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A Transient Thermohydrodynamics Study of Plain Journal Bearings Using Newton-Raphson Method Analysis 认领 引用 被引量:1
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作者 富彦丽 马希直 朱均 《Chinese Journal of Aeronautics》 EI CAS 2003年第4期233-240,共8页
The present paper proposes three-dimensional model necessary to calculate the transient temperature field in a journal bearing submitted to a sudden change in speed and load and analyzes the bearing performance numeri... The present paper proposes three-dimensional model necessary to calculate the transient temperature field in a journal bearing submitted to a sudden change in speed and load and analyzes the bearing performance numerically. Thermal deformation of the bush and realistic thermal boundary conditions at oil and bush interface are considered. At each time step a Newton-Raphson method is used to solve the Reynolds equation, film thickness equation and the motion equation of the journal simultaneously to obtain the pressure distribution and the velocity of the journal center. Then the fluid film force is acquired through integral of fluid film force and the acceleration and position of the journal center are acquired through differences of the velocity. The energy equations of the oil film and the bush are solved simultaneously by using an efficient finite difference scheme. Then the transient three dimensional temperature field of the bearing is acquired by combining the energy equations and the Reynolds equation through the nodal temperature and pressure. It is found that the approaches introduced here converge quickly and save calculation time greatly. 展开更多
关键词 thermohydrodynamics transient Newton-Raphson method journal bearing
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Principle of MSD floating-point division based on Newton-Raphson method on ternary optical computer 认领 引用
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作者 沈云付 胡鹏飞 樊孝领 《Journal of Shanghai University(English Edition)》 2011年第5期347-351,共5页
The division operation is not frequent relatively in traditional applications, but it is increasingly indispensable and important in many modern applications. In this paper, the implementation of modified signed-digit... The division operation is not frequent relatively in traditional applications, but it is increasingly indispensable and important in many modern applications. In this paper, the implementation of modified signed-digit (MSD) floating-point division using Newton-Raphson method on the system of ternary optical computer (TOC) is studied. Since the addition of MSD floating-point is carry-free and the digit width of the system of TOC is large, it is easy to deal with the enough wide data and transform the division operation into multiplication and addition operations. And using data scan and truncation the problem of digits expansion is effectively solved in the range of error limit. The division gets the good results and the efficiency is high. The instance of MSD floating-point division shows that the method is feasible. 展开更多
关键词 ternary optical computer (TOC) modified signed-digit (MSD) division Newton-Raphson method scan data truncation
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Forward kinematics analysis of parallel manipulator using modified global Newton-Raphson method 认领 引用 被引量:26
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作者 杨炽夫 郑淑涛 +2 位作者 靳军 朱思斌 韩俊伟 《Journal of Central South University》 SCIE EI CAS 2010年第6期1264-1270,共7页
In order to obtain direct solutions of parallel manipulator without divergence in real time,a modified global Newton-Raphson(MGNR) algorithm was proposed for forward kinematics analysis of six-degree-of-freedom(DOF) p... In order to obtain direct solutions of parallel manipulator without divergence in real time,a modified global Newton-Raphson(MGNR) algorithm was proposed for forward kinematics analysis of six-degree-of-freedom(DOF) parallel manipulator.Based on geometrical frame of parallel manipulator,the highly nonlinear equations of kinematics were derived using analytical approach.The MGNR algorithm was developed for the nonlinear equations based on Tailor expansion and Newton-Raphson iteration.The procedure of MGNR algorithm was programmed in Matlab/Simulink and compiled to a real-time computer with Microsoft visual studio.NET for implementation.The performance of the MGNR algorithms for 6-DOF parallel manipulator was analyzed and confirmed.Applying the MGNR algorithm,the real generalized pose of moving platform is solved by using the set of given positions of actuators.The theoretical analysis and numerical results indicate that the presented method can achieve the numerical convergent solution in less than 1 ms with high accuracy(1×10-9 m in linear motion and 1×10-9 rad in angular motion),even the initial guess value is far from the root. 展开更多
