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Multiple-stage dynamic responses and failure behaviors of surrounding rocks subjected to development blasting: Exponential and triangular paths
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作者 Siyu Peng Xibing Li +1 位作者 Yasuhiro Mitani Jingyao Gao 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第6期3773-3789,共17页
During the development blasting of circular tunnels, the detonation of multiple blastholes arranged onconcentric circles induces a complex dynamic response in the surrounding rocks. This process involvesmultiple blast... During the development blasting of circular tunnels, the detonation of multiple blastholes arranged onconcentric circles induces a complex dynamic response in the surrounding rocks. This process involvesmultiple blast loadings, static stress unloadings, and stress redistributions. In this study, the dynamicstresses of the surrounding rocks during development blasting, considering multiple blasting-unloadingstages with exponential paths and triangular paths (linear simplified paths of exponential paths), aresolved based on the dynamic theory and the Fourier transform method. Then, a corresponding discreteelement model is established using particle flow code (PFC). The multiple-stage dynamic stress andfracture distribution under different in situ stress levels and lateral coefficients are investigated. Theoreticalresults indicate that the peak compressive stresses in the surrounding rocks induced by bothtriangular and exponential paths are equal, while the triangular path generates greater additional dynamictensile stresses, particularly in the circumferential direction, compared to the exponential path.Numerical results show that the exponential path causes less dynamic circumferential tensile damageand forms fewer radial fractures than the triangular path in the first few blast stages;conversely, itexacerbates the damage and instability in the final blasting-unloading stage and forms more circumferentialfractures. Furthermore, the in situ stress determines which of the two opposite effects isdominant. Therefore, when using overly simplified triangular paths to evaluate the stability of surroundingrocks, potential overestimation or underestimation caused by different failure mechanismsshould be considered. Specifically, under high horizontal and vertical stresses, the static stress redistributionwith layer-by-layer blasting suppresses dynamic circumferential tensile and radial compressivedamage. The damage evolution of surrounding rocks in multi-stage blasting under different in situstresses is summarized and classified according to the damage mechanism and characteristics, which canguide blasting and support design. 展开更多
关键词 Development blasting multiple blast stages In situ stress Lateral stress coefficient Blasting-unloading path
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Spatial heterogeneity of groundwater depths in coastal cities and their responses to multiple factors interactions by interpretable machine learning models
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作者 Yuming Mo Jing Xu +5 位作者 Senlin Zhu Beibei Xu Jinran Wu Guangqiu Jin You-Gan Wang Ling Li 《Geoscience Frontiers》 2025年第3期223-241,共19页
Understanding spatial heterogeneity in groundwater responses to multiple factors is critical for water resource management in coastal cities.Daily groundwater depth(GWD)data from 43 wells(2018-2022)were collected in t... Understanding spatial heterogeneity in groundwater responses to multiple factors is critical for water resource management in coastal cities.Daily groundwater depth(GWD)data from 43 wells(2018-2022)were collected in three coastal cities in Jiangsu Province,China.Seasonal and Trend decomposition using Loess(STL)together with wavelet analysis and empirical mode decomposition were applied to identify tide-influenced wells while remaining wells were grouped by hierarchical clustering analysis(HCA).Machine learning models were developed to predict GWD,then their response to natural conditions and human activities was assessed by the Shapley Additive exPlanations(SHAP)method.Results showed that eXtreme Gradient Boosting(XGB)was superior to other models in terms of prediction performance and computational efficiency(R^(2)>0.95).GWD in Yancheng and southern Lianyungang were greater than those in Nantong,exhibiting larger fluctuations.Groundwater within 5 km of the coastline was affected by tides,with more pronounced effects in agricultural areas compared to urban areas.Shallow groundwater(3-7 m depth)responded