Installing internal bulkheads in a composite bucket foundation alters the rotational symmetry characteristic of a single-compartment bucket foundation,consequently influencing the stress distribution within the bucket...Installing internal bulkheads in a composite bucket foundation alters the rotational symmetry characteristic of a single-compartment bucket foundation,consequently influencing the stress distribution within the bucket and surrounding soil.During the seabed penetration of a spudcan from a jack-up wind turbine installation vessel,an angle may form between the spudcan’s axis and the axis of symmetry of the adjacent composite bucket foundation in the horizontal plane.Such a misalignment may affect load distribution and the non-uniform interaction between the foundation,soil,and spudcan,ultimately influencing the foundation’s stability.This study employs physical model tests to ascertain the trends in end resistance during spudcan penetration in sand,the extent of soil disturbance,and the backflow condition.The finite element coupled Eulerian-Lagrangian method is validated and utilized to determine the range of penetration angles that induce alterations in the maximum vertical displacement and tilt rate of the composite bucket foundation in sand.The differential contact stress distribution at the base of the bucket is analyzed,with qualitative criteria for sand backflow provided.Findings demonstrate that the maximum vertical displacement and tilt rate of the composite bucket foundation display a“wave-like”variation with the increasing spudcan penetration angle,peaking when the angle between the spudcan and bulkhead is the smallest.Stress distribution is predominantly concentrated at the base and apex of the bucket,becoming increasingly uneven as the penetration angle deviates from the foundation’s symmetry axis.The maximum stress gradually shifts to the junction of the bulkhead and bucket bottom on the side with the shortest net distance from the spudcan.Considering the in-place stability and stress state of the composite bucket foundation is therefore imperative,and particular attention should be paid to the foundation’s state when the angle between the spudcan and bulkhead is small.展开更多
High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging ...High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging foundation models and multimodal learning frameworks are enabling scalable and transferable representations of cellular states,while advances in interpretability and real-world data integration are bridging the gap between discovery and clinical application.This paper outlines a concise roadmap for AI-driven,transcriptome-centered multi-omics integration in precision medicine(Figure 1).展开更多
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
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
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
This paper proposes a longitudinal vulnerability-based analysis method to evaluate the impact of foundation pit excavation on shield tunnels,accounting for geological uncertainties.First,the shield tunnel is modeled a...This paper proposes a longitudinal vulnerability-based analysis method to evaluate the impact of foundation pit excavation on shield tunnels,accounting for geological uncertainties.First,the shield tunnel is modeled as an Euler Bernoulli beam resting on the Pasternak foundation incorporating variability in subgrade parameters along the tunnel’s length.A random analysis method using random field theory is introduced to evaluate the tunnel’s longitudinal responses to excavation.Next,a risk assessment index system is established.The normalized relative depth between the excavation and the shield tunnel is used as a risk index,while the maximum longitudinal deformation,the maximum circumferential opening,and the maximum longitudinal bending moment serve as performance indicators.Based on these,a method for analyzing the longitudinal fragility of shield tunnels under excavation-induced disturbances is proposed.Finally,the technique is applied to a case study involving a foundation pit excavation above a shield tunnel,which is the primary application scenario of this method.Vulnerability curves for different performance indicators are derived,and the effects of tunnel stiffness and subgrade stiffness on the tunnel vulnerability are explored.The results reveal significant differences in vulnerability curves depending on the performance index used.Compared to the maximum circumferential opening and the maximum longitudinal bending moment,selecting the maximum longitudinal deformation as the control index better ensures the tunnel’s usability and safety under excavation disturbances.The longitudinal vulnerability of the shield tunnel nonlinearly decreases with the increase of the tunnel stiffness and subgrade stiffness,and the subgrade stiffness has a more pronounced effect.Parametric analyses suggest that actively reinforcing the substratum is more effective on reducing the risk of tunnel failure due to adjacent excavations than passive reinforcement of the tunnel structure.展开更多
At the invitation of the Friedrich Ebert Foundation(Friedrich-Ebert-Stiftung),the Thai-Chinese Culture and Economy Association and the Viet Nam Union of Friendship Organisations,a CAFIU delegation headed by President ...At the invitation of the Friedrich Ebert Foundation(Friedrich-Ebert-Stiftung),the Thai-Chinese Culture and Economy Association and the Viet Nam Union of Friendship Organisations,a CAFIU delegation headed by President Ji Bingxuan,also Vice-Chairperson of the Standing Committee of the 13th National People's Congress of China visited Germany,Thailand and Vietnam from 26 November to 5 December 2024.展开更多
