A higher order boundary dement method (HOBEM) is implemented for wave-current action on structures. The freeterm coefficient and Cauchy principal value ( GPV) integrals are computed by direct methods. Numerical ex...A higher order boundary dement method (HOBEM) is implemented for wave-current action on structures. The freeterm coefficient and Cauchy principal value ( GPV) integrals are computed by direct methods. Numerical experiments are carried out to validate the computation of free-term coefficient and GPV integrals. The results show that the computation precision of free-term coefficient is very high for various bodies, even with edges and corners, and the convergence speed is fast for CPV integrals for different meshes. The comparison of the second order mean drift force due to wave-current action on a uniform cylinder is made with an analytic solution. It is found that good agreement exists between the present calculation and the analytic solutions. Finally, the numerical code is applied for computing wave-current action on Snorrc TLP.展开更多
Studies of wave-current interactions are vital for the safe design of structures.Regular waves in the presence of uniform,linear shear,and quadratic shear currents are explored by the High-Level Green-Naghdi model in ...Studies of wave-current interactions are vital for the safe design of structures.Regular waves in the presence of uniform,linear shear,and quadratic shear currents are explored by the High-Level Green-Naghdi model in this paper.The five-point central difference method is used for spatial discretization,and the fourth-order Adams predictor-corrector scheme is employed for marching in time.The domain-decomposition method is applied for the wave-current generation and absorption.The effects of currents on the wave profile and velocity field are examined under two conditions:the same velocity of currents at the still-water level and the constant flow volume of currents.Wave profiles and velocity fields demonstrate substantial differences in three types of currents owing to the diverse vertical distribution of current velocity and vorticity.Then,loads on small-scale vertical cylinders subjected to regular waves and three types of background currents with the same flow volume are investigated.The maximum load intensity and load fluctuation amplitude in uniform,linear shear,and quadratic shear currents increase sequentially.The stretched superposition method overestimates the maximum load intensity and load fluctuation amplitude in opposing currents and underestimates these values in following currents.The stretched superposition method obtains a poor approximation for strong nonlinear waves,particularly in the case of the opposing quadratic shear current.展开更多
Under the combination of currents and waves, seabed scour occurs around offshore wind turbine foundations, which affects the stability and safe operation of offshore wind turbines. In this study, physical model experi...Under the combination of currents and waves, seabed scour occurs around offshore wind turbine foundations, which affects the stability and safe operation of offshore wind turbines. In this study, physical model experiments under unidirectional flow, bidirectional flow, and wave-current interactions with different flow directions around the pile group foundation were first conducted to investigate the development of scour around the pile group foundation.Additionally, a three-dimensional scour numerical model was established via the open-source software REEF3D to simulate the flow field and scour around the prototype-scale foundation. The impact of flow on scour was discussed.Under unidirectional flow, scour equilibrium was reached more quickly, with the maximum scour depth reaching approximately 1.2 times the pile diameter and the extent of the scour hole spanning about 4.9 times the pile diameter.Compared with those under unidirectional flow, the scour depths under combinations of currents and waves, as well as bidirectional flow, were slightly smaller. However, the morphology of scour holes was more uniform and symmetrical. The numerical simulation results show good agreement with the experimental data, demonstrating the impact of varying flow directions on the velocity distribution around the foundation, the morphology of scour holes, and the location of the maximum scour depth.展开更多
The movement of sediment in estuary and on coast is directly restricted by the bed shear stress. Therefore, the research on the basic problem of sediment movement by the bed shear stress is an important way to researc...The movement of sediment in estuary and on coast is directly restricted by the bed shear stress. Therefore, the research on the basic problem of sediment movement by the bed shear stress is an important way to research the theory of sediment movement. However, there is not a measuring and computing method to measure the bed shear stress under a complicated dynamic effect like wave and current. This paper describes the measurement and test research on the bed shear stress in a long launder of direct current by the new instrument named thermal shearometer based on micro-nanotechnology. As shown by the research results, the thermal shearometer has a high response frequency and strong stability. The measured results can reflect the basic change of the bed shear stress under wave and wave-current effect, and confirm that the method of measuring bed shear stress under wave-current effect with thermal shearometer is feasible. Meanwhile, a preliminary method to compute the shear stress compounded by wave-current is put forward according to the tested and measured results, and then a reference for further study on the basic theory of sediment movement under a complicated dynamic effect is provided.展开更多
The interaction between waves, currents and bottoms in estuarine and coastal regions is ubiquitious, in particular the dynamic mechanism of waves on large-scale slowly varying currents. The wave action concept may be ...The interaction between waves, currents and bottoms in estuarine and coastal regions is ubiquitious, in particular the dynamic mechanism of waves on large-scale slowly varying currents. The wave action concept may be extended and applicated to the study of the mechanism. Considering the effects of moving bottoms and starting from the Navier-Stokes equation of motion of a vinous fluid including the Coriolis force, a generalized mean-flow medel theory for the nearshore region, that is, a set of mean-flow equations and their generalized wave action equation involving the three new kinds of actions termed respectively as the current wave action, the bottom wave action and the dissipative wave action which can be applied to arbitrary depth over moving bottoms and ambient currents with a typical vertical structure, is developed by vertical integration and time-averaglng over a wave peried, thus extending the classical concept, wave action, from the ideal averaged flow conservative system to the real averaged flow dissipative dynamical system, and having a large range of application.展开更多