immediately(0-1 day)to rainfall,primarily influenced by farmland and topography(slope and distance from rivers).Rainfall recharge to groundwater peaked at 50%farmland coverage,but this effect was suppressed by high temperatures(>30℃)which intensified as distance from rivers increased,especially in forest and grassland.Deep groundwater(>10 m)showed delayed responses to rainfall(1-4 days)and temperature(10-15 days),with GDP as the primary influence,followed by agricultural irrigation and population density.Farmland helped to maintain stable GWD in low population density regions,while excessive farmland coverage(>90%)led to overexploitation.In the early stages of GDP development,increased industrial and agricultural water demand led to GWD decline,but as GDP levels significantly improved,groundwater consumption pressure gradually eased.This methodological framework is applicable not only to coastal cities in China but also could be extended to coastal regions worldwide. 展开更多
关键词 Groundwater depth Spatial heterogeneity multiple influence factorsCoastal cities Machine Learning models SHAP values
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Cooperative robust parallel operation of multiple actuators
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作者 XU Liang XU Xiang LIU Tao 《控制理论与应用》 北大核心 2026年第1期3-11,共9页
This paper studies cooperative robust parallel operation of multiple actuators over an undirected communication graph.The plant is modeled as an uncertain linear system,and the actuators are linear and identical.Based... This paper studies cooperative robust parallel operation of multiple actuators over an undirected communication graph.The plant is modeled as an uncertain linear system,and the actuators are linear and identical.Based on the internal model principle,a distributed dynamic output feedback control law is proposed to achieve both robust output regulation of the closed-loop system and plant input sharing among the actuators.A practical example of five motors cooperatively driving an uncertain shaft under an external load torque is presented to show the effectiveness of the proposed control law. 展开更多
关键词 cooperative parallel operation multiple actuators robust output regulation CONSENSUS
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Illusion of inactivity:Revisiting progressive multiple sclerosis treatment paradigms
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作者 Tal Ganz Tamir Ben-Hur 《Neural Regeneration Research》 2026年第3期1134-1135,共2页
Active inflammation in“inactive”progressive multiple sclerosis:Traditionally,the distinction between relapsing-remitting multiple sclerosis and progressive multiple sclerosis(PMS)has been framed as an inflammatory v... Active inflammation in“inactive”progressive multiple sclerosis:Traditionally,the distinction between relapsing-remitting multiple sclerosis and progressive multiple sclerosis(PMS)has been framed as an inflammatory versus degenerative dichotomy.This was based on a broad misconception regarding essentially all neurodegenerative conditions,depicting the degenerative process as passive and immune-independent occurring as a late byproduct of active inflammation in the central nervous system(CNS),which is(solely)systemically driven. 展开更多
关键词 inflammatory versus degenerative dichotomythis treatment paradigms illusion inactivity multiple sclerosis traditionallythe central nervous system cns which progressive multiple sclerosis active inflammation progressive multiple sclerosis pms
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Predicting lymph node metastasis in colorectal cancer using caselevel multiple instance learning
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作者 Ling-Feng Zou Xuan-Bing Wang +4 位作者 Jing-Wen Li Xin Ouyang Yi-Ying Luo Yan Luo Cheng-Long Wang 《World Journal of Gastroenterology》 2026年第1期110-125,共16页
BACKGROUND The accurate prediction of lymph node metastasis(LNM)is crucial for managing locally advanced(T3/T4)colorectal cancer(CRC).However,both traditional histopathology and standard slide-level deep learning ofte... BACKGROUND The accurate prediction of lymph node metastasis(LNM)is crucial for managing locally advanced(T3/T4)colorectal cancer(CRC).However,both traditional histopathology and standard slide-level deep learning often fail to capture the sparse and diagnostically critical features of metastatic potential.AIM To develop and validate a case-level multiple-instance learning(MIL)framework mimicking a pathologist's comprehensive review and improve T3/T4 CRC LNM prediction.METHODS The whole-slide images of 130 