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
Gastrointestinal(GI)cancers represent a major global health concern due to their high incidence and mortality rates.Foundation models(FMs),also referred to as large models,represent a novel class of artificial intelli...Gastrointestinal(GI)cancers represent a major global health concern due to their high incidence and mortality rates.Foundation models(FMs),also referred to as large models,represent a novel class of artificial intelligence technologies that have demonstrated considerable potential in addressing these challenges.These models encompass large language models(LLMs),vision FMs(VFMs),and multimodal LLMs(MLLMs),all of which utilize transformer architectures and self-supervised pre-training on extensive unlabeled datasets to achieve robust cross-domain generalization.This review delineates the principal applications of these models:LLMs facilitate the structuring of clinical narratives,extraction of insights from medical records,and enhancement of physician-patient communication;VFMs are employed in the analysis of endoscopic,radiological,and pathological images for lesion detection and staging;MLLMs integrate heterogeneous data modalities,including imaging,textual information,and genomic data,to support diagnostic processes,treatment prediction,and prognostic evaluation.Despite these promising developments,several challenges remain,such as the need for data standardization,limited diversity within training datasets,substantial computational resource requirements,and ethical-legal concerns.In conclusion,FMs exhibit significant potential to advance research and clinical management of GI cancers.Future research efforts should prioritize the refinement of these models,promote international collaborations,and adopt interdisciplinary approaches.Such a comprehensive strategy is essential to fully harness the capabilities of FMs,driving substantial progress in the fight against GI malignancies.展开更多
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
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
This work investigates the indentation response of an elastic plate resting upon a thin,transversely isotropic elastic layer supported by a rigid substrate.Such a scenario is encountered across a range of length scale...This work investigates the indentation response of an elastic plate resting upon a thin,transversely isotropic elastic layer supported by a rigid substrate.Such a scenario is encountered across a range of length scales from piezoresistive tests on graphite nanoflakes to the bending of floating ice shelves atop seabed,where the elastic layer commonly exhibits certain anisotropy.We first develop an approximate model to describe the elastic response of a transversely isotropic layer by exploiting the slenderness of the layer.We show that this approximate model can be reduced to the classic compressible Winkler foundation model as the elastic constants of the layer are set isotropic.We then investigate the combined response of an elastic plate on the transversely isotropic elastic layer.Facilitated by the simplicity of our proposed approximate model,we can derive simple analytical solutions for the cases of small and large indenter radi.The analytical results agree well with numerical calculations obtained via finite element methods,as long as the system is sufficiently slender in a mechanical sense.These results offer quantitative insights into the mechanical behavior of numerous semiconductor materials characterized by transverse isotropy and employed with slender geometries in various practical applications where the thin layer works as conductive and functional layers.展开更多
This paper proposes a zero-shot based spatial recognition AI algorithm by fusing and developing multidimensional vision identification technology adapted to the situation in large indoor and underground spaces.With th...This paper proposes a zero-shot based spatial recognition AI algorithm by fusing and developing multidimensional vision identification technology adapted to the situation in large indoor and underground spaces.With the expansion of large shopping malls and underground urban spaces(UUS),there is an increasing need for new technologies that can quickly identify complex indoor structures and changes such as relocation,remodeling,and construction for the safety and management of citizens through the provision of the up-to-date indoor 3D site maps.The proposed algorithm utilizes data collected by an unmanned robot to create a 3D site map of the up-to-date indoor site and recognizes complex indoor spaces based on zero-shot learning.This research specifically addresses two major challenges:the difficulty of detecting walls and floors due to complex patterns and the difficulty of spatial perception due to unknown obstacles.The proposed algorithm addresses the limitations of the existing foundation model,detects floors and obstacles without expensive sensors,and improves the accuracy of spatial recognition by combining floor detection,vanishing point detection,and fusion obstacle detection algorithms.The experimental results show that the algorithm effectively detects the floor and obstacles in various indoor environments,with F1 scores of 0.96 and 0.93 in the floor detection and obstacle detection experiments,respectively.展开更多