Wave-current interaction and its effects on the hydrodynamic environment in the Beibu Gulf(BG) have been investigated via employing the Coupled Ocean–Atmosphere–Wave–Sediment Transport(COAWST) modeling system. The ...Wave-current interaction and its effects on the hydrodynamic environment in the Beibu Gulf(BG) have been investigated via employing the Coupled Ocean–Atmosphere–Wave–Sediment Transport(COAWST) modeling system. The model could simulate reasonable hydrodynamics in the BG when validated by various observations.Vigorous tidal currents refract the waves efficiently and make the seas off the west coast of Hainan Island be the hot spot where currents modulate the significant wave height dramatically. During summer, wave-enhanced bottom stress could weaken the near-shore component of the gulf-scale cyclonic-circulation in the BG remarkably, inducing two major corresponding adjustments: Model results reveal that the deep-layer cold water from the southern BG makes critical contribution to maintaining the cold-water mass in the northern BG Basin.However, the weakened background circulation leads to less cold water transported from the southern gulf to the northern gulf, which finally triggers a 0.2℃ warming in the cold-water mass area;In the top areas of the BG, the suppressed background circulation reduces the transport of the diluted water to the central gulf. Therefore, more freshwater could be trapped locally, which then triggers lower sea surface salinity(SSS) in the near-field and higher SSS in the far-field.展开更多
The northern South China Sea(SCS) is frequently affected by typhoons. During severe storm events, wave-current interactions produce storm surges causing enormous damage in the path of the typhoon. To evaluate the infl...The northern South China Sea(SCS) is frequently affected by typhoons. During severe storm events, wave-current interactions produce storm surges causing enormous damage in the path of the typhoon. To evaluate the influence of wave-current interactions on storm surge, we used a coupled ocean-atmospherewave-sediment transport(COAWST) modeling system with radiation-stress and vortex-force formulations to simulate two typically intense tropical storms that invaded the SCS, namely Typhoons Nuri(2008) and Hagupit(2008), and compared results with observations from the Hong Kong Observatory. Both radiationstress and vortex-force formulations significantly improved the accuracy of the simulation. Depending on which typhoon and the topography encountered, the influence of surface waves on the oceanic circulation showed different characteristics, including the differences of range and intensity of storm surge between vortex-force and radiation-stress experiments. During typhoon landing, strong sea-surface elevation in concert with wave set-up/set-down caused the adjustment of the momentum balance. In the direction perpendicular to the current, but especially in the cross-shore direction, the pressure gradient and wave effects on the current dominated the momentum balance.展开更多
We examined the influences of the wind fi eld and wave-current interaction(WCI)on the numerical simulation results of typhoon-induced wind waves in the northern East China Sea(NECS)using the coupled Simulating Waves N...We examined the influences of the wind fi eld and wave-current interaction(WCI)on the numerical simulation results of typhoon-induced wind waves in the northern East China Sea(NECS)using the coupled Simulating Waves Nearshore+Advanced Circulation(SWAN+ADCIRC)model.The simulations were performed during two typhoon events(Lekima and Muifa),and two widely used reanalysis wind fields,the Climate Forecast System Version 2(CFSv2)from the National Centers for Environmental Prediction(NCEP)and the fifth-generation European Centre for Medium-Range Weather Forecasts(ECMWF)Reanalysis(ERA5),were compared.The results indicate that the ERA5 and CFSv2 wind fields both reliably reproduced the wind variations measured by in-situ buoys,and the accuracy of the winds from ERA5 were generally better than those from CFSv2 because CFSv2 tended to overestimate the wind speed and the simulated significant wave height(SWH),particularly the peak SWH.The WCI effects between the two wind field simulations were similar;these effects enhanced the SWH throughout the nearshore NECS during both typhoons but suppressed the SWH on the right side of the Typhoon Muifa track in the deep and off shore sea areas.In summary,variations in the water depth and current propagation direction dominate the modulation of wave height.展开更多
The nonlinear dynamic response induced by the wave-current interaction on a deepwater steep wave riser(SWR)is numerically investigated based on a three-dimensional(3 D)time-domain finite element method(FEM).The govern...The nonlinear dynamic response induced by the wave-current interaction on a deepwater steep wave riser(SWR)is numerically investigated based on a three-dimensional(3 D)time-domain finite element method(FEM).The governing equation considering internal flow is established in the global coordinate system.The whole SWR consists of three segments:the decline segment,buoyancy segment and hang-off segment,in which the buoyancy segment is wrapped by several buoyancy modules in the middle section,leading to the arch bend and sag bend.A Newmark-β iterative scheme is adopted for the accurate analysis to solve the governing equation and update the dynamic response at each time step.The proposed method is verified through the published results for the dynamic response of steel catenary riser(SCR)and static configuration of steel lazy wave riser(SLWR).Simulations are executed to study the influence of wave height,current velocity/direction,internal flow density/velocity and top-end pressure on the tension,configuration and bending moment of the SWR.The results indicate that the influence of the current on the configuration and mechanical behavior of the SWR is greater than that of the wave,especially in the middle section.With increasing current velocity,the suspending height of the middle section drops,meanwhile,its bending moment decreases accordingly,but the tension increases significantly.For a fixed external load,the increasing internal flow density induces the amplification of the tension at the hang-off segment and the mitigation at the decline segment,while the opposite trend occurs at the bending moment.展开更多
The aim of this paper is to present an analytical expression for the streamwise velocity distribution in a non-uniform flow in the presence of waves; the correlation between the horizontal and vertical velocity compon...The aim of this paper is to present an analytical expression for the streamwise velocity distribution in a non-uniform flow in the presence of waves; the correlation between the horizontal and vertical velocity components has been compreheusively examined. Different from previous researches which attributed the deviation of velocity from the classical log-law to the wave Reynolds stress, i.e. - ρ uv^- only, this study demonstrates that the momentum flux caused by mean velocities, i.e., u^- and v^-, is also responsible for the velocity deviation, and it is found that the streamwise velocity for a flow in the presence of non-zero wall-normal velocity does not follow the classical log-law, but the modified log-law proposed in this study based on simplified mixing-length theorem. The validity of the modified log-law has been verified by use of available experimental data from published sources for combined wave-current flows, and good agreement between the predicted and observed velocity profiles has been achieved.展开更多
