Service Medal(PBM),has been leading community efforts to help new Chinese immigrants integrate into Singaporean society.Originally from Hebei Province in China,Hu arrived in Singapore in 1994 as one of the first technical professionals dispatched by China.Since then,he has built a life and career firmly rooted in Singapore.Over more than four years at China Construction(South Pacific)Development Co Pte Ltd,he rose through the ranks from project engineer to site manager and eventually project director.In 1999,he left the company to start his own business,setting up a construction firm with several partners.His focus shifted to real estate in 2007,when he co-founded JVA Venture Pte Ltd. 展开更多
关键词 Tianfu foundation technical professionals Community foundation Singapore CFS public service medal PBMs Chinese immigrants Hu Junhui integration Tianfu Association Singapore
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A Multi-Layer Progressive Analysis Method for Collision Energy Flow in Rail Trains
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作者 Jingke Zhang Tao Zhu +4 位作者 Xiaorui Wang Bing Yang Shoune Xiao Guangwu Yang Yuru Li 《Chinese Journal of Mechanical Engineering》 2025年第5期425-439,共15页
The huge impact kinetic energy cannot be quickly dissipated by the energy-absorbing structure and transferred to the other vehicle through the car body structure,which will cause structural damage and threaten the liv... The huge impact kinetic energy cannot be quickly dissipated by the energy-absorbing structure and transferred to the other vehicle through the car body structure,which will cause structural damage and threaten the lives of the occupants.Therefore,it is necessary to understand the laws of energy conversion,dissipation and transfer during train collisions.This study proposes a multi-layer progressive analysis method of energy flow during train collisions,considering the characteristics of the train.In this method,the train collision system is divided into conversion,dissipation,and transfer layers from the perspective of the train,collision interface,and car body structure to analyze the energy conversion,dissipation and transfer characteristics.Taking the collision process of a rail train as an example,a train collision energy transfer path analysis model was established based on power flow theory.The results show that when the maximum mean acceleration of the vehicle meets the standard requirements,the jerk may exceed the allowable limit of the human body,and there is a risk of injury to the occupants of a secondary collision.The decay rate of the collision energy along the direction of train operation reaches 79%.As the collision progresses,the collision energy gradually converges in the structure with holes,and the structure deforms when the gathered energy is greater than the maximum energy the structure can withstand.The proposed method helps to understand the train collision energy flow law and provides theoretical support for the train crashworthiness design in the future. 展开更多
关键词 Train Cllision multi-layer Progression Energy Flow Energy Conversion Energy Dissipation Energy Transfer
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Efficacy Evaluation Method for Foundation Products in vivo and vitro
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作者 Peng Tingting Guo Junbin +2 位作者 He Lina Guo Shentao Tan Yong 《China Detergent & Cosmetics》 2025年第2期38-44,共7页
Establish an efficacy evaluation method for foundation products in vivo and vitro.The hiding power,whiteness,waterproof and anti-sweat effect were evaluated in vitro test,where CR ratio,Individual Type Angle (ITA°... Establish an efficacy evaluation method for foundation products in vivo and vitro.The hiding power,whiteness,waterproof and anti-sweat effect were evaluated in vitro test,where CR ratio,Individual Type Angle (ITA°) and chromatic aberration (E) were measured as evaluation indicators by standard black/white cardboard,artificial leather and artificial sweat.In clinical assessment,the anti-stain,waterproof,anti-sweat effect of the foundation products were evaluated through the ΔE change,before and after the treatment of products by staining,wetting,sweating in forearm skin.There were significant differences in CR ratio of different types of samples on standard black and white cardboards (P<0.05),ITA° of artificial leather has a significant increase after treatment (P<0.05),?E﹤1.5 in black cloth after dipping test,while ΔE﹤1.5 in leather after water and artificial sweat treatment.Clinical assessment showed that ?E ﹤50%,which had no significant difference in human skin color,before and after the test (P>0.05).The change trend of efficacy evaluation in vitro test was basically consistent with that of visual evaluation and clinical assessment,indicated that the efficacy evaluation methods of foundation products in vivo and vitro are intuitive,quantifiable,and can be used to evaluate the efficacy of foundation products. 展开更多