patients with T3/T4 CRC were retrospectively collected.A case-level MIL framework utilising the CONCH v1.5 and UNI2-h deep learning models was trained on features from all haematoxylin and eosinstained primary tumour slides for each patient.These pathological features were subsequently integrated with clinical data,and model performance was evaluated using the area under the curve(AUC).RESULTS The case-level framework demonstrated superior LNM prediction over slide-level training,with the CONCH v1.5 model achieving a mean AUC(±SD)of 0.899±0.033 vs 0.814±0.083,respectively.Integrating pathology features with clinical data further enhanced performance,yielding a top model with a mean AUC of 0.904±0.047,in sharp contrast to a clinical-only model(mean AUC 0.584±0.084).Crucially,a pathologist’s review confirmed that the model-identified high-attention regions correspond to known high-risk histopathological features.CONCLUSION A case-level MIL framework provides a superior approach for predicting LNM in advanced CRC.This method shows promise for risk stratification and therapy decisions,requiring further validation. 展开更多
关键词 Colorectal cancer Lymph node metastasis Deep learning multiple instance learning HISTOPATHOLOGY
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Formation control for multiple spacecraft with disturbances and sensor failures
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作者 Yufei LYU Yuezu PENG Wenliang 《Journal of Systems Engineering and Electronics》 2026年第1期18-25,共8页
Formation control of multiple spacecraft has attracted extensive research attention.However,achieving reliable performance under sensor failures remains a significant challenge.This paper develops an integrated framew... Formation control of multiple spacecraft has attracted extensive research attention.However,achieving reliable performance under sensor failures remains a significant challenge.This paper develops an integrated framework that jointly designs distributed observers and local controllers to ensure robust formation control in the presence of external disturbances and sensor malfunctions.Treating the spacecraft formation as a single interconnected system,each spacecraft constructs a distributed observer that estimates the overall system state by incorporating both its own measurements and the predicted control information shared among the spacecraft.Based on the observer estimates,a local control law is synthesized to maintain the desired formation.Rigorous theoretical analysis and numerical simulations demonstrate that the proposed integrated approach effectively guarantees formation stability and resilience against sensor failures and disturbances. 展开更多
关键词 formation control multiple spacecraft DISTURBANCE sensor failure
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Retinal layers thickness and retinal vascular parameters in patients with multiple sclerosis
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作者 Mehdi Moghaddasi Mahsa Sardarinia +3 位作者 Mostafa Soltansanjari Ahmad Vafajoo Nafise Mohebi Simin Zare 《国际眼科杂志》 2026年第3期368-374,共7页
AIM:To investigate the changes of retinal vascular parameters and retinal layer thickness in patients with multiple sclerosis(MS).METHODS:This single-centered case-control study was performed on a MS group of 42 patie... AIM:To investigate the changes of retinal vascular parameters and retinal layer thickness in patients with multiple sclerosis(MS).METHODS:This single-centered case-control study was performed on a MS group of 42 patients diagnosed with MS and a control group of 43 healthy hospital staff matched in terms of age and sex at Iran University,department of neurology and ophthalmology from March 2020 to March 2021.The ophthalmic parameters of each patient were recorded,and optical coherence tomography was used to evaluate the retinal thickness in the layers.RESULTS:This study enrolled a total of 85 participants,with a mean age of 40.44±11.52 years,including 61 females(72%).The control group consisted of 43 individuals with a mean age of 39.49±11.07 years,while the MS group comprised 42 participants with a mean age of 41.40±12.01 years.The mean disease duration in the MS group was 8.45±6.04 a.The thickness of the ganglion cell layer in the right eye was significantly lower in the MS group compared to the control group(P=0.034).In addition,except for the left nasal sector(P=0.106),the mean peripapillary neurofibrillation in all examined sectors were significantly lower in the MS group than in the control group(P<0.05).The average vessel density in both the deep and superficial capillary plexuses across all regions of both eyes was lower in the MS group than in the control group,with all comparisons for the superficial capillary plexus showing statistical significance(P<0.05 for all except the left nasal sector).CONCLUSION:The thickness of the retina of patients with MS is significantly reduced.Therefore,optical coherence tomography results can be used as a reliable tool to evaluate disease progression and prognosis in MS patients. 展开更多