The combination of Daphnes Cortex(DC)and Liquorice Root(LR),two traditional Chinese medicinal herbs,has shown significant therapeutic effects on rheumatoid arthritis(RA),but its synergistic mechanism of action remains...The combination of Daphnes Cortex(DC)and Liquorice Root(LR),two traditional Chinese medicinal herbs,has shown significant therapeutic effects on rheumatoid arthritis(RA),but its synergistic mechanism of action remains to be elucidated.Employing a network pharmacology and molecular docking approach,this study systematically investigated the synergistic mechanism of the herb pair DC and LR in RA treatment.Active components and their corresponding targets were retrieved from the TCMSP database and relevant literature,and RA-related targets were collected from established disease databases.A total of 73 overlapping targets between DC-LR and RA were identified,among which core targets such as AKT1,TNF,and CASP3 were highlighted.GO and KEGG enrichment analyses revealed that these targets are involved in biological processes such as oxidative stress response and cell migration,and are significantly enriched in key pathways including HIF-1,TNF,and PI3K-Akt signaling pathways.Compatibility analysis further revealed that the combination of DC and LR may enhance therapeutic effects through synergistic regulation of shared targets and complementary modulation of upstream and downstream pathway components.Molecular docking confirmed strong binding affinities between core active components and key targets.This study provides a multi-dimensional“component-target-pathway”perspective on the potential synergistic anti-RA mechanism of the DC-LR herb pair,offering a theoretical basis for further experimental validation and clinical application.展开更多
End-to-end Temporal Action Detection(TAD)has achieved remarkable progress in recent years,driven by innovations in model architectures and the emergence of Video Foundation Models(VFMs).However,existing TAD methods th...End-to-end Temporal Action Detection(TAD)has achieved remarkable progress in recent years,driven by innovations in model architectures and the emergence of Video Foundation Models(VFMs).However,existing TAD methods that perform full fine-tuning of pretrained video models often incur substantial computational costs,which become particularly pronounced when processing long video sequences.Moreover,the need for precise temporal boundary annotations makes data labeling extremely expensive.In low-resource settings where annotated samples are scarce,direct fine-tuning tends to cause overfitting.To address these challenges,we introduce Dynamic LowRank Adapter(DyLoRA),a lightweight fine-tuning framework tailored specifically for the TAD task.Built upon the Low-Rank Adaptation(LoRA)architecture,DyLoRA adapts only the key layers of the pretrained model via low-rank decomposition,reducing the number of trainable parameters to less than 5%of full fine-tuning methods.This significantly lowers memory consumption and mitigates overfitting in low-resource settings.Notably,DyLoRA enhances the temporal modeling capability of pretrained models by optimizing temporal dimension weights,thereby alleviating the representation misalignment of temporal features.Experimental results demonstrate that DyLoRA-TAD achieves impressive performance,with 73.9%mAP on THUMOS14,39.52%on ActivityNet-1.3,and 28.2%on Charades,substantially surpassing the best traditional feature-based methods.展开更多
Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized byclinical symptoms of diarrhea and mucopurulent bloody stools, and its incidenceis increasing globally. The etiology and pathogenesis of U...Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized byclinical symptoms of diarrhea and mucopurulent bloody stools, and its incidenceis increasing globally. The etiology and pathogenesis of UC remain elusive. Currenttherapeutic approaches, including anti-inflammatory, immunosuppressiveand immunomodulating agents, are often limited in efficacy and frequently associatedwith adverse drug reactions. Therefore, there is an urgent need to developsafer and more effective treatment strategies to address the limitations of existingtherapies. Scutellaria baicalensis Georgi (HQ), a traditional Chinese medicinal herb,has been employed in the treatment of UC for over 2000 years. Recent studieshave demonstrated that HQ contains multiple active components capable oftreating UC through anti-inflammation, immune modulation, intestinal barrierprotection, antioxidant activity, and regulation of the gut microbiota. This paperreviews recent studies on the mechanism of action and clinical trials of HQ intreating UC based on relevant literature, with the aim of providing valuable insightsinto future treatment approaches.展开更多
Deep neural networks have achieved excellent classification results on several computer vision benchmarks.This has led to the popularity of machine learning as a service,where trained algorithms are hosted on the clou...Deep neural networks have achieved excellent classification results on several computer vision benchmarks.This has led to the popularity of machine learning as a service,where trained algorithms are hosted on the cloud and inference can be obtained on real-world data.In most applications,it is important to compress the vision data due to the enormous bandwidth and memory requirements.Video codecs exploit spatial and temporal correlations to achieve high compression ratios,but they are computationally expensive.This work computes the motion fields between consecutive frames to facilitate the efficient classification of videos.However,contrary to the normal practice of reconstructing the full-resolution frames through motion compensation,this work proposes to infer the class label from the block-based computed motion fields directly.Motion fields are a richer and more complex representation of motion vectors,where each motion vector carries the magnitude and direction information.This approach has two advantages:the cost of motion compensation and video decoding is avoided,and the dimensions of the input signal are highly reduced.This results in a shallower network for classification.The neural network can be trained using motion vectors in two ways:complex representations and magnitude-direction pairs.The proposed work trains a convolutional neural network on the direction and magnitude tensors of the motion fields.Our experimental results show 20×faster convergence during training,reduced overfitting,and accelerated inference on a hand gesture recognition dataset compared to full-resolution and downsampled frames.We validate the proposed methodology on the HGds dataset,achieving a testing accuracy of 99.21%,on the HMDB51 dataset,achieving 82.54%accuracy,and on the UCF101 dataset,achieving 97.13%accuracy,outperforming state-of-the-art methods in computational efficiency.展开更多