关键词 foundation products hiding power physical whitening anti-stain WATERPROOF anti-sweat
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Intrusion Detection Model on Network Data with Deep Adaptive Multi-Layer Attention Network(DAMLAN)
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作者 Fatma S.Alrayes Syed Umar Amin +2 位作者 Nada Ali Hakami Mohammed K.Alzaylaee Tariq Kashmeery 《Computer Modeling in Engineering & Sciences》 2025年第7期581-614,共34页
The growing incidence of cyberattacks necessitates a robust and effective Intrusion Detection Systems(IDS)for enhanced network security.While conventional IDSs can be unsuitable for detecting different and emerging at... The growing incidence of cyberattacks necessitates a robust and effective Intrusion Detection Systems(IDS)for enhanced network security.While conventional IDSs can be unsuitable for detecting different and emerging attacks,there is a demand for better techniques to improve detection reliability.This study introduces a new method,the Deep Adaptive Multi-Layer Attention Network(DAMLAN),to boost the result of intrusion detection on network data.Due to its multi-scale attention mechanisms and graph features,DAMLAN aims to address both known and unknown intrusions.The real-world NSL-KDD dataset,a popular choice among IDS researchers,is used to assess the proposed model.There are 67,343 normal samples and 58,630 intrusion attacks in the training set,12,833 normal samples,and 9711 intrusion attacks in the test set.Thus,the proposed DAMLAN method is more effective than the standard models due to the consideration of patterns by the attention layers.The experimental performance of the proposed model demonstrates that it achieves 99.26%training accuracy and 90.68%testing accuracy,with precision reaching 98.54%on the training set and 96.64%on the testing set.The recall and F1 scores again support the model with training set values of 99.90%and 99.21%and testing set values of 86.65%and 91.37%.These results provide a strong basis for the claims made regarding the model’s potential to identify intrusion attacks and affirm its relatively strong overall performance,irrespective of type.Future work would employ more attempts to extend the scalability and applicability of DAMLAN for real-time use in intrusion detection systems. 展开更多
关键词 Intrusion detection deep adaptive networks multi-layer attention DAMLAN network security anomaly detection
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The research progress on periodontitis by the National Natural Science Foundation of China
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作者 Liang Xie Qian Chen +3 位作者 Hao Xu Cui Li Jiayu Lu Yuangui Zhu 《International Journal of Oral Science》 2025年第4期449-465,共17页
Periodontitis has emerged as one of the most critical oral diseases, and research on this condition holds great importance for the advancement of stomatology. As the most authoritative national scientific research fun... Periodontitis has emerged as one of the most critical oral diseases, and research on this condition holds great importance for the advancement of stomatology. As the most authoritative national scientific research funding institution in China, the National Natural Science Foundation of China (NSFC) has played a pivotal role in driving the progress of periodontal science by supporting research on periodontitis. This article provides a comprehensive review of the research and development progress related to periodontitis in China from 2014 to 2023, highlighting the significant contributions of the NSFC to this field. We have summarized the detailed funding information from the NSFC, including the number of applicant codes, funded programs and the distribution of funded scholars. These data illustrate the efforts of the NSFC in cultivating young scientists and building research groups to address key challenges in national scientific research. This study offers an overview of the current hot topics, recent breakthroughs and future research prospects related to periodontitis in China. 展开更多
关键词 progress periodontal science oral diseases national scientific research funding institution advancement stomatology PERIODONTITIS national natural science foundation china national natural science foundation research progress
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Towing Performance and Influencing Factors of Integrated Wellhead Platform with Rounded Rectangular Bucket Foundation
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作者 ZHANG Puyang LI Jingyi +2 位作者 BAI Yu LE Conghuan DING Hongyan 《Journal of Ocean University of China》 2025年第2期303-322,共20页