关键词 parallel manipulator forward kinematics global Newton-Raphson real-time system
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MULTI-PARAMETER ACCELERATED MODIFIED NEWTON-RAPHSON METHODS FOR RIGIDPLASTIC FE ANALYSIS 认领 引用
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作者 Shi Gang Liu Xiaolin 《Acta Mechanica Solida Sinica》 SCIE 2002年第4期323-331,共9页
Applications of certain multi-parameter acceleration techniques used with themodified New-ton-Raphson (mN-R) methods to solve the nonlinear equations arising from rigid-plasticfinite element analysis are investigated.... Applications of certain multi-parameter acceleration techniques used with themodified New-ton-Raphson (mN-R) methods to solve the nonlinear equations arising from rigid-plasticfinite element analysis are investigated. New modified multi-parameter techniques, developed fromCrisfield's multi-parameter methods, are utilized to solve these nonlinear equations. The numericalperformance of these techniques is compared with the standard Newton-Raphson method (sN-R),Crisfield's single parameter method (C1), Crisfield's two parameter method (C2) and Crisfield'sthree parameter method (C3). The new techniques do not involve additional residual force calculationand require little extra computational effort. In addition, they are more robust and efficient thanother existing acceleration techniques. 展开更多
关键词 rigid-plastic FEM standard newton-raphson method modified newton-raphsonmethod crisfield's multi-parameter accelerated techniques modified multi-parameter acceleratedtechniques
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Simulation of Steel Reinforcement on the Nonlinear Behaviour of Slender Glulam Beam Columns by Using the Newton-Raphson Method 认领 引用
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作者 Martial Ourmama Marcelline Blanche Manjia Edmond Dawak Fezeu 《Open Journal of Applied Sciences》 2024年第2期243-266,共24页
The current theory in NF EN 1995-1-1/NA of Eurocode 5, which is based on maximum deflection, has been investigated on softwoods. Therefore, this theory is not adapted for slender glulam beam columns made of tropical h... The current theory in NF EN 1995-1-1/NA of Eurocode 5, which is based on maximum deflection, has been investigated on softwoods. Therefore, this theory is not adapted for slender glulam beam columns made of tropical hardwood species from the Congo Basin. This maximum deflection is caused by a set of loads applied to the structure. However, Eurocode 5 doesn’t provide how to predict this deflection in case of long-term load for such structures. This can be done by studying load-displacement (P-Δ) behaviour of these structures while taking into account second order effects. To reach this goal, a nonlinear analysis has been performed on a three-dimensional beam column embedded on both ends. Since conducting experimental investigations on large span structural products is time-consuming and expensive especially in developing countries, a numerical model has been implemented using the Newton-Raphson method to predict load-displacement (P-Δ) curve on a slender glulam beam column made of tropical hardwood species. On one hand, the beam has been analyzed without wood connection. On the other hand, the beam has been analyzed with a bolted wood connection and a slotted-in steel plate. The load cases considered include self-weight and a uniformly applied long-term load. Combinations of serviceability limit states (SLS) and ultimate limit states (ULS) have also been considered, among other factors. A finite-element software RFEM 5 has been used to implement the model. The results showed that the use of steel can reduce displacement by 20.96%. Additionally, compared to the maximum deflection provided by Eurocode 5 for softwoods, hardwoods can exhibit an increasing rate of 85.63%. By harnessing the plastic resistance of steel, the bending resistance of wood can be increased by 32.94%. 展开更多
关键词 Nonlinear Analysis Newton-Raphson Method Maximum Deflection Bolted Wood Connection Hardwood Species
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Chaos in Solving Polynomial Systems for Computational Kinematics by Newton-Raphson Method 认领 引用
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作者 谢进 陈永 《Journal of Modern Transportation》 2000年第2期123-128,共6页
Problems in mechanism analysis and synthesis and robotics lead naturally to systems of nonlinear equations. In this paper, an approach based on Newton Raphson method and the property of fractals is presented to obtain... Problems in mechanism analysis and synthesis and robotics lead naturally to systems of nonlinear equations. In this paper, an approach based on Newton Raphson method and the property of fractals is presented to obtaining all roots of equation. An example from plane mechanism synthesis is given to demonstrate the idea of the method. 展开更多
关键词 chaos computational kinematics Newton-Raphson metho?