关键词 multiple sclerosis optical coherence tomography RETINA retinal vascular disorder retinal layer thickness
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Multi-Area Path Planning for Multiple Unmanned Surface Vessels
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作者 Jianing Wu Yufeng Chen +2 位作者 Li Yin Huajun He Panshuan Jin 《Computers, Materials & Continua》 2026年第4期1093-1110,共18页
To conduct marine surveys,multiple unmanned surface vessels(Multi-USV)with different capabilities perform collaborative mapping in multiple designated areas.This paper proposes a task allocation algorithm based on int... To conduct marine surveys,multiple unmanned surface vessels(Multi-USV)with different capabilities perform collaborative mapping in multiple designated areas.This paper proposes a task allocation algorithm based on integer linear programming(ILP)with flow balance constraints,ensuring the fair and efficient distribution of sub-areas among USVs and maintaining strong connectivity of assigned regions.In the established gridmap,a search-based path planning algorithm is performed on the sub-areas according to the allocation scheme.It uses the greedy algorithm and the A*algorithm to achieve complete coverage of the barrier-free area and obtain an efficient trajectory of each USV.The greedy algorithm enables fast local traversal of unvisited grids,while the A*algorithm ensures navigation to escape from deadlock areas and maintains global path continuity.The comparison of task allocation results proves that the task allocation algorithm based on ILP improves the mapping efficiency and task distribution fairness.The proposed allocation method and result analysis provide a certain reference for the practical application ofMulti-USV to perform survey tasks collaboratively. 展开更多
关键词 multiple unmanned surface vessels multiple areas integer linear programming
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Effects of Lycium barbarum polysaccharide on the activation of pathogenic CD4^(+)T cells in a mouse model of multiple sclerosis
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作者 Mengdi Guo Guozhen Deng +9 位作者 Bin Huang Zhiyong Lin Xue Yang Linglin Dong Zilin Wang Yi Guo Ming Yi Weiyan Wang Mei-Ling Jiang Cun-Jin Zhang 《Neural Regeneration Research》 2026年第6期2563-2572,共10页
Multiple sclerosis is a severe autoimmune disorder that is mainly mediated by pathogenic cluster of CD4^(+)T cell subsets.Despite advancements in the management of multiple sclerosis,there is a critical need for more ... Multiple sclerosis is a severe autoimmune disorder that is mainly mediated by pathogenic cluster of CD4^(+)T cell subsets.Despite advancements in the management of multiple sclerosis,there is a critical need for more effective and safer treatments.In the present study,we administered Lycium barbarum glycopeptide to a mouse model of experimental autoimmune encephalomyelitis-an animal model of multiple sclerosis-and evaluated its effects on pathogenic CD4^(+)T cell activation both in vivo and in vitro.Lycium barbarum glycopeptide significantly mitigated the clinical severity of experimental autoimmune encephalomyelitis,as demonstrated by reduced demyelination and neuroinflammation.Moreover,Lycium barbarum glycopeptide treatment decreased the infiltration of peripheral leukocytes into the central nervous system and suppressed pro-inflammatory cytokine expression.Lycium barbarum glycopeptide also modulated pathogenic CD4^(+)T cell activation by inhibiting T helper 1/T helper 17 cell differentiation while promoting regulatory T cell expansion.Notably,no side effects were observed,suggesting the long-term safety and tolerability of Lycium barbarum glycopeptide.Furthermore,RNA sequencing data indicated that Lycium barbarum glycopeptide inhibits activator protein-1,an essential regulator of T cell activation and differentiation.This finding was supported by the reversal of T helper/T helper 17 cell response suppression upon AP-1 blockade.Collectively,these results highlight the potential of Lycium barbarum glycopeptide as an innovative therapeutic agent for CD4^(+)T cell-associated autoimmune or inflammatory diseases,such as multiple sclerosis. 展开更多