Background:In 2021,the American College of Medical Genetics and Genomics(ACMG)recommended reporting actionable genotypes in 73 genes associated with diseases for which preventive or therapeutic measures are available....Background:In 2021,the American College of Medical Genetics and Genomics(ACMG)recommended reporting actionable genotypes in 73 genes associated with diseases for which preventive or therapeutic measures are available.Evaluations of the association of actionable genotypes in these genes with life span are currently lacking.展开更多
Offshore structures are constantly subjected to the complex forces of the marine environment,including wind,sea waves,currents,and seismic loadings.Among these,wind and sea wave forces persist throughout the structure...Offshore structures are constantly subjected to the complex forces of the marine environment,including wind,sea waves,currents,and seismic loadings.Among these,wind and sea wave forces persist throughout the structure’s lifetime.This study proposes a dynamic analysis approach that incorporates both time and frequency domain methods to investigate the structural responses of offshore structures under the combined effects of wind and wave forces.A wind wave-pier coupling dynamic model is first developed using a small-scale single pier,with corresponding dynamic equilibrium equations established.Fluctuating wind and sea waves are simulated using the weighted amplitude wave superposition(WAWS)method and linear superposition,respectively.Wind and wave load histories are then derived via Fourier transforms.The structural dynamic responses under different loading scenarios(wind only,wave only,and combined wind and wave)are analyzed using the Newmarkβmethod.Additionally,the effects of varying wind and wave parameters on structural responses are evaluated.The simulation results demonstrate that the structural responses to wind-wave coupling are smaller than the superimposed effects of wind and wave forces acting independently.When wind speeds are relatively low,wave forces dominate structural displacement and serve as the primary source of vibration.展开更多
Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical eff...Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical effects and mechanisms in immune enhancement,adjunctive anti-tumor activity,and regulation of glucose/lipid metabolism.Three clinical trials were conducted.In an immune study,120 healthy volunteers(CD4+T cell count 500–1000 cells/μL)received 150 mg/day GFP-D for 8 weeks,resulting in significant increases in CD4+T cells(from 632±95 to 812±108 cells/μL,28.5%increase,within the physiological activation range),CD4+/CD8+ratio,NK cell activity,IL-2,and IFN-γ(all P<0.001 vs.placebo).An anti-tumor study with 80 advanced cancer patients(stratified by age,tumor stage,and histotype)showed that adding 1000 mg/day GFP-D to chemotherapy improved objective response rate(52.5%vs.30.0%,P=0.036,95%CI:1.02–3.87),one-year progression-free survival(55.8%vs.33.3%,P=0.022),and preserved immune parameters versus chemotherapy alone.A metabolic study in 90 type 2 diabetes patients found that 400 mg/day GFP-D for 12 weeks significantly lowered fasting glucose,HbA1c,total cholesterol,triglycerides,and LDL-C,while raising HDL-C(from 1.0±0.2 to 1.2±0.2 mmol/L,20%increase,supported by increased AMPK phosphorylation).Mechanistically,immune enhancement involves macrophage/dendritic cell activation via Dectin-1/TLR4 receptors(confirmed by increased receptor expression and downstream signaling molecules),promoting cytokine-driven T/NK cell responses.Anti-tumor effects stem from immunomodulation,direct induction of cancer cell apoptosis(via mitochondrial/caspase pathways,verified by increased Bax/Bcl-2 ratio and caspase-3 activation),and angiogenesis inhibition by downregulating VEGF.Metabolic benefits are linked to AMPK pathway activation in liver/muscle(confirmed by increased p-AMPK/AMPK ratio),enhancing glucose uptake and inhibiting gluconeogenesis/lipogenesis,alongside modulation of gut microbiota(increased Bifidobacterium and Lactobacillus abundance).All trials reported no severe adverse events related to GFP-D;liver/kidney function parameters(ALT,AST,creatinine,urea nitrogen)remained within normal ranges throughout the intervention.Collectively,GFP-D emerges as a multi-functional bioactive agent with substantial therapeutic potential.展开更多
Branded Matchmaking Services Integrated with Rural Revitalization Hunan Women's Federation and Hunan Provincial Department of Agriculture and Rural Affairs conducted a rural-matchmaking-demonstration activity rece...Branded Matchmaking Services Integrated with Rural Revitalization Hunan Women's Federation and Hunan Provincial Department of Agriculture and Rural Affairs conducted a rural-matchmaking-demonstration activity recently in Shibadong,a village in Xiangxi,a region in Central China's Hunan Province.More than 120 young,single people attended.展开更多
-A composite pipeline is defined as a pipeline system composed of one big pipe and one or several small pipes. Based on the theory of wave- current interaction and physical model test, the hydrodynamic characteristics...-A composite pipeline is defined as a pipeline system composed of one big pipe and one or several small pipes. Based on the theory of wave- current interaction and physical model test, the hydrodynamic characteristics of the submarine composite pipeline in wave-current coexisting field (both regular and irregular waves) are investigated. The so-called 'modified diameter method' is used for analyzing the in-fine hydrodynamic coefficients of the composite pipeline, which are well related to KC number. The comparison of test data for regular and irregular waves shows that in the region of 90 > KC> 20, the results in these two cases can be unified. The effect of water depth is analyzed in details. The relationships between CD, CM and KC , which are based on the results of present research, may be used as a reference in engineering design.展开更多
基金This researchis supported by Research Fund for Doctoral Programs of Higher Education (Grant No.20030141006) ,and a Program for Changjiang Scholars and Innovative Research Teams in Universities (Grant No.IRT0420)
文摘A higher order boundary dement method (HOBEM) is implemented for wave-current action on structures. The freeterm coefficient and Cauchy principal value ( GPV) integrals are computed by direct methods. Numerical experiments are carried out to validate the computation of free-term coefficient and GPV integrals. The results show that the computation precision of free-term coefficient is very high for various bodies, even with edges and corners, and the convergence speed is fast for CPV integrals for different meshes. The comparison of the second order mean drift force due to wave-current action on a uniform cylinder is made with an analytic solution. It is found that good agreement exists between the present calculation and the analytic solutions. Finally, the numerical code is applied for computing wave-current action on Snorrc TLP.