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Broadband ground motion simulation and analysis of a near-fault 3D basin-mountain coupling site based on the hybrid method 认领 引用 被引量:1
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作者 Liu Zhongxian Tang Kang +2 位作者 Li Chengcheng Yuan Xiaoming Zhang Hai 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2026年第1期87-110,共24页
This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SE... This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SEM),which is used to simulate low-frequency ground motion(f1 Hz).A fourth-order Butterworth filter with zero phase shift is employed for time-domain filtering of low-and high-frequency time series at a crossover frequency of 1 Hz,merging the low and high-frequency ground motions into a broadband time series.Taking an Ms 6.8 Luding earthquake,as an example,this hybrid method was used for a rapid and efficient simulation analysis of broadband ground motion in the region.The accuracy and efficiency of this hybrid method were verified through comparisons with actually observed station data and empirical attenuation curves.Deterministic method simulation results revealed the effects of mountainous topography,basin effects,nonlinear effects within the basin’s sedimentary layers,and a coupling interaction between the basin and the mountains.The findings are consistent with similar studies,showing that near-fault sedimentary basins significantly focus and amplify strong ground motion,and the soil’s nonlinear behavior in the basin influences ground motion to varying extents at different distances from the fault.The mountainous topography impacts the basin’s response to ground motion,leading to barrier effects.This research provides a scientific foundation for seismic zoning,urban planning,and seismic design in nearfault mountain basin regions. 展开更多
关键词 hybrid ground motion simulation method spectral element method three-dimensional stochastic finite fault method near-fault basin-mountain coupling effect basin effect nonlinear effect
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Methods of preparation,structural characteristics of resistant starch and its relation to human health:a review 认领 引用 被引量:1
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作者 Weiyi Zhang Yang Yang +6 位作者 Chunmin Ma Bing Wang Xiaofei Liu Yan Wang Xin Bian Guang Zhang Na Zhang 《Food Science and Human Wellness》 SCIE CAS CSCD 2026年第4期1503-1519,共17页
Resistant starch(RS)comprises starch fractions that resist digestion in the small intestine and reach the colon,where they are fermented by the microbiota.Resistant starch harbors functional properties and healthpromo... Resistant starch(RS)comprises starch fractions that resist digestion in the small intestine and reach the colon,where they are fermented by the microbiota.Resistant starch harbors functional properties and healthpromoting ingredients that can regulate blood glucose and lipid levels,prevent cancer,and enhance the quality of life.Consequently,new technologies for the preparation of RS are continually being developed to support its industrial production.This review describes the structural and nutritional properties of RS and examines recent advancements in RS preparation methods.Emphasis is placed on how RS structure influences its properties and the physiological mechanisms in vivo.This review aims to stimulate further research into the preparation methods,functional characteristics,and utilization of RS,thereby supporting ongoing developments in the food industry. 展开更多
关键词 Resistant starch Preparation methods Characterization Function Human health
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Development of nontarget method based on GC-QTOF-HRMS for analyzing organic pollutants in human serum 认领 引用 被引量:1
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作者 Congcong Yue Chang He +5 位作者 Hailing Li Zhiquan Yuan Guiying Li Shengtao Ma Xin Zhang Taicheng An 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第7期379-386,共8页
Traditional targeted analyses often overlook unknown or emerging contaminants,highlighting the significance of nontarget and suspect screening approaches.A novel and high-sensitivity methodology for nontarget analysis... Traditional targeted analyses often overlook unknown or emerging contaminants,highlighting the significance of nontarget and suspect screening approaches.A novel and high-sensitivity methodology for nontarget analysis of organic pollutants in human serum was newly-developed based on gas chromatography coupled with quadrupole time-of-flight high-resolution mass spectrometry.The extraction protocol employing an acetonitrile-ethyl acetate(9:1,V:V)mixture significantly improved the extraction efficiency while minimizing matrix effect.A hybridized analytical strategy integrating nontarget and suspect screening was developed to achieve comprehensive identification and classification of pollutants,employing the National Institute of Standards