关键词 AP-1 signaling pathway experimental autoimmune encephalomyelitis Lycium barbarum glycopeptide multiple sclerosis neuroinflammation nucelar factor-κB signaling pathway NLRP3 inflammasome pathogenic CD4^(+)T cells T helper 1/T helper 17 cell differentiation Treg polarization
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Implementation of a multiple round quantum dense coding using nuclear magnetic resonance 被引量:8
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作者 ZHANG Jingfu XIE Jingyi +3 位作者 WANG Chuan DENG Zhiwei LU Zhiheng LONG Guilu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2005年第6期706-715,共10页
A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance(NMR)quantum computer.Using an m+1 qubit system,Bob c... A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance(NMR)quantum computer.Using an m+1 qubit system,Bob can transmit one of 2m+1 messages to Alice,through manipulating only one qubit and exchanging it between Alice and Bob for m rounds.The information capacity is enhanced to m+1 bits as compared to m bits in a classical scheme.The scheme has been demonstrated in NMR system,and the experimental results show a good agreement between theory and experiment. 展开更多
关键词 quantum dense coding multiple round nuclear magnetic resorance
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Development of a multiple level underground limestone mine from geology through mine planning 被引量:3
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作者 Christopher Newman David Newman Robert Dupuy 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第1期63-67,共5页
The development of a multiple level underground mine is a complex task in which geology,engineering,ground control,and unit operations are integrated into a single mine design.The components are interdependent and mus... The development of a multiple level underground mine is a complex task in which geology,engineering,ground control,and unit operations are integrated into a single mine design.The components are interdependent and must function cohesively to ensure a profitable underground mining operation.To optimize reserve recovery,mine planning should begin from the lowest level and progress up.This limits any misjudgments or oversights of a given level affecting the underlying levels and ensures the ability to maximize recovery from each level.Mine planning should start with the exploration and characterization of the geologic setting.Once the reserve geology and quality is well understood,then mine planning can begin with respect to the following:(1)orientation of mine works with respect to horizontal stress;(2)access to the reserve;(3)determination of opening widths;(4)selection of back,floor horizons and pillar centers;(5)selection of development and secondary mining heights;(6)appropriate inter-burden thicknesses;and(7)examining the stability of the multiple level mine through numerical modeling.The multiple level mine design process and decisions are presented through a case history example.The theme is that there is one opportunity to"get it right"and many chances to overlook a small aspect within the design that will plague the mine throughout all levels and through the entirety of its operating life. 展开更多
关键词 LIMESTONE MINE planning GEOLOGY multiple LEVEL Rock mechanics
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Inclusive Multiple Models(IMM)for predicting groundwater levels and treating heterogeneity 被引量:2
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作者 Rahman Khatibi Ata Allah Nadiri 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第2期713-724,共12页
An explicit model management framework is introduced for predictive Groundwater Levels(GWL),particularly suitable to Observation Wells(OWs)with sparse and possibly heterogeneous data.The framework implements Multiple ... An explicit model management framework is introduced for predictive Groundwater Levels(GWL),particularly suitable to Observation Wells(OWs)with sparse and possibly heterogeneous data.The framework implements Multiple Models(MM)under the architecture of organising them at levels,as follows:(i)Level 0:treat heterogeneity in the data,e.g.Self-Organised Mapping(SOM)to classify the OWs;and decide on model structure,e.g.formulate a grey box model to predict GWLs.(ii)Level 1:construct MMs,e.g.two Fuzzy Logic(FL)and one Neurofuzzy(NF)models.