Drains play an important role in seepage control in geotechnical engineering.The enormous number and one-dimensional(1D)geometry of drainage holes make their nature difficult to be accurately modeled in groundwater fl...Drains play an important role in seepage control in geotechnical engineering.The enormous number and one-dimensional(1D)geometry of drainage holes make their nature difficult to be accurately modeled in groundwater flow simulation.It has been well understood that drains function by presenting discharge boundaries,which can be characterized by water head,no-flux,unilateral or mixed water head-unilateral boundary condition.It has been found after years of practices that the flow simulation may become erroneous if the transitions among the drain boundary conditions are not properly considered.For this,a rigorous algorithm is proposed in this study to detect the onset of transitions among the water head,noflux and mixed water head-unilateral boundary conditions for downwards-drilled drainage holes,which theoretically completes the description of drain boundary conditions.After verification against a numerical example,the proposed algorithm is applied to numerical modeling of groundwater flow through a gravity dam foundation.The simulation shows that for hundreds of downwards-drilled drainage holes used to be prescribed with water head boundary condition,56%and 2%of them are transitioned to mixed water head-unilateral and no-flux boundary conditions,respectively.The phreatic surface around the drains will be overestimated by 25e33 m without the use of the mixed boundary condition.For the first time,this study underscores the importance of the mixed water head-unilateral boundary condition and the proposed transition algorithm in drain modeling,which may become more essential for simulation of transient flow because of groundwater dynamics.展开更多
Plasma Science and Technology(PST)journal assists in advancing plasma science and technology by reporting important,novel,helpful and thought-provoking progress in this strongly multidisciplinary and interdisciplinary...Plasma Science and Technology(PST)journal assists in advancing plasma science and technology by reporting important,novel,helpful and thought-provoking progress in this strongly multidisciplinary and interdisciplinary field,in a timely manner.This field encompasses foundational plasma phenomena;low-temperature plasmas;magnetically confined plasmas;inertially confined plasmas;astrophysics and space plasmas;and interdisciplinary science of these;and the engineering and technology development and application from them.PST is sponsored jointly by the Institute of Plasma Physics of the Chinese Academy of Sciences,and the Chinese Society of Theoretical and Applied Mechanics.The joumal joined the Science Ciation Index in 2003,the Engineering Index in 2006,and became published online by IOP Publishing Ltd.in 2006.展开更多
Dr.Leon van Paassen has been selected as the winner for the Distinguished 2025 Biogeotechnics Lecture Award.Leon van Paassen is an expert on biogeotechnics with more than 20 years of experience in academia and industr...Dr.Leon van Paassen has been selected as the winner for the Distinguished 2025 Biogeotechnics Lecture Award.Leon van Paassen is an expert on biogeotechnics with more than 20 years of experience in academia and industry.He graduated as an Engineering Geologist at Delft University of Technology in 2002.After graduation,he performed foundation inspections and vibration monitoring at IFCO foundations and worked as a consultant and researcher at GeoDelft which later became Deltares.展开更多
Uplift of segmental linings in shield tunnels presents considerable challenges,potentially compromising the structural integrity of tunnels.The uplift movement can be physically modelled using a Timoshenko beam on a W...Uplift of segmental linings in shield tunnels presents considerable challenges,potentially compromising the structural integrity of tunnels.The uplift movement can be physically modelled using a Timoshenko beam on a Winkler foundation.This study introduces an innovative method employing a physicsinformed neural network(PINN)to solve the governing differential equations of shield tunnel linings under specifiedboundary conditions,known loads,and foundation parameters.Importantly,the PINN does not rely on empirical data for training;instead,it incorporates physics-based constraints to accurately capture spatial variations in load and foundation stiffness during grouting and construction phases.The PINN model was validated with fielddata from a shield tunnel in the Pazhou branch of the Guangzhou-Dongguan-Shenzhen intercity railway line.The results demonstrate the effectiveness of the model in predicting segment uplift.Furthermore,compared to traditional analytical solutions,the PINN model provides a more realistic representation of fieldconditions by integrating spatial variations in loading and foundation support.展开更多
On April 23rd,China Association for NGO Cooperation(CANGO)sent representatives to attend the International Symposium on Humanism for the Future:Ontopsychology and Education for the Formation of Responsible and Autonom...On April 23rd,China Association for NGO Cooperation(CANGO)sent representatives to attend the International Symposium on Humanism for the Future:Ontopsychology and Education for the Formation of Responsible and Autonomous Individuals held at the headquarters of UNEsCO in Paris,and celebrated the 15th Anniversary of the Antonio Meneghetti Foundation.展开更多
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