基金Supported by the Development and Application Project of Ship CAE Software.
文摘Studies of wave-current interactions are vital for the safe design of structures.Regular waves in the presence of uniform,linear shear,and quadratic shear currents are explored by the High-Level Green-Naghdi model in this paper.The five-point central difference method is used for spatial discretization,and the fourth-order Adams predictor-corrector scheme is employed for marching in time.The domain-decomposition method is applied for the wave-current generation and absorption.The effects of currents on the wave profile and velocity field are examined under two conditions:the same velocity of currents at the still-water level and the constant flow volume of currents.Wave profiles and velocity fields demonstrate substantial differences in three types of currents owing to the diverse vertical distribution of current velocity and vorticity.Then,loads on small-scale vertical cylinders subjected to regular waves and three types of background currents with the same flow volume are investigated.The maximum load intensity and load fluctuation amplitude in uniform,linear shear,and quadratic shear currents increase sequentially.The stretched superposition method overestimates the maximum load intensity and load fluctuation amplitude in opposing currents and underestimates these values in following currents.The stretched superposition method obtains a poor approximation for strong nonlinear waves,particularly in the case of the opposing quadratic shear current.
基金financially supported by the National Key Research and Development Program of China (Grant No. 2021YFB2601100)the National Natural Science Foundation of China (Grant No. 51979190)。
文摘Under the combination of currents and waves, seabed scour occurs around offshore wind turbine foundations, which affects the stability and safe operation of offshore wind turbines. In this study, physical model experiments under unidirectional flow, bidirectional flow, and wave-current interactions with different flow directions around the pile group foundation were first conducted to investigate the development of scour around the pile group foundation.Additionally, a three-dimensional scour numerical model was established via the open-source software REEF3D to simulate the flow field and scour around the prototype-scale foundation. The impact of flow on scour was discussed.Under unidirectional flow, scour equilibrium was reached more quickly, with the maximum scour depth reaching approximately 1.2 times the pile diameter and the extent of the scour hole spanning about 4.9 times the pile diameter.Compared with those under unidirectional flow, the scour depths under combinations of currents and waves, as well as bidirectional flow, were slightly smaller. However, the morphology of scour holes was more uniform and symmetrical. The numerical simulation results show good agreement with the experimental data, demonstrating the impact of varying flow directions on the velocity distribution around the foundation, the morphology of scour holes, and the location of the maximum scour depth.
基金financially supported by the National Natural Science Foundation of China(Grant No.51309158)funds from the National Key Scientific Instrument and Equipment Development Project(Grant No.2013YQ04091108)Important and Large Scientific and Technical Project of the Ministry of Communications(Grant No.201132874640)
文摘The movement of sediment in estuary and on coast is directly restricted by the bed shear stress. Therefore, the research on the basic problem of sediment movement by the bed shear stress is an important way to research the theory of sediment movement. However, there is not a measuring and computing method to measure the bed shear stress under a complicated dynamic effect like wave and current. This paper describes the measurement and test research on the bed shear stress in a long launder of direct current by the new instrument named thermal shearometer based on micro-nanotechnology. As shown by the research results, the thermal shearometer has a high response frequency and strong stability. The measured results can reflect the basic change of the bed shear stress under wave and wave-current effect, and confirm that the method of measuring bed shear stress under wave-current effect with thermal shearometer is feasible. Meanwhile, a preliminary method to compute the shear stress compounded by wave-current is put forward according to the tested and measured results, and then a reference for further study on the basic theory of sediment movement under a complicated dynamic effect is provided.
基金This paper was supported bythe Foundationforthe Author of National Excellent Doctoral Dissertation of P.R.China(Grant No.200428) the National Natural Science Foundation of China (Grant Nos .10272072 and 50424913) +1 种基金theShanghai Natural Science Foundation (Grant No.05ZR14048) the Shanghai Leading Academic Discipline Pro-ject (Grant No. Y0103)
文摘The interaction between waves, currents and bottoms in estuarine and coastal regions is ubiquitious, in particular the dynamic mechanism of waves on large-scale slowly varying currents. The wave action concept may be extended and applicated to the study of the mechanism. Considering the effects of moving bottoms and starting from the Navier-Stokes equation of motion of a vinous fluid including the Coriolis force, a generalized mean-flow medel theory for the nearshore region, that is, a set of mean-flow equations and their generalized wave action equation involving the three new kinds of actions termed respectively as the current wave action, the bottom wave action and the dissipative wave action which can be applied to arbitrary depth over moving bottoms and ambient currents with a typical vertical structure, is developed by vertical integration and time-averaglng over a wave peried, thus extending the classical concept, wave action, from the ideal averaged flow conservative system to the real averaged flow dissipative dynamical system, and having a large range of application.