(iii)Level 2:formulate strategies to combine the MM at Level 1,for which the paper uses Artificial Neural Networks(Strategy 1)and simple averaging(Strategy 2).Whilst the above model management strategy is novel,a critical view is presented,according to which modelling practices are:Inclusive Multiple Modelling(IMM)practices contrasted with existing practices,branded by the paper as Exclusionary Multiple Modelling(EMM).Scientific thinking over IMMs is captured as a framework with four dimensions:Model Reuse(MR),Hierarchical Recursion(HR),Elastic Learning Environment(ELE)and Goal Orientation(GO)and these together make the acronym of RHEO.Therefore,IMM-RHEO is piloted in the aquifer of Tabriz Plain with sparse and possibly heterogeneous data.The results provide some evidence that(i)IMM at two levels improves on the accuracy of individual models;and(ii)model combinations in IMM practices bring‘model-learning’into fashion for learning with the goal to explain baseline conditions and impacts of subsequent management changes. 展开更多
关键词 Artificial intelligence Exclusionary multiple modelling(EMM) Groundwater level prediction Inclusive multiple modelling(IMM) Model management practices
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Hydrodynamic Behavior of Gap Resonance in Multiple-Box Systems with Sharp and Round Inlet Configurations 被引量:2
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作者 RAN Ya-qing JIANG Sheng-chao +1 位作者 GENG Bao-lei JIN Rui-jia 《China Ocean Engineering》 SCIE EI CSCD 2023年第5期849-862,共14页
Fluid resonance within narrow gaps in multiple-box systems with sharp and round inlet configurations are investigated by using the potential flow and viscous fluid flow models in the OpenFOAM^(■)package.Evident discr... Fluid resonance within narrow gaps in multiple-box systems with sharp and round inlet configurations are investigated by using the potential flow and viscous fluid flow models in the OpenFOAM^(■)package.Evident discrepancy between two numerical models can be observed for sharp inlet configurations.In addition to the dramatical decrease of resonant amplitude in narrow gaps,some peak values at the higher resonant frequencies predicted by the potential flow model even disappear in the viscous fluid flow results.The decreased normalized resonant amplitudes with the increase of incident wave amplitude can be observed for sharp inlet configurations.However,the hydrodynamic behaviors of multiple-box system with round inlet configurations between potential flow and viscous fluid flow models are quite similar with each other.The normalized resonant amplitudes are nearly independent of incident wave amplitudes for multiple-box systems with round inlet configurations.This implies that the energy dissipation associated with fluid viscosity and flow rotation plays an important role in the gap resonance for sharp inlet configurations;while it is insignificant for round inlet configurations. 展开更多
关键词 fluid resonance multiple boxes sharp edge round edge OpenFOAM
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Nearest neighbor search algorithm based on multiple background grids for fluid simulation 被引量:2
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作者 郑德群 武频 +1 位作者 尚伟烈 曹啸鹏 《Journal of Shanghai University(English Edition)》 CAS 2011年第5期405-408,共4页
The core of smoothed particle hydrodynamics (SPH) is the nearest neighbor search subroutine. In this paper, a nearest neighbor search algorithm which is based on multiple background grids and support variable smooth... The core of smoothed particle hydrodynamics (SPH) is the nearest neighbor search subroutine. In this paper, a nearest neighbor search algorithm which is based on multiple background grids and support variable smooth length is introduced. Through tested on lid driven cavity flow, it is clear that this method can provide high accuracy. Analysis and experiments have been made on its parallelism, and the results show that this method has better parallelism and with adding processors its accuracy become higher, thus it achieves that efficiency grows in pace with accuracy. 展开更多
关键词 multiple background grids smoothed particle hydrodynamics (SPH) nearest neighbor search algorithm parallel computing
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Prediction of cavity growth rate during underground coal gasification using multiple regression analysis 被引量:12
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作者 Mehdi Najafi Seyed Mohammad Esmaiel Jalali +1 位作者 Reza KhaloKakaie Farrokh Forouhandeh 《International Journal of Coal Science & Technology》 EI 2015年第4期318-324,共7页