For the development of an integrated rounded rectangular wellhead platform with a bucket foundation,a model test was conducted to study the towing motion response of such a structure under still water and wave conditi... For the development of an integrated rounded rectangular wellhead platform with a bucket foundation,a model test was conducted to study the towing motion response of such a structure under still water and wave conditions.The influence of various factors on the floating stability of the structure was investigated through alterations of the towing conditions(draft,towing point position,and wave conditions),and the related influencing mechanism was analyzed.Comparison and analysis were performed to determine the changes in the structure motion pattern and various effects of towing conditions on the structure during towing in still water and regular waves.Moreover,the influence of each factor on the structure’s motion response during towing was analyzed using the Apriori algorithm.In addition,for the simulation of the towing process under actual sea conditions,a towing test was performed under irregular waves,and the stability of towing in irregular waves was compared with that in regular waves. 展开更多
关键词 bucket foundation floating towing motion response model test
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Influence of Porosity on Vibration of Porous FG Plates Resting on an Arbitrarily Orthotropic Winkler-Pasternak Foundation by PDDO
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作者 Yongyu Yang Xiaoqi Wang +3 位作者 Hang Zhao Chao Wang Changzheng Cheng Raj Das 《Acta Mechanica Solida Sinica》 2025年第1期142-151,共10页
This paper studies the vibration responses of porous functionally graded(FG)thin plates with four various types of porous distribution based on the physical neutral plane by employing the peridynamic differential oper... This paper studies the vibration responses of porous functionally graded(FG)thin plates with four various types of porous distribution based on the physical neutral plane by employing the peridynamic differential operator(PDDO).It is assumed that density and elastic modulus continuously vary along the transverse direction following the power law distribution for porous FG plates.The governing differential equation of free vibration for a porous rectangular FG plate and its associated boundary conditions are expressed by a Lévy-type solution based on nonlinear von Karman plate theory.Dimensionless frequencies and mode shapes are obtained after solving the characteristic equations established by PDDO.The results of the current method are validated through comparison with existing literature.The effects of geometric parameters,material properties,elastic foundation,porosity distribution,and boundary conditions on the frequency are investigated and discussed in detail.The highest fundamental dimensionless frequency occurs under SCSC boundary conditions,while the lowest is under SFSF boundary conditions.The porous FG plate with the fourth pore type,featuring high density of porosity at the top and low at the bottom,exhibits the highest fundamental frequency under SSSS,SFSF,and SCSC boundary conditions.The dimensionless frequency increases with an increase in the elastic foundation stiffness coefficient. 展开更多
关键词 Vibration response Porous FG plate Orthotropic Winkler-Pasternak foundation PDDO
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Application of Deep Foundation Pit Construction Technology in Civil Engineering Construction
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作者 Nan Jiang 《Journal of Architectural Research and Development》 2025年第1期46-51,共6页
As one of the commonly used technologies in modern civil engineering,the construction technology is becoming more and more widely used with the continuous growth of building height.In the construction process of highr... As one of the commonly used technologies in modern civil engineering,the construction technology is becoming more and more widely used with the continuous growth of building height.In the construction process of highrise buildings,the deep foundation pit support provides the necessary stability for the foundation structure of the building project,and more effectively guarantees the quality of the project.Through the reasonable supporting structure,the deep foundation pit technology can effectively prevent the risk of soil collapse,foundation pit deformation and other risks,and improve the safety factor of the whole construction project.Especially in the high-rise buildings,the deep foundation pit support technology can consolidate the foundation for the long-term stability of the project,and significantly prolong the service life of the building.The continuous development of deep foundation pit construction technology is the inevitable demand of high-rise building construction,and also provides a powerful help for the development of civil engineering industry.Based on this,this paper focuses on the application of deep foundation pit construction technology in civil engineering construction. 展开更多
关键词 Civil engineering Deep foundation pit construction technology APPLICATION
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Streamlined photoacoustic image processing with foundation models:A training-free solution