and Technology(NIST)20 library and Agilent Technologies Personal Compound Database and Library(PCDL).This approach successfully characterized 273 organic contaminants spanning 12 categories,including polycyclic aromatic hydrocarbons(PAHs)and their derivatives,esters,and phenolic compounds in human serum,with a significant increase in detection specificity compared to conventional workflows.The methodology used serum samples of the workers from coking industry,revealing widespread contamination dominated by PAHs and PAH derivatives.Among the target analytes,three were identified solely by NIST and six solely by PCDL,indicating the complementary benefits of combining these different databases.Notably,this work reported the first confirmed detection of 2-naphthalenamine in human serum.This optimized approach demonstrates enhanced sensitivity and reliability in serum analysis,advancing biomonitoring capabilities and providing a deep understanding of human exposure to environmental pollutants. 展开更多
关键词 Nontarget analysis Biomonitoring method Human serum sample Organic pollutants GC-QTOF-HRMS
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Antibody screening for tumor and immune hotspot targets:The frontier of new methods and technologies 认领 引用 被引量:1
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作者 Yaping Zhou Yitan Zou +6 位作者 Shaodong Lv Dan Tan Guangyao Li Wenyan Fu Changhai Lei Mingdong Lu Shi Hu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2026年第2期393-412,共20页
Advancements in tumor immunotherapy highlight the significant potential of antibody drugs,a key category of biological agents,for treating cancer and autoimmune diseases.This paper begins by defining and classifying k... Advancements in tumor immunotherapy highlight the significant potential of antibody drugs,a key category of biological agents,for treating cancer and autoimmune diseases.This paper begins by defining and classifying key targets in tumor immunity,as well as discussing their structural and functional characteristics.Subsequently,it elaborates on innovative technologies for antibody drug screening,which,when integrated with contemporary molecular biology,biotechnology,and computational biology,have substantially enhanced the efficiency and accuracy of target identification and antibody drug screening processes.Despite the promising prospects of tumor immunotherapy,certain limitations persist in its practical implementation.In conclusion,this paper offers a comprehensive examination of the cutting-edge developments in tumor immunotherapy,focusing on the aspects of tumor immunotherapy itself,critical targets for immunotherapy,and novel technologies and methodologies for antibody screening.This analysis is crucial for advancing the field of tumor immunotherapy and for enhancing both therapeutic efficacy and safety.Furthermore,research and development(R&D)of antibody drugs in other domains,such as autoimmune and inflammatory diseases,can benefit from it. 展开更多
关键词 Tumor immunotherapy Hotspot targets Antibody drug screening Target discovery Innovative technologies and methods
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Implicit unified gas kinetic particle method for steady-state solution of multiscale phonon transport 认领 引用 被引量:1
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作者 Hongyu Liu Xiaojian Yang +2 位作者 Chuang Zhang Xing Ji Kun Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第2期496-510,共15页
This paper presents a highly efficient implicit unified gas-kinetic particle(IUGKP)method for obtaining steady-state solutions of multi-scale phonon transport.The method adapts and reinterprets the integral solution o... This paper presents a highly efficient implicit unified gas-kinetic particle(IUGKP)method for obtaining steady-state solutions of multi-scale phonon transport.The method adapts and reinterprets the integral solution of the Bhatnagar-Gross-Krook(BGK)equation for time-independent solutions.The distribution function at a given point is determined solely by the surrounding equilibrium states,where the corresponding macroscopic quantities are computed through a weighted sum of equilibrium distribution functions from neighboring spatial positions.From a particle perspective,changes in macroscopic quantities within a cell result from particle transport across cell interfaces.These particles are sampled according to the equilibrium state of their original cells,accounting for their mean free path as the traveling distance.The IUGKP method evolves the solution according to the physical relaxation time scale,achieving high efficiency in large Knudsen number regimes.To accelerate convergence for small Knudsen numbers,an inexact Newton iteration method is implemented,incorporating macroscopic equations for convergence acceleration in the near-diffusive limit.The method also addresses spatial-temporal inconsistency caused by relaxation time variations in physical space through the null-collision concept.Numerical tests demonstrate the method’s excellent performance in accelerating multi-scale phonon transport solutions,achieving speedups of one to two orders of magnitude.The IUGKP method proves to be an efficient and accurate computational tool for simulating multiscale non-equilibrium heat transfer,offering significant advantages over traditional methods in both numerical performance and physical applicability. 展开更多