Plasma Science and Technology (PST) journal assists in advancing plasma science and technology by reporting important,novel,helpful and thought-provoking progress in this strongly multidisciplinary and interdisciplina...Plasma Science and Technology (PST) journal assists in advancing plasma science and technology by reporting important,novel,helpful and thought-provoking progress in this strongly multidisciplinary and interdisciplinary field,in a timely manner.This field encompasses foundational plasma phenomena;low-temperature plasmas;magnetically confined plasmas;inertially confined plasmas;astrophysics and space plasmas;and interdisciplinary science of these;and the engineering and technology development and application from them.展开更多
文摘Installing internal bulkheads in a composite bucket foundation alters the rotational symmetry characteristic of a single-compartment bucket foundation,consequently influencing the stress distribution within the bucket and surrounding soil.During the seabed penetration of a spudcan from a jack-up wind turbine installation vessel,an angle may form between the spudcan’s axis and the axis of symmetry of the adjacent composite bucket foundation in the horizontal plane.Such a misalignment may affect load distribution and the non-uniform interaction between the foundation,soil,and spudcan,ultimately influencing the foundation’s stability.This study employs physical model tests to ascertain the trends in end resistance during spudcan penetration in sand,the extent of soil disturbance,and the backflow condition.The finite element coupled Eulerian-Lagrangian method is validated and utilized to determine the range of penetration angles that induce alterations in the maximum vertical displacement and tilt rate of the composite bucket foundation in sand.The differential contact stress distribution at the base of the bucket is analyzed,with qualitative criteria for sand backflow provided.Findings demonstrate that the maximum vertical displacement and tilt rate of the composite bucket foundation display a“wave-like”variation with the increasing spudcan penetration angle,peaking when the angle between the spudcan and bulkhead is the smallest.Stress distribution is predominantly concentrated at the base and apex of the bucket,becoming increasingly uneven as the penetration angle deviates from the foundation’s symmetry axis.The maximum stress gradually shifts to the junction of the bulkhead and bucket bottom on the side with the shortest net distance from the spudcan.Considering the in-place stability and stress state of the composite bucket foundation is therefore imperative,and particular attention should be paid to the foundation’s state when the angle between the spudcan and bulkhead is small.
文摘High-throughput transcriptomics has evolved from bulk RNA-seq to single-cell and spatial profiling,yet its clinical translation still depends on effective integration across diverse omics and data modalities.Emerging foundation models and multimodal learning frameworks are enabling scalable and transferable representations of cellular states,while advances in interpretability and real-world data integration are bridging the gap between discovery and clinical application.This paper outlines a concise roadmap for AI-driven,transcriptome-centered multi-omics integration in precision medicine(Figure 1).
基金supported by the National Natural Science Foundation of China(62225302,623B2014,and 62173023).
文摘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.
文摘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.
基金Projects(52008403,52378421)supported by the National Natural Science Foundation of ChinaProject(2022-Key-10)supported by the Science and Technology Research and Development Program Project of China Railway Group LimitedProject(202207)supported by the Hunan Provincial Transportation Science and Technology,China。
文摘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.
基金Project(52178402) supported by the National Natural Science Foundation of China。
文摘This paper proposes a longitudinal vulnerability-based analysis method to evaluate the impact of foundation pit excavation on shield tunnels,accounting for geological uncertainties.First,the shield tunnel is modeled as an Euler Bernoulli beam resting on the Pasternak foundation incorporating variability in subgrade parameters along the tunnel’s length.A random analysis method using random field theory is introduced to evaluate the tunnel’s longitudinal responses to excavation.Next,a risk assessment index system is established.The normalized relative depth between the excavation and the shield tunnel is used as a risk index,while the maximum longitudinal deformation,the maximum circumferential opening,and the maximum longitudinal bending moment serve as performance indicators.Based on these,a method for analyzing the longitudinal fragility of shield tunnels under excavation-induced disturbances is proposed.Finally,the technique is applied to a case study involving a foundation pit excavation above a shield tunnel,which is the primary application scenario of this method.Vulnerability curves for different performance indicators are derived,and the effects of tunnel stiffness and subgrade stiffness on the tunnel vulnerability are explored.The results reveal significant differences in vulnerability curves depending on the performance index used.Compared to the maximum circumferential opening and the maximum longitudinal bending moment,selecting the maximum longitudinal deformation as the control index better ensures the tunnel’s usability and safety under excavation disturbances.The longitudinal vulnerability of the shield tunnel nonlinearly decreases with the increase of the tunnel stiffness and subgrade stiffness,and the subgrade stiffness has a more pronounced effect.Parametric analyses suggest that actively reinforcing the substratum is more effective on reducing the risk of tunnel failure due to adjacent excavations than passive reinforcement of the tunnel structure.