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作者 Handi Deng Yucheng Zhou +5 位作者 Jiaxuan Xiang Liujie Gu Yan Luo Hai Feng Mingyuan Liu Cheng Ma 《Journal of Innovative Optical Health Sciences》 2025年第1期55-65,共11页
Foundation models(FMs)have rapidly evolved and have achieved signicant accomplishments in computer vision tasks.Specically,the prompt mechanism conveniently allows users to integrate image prior information into the m... Foundation models(FMs)have rapidly evolved and have achieved signicant accomplishments in computer vision tasks.Specically,the prompt mechanism conveniently allows users to integrate image prior information into the model,making it possible to apply models without any training.Therefore,we proposed a workflow based on foundation models and zero training to solve the tasks of photoacoustic(PA)image processing.We employed the Segment Anything Model(SAM)by setting simple prompts and integrating the model's outputs with prior knowledge of the imaged objects to accomplish various tasks,including:(1)removing the skin signal in three-dimensional PA image rendering;(2)dual speed-of-sound reconstruction,and(3)segmentation ofnger blood vessels.Through these demonstrations,we have concluded that FMs can be directly applied in PA imaging without the requirement for network design and training.This potentially allows for a hands-on,convenient approach to achieving efficient and accurate segmentation of PA images.This paper serves as a comprehensive tutorial,facilitating the mastery of the technique through the provision of code and sample datasets. 展开更多
关键词 foundation models photoacoustic imaging image segmentation large model
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Numerical Simulation of M-Shaped Multi-Row Pile-Supported Foundation Pit Excavation Based on ABAQUS
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作者 Meng Chen Chuanteng Huang +3 位作者 Shuang Pu Jilun Cai Zuocai Li Yufu Huang 《Journal of World Architecture》 2025年第3期55-63,共9页
The M-shaped multi-row pile foundation retaining structure represents an enhanced version of conventional multi-row anti-sliding support systems.To date,the implementation of M-shaped pile configurations in foundation... The M-shaped multi-row pile foundation retaining structure represents an enhanced version of conventional multi-row anti-sliding support systems.To date,the implementation of M-shaped pile configurations in foundation pit excavations has not been extensively investigated,with particularly scant research focusing on their load-bearing mechanisms and stress redistribution characteristics.Furthermore,numerical modeling methodologies for such geometrically optimized pile networks remain underdeveloped compared to practical engineering applications,creating a notable research-practice gap in geotechnical engineering.A comparative finite element analysis was systematically conducted using ABAQUS software to establish three distinct excavation support configurations:single-row cantilever retaining structures,three-row cantilever configurations,and M-shaped multi-row pile foundation systems.Subsequent numerical simulations enabled quantitative comparisons of critical performance indicators,including pile stress distribution patterns,lateral displacement profiles,and bending moment diagrams across different structural typologies.The parametric investigation revealed characteristic mechanical responses associated with each configuration,establishing corresponding mechanical principles governing the interaction between pile topology and soil-structure behavior towers.The findings of this study provide critical references for the design optimization of M-shaped multi-row pile foundation retaining systems. 展开更多
关键词 M-shaped multi-row piles foundation pit excavation Numerical simulation ABAQUS
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Seismic response of existing stone masonry structures on soft soil foundations
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作者 Xin Zhao Haojiang Shang Yingxiong Wu 《Earthquake Research Advances》 2025年第3期88-99,共12页
The coastal region of Fujian contains numerous existing stone masonry structures,many of which are constructed on soft soil sites.Previous studies have shown that the soil-structure interaction(SSI)effect on soft soil... The coastal region of Fujian contains numerous existing stone masonry structures,many of which are constructed on soft soil sites.Previous studies have shown that the soil-structure interaction(SSI)effect on soft soil foundations can prolong the structure's natural vibration period and enhance its seismic response.We develops a soilstructure interaction system model and a comparative rigid foundation model using the finite element software LS-DYNA to investigate the impact of SSI on the dynamic characteristics and seismic response of stone structures.The results indicate that the SSI effect alters stone structures'dynamic properties and seismic response.This alteration is evident in the extended natural vibration period,which reduces overall stiffness,increases interstory displacement angles,and slightly decreases the acceleration response.Under both SSI and FIX systems,the structural failure mode is characterized by the external collapse of the second-story stone walls,which causes the roof stone slabs to lose support and fall,leading to overall collapse.The FIX system demonstrates better structural integrity and stability with slower crack development.In contrast,the SSI system exhibits cracks that appear earlier and develop more rapidly,causing more severe damage.The research findings provide a theoretical basis for the seismic reinforcement of existing stone structures on soft soil foundations. 展开更多