关键词 Implicit gas kinetic particle method Phonon Boltzmann transport equation Multi-scale heat conduction Steady-state
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A physics-based probabilistic method for assessment of landslide-induced wave run-up hazards 认领 引用 被引量:1
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作者 Ningjie Li Xinli Hu +3 位作者 Jian Wang Junxiang Huang Hongchao Zheng Wei Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第5期3675-3687,共13页
Traditional deterministic numerical simulation often has a poor prediction performance for landslide-induced wave run-up(LIWR)hazards,as it neglects the effects of uncertainty.The limitation for efficiently quantifyin... Traditional deterministic numerical simulation often has a poor prediction performance for landslide-induced wave run-up(LIWR)hazards,as it neglects the effects of uncertainty.The limitation for efficiently quantifying the uncertainties in primary parameters remains largely unsolved.In this study,we propose a probabilistic evaluation method,integrating the adaptive Kriging(AK)metamodel method and probability density evolution method(PDEM)based on generalized F-discrepancy.A Taylor expansion-based adaptive design strategy is applied to construct the global AK model over representative points generated by generalized F-discrepancy,thereby approximating the numerical physical response(i.e.,maximum LIWR).Using these approximate responses,the PDEM is used to compute the exceedance probabilities that LIWR heights exceed elements at risk based on a construction of virtual time,and then a probabilistic criterion is introduced to classify hazard zones.The proposed method is demonstrated via two examples:Example I,which possesses risk element(building),and Example Ⅱ with water-level variations.The results indicate that the proposed method has an acceptable performance(showing a 1.7%difference in exceedance probability compared to Monte Carlo simulation with 50,000 samples)with low computation cost(requiring 284 deterministic analyses).For two specific scenarios in this study,the wave induced by the landslide exhibits a solitary-like leading wave.The proposed probabilistic method provides promising prospects for quantifying LIWR uncertainties,and is helpful for direct,efficient,and low-cost quantification assessment of cascading hazards. 展开更多
关键词 Landslide-induced wave run-up(LIWR) Numerical simulation Adaptive metamodel Probability density evolution method(PDEM) Hazard zoning
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A Comparative Study of State-of-the-Art Meshless Methods for Flow and Transport Simulation in Porous Media 认领 引用
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作者 T.I.Eldho Sanjukta Das +1 位作者 Aatish Anshuman Tinesh Pathania 《Computer Modeling in Engineering & Sciences》 SCIE EI 2026年第5期828-852,共25页
In recent years,meshless methods have been increasingly applied to the simulation of various engineering problems due to their inherent advantages over traditional mesh-based approaches,including greater flexibility,i... In recent years,meshless methods have been increasingly applied to the simulation of various engineering problems due to their inherent advantages over traditional mesh-based approaches,including greater flexibility,independence from predefined meshing,simpler adaptive analysis,improved automation,and suitability for complex problems.Several meshless methods have been used for porous media simulation,and are broadly categorized into collocation,global weak form and local weak form methods.In this study,a comprehensive comparison of the applicability of these three categories of meshless methods for simulating coupled flow and transport problems in porous media is presented.The Radial Point Collocation Method(RPCM)(strong form),the Element Free Galerkin Method(EFGM)(global weak form)and the Meshless Local Petrov Galerkin(MLPG)method(local weak form)are implemented and systematically compared.These methods are applied to the analysis of flow in a synthetic regular domain aquifer,flow and non-reactive contaminant transport in a synthetic irregular boundary porous media problem and groundwater flow in a field aquifer located in India.The simulated groundwater heads are compared with analytical solution,observed field data and results obtained from widely used MODFLOW-MT3DMS models.The deviation of the solutions from the analytical solution is in the range of O.67%to O.l6%for the hypothetical case study.For the field-scale case study,mean absolute error of 0.183%,0.18l%and 0.188%are obtained for the RPCM,EFGM and MLPG models,respectively,outperforming MODFLOW,which exhibits a deviation of 0.254%from observed values.Overall,the present study reaffirms the practical applicability of these meshless methods for real-world groundwater problems and provides valuable insights into the utilization of each category of meshless method,with respect to problem type,computational efficiency and accuracy requirements. 展开更多