基金The Program for Scientific Research Start-up Funds of Guangdong Ocean University under contract No.101302/R18001the Fund of Southern Marine Science and Engineering Guangdong Laboratory(Zhanjiang)under contract No.ZJW-2019-08+1 种基金the National Key Research and Development Program of China under contract No.2016YFC1401403the National Natural Science Foundation of China under contract Nos 41476009 and 41776034
文摘Wave-current interaction and its effects on the hydrodynamic environment in the Beibu Gulf(BG) have been investigated via employing the Coupled Ocean–Atmosphere–Wave–Sediment Transport(COAWST) modeling system. The model could simulate reasonable hydrodynamics in the BG when validated by various observations.Vigorous tidal currents refract the waves efficiently and make the seas off the west coast of Hainan Island be the hot spot where currents modulate the significant wave height dramatically. During summer, wave-enhanced bottom stress could weaken the near-shore component of the gulf-scale cyclonic-circulation in the BG remarkably, inducing two major corresponding adjustments: Model results reveal that the deep-layer cold water from the southern BG makes critical contribution to maintaining the cold-water mass in the northern BG Basin.However, the weakened background circulation leads to less cold water transported from the southern gulf to the northern gulf, which finally triggers a 0.2℃ warming in the cold-water mass area;In the top areas of the BG, the suppressed background circulation reduces the transport of the diluted water to the central gulf. Therefore, more freshwater could be trapped locally, which then triggers lower sea surface salinity(SSS) in the near-field and higher SSS in the far-field.
基金Supported by the National Key Research and Development Program of China(No.2016YFC1402000)the National Natural Science Foundation of China(Nos.41376027,U1133001,41606024)+3 种基金the National Program on Global Change and Air-Sea Interaction(No.GASI-IPOVAI-01-06)the NSFC-Shandong Joint Fund for Marine Science Research Centers(No.U1406401)the NSFC Innovative Group Grant Project(No.41421005)the High Performance Computing Environment Qingdao Branch of Chinese Academy of Science(CAS)
文摘The northern South China Sea(SCS) is frequently affected by typhoons. During severe storm events, wave-current interactions produce storm surges causing enormous damage in the path of the typhoon. To evaluate the influence of wave-current interactions on storm surge, we used a coupled ocean-atmospherewave-sediment transport(COAWST) modeling system with radiation-stress and vortex-force formulations to simulate two typically intense tropical storms that invaded the SCS, namely Typhoons Nuri(2008) and Hagupit(2008), and compared results with observations from the Hong Kong Observatory. Both radiationstress and vortex-force formulations significantly improved the accuracy of the simulation. Depending on which typhoon and the topography encountered, the influence of surface waves on the oceanic circulation showed different characteristics, including the differences of range and intensity of storm surge between vortex-force and radiation-stress experiments. During typhoon landing, strong sea-surface elevation in concert with wave set-up/set-down caused the adjustment of the momentum balance. In the direction perpendicular to the current, but especially in the cross-shore direction, the pressure gradient and wave effects on the current dominated the momentum balance.
基金Supported by the National Natural Science Foundation of China(Nos.U1706216,41976010,42006027,U1806227)the Natural Science Foundation of Shandong Province,China(No.ZR2016DQ16)+2 种基金the Key Deployment Project of Center for Ocean Mega-Science,Chinese Academy of Sciences(Nos.COMS2019J02,COMS2019J05)the Chinese Academy of Sciences Strategic Priority Project(Nos.XDA19060202,XDA19060502)the National Key Research and Development Program of China(No.2016YFC1402000)。
文摘We examined the influences of the wind fi eld and wave-current interaction(WCI)on the numerical simulation results of typhoon-induced wind waves in the northern East China Sea(NECS)using the coupled Simulating Waves Nearshore+Advanced Circulation(SWAN+ADCIRC)model.The simulations were performed during two typhoon events(Lekima and Muifa),and two widely used reanalysis wind fields,the Climate Forecast System Version 2(CFSv2)from the National Centers for Environmental Prediction(NCEP)and the fifth-generation European Centre for Medium-Range Weather Forecasts(ECMWF)Reanalysis(ERA5),were compared.The results indicate that the ERA5 and CFSv2 wind fields both reliably reproduced the wind variations measured by in-situ buoys,and the accuracy of the winds from ERA5 were generally better than those from CFSv2 because CFSv2 tended to overestimate the wind speed and the simulated significant wave height(SWH),particularly the peak SWH.The WCI effects between the two wind field simulations were similar;these effects enhanced the SWH throughout the nearshore NECS during both typhoons but suppressed the SWH on the right side of the Typhoon Muifa track in the deep and off shore sea areas.In summary,variations in the water depth and current propagation direction dominate the modulation of wave height.
基金financially supported by the National Natural Science Foundation of China(Grant No.51861130358,51609109)the State Key Laboratory of Ocean Engineering,China(Shanghai Jiao Tong University)(Grant No.1905)+1 种基金the Newton Advanced Fellowships of the Royal Societythe Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX20_3153)。
文摘The nonlinear dynamic response induced by the wave-current interaction on a deepwater steep wave riser(SWR)is numerically investigated based on a three-dimensional(3 D)time-domain finite element method(FEM).The governing equation considering internal flow is established in the global coordinate system.The whole SWR consists of three segments:the decline segment,buoyancy segment and hang-off segment,in which the buoyancy segment is wrapped by several buoyancy modules in the middle section,leading to the arch bend and sag bend.A Newmark-β iterative scheme is adopted for the accurate analysis to solve the governing equation and update the dynamic response at each time step.The proposed method is verified through the published results for the dynamic response of steel catenary riser(SCR)and static configuration of steel lazy wave riser(SLWR).Simulations are executed to study the influence of wave height,current velocity/direction,internal flow density/velocity and top-end pressure on the tension,configuration and bending moment of the SWR.The results indicate that the influence of the current on the configuration and mechanical behavior of the SWR is greater than that of the wave,especially in the middle section.With increasing current velocity,the suspending height of the middle section drops,meanwhile,its bending moment decreases accordingly,but the tension increases significantly.For a fixed external load,the increasing internal flow density induces the amplification of the tension at the hang-off segment and the mitigation at the decline segment,while the opposite trend occurs at the bending moment.