文摘At the invitation of the Friedrich Ebert Foundation(Friedrich-Ebert-Stiftung),the Thai-Chinese Culture and Economy Association and the Viet Nam Union of Friendship Organisations,a CAFIU delegation headed by President Ji Bingxuan,also Vice-Chairperson of the Standing Committee of the 13th National People's Congress of China visited Germany,Thailand and Vietnam from 26 November to 5 December 2024.
文摘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.
基金Supported by the Open Project Program of Panxi Crops Research and Utilization Key Laboratory of Sichuan Province,No.SZKF202302the Fundamental Research Funds for the Central Universities No.2019CDYGYB024.
文摘Gastrointestinal(GI)cancers represent a major global health concern due to their high incidence and mortality rates.Foundation models(FMs),also referred to as large models,represent a novel class of artificial intelligence technologies that have demonstrated considerable potential in addressing these challenges.These models encompass large language models(LLMs),vision FMs(VFMs),and multimodal LLMs(MLLMs),all of which utilize transformer architectures and self-supervised pre-training on extensive unlabeled datasets to achieve robust cross-domain generalization.This review delineates the principal applications of these models:LLMs facilitate the structuring of clinical narratives,extraction of insights from medical records,and enhancement of physician-patient communication;VFMs are employed in the analysis of endoscopic,radiological,and pathological images for lesion detection and staging;MLLMs integrate heterogeneous data modalities,including imaging,textual information,and genomic data,to support diagnostic processes,treatment prediction,and prognostic evaluation.Despite these promising developments,several challenges remain,such as the need for data standardization,limited diversity within training datasets,substantial computational resource requirements,and ethical-legal concerns.In conclusion,FMs exhibit significant potential to advance research and clinical management of GI cancers.Future research efforts should prioritize the refinement of these models,promote international collaborations,and adopt interdisciplinary approaches.Such a comprehensive strategy is essential to fully harness the capabilities of FMs,driving substantial progress in the fight against GI malignancies.
文摘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.
文摘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.
基金supported by the National Natural Science Foundation of China(12372103)the Opening Fund of State Key Laboratory of Nonlinear Mechanics(Institute of Mechanics,CAS)the Fundamental Research Funds for Central Universities(Peking University).
文摘This work investigates the indentation response of an elastic plate resting upon a thin,transversely isotropic elastic layer supported by a rigid substrate.Such a scenario is encountered across a range of length scales from piezoresistive tests on graphite nanoflakes to the bending of floating ice shelves atop seabed,where the elastic layer commonly exhibits certain anisotropy.We first develop an approximate model to describe the elastic response of a transversely isotropic layer by exploiting the slenderness of the layer.We show that this approximate model can be reduced to the classic compressible Winkler foundation model as the elastic constants of the layer are set isotropic.We then investigate the combined response of an elastic plate on the transversely isotropic elastic layer.Facilitated by the simplicity of our proposed approximate model,we can derive simple analytical solutions for the cases of small and large indenter radi.The analytical results agree well with numerical calculations obtained via finite element methods,as long as the system is sufficiently slender in a mechanical sense.These results offer quantitative insights into the mechanical behavior of numerous semiconductor materials characterized by transverse isotropy and employed with slender geometries in various practical applications where the thin layer works as conductive and functional layers.
基金supported by Kyonggi University Research Grant 2024.
文摘This paper proposes a zero-shot based spatial recognition AI algorithm by fusing and developing multidimensional vision identification technology adapted to the situation in large indoor and underground spaces.With the expansion of large shopping malls and underground urban spaces(UUS),there is an increasing need for new technologies that can quickly identify complex indoor structures and changes such as relocation,remodeling,and construction for the safety and management of citizens through the provision of the up-to-date indoor 3D site maps.The proposed algorithm utilizes data collected by an unmanned robot to create a 3D site map of the up-to-date indoor site and recognizes complex indoor spaces based on zero-shot learning.This research specifically addresses two major challenges:the difficulty of detecting walls and floors due to complex patterns and the difficulty of spatial perception due to unknown obstacles.The proposed algorithm addresses the limitations of the existing foundation model,detects floors and obstacles without expensive sensors,and improves the accuracy of spatial recognition by combining floor detection,vanishing point detection,and fusion obstacle detection algorithms.The experimental results show that the algorithm effectively detects the floor and obstacles in various indoor environments,with F1 scores of 0.96 and 0.93 in the floor detection and obstacle detection experiments,respectively.
基金Financial support from the National Natural Science Foundation of China(Grant Nos.51925906 and U2340228)the Natural Science Foundation of Hubei Province(Grant No.2022CFA028)is acknowledged.