关键词 Meshless methods groundwater flow contaminant transport radial point collocation method element free Galerkin method meshless local Petrov Galerkin method
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A Review on Circumferential Crack Method Used for Simulating Ice-Structure Interaction 认领 引用 被引量:3
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作者 ZHOU Li 《China Ocean Engineering》 SCIE EI CSCD 2026年第1期1-14,共14页
Structure-ice interaction problems have attracted increasing attention,yet accurately predicting the loads exerted by sea ice on ship hulls remains a significant challenge.Over the past few decades,various numerical m... Structure-ice interaction problems have attracted increasing attention,yet accurately predicting the loads exerted by sea ice on ship hulls remains a significant challenge.Over the past few decades,various numerical methods have been employed to simulate ice resistance on ships and evaluate their manoeuvrability during ice-structure interaction.Among these approaches,the circumferential crack method has demonstrated both high efficiency and accuracy.This paper provides a detailed introduction to the fundamental theory of this method,including the numerical modeling of different failure modes and the dynamic ice motion responses.Furthermore,it reviews existing studies on predicting ice resistance and assessing the manoeuvrability of icebreakers navigating through ice-covered regions using the circumferential crack method.Several recommendations for future research in this field are also presented. 展开更多
关键词 ice forces circumferential crack method ice resistance ice-structure interaction ice failure modes polar ship
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Tunnel ahead prospecting methods and intelligent interpretation of adverse geology:A review 认领 引用 被引量:1
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作者 Shucai Li Bin Liu +4 位作者 Lei Chen Huaifeng Sun Lichao Nie Zhengyu Liu Yuxiao Ren 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第1期1-19,共19页
Geological prospecting and the identification of adverse geological features are essential in tunnel construction,providing critical information to ensure safety and guide engineering decisions.As tunnel projects exte... Geological prospecting and the identification of adverse geological features are essential in tunnel construction,providing critical information to ensure safety and guide engineering decisions.As tunnel projects extend into deeper and more mountainous terrains,engineers face increasingly complex geological conditions,including high water pressure,intense geo-stress,elevated geothermal gradients,and active fault zones.These conditions pose substantial risks such as high-pressure water inrush,largescale collapses,and tunnel boring machine(TBM)blockages.Addressing these challenges requires advanced detection technologies capable of long-distance,high-precision,and intelligent assessments of adverse geology.This paper presents a comprehensive review of recent advancements in tunnel geological ahead prospecting methods.It summarizes the fundamental principles,technical maturity,key challenges,development trends,and real-world applications of various detection techniques.Airborne and semi-airborne geophysical methods enable large-scale reconnaissance for initial surveys in complex terrain.Tunnel-and borehole-based approaches offer high-resolution detection during excavation,including seismic ahead prospecting(SAP),TBM rock-breaking source seismic methods,fulltime-domain tunnel induced polarization(TIP),borehole electrical resistivity,and ground penetrating radar(GPR).To address scenarios involving multiple,coexisting adverse geologies,intelligent inversion and geological identification methods have been developed based on multi-source data fusion and artificial intelligence(AI)techniques.Overall,these advances significantly improve detection range,resolution,and geological characterization capabilities.The methods demonstrate strong adaptability to complex environments and provide reliable subsurface information,supporting safer and more efficient tunnel construction. 展开更多
关键词 Tunnel geological ahead prospecting Complex geological and environmental conditions Airborne geophysical methods Tunnel geophysical detection Borehole geophysical prospecting Intelligent geological interpretation
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Investigation of dynamic seismic response in liquid-containing structures for nuclear reactors using the hybrid Eulerian-Lagrangian method 认领 引用