文摘The aim of this paper is to present an analytical expression for the streamwise velocity distribution in a non-uniform flow in the presence of waves; the correlation between the horizontal and vertical velocity components has been compreheusively examined. Different from previous researches which attributed the deviation of velocity from the classical log-law to the wave Reynolds stress, i.e. - ρ uv^- only, this study demonstrates that the momentum flux caused by mean velocities, i.e., u^- and v^-, is also responsible for the velocity deviation, and it is found that the streamwise velocity for a flow in the presence of non-zero wall-normal velocity does not follow the classical log-law, but the modified log-law proposed in this study based on simplified mixing-length theorem. The validity of the modified log-law has been verified by use of available experimental data from published sources for combined wave-current flows, and good agreement between the predicted and observed velocity profiles has been achieved.
基金supported by National Training Program of Innovation and Entrepreneurship for Undergraduates(202510163044).
文摘The combination of Daphnes Cortex(DC)and Liquorice Root(LR),two traditional Chinese medicinal herbs,has shown significant therapeutic effects on rheumatoid arthritis(RA),but its synergistic mechanism of action remains to be elucidated.Employing a network pharmacology and molecular docking approach,this study systematically investigated the synergistic mechanism of the herb pair DC and LR in RA treatment.Active components and their corresponding targets were retrieved from the TCMSP database and relevant literature,and RA-related targets were collected from established disease databases.A total of 73 overlapping targets between DC-LR and RA were identified,among which core targets such as AKT1,TNF,and CASP3 were highlighted.GO and KEGG enrichment analyses revealed that these targets are involved in biological processes such as oxidative stress response and cell migration,and are significantly enriched in key pathways including HIF-1,TNF,and PI3K-Akt signaling pathways.Compatibility analysis further revealed that the combination of DC and LR may enhance therapeutic effects through synergistic regulation of shared targets and complementary modulation of upstream and downstream pathway components.Molecular docking confirmed strong binding affinities between core active components and key targets.This study provides a multi-dimensional“component-target-pathway”perspective on the potential synergistic anti-RA mechanism of the DC-LR herb pair,offering a theoretical basis for further experimental validation and clinical application.
基金supported by the National Natural Science Foundation of China(Grant No.62266054)the Major Science and Technology Project of Yunnan Province(Grant No.202402AD080002)the Scientific Research Fund of the Yunnan Provincial Department of Education(Grant No.2025Y0302).
文摘End-to-end Temporal Action Detection(TAD)has achieved remarkable progress in recent years,driven by innovations in model architectures and the emergence of Video Foundation Models(VFMs).However,existing TAD methods that perform full fine-tuning of pretrained video models often incur substantial computational costs,which become particularly pronounced when processing long video sequences.Moreover,the need for precise temporal boundary annotations makes data labeling extremely expensive.In low-resource settings where annotated samples are scarce,direct fine-tuning tends to cause overfitting.To address these challenges,we introduce Dynamic LowRank Adapter(DyLoRA),a lightweight fine-tuning framework tailored specifically for the TAD task.Built upon the Low-Rank Adaptation(LoRA)architecture,DyLoRA adapts only the key layers of the pretrained model via low-rank decomposition,reducing the number of trainable parameters to less than 5%of full fine-tuning methods.This significantly lowers memory consumption and mitigates overfitting in low-resource settings.Notably,DyLoRA enhances the temporal modeling capability of pretrained models by optimizing temporal dimension weights,thereby alleviating the representation misalignment of temporal features.Experimental results demonstrate that DyLoRA-TAD achieves impressive performance,with 73.9%mAP on THUMOS14,39.52%on ActivityNet-1.3,and 28.2%on Charades,substantially surpassing the best traditional feature-based methods.
基金Supported by National Natural Science Foundation of China,No.82374200Construction of Traditional Chinese Medicine Inheritance and Innovation Development Demonstration Pilot Projects in Pudong New Area-High-Level Research-Oriented Traditional Chinese Medicine Hospital Construction,No.YC-2023-0901.
文摘Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized byclinical symptoms of diarrhea and mucopurulent bloody stools, and its incidenceis increasing globally. The etiology and pathogenesis of UC remain elusive. Currenttherapeutic approaches, including anti-inflammatory, immunosuppressiveand immunomodulating agents, are often limited in efficacy and frequently associatedwith adverse drug reactions. Therefore, there is an urgent need to developsafer and more effective treatment strategies to address the limitations of existingtherapies. Scutellaria baicalensis Georgi (HQ), a traditional Chinese medicinal herb,has been employed in the treatment of UC for over 2000 years. Recent studieshave demonstrated that HQ contains multiple active components capable oftreating UC through anti-inflammation, immune modulation, intestinal barrierprotection, antioxidant activity, and regulation of the gut microbiota. This paperreviews recent studies on the mechanism of action and clinical trials of HQ intreating UC based on relevant literature, with the aim of providing valuable insightsinto future treatment approaches.
基金Supported by Princess Nourah bint Abdulrahman University Researchers Supporting Project number(PNURSP2025R896).