During underground coal gasification (UCG), whereby coal is converted to syngas in situ, a cavity is formed in the coal seam. The cavity growth rate (CGR) or the moving rate of the gasification face is affected by... During underground coal gasification (UCG), whereby coal is converted to syngas in situ, a cavity is formed in the coal seam. The cavity growth rate (CGR) or the moving rate of the gasification face is affected by controllable (operation pressure, gasification time, geometry of UCG panel) and uncontrollable (coal seam properties) factors. The CGR is usually predicted by mathematical models and laboratory experiments, which are time consuming, cumbersome and expensive. In this paper, a new simple model for CGR is developed using non-linear regression analysis, based on data from 1 l UCG field trials. The empirical model compares satisfactorily with Perkins model and can reliably predict CGR. 展开更多
关键词 Underground coal gasification (UCG) - Cavity growth rate . multiple regression analysis ~ Empirical model
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New empirical model to evaluate groundwater flow into circular tunnel using multiple regression analysis 被引量:6
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作者 Farhadian Hadi Katibeh Homayoon 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第3期415-421,共7页
There are various analytical, empirical and numerical methods to calculate groundwater inflow into tun- nels excavated in rocky media. Analytical methods have been widely applied in prediction of groundwa- ter inflow ... There are various analytical, empirical and numerical methods to calculate groundwater inflow into tun- nels excavated in rocky media. Analytical methods have been widely applied in prediction of groundwa- ter inflow to tunnels due to their simplicity and practical base theory. Investigations show that the real amount of water infiltrating into jointed tunnels is much less than calculated amount using analytical methods and obtained results are very dependent on tunnel's geometry and environmental situations. In this study, using multiple regression analysis, a new empirical model for estimation of groundwater seepage into circular tunnels was introduced. Our data was acquired from field surveys and laboratory analysis of core samples. New regression variables were defined after perusing single and two variables relationship between groundwater seepage and other variables. Finally, an appropriate model for estima- tion of leakage was obtained using the stepwise algorithm. Statistics like R, R2, R2e and the histogram of residual values in the model represent a good reputation and fitness for this model to estimate the groundwater seepage into tunnels. The new experimental model was used for the test data and results were satisfactory. Therefore, multiple regression analysis is an effective and efficient way to estimate the groundwater seeoage into tunnels. 展开更多
关键词 Groundwater inflow Analytical equation multiple regression analysis Stepwise algorithm Tunnel
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Boundary Element Analysis (Laplace Transform Solution) of Groundwater Unsteady Flow to a Multiple Well System in a Confined Aquifer 被引量:1
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作者 Zhu Xueyu Xie Chunhong Zou Zeyuan Nanjing University, Nanjing, Jiangsu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1990年第1期93-99,共7页
The calculations of unsteady flow to a multiple well system with the application of boundary elementmethod (BEM) are discussed. The mathematical model of unsteady well flow is a boundary value problem ofparabolic diff... The calculations of unsteady flow to a multiple well system with the application of boundary elementmethod (BEM) are discussed. The mathematical model of unsteady well flow is a boundary value problem ofparabolic differential equation. It is changed into an elliptic one by Laplace transform to eliminate time varia-ble. The image function of water head H can be solved by BEM. We derived the boundary integral equation ofthe transformed variable H and the discretization form of it, so that there is no need to discretize the bounda-ries of well walls and it becomes easier to solve the groundwater head H by numerical inversion. 展开更多
关键词 of Groundwater Unsteady Flow to a multiple Well System in a Confined Aquifer Laplace Transform Solution Boundary Element Analysis FLOW
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Infiltration by monocytes of the central nervous system and its role in multiple sclerosis: reflections on therapeutic strategies 被引量:1
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作者 Guangyong Zhang Qing Yao +9 位作者 Chubing Long Pengcheng Yi Jiali Song Luojia Wu Wei Wan Xiuqin Rao Yue Lin Gen Wei Jun Ying Fuzhou Hua 《Neural Regeneration Research》 SCIE CAS 2025年第3期779-793,共15页
Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple rol... Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood–brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases. 展开更多
关键词 blood–brain barrier MACROPHAGES MONOCYTES multiple sclerosis NEUROINFLAMMATION review therapy
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Estimation of detection threshold in multiple ship target situations with HF ground wave radar
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作者 Li Hongbo Shen Yiying Liu Yongtan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期739-744,共6页
A credible method of calculating the detection threshold is presented for the multiple target situations, which appear frequently in the lower Doppler velocity region during the surveillance of sea with HF ground wave... A credible method of calculating the detection threshold is presented for the multiple target situations, which appear frequently in the lower Doppler velocity region during the surveillance of sea with HF ground wave radar. This method defines a whole-peak-outlier elimination (WPOE) criterion, which is based on in-peak-samples correlation of each target echo spectra, to trim off the target signals and abnormal disturbances with great amplitude from the complex spectra. Therefore, cleaned background noise samples are obtained to improve the accuracy and reliability of noise level estimation. When the background noise is nonhomogeneous, the detection samples are limited and often occupied heavily with outliers. In this case, the problem that the detection threshold is overvalued can be solved. In applications on experimental data, it is verified that this method can reduce the miss alarm rate of signal detection effectively in multiple target situations as well as make the adaptability of the detector better. 展开更多
关键词 HF ground wave radar multiple target detection outlier elimination threshold estimation
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Defected Ground Structure Multiple Input-Output Antenna For Wireless Applications
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作者 Ramya Sridhar Vijayalakshimi Patteeswaran 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期2109-2122,共14页
In this paper,the investigation of a novel compact 2×2,2×1,and 1×1 Ultra-Wide Band(UWB)based Multiple-Input Multiple-Output(MIMO)antenna with Defected Ground Structure(DGS)is employed.The proposed Elect... In this paper,the investigation of a novel compact 2×2,2×1,and 1×1 Ultra-Wide Band(UWB)based Multiple-Input Multiple-Output(MIMO)antenna with Defected Ground Structure(DGS)is employed.The proposed Electromagnetic Radiation Structures(ERS)is composed of multiple radiating elements.These MIMO antennas are designed and analyzed with and without DGS.The feeding is introduced by a microstrip-fed line to significantly moderate the radiating structure’s overall size,which is 60×40×1 mm.The high directivity and divergence characteristics are attained by introducing the microstripfed lines perpendicular to each other.And the projected MIMO antenna structures are compared with others by using parameters like Return Loss(RL),Voltage Standing Wave Ratio(VSWR),Radiation Pattern(RP),radiation efficiency,and directivity.The same MIMO set-up is redesigned with DGS,and the resultant parameters are compared.Finally,the Multiple Input and Multiple Output Radiating Structures with and without DGS are compared for result considerations like RL,VSWR,RP,radiation efficiency,and directivity.This projected antenna displays an omnidirectional RP with moderate gain,which is highly recommended for human healthcare applications.By introducing the defected ground structure in bottom layer the lower cut-off frequencies of 2.3,4.5 and 6.0 GHz are achieved with few biological effects on radio propagation in human body communications.The proposed design covers numerous well-known wireless standards,along with dual-function DGS slots,and it can be easily integrated into Wireless Body Area Networks(WBAN)in medical applications.This WBAN links the autonomous nodes that may be situated either in the clothes,on-body or beneath the skin of a person.This system typically advances the complete human body and the inter-connected nodes through a wireless communication channel. 展开更多
关键词 MIMO-multiple input multiple output defected ground structure WBAN-wireless body area networks ULTRA-WIDEBAND voltage standing wave ratio
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