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作者 Shi-Lin Chen Qing-Xi Yang +3 位作者 Qing-Zhou Yu Hao Xu Jian Chen Zhao-Xi Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第6期159-177,共19页
Liquid-containing structures,including steam generators,water-cooling systems,in-containment refueling water storage tanks,suppression tanks,and tritiated water storage facilities,are integral components of nuclear re... Liquid-containing structures,including steam generators,water-cooling systems,in-containment refueling water storage tanks,suppression tanks,and tritiated water storage facilities,are integral components of nuclear reactor systems and are crucial for ensuring operational safety and stability.Traditional seismic analysis methods often struggle to accurately predict the dynamic behavior of such structures,particularly under transient events such as earthquakes.This paper presents a comprehensive study that applies the hybrid Eulerian-Lagrangian method to analyze fluid-structure interactions within these structures.The efficacy of this method for capturing the complex dynamics induced by liquid movement is demonstrated through simulations conducted primarily in a vertical storage tank.A comparative analysis with traditional response-spectrum analysis methods underscores the limitations of conventional approaches,particularly in terms of accounting for nonlinear free-surface motions and dynamic velocity distributions.The structural response of the tank containing liquid calculated using the hybrid Eulerian-Lagrangian method is approximately twice that calculated using the response-spectrum method,whereas in the case of a tank without liquid,the response is the same.Additionally,a high dynamic stress distribution exists near the liquid level of the structure.This study addresses the intricate interplay between structural components and fluid dynamics,thereby extrapolating insights from tanks to enhance safety protocols and design considerations for future nuclear devices. 展开更多
关键词 Liquid-containing structures Nuclear reactors Seismic analysis methods Hybrid Euler-Lagrangian method Complex dynamics
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Comparison and applications of solid weighting functions for fluid-particle modeling using the lattice Boltzmann-discrete element coupling method 认领 引用
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作者 Duo Wang Yuman Han +5 位作者 Yi Zheng Songyan Wang Xiaofang Jiang Shiyi Jiang Mengdi Sun Zhejun Pan 《Theoretical & Applied Mechanics Letters》 EI CAS CSCD 2026年第3期73-82,共10页
This paper presents a comparative study of the solid weighting functions within the text of the modified partially saturated method(MPSM),which is an effective fluid-solid boundary condition in the lattice Boltzmann-d... This paper presents a comparative study of the solid weighting functions within the text of the modified partially saturated method(MPSM),which is an effective fluid-solid boundary condition in the lattice Boltzmann-discrete element coupling method(LBM-DEM).In its original form,the solid weighting function is τ-dependent.Previous studies have shown that the computational drag is viscosity-dependent when using the τ-dependent solid weighting function to solve fluid-particle interactions.To address this issue,two modified solid weighting functions,namely,the higher-order function and the solid-coverage function,are proposed.Nevertheless,the literature lacks a comparison of these functions,especially for viscosity dependence.In this study,the solid weighting functions are implemented and tested through two benchmark multiphase configurations,i.e.,a sphere settling between two parallel plates and the‘drafting,kissing and tumbling’of two settling spheres.The computational accuracy,viscosity dependence and convergence of the two modified functions are validated and compared against the original τ-dependent function.The LBM-DEM-MPSM formulation is then applied to study the settling behavior of a particle pack with varying solid fractions in a narrow fracture,which highlights the potential of employing the LBM-DEM-MPSM approach to a broader range of fluid-particle systems. 展开更多
关键词 Lattice boltzmann method Discrete element method Fluid-solid boundary conditions Fluid-particle interaction particle settling
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Moment flux-based discrete velocity method based on the Boltzmann-BGK equations along the characteristic line 认领 引用
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作者 Wei Liu Yong Liu Haihu Liu 《Theoretical & Applied Mechanics Letters》 EI CAS CSCD 2026年第3期110-120,共11页