文摘Deep neural networks have achieved excellent classification results on several computer vision benchmarks.This has led to the popularity of machine learning as a service,where trained algorithms are hosted on the cloud and inference can be obtained on real-world data.In most applications,it is important to compress the vision data due to the enormous bandwidth and memory requirements.Video codecs exploit spatial and temporal correlations to achieve high compression ratios,but they are computationally expensive.This work computes the motion fields between consecutive frames to facilitate the efficient classification of videos.However,contrary to the normal practice of reconstructing the full-resolution frames through motion compensation,this work proposes to infer the class label from the block-based computed motion fields directly.Motion fields are a richer and more complex representation of motion vectors,where each motion vector carries the magnitude and direction information.This approach has two advantages:the cost of motion compensation and video decoding is avoided,and the dimensions of the input signal are highly reduced.This results in a shallower network for classification.The neural network can be trained using motion vectors in two ways:complex representations and magnitude-direction pairs.The proposed work trains a convolutional neural network on the direction and magnitude tensors of the motion fields.Our experimental results show 20×faster convergence during training,reduced overfitting,and accelerated inference on a hand gesture recognition dataset compared to full-resolution and downsampled frames.We validate the proposed methodology on the HGds dataset,achieving a testing accuracy of 99.21%,on the HMDB51 dataset,achieving 82.54%accuracy,and on the UCF101 dataset,achieving 97.13%accuracy,outperforming state-of-the-art methods in computational efficiency.
文摘Background:In 2021,the American College of Medical Genetics and Genomics(ACMG)recommended reporting actionable genotypes in 73 genes associated with diseases for which preventive or therapeutic measures are available.Evaluations of the association of actionable genotypes in these genes with life span are currently lacking.
基金Project(2022YFB2302700)supported by the National Key Research and Development Program of China。
文摘Offshore structures are constantly subjected to the complex forces of the marine environment,including wind,sea waves,currents,and seismic loadings.Among these,wind and sea wave forces persist throughout the structure’s lifetime.This study proposes a dynamic analysis approach that incorporates both time and frequency domain methods to investigate the structural responses of offshore structures under the combined effects of wind and wave forces.A wind wave-pier coupling dynamic model is first developed using a small-scale single pier,with corresponding dynamic equilibrium equations established.Fluctuating wind and sea waves are simulated using the weighted amplitude wave superposition(WAWS)method and linear superposition,respectively.Wind and wave load histories are then derived via Fourier transforms.The structural dynamic responses under different loading scenarios(wind only,wave only,and combined wind and wave)are analyzed using the Newmarkβmethod.Additionally,the effects of varying wind and wave parameters on structural responses are evaluated.The simulation results demonstrate that the structural responses to wind-wave coupling are smaller than the superimposed effects of wind and wave forces acting independently.When wind speeds are relatively low,wave forces dominate structural displacement and serve as the primary source of vibration.
文摘Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical effects and mechanisms in immune enhancement,adjunctive anti-tumor activity,and regulation of glucose/lipid metabolism.Three clinical trials were conducted.In an immune study,120 healthy volunteers(CD4+T cell count 500–1000 cells/μL)received 150 mg/day GFP-D for 8 weeks,resulting in significant increases in CD4+T cells(from 632±95 to 812±108 cells/μL,28.5%increase,within the physiological activation range),CD4+/CD8+ratio,NK cell activity,IL-2,and IFN-γ(all P<0.001 vs.placebo).An anti-tumor study with 80 advanced cancer patients(stratified by age,tumor stage,and histotype)showed that adding 1000 mg/day GFP-D to chemotherapy improved objective response rate(52.5%vs.30.0%,P=0.036,95%CI:1.02–3.87),one-year progression-free survival(55.8%vs.33.3%,P=0.022),and preserved immune parameters versus chemotherapy alone.A metabolic study in 90 type 2 diabetes patients found that 400 mg/day GFP-D for 12 weeks significantly lowered fasting glucose,HbA1c,total cholesterol,triglycerides,and LDL-C,while raising HDL-C(from 1.0±0.2 to 1.2±0.2 mmol/L,20%increase,supported by increased AMPK phosphorylation).Mechanistically,immune enhancement involves macrophage/dendritic cell activation via Dectin-1/TLR4 receptors(confirmed by increased receptor expression and downstream signaling molecules),promoting cytokine-driven T/NK cell responses.Anti-tumor effects stem from immunomodulation,direct induction of cancer cell apoptosis(via mitochondrial/caspase pathways,verified by increased Bax/Bcl-2 ratio and caspase-3 activation),and angiogenesis inhibition by downregulating VEGF.Metabolic benefits are linked to AMPK pathway activation in liver/muscle(confirmed by increased p-AMPK/AMPK ratio),enhancing glucose uptake and inhibiting gluconeogenesis/lipogenesis,alongside modulation of gut microbiota(increased Bifidobacterium and Lactobacillus abundance).All trials reported no severe adverse events related to GFP-D;liver/kidney function parameters(ALT,AST,creatinine,urea nitrogen)remained within normal ranges throughout the intervention.Collectively,GFP-D emerges as a multi-functional bioactive agent with substantial therapeutic potential.
文摘Branded Matchmaking Services Integrated with Rural Revitalization Hunan Women's Federation and Hunan Provincial Department of Agriculture and Rural Affairs conducted a rural-matchmaking-demonstration activity recently in Shibadong,a village in Xiangxi,a region in Central China's Hunan Province.More than 120 young,single people attended.
文摘-A composite pipeline is defined as a pipeline system composed of one big pipe and one or several small pipes. Based on the theory of wave- current interaction and physical model test, the hydrodynamic characteristics of the submarine composite pipeline in wave-current coexisting field (both regular and irregular waves) are investigated. The so-called 'modified diameter method' is used for analyzing the in-fine hydrodynamic coefficients of the composite pipeline, which are well related to KC number. The comparison of test data for regular and irregular waves shows that in the region of 90 > KC> 20, the results in these two cases can be unified. The effect of water depth is analyzed in details. The relationships between CD, CM and KC , which are based on the results of present research, may be used as a reference in engineering design.