文摘Drains play an important role in seepage control in geotechnical engineering.The enormous number and one-dimensional(1D)geometry of drainage holes make their nature difficult to be accurately modeled in groundwater flow simulation.It has been well understood that drains function by presenting discharge boundaries,which can be characterized by water head,no-flux,unilateral or mixed water head-unilateral boundary condition.It has been found after years of practices that the flow simulation may become erroneous if the transitions among the drain boundary conditions are not properly considered.For this,a rigorous algorithm is proposed in this study to detect the onset of transitions among the water head,noflux and mixed water head-unilateral boundary conditions for downwards-drilled drainage holes,which theoretically completes the description of drain boundary conditions.After verification against a numerical example,the proposed algorithm is applied to numerical modeling of groundwater flow through a gravity dam foundation.The simulation shows that for hundreds of downwards-drilled drainage holes used to be prescribed with water head boundary condition,56%and 2%of them are transitioned to mixed water head-unilateral and no-flux boundary conditions,respectively.The phreatic surface around the drains will be overestimated by 25e33 m without the use of the mixed boundary condition.For the first time,this study underscores the importance of the mixed water head-unilateral boundary condition and the proposed transition algorithm in drain modeling,which may become more essential for simulation of transient flow because of groundwater dynamics.
文摘Plasma Science and Technology(PST)journal assists in advancing plasma science and technology by reporting important,novel,helpful and thought-provoking progress in this strongly multidisciplinary and interdisciplinary field,in a timely manner.This field encompasses foundational plasma phenomena;low-temperature plasmas;magnetically confined plasmas;inertially confined plasmas;astrophysics and space plasmas;and interdisciplinary science of these;and the engineering and technology development and application from them.PST is sponsored jointly by the Institute of Plasma Physics of the Chinese Academy of Sciences,and the Chinese Society of Theoretical and Applied Mechanics.The joumal joined the Science Ciation Index in 2003,the Engineering Index in 2006,and became published online by IOP Publishing Ltd.in 2006.
文摘Dr.Leon van Paassen has been selected as the winner for the Distinguished 2025 Biogeotechnics Lecture Award.Leon van Paassen is an expert on biogeotechnics with more than 20 years of experience in academia and industry.He graduated as an Engineering Geologist at Delft University of Technology in 2002.After graduation,he performed foundation inspections and vibration monitoring at IFCO foundations and worked as a consultant and researcher at GeoDelft which later became Deltares.
基金funded by“The Pearl River Talent Recruitment Program”in 2019(Grant No.2019CX01G338)Guangdong Province and Guangdong Provincial Basic and Applied Basic Research Fund Committee(2022A1515240073).
文摘Uplift of segmental linings in shield tunnels presents considerable challenges,potentially compromising the structural integrity of tunnels.The uplift movement can be physically modelled using a Timoshenko beam on a Winkler foundation.This study introduces an innovative method employing a physicsinformed neural network(PINN)to solve the governing differential equations of shield tunnel linings under specifiedboundary conditions,known loads,and foundation parameters.Importantly,the PINN does not rely on empirical data for training;instead,it incorporates physics-based constraints to accurately capture spatial variations in load and foundation stiffness during grouting and construction phases.The PINN model was validated with fielddata from a shield tunnel in the Pazhou branch of the Guangzhou-Dongguan-Shenzhen intercity railway line.The results demonstrate the effectiveness of the model in predicting segment uplift.Furthermore,compared to traditional analytical solutions,the PINN model provides a more realistic representation of fieldconditions by integrating spatial variations in loading and foundation support.
文摘On April 23rd,China Association for NGO Cooperation(CANGO)sent representatives to attend the International Symposium on Humanism for the Future:Ontopsychology and Education for the Formation of Responsible and Autonomous Individuals held at the headquarters of UNEsCO in Paris,and celebrated the 15th Anniversary of the Antonio Meneghetti Foundation.
基金jointly sponsored by Fujian Province construction science and technology development research project(2023-B-07,2023-K-47,2022-K-118)。
文摘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.
文摘Plasma Science and Technology (PST) journal assists in advancing plasma science and technology by reporting important,novel,helpful and thought-provoking progress in this strongly multidisciplinary and interdisciplinary field,in a timely manner.This field encompasses foundational plasma phenomena;low-temperature plasmas;magnetically confined plasmas;inertially confined plasmas;astrophysics and space plasmas;and interdisciplinary science of these;and the engineering and technology development and application from them.