This paper introduces an improved scheme based on the discrete velocity method.Specifically,the reconstruction of the velocity distribution function and numerical flux at the interface is founded on the solution of th... This paper introduces an improved scheme based on the discrete velocity method.Specifically,the reconstruction of the velocity distribution function and numerical flux at the interface is founded on the solution of the Bhatnagar-Gross-Krook equation along the characteristic line.The proposed method accurately considers molecular transport and collision effects at the interface,thereby enabling accurate modeling from rarefied to continuum flow regimes.Additionally,the implicit discretization of the microscopic equations and incorporation of macroscopic equations result in accelerated convergence properties for steady-state problems.The proposed numerical approach is validated through several cases,including Rayleigh flow,lid-driven cavity flow,flow past an NACA0012 airfoil,and supersonic flow around a sphere.Numerical results demonstrate that the proposed method can efficiently and accurately obtain multiscale flow properties. 展开更多
关键词 Rarefied flow Boltzmann equation Moment method Finite volume method
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The order of accuracy related to the error from source approximation in the method of characteristics for purely absorbing materials in planar geometry 认领 引用
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作者 Ji-Pu Wang Zhen-Wen Wei +5 位作者 Can Huang William Martin Brendan Kochunas Qi-Cang Shen Si-Juan Chen Martin Pilch 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第6期257-270,共14页
The method of characteristics(MoC)is a well-established tool for lattice physics calculations,offering advantages such as accurate representation of both lattice geometry and boundary conditions.The flat source(FS)app... The method of characteristics(MoC)is a well-established tool for lattice physics calculations,offering advantages such as accurate representation of both lattice geometry and boundary conditions.The flat source(FS)approximation is the most commonly used approach,whereas the linear source(LS)approximation enhances the accuracy by preserving the higherorder spatial moments of the neutron source.However,determining the order of accuracy(OoA)for spatial discretization in the MoC is challenging,particularly for the LS approximation.This complexity arises because MoC employs two spatial meshes:the fission source region(FSR)mesh and a set of characteristic rays used to integrate the transport equation over the FSR mesh.In this study,we analyzed the spatial order of accuracy of the MoC in planar geometry for both FS and LS approximations in relation to the distributed source.Our theoretical predictions are consistent with the numerical results obtained using the Method of Manufactured Solutions(MMS).The results demonstrate that the FS approximation achieves second-order accuracy,whereas the LS approximation attains fourth-order accuracy. 展开更多
关键词 Method of characteristics Order of accuracy Flat source approximation Linear source approximation Method of manufactured solutions
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Development of an intelligent drilling cuttings method drill rig for addressing suction and sticking phenomena:Field experiment 认领 引用
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作者 Lei Cui Yishan Pan +4 位作者 Jianzuo Zhang Aiwen Wang Lianpeng Dai Cancan Liu Shengliang Lu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2026年第6期1189-1202,共14页
During the operation of the drilling cuttings method,frequent occurrences of suction and sticking phenomena lead to the loss of drilling tools and failure to achieve the designed borehole depth.resulting in inaccurate... During the operation of the drilling cuttings method,frequent occurrences of suction and sticking phenomena lead to the loss of drilling tools and failure to achieve the designed borehole depth.resulting in inaccurate risk assessment for coal seam rockbursts.To address these challenges,a mechanical analysis of cuttings transport via the spiral drill pipe was conducted.This analysis identified the primary factors contributing to suction and sticking phenomena in spiral drill pipes and proposed a targeted approach for mitigating these issues.Based on this analysis,an intelligent drilling cuttings method drill rig(IDCMDR)was developed,and field experiments were conducted.The experimental results demonstrate that when suction occurs,adjusting the rotational and drilling speeds of the IDCMDR effectively controls the phenomenon.When sticking occurs,the stuck drill pipe can be addressed by injecting high-pressure gas into the borehole bottom through the hollow structure of the spiral drill pipe or by reversing its rotation.During operation,characteristic patterns in the needle movements of the thrust and torque hydraulic gauges on the IDCMDR enable the identification of suction and sticking phenomena.The development and field validation of the IDCMDR confirm the feasibility of the theoretically proposed mitigation methods. 展开更多
关键词 Rockburst Drilling cuttings method Intelligent drilling cuttings method drill rig (IDCMDR) Spiral drill pipe Suction and sticking phenomena
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