关键词 Stone structure Soft soil foundation Soil-structure interaction Seismic response LS-DYNA
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An improved model for predicting thermal contact resistance at multi-layered rock interface
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作者 WEN Min-jie XIE Jia-hao +4 位作者 LI Li-chen TIAN Yi EL NAGGAR M.Hesham MEI Guo-xiong WU Wen-bing 《Journal of Central South University》 2025年第1期229-243,共15页
This study proposes a general imperfect thermal contact model to predict the thermal contact resistance at the interface among multi-layered composite structures.Based on the Green-Lindsay(GL)thermoelastic theory,semi... This study proposes a general imperfect thermal contact model to predict the thermal contact resistance at the interface among multi-layered composite structures.Based on the Green-Lindsay(GL)thermoelastic theory,semi analytical solutions of temperature increment and displacement of multi-layered composite structures are obtained by using the Laplace transform method,upon which the effects of thermal resistance coefficient,partition coefficient,thermal conductivity ratio and heat capacity ratio on the responses are studied.The results show that the generalized imperfect thermal contact model can realistically describe the imperfect thermal contact problem.Accordingly,it may degenerate into other thermal contact models by adjusting the thermal resistance coefficient and partition coefficient. 展开更多
关键词 multi-layered structures general thermal contact model thermal contact resistance GL thermoelastic theory Laplace transform
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Improving Shallow Foundation Settlement Prediction through Intelligent Optimization Techniques
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作者 Hadi Fattahi Hossein Ghaedi Danial Jahed Armaghani 《Computer Modeling in Engineering & Sciences》 2025年第4期747-766,共20页
In contemporary geotechnical projects,various approaches are employed for forecasting the settlement of shallow foundations(S_(m)).However,achieving precise modeling of foundation behavior using certain techniques(suc... In contemporary geotechnical projects,various approaches are employed for forecasting the settlement of shallow foundations(S_(m)).However,achieving precise modeling of foundation behavior using certain techniques(such as analytical,numerical,and regression)is challenging and sometimes unattainable.This is primarily due to the inherent nonlinearity of the model,the intricate nature of geotechnical materials,the complex interaction between soil and foundation,and the inherent uncertainty in soil parameters.Therefore,thesemethods often introduce assumptions and simplifications,resulting in relationships that deviate from the actual problem’s reality.In addition,many of these methods demand significant investments of time and resources but neglect to account for the uncertainty inherent in soil/rock parameters.This study explores the application of innovative intelligent techniques to predict S_(m) to address these shortcomings.Specifically,two optimization algorithms,namely teaching-learning-based optimization(TLBO)and harmony search(HS),are harnessed for this purpose.The modeling process involves utilizing input parameters,such as thewidth of the footing(B),the pressure exerted on the footing(q),the count of SPT(Standard Penetration Test)blows(N),the ratio of footing embedment(Df/B),and the footing’s geometry(L/B),during the training phase with a dataset comprising 151 data points.Then,the models’accuracy is assessed during the testing phase using statistical metrics,including the coefficient of determination(R^(2)),mean square error(MSE),and rootmean square error(RMSE),based on a dataset of 38 data points.The findings of this investigation underscore the substantial efficacy of intelligent optimization algorithms as valuable tools for geotechnical engineers when estimating S_(m).In addition,a sensitivity analysis of the input parameters in S_(m) estimation is conducted using@RISK software,revealing that among the various input parameters,the N exerts the most pronounced influence on S_(m). 展开更多
关键词 Shallow foundations optimization algorithms settlement prediction intelligent methods sensitivity analysis
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